| File: | builds/wireshark/wireshark/epan/reassemble.c |
| Warning: | line 1905, column 12 Potential leak of memory pointed to by 'data' |
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| 1 | /* reassemble.c | |||
| 2 | * Routines for {fragment,segment} reassembly | |||
| 3 | * | |||
| 4 | * Wireshark - Network traffic analyzer | |||
| 5 | * By Gerald Combs <[email protected]> | |||
| 6 | * Copyright 1998 Gerald Combs | |||
| 7 | * | |||
| 8 | * SPDX-License-Identifier: GPL-2.0-or-later | |||
| 9 | */ | |||
| 10 | ||||
| 11 | #include "config.h" | |||
| 12 | ||||
| 13 | #include <string.h> | |||
| 14 | ||||
| 15 | #include <epan/packet.h> | |||
| 16 | #include <epan/exceptions.h> | |||
| 17 | #include <epan/reassemble.h> | |||
| 18 | #include <epan/tvbuff-int.h> | |||
| 19 | ||||
| 20 | #include <wsutil/str_util.h> | |||
| 21 | #include <wsutil/ws_assert.h> | |||
| 22 | ||||
| 23 | /* | |||
| 24 | * Functions for reassembly tables where the endpoint addresses, and a | |||
| 25 | * fragment ID, are used as the key. | |||
| 26 | */ | |||
| 27 | typedef struct _fragment_addresses_key { | |||
| 28 | address src; | |||
| 29 | address dst; | |||
| 30 | uint32_t id; | |||
| 31 | } fragment_addresses_key; | |||
| 32 | ||||
| 33 | GList* reassembly_table_list; | |||
| 34 | ||||
| 35 | static unsigned | |||
| 36 | fragment_addresses_hash(const void *k) | |||
| 37 | { | |||
| 38 | const fragment_addresses_key* key = (const fragment_addresses_key*) k; | |||
| 39 | unsigned hash_val; | |||
| 40 | /* | |||
| 41 | int i; | |||
| 42 | */ | |||
| 43 | ||||
| 44 | hash_val = 0; | |||
| 45 | ||||
| 46 | /* More than likely: in most captures src and dst addresses are the | |||
| 47 | same, and would hash the same. | |||
| 48 | We only use id as the hash as an optimization. | |||
| 49 | ||||
| 50 | for (i = 0; i < key->src.len; i++) | |||
| 51 | hash_val += key->src.data[i]; | |||
| 52 | for (i = 0; i < key->dst.len; i++) | |||
| 53 | hash_val += key->dst.data[i]; | |||
| 54 | */ | |||
| 55 | ||||
| 56 | hash_val += key->id; | |||
| 57 | ||||
| 58 | return hash_val; | |||
| 59 | } | |||
| 60 | ||||
| 61 | static int | |||
| 62 | fragment_addresses_equal(const void *k1, const void *k2) | |||
| 63 | { | |||
| 64 | const fragment_addresses_key* key1 = (const fragment_addresses_key*) k1; | |||
| 65 | const fragment_addresses_key* key2 = (const fragment_addresses_key*) k2; | |||
| 66 | ||||
| 67 | /* | |||
| 68 | * key.id is the first item to compare since it's the item most | |||
| 69 | * likely to differ between sessions, thus short-circuiting | |||
| 70 | * the comparison of addresses. | |||
| 71 | */ | |||
| 72 | return (key1->id == key2->id) && | |||
| 73 | (addresses_equal(&key1->src, &key2->src)) && | |||
| 74 | (addresses_equal(&key1->dst, &key2->dst)); | |||
| 75 | } | |||
| 76 | ||||
| 77 | /* | |||
| 78 | * Create a fragment key for temporary use; it can point to non- | |||
| 79 | * persistent data, and so must only be used to look up and | |||
| 80 | * delete entries, not to add them. | |||
| 81 | */ | |||
| 82 | static void * | |||
| 83 | fragment_addresses_temporary_key(const packet_info *pinfo, const uint32_t id, | |||
| 84 | const void *data _U___attribute__((unused))) | |||
| 85 | { | |||
| 86 | fragment_addresses_key *key = g_slice_new(fragment_addresses_key)((fragment_addresses_key*) g_slice_alloc (sizeof (fragment_addresses_key ))); | |||
| 87 | ||||
| 88 | /* | |||
| 89 | * Do a shallow copy of the addresses. | |||
| 90 | */ | |||
| 91 | copy_address_shallow(&key->src, &pinfo->src); | |||
| 92 | copy_address_shallow(&key->dst, &pinfo->dst); | |||
| 93 | key->id = id; | |||
| 94 | ||||
| 95 | return (void *)key; | |||
| 96 | } | |||
| 97 | ||||
| 98 | /* | |||
| 99 | * Create a fragment key for permanent use; it must point to persistent | |||
| 100 | * data, so that it can be used to add entries. | |||
| 101 | */ | |||
| 102 | static void * | |||
| 103 | fragment_addresses_persistent_key(const packet_info *pinfo, const uint32_t id, | |||
| 104 | const void *data _U___attribute__((unused))) | |||
| 105 | { | |||
| 106 | fragment_addresses_key *key = g_slice_new(fragment_addresses_key)((fragment_addresses_key*) g_slice_alloc (sizeof (fragment_addresses_key ))); | |||
| 107 | ||||
| 108 | /* | |||
| 109 | * Do a deep copy of the addresses. | |||
| 110 | */ | |||
| 111 | copy_address(&key->src, &pinfo->src); | |||
| 112 | copy_address(&key->dst, &pinfo->dst); | |||
| 113 | key->id = id; | |||
| 114 | ||||
| 115 | return (void *)key; | |||
| 116 | } | |||
| 117 | ||||
| 118 | static void | |||
| 119 | fragment_addresses_free_temporary_key(void *ptr) | |||
| 120 | { | |||
| 121 | fragment_addresses_key *key = (fragment_addresses_key *)ptr; | |||
| 122 | g_slice_free(fragment_addresses_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_key), ( key)); else (void) ((fragment_addresses_key*) 0 == (key)); } while (0); | |||
| 123 | } | |||
| 124 | ||||
| 125 | static void | |||
| 126 | fragment_addresses_free_persistent_key(void *ptr) | |||
| 127 | { | |||
| 128 | fragment_addresses_key *key = (fragment_addresses_key *)ptr; | |||
| 129 | ||||
| 130 | if(key){ | |||
| 131 | /* | |||
| 132 | * Free up the copies of the addresses from the old key. | |||
| 133 | */ | |||
| 134 | free_address(&key->src); | |||
| 135 | free_address(&key->dst); | |||
| 136 | ||||
| 137 | g_slice_free(fragment_addresses_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_key), ( key)); else (void) ((fragment_addresses_key*) 0 == (key)); } while (0); | |||
| 138 | } | |||
| 139 | } | |||
| 140 | ||||
| 141 | const reassembly_table_functions | |||
| 142 | addresses_reassembly_table_functions = { | |||
| 143 | fragment_addresses_hash, | |||
| 144 | fragment_addresses_equal, | |||
| 145 | fragment_addresses_temporary_key, | |||
| 146 | fragment_addresses_persistent_key, | |||
| 147 | fragment_addresses_free_temporary_key, | |||
| 148 | fragment_addresses_free_persistent_key | |||
| 149 | }; | |||
| 150 | ||||
| 151 | /* | |||
| 152 | * Functions for reassembly tables where the endpoint addresses and ports, | |||
| 153 | * and a fragment ID, are used as the key. | |||
| 154 | */ | |||
| 155 | typedef struct _fragment_addresses_ports_key { | |||
| 156 | address src_addr; | |||
| 157 | address dst_addr; | |||
| 158 | uint32_t src_port; | |||
| 159 | uint32_t dst_port; | |||
| 160 | uint32_t id; | |||
| 161 | } fragment_addresses_ports_key; | |||
| 162 | ||||
| 163 | static unsigned | |||
| 164 | fragment_addresses_ports_hash(const void *k) | |||
| 165 | { | |||
| 166 | const fragment_addresses_ports_key* key = (const fragment_addresses_ports_key*) k; | |||
| 167 | unsigned hash_val; | |||
| 168 | /* | |||
| 169 | int i; | |||
| 170 | */ | |||
| 171 | ||||
| 172 | hash_val = 0; | |||
| 173 | ||||
| 174 | /* More than likely: in most captures src and dst addresses and ports | |||
| 175 | are the same, and would hash the same. | |||
| 176 | We only use id as the hash as an optimization. | |||
| 177 | ||||
| 178 | for (i = 0; i < key->src.len; i++) | |||
| 179 | hash_val += key->src_addr.data[i]; | |||
| 180 | for (i = 0; i < key->dst.len; i++) | |||
| 181 | hash_val += key->dst_addr.data[i]; | |||
| 182 | hash_val += key->src_port; | |||
| 183 | hash_val += key->dst_port; | |||
| 184 | */ | |||
| 185 | ||||
| 186 | hash_val += key->id; | |||
| 187 | ||||
| 188 | return hash_val; | |||
| 189 | } | |||
| 190 | ||||
| 191 | static int | |||
| 192 | fragment_addresses_ports_equal(const void *k1, const void *k2) | |||
| 193 | { | |||
| 194 | const fragment_addresses_ports_key* key1 = (const fragment_addresses_ports_key*) k1; | |||
| 195 | const fragment_addresses_ports_key* key2 = (const fragment_addresses_ports_key*) k2; | |||
| 196 | ||||
| 197 | /* | |||
| 198 | * key.id is the first item to compare since it's the item most | |||
| 199 | * likely to differ between sessions, thus short-circuiting | |||
| 200 | * the comparison of addresses and ports. | |||
| 201 | */ | |||
| 202 | return (key1->id == key2->id) && | |||
| 203 | (addresses_equal(&key1->src_addr, &key2->src_addr)) && | |||
| 204 | (addresses_equal(&key1->dst_addr, &key2->dst_addr)) && | |||
| 205 | (key1->src_port == key2->src_port) && | |||
| 206 | (key1->dst_port == key2->dst_port); | |||
| 207 | } | |||
| 208 | ||||
| 209 | /* | |||
| 210 | * Create a fragment key for temporary use; it can point to non- | |||
| 211 | * persistent data, and so must only be used to look up and | |||
| 212 | * delete entries, not to add them. | |||
| 213 | */ | |||
| 214 | static void * | |||
| 215 | fragment_addresses_ports_temporary_key(const packet_info *pinfo, const uint32_t id, | |||
| 216 | const void *data _U___attribute__((unused))) | |||
| 217 | { | |||
| 218 | fragment_addresses_ports_key *key = g_slice_new(fragment_addresses_ports_key)((fragment_addresses_ports_key*) g_slice_alloc (sizeof (fragment_addresses_ports_key ))); | |||
| 219 | ||||
| 220 | /* | |||
| 221 | * Do a shallow copy of the addresses. | |||
| 222 | */ | |||
| 223 | copy_address_shallow(&key->src_addr, &pinfo->src); | |||
| 224 | copy_address_shallow(&key->dst_addr, &pinfo->dst); | |||
| 225 | key->src_port = pinfo->srcport; | |||
| 226 | key->dst_port = pinfo->destport; | |||
| 227 | key->id = id; | |||
| 228 | ||||
| 229 | return (void *)key; | |||
| 230 | } | |||
| 231 | ||||
| 232 | /* | |||
| 233 | * Create a fragment key for permanent use; it must point to persistent | |||
| 234 | * data, so that it can be used to add entries. | |||
| 235 | */ | |||
| 236 | static void * | |||
| 237 | fragment_addresses_ports_persistent_key(const packet_info *pinfo, | |||
| 238 | const uint32_t id, const void *data _U___attribute__((unused))) | |||
| 239 | { | |||
| 240 | fragment_addresses_ports_key *key = g_slice_new(fragment_addresses_ports_key)((fragment_addresses_ports_key*) g_slice_alloc (sizeof (fragment_addresses_ports_key ))); | |||
| 241 | ||||
| 242 | /* | |||
| 243 | * Do a deep copy of the addresses. | |||
| 244 | */ | |||
| 245 | copy_address(&key->src_addr, &pinfo->src); | |||
| 246 | copy_address(&key->dst_addr, &pinfo->dst); | |||
| 247 | key->src_port = pinfo->srcport; | |||
| 248 | key->dst_port = pinfo->destport; | |||
| 249 | key->id = id; | |||
| 250 | ||||
| 251 | return (void *)key; | |||
| 252 | } | |||
| 253 | ||||
| 254 | static void | |||
| 255 | fragment_addresses_ports_free_temporary_key(void *ptr) | |||
| 256 | { | |||
| 257 | fragment_addresses_ports_key *key = (fragment_addresses_ports_key *)ptr; | |||
| 258 | g_slice_free(fragment_addresses_ports_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_ports_key ), (key)); else (void) ((fragment_addresses_ports_key*) 0 == ( key)); } while (0); | |||
| 259 | } | |||
| 260 | ||||
| 261 | static void | |||
| 262 | fragment_addresses_ports_free_persistent_key(void *ptr) | |||
| 263 | { | |||
| 264 | fragment_addresses_ports_key *key = (fragment_addresses_ports_key *)ptr; | |||
| 265 | ||||
| 266 | if(key){ | |||
| 267 | /* | |||
| 268 | * Free up the copies of the addresses from the old key. | |||
| 269 | */ | |||
| 270 | free_address(&key->src_addr); | |||
| 271 | free_address(&key->dst_addr); | |||
| 272 | ||||
| 273 | g_slice_free(fragment_addresses_ports_key, key)do { if (1) g_slice_free1 (sizeof (fragment_addresses_ports_key ), (key)); else (void) ((fragment_addresses_ports_key*) 0 == ( key)); } while (0); | |||
| 274 | } | |||
| 275 | } | |||
| 276 | ||||
| 277 | const reassembly_table_functions | |||
| 278 | addresses_ports_reassembly_table_functions = { | |||
| 279 | fragment_addresses_ports_hash, | |||
| 280 | fragment_addresses_ports_equal, | |||
| 281 | fragment_addresses_ports_temporary_key, | |||
| 282 | fragment_addresses_ports_persistent_key, | |||
| 283 | fragment_addresses_ports_free_temporary_key, | |||
| 284 | fragment_addresses_ports_free_persistent_key | |||
| 285 | }; | |||
| 286 | ||||
| 287 | typedef struct _reassembled_key { | |||
| 288 | uint32_t id; | |||
| 289 | uint32_t frame; | |||
| 290 | } reassembled_key; | |||
| 291 | ||||
| 292 | static int | |||
| 293 | reassembled_equal(const void *k1, const void *k2) | |||
| 294 | { | |||
| 295 | const reassembled_key* key1 = (const reassembled_key*) k1; | |||
| 296 | const reassembled_key* key2 = (const reassembled_key*) k2; | |||
| 297 | ||||
| 298 | /* | |||
| 299 | * We assume that the frame numbers are unlikely to be equal, | |||
| 300 | * so we check them first. | |||
| 301 | */ | |||
| 302 | return key1->frame == key2->frame && key1->id == key2->id; | |||
| 303 | } | |||
| 304 | ||||
| 305 | static unsigned | |||
| 306 | reassembled_hash(const void *k) | |||
| 307 | { | |||
| 308 | const reassembled_key* key = (const reassembled_key*) k; | |||
| 309 | ||||
| 310 | return key->frame; | |||
| 311 | } | |||
| 312 | ||||
| 313 | static void | |||
| 314 | reassembled_key_free(void *ptr) | |||
| 315 | { | |||
| 316 | g_slice_free(reassembled_key, (reassembled_key *)ptr)do { if (1) g_slice_free1 (sizeof (reassembled_key), ((reassembled_key *)ptr)); else (void) ((reassembled_key*) 0 == ((reassembled_key *)ptr)); } while (0); | |||
| 317 | } | |||
| 318 | ||||
| 319 | /* --------------fragment_item functions ----------- */ | |||
| 320 | static fragment_item* | |||
| 321 | new_fragment_item(uint32_t frame, uint32_t offset, uint32_t len) | |||
| 322 | { | |||
| 323 | fragment_item *fd; | |||
| 324 | ||||
| 325 | fd = g_slice_new(fragment_item)((fragment_item*) g_slice_alloc (sizeof (fragment_item))); | |||
| 326 | fd->next = NULL((void*)0); | |||
| 327 | fd->flags = 0; | |||
| 328 | fd->frame = frame; | |||
| 329 | fd->offset = offset; | |||
| 330 | fd->len = len; | |||
| 331 | fd->tvb_data = NULL((void*)0); | |||
| 332 | ||||
| 333 | return fd; | |||
| 334 | } | |||
| 335 | ||||
| 336 | static void | |||
| 337 | fragment_item_free_tvb(fragment_item *fd_i) | |||
| 338 | { | |||
| 339 | /* If this is a subset of the tvb created for the head after | |||
| 340 | * dissembly, don't free it (that would cause memory errors; | |||
| 341 | * the parent will be freed later.) */ | |||
| 342 | if (fd_i->flags & FD_SUBSET_TVB0x0020) | |||
| 343 | fd_i->flags &= ~FD_SUBSET_TVB0x0020; | |||
| 344 | else if (fd_i->tvb_data) | |||
| 345 | tvb_free(fd_i->tvb_data); | |||
| 346 | ||||
| 347 | fd_i->tvb_data=NULL((void*)0); | |||
| 348 | } | |||
| 349 | ||||
| 350 | /* Returns the pointer to the next item so that the list can be freed. */ | |||
| 351 | static fragment_item* | |||
| 352 | fragment_item_free(fragment_item *fd_i) | |||
| 353 | { | |||
| 354 | fragment_item *fd_next = fd_i->next; | |||
| 355 | fragment_item_free_tvb(fd_i); | |||
| 356 | g_slice_free(fragment_item, fd_i)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd_i)); else (void) ((fragment_item*) 0 == (fd_i)); } while (0); | |||
| 357 | return fd_next; | |||
| 358 | } | |||
| 359 | ||||
| 360 | /* ------------------------- */ | |||
| 361 | static fragment_head *new_head(const uint32_t flags) | |||
| 362 | { | |||
| 363 | fragment_head *fd_head; | |||
| 364 | /* If head/first structure in list only holds no other data than | |||
| 365 | * 'datalen' then we don't have to change the head of the list | |||
| 366 | * even if we want to keep it sorted | |||
| 367 | */ | |||
| 368 | fd_head=g_slice_new0(fragment_head)((fragment_head*) g_slice_alloc0 (sizeof (fragment_head))); | |||
| 369 | ||||
| 370 | fd_head->flags=flags; | |||
| 371 | return fd_head; | |||
| 372 | } | |||
| 373 | ||||
| 374 | /* | |||
| 375 | * For a reassembled-packet hash table entry, free the fragment data | |||
| 376 | * to which the value refers. (The key is freed by reassembled_key_free.) | |||
| 377 | */ | |||
| 378 | static void | |||
| 379 | free_fd_head(fragment_head *fd_head) | |||
| 380 | { | |||
| 381 | fragment_item *fd_i; | |||
| 382 | ||||
| 383 | if (fd_head->flags & FD_SUBSET_TVB0x0020) | |||
| 384 | fd_head->tvb_data = NULL((void*)0); | |||
| 385 | if (fd_head->tvb_data) | |||
| 386 | tvb_free(fd_head->tvb_data); | |||
| 387 | fd_i = fd_head->next; | |||
| 388 | while (fd_i != NULL((void*)0)) { | |||
| 389 | fd_i = fragment_item_free(fd_i); | |||
| 390 | } | |||
| 391 | g_slice_free(fragment_head, fd_head)do { if (1) g_slice_free1 (sizeof (fragment_head), (fd_head)) ; else (void) ((fragment_head*) 0 == (fd_head)); } while (0); | |||
| 392 | } | |||
| 393 | ||||
| 394 | static void | |||
| 395 | unref_fd_head(void *data) | |||
| 396 | { | |||
| 397 | fragment_head *fd_head = (fragment_head *) data; | |||
| 398 | fd_head->ref_count--; | |||
| 399 | ||||
| 400 | if (fd_head->ref_count == 0) { | |||
| 401 | free_fd_head(fd_head); | |||
| 402 | } | |||
| 403 | } | |||
| 404 | ||||
| 405 | /* | |||
| 406 | * For a fragment hash table entry, free the associated fragments. | |||
| 407 | * The entry value (fd_chain) is freed herein and the entry is freed | |||
| 408 | * when the key freeing routine is called (as a consequence of returning | |||
| 409 | * true from this function). | |||
| 410 | */ | |||
| 411 | static gboolean | |||
| 412 | free_all_fragments(void *key_arg _U___attribute__((unused)), void *value, void *user_data _U___attribute__((unused))) | |||
| 413 | { | |||
| 414 | fragment_head *fd_head; | |||
| 415 | ||||
| 416 | /* g_hash_table_new_full() was used to supply a function | |||
| 417 | * to free the key and anything to which it points | |||
| 418 | */ | |||
| 419 | fd_head = (fragment_head *)value; | |||
| 420 | free_fd_head(fd_head); | |||
| 421 | ||||
| 422 | return TRUE(!(0)); | |||
| 423 | } | |||
| 424 | ||||
| 425 | static void | |||
| 426 | reassembled_table_insert(GHashTable *reassembled_table, reassembled_key *key, fragment_head *fd_head) | |||
| 427 | { | |||
| 428 | fragment_head *old_fd_head; | |||
| 429 | fd_head->ref_count++; | |||
| 430 | if ((old_fd_head = g_hash_table_lookup(reassembled_table, key)) != NULL((void*)0)) { | |||
| 431 | if (old_fd_head->ref_count == 1) { | |||
| 432 | /* We're replacing the last entry in the reassembled | |||
| 433 | * table for an old reassembly. Does it have a tvb? | |||
| 434 | * We might still be using that tvb's memory for an | |||
| 435 | * address via set_address_tvb(). (See #19094.) | |||
| 436 | */ | |||
| 437 | if (old_fd_head->tvb_data && fd_head->tvb_data) { | |||
| 438 | /* Free it when the new tvb is freed */ | |||
| 439 | tvb_set_child_real_data_tvbuff(fd_head->tvb_data, old_fd_head->tvb_data); | |||
| 440 | } | |||
| 441 | /* XXX: Set the old data to NULL regardless. If we | |||
| 442 | * have old data but not new data, that is odd (we're | |||
| 443 | * replacing a reassembly with tvb data with something | |||
| 444 | * with no tvb data, possibly because a zero length or | |||
| 445 | * null tvb was passed into a defragment function, | |||
| 446 | * which is a dissector bug.) | |||
| 447 | * This leaks the tvb data if we couldn't add it to | |||
| 448 | * a new tvb's chain, but we might not be able to free | |||
| 449 | * it yet if set_address_tvb() was used. | |||
| 450 | */ | |||
| 451 | old_fd_head->tvb_data = NULL((void*)0); | |||
| 452 | } | |||
| 453 | } | |||
| 454 | g_hash_table_insert(reassembled_table, key, fd_head); | |||
| 455 | } | |||
| 456 | ||||
| 457 | typedef struct register_reassembly_table { | |||
| 458 | reassembly_table *table; | |||
| 459 | const reassembly_table_functions *funcs; | |||
| 460 | } register_reassembly_table_t; | |||
| 461 | ||||
| 462 | /* | |||
| 463 | * Register a reassembly table. | |||
| 464 | */ | |||
| 465 | void | |||
| 466 | reassembly_table_register(reassembly_table *table, | |||
| 467 | const reassembly_table_functions *funcs) | |||
| 468 | { | |||
| 469 | register_reassembly_table_t* reg_table; | |||
| 470 | ||||
| 471 | DISSECTOR_ASSERT(table)((void) ((table) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\"" , "epan/reassemble.c", 471, "table")))); | |||
| 472 | DISSECTOR_ASSERT(funcs)((void) ((funcs) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\"" , "epan/reassemble.c", 472, "funcs")))); | |||
| 473 | ||||
| 474 | reg_table = g_new(register_reassembly_table_t,1)((register_reassembly_table_t *) g_malloc_n ((1), sizeof (register_reassembly_table_t ))); | |||
| 475 | ||||
| 476 | reg_table->table = table; | |||
| 477 | reg_table->funcs = funcs; | |||
| 478 | ||||
| 479 | reassembly_table_list = g_list_prepend(reassembly_table_list, reg_table); | |||
| 480 | } | |||
| 481 | ||||
| 482 | /* | |||
| 483 | * Initialize a reassembly table, with specified functions. | |||
| 484 | */ | |||
| 485 | void | |||
| 486 | reassembly_table_init(reassembly_table *table, | |||
| 487 | const reassembly_table_functions *funcs) | |||
| 488 | { | |||
| 489 | if (table->temporary_key_func == NULL((void*)0)) | |||
| 490 | table->temporary_key_func = funcs->temporary_key_func; | |||
| 491 | if (table->persistent_key_func == NULL((void*)0)) | |||
| 492 | table->persistent_key_func = funcs->persistent_key_func; | |||
| 493 | if (table->free_temporary_key_func == NULL((void*)0)) | |||
| 494 | table->free_temporary_key_func = funcs->free_temporary_key_func; | |||
| 495 | if (table->fragment_table != NULL((void*)0)) { | |||
| 496 | /* | |||
| 497 | * The fragment hash table exists. | |||
| 498 | * | |||
| 499 | * Remove all entries and free fragment data for each entry. | |||
| 500 | * | |||
| 501 | * The keys, and anything to which they point, are freed by | |||
| 502 | * calling the table's key freeing function. The values | |||
| 503 | * are freed in free_all_fragments(). | |||
| 504 | */ | |||
| 505 | g_hash_table_foreach_remove(table->fragment_table, | |||
| 506 | free_all_fragments, NULL((void*)0)); | |||
| 507 | } else { | |||
| 508 | /* The fragment table does not exist. Create it */ | |||
| 509 | table->fragment_table = g_hash_table_new_full(funcs->hash_func, | |||
| 510 | funcs->equal_func, funcs->free_persistent_key_func, NULL((void*)0)); | |||
| 511 | } | |||
| 512 | ||||
| 513 | if (table->reassembled_table != NULL((void*)0)) { | |||
| 514 | /* | |||
| 515 | * The reassembled-packet hash table exists. | |||
| 516 | * | |||
| 517 | * Remove all entries and free reassembled packet | |||
| 518 | * data and key for each entry. | |||
| 519 | */ | |||
| 520 | g_hash_table_remove_all(table->reassembled_table); | |||
| 521 | } else { | |||
| 522 | /* The fragment table does not exist. Create it */ | |||
| 523 | table->reassembled_table = g_hash_table_new_full(reassembled_hash, | |||
| 524 | reassembled_equal, reassembled_key_free, unref_fd_head); | |||
| 525 | } | |||
| 526 | } | |||
| 527 | ||||
| 528 | /* | |||
| 529 | * Destroy a reassembly table. | |||
| 530 | */ | |||
| 531 | void | |||
| 532 | reassembly_table_destroy(reassembly_table *table) | |||
| 533 | { | |||
| 534 | /* | |||
| 535 | * Clear the function pointers. | |||
| 536 | */ | |||
| 537 | table->temporary_key_func = NULL((void*)0); | |||
| 538 | table->persistent_key_func = NULL((void*)0); | |||
| 539 | table->free_temporary_key_func = NULL((void*)0); | |||
| 540 | if (table->fragment_table != NULL((void*)0)) { | |||
| 541 | /* | |||
| 542 | * The fragment hash table exists. | |||
| 543 | * | |||
| 544 | * Remove all entries and free fragment data for each entry. | |||
| 545 | * | |||
| 546 | * The keys, and anything to which they point, are freed by | |||
| 547 | * calling the table's key freeing function. The values | |||
| 548 | * are freed in free_all_fragments(). | |||
| 549 | */ | |||
| 550 | g_hash_table_foreach_remove(table->fragment_table, | |||
| 551 | free_all_fragments, NULL((void*)0)); | |||
| 552 | ||||
| 553 | /* | |||
| 554 | * Now destroy the hash table. | |||
| 555 | */ | |||
| 556 | g_hash_table_destroy(table->fragment_table); | |||
| 557 | table->fragment_table = NULL((void*)0); | |||
| 558 | } | |||
| 559 | if (table->reassembled_table != NULL((void*)0)) { | |||
| 560 | /* | |||
| 561 | * The reassembled-packet hash table exists. | |||
| 562 | * | |||
| 563 | * Remove all entries and free reassembled packet | |||
| 564 | * data and key for each entry. | |||
| 565 | */ | |||
| 566 | ||||
| 567 | g_hash_table_remove_all(table->reassembled_table); | |||
| 568 | ||||
| 569 | /* | |||
| 570 | * Now destroy the hash table. | |||
| 571 | */ | |||
| 572 | g_hash_table_destroy(table->reassembled_table); | |||
| 573 | table->reassembled_table = NULL((void*)0); | |||
| 574 | } | |||
| 575 | } | |||
| 576 | ||||
| 577 | /* | |||
| 578 | * Look up an fd_head in the fragment table, optionally returning the key | |||
| 579 | * for it. | |||
| 580 | */ | |||
| 581 | static fragment_head * | |||
| 582 | lookup_fd_head(reassembly_table *table, const packet_info *pinfo, | |||
| 583 | const uint32_t id, const void *data, void * *orig_keyp) | |||
| 584 | { | |||
| 585 | void *key; | |||
| 586 | void *value; | |||
| 587 | ||||
| 588 | /* Create key to search hash with */ | |||
| 589 | key = table->temporary_key_func(pinfo, id, data); | |||
| 590 | ||||
| 591 | /* | |||
| 592 | * Look up the reassembly in the fragment table. | |||
| 593 | */ | |||
| 594 | if (!g_hash_table_lookup_extended(table->fragment_table, key, orig_keyp, | |||
| 595 | &value)) | |||
| 596 | value = NULL((void*)0); | |||
| 597 | /* Free the key */ | |||
| 598 | table->free_temporary_key_func(key); | |||
| 599 | ||||
| 600 | return (fragment_head *)value; | |||
| 601 | } | |||
| 602 | ||||
| 603 | /* | |||
| 604 | * Insert an fd_head into the fragment table, and return the key used. | |||
| 605 | */ | |||
| 606 | static void * | |||
| 607 | insert_fd_head(reassembly_table *table, fragment_head *fd_head, | |||
| 608 | const packet_info *pinfo, const uint32_t id, const void *data) | |||
| 609 | { | |||
| 610 | void *key; | |||
| 611 | ||||
| 612 | /* | |||
| 613 | * We're going to use the key to insert the fragment, | |||
| 614 | * so make a persistent version of it. | |||
| 615 | */ | |||
| 616 | key = table->persistent_key_func(pinfo, id, data); | |||
| 617 | g_hash_table_insert(table->fragment_table, key, fd_head); | |||
| 618 | return key; | |||
| 619 | } | |||
| 620 | ||||
| 621 | /* This function cleans up the stored state and removes the reassembly data and | |||
| 622 | * (with one exception) all allocated memory for matching reassembly. | |||
| 623 | * | |||
| 624 | * The exception is : | |||
| 625 | * If the PDU was already completely reassembled, then the tvbuff containing the | |||
| 626 | * reassembled data WILL NOT be free()d, and the pointer to that tvbuff will be | |||
| 627 | * returned. | |||
| 628 | * Othervise the function will return NULL. | |||
| 629 | * | |||
| 630 | * So, if you call fragment_delete and it returns non-NULL, YOU are responsible | |||
| 631 | * to tvb_free() that tvbuff. | |||
| 632 | */ | |||
| 633 | tvbuff_t * | |||
| 634 | fragment_delete(reassembly_table *table, const packet_info *pinfo, | |||
| 635 | const uint32_t id, const void *data) | |||
| 636 | { | |||
| 637 | fragment_head *fd_head; | |||
| 638 | fragment_item *fd; | |||
| 639 | tvbuff_t *fd_tvb_data=NULL((void*)0); | |||
| 640 | void *key; | |||
| 641 | ||||
| 642 | fd_head = lookup_fd_head(table, pinfo, id, data, &key); | |||
| 643 | if(fd_head==NULL((void*)0)){ | |||
| 644 | /* We do not recognize this as a PDU we have seen before. return */ | |||
| 645 | return NULL((void*)0); | |||
| 646 | } | |||
| 647 | ||||
| 648 | fd_tvb_data=fd_head->tvb_data; | |||
| 649 | /* loop over all partial fragments and free any tvbuffs */ | |||
| 650 | fd = fd_head->next; | |||
| 651 | while (fd != NULL((void*)0)) { | |||
| 652 | fd = fragment_item_free(fd); | |||
| 653 | } | |||
| 654 | g_slice_free(fragment_head, fd_head)do { if (1) g_slice_free1 (sizeof (fragment_head), (fd_head)) ; else (void) ((fragment_head*) 0 == (fd_head)); } while (0); | |||
| 655 | g_hash_table_remove(table->fragment_table, key); | |||
| 656 | ||||
| 657 | return fd_tvb_data; | |||
| 658 | } | |||
| 659 | ||||
| 660 | /* This function is used to check if there is partial or completed reassembly state | |||
| 661 | * matching this packet. I.e. Is there reassembly going on or not for this packet? | |||
| 662 | */ | |||
| 663 | fragment_head * | |||
| 664 | fragment_get(reassembly_table *table, const packet_info *pinfo, | |||
| 665 | const uint32_t id, const void *data) | |||
| 666 | { | |||
| 667 | return lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 668 | } | |||
| 669 | ||||
| 670 | fragment_head * | |||
| 671 | fragment_get_reassembled_id(reassembly_table *table, const packet_info *pinfo, | |||
| 672 | const uint32_t id) | |||
| 673 | { | |||
| 674 | fragment_head *fd_head; | |||
| 675 | reassembled_key key; | |||
| 676 | ||||
| 677 | /* create key to search hash with */ | |||
| 678 | key.frame = pinfo->num; | |||
| 679 | key.id = id; | |||
| 680 | fd_head = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &key); | |||
| 681 | ||||
| 682 | return fd_head; | |||
| 683 | } | |||
| 684 | ||||
| 685 | /* To specify the offset for the fragment numbering, the first fragment is added with 0, and | |||
| 686 | * afterwards this offset is set. All additional calls to off_seq_check will calculate | |||
| 687 | * the number in sequence in regards to the offset */ | |||
| 688 | void | |||
| 689 | fragment_add_seq_offset(reassembly_table *table, const packet_info *pinfo, const uint32_t id, | |||
| 690 | const void *data, const uint32_t fragment_offset) | |||
| 691 | { | |||
| 692 | fragment_head *fd_head; | |||
| 693 | ||||
| 694 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 695 | if (!fd_head) | |||
| 696 | return; | |||
| 697 | ||||
| 698 | /* Resetting the offset is not allowed */ | |||
| 699 | if ( fd_head->fragment_nr_offset != 0 ) | |||
| 700 | return; | |||
| 701 | ||||
| 702 | fd_head->fragment_nr_offset = fragment_offset; | |||
| 703 | } | |||
| 704 | ||||
| 705 | static void | |||
| 706 | update_first_gap(fragment_head *fd_head, fragment_item *inserted, bool_Bool multi_insert) | |||
| 707 | { | |||
| 708 | uint32_t frag_end = inserted->offset + inserted->len; | |||
| 709 | fragment_item *iter; | |||
| 710 | uint32_t contiguous; | |||
| 711 | ||||
| 712 | if (inserted->offset > fd_head->contiguous_len) { | |||
| 713 | /* first inserted node is after first gap */ | |||
| 714 | return; | |||
| 715 | } else if (fd_head->first_gap == NULL((void*)0)) { | |||
| 716 | /* we haven't seen first fragment yet */ | |||
| 717 | if (inserted->offset != 0) { | |||
| 718 | /* inserted node is not first fragment */ | |||
| 719 | return; | |||
| 720 | } | |||
| 721 | contiguous = inserted->len; | |||
| 722 | iter = inserted; | |||
| 723 | } else { | |||
| 724 | contiguous = MAX(fd_head->contiguous_len, frag_end)(((fd_head->contiguous_len) > (frag_end)) ? (fd_head-> contiguous_len) : (frag_end)); | |||
| 725 | iter = multi_insert ? inserted : fd_head->first_gap; | |||
| 726 | } | |||
| 727 | ||||
| 728 | while (iter->next) { | |||
| 729 | if (iter->next->offset > contiguous) { | |||
| 730 | break; | |||
| 731 | } | |||
| 732 | iter = iter->next; | |||
| 733 | contiguous = MAX(contiguous, iter->offset + iter->len)(((contiguous) > (iter->offset + iter->len)) ? (contiguous ) : (iter->offset + iter->len)); | |||
| 734 | } | |||
| 735 | ||||
| 736 | /* iter is either pointing to last fragment before gap or tail */ | |||
| 737 | fd_head->first_gap = iter; | |||
| 738 | fd_head->contiguous_len = contiguous; | |||
| 739 | } | |||
| 740 | ||||
| 741 | /* | |||
| 742 | * Keeping first gap and contiguous length in sync significantly speeds up | |||
| 743 | * LINK_FRAG() when fragments in capture file are mostly ordered. However, when | |||
| 744 | * fragments are removed from the list, the first gap can point to fragments | |||
| 745 | * that were either moved to another list or freed. Therefore when any fragment | |||
| 746 | * before first gap is removed, the first gap (and contiguous length) must be | |||
| 747 | * invalidated. | |||
| 748 | */ | |||
| 749 | static void fragment_reset_first_gap(fragment_head *fd_head) | |||
| 750 | { | |||
| 751 | fd_head->first_gap = NULL((void*)0); | |||
| 752 | fd_head->contiguous_len = 0; | |||
| 753 | if (fd_head->next) { | |||
| 754 | bool_Bool multi_insert = (fd_head->next->next != NULL((void*)0)); | |||
| 755 | update_first_gap(fd_head, fd_head->next, multi_insert); | |||
| 756 | } | |||
| 757 | } | |||
| 758 | ||||
| 759 | /* | |||
| 760 | * Determines whether list modification requires first gap reset. On entry | |||
| 761 | * modified is NULL if all elements were removed, otherwise it points to | |||
| 762 | * element (reachable from fd_head) whose next pointer was changed. | |||
| 763 | */ | |||
| 764 | static void fragment_items_removed(fragment_head *fd_head, fragment_item *modified) | |||
| 765 | { | |||
| 766 | if ((fd_head->first_gap == modified) || | |||
| 767 | ((modified != NULL((void*)0)) && (modified->offset > fd_head->contiguous_len))) { | |||
| 768 | /* Removed elements were after first gap */ | |||
| 769 | return; | |||
| 770 | } | |||
| 771 | fragment_reset_first_gap(fd_head); | |||
| 772 | } | |||
| 773 | ||||
| 774 | /* | |||
| 775 | * For use with fragment_add (and not the fragment_add_seq functions). | |||
| 776 | * When the reassembled result is wrong (perhaps it needs to be extended), this | |||
| 777 | * function clears any previous reassembly result, allowing the new reassembled | |||
| 778 | * length to be set again. | |||
| 779 | */ | |||
| 780 | static void | |||
| 781 | fragment_reset_defragmentation(fragment_head *fd_head) | |||
| 782 | { | |||
| 783 | /* Caller must ensure that this function is only called when | |||
| 784 | * defragmentation is safe to undo. */ | |||
| 785 | DISSECTOR_ASSERT(fd_head->flags & FD_DEFRAGMENTED)((void) ((fd_head->flags & 0x0001) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 785, "fd_head->flags & 0x0001" )))); | |||
| 786 | ||||
| 787 | for (fragment_item *fd_i = fd_head->next; fd_i; fd_i = fd_i->next) { | |||
| 788 | if (!fd_i->tvb_data) { | |||
| 789 | fd_i->tvb_data = tvb_new_subset_remaining(fd_head->tvb_data, fd_i->offset); | |||
| 790 | fd_i->flags |= FD_SUBSET_TVB0x0020; | |||
| 791 | } | |||
| 792 | fd_i->flags &= (~FD_TOOLONGFRAGMENT0x0010) & (~FD_MULTIPLETAILS0x0008); | |||
| 793 | } | |||
| 794 | fd_head->flags &= ~(FD_DEFRAGMENTED0x0001|FD_PARTIAL_REASSEMBLY0x0040|FD_DATALEN_SET0x0400); | |||
| 795 | fd_head->flags &= ~(FD_TOOLONGFRAGMENT0x0010|FD_MULTIPLETAILS0x0008); | |||
| 796 | fd_head->datalen = 0; | |||
| 797 | fd_head->reassembled_in = 0; | |||
| 798 | fd_head->reas_in_layer_num = 0; | |||
| 799 | } | |||
| 800 | ||||
| 801 | /* This function can be used to explicitly set the total length (if known) | |||
| 802 | * for reassembly of a PDU. | |||
| 803 | * This is useful for reassembly of PDUs where one may have the total length specified | |||
| 804 | * in the first fragment instead of as for, say, IPv4 where a flag indicates which | |||
| 805 | * is the last fragment. | |||
| 806 | * | |||
| 807 | * Such protocols might fragment_add with a more_frags==true for every fragment | |||
| 808 | * and just tell the reassembly engine the expected total length of the reassembled data | |||
| 809 | * using fragment_set_tot_len immediately after doing fragment_add for the first packet. | |||
| 810 | * | |||
| 811 | * Note that for FD_BLOCKSEQUENCE tot_len is the index for the tail fragment. | |||
| 812 | * i.e. since the block numbers start at 0, if we specify tot_len==2, that | |||
| 813 | * actually means we want to defragment 3 blocks, block 0, 1 and 2. | |||
| 814 | */ | |||
| 815 | void | |||
| 816 | fragment_set_tot_len(reassembly_table *table, const packet_info *pinfo, | |||
| 817 | const uint32_t id, const void *data, const uint32_t tot_len) | |||
| 818 | { | |||
| 819 | fragment_head *fd_head; | |||
| 820 | fragment_item *fd; | |||
| 821 | uint32_t max_offset = 0; | |||
| 822 | ||||
| 823 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 824 | if (!fd_head) | |||
| 825 | return; | |||
| 826 | ||||
| 827 | /* If we're setting a block sequence number, verify that it | |||
| 828 | * doesn't conflict with values set by existing fragments. | |||
| 829 | * XXX - eliminate this check? | |||
| 830 | */ | |||
| 831 | if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) { | |||
| 832 | for (fd = fd_head->next; fd; fd = fd->next) { | |||
| 833 | if (fd->offset > max_offset) { | |||
| 834 | max_offset = fd->offset; | |||
| 835 | if (max_offset > tot_len) { | |||
| 836 | fd_head->error = "Bad total reassembly block count"; | |||
| 837 | THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error)); | |||
| 838 | } | |||
| 839 | } | |||
| 840 | } | |||
| 841 | } | |||
| 842 | ||||
| 843 | if (fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 844 | if (max_offset != tot_len) { | |||
| 845 | fd_head->error = "Defragmented complete but total length not satisfied"; | |||
| 846 | THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error)); | |||
| 847 | } | |||
| 848 | } | |||
| 849 | ||||
| 850 | /* We got this far so the value is sane. */ | |||
| 851 | fd_head->datalen = tot_len; | |||
| 852 | fd_head->flags |= FD_DATALEN_SET0x0400; | |||
| 853 | } | |||
| 854 | ||||
| 855 | void | |||
| 856 | fragment_reset_tot_len(reassembly_table *table, const packet_info *pinfo, | |||
| 857 | const uint32_t id, const void *data, const uint32_t tot_len) | |||
| 858 | { | |||
| 859 | fragment_head *fd_head; | |||
| 860 | ||||
| 861 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 862 | if (!fd_head) | |||
| 863 | return; | |||
| 864 | ||||
| 865 | /* | |||
| 866 | * If FD_PARTIAL_REASSEMBLY is set, it would make the next fragment_add | |||
| 867 | * call set the reassembled length based on the fragment offset and | |||
| 868 | * length. As the length is known now, be sure to disable that magic. | |||
| 869 | */ | |||
| 870 | fd_head->flags &= ~FD_PARTIAL_REASSEMBLY0x0040; | |||
| 871 | ||||
| 872 | /* If the length is already as expected, there is nothing else to do. */ | |||
| 873 | if (tot_len == fd_head->datalen) | |||
| 874 | return; | |||
| 875 | ||||
| 876 | if (fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 877 | /* | |||
| 878 | * Fragments were reassembled before, clear it to allow | |||
| 879 | * increasing the reassembled length. | |||
| 880 | */ | |||
| 881 | fragment_reset_defragmentation(fd_head); | |||
| 882 | } | |||
| 883 | ||||
| 884 | fd_head->datalen = tot_len; | |||
| 885 | fd_head->flags |= FD_DATALEN_SET0x0400; | |||
| 886 | } | |||
| 887 | ||||
| 888 | void | |||
| 889 | fragment_truncate(reassembly_table *table, const packet_info *pinfo, | |||
| 890 | const uint32_t id, const void *data, const uint32_t tot_len) | |||
| 891 | ||||
| 892 | { | |||
| 893 | tvbuff_t *old_tvb_data; | |||
| 894 | fragment_head *fd_head; | |||
| 895 | ||||
| 896 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 897 | if (!fd_head) | |||
| 898 | return; | |||
| 899 | ||||
| 900 | /* Caller must ensure that this function is only called when | |||
| 901 | * we are defragmented. */ | |||
| 902 | DISSECTOR_ASSERT(fd_head->flags & FD_DEFRAGMENTED)((void) ((fd_head->flags & 0x0001) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 902, "fd_head->flags & 0x0001" )))); | |||
| 903 | ||||
| 904 | /* | |||
| 905 | * If FD_PARTIAL_REASSEMBLY is set, it would make the next fragment_add | |||
| 906 | * call set the reassembled length based on the fragment offset and | |||
| 907 | * length. As the length is known now, be sure to disable that magic. | |||
| 908 | */ | |||
| 909 | fd_head->flags &= ~FD_PARTIAL_REASSEMBLY0x0040; | |||
| 910 | ||||
| 911 | /* If the length is already as expected, there is nothing else to do. */ | |||
| 912 | if (tot_len == fd_head->datalen) | |||
| 913 | return; | |||
| 914 | ||||
| 915 | DISSECTOR_ASSERT(fd_head->datalen > tot_len)((void) ((fd_head->datalen > tot_len) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 915, "fd_head->datalen > tot_len" )))); | |||
| 916 | ||||
| 917 | old_tvb_data=fd_head->tvb_data; | |||
| 918 | fd_head->tvb_data = tvb_clone_offset_len(old_tvb_data, 0, tot_len); | |||
| 919 | tvb_set_free_cb(fd_head->tvb_data, g_free); | |||
| 920 | ||||
| 921 | if (old_tvb_data) | |||
| 922 | tvb_add_to_chain(fd_head->tvb_data, old_tvb_data); | |||
| 923 | fd_head->datalen = tot_len; | |||
| 924 | ||||
| 925 | /* Keep the fragments before the split point, dividing any if | |||
| 926 | * necessary. | |||
| 927 | * XXX: In rare cases, there might be fragments marked as overlap that | |||
| 928 | * have data both before and after the split point, and which only | |||
| 929 | * overlap after the split point. In that case, after dividing the | |||
| 930 | * fragments the first part no longer overlap. | |||
| 931 | * However, at this point we can't test for overlap conflicts, | |||
| 932 | * so we'll just leave the overlap flags as-is. | |||
| 933 | */ | |||
| 934 | fd_head->flags &= ~(FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004|FD_TOOLONGFRAGMENT0x0010|FD_MULTIPLETAILS0x0008); | |||
| 935 | fragment_item *fd_i, *prev_fd = NULL((void*)0); | |||
| 936 | for (fd_i = fd_head->next; fd_i && (fd_i->offset < tot_len); fd_i = fd_i->next) { | |||
| 937 | fd_i->flags &= ~(FD_TOOLONGFRAGMENT0x0010|FD_MULTIPLETAILS0x0008); | |||
| 938 | /* Check for the split point occurring in the middle of the | |||
| 939 | * fragment. */ | |||
| 940 | if (fd_i->offset + fd_i->len > tot_len) { | |||
| 941 | fd_i->len = tot_len - fd_i->offset; | |||
| 942 | } | |||
| 943 | fd_head->flags |= fd_i->flags & (FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004); | |||
| 944 | prev_fd = fd_i; | |||
| 945 | ||||
| 946 | /* Below should do nothing since this is already defragmented */ | |||
| 947 | fragment_item_free_tvb(fd_i); | |||
| 948 | } | |||
| 949 | ||||
| 950 | /* Remove all the other fragments, as they are past the split point. */ | |||
| 951 | if (prev_fd) { | |||
| 952 | prev_fd->next = NULL((void*)0); | |||
| 953 | } else { | |||
| 954 | fd_head->next = NULL((void*)0); | |||
| 955 | } | |||
| 956 | fd_head->contiguous_len = MIN(fd_head->contiguous_len, tot_len)(((fd_head->contiguous_len) < (tot_len)) ? (fd_head-> contiguous_len) : (tot_len)); | |||
| 957 | fragment_items_removed(fd_head, prev_fd); | |||
| 958 | while (fd_i != NULL((void*)0)) { | |||
| 959 | fd_i = fragment_item_free(fd_i); | |||
| 960 | } | |||
| 961 | } | |||
| 962 | ||||
| 963 | uint32_t | |||
| 964 | fragment_get_tot_len(reassembly_table *table, const packet_info *pinfo, | |||
| 965 | const uint32_t id, const void *data) | |||
| 966 | { | |||
| 967 | fragment_head *fd_head; | |||
| 968 | ||||
| 969 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 970 | ||||
| 971 | if(fd_head){ | |||
| 972 | return fd_head->datalen; | |||
| 973 | } | |||
| 974 | ||||
| 975 | return 0; | |||
| 976 | } | |||
| 977 | ||||
| 978 | /* This function will set the partial reassembly flag for a fh. | |||
| 979 | When this function is called, the fh MUST already exist, i.e. | |||
| 980 | the fh MUST be created by the initial call to fragment_add() before | |||
| 981 | this function is called. | |||
| 982 | Also note that this function MUST be called to indicate a fh will be | |||
| 983 | extended (increase the already stored data) | |||
| 984 | */ | |||
| 985 | ||||
| 986 | void | |||
| 987 | fragment_set_partial_reassembly(reassembly_table *table, | |||
| 988 | const packet_info *pinfo, const uint32_t id, | |||
| 989 | const void *data) | |||
| 990 | { | |||
| 991 | fragment_head *fd_head; | |||
| 992 | ||||
| 993 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 994 | ||||
| 995 | /* | |||
| 996 | * XXX - why not do all the stuff done early in "fragment_add_work()", | |||
| 997 | * turning off FD_DEFRAGMENTED and pointing the fragments' data | |||
| 998 | * pointers to the appropriate part of the already-reassembled | |||
| 999 | * data, and clearing the data length and "reassembled in" frame | |||
| 1000 | * number, here? We currently have a hack in the TCP dissector | |||
| 1001 | * not to set the "reassembled in" value if the "partial reassembly" | |||
| 1002 | * flag is set, so that in the first pass through the packets | |||
| 1003 | * we don't falsely set a packet as reassembled in that packet | |||
| 1004 | * if the dissector decided that even more reassembly was needed. | |||
| 1005 | */ | |||
| 1006 | if(fd_head){ | |||
| 1007 | fd_head->flags |= FD_PARTIAL_REASSEMBLY0x0040; | |||
| 1008 | } | |||
| 1009 | } | |||
| 1010 | ||||
| 1011 | /* | |||
| 1012 | * This function gets rid of an entry from a fragment table, given | |||
| 1013 | * a pointer to the key for that entry. | |||
| 1014 | * | |||
| 1015 | * The key freeing routine will be called by g_hash_table_remove(). | |||
| 1016 | */ | |||
| 1017 | static void | |||
| 1018 | fragment_unhash(reassembly_table *table, void *key) | |||
| 1019 | { | |||
| 1020 | /* | |||
| 1021 | * Remove the entry from the fragment table. | |||
| 1022 | */ | |||
| 1023 | g_hash_table_remove(table->fragment_table, key); | |||
| 1024 | } | |||
| 1025 | ||||
| 1026 | /* | |||
| 1027 | * This function adds fragment_head structure to a reassembled-packet | |||
| 1028 | * hash table, using the frame numbers of each of the frames from | |||
| 1029 | * which it was reassembled as keys, and sets the "reassembled_in" | |||
| 1030 | * frame number. | |||
| 1031 | */ | |||
| 1032 | static void | |||
| 1033 | fragment_reassembled(reassembly_table *table, fragment_head *fd_head, | |||
| 1034 | const packet_info *pinfo, const uint32_t id) | |||
| 1035 | { | |||
| 1036 | reassembled_key *new_key; | |||
| 1037 | fragment_item *fd; | |||
| 1038 | ||||
| 1039 | fd_head->ref_count = 0; | |||
| 1040 | if (fd_head->next == NULL((void*)0)) { | |||
| 1041 | /* | |||
| 1042 | * This was not fragmented, so there's no fragment | |||
| 1043 | * table; just hash it using the current frame number. | |||
| 1044 | */ | |||
| 1045 | new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc (sizeof (reassembled_key))); | |||
| 1046 | new_key->frame = pinfo->num; | |||
| 1047 | new_key->id = id; | |||
| 1048 | reassembled_table_insert(table->reassembled_table, new_key, fd_head); | |||
| 1049 | } else { | |||
| 1050 | /* | |||
| 1051 | * Hash it with the frame numbers for all the frames. | |||
| 1052 | */ | |||
| 1053 | for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){ | |||
| 1054 | new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc (sizeof (reassembled_key))); | |||
| 1055 | new_key->frame = fd->frame; | |||
| 1056 | new_key->id = id; | |||
| 1057 | reassembled_table_insert(table->reassembled_table, new_key, fd_head); | |||
| 1058 | } | |||
| 1059 | } | |||
| 1060 | fd_head->flags |= FD_DEFRAGMENTED0x0001; | |||
| 1061 | fd_head->reassembled_in = pinfo->num; | |||
| 1062 | fd_head->reas_in_layer_num = pinfo->curr_layer_num; | |||
| 1063 | } | |||
| 1064 | ||||
| 1065 | /* | |||
| 1066 | * This function is a variant of the above for the single sequence | |||
| 1067 | * case, using id+offset (i.e., the original sequence number) for the id | |||
| 1068 | * in the key. | |||
| 1069 | */ | |||
| 1070 | static void | |||
| 1071 | fragment_reassembled_single(reassembly_table *table, fragment_head *fd_head, | |||
| 1072 | const packet_info *pinfo, const uint32_t id) | |||
| 1073 | { | |||
| 1074 | reassembled_key *new_key; | |||
| 1075 | fragment_item *fd; | |||
| 1076 | ||||
| 1077 | fd_head->ref_count = 0; | |||
| 1078 | if (fd_head->next == NULL((void*)0)) { | |||
| 1079 | /* | |||
| 1080 | * This was not fragmented, so there's no fragment | |||
| 1081 | * table; just hash it using the current frame number. | |||
| 1082 | */ | |||
| 1083 | new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc (sizeof (reassembled_key))); | |||
| 1084 | new_key->frame = pinfo->num; | |||
| 1085 | new_key->id = id; | |||
| 1086 | reassembled_table_insert(table->reassembled_table, new_key, fd_head); | |||
| 1087 | } else { | |||
| 1088 | /* | |||
| 1089 | * Hash it with the frame numbers for all the frames. | |||
| 1090 | */ | |||
| 1091 | for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){ | |||
| 1092 | new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc (sizeof (reassembled_key))); | |||
| 1093 | new_key->frame = fd->frame; | |||
| 1094 | new_key->id = id + fd->offset; | |||
| 1095 | reassembled_table_insert(table->reassembled_table, new_key, fd_head); | |||
| 1096 | } | |||
| 1097 | } | |||
| 1098 | fd_head->flags |= FD_DEFRAGMENTED0x0001; | |||
| 1099 | fd_head->reassembled_in = pinfo->num; | |||
| 1100 | fd_head->reas_in_layer_num = pinfo->curr_layer_num; | |||
| 1101 | } | |||
| 1102 | ||||
| 1103 | static void | |||
| 1104 | LINK_FRAG(fragment_head *fd_head,fragment_item *fd) | |||
| 1105 | { | |||
| 1106 | fragment_item *fd_i; | |||
| 1107 | ||||
| 1108 | /* add fragment to list, keep list sorted */ | |||
| 1109 | if (fd_head->next == NULL((void*)0) || fd->offset < fd_head->next->offset) { | |||
| 1110 | /* New first fragment */ | |||
| 1111 | fd->next = fd_head->next; | |||
| 1112 | fd_head->next = fd; | |||
| 1113 | } else { | |||
| 1114 | fd_i = fd_head->next; | |||
| 1115 | if (fd_head->first_gap != NULL((void*)0)) { | |||
| 1116 | if (fd->offset >= fd_head->first_gap->offset) { | |||
| 1117 | /* fragment is after first gap */ | |||
| 1118 | fd_i = fd_head->first_gap; | |||
| 1119 | } | |||
| 1120 | } | |||
| 1121 | for(; fd_i->next; fd_i=fd_i->next) { | |||
| 1122 | if (fd->offset < fd_i->next->offset ) | |||
| 1123 | break; | |||
| 1124 | } | |||
| 1125 | fd->next = fd_i->next; | |||
| 1126 | fd_i->next = fd; | |||
| 1127 | } | |||
| 1128 | ||||
| 1129 | update_first_gap(fd_head, fd, false0); | |||
| 1130 | } | |||
| 1131 | ||||
| 1132 | static void | |||
| 1133 | MERGE_FRAG(fragment_head *fd_head, fragment_item *fd) | |||
| 1134 | { | |||
| 1135 | fragment_item *fd_i, *tmp, *inserted = fd; | |||
| 1136 | bool_Bool multi_insert; | |||
| 1137 | ||||
| 1138 | if (fd == NULL((void*)0)) return; | |||
| 1139 | ||||
| 1140 | multi_insert = (fd->next != NULL((void*)0)); | |||
| 1141 | ||||
| 1142 | if (fd_head->next == NULL((void*)0)) { | |||
| 1143 | fd_head->next = fd; | |||
| 1144 | update_first_gap(fd_head, fd, multi_insert); | |||
| 1145 | return; | |||
| 1146 | } | |||
| 1147 | ||||
| 1148 | if ((fd_head->first_gap != NULL((void*)0)) && | |||
| 1149 | (fd->offset >= fd_head->first_gap->offset)) { | |||
| 1150 | /* all new fragments go after first gap */ | |||
| 1151 | fd_i = fd_head->first_gap; | |||
| 1152 | } else { | |||
| 1153 | /* at least one new fragment goes before first gap */ | |||
| 1154 | if (fd->offset < fd_head->next->offset) { | |||
| 1155 | /* inserted fragment is new head, "swap" the lists */ | |||
| 1156 | tmp = fd_head->next; | |||
| 1157 | fd_head->next = fd; | |||
| 1158 | fd = tmp; | |||
| 1159 | } | |||
| 1160 | fd_i = fd_head->next; | |||
| 1161 | } | |||
| 1162 | ||||
| 1163 | /* Traverse the list linked to fragment head ("main" list), checking if | |||
| 1164 | * fd pointer ("merge" list) should go before or after fd_i->next. Swap | |||
| 1165 | * fd_i->next ("main") and fd pointers ("merge") if "merge" list should | |||
| 1166 | * go before iterated element (fd_i). After the swap what formerly was | |||
| 1167 | * "merge" list essentially becomes part of "main" list (just detached | |||
| 1168 | * element, i.e. fd, is now head of new "merge list"). | |||
| 1169 | */ | |||
| 1170 | for(; fd_i->next; fd_i=fd_i->next) { | |||
| 1171 | if (fd->offset < fd_i->next->offset) { | |||
| 1172 | tmp = fd_i->next; | |||
| 1173 | fd_i->next = fd; | |||
| 1174 | fd = tmp; | |||
| 1175 | } | |||
| 1176 | } | |||
| 1177 | /* Reached "main" list end, attach remaining elements */ | |||
| 1178 | fd_i->next = fd; | |||
| 1179 | ||||
| 1180 | update_first_gap(fd_head, inserted, multi_insert); | |||
| 1181 | } | |||
| 1182 | ||||
| 1183 | /* | |||
| 1184 | * This function adds a new fragment to the fragment hash table. | |||
| 1185 | * If this is the first fragment seen for this datagram, a new entry | |||
| 1186 | * is created in the hash table, otherwise this fragment is just added | |||
| 1187 | * to the linked list of fragments for this packet. | |||
| 1188 | * The list of fragments for a specific datagram is kept sorted for | |||
| 1189 | * easier handling. | |||
| 1190 | * | |||
| 1191 | * Returns a pointer to the head of the fragment data list if we have all the | |||
| 1192 | * fragments, NULL otherwise. | |||
| 1193 | * | |||
| 1194 | * This function assumes frag_offset being a byte offset into the defragment | |||
| 1195 | * packet. | |||
| 1196 | * | |||
| 1197 | * 01-2002 | |||
| 1198 | * Once the fh is defragmented (= FD_DEFRAGMENTED set), it can be | |||
| 1199 | * extended using the FD_PARTIAL_REASSEMBLY flag. This flag should be set | |||
| 1200 | * using fragment_set_partial_reassembly() before calling fragment_add | |||
| 1201 | * with the new fragment. FD_TOOLONGFRAGMENT and FD_MULTIPLETAILS flags | |||
| 1202 | * are lowered when a new extension process is started. | |||
| 1203 | */ | |||
| 1204 | static bool_Bool | |||
| 1205 | fragment_add_work(fragment_head *fd_head, tvbuff_t *tvb, const int offset, | |||
| 1206 | const packet_info *pinfo, const uint32_t frag_offset, | |||
| 1207 | const uint32_t frag_data_len, const bool_Bool more_frags, | |||
| 1208 | const uint32_t frag_frame, const bool_Bool allow_overlaps) | |||
| 1209 | { | |||
| 1210 | fragment_item *fd; | |||
| 1211 | fragment_item *fd_i; | |||
| 1212 | uint32_t dfpos, fraglen, overlap; | |||
| 1213 | tvbuff_t *old_tvb_data; | |||
| 1214 | uint8_t *data; | |||
| 1215 | ||||
| 1216 | /* create new fd describing this fragment */ | |||
| 1217 | fd = new_fragment_item(frag_frame, frag_offset, frag_data_len); | |||
| 1218 | ||||
| 1219 | /* | |||
| 1220 | * Are we adding to an already-completed reassembly? | |||
| 1221 | */ | |||
| 1222 | if (fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 1223 | /* | |||
| 1224 | * Yes. Does this fragment go past the end of the results | |||
| 1225 | * of that reassembly? | |||
| 1226 | */ | |||
| 1227 | if (frag_offset + frag_data_len > fd_head->datalen) { | |||
| 1228 | /* | |||
| 1229 | * Yes. Have we been requested to continue reassembly? | |||
| 1230 | */ | |||
| 1231 | if (fd_head->flags & FD_PARTIAL_REASSEMBLY0x0040) { | |||
| 1232 | /* | |||
| 1233 | * Yes. Set flag in already empty fds & | |||
| 1234 | * point old fds to malloc'ed data. | |||
| 1235 | */ | |||
| 1236 | fragment_reset_defragmentation(fd_head); | |||
| 1237 | } else if (!allow_overlaps) { | |||
| 1238 | /* | |||
| 1239 | * No. Bail out since we have no idea what to | |||
| 1240 | * do with this fragment (and if we keep going | |||
| 1241 | * we'll run past the end of a buffer sooner | |||
| 1242 | * or later). | |||
| 1243 | */ | |||
| 1244 | g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else (void) ((fragment_item*) 0 == (fd)); } while (0); | |||
| 1245 | ||||
| 1246 | /* | |||
| 1247 | * This is an attempt to add a fragment to a | |||
| 1248 | * reassembly that had already completed. | |||
| 1249 | * If it had no error, we don't want to | |||
| 1250 | * mark it with an error, and if it had an | |||
| 1251 | * error, we don't want to overwrite it, so | |||
| 1252 | * we don't set fd_head->error. | |||
| 1253 | */ | |||
| 1254 | if (frag_offset >= fd_head->datalen) { | |||
| 1255 | /* | |||
| 1256 | * The fragment starts past the end | |||
| 1257 | * of the reassembled data. | |||
| 1258 | */ | |||
| 1259 | THROW_MESSAGE(ReassemblyError, "New fragment past old data limits")except_throw(1, (9), ("New fragment past old data limits")); | |||
| 1260 | } else { | |||
| 1261 | /* | |||
| 1262 | * The fragment starts before the end | |||
| 1263 | * of the reassembled data, but | |||
| 1264 | * runs past the end. That could | |||
| 1265 | * just be a retransmission with extra | |||
| 1266 | * data, but the calling dissector | |||
| 1267 | * didn't set FD_PARTIAL_REASSEMBLY | |||
| 1268 | * so it won't be handled correctly. | |||
| 1269 | * | |||
| 1270 | * XXX: We could set FD_TOOLONGFRAGMENT | |||
| 1271 | * below instead. | |||
| 1272 | */ | |||
| 1273 | THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)" )); | |||
| 1274 | } | |||
| 1275 | } | |||
| 1276 | } else { | |||
| 1277 | /* | |||
| 1278 | * No. That means it overlaps the completed reassembly. | |||
| 1279 | * This is probably a retransmission and normal | |||
| 1280 | * behavior. (If not, it's because the dissector | |||
| 1281 | * doesn't handle reused sequence numbers correctly, | |||
| 1282 | * e.g. #10503). Handle below. | |||
| 1283 | */ | |||
| 1284 | } | |||
| 1285 | } | |||
| 1286 | ||||
| 1287 | /* Do this after we may have bailed out (above) so that we don't leave | |||
| 1288 | * fd_head->frame in a bad state if we do */ | |||
| 1289 | if (fd->frame > fd_head->frame) | |||
| 1290 | fd_head->frame = fd->frame; | |||
| 1291 | ||||
| 1292 | if (!more_frags) { | |||
| 1293 | /* | |||
| 1294 | * This is the tail fragment in the sequence. | |||
| 1295 | */ | |||
| 1296 | if (fd_head->flags & FD_DATALEN_SET0x0400) { | |||
| 1297 | /* ok we have already seen other tails for this packet | |||
| 1298 | * it might be a duplicate. | |||
| 1299 | */ | |||
| 1300 | if (fd_head->datalen != (fd->offset + fd->len) ){ | |||
| 1301 | /* Oops, this tail indicates a different packet | |||
| 1302 | * len than the previous ones. Something's wrong. | |||
| 1303 | */ | |||
| 1304 | fd->flags |= FD_MULTIPLETAILS0x0008; | |||
| 1305 | fd_head->flags |= FD_MULTIPLETAILS0x0008; | |||
| 1306 | } | |||
| 1307 | } else { | |||
| 1308 | /* This was the first tail fragment; now we know | |||
| 1309 | * what the length of the packet should be. | |||
| 1310 | */ | |||
| 1311 | fd_head->datalen = fd->offset + fd->len; | |||
| 1312 | fd_head->flags |= FD_DATALEN_SET0x0400; | |||
| 1313 | } | |||
| 1314 | } | |||
| 1315 | ||||
| 1316 | ||||
| 1317 | ||||
| 1318 | /* If the packet is already defragmented, this MUST be an overlap. | |||
| 1319 | * The entire defragmented packet is in fd_head->data. | |||
| 1320 | * Even if we have previously defragmented this packet, we still | |||
| 1321 | * check it. Someone might play overlap and TTL games. | |||
| 1322 | */ | |||
| 1323 | if (fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 1324 | uint32_t end_offset = fd->offset + fd->len; | |||
| 1325 | fd->flags |= FD_OVERLAP0x0002; | |||
| 1326 | fd_head->flags |= FD_OVERLAP0x0002; | |||
| 1327 | /* make sure it's not too long */ | |||
| 1328 | /* XXX: We probably don't call this, unlike the _seq() | |||
| 1329 | * functions, because we throw an exception above. | |||
| 1330 | */ | |||
| 1331 | if (end_offset > fd_head->datalen || end_offset < fd->offset || end_offset < fd->len) { | |||
| 1332 | fd->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 1333 | fd_head->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 1334 | } | |||
| 1335 | /* make sure it doesn't conflict with previous data */ | |||
| 1336 | else if ( tvb_memeql(fd_head->tvb_data, fd->offset, | |||
| 1337 | tvb_get_ptr(tvb,offset,fd->len),fd->len) ){ | |||
| 1338 | fd->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 1339 | fd_head->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 1340 | } | |||
| 1341 | /* it was just an overlap, link it and return */ | |||
| 1342 | LINK_FRAG(fd_head,fd); | |||
| 1343 | return true1; | |||
| 1344 | } | |||
| 1345 | ||||
| 1346 | ||||
| 1347 | ||||
| 1348 | /* If we have reached this point, the packet is not defragmented yet. | |||
| 1349 | * Save all payload in a buffer until we can defragment. | |||
| 1350 | */ | |||
| 1351 | if (!tvb_bytes_exist(tvb, offset, fd->len)) { | |||
| 1352 | g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else (void) ((fragment_item*) 0 == (fd)); } while (0); | |||
| 1353 | THROW(BoundsError)except_throw(1, (1), ((void*)0)); | |||
| 1354 | } | |||
| 1355 | fd->tvb_data = tvb_clone_offset_len(tvb, offset, fd->len); | |||
| 1356 | LINK_FRAG(fd_head,fd); | |||
| 1357 | ||||
| 1358 | ||||
| 1359 | if( !(fd_head->flags & FD_DATALEN_SET0x0400) ){ | |||
| 1360 | /* if we don't know the datalen, there are still missing | |||
| 1361 | * packets. Cheaper than the check below. | |||
| 1362 | */ | |||
| 1363 | return false0; | |||
| 1364 | } | |||
| 1365 | ||||
| 1366 | /* Check if we have received the entire fragment. */ | |||
| 1367 | if (fd_head->contiguous_len < fd_head->datalen) { | |||
| 1368 | /* | |||
| 1369 | * The amount of contiguous data we have is less than the | |||
| 1370 | * amount of data we're trying to reassemble, so we haven't | |||
| 1371 | * received all packets yet. | |||
| 1372 | */ | |||
| 1373 | return false0; | |||
| 1374 | } | |||
| 1375 | ||||
| 1376 | /* we have received an entire packet, defragment it and | |||
| 1377 | * free all fragments | |||
| 1378 | */ | |||
| 1379 | /* store old data just in case */ | |||
| 1380 | old_tvb_data=fd_head->tvb_data; | |||
| 1381 | data = (uint8_t *) g_malloc(fd_head->datalen); | |||
| 1382 | fd_head->tvb_data = tvb_new_real_data(data, fd_head->datalen, fd_head->datalen); | |||
| 1383 | tvb_set_free_cb(fd_head->tvb_data, g_free); | |||
| 1384 | ||||
| 1385 | /* add all data fragments */ | |||
| 1386 | for (dfpos=0,fd_i=fd_head->next;fd_i;fd_i=fd_i->next) { | |||
| 1387 | if (fd_i->len) { | |||
| 1388 | /* | |||
| 1389 | * The contiguous length check above also | |||
| 1390 | * ensures that the only gaps that exist here | |||
| 1391 | * are ones where a fragment starts past the | |||
| 1392 | * end of the reassembled datagram, and there's | |||
| 1393 | * a gap between the previous fragment and | |||
| 1394 | * that fragment. | |||
| 1395 | * | |||
| 1396 | * A "DESEGMENT_UNTIL_FIN" was involved wherein the | |||
| 1397 | * FIN packet had an offset less than the highest | |||
| 1398 | * fragment offset seen. [Seen from a fuzz-test: | |||
| 1399 | * bug #2470]). | |||
| 1400 | * | |||
| 1401 | * Note that the "overlap" compare must only be | |||
| 1402 | * done for fragments with (offset+len) <= fd_head->datalen | |||
| 1403 | * and thus within the newly g_malloc'd buffer. | |||
| 1404 | */ | |||
| 1405 | ||||
| 1406 | if (fd_i->offset >= fd_head->datalen) { | |||
| 1407 | /* | |||
| 1408 | * Fragment starts after the end | |||
| 1409 | * of the reassembled packet. | |||
| 1410 | * | |||
| 1411 | * This can happen if the length was | |||
| 1412 | * set after the offending fragment | |||
| 1413 | * was added to the reassembly. | |||
| 1414 | * | |||
| 1415 | * Flag this fragment, but don't | |||
| 1416 | * try to extract any data from | |||
| 1417 | * it, as there's no place to put | |||
| 1418 | * it. | |||
| 1419 | * | |||
| 1420 | * XXX - add different flag value | |||
| 1421 | * for this. | |||
| 1422 | */ | |||
| 1423 | fd_i->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 1424 | fd_head->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 1425 | } else if (fd_i->offset + fd_i->len < fd_i->offset) { | |||
| 1426 | /* Integer overflow, unhandled by rest of | |||
| 1427 | * code so error out. This check handles | |||
| 1428 | * all possible remaining overflows. | |||
| 1429 | */ | |||
| 1430 | fd_head->error = "offset + len < offset"; | |||
| 1431 | } else if (!fd_i->tvb_data) { | |||
| 1432 | fd_head->error = "no data"; | |||
| 1433 | } else { | |||
| 1434 | fraglen = fd_i->len; | |||
| 1435 | if (fd_i->offset + fraglen > fd_head->datalen) { | |||
| 1436 | /* | |||
| 1437 | * Fragment goes past the end | |||
| 1438 | * of the packet, as indicated | |||
| 1439 | * by the last fragment. | |||
| 1440 | * | |||
| 1441 | * This can happen if the | |||
| 1442 | * length was set after the | |||
| 1443 | * offending fragment was | |||
| 1444 | * added to the reassembly. | |||
| 1445 | * | |||
| 1446 | * Mark it as such, and only | |||
| 1447 | * copy from it what fits in | |||
| 1448 | * the packet. | |||
| 1449 | */ | |||
| 1450 | fd_i->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 1451 | fd_head->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 1452 | fraglen = fd_head->datalen - fd_i->offset; | |||
| 1453 | } | |||
| 1454 | overlap = dfpos - fd_i->offset; | |||
| 1455 | /* Guaranteed to be >= 0, previous code | |||
| 1456 | * has checked for gaps. */ | |||
| 1457 | if (overlap) { | |||
| 1458 | /* duplicate/retransmission/overlap */ | |||
| 1459 | uint32_t cmp_len = MIN(fd_i->len,overlap)(((fd_i->len) < (overlap)) ? (fd_i->len) : (overlap) ); | |||
| 1460 | ||||
| 1461 | fd_i->flags |= FD_OVERLAP0x0002; | |||
| 1462 | fd_head->flags |= FD_OVERLAP0x0002; | |||
| 1463 | if ( memcmp(data + fd_i->offset, | |||
| 1464 | tvb_get_ptr(fd_i->tvb_data, 0, cmp_len), | |||
| 1465 | cmp_len) | |||
| 1466 | ) { | |||
| 1467 | fd_i->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 1468 | fd_head->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 1469 | } | |||
| 1470 | } | |||
| 1471 | /* XXX: As in the fragment_add_seq funcs | |||
| 1472 | * like fragment_defragment_and_free() the | |||
| 1473 | * existing behavior does not overwrite | |||
| 1474 | * overlapping bytes even if there is a | |||
| 1475 | * conflict. It only adds new bytes. | |||
| 1476 | * | |||
| 1477 | * Since we only add fragments to a reassembly | |||
| 1478 | * if the reassembly isn't complete, the most | |||
| 1479 | * common case for overlap conflicts is when | |||
| 1480 | * an earlier reassembly isn't fully contained | |||
| 1481 | * in the capture, and we've reused an | |||
| 1482 | * identification number / wrapped around | |||
| 1483 | * offset sequence numbers much later in the | |||
| 1484 | * capture. In that case, we probably *do* | |||
| 1485 | * want to overwrite conflicting bytes, since | |||
| 1486 | * the earlier fragments didn't form a complete | |||
| 1487 | * reassembly and should be effectively thrown | |||
| 1488 | * out rather than mixed with the new ones? | |||
| 1489 | */ | |||
| 1490 | if (fd_i->offset + fraglen > dfpos) { | |||
| 1491 | memcpy(data+dfpos, | |||
| 1492 | tvb_get_ptr(fd_i->tvb_data, overlap, fraglen-overlap), | |||
| 1493 | fraglen-overlap); | |||
| 1494 | dfpos = fd_i->offset + fraglen; | |||
| 1495 | } | |||
| 1496 | } | |||
| 1497 | ||||
| 1498 | fragment_item_free_tvb(fd_i); | |||
| 1499 | } | |||
| 1500 | } | |||
| 1501 | ||||
| 1502 | if (old_tvb_data) | |||
| 1503 | tvb_add_to_chain(tvb, old_tvb_data); | |||
| 1504 | /* mark this packet as defragmented. | |||
| 1505 | allows us to skip any trailing fragments */ | |||
| 1506 | fd_head->flags |= FD_DEFRAGMENTED0x0001; | |||
| 1507 | fd_head->reassembled_in=pinfo->num; | |||
| 1508 | fd_head->reas_in_layer_num = pinfo->curr_layer_num; | |||
| 1509 | ||||
| 1510 | /* we don't throw until here to avoid leaking old_data and others */ | |||
| 1511 | if (fd_head->error) { | |||
| 1512 | THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error)); | |||
| 1513 | } | |||
| 1514 | ||||
| 1515 | return true1; | |||
| 1516 | } | |||
| 1517 | ||||
| 1518 | static fragment_head * | |||
| 1519 | fragment_add_common(reassembly_table *table, tvbuff_t *tvb, const int offset, | |||
| 1520 | const packet_info *pinfo, const uint32_t id, | |||
| 1521 | const void *data, const uint32_t frag_offset, | |||
| 1522 | const uint32_t frag_data_len, const bool_Bool more_frags, | |||
| 1523 | const bool_Bool check_already_added, | |||
| 1524 | const uint32_t frag_frame) | |||
| 1525 | { | |||
| 1526 | fragment_head *fd_head; | |||
| 1527 | fragment_item *fd_item; | |||
| 1528 | bool_Bool already_added; | |||
| 1529 | ||||
| 1530 | ||||
| 1531 | /* | |||
| 1532 | * Dissector shouldn't give us garbage tvb info. | |||
| 1533 | * | |||
| 1534 | * XXX - should this code take responsibility for preventing | |||
| 1535 | * reassembly if data is missing due to the packets being | |||
| 1536 | * sliced, rather than leaving it up to dissectors? | |||
| 1537 | */ | |||
| 1538 | DISSECTOR_ASSERT(tvb_bytes_exist(tvb, offset, frag_data_len))((void) ((tvb_bytes_exist(tvb, offset, frag_data_len)) ? (void )0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\"" , "epan/reassemble.c", 1538, "tvb_bytes_exist(tvb, offset, frag_data_len)" )))); | |||
| 1539 | ||||
| 1540 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 1541 | ||||
| 1542 | #if 0 | |||
| 1543 | /* debug output of associated fragments. */ | |||
| 1544 | /* leave it here for future debugging sessions */ | |||
| 1545 | if(strcmp(pinfo->current_proto, "DCERPC") == 0) { | |||
| 1546 | printf("proto:%s num:%u id:%u offset:%u len:%u more:%u visited:%u\n", | |||
| 1547 | pinfo->current_proto, pinfo->num, id, frag_offset, frag_data_len, more_frags, pinfo->fd->visited); | |||
| 1548 | if(fd_head != NULL((void*)0)) { | |||
| 1549 | for(fd_item=fd_head->next;fd_item;fd_item=fd_item->next){ | |||
| 1550 | printf("fd_frame:%u fd_offset:%u len:%u datalen:%u\n", | |||
| 1551 | fd_item->frame, fd_item->offset, fd_item->len, fd_item->datalen); | |||
| 1552 | } | |||
| 1553 | } | |||
| 1554 | } | |||
| 1555 | #endif | |||
| 1556 | ||||
| 1557 | /* | |||
| 1558 | * Is this the first pass through the capture? | |||
| 1559 | */ | |||
| 1560 | if (!pinfo->fd->visited) { | |||
| 1561 | /* | |||
| 1562 | * Yes, so we could be doing reassembly. If | |||
| 1563 | * "check_already_added" is true, and fd_head is non-null, | |||
| 1564 | * meaning that this fragment would be added to an | |||
| 1565 | * in-progress reassembly, check if we have seen this | |||
| 1566 | * fragment before, i.e., if we have already added it to | |||
| 1567 | * that reassembly. That can be true even on the first pass | |||
| 1568 | * since we sometimes might call a subdissector multiple | |||
| 1569 | * times. | |||
| 1570 | * | |||
| 1571 | * We check both the frame number and the fragment offset, | |||
| 1572 | * so that we support multiple fragments from the same | |||
| 1573 | * frame being added to the same reassembled PDU. | |||
| 1574 | */ | |||
| 1575 | if (check_already_added && fd_head != NULL((void*)0)) { | |||
| 1576 | /* | |||
| 1577 | * fd_head->frame is the maximum of the frame | |||
| 1578 | * numbers of all the fragments added to this | |||
| 1579 | * reassembly; if this frame is later than that | |||
| 1580 | * frame, we know it hasn't been added yet. | |||
| 1581 | */ | |||
| 1582 | if (frag_frame <= fd_head->frame) { | |||
| 1583 | already_added = false0; | |||
| 1584 | /* | |||
| 1585 | * The first item in the reassembly list | |||
| 1586 | * is not a fragment, it's a data structure | |||
| 1587 | * for the reassembled packet, so we | |||
| 1588 | * start checking with the next item. | |||
| 1589 | */ | |||
| 1590 | for (fd_item = fd_head->next; fd_item; | |||
| 1591 | fd_item = fd_item->next) { | |||
| 1592 | if (frag_frame == fd_item->frame && | |||
| 1593 | frag_offset == fd_item->offset) { | |||
| 1594 | already_added = true1; | |||
| 1595 | break; | |||
| 1596 | } | |||
| 1597 | } | |||
| 1598 | if (already_added) { | |||
| 1599 | /* | |||
| 1600 | * Have we already finished | |||
| 1601 | * reassembling? | |||
| 1602 | */ | |||
| 1603 | if (fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 1604 | /* | |||
| 1605 | * Yes. | |||
| 1606 | * XXX - can this ever happen? | |||
| 1607 | */ | |||
| 1608 | THROW_MESSAGE(ReassemblyError,except_throw(1, (9), ("Frame already added in first pass")) | |||
| 1609 | "Frame already added in first pass")except_throw(1, (9), ("Frame already added in first pass")); | |||
| 1610 | } else { | |||
| 1611 | /* | |||
| 1612 | * No. | |||
| 1613 | */ | |||
| 1614 | return NULL((void*)0); | |||
| 1615 | } | |||
| 1616 | } | |||
| 1617 | } | |||
| 1618 | } | |||
| 1619 | } else { | |||
| 1620 | /* | |||
| 1621 | * No, so we've already done all the reassembly and added | |||
| 1622 | * all the fragments. Do we have a reassembly and, if so, | |||
| 1623 | * have we finished reassembling? | |||
| 1624 | */ | |||
| 1625 | if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 1626 | /* | |||
| 1627 | * Yes. This is probably being done after the | |||
| 1628 | * first pass, and we've already done the work | |||
| 1629 | * on the first pass. | |||
| 1630 | * | |||
| 1631 | * If the reassembly got a fatal error, throw that | |||
| 1632 | * error again. | |||
| 1633 | */ | |||
| 1634 | if (fd_head->error) | |||
| 1635 | THROW_MESSAGE(ReassemblyError, fd_head->error)except_throw(1, (9), (fd_head->error)); | |||
| 1636 | ||||
| 1637 | /* | |||
| 1638 | * Is it later in the capture than all of the | |||
| 1639 | * fragments in the reassembly? | |||
| 1640 | */ | |||
| 1641 | if (frag_frame > fd_head->frame) { | |||
| 1642 | /* | |||
| 1643 | * Yes, so report this as a problem, | |||
| 1644 | * possibly a retransmission. | |||
| 1645 | */ | |||
| 1646 | THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)" )); | |||
| 1647 | } | |||
| 1648 | ||||
| 1649 | /* | |||
| 1650 | * Does this fragment go past the end of the | |||
| 1651 | * results of that reassembly? | |||
| 1652 | */ | |||
| 1653 | if (frag_offset + frag_data_len > fd_head->datalen) { | |||
| 1654 | /* | |||
| 1655 | * Yes. | |||
| 1656 | */ | |||
| 1657 | if (frag_offset >= fd_head->datalen) { | |||
| 1658 | /* | |||
| 1659 | * The fragment starts past the | |||
| 1660 | * end of the reassembled data. | |||
| 1661 | */ | |||
| 1662 | THROW_MESSAGE(ReassemblyError, "New fragment past old data limits")except_throw(1, (9), ("New fragment past old data limits")); | |||
| 1663 | } else { | |||
| 1664 | /* | |||
| 1665 | * The fragment starts before the end | |||
| 1666 | * of the reassembled data, but | |||
| 1667 | * runs past the end. That could | |||
| 1668 | * just be a retransmission. | |||
| 1669 | */ | |||
| 1670 | THROW_MESSAGE(ReassemblyError, "New fragment overlaps old data (retransmission?)")except_throw(1, (9), ("New fragment overlaps old data (retransmission?)" )); | |||
| 1671 | } | |||
| 1672 | } | |||
| 1673 | ||||
| 1674 | return fd_head; | |||
| 1675 | } else { | |||
| 1676 | /* | |||
| 1677 | * No. | |||
| 1678 | */ | |||
| 1679 | return NULL((void*)0); | |||
| 1680 | } | |||
| 1681 | } | |||
| 1682 | ||||
| 1683 | if (fd_head==NULL((void*)0)){ | |||
| 1684 | /* not found, this must be the first snooped fragment for this | |||
| 1685 | * packet. Create list-head. | |||
| 1686 | */ | |||
| 1687 | fd_head = new_head(0); | |||
| 1688 | ||||
| 1689 | /* | |||
| 1690 | * Insert it into the hash table. | |||
| 1691 | */ | |||
| 1692 | insert_fd_head(table, fd_head, pinfo, id, data); | |||
| 1693 | } | |||
| 1694 | ||||
| 1695 | if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset, | |||
| 1696 | frag_data_len, more_frags, frag_frame, false0)) { | |||
| 1697 | /* | |||
| 1698 | * Reassembly is complete. | |||
| 1699 | */ | |||
| 1700 | return fd_head; | |||
| 1701 | } else { | |||
| 1702 | /* | |||
| 1703 | * Reassembly isn't complete. | |||
| 1704 | */ | |||
| 1705 | return NULL((void*)0); | |||
| 1706 | } | |||
| 1707 | } | |||
| 1708 | ||||
| 1709 | fragment_head * | |||
| 1710 | fragment_add(reassembly_table *table, tvbuff_t *tvb, const int offset, | |||
| 1711 | const packet_info *pinfo, const uint32_t id, const void *data, | |||
| 1712 | const uint32_t frag_offset, const uint32_t frag_data_len, | |||
| 1713 | const bool_Bool more_frags) | |||
| 1714 | { | |||
| 1715 | return fragment_add_common(table, tvb, offset, pinfo, id, data, | |||
| 1716 | frag_offset, frag_data_len, more_frags, true1, pinfo->num); | |||
| 1717 | } | |||
| 1718 | ||||
| 1719 | /* | |||
| 1720 | * For use when you can have multiple fragments in the same frame added | |||
| 1721 | * to the same reassembled PDU, e.g. with ONC RPC-over-TCP. | |||
| 1722 | */ | |||
| 1723 | fragment_head * | |||
| 1724 | fragment_add_multiple_ok(reassembly_table *table, tvbuff_t *tvb, | |||
| 1725 | const int offset, const packet_info *pinfo, | |||
| 1726 | const uint32_t id, const void *data, | |||
| 1727 | const uint32_t frag_offset, | |||
| 1728 | const uint32_t frag_data_len, const bool_Bool more_frags) | |||
| 1729 | { | |||
| 1730 | return fragment_add_common(table, tvb, offset, pinfo, id, data, | |||
| 1731 | frag_offset, frag_data_len, more_frags, false0, pinfo->num); | |||
| 1732 | } | |||
| 1733 | ||||
| 1734 | /* | |||
| 1735 | * For use in protocols like TCP when you are adding an out of order segment | |||
| 1736 | * that arrived in an earlier frame because the correct fragment id could not | |||
| 1737 | * be determined until later. By allowing fd->frame to be different than | |||
| 1738 | * pinfo->num, show_fragment_tree will display the correct fragment numbers. | |||
| 1739 | * | |||
| 1740 | * Note that pinfo is still used to set reassembled_in if we have all the | |||
| 1741 | * fragments, so that results on subsequent passes can be the same as the | |||
| 1742 | * first pass. | |||
| 1743 | */ | |||
| 1744 | fragment_head * | |||
| 1745 | fragment_add_out_of_order(reassembly_table *table, tvbuff_t *tvb, | |||
| 1746 | const int offset, const packet_info *pinfo, | |||
| 1747 | const uint32_t id, const void *data, | |||
| 1748 | const uint32_t frag_offset, | |||
| 1749 | const uint32_t frag_data_len, | |||
| 1750 | const bool_Bool more_frags, const uint32_t frag_frame) | |||
| 1751 | { | |||
| 1752 | return fragment_add_common(table, tvb, offset, pinfo, id, data, | |||
| 1753 | frag_offset, frag_data_len, more_frags, true1, frag_frame); | |||
| 1754 | } | |||
| 1755 | ||||
| 1756 | fragment_head * | |||
| 1757 | fragment_add_check_with_fallback(reassembly_table *table, tvbuff_t *tvb, const int offset, | |||
| 1758 | const packet_info *pinfo, const uint32_t id, | |||
| 1759 | const void *data, const uint32_t frag_offset, | |||
| 1760 | const uint32_t frag_data_len, const bool_Bool more_frags, | |||
| 1761 | const uint32_t fallback_frame) | |||
| 1762 | { | |||
| 1763 | reassembled_key reass_key; | |||
| 1764 | fragment_head *fd_head; | |||
| 1765 | void *orig_key; | |||
| 1766 | bool_Bool late_retransmission = false0; | |||
| 1767 | ||||
| 1768 | /* | |||
| 1769 | * If this isn't the first pass, look for this frame in the table | |||
| 1770 | * of reassembled packets. | |||
| 1771 | */ | |||
| 1772 | if (pinfo->fd->visited) { | |||
| 1773 | reass_key.frame = pinfo->num; | |||
| 1774 | reass_key.id = id; | |||
| 1775 | return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key); | |||
| 1776 | } | |||
| 1777 | ||||
| 1778 | /* Looks up a key in the GHashTable, returning the original key and the associated value | |||
| 1779 | * and a bool which is true if the key was found. This is useful if you need to free | |||
| 1780 | * the memory allocated for the original key, for example before calling g_hash_table_remove() | |||
| 1781 | */ | |||
| 1782 | fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key); | |||
| 1783 | if ((fd_head == NULL((void*)0)) && (fallback_frame != pinfo->num)) { | |||
| 1784 | /* Check if there is completed reassembly reachable from fallback frame */ | |||
| 1785 | reass_key.frame = fallback_frame; | |||
| 1786 | reass_key.id = id; | |||
| 1787 | fd_head = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key); | |||
| 1788 | if (fd_head != NULL((void*)0)) { | |||
| 1789 | /* Found completely reassembled packet, hash it with current frame number */ | |||
| 1790 | reassembled_key *new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc (sizeof (reassembled_key))); | |||
| 1791 | new_key->frame = pinfo->num; | |||
| 1792 | new_key->id = id; | |||
| 1793 | reassembled_table_insert(table->reassembled_table, new_key, fd_head); | |||
| 1794 | late_retransmission = true1; | |||
| 1795 | } | |||
| 1796 | } | |||
| 1797 | if (fd_head == NULL((void*)0)) { | |||
| 1798 | /* not found, this must be the first snooped fragment for this | |||
| 1799 | * packet. Create list-head. | |||
| 1800 | */ | |||
| 1801 | fd_head = new_head(0); | |||
| 1802 | ||||
| 1803 | /* | |||
| 1804 | * Save the key, for unhashing it later. | |||
| 1805 | */ | |||
| 1806 | orig_key = insert_fd_head(table, fd_head, pinfo, id, data); | |||
| 1807 | } | |||
| 1808 | ||||
| 1809 | /* | |||
| 1810 | * If this is a short frame, then we can't, and don't, do | |||
| 1811 | * reassembly on it. We just give up. | |||
| 1812 | */ | |||
| 1813 | if (!tvb_bytes_exist(tvb, offset, frag_data_len)) { | |||
| 1814 | return NULL((void*)0); | |||
| 1815 | } | |||
| 1816 | ||||
| 1817 | if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset, | |||
| 1818 | frag_data_len, more_frags, pinfo->num, late_retransmission)) { | |||
| 1819 | /* Nothing left to do if it was a late retransmission */ | |||
| 1820 | if (late_retransmission) { | |||
| 1821 | return fd_head; | |||
| 1822 | } | |||
| 1823 | /* | |||
| 1824 | * Reassembly is complete. | |||
| 1825 | * Remove this from the table of in-progress | |||
| 1826 | * reassemblies, add it to the table of | |||
| 1827 | * reassembled packets, and return it. | |||
| 1828 | */ | |||
| 1829 | ||||
| 1830 | /* | |||
| 1831 | * Remove this from the table of in-progress reassemblies, | |||
| 1832 | * and free up any memory used for it in that table. | |||
| 1833 | */ | |||
| 1834 | fragment_unhash(table, orig_key); | |||
| 1835 | ||||
| 1836 | /* | |||
| 1837 | * Add this item to the table of reassembled packets. | |||
| 1838 | */ | |||
| 1839 | fragment_reassembled(table, fd_head, pinfo, id); | |||
| 1840 | return fd_head; | |||
| 1841 | } else { | |||
| 1842 | /* | |||
| 1843 | * Reassembly isn't complete. | |||
| 1844 | */ | |||
| 1845 | return NULL((void*)0); | |||
| 1846 | } | |||
| 1847 | } | |||
| 1848 | ||||
| 1849 | fragment_head * | |||
| 1850 | fragment_add_check(reassembly_table *table, tvbuff_t *tvb, const int offset, | |||
| 1851 | const packet_info *pinfo, const uint32_t id, | |||
| 1852 | const void *data, const uint32_t frag_offset, | |||
| 1853 | const uint32_t frag_data_len, const bool_Bool more_frags) | |||
| 1854 | { | |||
| 1855 | return fragment_add_check_with_fallback(table, tvb, offset, pinfo, id, data, | |||
| 1856 | frag_offset, frag_data_len, more_frags, pinfo->num); | |||
| 1857 | } | |||
| 1858 | ||||
| 1859 | static void | |||
| 1860 | fragment_defragment_and_free (fragment_head *fd_head, const packet_info *pinfo) | |||
| 1861 | { | |||
| 1862 | fragment_item *fd_i = NULL((void*)0); | |||
| 1863 | fragment_item *last_fd = NULL((void*)0); | |||
| 1864 | uint32_t dfpos = 0, size = 0; | |||
| 1865 | tvbuff_t *old_tvb_data = NULL((void*)0); | |||
| 1866 | uint8_t *data; | |||
| 1867 | ||||
| 1868 | for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) { | |||
| 1869 | if(!last_fd || last_fd->offset!=fd_i->offset){ | |||
| 1870 | size+=fd_i->len; | |||
| 1871 | } | |||
| 1872 | last_fd=fd_i; | |||
| 1873 | } | |||
| 1874 | ||||
| 1875 | /* store old data in case the fd_i->data pointers refer to it */ | |||
| 1876 | old_tvb_data=fd_head->tvb_data; | |||
| 1877 | data = (uint8_t *) g_malloc(size); | |||
| 1878 | fd_head->tvb_data = tvb_new_real_data(data, size, size); | |||
| 1879 | tvb_set_free_cb(fd_head->tvb_data, g_free); | |||
| 1880 | fd_head->len = size; /* record size for caller */ | |||
| 1881 | ||||
| 1882 | /* add all data fragments */ | |||
| 1883 | last_fd=NULL((void*)0); | |||
| 1884 | for (fd_i=fd_head->next; fd_i; fd_i=fd_i->next) { | |||
| 1885 | if (fd_i->len) { | |||
| 1886 | if(!last_fd || last_fd->offset != fd_i->offset) { | |||
| 1887 | /* First fragment or in-sequence fragment */ | |||
| 1888 | memcpy(data+dfpos, tvb_get_ptr(fd_i->tvb_data, 0, fd_i->len), fd_i->len); | |||
| 1889 | dfpos += fd_i->len; | |||
| 1890 | } else { | |||
| 1891 | /* duplicate/retransmission/overlap */ | |||
| 1892 | fd_i->flags |= FD_OVERLAP0x0002; | |||
| 1893 | fd_head->flags |= FD_OVERLAP0x0002; | |||
| 1894 | if(last_fd->len != fd_i->len | |||
| 1895 | || tvb_memeql(last_fd->tvb_data, 0, tvb_get_ptr(fd_i->tvb_data, 0, last_fd->len), last_fd->len) ) { | |||
| 1896 | fd_i->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 1897 | fd_head->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 1898 | } | |||
| 1899 | } | |||
| 1900 | } | |||
| 1901 | last_fd=fd_i; | |||
| 1902 | } | |||
| 1903 | ||||
| 1904 | /* we have defragmented the pdu, now free all fragments*/ | |||
| 1905 | for (fd_i=fd_head->next;fd_i;fd_i=fd_i->next) { | |||
| ||||
| 1906 | fragment_item_free_tvb(fd_i); | |||
| 1907 | } | |||
| 1908 | if (old_tvb_data) | |||
| 1909 | tvb_free(old_tvb_data); | |||
| 1910 | ||||
| 1911 | /* mark this packet as defragmented. | |||
| 1912 | * allows us to skip any trailing fragments. | |||
| 1913 | */ | |||
| 1914 | fd_head->flags |= FD_DEFRAGMENTED0x0001; | |||
| 1915 | fd_head->reassembled_in=pinfo->num; | |||
| 1916 | fd_head->reas_in_layer_num = pinfo->curr_layer_num; | |||
| 1917 | } | |||
| 1918 | ||||
| 1919 | /* | |||
| 1920 | * This function adds a new fragment to the entry for a reassembly | |||
| 1921 | * operation. | |||
| 1922 | * | |||
| 1923 | * The list of fragments for a specific datagram is kept sorted for | |||
| 1924 | * easier handling. | |||
| 1925 | * | |||
| 1926 | * Returns true if we have all the fragments, false otherwise. | |||
| 1927 | * | |||
| 1928 | * This function assumes frag_number being a block sequence number. | |||
| 1929 | * The bsn for the first block is 0. | |||
| 1930 | */ | |||
| 1931 | static bool_Bool | |||
| 1932 | fragment_add_seq_work(fragment_head *fd_head, tvbuff_t *tvb, const int offset, | |||
| 1933 | const packet_info *pinfo, const uint32_t frag_number, | |||
| 1934 | const uint32_t frag_data_len, const bool_Bool more_frags) | |||
| 1935 | { | |||
| 1936 | fragment_item *fd; | |||
| 1937 | fragment_item *fd_i; | |||
| 1938 | fragment_item *last_fd; | |||
| 1939 | uint32_t max, dfpos; | |||
| 1940 | uint32_t frag_number_work; | |||
| 1941 | ||||
| 1942 | /* Enables the use of fragment sequence numbers, which do not start with 0 */ | |||
| 1943 | frag_number_work = frag_number; | |||
| 1944 | if ( fd_head->fragment_nr_offset != 0 ) | |||
| 1945 | if ( frag_number_work >= fd_head->fragment_nr_offset ) | |||
| 1946 | frag_number_work = frag_number - fd_head->fragment_nr_offset; | |||
| 1947 | ||||
| 1948 | /* if the partial reassembly flag has been set, and we are extending | |||
| 1949 | * the pdu, un-reassemble the pdu. This means pointing old fds to malloc'ed data. | |||
| 1950 | */ | |||
| 1951 | if(fd_head->flags & FD_DEFRAGMENTED0x0001 && frag_number_work >= fd_head->datalen && | |||
| 1952 | fd_head->flags & FD_PARTIAL_REASSEMBLY0x0040){ | |||
| 1953 | uint32_t lastdfpos = 0; | |||
| 1954 | dfpos = 0; | |||
| 1955 | for(fd_i=fd_head->next; fd_i; fd_i=fd_i->next){ | |||
| 1956 | if( !fd_i->tvb_data ) { | |||
| 1957 | if( fd_i->flags & FD_OVERLAP0x0002 ) { | |||
| 1958 | /* this is a duplicate of the previous | |||
| 1959 | * fragment. */ | |||
| 1960 | fd_i->tvb_data = tvb_new_subset_remaining(fd_head->tvb_data, lastdfpos); | |||
| 1961 | } else { | |||
| 1962 | fd_i->tvb_data = tvb_new_subset_remaining(fd_head->tvb_data, dfpos); | |||
| 1963 | lastdfpos = dfpos; | |||
| 1964 | dfpos += fd_i->len; | |||
| 1965 | } | |||
| 1966 | fd_i->flags |= FD_SUBSET_TVB0x0020; | |||
| 1967 | } | |||
| 1968 | fd_i->flags &= (~FD_TOOLONGFRAGMENT0x0010) & (~FD_MULTIPLETAILS0x0008); | |||
| 1969 | } | |||
| 1970 | fd_head->flags &= ~(FD_DEFRAGMENTED0x0001|FD_PARTIAL_REASSEMBLY0x0040|FD_DATALEN_SET0x0400); | |||
| 1971 | fd_head->flags &= (~FD_TOOLONGFRAGMENT0x0010) & (~FD_MULTIPLETAILS0x0008); | |||
| 1972 | fd_head->datalen=0; | |||
| 1973 | fd_head->reassembled_in=0; | |||
| 1974 | fd_head->reas_in_layer_num = 0; | |||
| 1975 | } | |||
| 1976 | ||||
| 1977 | ||||
| 1978 | /* create new fd describing this fragment */ | |||
| 1979 | fd = new_fragment_item(pinfo->num, frag_number_work, frag_data_len); | |||
| 1980 | ||||
| 1981 | /* fd_head->frame is the maximum of the frame numbers of all the | |||
| 1982 | * fragments added to the reassembly. */ | |||
| 1983 | if (fd->frame > fd_head->frame) | |||
| 1984 | fd_head->frame = fd->frame; | |||
| 1985 | ||||
| 1986 | if (!more_frags) { | |||
| 1987 | /* | |||
| 1988 | * This is the tail fragment in the sequence. | |||
| 1989 | */ | |||
| 1990 | if (fd_head->flags&FD_DATALEN_SET0x0400) { | |||
| 1991 | /* ok we have already seen other tails for this packet | |||
| 1992 | * it might be a duplicate. | |||
| 1993 | */ | |||
| 1994 | if (fd_head->datalen != fd->offset ){ | |||
| 1995 | /* Oops, this tail indicates a different packet | |||
| 1996 | * len than the previous ones. Something's wrong. | |||
| 1997 | */ | |||
| 1998 | fd->flags |= FD_MULTIPLETAILS0x0008; | |||
| 1999 | fd_head->flags |= FD_MULTIPLETAILS0x0008; | |||
| 2000 | } | |||
| 2001 | } else { | |||
| 2002 | /* this was the first tail fragment, now we know the | |||
| 2003 | * sequence number of that fragment (which is NOT | |||
| 2004 | * the length of the packet!) | |||
| 2005 | */ | |||
| 2006 | fd_head->datalen = fd->offset; | |||
| 2007 | fd_head->flags |= FD_DATALEN_SET0x0400; | |||
| 2008 | } | |||
| 2009 | } | |||
| 2010 | ||||
| 2011 | /* If the packet is already defragmented, this MUST be an overlap. | |||
| 2012 | * The entire defragmented packet is in fd_head->data | |||
| 2013 | * Even if we have previously defragmented this packet, we still check | |||
| 2014 | * check it. Someone might play overlap and TTL games. | |||
| 2015 | */ | |||
| 2016 | if (fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 2017 | fd->flags |= FD_OVERLAP0x0002; | |||
| 2018 | fd_head->flags |= FD_OVERLAP0x0002; | |||
| 2019 | ||||
| 2020 | /* make sure it's not past the end */ | |||
| 2021 | if (fd->offset > fd_head->datalen) { | |||
| 2022 | /* new fragment comes after the end */ | |||
| 2023 | fd->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 2024 | fd_head->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 2025 | LINK_FRAG(fd_head,fd); | |||
| 2026 | return true1; | |||
| 2027 | } | |||
| 2028 | /* make sure it doesn't conflict with previous data */ | |||
| 2029 | dfpos=0; | |||
| 2030 | last_fd=NULL((void*)0); | |||
| 2031 | for (fd_i=fd_head->next;fd_i && (fd_i->offset!=fd->offset);fd_i=fd_i->next) { | |||
| 2032 | if (!last_fd || last_fd->offset!=fd_i->offset){ | |||
| 2033 | dfpos += fd_i->len; | |||
| 2034 | } | |||
| 2035 | last_fd=fd_i; | |||
| 2036 | } | |||
| 2037 | if(fd_i){ | |||
| 2038 | /* new fragment overlaps existing fragment */ | |||
| 2039 | if(fd_i->len!=fd->len){ | |||
| 2040 | /* | |||
| 2041 | * They have different lengths; this | |||
| 2042 | * is definitely a conflict. | |||
| 2043 | */ | |||
| 2044 | fd->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 2045 | fd_head->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 2046 | LINK_FRAG(fd_head,fd); | |||
| 2047 | return true1; | |||
| 2048 | } | |||
| 2049 | DISSECTOR_ASSERT(fd_head->len >= dfpos + fd->len)((void) ((fd_head->len >= dfpos + fd->len) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\"" , "epan/reassemble.c", 2049, "fd_head->len >= dfpos + fd->len" )))); | |||
| 2050 | if (tvb_memeql(fd_head->tvb_data, dfpos, | |||
| 2051 | tvb_get_ptr(tvb,offset,fd->len),fd->len) ){ | |||
| 2052 | /* | |||
| 2053 | * They have the same length, but the | |||
| 2054 | * data isn't the same. | |||
| 2055 | */ | |||
| 2056 | fd->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 2057 | fd_head->flags |= FD_OVERLAPCONFLICT0x0004; | |||
| 2058 | LINK_FRAG(fd_head,fd); | |||
| 2059 | return true1; | |||
| 2060 | } | |||
| 2061 | /* it was just an overlap, link it and return */ | |||
| 2062 | LINK_FRAG(fd_head,fd); | |||
| 2063 | return true1; | |||
| 2064 | } else { | |||
| 2065 | /* | |||
| 2066 | * New fragment doesn't overlap an existing | |||
| 2067 | * fragment - there was presumably a gap in | |||
| 2068 | * the sequence number space. | |||
| 2069 | * | |||
| 2070 | * XXX - what should we do here? Is it always | |||
| 2071 | * the case that there are no gaps, or are there | |||
| 2072 | * protcols using sequence numbers where there | |||
| 2073 | * can be gaps? | |||
| 2074 | * | |||
| 2075 | * If the former, the check below for having | |||
| 2076 | * received all the fragments should check for | |||
| 2077 | * holes in the sequence number space and for the | |||
| 2078 | * first sequence number being 0. If we do that, | |||
| 2079 | * the only way we can get here is if this fragment | |||
| 2080 | * is past the end of the sequence number space - | |||
| 2081 | * but the check for "fd->offset > fd_head->datalen" | |||
| 2082 | * would have caught that above, so it can't happen. | |||
| 2083 | * | |||
| 2084 | * If the latter, we don't have a good way of | |||
| 2085 | * knowing whether reassembly is complete if we | |||
| 2086 | * get packet out of order such that the "last" | |||
| 2087 | * fragment doesn't show up last - but, unless | |||
| 2088 | * in-order reliable delivery of fragments is | |||
| 2089 | * guaranteed, an implementation of the protocol | |||
| 2090 | * has no way of knowing whether reassembly is | |||
| 2091 | * complete, either. | |||
| 2092 | * | |||
| 2093 | * For now, we just link the fragment in and | |||
| 2094 | * return. | |||
| 2095 | */ | |||
| 2096 | LINK_FRAG(fd_head,fd); | |||
| 2097 | return true1; | |||
| 2098 | } | |||
| 2099 | } | |||
| 2100 | ||||
| 2101 | /* If we have reached this point, the packet is not defragmented yet. | |||
| 2102 | * Save all payload in a buffer until we can defragment. | |||
| 2103 | */ | |||
| 2104 | /* check len, there may be a fragment with 0 len, that is actually the tail */ | |||
| 2105 | if (fd->len) { | |||
| 2106 | if (!tvb_bytes_exist(tvb, offset, fd->len)) { | |||
| 2107 | /* abort if we didn't capture the entire fragment due | |||
| 2108 | * to a too-short snapshot length */ | |||
| 2109 | g_slice_free(fragment_item, fd)do { if (1) g_slice_free1 (sizeof (fragment_item), (fd)); else (void) ((fragment_item*) 0 == (fd)); } while (0); | |||
| 2110 | return false0; | |||
| 2111 | } | |||
| 2112 | ||||
| 2113 | fd->tvb_data = tvb_clone_offset_len(tvb, offset, fd->len); | |||
| 2114 | } | |||
| 2115 | LINK_FRAG(fd_head,fd); | |||
| 2116 | ||||
| 2117 | ||||
| 2118 | if( !(fd_head->flags & FD_DATALEN_SET0x0400) ){ | |||
| 2119 | /* if we don't know the sequence number of the last fragment, | |||
| 2120 | * there are definitely still missing packets. Cheaper than | |||
| 2121 | * the check below. | |||
| 2122 | */ | |||
| 2123 | return false0; | |||
| 2124 | } | |||
| 2125 | ||||
| 2126 | ||||
| 2127 | /* check if we have received the entire fragment | |||
| 2128 | * this is easy since the list is sorted and the head is faked. | |||
| 2129 | * common case the whole list is scanned. | |||
| 2130 | */ | |||
| 2131 | max = 0; | |||
| 2132 | for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) { | |||
| 2133 | if ( fd_i->offset==max ){ | |||
| 2134 | max++; | |||
| 2135 | } | |||
| 2136 | } | |||
| 2137 | /* max will now be datalen+1 if all fragments have been seen */ | |||
| 2138 | ||||
| 2139 | if (max <= fd_head->datalen) { | |||
| 2140 | /* we have not received all packets yet */ | |||
| 2141 | return false0; | |||
| 2142 | } | |||
| 2143 | ||||
| 2144 | ||||
| 2145 | if (max > (fd_head->datalen+1)) { | |||
| 2146 | /* oops, too long fragment detected */ | |||
| 2147 | fd->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 2148 | fd_head->flags |= FD_TOOLONGFRAGMENT0x0010; | |||
| 2149 | } | |||
| 2150 | ||||
| 2151 | ||||
| 2152 | /* we have received an entire packet, defragment it and | |||
| 2153 | * free all fragments | |||
| 2154 | */ | |||
| 2155 | fragment_defragment_and_free(fd_head, pinfo); | |||
| 2156 | ||||
| 2157 | return true1; | |||
| 2158 | } | |||
| 2159 | ||||
| 2160 | /* | |||
| 2161 | * This function adds a new fragment to the fragment hash table. | |||
| 2162 | * If this is the first fragment seen for this datagram, a new entry | |||
| 2163 | * is created in the hash table, otherwise this fragment is just added | |||
| 2164 | * to the linked list of fragments for this packet. | |||
| 2165 | * | |||
| 2166 | * Returns a pointer to the head of the fragment data list if we have all the | |||
| 2167 | * fragments, NULL otherwise. | |||
| 2168 | * | |||
| 2169 | * This function assumes frag_number being a block sequence number. | |||
| 2170 | * The bsn for the first block is 0. | |||
| 2171 | */ | |||
| 2172 | static fragment_head * | |||
| 2173 | fragment_add_seq_common(reassembly_table *table, tvbuff_t *tvb, | |||
| 2174 | const int offset, const packet_info *pinfo, | |||
| 2175 | const uint32_t id, const void *data, | |||
| 2176 | uint32_t frag_number, const uint32_t frag_data_len, | |||
| 2177 | const bool_Bool more_frags, const uint32_t flags, | |||
| 2178 | void * *orig_keyp) | |||
| 2179 | { | |||
| 2180 | fragment_head *fd_head; | |||
| 2181 | void *orig_key; | |||
| 2182 | ||||
| 2183 | fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key); | |||
| 2184 | ||||
| 2185 | /* have we already seen this frame ?*/ | |||
| 2186 | if (pinfo->fd->visited) { | |||
| 2187 | if (fd_head != NULL((void*)0) && fd_head->flags & FD_DEFRAGMENTED0x0001) { | |||
| 2188 | if (orig_keyp != NULL((void*)0)) | |||
| 2189 | *orig_keyp = orig_key; | |||
| 2190 | return fd_head; | |||
| 2191 | } else { | |||
| 2192 | return NULL((void*)0); | |||
| 2193 | } | |||
| 2194 | } | |||
| 2195 | ||||
| 2196 | if (fd_head==NULL((void*)0)){ | |||
| 2197 | /* not found, this must be the first snooped fragment for this | |||
| 2198 | * packet. Create list-head. | |||
| 2199 | */ | |||
| 2200 | fd_head = new_head(FD_BLOCKSEQUENCE0x0100); | |||
| 2201 | ||||
| 2202 | if((flags & (REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001|REASSEMBLE_FLAGS_802_11_HACK0x0002)) | |||
| 2203 | && !more_frags) { | |||
| 2204 | /* | |||
| 2205 | * This is the last fragment for this packet, and | |||
| 2206 | * is the only one we've seen. | |||
| 2207 | * | |||
| 2208 | * Either we don't have sequence numbers, in which | |||
| 2209 | * case we assume this is the first fragment for | |||
| 2210 | * this packet, or we're doing special 802.11 | |||
| 2211 | * processing, in which case we assume it's one | |||
| 2212 | * of those reassembled packets with a non-zero | |||
| 2213 | * fragment number (see packet-80211.c); just | |||
| 2214 | * return a pointer to the head of the list; | |||
| 2215 | * fragment_add_seq_check will then add it to the table | |||
| 2216 | * of reassembled packets. | |||
| 2217 | */ | |||
| 2218 | if (orig_keyp != NULL((void*)0)) | |||
| 2219 | *orig_keyp = NULL((void*)0); | |||
| 2220 | /* To save memory, we don't actually copy the | |||
| 2221 | * fragment from the tvbuff to the fragment, and in | |||
| 2222 | * process_reassembled_data just return back a subset | |||
| 2223 | * of the original tvbuff (which must be passed in). | |||
| 2224 | */ | |||
| 2225 | fd_head->len = frag_data_len; | |||
| 2226 | fd_head->reassembled_in=pinfo->num; | |||
| 2227 | fd_head->reas_in_layer_num = pinfo->curr_layer_num; | |||
| 2228 | return fd_head; | |||
| 2229 | } | |||
| 2230 | ||||
| 2231 | orig_key = insert_fd_head(table, fd_head, pinfo, id, data); | |||
| 2232 | if (orig_keyp != NULL((void*)0)) | |||
| 2233 | *orig_keyp = orig_key; | |||
| 2234 | ||||
| 2235 | /* | |||
| 2236 | * If we weren't given an initial fragment number, | |||
| 2237 | * make it 0. | |||
| 2238 | */ | |||
| 2239 | if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) | |||
| 2240 | frag_number = 0; | |||
| 2241 | } else { | |||
| 2242 | if (orig_keyp != NULL((void*)0)) | |||
| 2243 | *orig_keyp = orig_key; | |||
| 2244 | ||||
| 2245 | if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001) { | |||
| 2246 | fragment_item *fd; | |||
| 2247 | /* | |||
| 2248 | * If we weren't given an initial fragment number, | |||
| 2249 | * use the next expected fragment number as the fragment | |||
| 2250 | * number for this fragment. | |||
| 2251 | */ | |||
| 2252 | for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) { | |||
| 2253 | if (fd->next == NULL((void*)0)) | |||
| 2254 | frag_number = fd->offset + 1; | |||
| 2255 | } | |||
| 2256 | } | |||
| 2257 | } | |||
| 2258 | ||||
| 2259 | if (fragment_add_seq_work(fd_head, tvb, offset, pinfo, | |||
| 2260 | frag_number, frag_data_len, more_frags)) { | |||
| 2261 | /* | |||
| 2262 | * Reassembly is complete. | |||
| 2263 | */ | |||
| 2264 | return fd_head; | |||
| 2265 | } else { | |||
| 2266 | /* | |||
| 2267 | * Reassembly isn't complete. | |||
| 2268 | */ | |||
| 2269 | return NULL((void*)0); | |||
| 2270 | } | |||
| 2271 | } | |||
| 2272 | ||||
| 2273 | fragment_head * | |||
| 2274 | fragment_add_seq(reassembly_table *table, tvbuff_t *tvb, const int offset, | |||
| 2275 | const packet_info *pinfo, const uint32_t id, const void *data, | |||
| 2276 | const uint32_t frag_number, const uint32_t frag_data_len, | |||
| 2277 | const bool_Bool more_frags, const uint32_t flags) | |||
| 2278 | { | |||
| 2279 | return fragment_add_seq_common(table, tvb, offset, pinfo, id, data, | |||
| 2280 | frag_number, frag_data_len, | |||
| 2281 | more_frags, flags, NULL((void*)0)); | |||
| 2282 | } | |||
| 2283 | ||||
| 2284 | /* | |||
| 2285 | * This does the work for "fragment_add_seq_check()" and | |||
| 2286 | * "fragment_add_seq_next()". | |||
| 2287 | * | |||
| 2288 | * This function assumes frag_number being a block sequence number. | |||
| 2289 | * The bsn for the first block is 0. | |||
| 2290 | * | |||
| 2291 | * If REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the next expected fragment number | |||
| 2292 | * as the fragment number if there is a reassembly in progress, otherwise | |||
| 2293 | * it uses 0. | |||
| 2294 | * | |||
| 2295 | * If not REASSEMBLE_FLAGS_NO_FRAG_NUMBER, it uses the "frag_number" argument as | |||
| 2296 | * the fragment number. | |||
| 2297 | * | |||
| 2298 | * If this is the first fragment seen for this datagram, a new | |||
| 2299 | * "fragment_head" structure is allocated to refer to the reassembled | |||
| 2300 | * packet. | |||
| 2301 | * | |||
| 2302 | * This fragment is added to the linked list of fragments for this packet. | |||
| 2303 | * | |||
| 2304 | * If "more_frags" is false and REASSEMBLE_FLAGS_802_11_HACK (as the name | |||
| 2305 | * implies, a special hack for 802.11) or REASSEMBLE_FLAGS_NO_FRAG_NUMBER | |||
| 2306 | * (implying messages must be in order since there's no sequence number) are | |||
| 2307 | * set in "flags", then this (one element) list is returned. | |||
| 2308 | * | |||
| 2309 | * If, after processing this fragment, we have all the fragments, | |||
| 2310 | * "fragment_add_seq_check_work()" removes that from the fragment hash | |||
| 2311 | * table if necessary and adds it to the table of reassembled fragments, | |||
| 2312 | * and returns a pointer to the head of the fragment list. | |||
| 2313 | * | |||
| 2314 | * Otherwise, it returns NULL. | |||
| 2315 | * | |||
| 2316 | * XXX - Should we simply return NULL for zero-length fragments? | |||
| 2317 | */ | |||
| 2318 | static fragment_head * | |||
| 2319 | fragment_add_seq_check_work(reassembly_table *table, tvbuff_t *tvb, | |||
| 2320 | const int offset, const packet_info *pinfo, | |||
| 2321 | const uint32_t id, const void *data, | |||
| 2322 | const uint32_t frag_number, | |||
| 2323 | const uint32_t frag_data_len, | |||
| 2324 | const bool_Bool more_frags, const uint32_t flags) | |||
| 2325 | { | |||
| 2326 | reassembled_key reass_key; | |||
| 2327 | fragment_head *fd_head; | |||
| 2328 | void *orig_key; | |||
| 2329 | ||||
| 2330 | /* | |||
| 2331 | * Have we already seen this frame? | |||
| 2332 | * If so, look for it in the table of reassembled packets. | |||
| 2333 | */ | |||
| 2334 | if (pinfo->fd->visited) { | |||
| 2335 | reass_key.frame = pinfo->num; | |||
| 2336 | reass_key.id = id; | |||
| 2337 | return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key); | |||
| 2338 | } | |||
| 2339 | ||||
| 2340 | fd_head = fragment_add_seq_common(table, tvb, offset, pinfo, id, data, | |||
| 2341 | frag_number, frag_data_len, | |||
| 2342 | more_frags, | |||
| 2343 | flags, | |||
| 2344 | &orig_key); | |||
| 2345 | if (fd_head) { | |||
| 2346 | /* | |||
| 2347 | * Reassembly is complete. | |||
| 2348 | * | |||
| 2349 | * If this is in the table of in-progress reassemblies, | |||
| 2350 | * remove it from that table. (It could be that this | |||
| 2351 | * was the first and last fragment, so that no | |||
| 2352 | * reassembly was done.) | |||
| 2353 | */ | |||
| 2354 | if (orig_key != NULL((void*)0)) | |||
| 2355 | fragment_unhash(table, orig_key); | |||
| 2356 | ||||
| 2357 | /* | |||
| 2358 | * Add this item to the table of reassembled packets. | |||
| 2359 | */ | |||
| 2360 | fragment_reassembled(table, fd_head, pinfo, id); | |||
| 2361 | return fd_head; | |||
| 2362 | } else { | |||
| 2363 | /* | |||
| 2364 | * Reassembly isn't complete. | |||
| 2365 | */ | |||
| 2366 | return NULL((void*)0); | |||
| 2367 | } | |||
| 2368 | } | |||
| 2369 | ||||
| 2370 | fragment_head * | |||
| 2371 | fragment_add_seq_check(reassembly_table *table, tvbuff_t *tvb, const int offset, | |||
| 2372 | const packet_info *pinfo, const uint32_t id, | |||
| 2373 | const void *data, | |||
| 2374 | const uint32_t frag_number, const uint32_t frag_data_len, | |||
| 2375 | const bool_Bool more_frags) | |||
| 2376 | { | |||
| 2377 | return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data, | |||
| 2378 | frag_number, frag_data_len, | |||
| 2379 | more_frags, 0); | |||
| 2380 | } | |||
| 2381 | ||||
| 2382 | fragment_head * | |||
| 2383 | fragment_add_seq_802_11(reassembly_table *table, tvbuff_t *tvb, | |||
| 2384 | const int offset, const packet_info *pinfo, | |||
| 2385 | const uint32_t id, const void *data, | |||
| 2386 | const uint32_t frag_number, const uint32_t frag_data_len, | |||
| 2387 | const bool_Bool more_frags) | |||
| 2388 | { | |||
| 2389 | return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data, | |||
| 2390 | frag_number, frag_data_len, | |||
| 2391 | more_frags, | |||
| 2392 | REASSEMBLE_FLAGS_802_11_HACK0x0002); | |||
| 2393 | } | |||
| 2394 | ||||
| 2395 | fragment_head * | |||
| 2396 | fragment_add_seq_next(reassembly_table *table, tvbuff_t *tvb, const int offset, | |||
| 2397 | const packet_info *pinfo, const uint32_t id, | |||
| 2398 | const void *data, const uint32_t frag_data_len, | |||
| 2399 | const bool_Bool more_frags) | |||
| 2400 | { | |||
| 2401 | /* Use a dummy frag_number (0), it is ignored since | |||
| 2402 | * REASSEMBLE_FLAGS_NO_FRAG_NUMBER is set. */ | |||
| 2403 | return fragment_add_seq_check_work(table, tvb, offset, pinfo, id, data, | |||
| 2404 | 0, frag_data_len, more_frags, | |||
| 2405 | REASSEMBLE_FLAGS_NO_FRAG_NUMBER0x0001); | |||
| 2406 | } | |||
| 2407 | ||||
| 2408 | static void | |||
| 2409 | fragment_add_seq_single_move(reassembly_table *table, const packet_info *pinfo, | |||
| 2410 | const uint32_t id, const void *data, | |||
| 2411 | const uint32_t offset) | |||
| 2412 | { | |||
| 2413 | fragment_head *fh, *new_fh; | |||
| 2414 | fragment_item *fd, *prev_fd; | |||
| 2415 | tvbuff_t *old_tvb_data; | |||
| 2416 | if (offset == 0) { | |||
| 2417 | return; | |||
| 2418 | } | |||
| 2419 | fh = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 2420 | if (fh == NULL((void*)0)) { | |||
| 2421 | /* Shouldn't be called this way. | |||
| 2422 | * Probably wouldn't hurt to just create fh in this case. */ | |||
| 2423 | ws_assert_not_reached()ws_log_fatal_full("", LOG_LEVEL_ERROR, "epan/reassemble.c", 2423 , __func__, "assertion \"not reached\" failed"); | |||
| 2424 | return; | |||
| 2425 | } | |||
| 2426 | if (fh->flags & FD_DATALEN_SET0x0400 && fh->datalen <= offset) { | |||
| 2427 | /* Don't take from past the end. <= because we don't | |||
| 2428 | * want to take a First fragment from the next one | |||
| 2429 | * either */ | |||
| 2430 | return; | |||
| 2431 | } | |||
| 2432 | new_fh = lookup_fd_head(table, pinfo, id+offset, data, NULL((void*)0)); | |||
| 2433 | if (new_fh != NULL((void*)0)) { | |||
| 2434 | /* Attach to the end of the sorted list. */ | |||
| 2435 | prev_fd = NULL((void*)0); | |||
| 2436 | for(fd = fh->next; fd != NULL((void*)0); fd=fd->next) { | |||
| 2437 | prev_fd = fd; | |||
| 2438 | } | |||
| 2439 | /* Don't take a reassembly starting with a First fragment. */ | |||
| 2440 | fd = new_fh->next; | |||
| 2441 | if (fd && fd->offset != 0) { | |||
| 2442 | fragment_item *inserted = fd; | |||
| 2443 | bool_Bool multi_insert = (inserted->next != NULL((void*)0)); | |||
| 2444 | if (prev_fd) { | |||
| 2445 | prev_fd->next = fd; | |||
| 2446 | } else { | |||
| 2447 | fh->next = fd; | |||
| 2448 | } | |||
| 2449 | for (; fd; fd=fd->next) { | |||
| 2450 | fd->offset += offset; | |||
| 2451 | if (fh->frame < fd->frame) { | |||
| 2452 | fh->frame = fd->frame; | |||
| 2453 | } | |||
| 2454 | } | |||
| 2455 | update_first_gap(fh, inserted, multi_insert); | |||
| 2456 | /* If previously found a Last fragment, | |||
| 2457 | * transfer that info to the new one. */ | |||
| 2458 | if (new_fh->flags & FD_DATALEN_SET0x0400) { | |||
| 2459 | fh->flags |= FD_DATALEN_SET0x0400; | |||
| 2460 | fh->datalen = new_fh->datalen + offset; | |||
| 2461 | } | |||
| 2462 | /* Now remove and delete */ | |||
| 2463 | new_fh->next = NULL((void*)0); | |||
| 2464 | old_tvb_data = fragment_delete(table, pinfo, id+offset, data); | |||
| 2465 | if (old_tvb_data) | |||
| 2466 | tvb_free(old_tvb_data); | |||
| 2467 | } | |||
| 2468 | } | |||
| 2469 | } | |||
| 2470 | ||||
| 2471 | static fragment_head * | |||
| 2472 | fragment_add_seq_single_work(reassembly_table *table, tvbuff_t *tvb, | |||
| 2473 | const int offset, const packet_info *pinfo, | |||
| 2474 | const uint32_t id, const void* data, | |||
| 2475 | const uint32_t frag_data_len, | |||
| 2476 | const bool_Bool first, const bool_Bool last, | |||
| 2477 | const uint32_t max_frags, const uint32_t max_age, | |||
| 2478 | const uint32_t flags) | |||
| 2479 | { | |||
| 2480 | reassembled_key reass_key; | |||
| 2481 | tvbuff_t *old_tvb_data; | |||
| 2482 | void *orig_key; | |||
| 2483 | fragment_head *fh, *new_fh; | |||
| 2484 | fragment_item *fd, *prev_fd; | |||
| 2485 | uint32_t frag_number, tmp_offset; | |||
| 2486 | /* Have we already seen this frame? | |||
| 2487 | * If so, look for it in the table of reassembled packets. | |||
| 2488 | * Note here we store in the reassembly table by the single sequence | |||
| 2489 | * number rather than the sequence number of the First fragment. */ | |||
| 2490 | if (pinfo->fd->visited) { | |||
| 2491 | reass_key.frame = pinfo->num; | |||
| 2492 | reass_key.id = id; | |||
| 2493 | fh = (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key); | |||
| 2494 | return fh; | |||
| 2495 | } | |||
| 2496 | /* First let's figure out where we want to add our new fragment */ | |||
| 2497 | fh = NULL((void*)0); | |||
| 2498 | if (first) { | |||
| 2499 | frag_number = 0; | |||
| 2500 | fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0)); | |||
| 2501 | if ((flags & REASSEMBLE_FLAGS_AGING0x0001) && | |||
| 2502 | fh && ((fh->frame + max_age) < pinfo->num)) { | |||
| 2503 | old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data); | |||
| 2504 | if (old_tvb_data) | |||
| 2505 | tvb_free(old_tvb_data); | |||
| 2506 | fh = NULL((void*)0); | |||
| 2507 | } | |||
| 2508 | if (fh == NULL((void*)0)) { | |||
| 2509 | /* Not found. Create list-head. */ | |||
| 2510 | fh = new_head(FD_BLOCKSEQUENCE0x0100); | |||
| 2511 | insert_fd_head(table, fh, pinfo, id-frag_number, data); | |||
| 2512 | } | |||
| 2513 | /* As this is the first fragment, we might have added segments | |||
| 2514 | * for this reassembly to the previous one in-progress. */ | |||
| 2515 | fd = NULL((void*)0); | |||
| 2516 | for (frag_number=1; frag_number < max_frags; frag_number++) { | |||
| 2517 | new_fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0)); | |||
| 2518 | if (new_fh != NULL((void*)0)) { | |||
| 2519 | prev_fd = NULL((void*)0); | |||
| 2520 | new_fh->frame = 0; | |||
| 2521 | for (fd=new_fh->next; fd && fd->offset < frag_number; fd=fd->next) { | |||
| 2522 | prev_fd = fd; | |||
| 2523 | if (new_fh->frame < fd->frame) { | |||
| 2524 | new_fh->frame = fd->frame; | |||
| 2525 | } | |||
| 2526 | } | |||
| 2527 | if (prev_fd) { | |||
| 2528 | prev_fd->next = NULL((void*)0); | |||
| 2529 | } else { | |||
| 2530 | new_fh->next = NULL((void*)0); | |||
| 2531 | } | |||
| 2532 | fragment_items_removed(new_fh, prev_fd); | |||
| 2533 | break; | |||
| 2534 | } | |||
| 2535 | } | |||
| 2536 | if (fd != NULL((void*)0)) { | |||
| 2537 | tmp_offset = 0; | |||
| 2538 | for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) { | |||
| 2539 | prev_fd->offset -= frag_number; | |||
| 2540 | tmp_offset = prev_fd->offset; | |||
| 2541 | if (fh->frame < prev_fd->frame) { | |||
| 2542 | fh->frame = prev_fd->frame; | |||
| 2543 | } | |||
| 2544 | } | |||
| 2545 | MERGE_FRAG(fh, fd); | |||
| 2546 | if (new_fh != NULL((void*)0)) { | |||
| 2547 | /* If we've moved a Last packet, change datalen. | |||
| 2548 | * Second part of this test prob. redundant? */ | |||
| 2549 | if (new_fh->flags & FD_DATALEN_SET0x0400 && | |||
| 2550 | new_fh->datalen >= frag_number) { | |||
| 2551 | fh->flags |= FD_DATALEN_SET0x0400; | |||
| 2552 | fh->datalen = new_fh->datalen - frag_number; | |||
| 2553 | new_fh->flags &= ~FD_DATALEN_SET0x0400; | |||
| 2554 | new_fh->datalen = 0; | |||
| 2555 | } | |||
| 2556 | /* If we've moved all the fragments, | |||
| 2557 | * delete the old head */ | |||
| 2558 | if (new_fh->next == NULL((void*)0)) { | |||
| 2559 | old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data); | |||
| 2560 | if (old_tvb_data) | |||
| 2561 | tvb_free(old_tvb_data); | |||
| 2562 | } | |||
| 2563 | } else { | |||
| 2564 | /* Look forward and take off the next (this is | |||
| 2565 | * necessary in some edge cases where max_frags | |||
| 2566 | * prevented some fragments from going on the | |||
| 2567 | * previous First, but they can go on this one. */ | |||
| 2568 | fragment_add_seq_single_move(table, pinfo, id, | |||
| 2569 | data, tmp_offset); | |||
| 2570 | } | |||
| 2571 | } | |||
| 2572 | frag_number = 0; /* For the rest of the function */ | |||
| 2573 | } else { | |||
| 2574 | for (frag_number=1; frag_number < max_frags; frag_number++) { | |||
| 2575 | fh = lookup_fd_head(table, pinfo, id-frag_number, data, NULL((void*)0)); | |||
| 2576 | if ((flags & REASSEMBLE_FLAGS_AGING0x0001) && | |||
| 2577 | fh && ((fh->frame + max_age) < pinfo->num)) { | |||
| 2578 | old_tvb_data = fragment_delete(table, pinfo, id-frag_number, data); | |||
| 2579 | if (old_tvb_data) | |||
| 2580 | tvb_free(old_tvb_data); | |||
| 2581 | fh = NULL((void*)0); | |||
| 2582 | } | |||
| 2583 | if (fh != NULL((void*)0)) { | |||
| 2584 | if (fh->flags & FD_DATALEN_SET0x0400 && | |||
| 2585 | fh->datalen < frag_number) { | |||
| 2586 | /* This fragment is after the Last | |||
| 2587 | * fragment, so must go after here. */ | |||
| 2588 | fh = NULL((void*)0); | |||
| 2589 | } | |||
| 2590 | break; | |||
| 2591 | } | |||
| 2592 | } | |||
| 2593 | if (fh == NULL((void*)0)) { /* Didn't find location, use default */ | |||
| 2594 | frag_number = 1; | |||
| 2595 | /* Already looked for frag_number 1, so just create */ | |||
| 2596 | fh = new_head(FD_BLOCKSEQUENCE0x0100); | |||
| 2597 | insert_fd_head(table, fh, pinfo, id-frag_number, data); | |||
| 2598 | } | |||
| 2599 | } | |||
| 2600 | if (last) { | |||
| 2601 | /* Look for fragments past the end set by this Last fragment. */ | |||
| 2602 | prev_fd = NULL((void*)0); | |||
| 2603 | for (fd=fh->next; fd && fd->offset <= frag_number; fd=fd->next) { | |||
| 2604 | prev_fd = fd; | |||
| 2605 | } | |||
| 2606 | /* fd is now all fragments offset > frag_number (the Last). | |||
| 2607 | * It shouldn't have a fragment with offset frag_number+1, | |||
| 2608 | * as that would be a First fragment not marked as such. | |||
| 2609 | * However, this can happen if we had unreassembled fragments | |||
| 2610 | * (missing, or at the start of the capture) and we've also | |||
| 2611 | * looped around on the sequence numbers. It can also happen | |||
| 2612 | * if bit errors mess up Last or First. */ | |||
| 2613 | if (fd != NULL((void*)0)) { | |||
| 2614 | if (prev_fd) { | |||
| 2615 | prev_fd->next = NULL((void*)0); | |||
| 2616 | } else { | |||
| 2617 | fh->next = NULL((void*)0); | |||
| 2618 | } | |||
| 2619 | fragment_items_removed(fh, prev_fd); | |||
| 2620 | fh->frame = 0; | |||
| 2621 | for (prev_fd=fh->next; prev_fd; prev_fd=prev_fd->next) { | |||
| 2622 | if (fh->frame < prev_fd->frame) { | |||
| 2623 | fh->frame = prev_fd->frame; | |||
| 2624 | } | |||
| 2625 | } | |||
| 2626 | while (fd && fd->offset == frag_number+1) { | |||
| 2627 | /* Definitely have bad data here. Best to | |||
| 2628 | * delete these and leave unreassembled. */ | |||
| 2629 | fd = fragment_item_free(fd); | |||
| 2630 | } | |||
| 2631 | } | |||
| 2632 | if (fd != NULL((void*)0)) { | |||
| 2633 | /* Move these onto the next frame. */ | |||
| 2634 | new_fh = lookup_fd_head(table, pinfo, id+1, data, NULL((void*)0)); | |||
| 2635 | if (new_fh==NULL((void*)0)) { | |||
| 2636 | /* Not found. Create list-head. */ | |||
| 2637 | new_fh = new_head(FD_BLOCKSEQUENCE0x0100); | |||
| 2638 | insert_fd_head(table, new_fh, pinfo, id+1, data); | |||
| 2639 | } | |||
| 2640 | tmp_offset = 0; | |||
| 2641 | for (prev_fd = fd; prev_fd; prev_fd = prev_fd->next) { | |||
| 2642 | prev_fd->offset -= (frag_number+1); | |||
| 2643 | tmp_offset = prev_fd->offset; | |||
| 2644 | if (new_fh->frame < fd->frame) { | |||
| 2645 | new_fh->frame = fd->frame; | |||
| 2646 | } | |||
| 2647 | } | |||
| 2648 | MERGE_FRAG(new_fh, fd); | |||
| 2649 | /* If we previously found a different Last fragment, | |||
| 2650 | * transfer that information to the new reassembly. */ | |||
| 2651 | if (fh->flags & FD_DATALEN_SET0x0400 && | |||
| 2652 | fh->datalen > frag_number) { | |||
| 2653 | new_fh->flags |= FD_DATALEN_SET0x0400; | |||
| 2654 | new_fh->datalen = fh->datalen - (frag_number+1); | |||
| 2655 | fh->flags &= ~FD_DATALEN_SET0x0400; | |||
| 2656 | fh->datalen = 0; | |||
| 2657 | } else { | |||
| 2658 | /* Look forward and take off the next (this is | |||
| 2659 | * necessary in some edge cases where max_frags | |||
| 2660 | * prevented some fragments from going on the | |||
| 2661 | * previous First, but they can go on this one. */ | |||
| 2662 | fragment_add_seq_single_move(table, pinfo, id+1, | |||
| 2663 | data, tmp_offset); | |||
| 2664 | } | |||
| 2665 | } | |||
| 2666 | } else { | |||
| 2667 | fragment_add_seq_single_move(table, pinfo, id-frag_number, data, | |||
| 2668 | frag_number+1); | |||
| 2669 | } | |||
| 2670 | /* Having cleaned up everything, finally ready to add our new | |||
| 2671 | * fragment. Note that only this will ever complete a reassembly. */ | |||
| 2672 | fh = fragment_add_seq_common(table, tvb, offset, pinfo, | |||
| 2673 | id-frag_number, data, | |||
| 2674 | frag_number, frag_data_len, | |||
| 2675 | !last, 0, &orig_key); | |||
| 2676 | if (fh) { | |||
| 2677 | /* | |||
| 2678 | * Reassembly is complete. | |||
| 2679 | * | |||
| 2680 | * If this is in the table of in-progress reassemblies, | |||
| 2681 | * remove it from that table. (It could be that this | |||
| 2682 | * was the first and last fragment, so that no | |||
| 2683 | * reassembly was done.) | |||
| 2684 | */ | |||
| 2685 | if (orig_key != NULL((void*)0)) | |||
| 2686 | fragment_unhash(table, orig_key); | |||
| 2687 | ||||
| 2688 | /* | |||
| 2689 | * Add this item to the table of reassembled packets. | |||
| 2690 | */ | |||
| 2691 | fragment_reassembled_single(table, fh, pinfo, id-frag_number); | |||
| 2692 | return fh; | |||
| 2693 | } else { | |||
| 2694 | /* | |||
| 2695 | * Reassembly isn't complete. | |||
| 2696 | */ | |||
| 2697 | return NULL((void*)0); | |||
| 2698 | } | |||
| 2699 | } | |||
| 2700 | ||||
| 2701 | fragment_head * | |||
| 2702 | fragment_add_seq_single(reassembly_table *table, tvbuff_t *tvb, | |||
| 2703 | const int offset, const packet_info *pinfo, | |||
| 2704 | const uint32_t id, const void* data, | |||
| 2705 | const uint32_t frag_data_len, | |||
| 2706 | const bool_Bool first, const bool_Bool last, | |||
| 2707 | const uint32_t max_frags) | |||
| 2708 | { | |||
| 2709 | return fragment_add_seq_single_work(table, tvb, offset, pinfo, | |||
| 2710 | id, data, frag_data_len, | |||
| 2711 | first, last, max_frags, 0, 0); | |||
| 2712 | } | |||
| 2713 | ||||
| 2714 | fragment_head * | |||
| 2715 | fragment_add_seq_single_aging(reassembly_table *table, tvbuff_t *tvb, | |||
| 2716 | const int offset, const packet_info *pinfo, | |||
| 2717 | const uint32_t id, const void* data, | |||
| 2718 | const uint32_t frag_data_len, | |||
| 2719 | const bool_Bool first, const bool_Bool last, | |||
| 2720 | const uint32_t max_frags, const uint32_t max_age) | |||
| 2721 | { | |||
| 2722 | return fragment_add_seq_single_work(table, tvb, offset, pinfo, | |||
| 2723 | id, data, frag_data_len, | |||
| 2724 | first, last, max_frags, max_age, | |||
| 2725 | REASSEMBLE_FLAGS_AGING0x0001); | |||
| 2726 | } | |||
| 2727 | ||||
| 2728 | void | |||
| 2729 | fragment_start_seq_check(reassembly_table *table, const packet_info *pinfo, | |||
| 2730 | const uint32_t id, const void *data, | |||
| 2731 | const uint32_t tot_len) | |||
| 2732 | { | |||
| 2733 | fragment_head *fd_head; | |||
| 2734 | ||||
| 2735 | /* Have we already seen this frame ?*/ | |||
| 2736 | if (pinfo->fd->visited) { | |||
| 2737 | return; | |||
| 2738 | } | |||
| 2739 | ||||
| 2740 | /* Check if fragment data exists */ | |||
| 2741 | fd_head = lookup_fd_head(table, pinfo, id, data, NULL((void*)0)); | |||
| 2742 | ||||
| 2743 | if (fd_head == NULL((void*)0)) { | |||
| 2744 | /* Create list-head. */ | |||
| 2745 | fd_head = new_head(FD_BLOCKSEQUENCE0x0100|FD_DATALEN_SET0x0400); | |||
| 2746 | fd_head->datalen = tot_len; | |||
| 2747 | ||||
| 2748 | insert_fd_head(table, fd_head, pinfo, id, data); | |||
| 2749 | } | |||
| 2750 | } | |||
| 2751 | ||||
| 2752 | fragment_head * | |||
| 2753 | fragment_end_seq_next(reassembly_table *table, const packet_info *pinfo, | |||
| 2754 | const uint32_t id, const void *data) | |||
| 2755 | { | |||
| 2756 | reassembled_key reass_key; | |||
| 2757 | reassembled_key *new_key; | |||
| 2758 | fragment_head *fd_head; | |||
| 2759 | fragment_item *fd; | |||
| 2760 | void *orig_key; | |||
| 2761 | uint32_t max_offset = 0; | |||
| 2762 | ||||
| 2763 | /* | |||
| 2764 | * Have we already seen this frame? | |||
| 2765 | * If so, look for it in the table of reassembled packets. | |||
| 2766 | */ | |||
| 2767 | if (pinfo->fd->visited) { | |||
| ||||
| 2768 | reass_key.frame = pinfo->num; | |||
| 2769 | reass_key.id = id; | |||
| 2770 | return (fragment_head *)g_hash_table_lookup(table->reassembled_table, &reass_key); | |||
| 2771 | } | |||
| 2772 | ||||
| 2773 | fd_head = lookup_fd_head(table, pinfo, id, data, &orig_key); | |||
| 2774 | ||||
| 2775 | if (fd_head) { | |||
| 2776 | for (fd = fd_head->next; fd; fd = fd->next) { | |||
| 2777 | if (fd->offset > max_offset) { | |||
| 2778 | max_offset = fd->offset; | |||
| 2779 | } | |||
| 2780 | } | |||
| 2781 | fd_head->datalen = max_offset; | |||
| 2782 | fd_head->flags |= FD_DATALEN_SET0x0400; | |||
| 2783 | ||||
| 2784 | fragment_defragment_and_free (fd_head, pinfo); | |||
| 2785 | ||||
| 2786 | /* | |||
| 2787 | * Remove this from the table of in-progress reassemblies, | |||
| 2788 | * and free up any memory used for it in that table. | |||
| 2789 | */ | |||
| 2790 | fragment_unhash(table, orig_key); | |||
| 2791 | ||||
| 2792 | /* | |||
| 2793 | * Add this item to the table of reassembled packets. | |||
| 2794 | */ | |||
| 2795 | fragment_reassembled(table, fd_head, pinfo, id); | |||
| 2796 | if (fd_head->next != NULL((void*)0)) { | |||
| 2797 | new_key = g_slice_new(reassembled_key)((reassembled_key*) g_slice_alloc (sizeof (reassembled_key))); | |||
| 2798 | new_key->frame = pinfo->num; | |||
| 2799 | new_key->id = id; | |||
| 2800 | reassembled_table_insert(table->reassembled_table, new_key, fd_head); | |||
| 2801 | } | |||
| 2802 | ||||
| 2803 | return fd_head; | |||
| 2804 | } else { | |||
| 2805 | /* | |||
| 2806 | * Fragment data not found. | |||
| 2807 | */ | |||
| 2808 | return NULL((void*)0); | |||
| 2809 | } | |||
| 2810 | } | |||
| 2811 | ||||
| 2812 | /* | |||
| 2813 | * Process reassembled data; if we're on the frame in which the data | |||
| 2814 | * was reassembled, put the fragment information into the protocol | |||
| 2815 | * tree, and construct a tvbuff with the reassembled data, otherwise | |||
| 2816 | * just put a "reassembled in" item into the protocol tree. | |||
| 2817 | * offset from start of tvb, result up to end of tvb | |||
| 2818 | */ | |||
| 2819 | tvbuff_t * | |||
| 2820 | process_reassembled_data(tvbuff_t *tvb, const int offset, packet_info *pinfo, | |||
| 2821 | const char *name, fragment_head *fd_head, const fragment_items *fit, | |||
| 2822 | bool_Bool *update_col_infop, proto_tree *tree) | |||
| 2823 | { | |||
| 2824 | tvbuff_t *next_tvb; | |||
| 2825 | bool_Bool update_col_info; | |||
| 2826 | proto_item *frag_tree_item; | |||
| 2827 | ||||
| 2828 | if (fd_head != NULL((void*)0) && pinfo->num == fd_head->reassembled_in && pinfo->curr_layer_num == fd_head->reas_in_layer_num) { | |||
| 2829 | /* | |||
| 2830 | * OK, we've reassembled this. | |||
| 2831 | * Is this something that's been reassembled from more | |||
| 2832 | * than one fragment? | |||
| 2833 | */ | |||
| 2834 | if (fd_head->next != NULL((void*)0)) { | |||
| 2835 | /* | |||
| 2836 | * Yes. | |||
| 2837 | * Allocate a new tvbuff, referring to the | |||
| 2838 | * reassembled payload, and set | |||
| 2839 | * the tvbuff to the list of tvbuffs to which | |||
| 2840 | * the tvbuff we were handed refers, so it'll get | |||
| 2841 | * cleaned up when that tvbuff is cleaned up. | |||
| 2842 | */ | |||
| 2843 | next_tvb = tvb_new_chain(tvb, fd_head->tvb_data); | |||
| 2844 | ||||
| 2845 | /* Add the defragmented data to the data source list. */ | |||
| 2846 | add_new_data_source(pinfo, next_tvb, name); | |||
| 2847 | ||||
| 2848 | /* show all fragments */ | |||
| 2849 | if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) { | |||
| 2850 | update_col_info = !show_fragment_seq_tree( | |||
| 2851 | fd_head, fit, tree, pinfo, next_tvb, &frag_tree_item); | |||
| 2852 | } else { | |||
| 2853 | update_col_info = !show_fragment_tree(fd_head, | |||
| 2854 | fit, tree, pinfo, next_tvb, &frag_tree_item); | |||
| 2855 | } | |||
| 2856 | } else { | |||
| 2857 | /* | |||
| 2858 | * No. | |||
| 2859 | * Return a tvbuff with the payload, a subset of the | |||
| 2860 | * tvbuff passed in. (The dissector SHOULD pass in | |||
| 2861 | * the correct tvbuff and offset.) | |||
| 2862 | */ | |||
| 2863 | int len; | |||
| 2864 | /* For FD_BLOCKSEQUENCE, len is the length in bytes, | |||
| 2865 | * datalen is the number of fragments. | |||
| 2866 | */ | |||
| 2867 | if (fd_head->flags & FD_BLOCKSEQUENCE0x0100) { | |||
| 2868 | len = fd_head->len; | |||
| 2869 | } else { | |||
| 2870 | // XXX Do the non-seq functions have this optimization? | |||
| 2871 | len = fd_head->datalen; | |||
| 2872 | } | |||
| 2873 | next_tvb = tvb_new_subset_length(tvb, offset, len); | |||
| 2874 | pinfo->fragmented = false0; /* one-fragment packet */ | |||
| 2875 | update_col_info = true1; | |||
| 2876 | } | |||
| 2877 | if (update_col_infop != NULL((void*)0)) | |||
| 2878 | *update_col_infop = update_col_info; | |||
| 2879 | } else { | |||
| 2880 | /* | |||
| 2881 | * We don't have the complete reassembled payload, or this | |||
| 2882 | * isn't the final frame of that payload. | |||
| 2883 | */ | |||
| 2884 | next_tvb = NULL((void*)0); | |||
| 2885 | ||||
| 2886 | /* | |||
| 2887 | * If we know what frame this was reassembled in, | |||
| 2888 | * and if there's a field to use for the number of | |||
| 2889 | * the frame in which the packet was reassembled, | |||
| 2890 | * add it to the protocol tree. | |||
| 2891 | */ | |||
| 2892 | if (fd_head != NULL((void*)0) && fit->hf_reassembled_in != NULL((void*)0)) { | |||
| 2893 | proto_item *fei = proto_tree_add_uint(tree, | |||
| 2894 | *(fit->hf_reassembled_in), tvb, | |||
| 2895 | 0, 0, fd_head->reassembled_in); | |||
| 2896 | proto_item_set_generated(fei); | |||
| 2897 | } | |||
| 2898 | } | |||
| 2899 | return next_tvb; | |||
| 2900 | } | |||
| 2901 | ||||
| 2902 | /* | |||
| 2903 | * Show a single fragment in a fragment subtree, and put information about | |||
| 2904 | * it in the top-level item for that subtree. | |||
| 2905 | */ | |||
| 2906 | static void | |||
| 2907 | show_fragment(fragment_item *fd, const int offset, const fragment_items *fit, | |||
| 2908 | proto_tree *ft, proto_item *fi, const bool_Bool first_frag, | |||
| 2909 | const uint32_t count, tvbuff_t *tvb, packet_info *pinfo) | |||
| 2910 | { | |||
| 2911 | proto_item *fei=NULL((void*)0); | |||
| 2912 | int hf; | |||
| 2913 | ||||
| 2914 | if (first_frag) { | |||
| 2915 | char *name; | |||
| 2916 | if (count == 1) { | |||
| 2917 | name = g_strdup(proto_registrar_get_name(*(fit->hf_fragment)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragment ))); | |||
| 2918 | } else { | |||
| 2919 | name = g_strdup(proto_registrar_get_name(*(fit->hf_fragments)))g_strdup_inline (proto_registrar_get_name(*(fit->hf_fragments ))); | |||
| 2920 | } | |||
| 2921 | proto_item_set_text(fi, "%u %s (%u byte%s): ", count, name, tvb_captured_length(tvb), | |||
| 2922 | plurality(tvb_captured_length(tvb), "", "s")((tvb_captured_length(tvb)) == 1 ? ("") : ("s"))); | |||
| 2923 | g_free(name); | |||
| 2924 | } else { | |||
| 2925 | proto_item_append_text(fi, ", "); | |||
| 2926 | } | |||
| 2927 | proto_item_append_text(fi, "#%u(%u)", fd->frame, fd->len); | |||
| 2928 | ||||
| 2929 | if (fd->flags & (FD_OVERLAPCONFLICT0x0004 | |||
| 2930 | |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) { | |||
| 2931 | hf = *(fit->hf_fragment_error); | |||
| 2932 | } else { | |||
| 2933 | hf = *(fit->hf_fragment); | |||
| 2934 | } | |||
| 2935 | if (fd->len == 0) { | |||
| 2936 | fei = proto_tree_add_uint_format(ft, hf, | |||
| 2937 | tvb, offset, fd->len, | |||
| 2938 | fd->frame, | |||
| 2939 | "Frame: %u (no data)", | |||
| 2940 | fd->frame); | |||
| 2941 | } else { | |||
| 2942 | fei = proto_tree_add_uint_format(ft, hf, | |||
| 2943 | tvb, offset, fd->len, | |||
| 2944 | fd->frame, | |||
| 2945 | "Frame: %u, payload: %u-%u (%u byte%s)", | |||
| 2946 | fd->frame, | |||
| 2947 | offset, | |||
| 2948 | offset+fd->len-1, | |||
| 2949 | fd->len, | |||
| 2950 | plurality(fd->len, "", "s")((fd->len) == 1 ? ("") : ("s"))); | |||
| 2951 | } | |||
| 2952 | proto_item_set_generated(fei); | |||
| 2953 | mark_frame_as_depended_upon(pinfo->fd, fd->frame); | |||
| 2954 | if (fd->flags & (FD_OVERLAP0x0002|FD_OVERLAPCONFLICT0x0004 | |||
| 2955 | |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) { | |||
| 2956 | /* this fragment has some flags set, create a subtree | |||
| 2957 | * for it and display the flags. | |||
| 2958 | */ | |||
| 2959 | proto_tree *fet=NULL((void*)0); | |||
| 2960 | ||||
| 2961 | fet = proto_item_add_subtree(fei, *(fit->ett_fragment)); | |||
| 2962 | if (fd->flags&FD_OVERLAP0x0002) { | |||
| 2963 | fei=proto_tree_add_boolean(fet, | |||
| 2964 | *(fit->hf_fragment_overlap), | |||
| 2965 | tvb, 0, 0, | |||
| 2966 | true1); | |||
| 2967 | proto_item_set_generated(fei); | |||
| 2968 | } | |||
| 2969 | if (fd->flags&FD_OVERLAPCONFLICT0x0004) { | |||
| 2970 | fei=proto_tree_add_boolean(fet, | |||
| 2971 | *(fit->hf_fragment_overlap_conflict), | |||
| 2972 | tvb, 0, 0, | |||
| 2973 | true1); | |||
| 2974 | proto_item_set_generated(fei); | |||
| 2975 | } | |||
| 2976 | if (fd->flags&FD_MULTIPLETAILS0x0008) { | |||
| 2977 | fei=proto_tree_add_boolean(fet, | |||
| 2978 | *(fit->hf_fragment_multiple_tails), | |||
| 2979 | tvb, 0, 0, | |||
| 2980 | true1); | |||
| 2981 | proto_item_set_generated(fei); | |||
| 2982 | } | |||
| 2983 | if (fd->flags&FD_TOOLONGFRAGMENT0x0010) { | |||
| 2984 | fei=proto_tree_add_boolean(fet, | |||
| 2985 | *(fit->hf_fragment_too_long_fragment), | |||
| 2986 | tvb, 0, 0, | |||
| 2987 | true1); | |||
| 2988 | proto_item_set_generated(fei); | |||
| 2989 | } | |||
| 2990 | } | |||
| 2991 | } | |||
| 2992 | ||||
| 2993 | static bool_Bool | |||
| 2994 | show_fragment_errs_in_col(fragment_head *fd_head, const fragment_items *fit, | |||
| 2995 | packet_info *pinfo) | |||
| 2996 | { | |||
| 2997 | if (fd_head->flags & (FD_OVERLAPCONFLICT0x0004 | |||
| 2998 | |FD_MULTIPLETAILS0x0008|FD_TOOLONGFRAGMENT0x0010) ) { | |||
| 2999 | col_add_fstr(pinfo->cinfo, COL_INFO, "[Illegal %s]", fit->tag); | |||
| 3000 | return true1; | |||
| 3001 | } | |||
| 3002 | ||||
| 3003 | return false0; | |||
| 3004 | } | |||
| 3005 | ||||
| 3006 | /* This function will build the fragment subtree; it's for fragments | |||
| 3007 | reassembled with "fragment_add()". | |||
| 3008 | ||||
| 3009 | It will return true if there were fragmentation errors | |||
| 3010 | or false if fragmentation was ok. | |||
| 3011 | */ | |||
| 3012 | bool_Bool | |||
| 3013 | show_fragment_tree(fragment_head *fd_head, const fragment_items *fit, | |||
| 3014 | proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi) | |||
| 3015 | { | |||
| 3016 | fragment_item *fd; | |||
| 3017 | proto_tree *ft; | |||
| 3018 | bool_Bool first_frag; | |||
| 3019 | uint32_t count = 0; | |||
| 3020 | /* It's not fragmented. */ | |||
| 3021 | pinfo->fragmented = false0; | |||
| 3022 | ||||
| 3023 | *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000); | |||
| 3024 | proto_item_set_generated(*fi); | |||
| 3025 | ||||
| 3026 | ft = proto_item_add_subtree(*fi, *(fit->ett_fragments)); | |||
| 3027 | first_frag = true1; | |||
| 3028 | for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) { | |||
| 3029 | count++; | |||
| 3030 | } | |||
| 3031 | for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next) { | |||
| 3032 | show_fragment(fd, fd->offset, fit, ft, *fi, first_frag, count, tvb, pinfo); | |||
| 3033 | first_frag = false0; | |||
| 3034 | } | |||
| 3035 | ||||
| 3036 | if (fit->hf_fragment_count) { | |||
| 3037 | proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count), | |||
| 3038 | tvb, 0, 0, count); | |||
| 3039 | proto_item_set_generated(fli); | |||
| 3040 | } | |||
| 3041 | ||||
| 3042 | if (fit->hf_reassembled_length) { | |||
| 3043 | proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length), | |||
| 3044 | tvb, 0, 0, tvb_captured_length (tvb)); | |||
| 3045 | proto_item_set_generated(fli); | |||
| 3046 | } | |||
| 3047 | ||||
| 3048 | if (fit->hf_reassembled_data) { | |||
| 3049 | proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data), | |||
| 3050 | tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000); | |||
| 3051 | proto_item_set_generated(fli); | |||
| 3052 | } | |||
| 3053 | ||||
| 3054 | return show_fragment_errs_in_col(fd_head, fit, pinfo); | |||
| 3055 | } | |||
| 3056 | ||||
| 3057 | /* This function will build the fragment subtree; it's for fragments | |||
| 3058 | reassembled with "fragment_add_seq()" or "fragment_add_seq_check()". | |||
| 3059 | ||||
| 3060 | It will return true if there were fragmentation errors | |||
| 3061 | or false if fragmentation was ok. | |||
| 3062 | */ | |||
| 3063 | bool_Bool | |||
| 3064 | show_fragment_seq_tree(fragment_head *fd_head, const fragment_items *fit, | |||
| 3065 | proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi) | |||
| 3066 | { | |||
| 3067 | uint32_t offset, next_offset, count = 0; | |||
| 3068 | fragment_item *fd, *last_fd; | |||
| 3069 | proto_tree *ft; | |||
| 3070 | bool_Bool first_frag; | |||
| 3071 | ||||
| 3072 | /* It's not fragmented. */ | |||
| 3073 | pinfo->fragmented = false0; | |||
| 3074 | ||||
| 3075 | *fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA0x00000000); | |||
| 3076 | proto_item_set_generated(*fi); | |||
| 3077 | ||||
| 3078 | ft = proto_item_add_subtree(*fi, *(fit->ett_fragments)); | |||
| 3079 | offset = 0; | |||
| 3080 | next_offset = 0; | |||
| 3081 | last_fd = NULL((void*)0); | |||
| 3082 | first_frag = true1; | |||
| 3083 | for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){ | |||
| 3084 | count++; | |||
| 3085 | } | |||
| 3086 | for (fd = fd_head->next; fd != NULL((void*)0); fd = fd->next){ | |||
| 3087 | if (last_fd == NULL((void*)0) || last_fd->offset != fd->offset) { | |||
| 3088 | offset = next_offset; | |||
| 3089 | next_offset += fd->len; | |||
| 3090 | } | |||
| 3091 | last_fd = fd; | |||
| 3092 | show_fragment(fd, offset, fit, ft, *fi, first_frag, count, tvb, pinfo); | |||
| 3093 | first_frag = false0; | |||
| 3094 | } | |||
| 3095 | ||||
| 3096 | if (fit->hf_fragment_count) { | |||
| 3097 | proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count), | |||
| 3098 | tvb, 0, 0, count); | |||
| 3099 | proto_item_set_generated(fli); | |||
| 3100 | } | |||
| 3101 | ||||
| 3102 | if (fit->hf_reassembled_length) { | |||
| 3103 | proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length), | |||
| 3104 | tvb, 0, 0, tvb_captured_length (tvb)); | |||
| 3105 | proto_item_set_generated(fli); | |||
| 3106 | } | |||
| 3107 | ||||
| 3108 | if (fit->hf_reassembled_data) { | |||
| 3109 | proto_item *fli = proto_tree_add_item(ft, *(fit->hf_reassembled_data), | |||
| 3110 | tvb, 0, tvb_captured_length(tvb), ENC_NA0x00000000); | |||
| 3111 | proto_item_set_generated(fli); | |||
| 3112 | } | |||
| 3113 | ||||
| 3114 | return show_fragment_errs_in_col(fd_head, fit, pinfo); | |||
| 3115 | } | |||
| 3116 | ||||
| 3117 | static void | |||
| 3118 | reassembly_table_init_reg_table(void *p, void *user_data _U___attribute__((unused))) | |||
| 3119 | { | |||
| 3120 | register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p; | |||
| 3121 | reassembly_table_init(reg_table->table, reg_table->funcs); | |||
| 3122 | } | |||
| 3123 | ||||
| 3124 | static void | |||
| 3125 | reassembly_table_init_reg_tables(void) | |||
| 3126 | { | |||
| 3127 | g_list_foreach(reassembly_table_list, reassembly_table_init_reg_table, NULL((void*)0)); | |||
| 3128 | } | |||
| 3129 | ||||
| 3130 | static void | |||
| 3131 | reassembly_table_cleanup_reg_table(void *p, void *user_data _U___attribute__((unused))) | |||
| 3132 | { | |||
| 3133 | register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p; | |||
| 3134 | reassembly_table_destroy(reg_table->table); | |||
| 3135 | } | |||
| 3136 | ||||
| 3137 | static void | |||
| 3138 | reassembly_table_cleanup_reg_tables(void) | |||
| 3139 | { | |||
| 3140 | g_list_foreach(reassembly_table_list, reassembly_table_cleanup_reg_table, NULL((void*)0)); | |||
| 3141 | } | |||
| 3142 | ||||
| 3143 | void reassembly_tables_init(void) | |||
| 3144 | { | |||
| 3145 | register_init_routine(&reassembly_table_init_reg_tables); | |||
| 3146 | register_cleanup_routine(&reassembly_table_cleanup_reg_tables); | |||
| 3147 | } | |||
| 3148 | ||||
| 3149 | static void | |||
| 3150 | reassembly_table_free(void *p, void *user_data _U___attribute__((unused))) | |||
| 3151 | { | |||
| 3152 | register_reassembly_table_t* reg_table = (register_reassembly_table_t*)p; | |||
| 3153 | reassembly_table_destroy(reg_table->table); | |||
| 3154 | g_free(reg_table); | |||
| 3155 | } | |||
| 3156 | ||||
| 3157 | void | |||
| 3158 | reassembly_table_cleanup(void) | |||
| 3159 | { | |||
| 3160 | g_list_foreach(reassembly_table_list, reassembly_table_free, NULL((void*)0)); | |||
| 3161 | g_list_free(reassembly_table_list); | |||
| 3162 | } | |||
| 3163 | ||||
| 3164 | /* One instance of this structure is created for each pdu that spans across | |||
| 3165 | * multiple segments. (MSP) */ | |||
| 3166 | typedef struct _multisegment_pdu_t { | |||
| 3167 | uint64_t first_frame; | |||
| 3168 | uint64_t last_frame; | |||
| 3169 | unsigned start_offset_at_first_frame; | |||
| 3170 | unsigned end_offset_at_last_frame; | |||
| 3171 | int length; /* length of this MSP */ | |||
| 3172 | uint32_t streaming_reassembly_id; | |||
| 3173 | /* pointer to previous multisegment_pdu */ | |||
| 3174 | struct _multisegment_pdu_t* prev_msp; | |||
| 3175 | } multisegment_pdu_t; | |||
| 3176 | ||||
| 3177 | /* struct for keeping the reassembly information of each stream */ | |||
| 3178 | struct streaming_reassembly_info_t { | |||
| 3179 | /* This map is keyed by frame num and keeps track of all MSPs for this | |||
| 3180 | * stream. Different frames will point to the same MSP if they contain | |||
| 3181 | * part data of this MSP. If a frame contains data that | |||
| 3182 | * belongs to two MSPs, it will point to the second MSP. */ | |||
| 3183 | wmem_map_t* multisegment_pdus; | |||
| 3184 | /* This map is keyed by frame num and keeps track of the frag_offset | |||
| 3185 | * of the first byte of frames for fragment_add() after first scan. */ | |||
| 3186 | wmem_map_t* frame_num_frag_offset_map; | |||
| 3187 | /* how many bytes the current uncompleted MSP still needs. (only valid for first scan) */ | |||
| 3188 | int prev_deseg_len; | |||
| 3189 | /* the current uncompleted MSP (only valid for first scan) */ | |||
| 3190 | multisegment_pdu_t* last_msp; | |||
| 3191 | }; | |||
| 3192 | ||||
| 3193 | static uint32_t | |||
| 3194 | create_streaming_reassembly_id(void) | |||
| 3195 | { | |||
| 3196 | static uint32_t global_streaming_reassembly_id = 0; | |||
| 3197 | return ++global_streaming_reassembly_id; | |||
| 3198 | } | |||
| 3199 | ||||
| 3200 | streaming_reassembly_info_t* | |||
| 3201 | streaming_reassembly_info_new(void) | |||
| 3202 | { | |||
| 3203 | return wmem_new0(wmem_file_scope(), streaming_reassembly_info_t)((streaming_reassembly_info_t*)wmem_alloc0((wmem_file_scope() ), sizeof(streaming_reassembly_info_t))); | |||
| 3204 | } | |||
| 3205 | ||||
| 3206 | /* Following is an example of ProtoA and ProtoB protocols from the declaration of this function in 'reassemble.h': | |||
| 3207 | * | |||
| 3208 | * +------------------ A Multisegment PDU of ProtoB ----------------------+ | |||
| 3209 | * | | | |||
| 3210 | * +--- ProtoA payload1 ---+ +- payload2 -+ +- Payload3 -+ +- Payload4 -+ +- ProtoA payload5 -+ | |||
| 3211 | * | EoMSP | OmNFP | BoMSP | | MoMSP | | MoMSP | | MoMSP | | EoMSP | BoMSP | | |||
| 3212 | * +-------+-------+-------+ +------------+ +------------+ +------------+ +---------+---------+ | |||
| 3213 | * | | | |||
| 3214 | * +----------------------------------------------------------------------+ | |||
| 3215 | * | |||
| 3216 | * For a ProtoA payload composed of EoMSP + OmNFP + BoMSP will call fragment_add() twice on EoMSP and BoMSP; and call | |||
| 3217 | * process_reassembled_data() once for generating tvb of a MSP to which EoMSP belongs; and call subdissector twice on | |||
| 3218 | * reassembled MSP of EoMSP and OmNFP + BoMSP. After that finds BoMSP is a beginning of a MSP at first scan. | |||
| 3219 | * | |||
| 3220 | * The rules are: | |||
| 3221 | * | |||
| 3222 | * - If a ProtoA payload contains EoMSP, we will need call fragment_add(), process_reassembled_data() and subdissector | |||
| 3223 | * once on it to end a MSP. (May run twice or more times at first scan, because subdissector may only return the | |||
| 3224 | * head length of message by pinfo->desegment_len. We need run second time for subdissector to determine the length | |||
| 3225 | * of entire message). | |||
| 3226 | * | |||
| 3227 | * - If a ProtoA payload contains OmNFP, we will need only call subdissector once on it. The subdissector need dissect | |||
| 3228 | * all non-fragment PDUs in it. (no desegment_len should output) | |||
| 3229 | * | |||
| 3230 | * - If a ProtoA payload contains BoMSP, we will need call subdissector once on BoMSP or OmNFP+BoMSP (because unknown | |||
| 3231 | * during first scan). The subdissector will output desegment_len (!= 0). Then we will call fragment_add() | |||
| 3232 | * with a new reassembly id on BoMSP for starting a new MSP. | |||
| 3233 | * | |||
| 3234 | * - If a ProtoA payload only contains MoMSP (entire payload is part of a MSP), we will only call fragment_add() once | |||
| 3235 | * or twice (at first scan) on it. The subdissector will not be called. | |||
| 3236 | * | |||
| 3237 | * In this implementation, only multisegment PDUs are recorded in multisegment_pdus map keyed by the numbers (uint64_t) | |||
| 3238 | * of frames belongs to MSPs. Each MSP in the map has a pointer referred to previous MSP, because we may need | |||
| 3239 | * two MSPs to dissect a ProtoA payload that contains EoMSP + BoMSP at the same time. The multisegment_pdus map is built | |||
| 3240 | * during first scan (pinfo->visited == false) with help of prev_deseg_len and last_msp fields of streaming_reassembly_info_t | |||
| 3241 | * for each direction of a ProtoA STREAM. The prev_deseg_len record how many bytes of subsequent ProtoA payloads belong to | |||
| 3242 | * previous PDU during first scan. The last_msp member of streaming_reassembly_info_t is always point to last MSP which | |||
| 3243 | * is created during scan previous or early ProtoA payloads. Since subdissector might return only the head length of entire | |||
| 3244 | * message (by pinfo->desegment_len) when there is not enough data to determine the message length, we need to reopen | |||
| 3245 | * reassembly fragments for adding more bytes during scanning the next ProtoA payload. We have to use fragment_add() | |||
| 3246 | * instead of fragment_add_check() or fragment_add_seq_next(). | |||
| 3247 | * | |||
| 3248 | * Read more: please refer to comments of the declaration of this function in 'reassemble.h'. | |||
| 3249 | */ | |||
| 3250 | int | |||
| 3251 | reassemble_streaming_data_and_call_subdissector( | |||
| 3252 | tvbuff_t* tvb, packet_info* pinfo, unsigned offset, int length, | |||
| 3253 | proto_tree* segment_tree, proto_tree* reassembled_tree, reassembly_table streaming_reassembly_table, | |||
| 3254 | streaming_reassembly_info_t* reassembly_info, uint64_t cur_frame_num, | |||
| 3255 | dissector_handle_t subdissector_handle, proto_tree* subdissector_tree, void* subdissector_data, | |||
| 3256 | const char* label, const fragment_items* frag_hf_items, int hf_segment_data | |||
| 3257 | ) | |||
| 3258 | { | |||
| 3259 | int orig_length = length; | |||
| 3260 | int datalen = 0; | |||
| 3261 | int bytes_belong_to_prev_msp = 0; /* bytes belong to previous MSP */ | |||
| 3262 | uint32_t reassembly_id = 0, frag_offset = 0; | |||
| 3263 | fragment_head* head = NULL((void*)0); | |||
| 3264 | bool_Bool need_more = false0; | |||
| 3265 | bool_Bool found_BoMSP = false0; | |||
| 3266 | multisegment_pdu_t* cur_msp = NULL((void*)0), * prev_msp = NULL((void*)0); | |||
| 3267 | uint16_t save_can_desegment; | |||
| 3268 | int save_desegment_offset; | |||
| 3269 | uint32_t save_desegment_len; | |||
| 3270 | uint64_t* frame_ptr; | |||
| 3271 | ||||
| 3272 | save_can_desegment = pinfo->can_desegment; | |||
| 3273 | save_desegment_offset = pinfo->desegment_offset; | |||
| 3274 | save_desegment_len = pinfo->desegment_len; | |||
| 3275 | ||||
| 3276 | /* calculate how many bytes of this payload belongs to previous MSP (EoMSP) */ | |||
| 3277 | if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) { | |||
| 3278 | /* this is first scan */ | |||
| 3279 | if (reassembly_info->prev_deseg_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) { | |||
| 3280 | /* assuming the entire tvb belongs to the previous MSP */ | |||
| 3281 | bytes_belong_to_prev_msp = length; | |||
| 3282 | reassembly_info->prev_deseg_len = length; | |||
| 3283 | } else if (reassembly_info->prev_deseg_len > 0) { | |||
| 3284 | /* part or all of current payload belong to previous MSP */ | |||
| 3285 | bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info ->prev_deseg_len) : (length)); | |||
| 3286 | reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp; | |||
| 3287 | need_more = (reassembly_info->prev_deseg_len > 0); | |||
| 3288 | } /* else { beginning of a new PDU (might be a NFP or MSP) } */ | |||
| 3289 | ||||
| 3290 | if (bytes_belong_to_prev_msp > 0) { | |||
| 3291 | DISSECTOR_ASSERT(reassembly_info->last_msp != NULL)((void) ((reassembly_info->last_msp != ((void*)0)) ? (void )0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\"" , "epan/reassemble.c", 3291, "reassembly_info->last_msp != ((void*)0)" )))); | |||
| 3292 | reassembly_id = reassembly_info->last_msp->streaming_reassembly_id; | |||
| 3293 | frag_offset = reassembly_info->last_msp->length; | |||
| 3294 | if (reassembly_info->frame_num_frag_offset_map == NULL((void*)0)) { | |||
| 3295 | reassembly_info->frame_num_frag_offset_map = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal); | |||
| 3296 | } | |||
| 3297 | frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t)); | |||
| 3298 | wmem_map_insert(reassembly_info->frame_num_frag_offset_map, frame_ptr, GUINT_TO_POINTER(frag_offset)((gpointer) (gulong) (frag_offset))); | |||
| 3299 | /* This payload contains the data of previous msp, so we point to it. That may be overridden late. */ | |||
| 3300 | wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, reassembly_info->last_msp); | |||
| 3301 | } | |||
| 3302 | } else { | |||
| 3303 | /* not first scan, use information of multisegment_pdus built during first scan */ | |||
| 3304 | if (reassembly_info->multisegment_pdus) { | |||
| 3305 | cur_msp = (multisegment_pdu_t*)wmem_map_lookup(reassembly_info->multisegment_pdus, &cur_frame_num); | |||
| 3306 | } | |||
| 3307 | if (cur_msp) { | |||
| 3308 | if (cur_msp->first_frame == cur_frame_num) { | |||
| 3309 | /* Current payload contains a beginning of a MSP. (BoMSP) | |||
| 3310 | * The cur_msp contains information about the beginning MSP. | |||
| 3311 | * If prev_msp is not null, that means this payload also contains | |||
| 3312 | * the last part of previous MSP. (EoMSP) */ | |||
| 3313 | prev_msp = cur_msp->prev_msp; | |||
| 3314 | } else { | |||
| 3315 | /* Current payload is not a first frame of a MSP (not include BoMSP). */ | |||
| 3316 | prev_msp = cur_msp; | |||
| 3317 | cur_msp = NULL((void*)0); | |||
| 3318 | } | |||
| 3319 | } | |||
| 3320 | ||||
| 3321 | if (prev_msp && prev_msp->last_frame >= cur_frame_num) { | |||
| 3322 | if (prev_msp->last_frame == cur_frame_num) { | |||
| 3323 | /* this payload contains part of previous MSP (contains EoMSP) */ | |||
| 3324 | bytes_belong_to_prev_msp = prev_msp->end_offset_at_last_frame - offset; | |||
| 3325 | } else { /* if (prev_msp->last_frame > cur_frame_num) */ | |||
| 3326 | /* this payload all belongs to previous MSP */ | |||
| 3327 | bytes_belong_to_prev_msp = length; | |||
| 3328 | need_more = true1; | |||
| 3329 | } | |||
| 3330 | reassembly_id = prev_msp->streaming_reassembly_id; | |||
| 3331 | } | |||
| 3332 | if (reassembly_info->frame_num_frag_offset_map) { | |||
| 3333 | frag_offset = GPOINTER_TO_UINT(wmem_map_lookup(reassembly_info->frame_num_frag_offset_map, &cur_frame_num))((guint) (gulong) (wmem_map_lookup(reassembly_info->frame_num_frag_offset_map , &cur_frame_num))); | |||
| 3334 | } | |||
| 3335 | } | |||
| 3336 | ||||
| 3337 | /* handling EoMSP or MoMSP (entire payload being middle part of a MSP) */ | |||
| 3338 | while (bytes_belong_to_prev_msp > 0) { | |||
| 3339 | tvbuff_t* reassembled_tvb = NULL((void*)0); | |||
| 3340 | DISSECTOR_ASSERT(reassembly_id > 0)((void) ((reassembly_id > 0) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3340, "reassembly_id > 0")))); | |||
| 3341 | pinfo->can_desegment = 2; /* this will be decreased one while passing to subdissector */ | |||
| 3342 | pinfo->desegment_offset = 0; | |||
| 3343 | pinfo->desegment_len = 0; | |||
| 3344 | ||||
| 3345 | head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id, NULL((void*)0), | |||
| 3346 | frag_offset, bytes_belong_to_prev_msp, need_more); | |||
| 3347 | ||||
| 3348 | if (head) { | |||
| 3349 | if (frag_hf_items->hf_reassembled_in) { | |||
| 3350 | proto_item_set_generated( | |||
| 3351 | proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in), tvb, offset, | |||
| 3352 | bytes_belong_to_prev_msp, head->reassembled_in) | |||
| 3353 | ); | |||
| 3354 | } | |||
| 3355 | ||||
| 3356 | if (!need_more) { | |||
| 3357 | reassembled_tvb = process_reassembled_data(tvb, offset, pinfo, | |||
| 3358 | wmem_strdup_printf(pinfo->pool, "Reassembled %s", label), | |||
| 3359 | head, frag_hf_items, NULL((void*)0), reassembled_tree); | |||
| 3360 | } | |||
| 3361 | } | |||
| 3362 | ||||
| 3363 | proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset, | |||
| 3364 | bytes_belong_to_prev_msp, NULL((void*)0), "%s Segment data (%u byte%s)", label, | |||
| 3365 | bytes_belong_to_prev_msp, plurality(bytes_belong_to_prev_msp, "", "s")((bytes_belong_to_prev_msp) == 1 ? ("") : ("s"))); | |||
| 3366 | ||||
| 3367 | if (reassembled_tvb) { | |||
| 3368 | /* normally, this stage will dissect one or more completed pdus */ | |||
| 3369 | /* Note, don't call_dissector_with_data because sometime the pinfo->curr_layer_num will changed | |||
| 3370 | * after calling that will make reassembly failed! */ | |||
| 3371 | call_dissector_only(subdissector_handle, reassembled_tvb, pinfo, subdissector_tree, subdissector_data); | |||
| 3372 | } | |||
| 3373 | ||||
| 3374 | if (pinfo->desegment_len) { | |||
| 3375 | /* that must only happen during first scan the reassembly_info->prev_deseg_len might be only the | |||
| 3376 | * head length of entire message. */ | |||
| 3377 | DISSECTOR_ASSERT(!PINFO_FD_VISITED(pinfo))((void) ((!((pinfo)->fd->visited)) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3377, "!((pinfo)->fd->visited)")))); | |||
| 3378 | DISSECTOR_ASSERT_HINT(pinfo->desegment_len != DESEGMENT_UNTIL_FIN, "Subdissector MUST NOT "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : ( proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3380, "pinfo->desegment_len != 0x0ffffffe" , "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to " " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined." )))) | |||
| 3379 | "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : ( proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3380, "pinfo->desegment_len != 0x0ffffffe" , "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to " " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined." )))) | |||
| 3380 | " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined.")((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : ( proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3380, "pinfo->desegment_len != 0x0ffffffe" , "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to " " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined." )))); | |||
| 3381 | ||||
| 3382 | if (pinfo->desegment_offset > 0) { | |||
| 3383 | DISSECTOR_ASSERT_HINT(pinfo->desegment_offset > reassembly_info->last_msp->length((void) ((pinfo->desegment_offset > reassembly_info-> last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp ) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3387, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp" , wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)." , pinfo->desegment_offset, reassembly_info->last_msp-> length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp ))))) | |||
| 3384 | && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp,((void) ((pinfo->desegment_offset > reassembly_info-> last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp ) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3387, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp" , wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)." , pinfo->desegment_offset, reassembly_info->last_msp-> length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp ))))) | |||
| 3385 | wmem_strdup_printf(pinfo->pool,((void) ((pinfo->desegment_offset > reassembly_info-> last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp ) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3387, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp" , wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)." , pinfo->desegment_offset, reassembly_info->last_msp-> length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp ))))) | |||
| 3386 | "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d).",((void) ((pinfo->desegment_offset > reassembly_info-> last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp ) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3387, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp" , wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)." , pinfo->desegment_offset, reassembly_info->last_msp-> length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp ))))) | |||
| 3387 | pinfo->desegment_offset, reassembly_info->last_msp->length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp))((void) ((pinfo->desegment_offset > reassembly_info-> last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp ) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3387, "pinfo->desegment_offset > reassembly_info->last_msp->length && pinfo->desegment_offset < reassembly_info->last_msp->length + bytes_belong_to_prev_msp" , wmem_strdup_printf(pinfo->pool, "Subdissector MUST NOT set pinfo->desegment_offset(%d) in previous or next part of MSP, must between (%d, %d)." , pinfo->desegment_offset, reassembly_info->last_msp-> length, reassembly_info->last_msp->length + bytes_belong_to_prev_msp ))))); | |||
| 3388 | ||||
| 3389 | /* shorten the bytes_belong_to_prev_msp and just truncate the reassembled tvb */ | |||
| 3390 | bytes_belong_to_prev_msp = pinfo->desegment_offset - reassembly_info->last_msp->length; | |||
| 3391 | fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), pinfo->desegment_offset); | |||
| 3392 | found_BoMSP = true1; | |||
| 3393 | } else { | |||
| 3394 | if (pinfo->desegment_len == DESEGMENT_ONE_MORE_SEGMENT0x0fffffff) { | |||
| 3395 | /* just need more bytes, all remaining bytes belongs to previous MSP (to run fragment_add again) */ | |||
| 3396 | bytes_belong_to_prev_msp = length; | |||
| 3397 | } | |||
| 3398 | ||||
| 3399 | /* Remove the data added by previous fragment_add(), and reopen fragments for adding more bytes. */ | |||
| 3400 | fragment_truncate(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0), reassembly_info->last_msp->length); | |||
| 3401 | fragment_set_partial_reassembly(&streaming_reassembly_table, pinfo, reassembly_id, NULL((void*)0)); | |||
| 3402 | ||||
| 3403 | reassembly_info->prev_deseg_len = bytes_belong_to_prev_msp + pinfo->desegment_len; | |||
| 3404 | bytes_belong_to_prev_msp = MIN(reassembly_info->prev_deseg_len, length)(((reassembly_info->prev_deseg_len) < (length)) ? (reassembly_info ->prev_deseg_len) : (length)); | |||
| 3405 | reassembly_info->prev_deseg_len -= bytes_belong_to_prev_msp; | |||
| 3406 | need_more = (reassembly_info->prev_deseg_len > 0); | |||
| 3407 | continue; | |||
| 3408 | } | |||
| 3409 | } | |||
| 3410 | ||||
| 3411 | if (pinfo->desegment_len == 0 || found_BoMSP) { | |||
| 3412 | /* We will arrive here, only when the MSP is defragmented and dissected or this | |||
| 3413 | * payload all belongs to previous MSP (only fragment_add() with need_more=true called) | |||
| 3414 | * or BoMSP is parsed while pinfo->desegment_offset > 0 and pinfo->desegment_len != 0 | |||
| 3415 | */ | |||
| 3416 | offset += bytes_belong_to_prev_msp; | |||
| 3417 | length -= bytes_belong_to_prev_msp; | |||
| 3418 | DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3418, "length >= 0")))); | |||
| 3419 | if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) { | |||
| 3420 | reassembly_info->last_msp->length += bytes_belong_to_prev_msp; | |||
| 3421 | } | |||
| 3422 | ||||
| 3423 | if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited) && reassembled_tvb) { | |||
| 3424 | /* completed current msp */ | |||
| 3425 | reassembly_info->last_msp->last_frame = cur_frame_num; | |||
| 3426 | reassembly_info->last_msp->end_offset_at_last_frame = offset; | |||
| 3427 | reassembly_info->prev_deseg_len = pinfo->desegment_len; | |||
| 3428 | } | |||
| 3429 | bytes_belong_to_prev_msp = 0; /* break */ | |||
| 3430 | } | |||
| 3431 | } | |||
| 3432 | ||||
| 3433 | /* to find and handle OmNFP, and find BoMSP at first scan. */ | |||
| 3434 | if (length > 0 && !found_BoMSP) { | |||
| 3435 | if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) { | |||
| 3436 | /* It is first scan, to dissect remaining bytes to find whether it is OmNFP only, or BoMSP only or OmNFP + BoMSP. */ | |||
| 3437 | datalen = length; | |||
| 3438 | DISSECTOR_ASSERT(cur_msp == NULL)((void) ((cur_msp == ((void*)0)) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3438, "cur_msp == ((void*)0)")))); | |||
| 3439 | } else { | |||
| 3440 | /* Not first scan */ | |||
| 3441 | if (cur_msp) { | |||
| 3442 | /* There's a BoMSP. Let's calculate the length of OmNFP between EoMSP and BoMSP */ | |||
| 3443 | datalen = cur_msp->start_offset_at_first_frame - offset; /* if result is zero that means no OmNFP */ | |||
| 3444 | } else { | |||
| 3445 | /* This payload is not a beginning of MSP. The remaining bytes all belong to OmNFP without BoMSP */ | |||
| 3446 | datalen = length; | |||
| 3447 | } | |||
| 3448 | } | |||
| 3449 | DISSECTOR_ASSERT(datalen >= 0)((void) ((datalen >= 0) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3449, "datalen >= 0")))); | |||
| 3450 | ||||
| 3451 | /* Dissect the remaining of this payload. If (datalen == 0) means remaining only have one BoMSP without OmNFP. */ | |||
| 3452 | if (datalen > 0) { | |||
| 3453 | /* we dissect if it is not dissected before or it is a non-fragment pdu (between two multisegment pdus) */ | |||
| 3454 | pinfo->can_desegment = 2; | |||
| 3455 | pinfo->desegment_offset = 0; | |||
| 3456 | pinfo->desegment_len = 0; | |||
| 3457 | ||||
| 3458 | call_dissector_only(subdissector_handle, tvb_new_subset_length(tvb, offset, datalen), | |||
| 3459 | pinfo, subdissector_tree, subdissector_data); | |||
| 3460 | ||||
| 3461 | if (pinfo->desegment_len) { | |||
| 3462 | DISSECTOR_ASSERT_HINT(pinfo->desegment_len != DESEGMENT_UNTIL_FIN, "Subdissector MUST NOT "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : ( proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3464, "pinfo->desegment_len != 0x0ffffffe" , "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to " " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined." )))) | |||
| 3463 | "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to "((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : ( proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3464, "pinfo->desegment_len != 0x0ffffffe" , "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to " " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined." )))) | |||
| 3464 | " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined.")((void) ((pinfo->desegment_len != 0x0ffffffe) ? (void)0 : ( proto_report_dissector_bug("%s:%u: failed assertion \"%s\" (%s)" , "epan/reassemble.c", 3464, "pinfo->desegment_len != 0x0ffffffe" , "Subdissector MUST NOT " "set pinfo->desegment_len to DESEGMENT_UNTIL_FIN. Instead, it can set pinfo->desegment_len to " " DESEGMENT_ONE_MORE_SEGMENT or the length of head if the length of entire message is not able to be determined." )))); | |||
| 3465 | /* only happen during first scan */ | |||
| 3466 | DISSECTOR_ASSERT(!PINFO_FD_VISITED(pinfo) && datalen == length)((void) ((!((pinfo)->fd->visited) && datalen == length) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\"" , "epan/reassemble.c", 3466, "!((pinfo)->fd->visited) && datalen == length" )))); | |||
| 3467 | offset += pinfo->desegment_offset; | |||
| 3468 | length -= pinfo->desegment_offset; | |||
| 3469 | } else { | |||
| 3470 | /* all remaining bytes are consumed by subdissector */ | |||
| 3471 | offset += datalen; | |||
| 3472 | length -= datalen; | |||
| 3473 | } | |||
| 3474 | if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) { | |||
| 3475 | reassembly_info->prev_deseg_len = pinfo->desegment_len; | |||
| 3476 | } | |||
| 3477 | } /* else all remaining bytes (BoMSP) belong to a new MSP */ | |||
| 3478 | DISSECTOR_ASSERT(length >= 0)((void) ((length >= 0) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/reassemble.c", 3478, "length >= 0")))); | |||
| 3479 | } | |||
| 3480 | ||||
| 3481 | /* handling BoMSP */ | |||
| 3482 | if (length > 0) { | |||
| 3483 | col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ", "[%s segment of a reassembled PDU] ", label); | |||
| 3484 | if (!PINFO_FD_VISITED(pinfo)((pinfo)->fd->visited)) { | |||
| 3485 | /* create a msp for current frame during first scan */ | |||
| 3486 | cur_msp = wmem_new0(wmem_file_scope(), multisegment_pdu_t)((multisegment_pdu_t*)wmem_alloc0((wmem_file_scope()), sizeof (multisegment_pdu_t))); | |||
| 3487 | cur_msp->first_frame = cur_frame_num; | |||
| 3488 | cur_msp->last_frame = UINT64_MAX(18446744073709551615UL); | |||
| 3489 | cur_msp->start_offset_at_first_frame = offset; | |||
| 3490 | cur_msp->length = length; | |||
| 3491 | cur_msp->streaming_reassembly_id = reassembly_id = create_streaming_reassembly_id(); | |||
| 3492 | cur_msp->prev_msp = reassembly_info->last_msp; | |||
| 3493 | reassembly_info->last_msp = cur_msp; | |||
| 3494 | if (reassembly_info->multisegment_pdus == NULL((void*)0)) { | |||
| 3495 | reassembly_info->multisegment_pdus = wmem_map_new(wmem_file_scope(), g_int64_hash, g_int64_equal); | |||
| 3496 | } | |||
| 3497 | frame_ptr = (uint64_t*)wmem_memdup(wmem_file_scope(), &cur_frame_num, sizeof(uint64_t)); | |||
| 3498 | wmem_map_insert(reassembly_info->multisegment_pdus, frame_ptr, cur_msp); | |||
| 3499 | } else { | |||
| 3500 | DISSECTOR_ASSERT(cur_msp && cur_msp->start_offset_at_first_frame == offset)((void) ((cur_msp && cur_msp->start_offset_at_first_frame == offset) ? (void)0 : (proto_report_dissector_bug("%s:%u: failed assertion \"%s\"" , "epan/reassemble.c", 3500, "cur_msp && cur_msp->start_offset_at_first_frame == offset" )))); | |||
| 3501 | reassembly_id = cur_msp->streaming_reassembly_id; | |||
| 3502 | } | |||
| 3503 | /* add first fragment of the new MSP to reassembly table */ | |||
| 3504 | head = fragment_add(&streaming_reassembly_table, tvb, offset, pinfo, reassembly_id, | |||
| 3505 | NULL((void*)0), 0, length, true1); | |||
| 3506 | ||||
| 3507 | if (head && frag_hf_items->hf_reassembled_in) { | |||
| 3508 | proto_item_set_generated( | |||
| 3509 | proto_tree_add_uint(segment_tree, *(frag_hf_items->hf_reassembled_in), | |||
| 3510 | tvb, offset, length, head->reassembled_in) | |||
| 3511 | ); | |||
| 3512 | } | |||
| 3513 | proto_tree_add_bytes_format(segment_tree, hf_segment_data, tvb, offset, length, | |||
| 3514 | NULL((void*)0), "%s Segment data (%u byte%s)", label, length, plurality(length, "", "s")((length) == 1 ? ("") : ("s"))); | |||
| 3515 | } | |||
| 3516 | ||||
| 3517 | pinfo->can_desegment = save_can_desegment; | |||
| 3518 | pinfo->desegment_offset = save_desegment_offset; | |||
| 3519 | pinfo->desegment_len = save_desegment_len; | |||
| 3520 | ||||
| 3521 | return orig_length; | |||
| 3522 | } | |||
| 3523 | ||||
| 3524 | int | |||
| 3525 | additional_bytes_expected_to_complete_reassembly(streaming_reassembly_info_t* reassembly_info) | |||
| 3526 | { | |||
| 3527 | return reassembly_info->prev_deseg_len; | |||
| 3528 | } | |||
| 3529 | ||||
| 3530 | /* | |||
| 3531 | * Editor modelines - https://www.wireshark.org/tools/modelines.html | |||
| 3532 | * | |||
| 3533 | * Local variables: | |||
| 3534 | * c-basic-offset: 8 | |||
| 3535 | * tab-width: 8 | |||
| 3536 | * indent-tabs-mode: t | |||
| 3537 | * End: | |||
| 3538 | * | |||
| 3539 | * vi: set shiftwidth=8 tabstop=8 noexpandtab: | |||
| 3540 | * :indentSize=8:tabSize=8:noTabs=false: | |||
| 3541 | */ |