| 1 | /* $Cambridge: exim/src/src/mime.c,v 1.4 2005/02/17 11:58:26 ph10 Exp $ */ |
| 2 | |
| 3 | /************************************************* |
| 4 | * Exim - an Internet mail transport agent * |
| 5 | *************************************************/ |
| 6 | |
| 7 | /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2004 */ |
| 8 | /* License: GPL */ |
| 9 | |
| 10 | #include "exim.h" |
| 11 | #ifdef WITH_CONTENT_SCAN |
| 12 | #include "mime.h" |
| 13 | #include <sys/stat.h> |
| 14 | |
| 15 | FILE *mime_stream = NULL; |
| 16 | uschar *mime_current_boundary = NULL; |
| 17 | |
| 18 | /************************************************* |
| 19 | * set MIME anomaly level + text * |
| 20 | *************************************************/ |
| 21 | |
| 22 | /* Small wrapper to set the two expandables which |
| 23 | give info on detected "problems" in MIME |
| 24 | encodings. Those are defined in mime.h. */ |
| 25 | |
| 26 | void mime_set_anomaly(int level, char *text) { |
| 27 | mime_anomaly_level = level; |
| 28 | mime_anomaly_text = US text; |
| 29 | } |
| 30 | |
| 31 | |
| 32 | /************************************************* |
| 33 | * decode quoted-printable chars * |
| 34 | *************************************************/ |
| 35 | |
| 36 | /* gets called when we hit a = |
| 37 | returns: new pointer position |
| 38 | result code in c: |
| 39 | -2 - decode error |
| 40 | -1 - soft line break, no char |
| 41 | 0-255 - char to write |
| 42 | */ |
| 43 | |
| 44 | unsigned int mime_qp_hstr_i(uschar *cptr) { |
| 45 | unsigned int i, j = 0; |
| 46 | while (cptr && *cptr && isxdigit(*cptr)) { |
| 47 | i = *cptr++ - '0'; |
| 48 | if (9 < i) i -= 7; |
| 49 | j <<= 4; |
| 50 | j |= (i & 0x0f); |
| 51 | } |
| 52 | return(j); |
| 53 | } |
| 54 | |
| 55 | uschar *mime_decode_qp_char(uschar *qp_p,int *c) { |
| 56 | uschar hex[] = {0,0,0}; |
| 57 | int nan = 0; |
| 58 | uschar *initial_pos = qp_p; |
| 59 | |
| 60 | /* advance one char */ |
| 61 | qp_p++; |
| 62 | |
| 63 | REPEAT_FIRST: |
| 64 | if ( (*qp_p == '\t') || (*qp_p == ' ') || (*qp_p == '\r') ) { |
| 65 | /* tab or whitespace may follow |
| 66 | just ignore it, but remember |
| 67 | that this is not a valid hex |
| 68 | encoding any more */ |
| 69 | nan = 1; |
| 70 | qp_p++; |
| 71 | goto REPEAT_FIRST; |
| 72 | } |
| 73 | else if ( (('0' <= *qp_p) && (*qp_p <= '9')) || (('A' <= *qp_p) && (*qp_p <= 'F')) || (('a' <= *qp_p) && (*qp_p <= 'f')) ) { |
| 74 | /* this is a valid hex char, if nan is unset */ |
| 75 | if (nan) { |
| 76 | /* this is illegal */ |
| 77 | *c = -2; |
| 78 | return initial_pos; |
| 79 | } |
| 80 | else { |
| 81 | hex[0] = *qp_p; |
| 82 | qp_p++; |
| 83 | }; |
| 84 | } |
| 85 | else if (*qp_p == '\n') { |
| 86 | /* hit soft line break already, continue */ |
| 87 | *c = -1; |
| 88 | return qp_p; |
| 89 | } |
| 90 | else { |
| 91 | /* illegal char here */ |
| 92 | *c = -2; |
| 93 | return initial_pos; |
| 94 | }; |
| 95 | |
| 96 | if ( (('0' <= *qp_p) && (*qp_p <= '9')) || (('A' <= *qp_p) && (*qp_p <= 'F')) || (('a' <= *qp_p) && (*qp_p <= 'f')) ) { |
| 97 | if (hex[0] > 0) { |
| 98 | hex[1] = *qp_p; |
| 99 | /* do hex conversion */ |
| 100 | *c = mime_qp_hstr_i(hex); |
| 101 | qp_p++; |
| 102 | return qp_p; |
| 103 | } |
| 104 | else { |
| 105 | /* huh ? */ |
| 106 | *c = -2; |
| 107 | return initial_pos; |
| 108 | }; |
| 109 | } |
| 110 | else { |
| 111 | /* illegal char */ |
| 112 | *c = -2; |
| 113 | return initial_pos; |
| 114 | }; |
| 115 | } |
| 116 | |
| 117 | |
| 118 | uschar *mime_parse_line(uschar *buffer, uschar *encoding, int *num_decoded) { |
| 119 | uschar *data = NULL; |
| 120 | |
| 121 | data = (uschar *)malloc(Ustrlen(buffer)+2); |
| 122 | |
| 123 | if (encoding == NULL) { |
| 124 | /* no encoding type at all */ |
| 125 | NO_DECODING: |
| 126 | memcpy(data, buffer, Ustrlen(buffer)); |
| 127 | data[(Ustrlen(buffer))] = 0; |
| 128 | *num_decoded = Ustrlen(data); |
| 129 | return data; |
| 130 | } |
| 131 | else if (Ustrcmp(encoding,"base64") == 0) { |
| 132 | uschar *p = buffer; |
| 133 | int offset = 0; |
| 134 | |
| 135 | /* ----- BASE64 ---------------------------------------------------- */ |
| 136 | /* NULL out '\r' and '\n' chars */ |
| 137 | while (Ustrrchr(p,'\r') != NULL) { |
| 138 | *(Ustrrchr(p,'\r')) = '\0'; |
| 139 | }; |
| 140 | while (Ustrrchr(p,'\n') != NULL) { |
| 141 | *(Ustrrchr(p,'\n')) = '\0'; |
| 142 | }; |
| 143 | |
| 144 | while (*(p+offset) != '\0') { |
| 145 | /* hit illegal char ? */ |
| 146 | if (mime_b64[*(p+offset)] == 128) { |
| 147 | mime_set_anomaly(MIME_ANOMALY_BROKEN_BASE64); |
| 148 | offset++; |
| 149 | } |
| 150 | else { |
| 151 | *p = mime_b64[*(p+offset)]; |
| 152 | p++; |
| 153 | }; |
| 154 | }; |
| 155 | *p = 255; |
| 156 | |
| 157 | /* line is translated, start bit shifting */ |
| 158 | p = buffer; |
| 159 | *num_decoded = 0; |
| 160 | while(*p != 255) { |
| 161 | uschar tmp_c; |
| 162 | |
| 163 | /* byte 0 ---------------------- */ |
| 164 | if (*(p+1) == 255) { |
| 165 | mime_set_anomaly(MIME_ANOMALY_BROKEN_BASE64); |
| 166 | break; |
| 167 | } |
| 168 | data[(*num_decoded)] = *p; |
| 169 | data[(*num_decoded)] <<= 2; |
| 170 | tmp_c = *(p+1); |
| 171 | tmp_c >>= 4; |
| 172 | data[(*num_decoded)] |= tmp_c; |
| 173 | (*num_decoded)++; |
| 174 | p++; |
| 175 | /* byte 1 ---------------------- */ |
| 176 | if (*(p+1) == 255) { |
| 177 | mime_set_anomaly(MIME_ANOMALY_BROKEN_BASE64); |
| 178 | break; |
| 179 | } |
| 180 | data[(*num_decoded)] = *p; |
| 181 | data[(*num_decoded)] <<= 4; |
| 182 | tmp_c = *(p+1); |
| 183 | tmp_c >>= 2; |
| 184 | data[(*num_decoded)] |= tmp_c; |
| 185 | (*num_decoded)++; |
| 186 | p++; |
| 187 | /* byte 2 ---------------------- */ |
| 188 | if (*(p+1) == 255) { |
| 189 | mime_set_anomaly(MIME_ANOMALY_BROKEN_BASE64); |
| 190 | break; |
| 191 | } |
| 192 | data[(*num_decoded)] = *p; |
| 193 | data[(*num_decoded)] <<= 6; |
| 194 | data[(*num_decoded)] |= *(p+1); |
| 195 | (*num_decoded)++; |
| 196 | p+=2; |
| 197 | |
| 198 | }; |
| 199 | return data; |
| 200 | /* ----------------------------------------------------------------- */ |
| 201 | } |
| 202 | else if (Ustrcmp(encoding,"quoted-printable") == 0) { |
| 203 | uschar *p = buffer; |
| 204 | |
| 205 | /* ----- QP -------------------------------------------------------- */ |
| 206 | *num_decoded = 0; |
| 207 | while (*p != 0) { |
| 208 | if (*p == '=') { |
| 209 | int decode_qp_result; |
| 210 | |
| 211 | p = mime_decode_qp_char(p,&decode_qp_result); |
| 212 | |
| 213 | if (decode_qp_result == -2) { |
| 214 | /* Error from decoder. p is unchanged. */ |
| 215 | mime_set_anomaly(MIME_ANOMALY_BROKEN_QP); |
| 216 | data[(*num_decoded)] = '='; |
| 217 | (*num_decoded)++; |
| 218 | p++; |
| 219 | } |
| 220 | else if (decode_qp_result == -1) { |
| 221 | break; |
| 222 | } |
| 223 | else if (decode_qp_result >= 0) { |
| 224 | data[(*num_decoded)] = decode_qp_result; |
| 225 | (*num_decoded)++; |
| 226 | }; |
| 227 | } |
| 228 | else { |
| 229 | data[(*num_decoded)] = *p; |
| 230 | (*num_decoded)++; |
| 231 | p++; |
| 232 | }; |
| 233 | }; |
| 234 | return data; |
| 235 | /* ----------------------------------------------------------------- */ |
| 236 | } |
| 237 | /* unknown encoding type, just dump as-is */ |
| 238 | else goto NO_DECODING; |
| 239 | } |
| 240 | |
| 241 | |
| 242 | FILE *mime_get_decode_file(uschar *pname, uschar *fname) { |
| 243 | FILE *f = NULL; |
| 244 | uschar *filename; |
| 245 | |
| 246 | filename = (uschar *)malloc(2048); |
| 247 | |
| 248 | if ((pname != NULL) && (fname != NULL)) { |
| 249 | snprintf(CS filename, 2048, "%s/%s", pname, fname); |
| 250 | f = fopen(CS filename,"w+"); |
| 251 | } |
| 252 | else if (pname == NULL) { |
| 253 | f = fopen(CS fname,"w+"); |
| 254 | } |
| 255 | else if (fname == NULL) { |
| 256 | int file_nr = 0; |
| 257 | int result = 0; |
| 258 | |
| 259 | /* must find first free sequential filename */ |
| 260 | do { |
| 261 | struct stat mystat; |
| 262 | snprintf(CS filename,2048,"%s/%s-%05u", pname, message_id, file_nr); |
| 263 | file_nr++; |
| 264 | /* security break */ |
| 265 | if (file_nr >= 1024) |
| 266 | break; |
| 267 | result = stat(CS filename,&mystat); |
| 268 | } |
| 269 | while(result != -1); |
| 270 | f = fopen(CS filename,"w+"); |
| 271 | }; |
| 272 | |
| 273 | /* set expansion variable */ |
| 274 | mime_decoded_filename = filename; |
| 275 | |
| 276 | return f; |
| 277 | } |
| 278 | |
| 279 | |
| 280 | int mime_decode(uschar **listptr) { |
| 281 | int sep = 0; |
| 282 | uschar *list = *listptr; |
| 283 | uschar *option; |
| 284 | uschar option_buffer[1024]; |
| 285 | uschar decode_path[1024]; |
| 286 | FILE *decode_file = NULL; |
| 287 | uschar *buffer = NULL; |
| 288 | long f_pos = 0; |
| 289 | unsigned int size_counter = 0; |
| 290 | |
| 291 | if (mime_stream == NULL) |
| 292 | return FAIL; |
| 293 | |
| 294 | f_pos = ftell(mime_stream); |
| 295 | |
| 296 | /* build default decode path (will exist since MBOX must be spooled up) */ |
| 297 | snprintf(CS decode_path,1024,"%s/scan/%s",spool_directory,message_id); |
| 298 | |
| 299 | /* reserve a line buffer to work in */ |
| 300 | buffer = (uschar *)malloc(MIME_MAX_LINE_LENGTH+1); |
| 301 | if (buffer == NULL) { |
| 302 | log_write(0, LOG_PANIC, |
| 303 | "decode ACL condition: can't allocate %d bytes of memory.", MIME_MAX_LINE_LENGTH+1); |
| 304 | return DEFER; |
| 305 | }; |
| 306 | |
| 307 | /* try to find 1st option */ |
| 308 | if ((option = string_nextinlist(&list, &sep, |
| 309 | option_buffer, |
| 310 | sizeof(option_buffer))) != NULL) { |
| 311 | |
| 312 | /* parse 1st option */ |
| 313 | if ( (Ustrcmp(option,"false") == 0) || (Ustrcmp(option,"0") == 0) ) { |
| 314 | /* explicitly no decoding */ |
| 315 | return FAIL; |
| 316 | }; |
| 317 | |
| 318 | if (Ustrcmp(option,"default") == 0) { |
| 319 | /* explicit default path + file names */ |
| 320 | goto DEFAULT_PATH; |
| 321 | }; |
| 322 | |
| 323 | if (option[0] == '/') { |
| 324 | struct stat statbuf; |
| 325 | |
| 326 | memset(&statbuf,0,sizeof(statbuf)); |
| 327 | |
| 328 | /* assume either path or path+file name */ |
| 329 | if ( (stat(CS option, &statbuf) == 0) && S_ISDIR(statbuf.st_mode) ) |
| 330 | /* is directory, use it as decode_path */ |
| 331 | decode_file = mime_get_decode_file(option, NULL); |
| 332 | else |
| 333 | /* does not exist or is a file, use as full file name */ |
| 334 | decode_file = mime_get_decode_file(NULL, option); |
| 335 | } |
| 336 | else |
| 337 | /* assume file name only, use default path */ |
| 338 | decode_file = mime_get_decode_file(decode_path, option); |
| 339 | } |
| 340 | else |
| 341 | /* no option? patch default path */ |
| 342 | DEFAULT_PATH: decode_file = mime_get_decode_file(decode_path, NULL); |
| 343 | |
| 344 | if (decode_file == NULL) |
| 345 | return DEFER; |
| 346 | |
| 347 | /* read data linewise and dump it to the file, |
| 348 | while looking for the current boundary */ |
| 349 | while(fgets(CS buffer, MIME_MAX_LINE_LENGTH, mime_stream) != NULL) { |
| 350 | uschar *decoded_line = NULL; |
| 351 | int decoded_line_length = 0; |
| 352 | |
| 353 | if (mime_current_boundary != NULL) { |
| 354 | /* boundary line must start with 2 dashes */ |
| 355 | if (Ustrncmp(buffer,"--",2) == 0) { |
| 356 | if (Ustrncmp((buffer+2),mime_current_boundary,Ustrlen(mime_current_boundary)) == 0) |
| 357 | break; |
| 358 | }; |
| 359 | }; |
| 360 | |
| 361 | decoded_line = mime_parse_line(buffer, mime_content_transfer_encoding, &decoded_line_length); |
| 362 | /* write line to decode file */ |
| 363 | if (fwrite(decoded_line, 1, decoded_line_length, decode_file) < decoded_line_length) { |
| 364 | /* error/short write */ |
| 365 | clearerr(mime_stream); |
| 366 | fseek(mime_stream,f_pos,SEEK_SET); |
| 367 | return DEFER; |
| 368 | }; |
| 369 | size_counter += decoded_line_length; |
| 370 | |
| 371 | if (size_counter > 1023) { |
| 372 | if ((mime_content_size + (size_counter / 1024)) < 65535) |
| 373 | mime_content_size += (size_counter / 1024); |
| 374 | else |
| 375 | mime_content_size = 65535; |
| 376 | size_counter = (size_counter % 1024); |
| 377 | }; |
| 378 | |
| 379 | free(decoded_line); |
| 380 | } |
| 381 | |
| 382 | fclose(decode_file); |
| 383 | |
| 384 | clearerr(mime_stream); |
| 385 | fseek(mime_stream,f_pos,SEEK_SET); |
| 386 | |
| 387 | /* round up remaining size bytes to one k */ |
| 388 | if (size_counter) { |
| 389 | mime_content_size++; |
| 390 | }; |
| 391 | |
| 392 | return OK; |
| 393 | } |
| 394 | |
| 395 | int mime_get_header(FILE *f, uschar *header) { |
| 396 | int c = EOF; |
| 397 | int done = 0; |
| 398 | int header_value_mode = 0; |
| 399 | int header_open_brackets = 0; |
| 400 | int num_copied = 0; |
| 401 | |
| 402 | while(!done) { |
| 403 | |
| 404 | c = fgetc(f); |
| 405 | if (c == EOF) break; |
| 406 | |
| 407 | /* always skip CRs */ |
| 408 | if (c == '\r') continue; |
| 409 | |
| 410 | if (c == '\n') { |
| 411 | if (num_copied > 0) { |
| 412 | /* look if next char is '\t' or ' ' */ |
| 413 | c = fgetc(f); |
| 414 | if (c == EOF) break; |
| 415 | if ( (c == '\t') || (c == ' ') ) continue; |
| 416 | ungetc(c,f); |
| 417 | }; |
| 418 | /* end of the header, terminate with ';' */ |
| 419 | c = ';'; |
| 420 | done = 1; |
| 421 | }; |
| 422 | |
| 423 | /* skip control characters */ |
| 424 | if (c < 32) continue; |
| 425 | |
| 426 | if (header_value_mode) { |
| 427 | /* --------- value mode ----------- */ |
| 428 | /* skip leading whitespace */ |
| 429 | if ( ((c == '\t') || (c == ' ')) && (header_value_mode == 1) ) |
| 430 | continue; |
| 431 | |
| 432 | /* we have hit a non-whitespace char, start copying value data */ |
| 433 | header_value_mode = 2; |
| 434 | |
| 435 | /* skip quotes */ |
| 436 | if (c == '"') continue; |
| 437 | |
| 438 | /* leave value mode on ';' */ |
| 439 | if (c == ';') { |
| 440 | header_value_mode = 0; |
| 441 | }; |
| 442 | /* -------------------------------- */ |
| 443 | } |
| 444 | else { |
| 445 | /* -------- non-value mode -------- */ |
| 446 | /* skip whitespace + tabs */ |
| 447 | if ( (c == ' ') || (c == '\t') ) |
| 448 | continue; |
| 449 | if (c == '\\') { |
| 450 | /* quote next char. can be used |
| 451 | to escape brackets. */ |
| 452 | c = fgetc(f); |
| 453 | if (c == EOF) break; |
| 454 | } |
| 455 | else if (c == '(') { |
| 456 | header_open_brackets++; |
| 457 | continue; |
| 458 | } |
| 459 | else if ((c == ')') && header_open_brackets) { |
| 460 | header_open_brackets--; |
| 461 | continue; |
| 462 | } |
| 463 | else if ( (c == '=') && !header_open_brackets ) { |
| 464 | /* enter value mode */ |
| 465 | header_value_mode = 1; |
| 466 | }; |
| 467 | |
| 468 | /* skip chars while we are in a comment */ |
| 469 | if (header_open_brackets > 0) |
| 470 | continue; |
| 471 | /* -------------------------------- */ |
| 472 | }; |
| 473 | |
| 474 | /* copy the char to the buffer */ |
| 475 | header[num_copied] = (uschar)c; |
| 476 | /* raise counter */ |
| 477 | num_copied++; |
| 478 | |
| 479 | /* break if header buffer is full */ |
| 480 | if (num_copied > MIME_MAX_HEADER_SIZE-1) { |
| 481 | done = 1; |
| 482 | }; |
| 483 | }; |
| 484 | |
| 485 | if (header[num_copied-1] != ';') { |
| 486 | header[num_copied-1] = ';'; |
| 487 | }; |
| 488 | |
| 489 | /* 0-terminate */ |
| 490 | header[num_copied] = '\0'; |
| 491 | |
| 492 | /* return 0 for EOF or empty line */ |
| 493 | if ((c == EOF) || (num_copied == 1)) |
| 494 | return 0; |
| 495 | else |
| 496 | return 1; |
| 497 | } |
| 498 | |
| 499 | |
| 500 | int mime_acl_check(FILE *f, struct mime_boundary_context *context, uschar |
| 501 | **user_msgptr, uschar **log_msgptr) { |
| 502 | int rc = OK; |
| 503 | uschar *header = NULL; |
| 504 | struct mime_boundary_context nested_context; |
| 505 | |
| 506 | /* reserve a line buffer to work in */ |
| 507 | header = (uschar *)malloc(MIME_MAX_HEADER_SIZE+1); |
| 508 | if (header == NULL) { |
| 509 | log_write(0, LOG_PANIC, |
| 510 | "acl_smtp_mime: can't allocate %d bytes of memory.", MIME_MAX_HEADER_SIZE+1); |
| 511 | return DEFER; |
| 512 | }; |
| 513 | |
| 514 | /* Not actually used at the moment, but will be vital to fixing |
| 515 | * some RFC 2046 nonconformance later... */ |
| 516 | nested_context.parent = context; |
| 517 | |
| 518 | /* loop through parts */ |
| 519 | while(1) { |
| 520 | |
| 521 | /* reset all per-part mime variables */ |
| 522 | mime_anomaly_level = 0; |
| 523 | mime_anomaly_text = NULL; |
| 524 | mime_boundary = NULL; |
| 525 | mime_charset = NULL; |
| 526 | mime_decoded_filename = NULL; |
| 527 | mime_filename = NULL; |
| 528 | mime_content_description = NULL; |
| 529 | mime_content_disposition = NULL; |
| 530 | mime_content_id = NULL; |
| 531 | mime_content_transfer_encoding = NULL; |
| 532 | mime_content_type = NULL; |
| 533 | mime_is_multipart = 0; |
| 534 | mime_content_size = 0; |
| 535 | |
| 536 | /* |
| 537 | If boundary is null, we assume that *f is positioned on the start of headers (for example, |
| 538 | at the very beginning of a message. |
| 539 | If a boundary is given, we must first advance to it to reach the start of the next header |
| 540 | block. |
| 541 | */ |
| 542 | |
| 543 | /* NOTE -- there's an error here -- RFC2046 specifically says to |
| 544 | * check for outer boundaries. This code doesn't do that, and |
| 545 | * I haven't fixed this. |
| 546 | * |
| 547 | * (I have moved partway towards adding support, however, by adding |
| 548 | * a "parent" field to my new boundary-context structure.) |
| 549 | */ |
| 550 | if (context != NULL) { |
| 551 | while(fgets(CS header, MIME_MAX_HEADER_SIZE, f) != NULL) { |
| 552 | /* boundary line must start with 2 dashes */ |
| 553 | if (Ustrncmp(header,"--",2) == 0) { |
| 554 | if (Ustrncmp((header+2),context->boundary,Ustrlen(context->boundary)) == 0) { |
| 555 | /* found boundary */ |
| 556 | if (Ustrncmp((header+2+Ustrlen(context->boundary)),"--",2) == 0) { |
| 557 | /* END boundary found */ |
| 558 | debug_printf("End boundary found %s\n", context->boundary); |
| 559 | return rc; |
| 560 | } |
| 561 | else { |
| 562 | debug_printf("Next part with boundary %s\n", context->boundary); |
| 563 | }; |
| 564 | /* can't use break here */ |
| 565 | goto DECODE_HEADERS; |
| 566 | } |
| 567 | }; |
| 568 | } |
| 569 | /* Hit EOF or read error. Ugh. */ |
| 570 | debug_printf("Hit EOF ...\n"); |
| 571 | return rc; |
| 572 | }; |
| 573 | |
| 574 | DECODE_HEADERS: |
| 575 | /* parse headers, set up expansion variables */ |
| 576 | while(mime_get_header(f,header)) { |
| 577 | int i; |
| 578 | /* loop through header list */ |
| 579 | for (i = 0; i < mime_header_list_size; i++) { |
| 580 | uschar *header_value = NULL; |
| 581 | int header_value_len = 0; |
| 582 | |
| 583 | /* found an interesting header? */ |
| 584 | if (strncmpic(mime_header_list[i].name,header,mime_header_list[i].namelen) == 0) { |
| 585 | uschar *p = header + mime_header_list[i].namelen; |
| 586 | /* yes, grab the value (normalize to lower case) |
| 587 | and copy to its corresponding expansion variable */ |
| 588 | while(*p != ';') { |
| 589 | *p = tolower(*p); |
| 590 | p++; |
| 591 | }; |
| 592 | header_value_len = (p - (header + mime_header_list[i].namelen)); |
| 593 | header_value = (uschar *)malloc(header_value_len+1); |
| 594 | memset(header_value,0,header_value_len+1); |
| 595 | p = header + mime_header_list[i].namelen; |
| 596 | Ustrncpy(header_value, p, header_value_len); |
| 597 | debug_printf("Found %s MIME header, value is '%s'\n", mime_header_list[i].name, header_value); |
| 598 | *((uschar **)(mime_header_list[i].value)) = header_value; |
| 599 | |
| 600 | /* make p point to the next character after the closing ';' */ |
| 601 | p += (header_value_len+1); |
| 602 | |
| 603 | /* grab all param=value tags on the remaining line, check if they are interesting */ |
| 604 | NEXT_PARAM_SEARCH: while (*p != 0) { |
| 605 | int j; |
| 606 | for (j = 0; j < mime_parameter_list_size; j++) { |
| 607 | uschar *param_value = NULL; |
| 608 | int param_value_len = 0; |
| 609 | |
| 610 | /* found an interesting parameter? */ |
| 611 | if (strncmpic(mime_parameter_list[j].name,p,mime_parameter_list[j].namelen) == 0) { |
| 612 | uschar *q = p + mime_parameter_list[j].namelen; |
| 613 | /* yes, grab the value and copy to its corresponding expansion variable */ |
| 614 | while(*q != ';') q++; |
| 615 | param_value_len = (q - (p + mime_parameter_list[j].namelen)); |
| 616 | param_value = (uschar *)malloc(param_value_len+1); |
| 617 | memset(param_value,0,param_value_len+1); |
| 618 | q = p + mime_parameter_list[j].namelen; |
| 619 | Ustrncpy(param_value, q, param_value_len); |
| 620 | param_value = rfc2047_decode(param_value, TRUE, NULL, 32, ¶m_value_len, &q); |
| 621 | debug_printf("Found %s MIME parameter in %s header, value is '%s'\n", mime_parameter_list[j].name, mime_header_list[i].name, param_value); |
| 622 | *((uschar **)(mime_parameter_list[j].value)) = param_value; |
| 623 | p += (mime_parameter_list[j].namelen + param_value_len + 1); |
| 624 | goto NEXT_PARAM_SEARCH; |
| 625 | }; |
| 626 | } |
| 627 | /* There is something, but not one of our interesting parameters. |
| 628 | Advance to the next semicolon */ |
| 629 | while(*p != ';') p++; |
| 630 | p++; |
| 631 | }; |
| 632 | }; |
| 633 | }; |
| 634 | }; |
| 635 | |
| 636 | /* set additional flag variables (easier access) */ |
| 637 | if ( (mime_content_type != NULL) && |
| 638 | (Ustrncmp(mime_content_type,"multipart",9) == 0) ) |
| 639 | mime_is_multipart = 1; |
| 640 | |
| 641 | /* Make a copy of the boundary pointer. |
| 642 | Required since mime_boundary is global |
| 643 | and can be overwritten further down in recursion */ |
| 644 | nested_context.boundary = mime_boundary; |
| 645 | |
| 646 | /* raise global counter */ |
| 647 | mime_part_count++; |
| 648 | |
| 649 | /* copy current file handle to global variable */ |
| 650 | mime_stream = f; |
| 651 | mime_current_boundary = context ? context->boundary : 0; |
| 652 | |
| 653 | /* Note the context */ |
| 654 | mime_is_coverletter = !(context && context->context == MBC_ATTACHMENT); |
| 655 | |
| 656 | /* call ACL handling function */ |
| 657 | rc = acl_check(ACL_WHERE_MIME, NULL, acl_smtp_mime, user_msgptr, log_msgptr); |
| 658 | |
| 659 | mime_stream = NULL; |
| 660 | mime_current_boundary = NULL; |
| 661 | |
| 662 | if (rc != OK) break; |
| 663 | |
| 664 | /* If we have a multipart entity and a boundary, go recursive */ |
| 665 | if ( (mime_content_type != NULL) && |
| 666 | (nested_context.boundary != NULL) && |
| 667 | (Ustrncmp(mime_content_type,"multipart",9) == 0) ) { |
| 668 | debug_printf("Entering multipart recursion, boundary '%s'\n", nested_context.boundary); |
| 669 | |
| 670 | if (context && context->context == MBC_ATTACHMENT) |
| 671 | nested_context.context = MBC_ATTACHMENT; |
| 672 | else if (!Ustrcmp(mime_content_type,"multipart/alternative") |
| 673 | || !Ustrcmp(mime_content_type,"multipart/related")) |
| 674 | nested_context.context = MBC_COVERLETTER_ALL; |
| 675 | else |
| 676 | nested_context.context = MBC_COVERLETTER_ONESHOT; |
| 677 | |
| 678 | rc = mime_acl_check(f, &nested_context, user_msgptr, log_msgptr); |
| 679 | if (rc != OK) break; |
| 680 | } |
| 681 | else if ( (mime_content_type != NULL) && |
| 682 | (Ustrncmp(mime_content_type,"message/rfc822",14) == 0) ) { |
| 683 | uschar *rfc822name = NULL; |
| 684 | uschar filename[2048]; |
| 685 | int file_nr = 0; |
| 686 | int result = 0; |
| 687 | |
| 688 | /* must find first free sequential filename */ |
| 689 | do { |
| 690 | struct stat mystat; |
| 691 | snprintf(CS filename,2048,"%s/scan/%s/__rfc822_%05u", spool_directory, message_id, file_nr); |
| 692 | file_nr++; |
| 693 | /* security break */ |
| 694 | if (file_nr >= 128) |
| 695 | goto NO_RFC822; |
| 696 | result = stat(CS filename,&mystat); |
| 697 | } |
| 698 | while(result != -1); |
| 699 | |
| 700 | rfc822name = filename; |
| 701 | |
| 702 | /* decode RFC822 attachment */ |
| 703 | mime_decoded_filename = NULL; |
| 704 | mime_stream = f; |
| 705 | mime_current_boundary = context ? context->boundary : NULL; |
| 706 | mime_decode(&rfc822name); |
| 707 | mime_stream = NULL; |
| 708 | mime_current_boundary = NULL; |
| 709 | if (mime_decoded_filename == NULL) { |
| 710 | /* decoding failed */ |
| 711 | log_write(0, LOG_MAIN, |
| 712 | "mime_regex acl condition warning - could not decode RFC822 MIME part to file."); |
| 713 | return DEFER; |
| 714 | }; |
| 715 | mime_decoded_filename = NULL; |
| 716 | }; |
| 717 | |
| 718 | NO_RFC822: |
| 719 | /* If the boundary of this instance is NULL, we are finished here */ |
| 720 | if (context == NULL) break; |
| 721 | |
| 722 | if (context->context == MBC_COVERLETTER_ONESHOT) |
| 723 | context->context = MBC_ATTACHMENT; |
| 724 | |
| 725 | }; |
| 726 | |
| 727 | return rc; |
| 728 | } |
| 729 | |
| 730 | #endif |