| File: | epan/dissectors/packet-knxip_decrypt.c |
| Warning: | line 780, column 1 Opened stream never closed. Potential resource leak |
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| 1 | /* packet-knxip_decrypt.c | |||
| 2 | * Decryption keys and decryption functions for KNX/IP Dissector | |||
| 3 | * Copyright 2018, ise GmbH <Ralf.Nasilowski@ise.de> | |||
| 4 | * | |||
| 5 | * Wireshark - Network traffic analyzer | |||
| 6 | * By Gerald Combs <gerald@wireshark.org> | |||
| 7 | * Copyright 1998 Gerald Combs | |||
| 8 | * | |||
| 9 | * SPDX-License-Identifier: GPL-2.0-or-later | |||
| 10 | */ | |||
| 11 | ||||
| 12 | #include "config.h" | |||
| 13 | ||||
| 14 | #define WS_LOG_DOMAIN"packet-knxip" "packet-knxip" | |||
| 15 | ||||
| 16 | #include <wsutil/file_util.h> | |||
| 17 | #include <epan/proto.h> | |||
| 18 | #include "packet-knxip_decrypt.h" | |||
| 19 | #include <epan/wmem_scopes.h> | |||
| 20 | #include <wsutil/wsgcrypt.h> | |||
| 21 | #include <wsutil/strtoi.h> | |||
| 22 | #include <wsutil/wslog.h> | |||
| 23 | #include <wsutil/inet_addr.h> | |||
| 24 | #include <libxml/tree.h> | |||
| 25 | #include <libxml/parser.h> | |||
| 26 | #include <libxml/xpath.h> | |||
| 27 | ||||
| 28 | #define TEXT_BUFFER_SIZE128 128 | |||
| 29 | ||||
| 30 | #define IPA_SIZE4 4 // = size of IPv4 address | |||
| 31 | ||||
| 32 | #define BASE64_KNX_KEY_LENGTH24 24 // = length of base64 encoded KNX key | |||
| 33 | ||||
| 34 | struct knx_keyring_mca_keys* knx_keyring_mca_keys; | |||
| 35 | struct knx_keyring_ga_keys* knx_keyring_ga_keys; | |||
| 36 | struct knx_keyring_ga_senders* knx_keyring_ga_senders; | |||
| 37 | struct knx_keyring_ia_keys* knx_keyring_ia_keys; | |||
| 38 | struct knx_keyring_ia_seqs* knx_keyring_ia_seqs; | |||
| 39 | ||||
| 40 | // Encrypt 16-byte block via AES | |||
| 41 | static void encrypt_block( const uint8_t key[ KNX_KEY_LENGTH16 ], const uint8_t plain[ KNX_KEY_LENGTH16 ], uint8_t p_crypt[ KNX_KEY_LENGTH16 ] ) | |||
| 42 | { | |||
| 43 | gcry_cipher_hd_t cryptor = NULL((void*)0); | |||
| 44 | gcry_cipher_open( &cryptor, GCRY_CIPHER_AES128GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CBC, 0 ); | |||
| 45 | gcry_cipher_setkey( cryptor, key, KNX_KEY_LENGTH16 ); | |||
| 46 | gcry_cipher_encrypt( cryptor, p_crypt, KNX_KEY_LENGTH16, plain, KNX_KEY_LENGTH16 ); | |||
| 47 | gcry_cipher_close( cryptor ); | |||
| 48 | } | |||
| 49 | ||||
| 50 | // Create B_0 for CBC-MAC | |||
| 51 | static void build_b0( uint8_t p_result[ KNX_KEY_LENGTH16 ], const uint8_t* nonce, uint8_t nonce_length ) | |||
| 52 | { | |||
| 53 | DISSECTOR_ASSERT( nonce_length <= KNX_KEY_LENGTH )((void) ((nonce_length <= 16) ? (void)0 : (proto_report_dissector_bug ("%s:%u: failed assertion \"%s\"", "epan/dissectors/packet-knxip_decrypt.c" , 53, "nonce_length <= 16")))); | |||
| 54 | if( nonce_length ) memcpy( p_result, nonce, nonce_length ); | |||
| 55 | memset( p_result + nonce_length, 0, KNX_KEY_LENGTH16 - nonce_length ); | |||
| 56 | } | |||
| 57 | ||||
| 58 | // Create Ctr_0 for CCM encryption/decryption | |||
| 59 | static void build_ctr0( uint8_t p_result[ KNX_KEY_LENGTH16 ], const uint8_t* nonce, uint8_t nonce_length ) | |||
| 60 | { | |||
| 61 | build_b0( p_result, nonce, nonce_length ); | |||
| 62 | p_result[ KNX_KEY_LENGTH16 - 2 ] = 0xFF; | |||
| 63 | } | |||
| 64 | ||||
| 65 | // Calculate MAC for KNX IP Security or KNX Data Security | |||
| 66 | void knx_ccm_calc_cbc_mac(uint8_t p_mac[ KNX_KEY_LENGTH16 ], const uint8_t key[ KNX_KEY_LENGTH16 ], | |||
| 67 | const uint8_t* a_bytes, int a_length, const uint8_t* p_bytes, int p_length, | |||
| 68 | const uint8_t b_0[ KNX_KEY_LENGTH16 ] ) | |||
| 69 | { | |||
| 70 | uint8_t plain[ KNX_KEY_LENGTH16 ]; | |||
| 71 | uint8_t b_pos; | |||
| 72 | ||||
| 73 | // Add B_0 | |||
| 74 | memcpy( plain, b_0, KNX_KEY_LENGTH16 ); | |||
| 75 | encrypt_block( key, plain, p_mac ); | |||
| 76 | ||||
| 77 | // Add a_length | |||
| 78 | plain[ 0 ] = (uint8_t) ((a_length >> 8) ^ p_mac[ 0 ]); | |||
| 79 | plain[ 1 ] = (uint8_t) ((a_length & 0xFF) ^ p_mac[ 1 ]); | |||
| 80 | b_pos = 2; | |||
| 81 | ||||
| 82 | // Add a_bytes directly followed by p_bytes | |||
| 83 | while( a_length || p_length ) | |||
| 84 | { | |||
| 85 | while( a_length && b_pos < KNX_KEY_LENGTH16 ) | |||
| 86 | { | |||
| 87 | plain[ b_pos ] = *a_bytes++ ^ p_mac[ b_pos ]; | |||
| 88 | --a_length; | |||
| 89 | ++b_pos; | |||
| 90 | } | |||
| 91 | ||||
| 92 | while( p_length && b_pos < KNX_KEY_LENGTH16 ) | |||
| 93 | { | |||
| 94 | plain[ b_pos ] = *p_bytes++ ^ p_mac[ b_pos ]; | |||
| 95 | --p_length; | |||
| 96 | ++b_pos; | |||
| 97 | } | |||
| 98 | ||||
| 99 | while( b_pos < KNX_KEY_LENGTH16 ) | |||
| 100 | { | |||
| 101 | plain[ b_pos ] = p_mac[ b_pos ]; | |||
| 102 | ++b_pos; | |||
| 103 | } | |||
| 104 | ||||
| 105 | encrypt_block( key, plain, p_mac ); | |||
| 106 | ||||
| 107 | b_pos = 0; | |||
| 108 | } | |||
| 109 | } | |||
| 110 | ||||
| 111 | // Calculate MAC for KNX IP Security, using 6-byte Sequence ID | |||
| 112 | void knxip_ccm_calc_cbc_mac( uint8_t p_mac[ KNX_KEY_LENGTH16 ], const uint8_t key[ KNX_KEY_LENGTH16 ], | |||
| 113 | const uint8_t* a_bytes, int a_length, const uint8_t* p_bytes, int p_length, | |||
| 114 | const uint8_t* nonce, uint8_t nonce_length ) | |||
| 115 | { | |||
| 116 | uint8_t b_0[ KNX_KEY_LENGTH16 ]; | |||
| 117 | build_b0( b_0, nonce, nonce_length ); | |||
| 118 | b_0[ KNX_KEY_LENGTH16 - 2 ] = (uint8_t) (p_length >> 8); | |||
| 119 | b_0[ KNX_KEY_LENGTH16 - 1 ] = (uint8_t) (p_length & 0xFF); | |||
| 120 | knx_ccm_calc_cbc_mac( p_mac, key, a_bytes, a_length, p_bytes, p_length, b_0 ); | |||
| 121 | } | |||
| 122 | ||||
| 123 | // Encrypt for KNX IP Security or KNX Data Security | |||
| 124 | uint8_t* knx_ccm_encrypt( uint8_t* p_result, const uint8_t key[ KNX_KEY_LENGTH16 ], const uint8_t* p_bytes, int p_length, | |||
| 125 | const uint8_t* mac, uint8_t mac_length, const uint8_t ctr_0[ KNX_KEY_LENGTH16 ], uint8_t s0_bytes_used_for_mac ) | |||
| 126 | { | |||
| 127 | if( p_length >= 0 && !(p_length && !p_bytes) ) | |||
| 128 | { | |||
| 129 | // NB: mac_length = 16 (for IP Security), or 4 (for Data Security) | |||
| 130 | ||||
| 131 | uint8_t* result = p_result ? p_result : (uint8_t*) wmem_alloc( wmem_packet_scope(), p_length + mac_length ); | |||
| 132 | ||||
| 133 | uint8_t* dest = result; | |||
| 134 | ||||
| 135 | uint8_t ctr[ KNX_KEY_LENGTH16 ]; | |||
| 136 | uint8_t mask[ KNX_KEY_LENGTH16 ]; | |||
| 137 | uint8_t mask_0[ KNX_KEY_LENGTH16 ]; | |||
| 138 | uint8_t b_pos; | |||
| 139 | ||||
| 140 | // Encrypt ctr_0 for mac | |||
| 141 | memcpy( ctr, ctr_0, KNX_KEY_LENGTH16 ); | |||
| 142 | encrypt_block( key, ctr, mask_0 ); | |||
| 143 | ||||
| 144 | // Encrypt p_bytes with rest of S_0, only if mac_length < 16. | |||
| 145 | b_pos = s0_bytes_used_for_mac; | |||
| 146 | while (p_length && b_pos < KNX_KEY_LENGTH16 ) | |||
| 147 | { | |||
| 148 | *dest++ = mask_0[b_pos++] ^ *p_bytes++; | |||
| 149 | --p_length; | |||
| 150 | } | |||
| 151 | ||||
| 152 | // Encrypt p_bytes | |||
| 153 | while( p_length ) | |||
| 154 | { | |||
| 155 | // Increment and encrypt ctr | |||
| 156 | ++ctr[ KNX_KEY_LENGTH16 - 1 ]; | |||
| 157 | encrypt_block( key, ctr, mask ); | |||
| 158 | ||||
| 159 | // Encrypt input block via encrypted ctr | |||
| 160 | b_pos = 0; | |||
| 161 | while( p_length && b_pos < KNX_KEY_LENGTH16 ) | |||
| 162 | { | |||
| 163 | *dest++ = mask[ b_pos++] ^ *p_bytes++; | |||
| 164 | --p_length; | |||
| 165 | } | |||
| 166 | } | |||
| 167 | ||||
| 168 | if( mac ) | |||
| 169 | { | |||
| 170 | if( mac_length > KNX_KEY_LENGTH16 ) | |||
| 171 | { | |||
| 172 | mac_length = KNX_KEY_LENGTH16; | |||
| 173 | } | |||
| 174 | ||||
| 175 | // Encrypt and append mac | |||
| 176 | b_pos = 0; | |||
| 177 | while( mac_length ) | |||
| 178 | { | |||
| 179 | *dest++ = mask_0[ b_pos++] ^ *mac++; | |||
| 180 | --mac_length; | |||
| 181 | } | |||
| 182 | } | |||
| 183 | ||||
| 184 | return result; | |||
| 185 | } | |||
| 186 | ||||
| 187 | return NULL((void*)0); | |||
| 188 | } | |||
| 189 | ||||
| 190 | // Encrypt for KNX IP Security (with 16-byte MAC and Nonce based on 6-byte Sequence ID) | |||
| 191 | uint8_t* knxip_ccm_encrypt( uint8_t* p_result, const uint8_t key[ KNX_KEY_LENGTH16 ], const uint8_t* p_bytes, int p_length, | |||
| 192 | const uint8_t mac[KNX_KEY_LENGTH16], const uint8_t* nonce, uint8_t nonce_length ) | |||
| 193 | { | |||
| 194 | uint8_t ctr_0[ KNX_KEY_LENGTH16 ]; | |||
| 195 | build_ctr0( ctr_0, nonce, nonce_length ); | |||
| 196 | return knx_ccm_encrypt( p_result, key, p_bytes, p_length, mac, KNX_KEY_LENGTH16, ctr_0, KNX_KEY_LENGTH16 ); | |||
| 197 | } | |||
| 198 | ||||
| 199 | // Decrypt for KNX-IP Security (with 16-byte MAC and Nonce based on 6-byte Sequence ID) | |||
| 200 | uint8_t* knxip_ccm_decrypt( uint8_t* p_result, const uint8_t key[ KNX_KEY_LENGTH16 ], const uint8_t* crypt, int crypt_length, | |||
| 201 | const uint8_t* nonce, uint8_t nonce_length ) | |||
| 202 | { | |||
| 203 | int p_length = crypt_length - KNX_KEY_LENGTH16; | |||
| 204 | uint8_t ctr_0[ KNX_KEY_LENGTH16 ]; | |||
| 205 | build_ctr0( ctr_0, nonce, nonce_length ); | |||
| 206 | return knx_ccm_encrypt( p_result, key, crypt, p_length, crypt + p_length, KNX_KEY_LENGTH16, ctr_0, KNX_KEY_LENGTH16 ); | |||
| 207 | } | |||
| 208 | ||||
| 209 | static void fprintf_hex( FILE* f, const uint8_t* data, uint8_t length ) | |||
| 210 | { | |||
| 211 | for( ; length; --length ) fprintf( f, " %02X", *data++ ); | |||
| 212 | fputc( '\n', f ); | |||
| 213 | } | |||
| 214 | ||||
| 215 | static void clear_keyring_data( void ) | |||
| 216 | { | |||
| 217 | while( knx_keyring_mca_keys ) | |||
| 218 | { | |||
| 219 | struct knx_keyring_mca_keys* mca_key = knx_keyring_mca_keys; | |||
| 220 | knx_keyring_mca_keys = mca_key->next; | |||
| 221 | wmem_free( wmem_epan_scope(), mca_key ); | |||
| 222 | } | |||
| 223 | ||||
| 224 | while( knx_keyring_ga_keys ) | |||
| 225 | { | |||
| 226 | struct knx_keyring_ga_keys* ga_key = knx_keyring_ga_keys; | |||
| 227 | knx_keyring_ga_keys = ga_key->next; | |||
| 228 | wmem_free( wmem_epan_scope(), ga_key ); | |||
| 229 | } | |||
| 230 | ||||
| 231 | while( knx_keyring_ga_senders ) | |||
| 232 | { | |||
| 233 | struct knx_keyring_ga_senders* ga_sender = knx_keyring_ga_senders; | |||
| 234 | knx_keyring_ga_senders = ga_sender->next; | |||
| 235 | wmem_free( wmem_epan_scope(), ga_sender ); | |||
| 236 | } | |||
| 237 | ||||
| 238 | while( knx_keyring_ia_keys ) | |||
| 239 | { | |||
| 240 | struct knx_keyring_ia_keys* ia_key = knx_keyring_ia_keys; | |||
| 241 | knx_keyring_ia_keys = ia_key->next; | |||
| 242 | wmem_free( wmem_epan_scope(), ia_key ); | |||
| 243 | } | |||
| 244 | ||||
| 245 | while( knx_keyring_ia_seqs ) | |||
| 246 | { | |||
| 247 | struct knx_keyring_ia_seqs* ia_seq = knx_keyring_ia_seqs; | |||
| 248 | knx_keyring_ia_seqs = ia_seq->next; | |||
| 249 | wmem_free( wmem_epan_scope(), ia_seq ); | |||
| 250 | } | |||
| 251 | } | |||
| 252 | ||||
| 253 | // Read IP address | |||
| 254 | static void read_ip_addr( uint8_t result[ 4 ], const char* text ) | |||
| 255 | { | |||
| 256 | ws_in4_addr value = 0; | |||
| 257 | if( ws_inet_pton4( text, &value ) ) | |||
| 258 | memcpy( result, &value, 4 ); | |||
| 259 | else | |||
| 260 | memset( result, 0, 4 ); | |||
| 261 | } | |||
| 262 | ||||
| 263 | // Read KNX group address | |||
| 264 | static uint16_t read_ga( const char* text ) | |||
| 265 | { | |||
| 266 | unsigned a[ 3 ]; | |||
| 267 | int n = sscanf( text, "%u/%u/%u", a, a + 1, a + 2 ); | |||
| 268 | return | |||
| 269 | (n == 1) ? (uint16_t) a[ 0 ] : | |||
| 270 | (n == 2) ? (uint16_t) ((a[ 0 ] << 11) | a[ 1 ]) : | |||
| 271 | (n == 3) ? (uint16_t) ((a[ 0 ] << 11) | (a[ 1 ] << 8) | a[ 2 ]) : | |||
| 272 | 0; | |||
| 273 | } | |||
| 274 | ||||
| 275 | // Read KNX individual address | |||
| 276 | static uint16_t read_ia( const char* text ) | |||
| 277 | { | |||
| 278 | unsigned a[ 3 ]; | |||
| 279 | int n = sscanf( text, "%u.%u.%u", a, a + 1, a + 2 ); | |||
| 280 | return | |||
| 281 | (n == 1) ? (uint16_t) a[ 0 ] : | |||
| 282 | (n == 2) ? (uint16_t) ((a[ 0 ] << 8) | a[ 1 ]) : | |||
| 283 | (n == 3) ? (uint16_t) ((a[ 0 ] << 12) | (a[ 1 ] << 8) | a[ 2 ]) : | |||
| 284 | 0; | |||
| 285 | } | |||
| 286 | ||||
| 287 | // Read 6-byte sequence number from decimal representation | |||
| 288 | static uint64_t read_seq( const char* text ) | |||
| 289 | { | |||
| 290 | uint64_t result; | |||
| 291 | return ws_strtou64( text, NULL((void*)0), &result ) ? result : 0; | |||
| 292 | } | |||
| 293 | ||||
| 294 | // Decrypt key | |||
| 295 | static void decrypt_key( uint8_t key[] _U___attribute__((unused)), uint8_t password_hash[] _U___attribute__((unused)), uint8_t created_hash[] _U___attribute__((unused)) ) | |||
| 296 | { | |||
| 297 | // TODO: decrypt as AES128-CBC(key, password_hash, created_hash) | |||
| 298 | } | |||
| 299 | ||||
| 300 | // Decode and decrypt key | |||
| 301 | static void decode_and_decrypt_key( uint8_t key[ BASE64_KNX_KEY_LENGTH24 + 1 ], const char* text, uint8_t password_hash[], uint8_t created_hash[] ) | |||
| 302 | { | |||
| 303 | size_t out_len; | |||
| 304 | snprintf( (char*) key, BASE64_KNX_KEY_LENGTH24 + 1, "%s", text ); | |||
| 305 | g_base64_decode_inplace( (char*) key, &out_len ); | |||
| 306 | decrypt_key( key, password_hash, created_hash ); | |||
| 307 | } | |||
| 308 | ||||
| 309 | // Add MCA <-> key association | |||
| 310 | static void add_mca_key( const uint8_t mca[ IPA_SIZE4 ], const char* text, uint8_t password_hash[], uint8_t created_hash[], FILE* f2 ) | |||
| 311 | { | |||
| 312 | int text_length = (int) strlen( text ); | |||
| 313 | ||||
| 314 | if( text_length == BASE64_KNX_KEY_LENGTH24 ) | |||
| 315 | { | |||
| 316 | uint8_t key[ BASE64_KNX_KEY_LENGTH24 + 1 ]; | |||
| 317 | struct knx_keyring_mca_keys** mca_keys_next; | |||
| 318 | struct knx_keyring_mca_keys* mca_key; | |||
| 319 | ||||
| 320 | decode_and_decrypt_key( key, text, password_hash, created_hash ); | |||
| 321 | ||||
| 322 | mca_keys_next = &knx_keyring_mca_keys; | |||
| 323 | ||||
| 324 | while( (mca_key = *mca_keys_next) != NULL((void*)0) ) | |||
| 325 | { | |||
| 326 | if( memcmp( mca_key->mca, mca, IPA_SIZE4 ) == 0 ) | |||
| 327 | { | |||
| 328 | if( memcmp( mca_key->key, key, KNX_KEY_LENGTH16 ) == 0 ) | |||
| 329 | { | |||
| 330 | return; | |||
| 331 | } | |||
| 332 | } | |||
| 333 | ||||
| 334 | mca_keys_next = &mca_key->next; | |||
| 335 | } | |||
| 336 | ||||
| 337 | if( f2 ) | |||
| 338 | { | |||
| 339 | fprintf( f2, "MCA %u.%u.%u.%u key", mca[ 0 ], mca[ 1 ], mca[ 2 ], mca[ 3 ] ); | |||
| 340 | fprintf_hex( f2, key, KNX_KEY_LENGTH16 ); | |||
| 341 | } | |||
| 342 | ||||
| 343 | mca_key = wmem_new(wmem_epan_scope(), struct knx_keyring_mca_keys)((struct knx_keyring_mca_keys*)wmem_alloc((wmem_epan_scope()) , sizeof(struct knx_keyring_mca_keys))); | |||
| 344 | ||||
| 345 | if( mca_key ) | |||
| 346 | { | |||
| 347 | mca_key->next = NULL((void*)0); | |||
| 348 | memcpy( mca_key->mca, mca, IPA_SIZE4 ); | |||
| 349 | memcpy( mca_key->key, key, KNX_KEY_LENGTH16 ); | |||
| 350 | ||||
| 351 | *mca_keys_next = mca_key; | |||
| 352 | } | |||
| 353 | } | |||
| 354 | } | |||
| 355 | ||||
| 356 | // Add GA <-> key association | |||
| 357 | static void add_ga_key( uint16_t ga, const char* text, uint8_t password_hash[], uint8_t created_hash[], FILE* f2 ) | |||
| 358 | { | |||
| 359 | int text_length = (int) strlen( text ); | |||
| 360 | ||||
| 361 | if( text_length == BASE64_KNX_KEY_LENGTH24 ) | |||
| 362 | { | |||
| 363 | uint8_t key[ BASE64_KNX_KEY_LENGTH24 + 1 ]; | |||
| 364 | struct knx_keyring_ga_keys** ga_keys_next; | |||
| 365 | struct knx_keyring_ga_keys* ga_key; | |||
| 366 | ||||
| 367 | decode_and_decrypt_key( key, text, password_hash, created_hash ); | |||
| 368 | ||||
| 369 | ga_keys_next = &knx_keyring_ga_keys; | |||
| 370 | ||||
| 371 | while( (ga_key = *ga_keys_next) != NULL((void*)0) ) | |||
| 372 | { | |||
| 373 | if( ga_key->ga == ga ) | |||
| 374 | { | |||
| 375 | if( memcmp( ga_key->key, key, KNX_KEY_LENGTH16 ) == 0 ) | |||
| 376 | { | |||
| 377 | return; | |||
| 378 | } | |||
| 379 | } | |||
| 380 | ||||
| 381 | ga_keys_next = &ga_key->next; | |||
| 382 | } | |||
| 383 | ||||
| 384 | if( f2 ) | |||
| 385 | { | |||
| 386 | fprintf( f2, "GA %u/%u/%u key", (ga >> 11) & 0x1F, (ga >> 8) & 0x7, ga & 0xFF ); | |||
| 387 | fprintf_hex( f2, key, KNX_KEY_LENGTH16 ); | |||
| 388 | } | |||
| 389 | ||||
| 390 | ga_key = wmem_new(wmem_epan_scope(), struct knx_keyring_ga_keys)((struct knx_keyring_ga_keys*)wmem_alloc((wmem_epan_scope()), sizeof(struct knx_keyring_ga_keys))); | |||
| 391 | ||||
| 392 | if( ga_key ) | |||
| 393 | { | |||
| 394 | ga_key->next = NULL((void*)0); | |||
| 395 | ga_key->ga = ga; | |||
| 396 | memcpy( ga_key->key, key, KNX_KEY_LENGTH16 ); | |||
| 397 | ||||
| 398 | *ga_keys_next = ga_key; | |||
| 399 | } | |||
| 400 | } | |||
| 401 | } | |||
| 402 | ||||
| 403 | // Add GA <-> sender association | |||
| 404 | static void add_ga_sender( uint16_t ga, const char* text, FILE* f2 ) | |||
| 405 | { | |||
| 406 | uint16_t ia = read_ia( text ); | |||
| 407 | struct knx_keyring_ga_senders** ga_senders_next = &knx_keyring_ga_senders; | |||
| 408 | struct knx_keyring_ga_senders* ga_sender; | |||
| 409 | ||||
| 410 | while( (ga_sender = *ga_senders_next) != NULL((void*)0) ) | |||
| 411 | { | |||
| 412 | if( ga_sender->ga == ga ) | |||
| 413 | { | |||
| 414 | if( ga_sender->ia == ia ) | |||
| 415 | { | |||
| 416 | return; | |||
| 417 | } | |||
| 418 | } | |||
| 419 | ||||
| 420 | ga_senders_next = &ga_sender->next; | |||
| 421 | } | |||
| 422 | ||||
| 423 | if( f2 ) | |||
| 424 | { | |||
| 425 | fprintf( f2, "GA %u/%u/%u sender %u.%u.%u\n", (ga >> 11) & 0x1F, (ga >> 8) & 0x7, ga & 0xFF, (ia >> 12) & 0xF, (ia >> 8) & 0xF, ia & 0xFF ); | |||
| 426 | } | |||
| 427 | ||||
| 428 | ga_sender = wmem_new(wmem_epan_scope(), struct knx_keyring_ga_senders)((struct knx_keyring_ga_senders*)wmem_alloc((wmem_epan_scope( )), sizeof(struct knx_keyring_ga_senders))); | |||
| 429 | ||||
| 430 | if( ga_sender ) | |||
| 431 | { | |||
| 432 | ga_sender->next = NULL((void*)0); | |||
| 433 | ga_sender->ga = ga; | |||
| 434 | ga_sender->ia = ia; | |||
| 435 | ||||
| 436 | *ga_senders_next = ga_sender; | |||
| 437 | } | |||
| 438 | } | |||
| 439 | ||||
| 440 | // Add IA <-> key association | |||
| 441 | static void add_ia_key( uint16_t ia, const char* text, uint8_t password_hash[], uint8_t created_hash[], FILE* f2 ) | |||
| 442 | { | |||
| 443 | int text_length = (int) strlen( text ); | |||
| 444 | ||||
| 445 | if( text_length == BASE64_KNX_KEY_LENGTH24 ) | |||
| 446 | { | |||
| 447 | uint8_t key[ BASE64_KNX_KEY_LENGTH24 + 1 ]; | |||
| 448 | struct knx_keyring_ia_keys** ia_keys_next; | |||
| 449 | struct knx_keyring_ia_keys* ia_key; | |||
| 450 | ||||
| 451 | decode_and_decrypt_key( key, text, password_hash, created_hash ); | |||
| 452 | ||||
| 453 | ia_keys_next = &knx_keyring_ia_keys; | |||
| 454 | ||||
| 455 | while( (ia_key = *ia_keys_next) != NULL((void*)0) ) | |||
| 456 | { | |||
| 457 | if( ia_key->ia == ia ) | |||
| 458 | { | |||
| 459 | if( memcmp( ia_key->key, key, KNX_KEY_LENGTH16 ) == 0 ) | |||
| 460 | { | |||
| 461 | return; | |||
| 462 | } | |||
| 463 | } | |||
| 464 | ||||
| 465 | ia_keys_next = &ia_key->next; | |||
| 466 | } | |||
| 467 | ||||
| 468 | if( f2 ) | |||
| 469 | { | |||
| 470 | fprintf( f2, "IA %u.%u.%u key", (ia >> 12) & 0xF, (ia >> 8) & 0xF, ia & 0xFF ); | |||
| 471 | fprintf_hex( f2, key, KNX_KEY_LENGTH16 ); | |||
| 472 | } | |||
| 473 | ||||
| 474 | ia_key = wmem_new(wmem_epan_scope(), struct knx_keyring_ia_keys)((struct knx_keyring_ia_keys*)wmem_alloc((wmem_epan_scope()), sizeof(struct knx_keyring_ia_keys))); | |||
| 475 | ||||
| 476 | if( ia_key ) | |||
| 477 | { | |||
| 478 | ia_key->next = NULL((void*)0); | |||
| 479 | ia_key->ia = ia; | |||
| 480 | memcpy( ia_key->key, key, KNX_KEY_LENGTH16 ); | |||
| 481 | ||||
| 482 | *ia_keys_next = ia_key; | |||
| 483 | } | |||
| 484 | } | |||
| 485 | } | |||
| 486 | ||||
| 487 | // Add IA <-> sequence number association | |||
| 488 | static void add_ia_seq( uint16_t ia, const char* text, FILE* f2 ) | |||
| 489 | { | |||
| 490 | uint64_t seq = read_seq( text ); | |||
| 491 | ||||
| 492 | struct knx_keyring_ia_seqs** ia_seqs_next = &knx_keyring_ia_seqs; | |||
| 493 | struct knx_keyring_ia_seqs* ia_seq; | |||
| 494 | ||||
| 495 | while( (ia_seq = *ia_seqs_next) != NULL((void*)0) ) | |||
| 496 | { | |||
| 497 | if( ia_seq->ia == ia ) | |||
| 498 | { | |||
| 499 | if( ia_seq->seq == seq ) | |||
| 500 | { | |||
| 501 | return; | |||
| 502 | } | |||
| 503 | } | |||
| 504 | ||||
| 505 | ia_seqs_next = &ia_seq->next; | |||
| 506 | } | |||
| 507 | ||||
| 508 | if( f2 ) | |||
| 509 | { | |||
| 510 | fprintf( f2, "IA %u.%u.%u SeqNr %" PRIu64"l" "u" "\n", (ia >> 12) & 0xF, (ia >> 8) & 0xF, ia & 0xFF, seq ); | |||
| 511 | } | |||
| 512 | ||||
| 513 | ia_seq = wmem_new(wmem_epan_scope(), struct knx_keyring_ia_seqs)((struct knx_keyring_ia_seqs*)wmem_alloc((wmem_epan_scope()), sizeof(struct knx_keyring_ia_seqs))); | |||
| 514 | ||||
| 515 | if( ia_seq ) | |||
| 516 | { | |||
| 517 | ia_seq->next = NULL((void*)0); | |||
| 518 | ia_seq->ia = ia; | |||
| 519 | ia_seq->seq = seq; | |||
| 520 | ||||
| 521 | *ia_seqs_next = ia_seq; | |||
| 522 | } | |||
| 523 | } | |||
| 524 | ||||
| 525 | // Calculate PBKDF2(HMAC-SHA256, password, "1.keyring.ets.knx.org", 65536, 128) | |||
| 526 | static void make_password_hash( uint8_t password_hash[] _U___attribute__((unused)), const char* password _U___attribute__((unused)) ) | |||
| 527 | { | |||
| 528 | // TODO: password_hash = PBKDF2(HMAC-SHA256, password, "1.keyring.ets.knx.org", 65536, 128) | |||
| 529 | } | |||
| 530 | ||||
| 531 | // Calculate MSB128(SHA256(created)) | |||
| 532 | static void make_created_hash( uint8_t created_hash[] _U___attribute__((unused)), const char* created _U___attribute__((unused)) ) | |||
| 533 | { | |||
| 534 | // TODO: created_hash = MSB128(SHA256(created)) | |||
| 535 | } | |||
| 536 | ||||
| 537 | static void read_knx_keyring_xml_backbone_element(xmlNodePtr backbone, uint8_t password_hash[], uint8_t created_hash[], FILE* f2) | |||
| 538 | { | |||
| 539 | bool_Bool address_valid = false0; | |||
| 540 | uint8_t multicast_address[IPA_SIZE4] = { 0 }; | |||
| 541 | ||||
| 542 | /* Parse out the attributes of the Backbone element */ | |||
| 543 | for (xmlAttrPtr attr = backbone->properties; attr; attr = attr->next) | |||
| 544 | { | |||
| 545 | if (xmlStrcmp(attr->name, (const xmlChar*)"MulticastAddress") == 0) | |||
| 546 | { | |||
| 547 | xmlChar* str_address = xmlNodeListGetString(backbone->doc, attr->children, 1); | |||
| 548 | if (str_address != NULL((void*)0)) | |||
| 549 | { | |||
| 550 | read_ip_addr(multicast_address, str_address); | |||
| 551 | address_valid = true1; | |||
| 552 | xmlFree(str_address); | |||
| 553 | } | |||
| 554 | } | |||
| 555 | else if (xmlStrcmp(attr->name, (const xmlChar*)"Key") == 0) | |||
| 556 | { | |||
| 557 | if (address_valid) | |||
| 558 | { | |||
| 559 | xmlChar* str_key = xmlNodeListGetString(backbone->doc, attr->children, 1); | |||
| 560 | if (str_key != NULL((void*)0)) | |||
| 561 | { | |||
| 562 | add_mca_key(multicast_address, str_key, password_hash, created_hash, f2); | |||
| 563 | xmlFree(str_key); | |||
| 564 | } | |||
| 565 | } | |||
| 566 | } | |||
| 567 | } | |||
| 568 | ||||
| 569 | } | |||
| 570 | ||||
| 571 | static void read_knx_keyring_xml_group_element(xmlNodePtr group, uint8_t password_hash[], uint8_t created_hash[], FILE* f2) | |||
| 572 | { | |||
| 573 | bool_Bool address_valid = false0; | |||
| 574 | uint16_t addr = 0; | |||
| 575 | ||||
| 576 | /* Parse out the attributes of the Group element */ | |||
| 577 | for (xmlAttrPtr attr = group->properties; attr; attr = attr->next) | |||
| 578 | { | |||
| 579 | if (xmlStrcmp(attr->name, (const xmlChar*)"Address") == 0) | |||
| 580 | { | |||
| 581 | xmlChar* str_address = xmlNodeListGetString(group->doc, attr->children, 1); | |||
| 582 | if (str_address != NULL((void*)0)) | |||
| 583 | { | |||
| 584 | addr = read_ga(str_address); | |||
| 585 | address_valid = true1; | |||
| 586 | xmlFree(str_address); | |||
| 587 | } | |||
| 588 | } | |||
| 589 | else if (xmlStrcmp(attr->name, (const xmlChar*)"Key") == 0) | |||
| 590 | { | |||
| 591 | if (address_valid) | |||
| 592 | { | |||
| 593 | xmlChar* str_key = xmlNodeListGetString(group->doc, attr->children, 1); | |||
| 594 | add_ga_key(addr, str_key, password_hash, created_hash, f2); | |||
| 595 | xmlFree(str_key); | |||
| 596 | } | |||
| 597 | } | |||
| 598 | else if (xmlStrcmp(attr->name, (const xmlChar*)"Senders") == 0) | |||
| 599 | { | |||
| 600 | if (address_valid) | |||
| 601 | { | |||
| 602 | xmlChar* str_senders = xmlNodeListGetString(group->doc, attr->children, 1); | |||
| 603 | if (str_senders != NULL((void*)0)) | |||
| 604 | { | |||
| 605 | // Add senders given by space separated list of KNX IAs | |||
| 606 | static const char delim[] = " ,"; | |||
| 607 | const char* token = strtok(str_senders, delim); | |||
| 608 | while (token) | |||
| 609 | { | |||
| 610 | add_ga_sender(addr, token, f2); | |||
| 611 | token = strtok(NULL((void*)0), delim); | |||
| 612 | } | |||
| 613 | xmlFree(str_senders); | |||
| 614 | } | |||
| 615 | } | |||
| 616 | } | |||
| 617 | } | |||
| 618 | ||||
| 619 | } | |||
| 620 | ||||
| 621 | static void read_knx_keyring_xml_device_element(xmlNodePtr device, uint8_t password_hash[], uint8_t created_hash[], FILE* f2) | |||
| 622 | { | |||
| 623 | bool_Bool address_valid = false0; | |||
| 624 | uint16_t addr = 0; | |||
| 625 | ||||
| 626 | /* Parse out the attributes of the Device element */ | |||
| 627 | for (xmlAttrPtr attr = device->properties; attr; attr = attr->next) | |||
| 628 | { | |||
| 629 | if (xmlStrcmp(attr->name, (const xmlChar*)"IndividualAddress") == 0) | |||
| 630 | { | |||
| 631 | xmlChar* str_address = xmlNodeListGetString(device->doc, attr->children, 1); | |||
| 632 | if (str_address != NULL((void*)0)) | |||
| 633 | { | |||
| 634 | addr = read_ia(str_address); | |||
| 635 | address_valid = true1; | |||
| 636 | xmlFree(str_address); | |||
| 637 | } | |||
| 638 | } | |||
| 639 | else if (xmlStrcmp(attr->name, (const xmlChar*)"ToolKey") == 0) | |||
| 640 | { | |||
| 641 | if (address_valid) | |||
| 642 | { | |||
| 643 | xmlChar* str_key = xmlNodeListGetString(device->doc, attr->children, 1); | |||
| 644 | if (str_key != NULL((void*)0)) | |||
| 645 | { | |||
| 646 | add_ia_key(addr, str_key, password_hash, created_hash, f2); | |||
| 647 | xmlFree(str_key); | |||
| 648 | } | |||
| 649 | } | |||
| 650 | } | |||
| 651 | else if (xmlStrcmp(attr->name, (const xmlChar*)"SequenceNumber") == 0) | |||
| 652 | { | |||
| 653 | if (address_valid) | |||
| 654 | { | |||
| 655 | xmlChar* str_seq = xmlNodeListGetString(device->doc, attr->children, 1); | |||
| 656 | if (str_seq != NULL((void*)0)) | |||
| 657 | { | |||
| 658 | add_ia_seq(addr, str_seq, f2); | |||
| 659 | xmlFree(str_seq); | |||
| 660 | } | |||
| 661 | } | |||
| 662 | } | |||
| 663 | } | |||
| 664 | } | |||
| 665 | ||||
| 666 | // Read KNX security key info from keyring XML file. | |||
| 667 | // | |||
| 668 | // An example keyring XML file is | |||
| 669 | // "test/keys/knx_keyring.xml". | |||
| 670 | // | |||
| 671 | // Corresponding test is | |||
| 672 | // suite_decryption.case_decrypt_knxip.test_knxip_keyring_xml_import | |||
| 673 | // | |||
| 674 | // Resulting decoded and decrypted 16-byte keys with context info are optionally written to a "key info" text file. | |||
| 675 | // This may be useful, as these keys are not directly available from the keyring XML file . | |||
| 676 | void read_knx_keyring_xml_file(const char* key_file, const char* password, const char* key_info_file) | |||
| 677 | { | |||
| 678 | xmlDocPtr doc; | |||
| 679 | xmlNodePtr root_element = NULL((void*)0); | |||
| 680 | xmlNodePtr key_ring = NULL((void*)0); | |||
| 681 | uint8_t password_hash[KNX_KEY_LENGTH16] = { 0 }; | |||
| 682 | uint8_t created_hash[KNX_KEY_LENGTH16] = {0}; | |||
| 683 | ||||
| 684 | // Clear old keyring data | |||
| 685 | clear_keyring_data(); | |||
| 686 | ||||
| 687 | doc = xmlReadFile(key_file, NULL((void*)0), 0); | |||
| 688 | if (doc == NULL((void*)0)) | |||
| ||||
| 689 | return; | |||
| 690 | ||||
| 691 | root_element = xmlDocGetRootElement(doc); | |||
| 692 | if (root_element == NULL((void*)0)) | |||
| 693 | { | |||
| 694 | xmlFreeDoc(doc); | |||
| 695 | return; | |||
| 696 | } | |||
| 697 | ||||
| 698 | /* Find the Keyring element */ | |||
| 699 | if (xmlStrcmp(root_element->name, (const xmlChar*)"Keyring") == 0) | |||
| 700 | { | |||
| 701 | key_ring = root_element; | |||
| 702 | } | |||
| 703 | else | |||
| 704 | { | |||
| 705 | for (xmlNodePtr cur = root_element->children; cur != NULL((void*)0); cur = cur->next) | |||
| 706 | { | |||
| 707 | if (cur->type == XML_ELEMENT_NODE && xmlStrcmp(cur->name, (const xmlChar*)"Keyring") == 0) | |||
| 708 | { | |||
| 709 | key_ring = cur; | |||
| 710 | break; | |||
| 711 | } | |||
| 712 | } | |||
| 713 | } | |||
| 714 | ||||
| 715 | if (key_ring
| |||
| 716 | return; | |||
| 717 | ||||
| 718 | // Optionally write extracted data to key info file | |||
| 719 | FILE* f2 = (!key_info_file || !*key_info_file) ? NULL((void*)0) : | |||
| 720 | (strcmp( key_info_file, "-" ) == 0) ? stdoutstdout : | |||
| 721 | ws_fopenfopen( key_info_file, "w" ); | |||
| 722 | ||||
| 723 | make_password_hash(password_hash, password); | |||
| 724 | ||||
| 725 | /* Parse out the attributes of the Keyring element */ | |||
| 726 | for (xmlAttrPtr attr = key_ring->properties; attr; attr = attr->next) | |||
| 727 | { | |||
| 728 | if (xmlStrcmp(attr->name, (const xmlChar*)"Created") == 0) | |||
| 729 | { | |||
| 730 | xmlChar* str_created = xmlNodeListGetString(key_ring->doc, attr->children, 1); | |||
| 731 | if (str_created != NULL((void*)0)) | |||
| 732 | { | |||
| 733 | make_created_hash(created_hash, str_created); | |||
| 734 | xmlFree(str_created); | |||
| 735 | } | |||
| 736 | } | |||
| 737 | } | |||
| 738 | ||||
| 739 | /* Parse out subelements of Keyring element */ | |||
| 740 | for (xmlNodePtr cur = key_ring->children; cur != NULL((void*)0); cur = cur->next) | |||
| 741 | { | |||
| 742 | if (cur->type == XML_ELEMENT_NODE && xmlStrcmp(cur->name, (const xmlChar*)"Backbone") == 0) | |||
| 743 | { | |||
| 744 | read_knx_keyring_xml_backbone_element(cur, password_hash, created_hash, f2); | |||
| 745 | } | |||
| 746 | else if (cur->type == XML_ELEMENT_NODE && xmlStrcmp(cur->name, (const xmlChar*)"Interface") == 0) | |||
| 747 | { | |||
| 748 | for (xmlNodePtr group = cur->children; group != NULL((void*)0); group = group->next) | |||
| 749 | { | |||
| 750 | if (group->type == XML_ELEMENT_NODE && xmlStrcmp(group->name, (const xmlChar*)"Group") == 0) | |||
| 751 | { | |||
| 752 | read_knx_keyring_xml_group_element(group, password_hash, created_hash, f2); | |||
| 753 | } | |||
| 754 | } | |||
| 755 | } | |||
| 756 | else if (cur->type == XML_ELEMENT_NODE && xmlStrcmp(cur->name, (const xmlChar*)"GroupAddresses") == 0) | |||
| 757 | { | |||
| 758 | for (xmlNodePtr group = cur->children; group != NULL((void*)0); group = group->next) | |||
| 759 | { | |||
| 760 | if (group->type == XML_ELEMENT_NODE && xmlStrcmp(group->name, (const xmlChar*)"Group") == 0) | |||
| 761 | { | |||
| 762 | read_knx_keyring_xml_group_element(group, password_hash, created_hash, f2); | |||
| 763 | } | |||
| 764 | } | |||
| 765 | } | |||
| 766 | else if (cur->type == XML_ELEMENT_NODE && xmlStrcmp(cur->name, (const xmlChar*)"Devices") == 0) | |||
| 767 | { | |||
| 768 | for (xmlNodePtr device = cur->children; device != NULL((void*)0); device = device->next) | |||
| 769 | { | |||
| 770 | if (device->type == XML_ELEMENT_NODE && xmlStrcmp(device->name, (const xmlChar*)"Device") == 0) | |||
| 771 | { | |||
| 772 | read_knx_keyring_xml_device_element(device, password_hash, created_hash, f2); | |||
| 773 | } | |||
| 774 | } | |||
| 775 | } | |||
| 776 | } | |||
| 777 | ||||
| 778 | if (f2
| |||
| 779 | fclose(f2); | |||
| 780 | } | |||
| ||||
| 781 | ||||
| 782 | /* | |||
| 783 | * Editor modelines - https://www.wireshark.org/tools/modelines.html | |||
| 784 | * | |||
| 785 | * Local variables: | |||
| 786 | * c-basic-offset: 2 | |||
| 787 | * tab-width: 8 | |||
| 788 | * indent-tabs-mode: nil | |||
| 789 | * End: | |||
| 790 | * | |||
| 791 | * vi: set shiftwidth=2 tabstop=8 expandtab: | |||
| 792 | * :indentSize=2:tabSize=8:noTabs=true: | |||
| 793 | */ |