| 1 | /* |
| 2 | * PDKIM - a RFC4871 (DKIM) implementation |
| 3 | * |
| 4 | * Copyright (C) 2009 - 2016 Tom Kistner <tom@duncanthrax.net> |
| 5 | * Copyright (C) 2016 Jeremy Harris <jgh@exim.org> |
| 6 | * |
| 7 | * http://duncanthrax.net/pdkim/ |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License as published by |
| 11 | * the Free Software Foundation; either version 2 of the License, or |
| 12 | * (at your option) any later version. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License along |
| 20 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 21 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 22 | */ |
| 23 | |
| 24 | #include "../exim.h" |
| 25 | |
| 26 | |
| 27 | #ifndef DISABLE_DKIM /* entire file */ |
| 28 | |
| 29 | #ifndef SUPPORT_TLS |
| 30 | # error Need SUPPORT_TLS for DKIM |
| 31 | #endif |
| 32 | |
| 33 | #include "crypt_ver.h" |
| 34 | |
| 35 | #ifdef RSA_OPENSSL |
| 36 | # include <openssl/rsa.h> |
| 37 | # include <openssl/ssl.h> |
| 38 | # include <openssl/err.h> |
| 39 | #elif defined(RSA_GNUTLS) |
| 40 | # include <gnutls/gnutls.h> |
| 41 | # include <gnutls/x509.h> |
| 42 | # include <gnutls/abstract.h> |
| 43 | #endif |
| 44 | |
| 45 | #ifdef SHA_GNUTLS |
| 46 | # include <gnutls/crypto.h> |
| 47 | #elif defined(SHA_POLARSSL) |
| 48 | # include "polarssl/sha1.h" |
| 49 | # include "polarssl/sha2.h" |
| 50 | #endif |
| 51 | |
| 52 | #include "pdkim.h" |
| 53 | |
| 54 | #define PDKIM_SIGNATURE_VERSION "1" |
| 55 | #define PDKIM_PUB_RECORD_VERSION "DKIM1" |
| 56 | |
| 57 | #define PDKIM_MAX_HEADER_LEN 65536 |
| 58 | #define PDKIM_MAX_HEADERS 512 |
| 59 | #define PDKIM_MAX_BODY_LINE_LEN 16384 |
| 60 | #define PDKIM_DNS_TXT_MAX_NAMELEN 1024 |
| 61 | #define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\ |
| 62 | "Message-ID:To:Cc:MIME-Version:Content-Type:"\ |
| 63 | "Content-Transfer-Encoding:Content-ID:"\ |
| 64 | "Content-Description:Resent-Date:Resent-From:"\ |
| 65 | "Resent-Sender:Resent-To:Resent-Cc:"\ |
| 66 | "Resent-Message-ID:In-Reply-To:References:"\ |
| 67 | "List-Id:List-Help:List-Unsubscribe:"\ |
| 68 | "List-Subscribe:List-Post:List-Owner:List-Archive" |
| 69 | |
| 70 | /* -------------------------------------------------------------------------- */ |
| 71 | struct pdkim_stringlist { |
| 72 | char *value; |
| 73 | int tag; |
| 74 | void *next; |
| 75 | }; |
| 76 | |
| 77 | #define PDKIM_STR_ALLOC_FRAG 256 |
| 78 | struct pdkim_str { |
| 79 | char *str; |
| 80 | unsigned int len; |
| 81 | unsigned int allocated; |
| 82 | }; |
| 83 | |
| 84 | /* -------------------------------------------------------------------------- */ |
| 85 | /* A bunch of list constants */ |
| 86 | const char *pdkim_querymethods[] = { |
| 87 | "dns/txt", |
| 88 | NULL |
| 89 | }; |
| 90 | const char *pdkim_algos[] = { |
| 91 | "rsa-sha256", |
| 92 | "rsa-sha1", |
| 93 | NULL |
| 94 | }; |
| 95 | const char *pdkim_canons[] = { |
| 96 | "simple", |
| 97 | "relaxed", |
| 98 | NULL |
| 99 | }; |
| 100 | const char *pdkim_hashes[] = { |
| 101 | "sha256", |
| 102 | "sha1", |
| 103 | NULL |
| 104 | }; |
| 105 | const char *pdkim_keytypes[] = { |
| 106 | "rsa", |
| 107 | NULL |
| 108 | }; |
| 109 | |
| 110 | typedef struct pdkim_combined_canon_entry { |
| 111 | const char *str; |
| 112 | int canon_headers; |
| 113 | int canon_body; |
| 114 | } pdkim_combined_canon_entry; |
| 115 | |
| 116 | pdkim_combined_canon_entry pdkim_combined_canons[] = { |
| 117 | { "simple/simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE }, |
| 118 | { "simple/relaxed", PDKIM_CANON_SIMPLE, PDKIM_CANON_RELAXED }, |
| 119 | { "relaxed/simple", PDKIM_CANON_RELAXED, PDKIM_CANON_SIMPLE }, |
| 120 | { "relaxed/relaxed", PDKIM_CANON_RELAXED, PDKIM_CANON_RELAXED }, |
| 121 | { "simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE }, |
| 122 | { "relaxed", PDKIM_CANON_RELAXED, PDKIM_CANON_SIMPLE }, |
| 123 | { NULL, 0, 0 } |
| 124 | }; |
| 125 | |
| 126 | |
| 127 | /* -------------------------------------------------------------------------- */ |
| 128 | |
| 129 | const char * |
| 130 | pdkim_verify_status_str(int status) |
| 131 | { |
| 132 | switch(status) { |
| 133 | case PDKIM_VERIFY_NONE: return "PDKIM_VERIFY_NONE"; |
| 134 | case PDKIM_VERIFY_INVALID: return "PDKIM_VERIFY_INVALID"; |
| 135 | case PDKIM_VERIFY_FAIL: return "PDKIM_VERIFY_FAIL"; |
| 136 | case PDKIM_VERIFY_PASS: return "PDKIM_VERIFY_PASS"; |
| 137 | default: return "PDKIM_VERIFY_UNKNOWN"; |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | const char * |
| 142 | pdkim_verify_ext_status_str(int ext_status) |
| 143 | { |
| 144 | switch(ext_status) { |
| 145 | case PDKIM_VERIFY_FAIL_BODY: return "PDKIM_VERIFY_FAIL_BODY"; |
| 146 | case PDKIM_VERIFY_FAIL_MESSAGE: return "PDKIM_VERIFY_FAIL_MESSAGE"; |
| 147 | case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE: return "PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE"; |
| 148 | case PDKIM_VERIFY_INVALID_BUFFER_SIZE: return "PDKIM_VERIFY_INVALID_BUFFER_SIZE"; |
| 149 | case PDKIM_VERIFY_INVALID_PUBKEY_PARSING: return "PDKIM_VERIFY_INVALID_PUBKEY_PARSING"; |
| 150 | default: return "PDKIM_VERIFY_UNKNOWN"; |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | |
| 155 | /* -------------------------------------------------------------------------- */ |
| 156 | /* Print debugging functions */ |
| 157 | void |
| 158 | pdkim_quoteprint(const char *data, int len, int lf) |
| 159 | { |
| 160 | int i; |
| 161 | const unsigned char *p = (const unsigned char *)data; |
| 162 | |
| 163 | for (i = 0; i < len; i++) |
| 164 | { |
| 165 | const int c = p[i]; |
| 166 | switch (c) |
| 167 | { |
| 168 | case ' ' : debug_printf("{SP}"); break; |
| 169 | case '\t': debug_printf("{TB}"); break; |
| 170 | case '\r': debug_printf("{CR}"); break; |
| 171 | case '\n': debug_printf("{LF}"); break; |
| 172 | case '{' : debug_printf("{BO}"); break; |
| 173 | case '}' : debug_printf("{BC}"); break; |
| 174 | default: |
| 175 | if ( (c < 32) || (c > 127) ) |
| 176 | debug_printf("{%02x}", c); |
| 177 | else |
| 178 | debug_printf("%c", c); |
| 179 | break; |
| 180 | } |
| 181 | } |
| 182 | if (lf) |
| 183 | debug_printf("\n"); |
| 184 | } |
| 185 | |
| 186 | void |
| 187 | pdkim_hexprint(const char *data, int len, int lf) |
| 188 | { |
| 189 | int i; |
| 190 | const unsigned char *p = (const unsigned char *)data; |
| 191 | |
| 192 | for (i = 0 ; i < len; i++) |
| 193 | debug_printf("%02x", p[i]); |
| 194 | if (lf) |
| 195 | debug_printf("\n"); |
| 196 | } |
| 197 | |
| 198 | |
| 199 | |
| 200 | /* String package: should be replaced by Exim standard ones */ |
| 201 | |
| 202 | static pdkim_stringlist * |
| 203 | pdkim_prepend_stringlist(pdkim_stringlist *base, char *str) |
| 204 | { |
| 205 | pdkim_stringlist *new_entry = malloc(sizeof(pdkim_stringlist)); |
| 206 | |
| 207 | if (!new_entry) return NULL; |
| 208 | memset(new_entry, 0, sizeof(pdkim_stringlist)); |
| 209 | if (!(new_entry->value = strdup(str))) return NULL; |
| 210 | if (base) |
| 211 | { |
| 212 | pdkim_stringlist *last = base; |
| 213 | while (last->next != NULL) { last = last->next; } |
| 214 | last->next = new_entry; |
| 215 | return base; |
| 216 | } |
| 217 | else |
| 218 | return new_entry; |
| 219 | } |
| 220 | |
| 221 | |
| 222 | /* -------------------------------------------------------------------------- */ |
| 223 | /* A small "growing string" implementation to escape malloc/realloc hell */ |
| 224 | |
| 225 | static pdkim_str * |
| 226 | pdkim_strnew (const char *cstr) |
| 227 | { |
| 228 | unsigned int len = cstr ? strlen(cstr) : 0; |
| 229 | pdkim_str *p = malloc(sizeof(pdkim_str)); |
| 230 | |
| 231 | if (!p) return NULL; |
| 232 | memset(p, 0, sizeof(pdkim_str)); |
| 233 | if (!(p->str = malloc(len+1))) |
| 234 | { |
| 235 | free(p); |
| 236 | return NULL; |
| 237 | } |
| 238 | p->allocated = len+1; |
| 239 | p->len = len; |
| 240 | if (cstr) |
| 241 | strcpy(p->str, cstr); |
| 242 | else |
| 243 | p->str[p->len] = '\0'; |
| 244 | return p; |
| 245 | } |
| 246 | |
| 247 | static char * |
| 248 | pdkim_strncat(pdkim_str *str, const char *data, int len) |
| 249 | { |
| 250 | if ((str->allocated - str->len) < (len+1)) |
| 251 | { |
| 252 | /* Extend the buffer */ |
| 253 | int num_frags = ((len+1)/PDKIM_STR_ALLOC_FRAG)+1; |
| 254 | char *n = realloc(str->str, |
| 255 | (str->allocated+(num_frags*PDKIM_STR_ALLOC_FRAG))); |
| 256 | if (n == NULL) return NULL; |
| 257 | str->str = n; |
| 258 | str->allocated += (num_frags*PDKIM_STR_ALLOC_FRAG); |
| 259 | } |
| 260 | strncpy(&(str->str[str->len]), data, len); |
| 261 | str->len += len; |
| 262 | str->str[str->len] = '\0'; |
| 263 | return str->str; |
| 264 | } |
| 265 | |
| 266 | static char * |
| 267 | pdkim_strcat(pdkim_str *str, const char *cstr) |
| 268 | { |
| 269 | return pdkim_strncat(str, cstr, strlen(cstr)); |
| 270 | } |
| 271 | |
| 272 | static char * |
| 273 | pdkim_strtrim(pdkim_str *str) |
| 274 | { |
| 275 | char *p = str->str; |
| 276 | char *q = str->str; |
| 277 | while ( (*p != '\0') && ((*p == '\t') || (*p == ' ')) ) p++; |
| 278 | while (*p != '\0') {*q = *p; q++; p++;} |
| 279 | *q = '\0'; |
| 280 | while ( (q != str->str) && ( (*q == '\0') || (*q == '\t') || (*q == ' ') ) ) |
| 281 | { |
| 282 | *q = '\0'; |
| 283 | q--; |
| 284 | } |
| 285 | str->len = strlen(str->str); |
| 286 | return str->str; |
| 287 | } |
| 288 | |
| 289 | static char * |
| 290 | pdkim_strclear(pdkim_str *str) |
| 291 | { |
| 292 | str->str[0] = '\0'; |
| 293 | str->len = 0; |
| 294 | return str->str; |
| 295 | } |
| 296 | |
| 297 | static void |
| 298 | pdkim_strfree(pdkim_str *str) |
| 299 | { |
| 300 | if (!str) return; |
| 301 | if (str->str) free(str->str); |
| 302 | free(str); |
| 303 | } |
| 304 | |
| 305 | |
| 306 | |
| 307 | /* -------------------------------------------------------------------------- */ |
| 308 | |
| 309 | static void |
| 310 | pdkim_free_pubkey(pdkim_pubkey *pub) |
| 311 | { |
| 312 | if (pub) |
| 313 | { |
| 314 | if (pub->version ) free(pub->version); |
| 315 | if (pub->granularity) free(pub->granularity); |
| 316 | if (pub->hashes ) free(pub->hashes); |
| 317 | if (pub->keytype ) free(pub->keytype); |
| 318 | if (pub->srvtype ) free(pub->srvtype); |
| 319 | if (pub->notes ) free(pub->notes); |
| 320 | /* if (pub->key ) free(pub->key); */ |
| 321 | free(pub); |
| 322 | } |
| 323 | } |
| 324 | |
| 325 | |
| 326 | /* -------------------------------------------------------------------------- */ |
| 327 | |
| 328 | static void |
| 329 | pdkim_free_sig(pdkim_signature *sig) |
| 330 | { |
| 331 | if (sig) |
| 332 | { |
| 333 | pdkim_signature *next = (pdkim_signature *)sig->next; |
| 334 | |
| 335 | pdkim_stringlist *e = sig->headers; |
| 336 | while(e) |
| 337 | { |
| 338 | pdkim_stringlist *c = e; |
| 339 | if (e->value) free(e->value); |
| 340 | e = e->next; |
| 341 | free(c); |
| 342 | } |
| 343 | |
| 344 | if (sig->selector ) free(sig->selector); |
| 345 | if (sig->domain ) free(sig->domain); |
| 346 | if (sig->identity ) free(sig->identity); |
| 347 | if (sig->headernames ) free(sig->headernames); |
| 348 | if (sig->copiedheaders ) free(sig->copiedheaders); |
| 349 | if (sig->rsa_privkey ) free(sig->rsa_privkey); |
| 350 | if (sig->sign_headers ) free(sig->sign_headers); |
| 351 | if (sig->signature_header) free(sig->signature_header); |
| 352 | |
| 353 | if (sig->pubkey) pdkim_free_pubkey(sig->pubkey); |
| 354 | |
| 355 | free(sig); |
| 356 | if (next) pdkim_free_sig(next); |
| 357 | } |
| 358 | } |
| 359 | |
| 360 | |
| 361 | /* -------------------------------------------------------------------------- */ |
| 362 | |
| 363 | DLLEXPORT void |
| 364 | pdkim_free_ctx(pdkim_ctx *ctx) |
| 365 | { |
| 366 | if (ctx) |
| 367 | { |
| 368 | pdkim_stringlist *e = ctx->headers; |
| 369 | while(e) |
| 370 | { |
| 371 | pdkim_stringlist *c = e; |
| 372 | if (e->value) free(e->value); |
| 373 | e = e->next; |
| 374 | free(c); |
| 375 | } |
| 376 | pdkim_free_sig(ctx->sig); |
| 377 | pdkim_strfree(ctx->cur_header); |
| 378 | free(ctx); |
| 379 | } |
| 380 | } |
| 381 | |
| 382 | |
| 383 | /* -------------------------------------------------------------------------- */ |
| 384 | /* Matches the name of the passed raw "header" against |
| 385 | the passed colon-separated "list", starting at entry |
| 386 | "start". Returns the position of the header name in |
| 387 | the list. */ |
| 388 | |
| 389 | static int |
| 390 | header_name_match(const char *header, |
| 391 | char *tick, |
| 392 | int do_tick) |
| 393 | { |
| 394 | char *hname; |
| 395 | char *lcopy; |
| 396 | char *p; |
| 397 | char *q; |
| 398 | int rc = PDKIM_FAIL; |
| 399 | |
| 400 | /* Get header name */ |
| 401 | char *hcolon = strchr(header, ':'); |
| 402 | |
| 403 | if (!hcolon) return rc; /* This isn't a header */ |
| 404 | |
| 405 | if (!(hname = malloc((hcolon-header)+1))) |
| 406 | return PDKIM_ERR_OOM; |
| 407 | memset(hname, 0, (hcolon-header)+1); |
| 408 | strncpy(hname, header, (hcolon-header)); |
| 409 | |
| 410 | /* Copy tick-off list locally, so we can punch zeroes into it */ |
| 411 | if (!(lcopy = strdup(tick))) |
| 412 | { |
| 413 | free(hname); |
| 414 | return PDKIM_ERR_OOM; |
| 415 | } |
| 416 | p = lcopy; |
| 417 | q = strchr(p, ':'); |
| 418 | while (q) |
| 419 | { |
| 420 | *q = '\0'; |
| 421 | |
| 422 | if (strcasecmp(p, hname) == 0) |
| 423 | { |
| 424 | rc = PDKIM_OK; |
| 425 | /* Invalidate header name instance in tick-off list */ |
| 426 | if (do_tick) tick[p-lcopy] = '_'; |
| 427 | goto BAIL; |
| 428 | } |
| 429 | |
| 430 | p = q+1; |
| 431 | q = strchr(p, ':'); |
| 432 | } |
| 433 | |
| 434 | if (strcasecmp(p, hname) == 0) |
| 435 | { |
| 436 | rc = PDKIM_OK; |
| 437 | /* Invalidate header name instance in tick-off list */ |
| 438 | if (do_tick) tick[p-lcopy] = '_'; |
| 439 | } |
| 440 | |
| 441 | BAIL: |
| 442 | free(hname); |
| 443 | free(lcopy); |
| 444 | return rc; |
| 445 | } |
| 446 | |
| 447 | |
| 448 | /* -------------------------------------------------------------------------- */ |
| 449 | /* Performs "relaxed" canonicalization of a header. The returned pointer needs |
| 450 | to be free()d. */ |
| 451 | |
| 452 | static char * |
| 453 | pdkim_relax_header (char *header, int crlf) |
| 454 | { |
| 455 | BOOL past_field_name = FALSE; |
| 456 | BOOL seen_wsp = FALSE; |
| 457 | char *p; |
| 458 | char *q; |
| 459 | char *relaxed = malloc(strlen(header)+3); |
| 460 | |
| 461 | if (!relaxed) return NULL; |
| 462 | |
| 463 | q = relaxed; |
| 464 | for (p = header; *p != '\0'; p++) |
| 465 | { |
| 466 | int c = *p; |
| 467 | /* Ignore CR & LF */ |
| 468 | if (c == '\r' || c == '\n') |
| 469 | continue; |
| 470 | if (c == '\t' || c == ' ') |
| 471 | { |
| 472 | if (seen_wsp) |
| 473 | continue; |
| 474 | c = ' '; /* Turns WSP into SP */ |
| 475 | seen_wsp = TRUE; |
| 476 | } |
| 477 | else |
| 478 | if (!past_field_name && c == ':') |
| 479 | { |
| 480 | if (seen_wsp) q--; /* This removes WSP before the colon */ |
| 481 | seen_wsp = TRUE; /* This removes WSP after the colon */ |
| 482 | past_field_name = TRUE; |
| 483 | } |
| 484 | else |
| 485 | seen_wsp = FALSE; |
| 486 | |
| 487 | /* Lowercase header name */ |
| 488 | if (!past_field_name) c = tolower(c); |
| 489 | *q++ = c; |
| 490 | } |
| 491 | |
| 492 | if (q > relaxed && q[-1] == ' ') q--; /* Squash eventual trailing SP */ |
| 493 | *q = '\0'; |
| 494 | |
| 495 | if (crlf) strcat(relaxed, "\r\n"); |
| 496 | return relaxed; |
| 497 | } |
| 498 | |
| 499 | |
| 500 | /* -------------------------------------------------------------------------- */ |
| 501 | #define PDKIM_QP_ERROR_DECODE -1 |
| 502 | |
| 503 | static char * |
| 504 | pdkim_decode_qp_char(char *qp_p, int *c) |
| 505 | { |
| 506 | char *initial_pos = qp_p; |
| 507 | |
| 508 | /* Advance one char */ |
| 509 | qp_p++; |
| 510 | |
| 511 | /* Check for two hex digits and decode them */ |
| 512 | if (isxdigit(*qp_p) && isxdigit(qp_p[1])) |
| 513 | { |
| 514 | /* Do hex conversion */ |
| 515 | *c = (isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10) << 4; |
| 516 | *c |= isdigit(qp_p[1]) ? qp_p[1] - '0' : toupper(qp_p[1]) - 'A' + 10; |
| 517 | return qp_p + 2; |
| 518 | } |
| 519 | |
| 520 | /* Illegal char here */ |
| 521 | *c = PDKIM_QP_ERROR_DECODE; |
| 522 | return initial_pos; |
| 523 | } |
| 524 | |
| 525 | |
| 526 | /* -------------------------------------------------------------------------- */ |
| 527 | |
| 528 | static char * |
| 529 | pdkim_decode_qp(char *str) |
| 530 | { |
| 531 | int nchar = 0; |
| 532 | char *q; |
| 533 | char *p = str; |
| 534 | char *n = malloc(strlen(p)+1); |
| 535 | |
| 536 | if (!n) return NULL; |
| 537 | |
| 538 | *n = '\0'; |
| 539 | q = n; |
| 540 | while (*p != '\0') |
| 541 | { |
| 542 | if (*p == '=') |
| 543 | { |
| 544 | p = pdkim_decode_qp_char(p, &nchar); |
| 545 | if (nchar >= 0) |
| 546 | { |
| 547 | *q++ = nchar; |
| 548 | continue; |
| 549 | } |
| 550 | } |
| 551 | else |
| 552 | *q++ = *p; |
| 553 | p++; |
| 554 | } |
| 555 | *q = '\0'; |
| 556 | return n; |
| 557 | } |
| 558 | |
| 559 | |
| 560 | /* -------------------------------------------------------------------------- */ |
| 561 | |
| 562 | static char * |
| 563 | pdkim_decode_base64(char *str, int *num_decoded) |
| 564 | { |
| 565 | int dlen = 0; |
| 566 | char *res; |
| 567 | int old_pool = store_pool; |
| 568 | |
| 569 | /* There is a store-reset between header & body reception |
| 570 | so cannot use the main pool */ |
| 571 | |
| 572 | store_pool = POOL_PERM; |
| 573 | dlen = b64decode(US str, USS &res); |
| 574 | store_pool = old_pool; |
| 575 | |
| 576 | if (dlen < 0) return NULL; |
| 577 | |
| 578 | if (num_decoded) *num_decoded = dlen; |
| 579 | return res; |
| 580 | } |
| 581 | |
| 582 | |
| 583 | /* -------------------------------------------------------------------------- */ |
| 584 | |
| 585 | static char * |
| 586 | pdkim_encode_base64(char *str, int num) |
| 587 | { |
| 588 | char * ret; |
| 589 | int old_pool = store_pool; |
| 590 | |
| 591 | store_pool = POOL_PERM; |
| 592 | ret = CS b64encode(US str, num); |
| 593 | store_pool = old_pool; |
| 594 | return ret; |
| 595 | } |
| 596 | |
| 597 | |
| 598 | /* -------------------------------------------------------------------------- */ |
| 599 | #define PDKIM_HDR_LIMBO 0 |
| 600 | #define PDKIM_HDR_TAG 1 |
| 601 | #define PDKIM_HDR_VALUE 2 |
| 602 | |
| 603 | static pdkim_signature * |
| 604 | pdkim_parse_sig_header(pdkim_ctx *ctx, char *raw_hdr) |
| 605 | { |
| 606 | pdkim_signature *sig ; |
| 607 | char *p, *q; |
| 608 | pdkim_str *cur_tag = NULL; |
| 609 | pdkim_str *cur_val = NULL; |
| 610 | BOOL past_hname = FALSE; |
| 611 | BOOL in_b_val = FALSE; |
| 612 | int where = PDKIM_HDR_LIMBO; |
| 613 | int i; |
| 614 | |
| 615 | if (!(sig = malloc(sizeof(pdkim_signature)))) return NULL; |
| 616 | memset(sig, 0, sizeof(pdkim_signature)); |
| 617 | sig->bodylength = -1; |
| 618 | |
| 619 | if (!(sig->rawsig_no_b_val = malloc(strlen(raw_hdr)+1))) |
| 620 | { |
| 621 | free(sig); |
| 622 | return NULL; |
| 623 | } |
| 624 | |
| 625 | q = sig->rawsig_no_b_val; |
| 626 | |
| 627 | for (p = raw_hdr; ; p++) |
| 628 | { |
| 629 | char c = *p; |
| 630 | |
| 631 | /* Ignore FWS */ |
| 632 | if (c == '\r' || c == '\n') |
| 633 | goto NEXT_CHAR; |
| 634 | |
| 635 | /* Fast-forward through header name */ |
| 636 | if (!past_hname) |
| 637 | { |
| 638 | if (c == ':') past_hname = TRUE; |
| 639 | goto NEXT_CHAR; |
| 640 | } |
| 641 | |
| 642 | if (where == PDKIM_HDR_LIMBO) |
| 643 | { |
| 644 | /* In limbo, just wait for a tag-char to appear */ |
| 645 | if (!(c >= 'a' && c <= 'z')) |
| 646 | goto NEXT_CHAR; |
| 647 | |
| 648 | where = PDKIM_HDR_TAG; |
| 649 | } |
| 650 | |
| 651 | if (where == PDKIM_HDR_TAG) |
| 652 | { |
| 653 | if (!cur_tag) |
| 654 | cur_tag = pdkim_strnew(NULL); |
| 655 | |
| 656 | if (c >= 'a' && c <= 'z') |
| 657 | pdkim_strncat(cur_tag, p, 1); |
| 658 | |
| 659 | if (c == '=') |
| 660 | { |
| 661 | if (strcmp(cur_tag->str, "b") == 0) |
| 662 | { |
| 663 | *q = '='; q++; |
| 664 | in_b_val = TRUE; |
| 665 | } |
| 666 | where = PDKIM_HDR_VALUE; |
| 667 | goto NEXT_CHAR; |
| 668 | } |
| 669 | } |
| 670 | |
| 671 | if (where == PDKIM_HDR_VALUE) |
| 672 | { |
| 673 | if (!cur_val) |
| 674 | cur_val = pdkim_strnew(NULL); |
| 675 | |
| 676 | if (c == '\r' || c == '\n' || c == ' ' || c == '\t') |
| 677 | goto NEXT_CHAR; |
| 678 | |
| 679 | if (c == ';' || c == '\0') |
| 680 | { |
| 681 | if (cur_tag->len > 0) |
| 682 | { |
| 683 | pdkim_strtrim(cur_val); |
| 684 | |
| 685 | DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag->str, cur_val->str); |
| 686 | |
| 687 | switch (cur_tag->str[0]) |
| 688 | { |
| 689 | case 'b': |
| 690 | if (cur_tag->str[1] == 'h') |
| 691 | sig->bodyhash = pdkim_decode_base64(cur_val->str, |
| 692 | &sig->bodyhash_len); |
| 693 | else |
| 694 | sig->sigdata = pdkim_decode_base64(cur_val->str, |
| 695 | &sig->sigdata_len); |
| 696 | break; |
| 697 | case 'v': |
| 698 | /* We only support version 1, and that is currently the |
| 699 | only version there is. */ |
| 700 | if (strcmp(cur_val->str, PDKIM_SIGNATURE_VERSION) == 0) |
| 701 | sig->version = 1; |
| 702 | break; |
| 703 | case 'a': |
| 704 | for (i = 0; pdkim_algos[i]; i++) |
| 705 | if (strcmp(cur_val->str, pdkim_algos[i]) == 0) |
| 706 | { |
| 707 | sig->algo = i; |
| 708 | break; |
| 709 | } |
| 710 | break; |
| 711 | case 'c': |
| 712 | for (i = 0; pdkim_combined_canons[i].str; i++) |
| 713 | if (strcmp(cur_val->str, pdkim_combined_canons[i].str) == 0) |
| 714 | { |
| 715 | sig->canon_headers = pdkim_combined_canons[i].canon_headers; |
| 716 | sig->canon_body = pdkim_combined_canons[i].canon_body; |
| 717 | break; |
| 718 | } |
| 719 | break; |
| 720 | case 'q': |
| 721 | for (i = 0; pdkim_querymethods[i]; i++) |
| 722 | if (strcmp(cur_val->str, pdkim_querymethods[i]) == 0) |
| 723 | { |
| 724 | sig->querymethod = i; |
| 725 | break; |
| 726 | } |
| 727 | break; |
| 728 | case 's': |
| 729 | sig->selector = strdup(cur_val->str); break; |
| 730 | case 'd': |
| 731 | sig->domain = strdup(cur_val->str); break; |
| 732 | case 'i': |
| 733 | sig->identity = pdkim_decode_qp(cur_val->str); break; |
| 734 | case 't': |
| 735 | sig->created = strtoul(cur_val->str, NULL, 10); break; |
| 736 | case 'x': |
| 737 | sig->expires = strtoul(cur_val->str, NULL, 10); break; |
| 738 | case 'l': |
| 739 | sig->bodylength = strtol(cur_val->str, NULL, 10); break; |
| 740 | case 'h': |
| 741 | sig->headernames = strdup(cur_val->str); break; |
| 742 | case 'z': |
| 743 | sig->copiedheaders = pdkim_decode_qp(cur_val->str); break; |
| 744 | default: |
| 745 | DEBUG(D_acl) debug_printf(" Unknown tag encountered\n"); |
| 746 | break; |
| 747 | } |
| 748 | } |
| 749 | pdkim_strclear(cur_tag); |
| 750 | pdkim_strclear(cur_val); |
| 751 | in_b_val = FALSE; |
| 752 | where = PDKIM_HDR_LIMBO; |
| 753 | } |
| 754 | else |
| 755 | pdkim_strncat(cur_val, p, 1); |
| 756 | } |
| 757 | |
| 758 | NEXT_CHAR: |
| 759 | if (c == '\0') |
| 760 | break; |
| 761 | |
| 762 | if (!in_b_val) |
| 763 | *q++ = c; |
| 764 | } |
| 765 | |
| 766 | /* Make sure the most important bits are there. */ |
| 767 | if (!(sig->domain && (*(sig->domain) != '\0') && |
| 768 | sig->selector && (*(sig->selector) != '\0') && |
| 769 | sig->headernames && (*(sig->headernames) != '\0') && |
| 770 | sig->bodyhash && |
| 771 | sig->sigdata && |
| 772 | sig->version)) |
| 773 | { |
| 774 | pdkim_free_sig(sig); |
| 775 | return NULL; |
| 776 | } |
| 777 | |
| 778 | *q = '\0'; |
| 779 | /* Chomp raw header. The final newline must not be added to the signature. */ |
| 780 | q--; |
| 781 | while (q > sig->rawsig_no_b_val && (*q == '\r' || *q == '\n')) |
| 782 | *q = '\0'; q--; /*XXX questionable code layout; possible bug */ |
| 783 | |
| 784 | DEBUG(D_acl) |
| 785 | { |
| 786 | debug_printf( |
| 787 | "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); |
| 788 | pdkim_quoteprint(sig->rawsig_no_b_val, strlen(sig->rawsig_no_b_val), 1); |
| 789 | debug_printf( |
| 790 | "PDKIM >> Sig size: %4d bits\n", sig->sigdata_len*8); |
| 791 | debug_printf( |
| 792 | "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); |
| 793 | } |
| 794 | |
| 795 | #ifdef SHA_OPENSSL |
| 796 | |
| 797 | SHA1_Init (&sig->sha1_body); |
| 798 | SHA256_Init(&sig->sha2_body); |
| 799 | |
| 800 | #elif defined(SHA_GNUTLS) |
| 801 | |
| 802 | gnutls_hash_init(&sig->sha_body, |
| 803 | sig->algo == PDKIM_ALGO_RSA_SHA1 ? GNUTLS_DIG_SHA1 : GNUTLS_DIG_SHA256); |
| 804 | |
| 805 | #elif defined(SHA_POLARSSL) |
| 806 | |
| 807 | if ( !(sig->sha1_body = malloc(sizeof(sha1_context))) |
| 808 | || !(sig->sha2_body = malloc(sizeof(sha2_context))) |
| 809 | ) |
| 810 | { |
| 811 | pdkim_free_sig(sig); |
| 812 | return NULL; |
| 813 | } |
| 814 | |
| 815 | sha1_starts(sig->sha1_body); |
| 816 | sha2_starts(sig->sha2_body, 0); |
| 817 | |
| 818 | #endif /* SHA impl */ |
| 819 | |
| 820 | return sig; |
| 821 | } |
| 822 | |
| 823 | |
| 824 | /* -------------------------------------------------------------------------- */ |
| 825 | |
| 826 | static pdkim_pubkey * |
| 827 | pdkim_parse_pubkey_record(pdkim_ctx *ctx, char *raw_record) |
| 828 | { |
| 829 | pdkim_pubkey *pub; |
| 830 | char *p; |
| 831 | pdkim_str *cur_tag = NULL; |
| 832 | pdkim_str *cur_val = NULL; |
| 833 | int where = PDKIM_HDR_LIMBO; |
| 834 | |
| 835 | if (!(pub = malloc(sizeof(pdkim_pubkey)))) return NULL; |
| 836 | memset(pub, 0, sizeof(pdkim_pubkey)); |
| 837 | |
| 838 | for (p = raw_record; ; p++) |
| 839 | { |
| 840 | char c = *p; |
| 841 | |
| 842 | /* Ignore FWS */ |
| 843 | if (c == '\r' || c == '\n') |
| 844 | goto NEXT_CHAR; |
| 845 | |
| 846 | if (where == PDKIM_HDR_LIMBO) |
| 847 | { |
| 848 | /* In limbo, just wait for a tag-char to appear */ |
| 849 | if (!(c >= 'a' && c <= 'z')) |
| 850 | goto NEXT_CHAR; |
| 851 | |
| 852 | where = PDKIM_HDR_TAG; |
| 853 | } |
| 854 | |
| 855 | if (where == PDKIM_HDR_TAG) |
| 856 | { |
| 857 | if (!cur_tag) |
| 858 | cur_tag = pdkim_strnew(NULL); |
| 859 | |
| 860 | if (c >= 'a' && c <= 'z') |
| 861 | pdkim_strncat(cur_tag, p, 1); |
| 862 | |
| 863 | if (c == '=') |
| 864 | { |
| 865 | where = PDKIM_HDR_VALUE; |
| 866 | goto NEXT_CHAR; |
| 867 | } |
| 868 | } |
| 869 | |
| 870 | if (where == PDKIM_HDR_VALUE) |
| 871 | { |
| 872 | if (!cur_val) |
| 873 | cur_val = pdkim_strnew(NULL); |
| 874 | |
| 875 | if (c == '\r' || c == '\n') |
| 876 | goto NEXT_CHAR; |
| 877 | |
| 878 | if (c == ';' || c == '\0') |
| 879 | { |
| 880 | if (cur_tag->len > 0) |
| 881 | { |
| 882 | pdkim_strtrim(cur_val); |
| 883 | DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag->str, cur_val->str); |
| 884 | |
| 885 | switch (cur_tag->str[0]) |
| 886 | { |
| 887 | case 'v': |
| 888 | /* This tag isn't evaluated because: |
| 889 | - We only support version DKIM1. |
| 890 | - Which is the default for this value (set below) |
| 891 | - Other versions are currently not specified. */ |
| 892 | break; |
| 893 | case 'h': |
| 894 | pub->hashes = strdup(cur_val->str); break; |
| 895 | case 'g': |
| 896 | pub->granularity = strdup(cur_val->str); break; |
| 897 | case 'n': |
| 898 | pub->notes = pdkim_decode_qp(cur_val->str); break; |
| 899 | case 'p': |
| 900 | pub->key = pdkim_decode_base64(cur_val->str, &(pub->key_len)); break; |
| 901 | case 'k': |
| 902 | pub->hashes = strdup(cur_val->str); break; |
| 903 | case 's': |
| 904 | pub->srvtype = strdup(cur_val->str); break; |
| 905 | case 't': |
| 906 | if (strchr(cur_val->str, 'y') != NULL) pub->testing = 1; |
| 907 | if (strchr(cur_val->str, 's') != NULL) pub->no_subdomaining = 1; |
| 908 | break; |
| 909 | default: |
| 910 | DEBUG(D_acl) debug_printf(" Unknown tag encountered\n"); |
| 911 | break; |
| 912 | } |
| 913 | } |
| 914 | pdkim_strclear(cur_tag); |
| 915 | pdkim_strclear(cur_val); |
| 916 | where = PDKIM_HDR_LIMBO; |
| 917 | } |
| 918 | else |
| 919 | pdkim_strncat(cur_val, p, 1); |
| 920 | } |
| 921 | |
| 922 | NEXT_CHAR: |
| 923 | if (c == '\0') break; |
| 924 | } |
| 925 | |
| 926 | /* Set fallback defaults */ |
| 927 | if (!pub->version ) pub->version = strdup(PDKIM_PUB_RECORD_VERSION); |
| 928 | if (!pub->granularity) pub->granularity = strdup("*"); |
| 929 | if (!pub->keytype ) pub->keytype = strdup("rsa"); |
| 930 | if (!pub->srvtype ) pub->srvtype = strdup("*"); |
| 931 | |
| 932 | /* p= is required */ |
| 933 | if (pub->key) |
| 934 | return pub; |
| 935 | |
| 936 | pdkim_free_pubkey(pub); |
| 937 | return NULL; |
| 938 | } |
| 939 | |
| 940 | |
| 941 | /* -------------------------------------------------------------------------- */ |
| 942 | |
| 943 | static int |
| 944 | pdkim_update_bodyhash(pdkim_ctx *ctx, const char *data, int len) |
| 945 | { |
| 946 | pdkim_signature *sig = ctx->sig; |
| 947 | /* Cache relaxed version of data */ |
| 948 | char *relaxed_data = NULL; |
| 949 | int relaxed_len = 0; |
| 950 | |
| 951 | /* Traverse all signatures, updating their hashes. */ |
| 952 | while (sig) |
| 953 | { |
| 954 | /* Defaults to simple canon (no further treatment necessary) */ |
| 955 | const char *canon_data = data; |
| 956 | int canon_len = len; |
| 957 | |
| 958 | if (sig->canon_body == PDKIM_CANON_RELAXED) |
| 959 | { |
| 960 | /* Relax the line if not done already */ |
| 961 | if (!relaxed_data) |
| 962 | { |
| 963 | BOOL seen_wsp = FALSE; |
| 964 | const char *p; |
| 965 | int q = 0; |
| 966 | |
| 967 | if (!(relaxed_data = malloc(len+1))) |
| 968 | return PDKIM_ERR_OOM; |
| 969 | |
| 970 | for (p = data; *p; p++) |
| 971 | { |
| 972 | char c = *p; |
| 973 | if (c == '\r') |
| 974 | { |
| 975 | if (q > 0 && relaxed_data[q-1] == ' ') |
| 976 | q--; |
| 977 | } |
| 978 | else if (c == '\t' || c == ' ') |
| 979 | { |
| 980 | c = ' '; /* Turns WSP into SP */ |
| 981 | if (seen_wsp) |
| 982 | continue; |
| 983 | seen_wsp = TRUE; |
| 984 | } |
| 985 | else |
| 986 | seen_wsp = FALSE; |
| 987 | relaxed_data[q++] = c; |
| 988 | } |
| 989 | relaxed_data[q] = '\0'; |
| 990 | relaxed_len = q; |
| 991 | } |
| 992 | canon_data = relaxed_data; |
| 993 | canon_len = relaxed_len; |
| 994 | } |
| 995 | |
| 996 | /* Make sure we don't exceed the to-be-signed body length */ |
| 997 | if ( sig->bodylength >= 0 |
| 998 | && sig->signed_body_bytes + (unsigned long)canon_len > sig->bodylength |
| 999 | ) |
| 1000 | canon_len = sig->bodylength - sig->signed_body_bytes; |
| 1001 | |
| 1002 | if (canon_len > 0) |
| 1003 | { |
| 1004 | #ifdef SHA_GNUTLS |
| 1005 | gnutls_hash(sig->sha_body, canon_data, canon_len); |
| 1006 | #else |
| 1007 | if (sig->algo == PDKIM_ALGO_RSA_SHA1) |
| 1008 | # ifdef SHA_OPENSSL |
| 1009 | SHA1_Update (&sig->sha1_body, canon_data, canon_len); |
| 1010 | else |
| 1011 | SHA256_Update(&sig->sha2_body, canon_data, canon_len); |
| 1012 | # elif defined(SHA_POLARSSL) |
| 1013 | sha1_update(sig->sha1_body, US canon_data, canon_len); |
| 1014 | else |
| 1015 | sha2_update(sig->sha2_body, US canon_data, canon_len); |
| 1016 | # endif |
| 1017 | #endif |
| 1018 | |
| 1019 | sig->signed_body_bytes += canon_len; |
| 1020 | DEBUG(D_acl) pdkim_quoteprint(canon_data, canon_len, 1); |
| 1021 | } |
| 1022 | |
| 1023 | sig = sig->next; |
| 1024 | } |
| 1025 | |
| 1026 | if (relaxed_data) free(relaxed_data); |
| 1027 | return PDKIM_OK; |
| 1028 | } |
| 1029 | |
| 1030 | |
| 1031 | /* -------------------------------------------------------------------------- */ |
| 1032 | |
| 1033 | static int |
| 1034 | pdkim_finish_bodyhash(pdkim_ctx *ctx) |
| 1035 | { |
| 1036 | pdkim_signature *sig; |
| 1037 | |
| 1038 | /* Traverse all signatures */ |
| 1039 | for (sig = ctx->sig; sig; sig = sig->next) |
| 1040 | { /* Finish hashes */ |
| 1041 | uschar bh[32]; /* SHA-256 = 32 Bytes, SHA-1 = 20 Bytes */ |
| 1042 | |
| 1043 | #ifdef SHA_GNUTLS |
| 1044 | gnutls_hash_output(sig->sha_body, bh); |
| 1045 | #else |
| 1046 | if (sig->algo == PDKIM_ALGO_RSA_SHA1) |
| 1047 | # ifdef SHA_OPENSSL |
| 1048 | SHA1_Final (bh, &sig->sha1_body); |
| 1049 | else |
| 1050 | SHA256_Final(bh, &sig->sha2_body); |
| 1051 | # elif defined(SHA_POLARSSL) |
| 1052 | sha1_finish(sig->sha1_body, bh); |
| 1053 | else |
| 1054 | sha2_finish(sig->sha2_body, bh); |
| 1055 | # endif |
| 1056 | #endif |
| 1057 | |
| 1058 | DEBUG(D_acl) |
| 1059 | { |
| 1060 | debug_printf("PDKIM [%s] Body bytes hashed: %lu\n" |
| 1061 | "PDKIM [%s] bh computed: ", |
| 1062 | sig->domain, sig->signed_body_bytes, sig->domain); |
| 1063 | pdkim_hexprint((char *)bh, sig->algo == PDKIM_ALGO_RSA_SHA1 ? 20 : 32, 1); |
| 1064 | } |
| 1065 | |
| 1066 | /* SIGNING -------------------------------------------------------------- */ |
| 1067 | if (ctx->mode == PDKIM_MODE_SIGN) |
| 1068 | { |
| 1069 | sig->bodyhash_len = sig->algo == PDKIM_ALGO_RSA_SHA1 ? 20:32; |
| 1070 | sig->bodyhash = string_copyn(US bh, sig->bodyhash_len); |
| 1071 | |
| 1072 | /* If bodylength limit is set, and we have received less bytes |
| 1073 | than the requested amount, effectively remove the limit tag. */ |
| 1074 | if (sig->signed_body_bytes < sig->bodylength) |
| 1075 | sig->bodylength = -1; |
| 1076 | } |
| 1077 | |
| 1078 | /* VERIFICATION --------------------------------------------------------- */ |
| 1079 | else |
| 1080 | { |
| 1081 | /* Compare bodyhash */ |
| 1082 | if (memcmp(bh, sig->bodyhash, |
| 1083 | (sig->algo == PDKIM_ALGO_RSA_SHA1)?20:32) == 0) |
| 1084 | { |
| 1085 | DEBUG(D_acl) debug_printf("PDKIM [%s] Body hash verified OK\n", sig->domain); |
| 1086 | } |
| 1087 | else |
| 1088 | { |
| 1089 | DEBUG(D_acl) |
| 1090 | { |
| 1091 | debug_printf("PDKIM [%s] bh signature: ", sig->domain); |
| 1092 | pdkim_hexprint(sig->bodyhash, |
| 1093 | sig->algo == PDKIM_ALGO_RSA_SHA1 ? 20 : 32, 1); |
| 1094 | debug_printf("PDKIM [%s] Body hash did NOT verify\n", sig->domain); |
| 1095 | } |
| 1096 | sig->verify_status = PDKIM_VERIFY_FAIL; |
| 1097 | sig->verify_ext_status = PDKIM_VERIFY_FAIL_BODY; |
| 1098 | } |
| 1099 | } |
| 1100 | } |
| 1101 | |
| 1102 | return PDKIM_OK; |
| 1103 | } |
| 1104 | |
| 1105 | |
| 1106 | |
| 1107 | /* -------------------------------------------------------------------------- */ |
| 1108 | /* Callback from pdkim_feed below for processing complete body lines */ |
| 1109 | |
| 1110 | static int |
| 1111 | pdkim_bodyline_complete(pdkim_ctx *ctx) |
| 1112 | { |
| 1113 | char *p = ctx->linebuf; |
| 1114 | int n = ctx->linebuf_offset; |
| 1115 | pdkim_signature *sig = ctx->sig; /*XXX assumes only one sig */ |
| 1116 | |
| 1117 | /* Ignore extra data if we've seen the end-of-data marker */ |
| 1118 | if (ctx->seen_eod) goto BAIL; |
| 1119 | |
| 1120 | /* We've always got one extra byte to stuff a zero ... */ |
| 1121 | ctx->linebuf[ctx->linebuf_offset] = '\0'; |
| 1122 | |
| 1123 | /* Terminate on EOD marker */ |
| 1124 | if (memcmp(p, ".\r\n", 3) == 0) |
| 1125 | { |
| 1126 | /* In simple body mode, if any empty lines were buffered, |
| 1127 | replace with one. rfc 4871 3.4.3 */ |
| 1128 | /*XXX checking the signed-body-bytes is a gross hack; I think |
| 1129 | it indicates that all linebreaks should be buffered, including |
| 1130 | the one terminating a text line */ |
| 1131 | if ( sig && sig->canon_body == PDKIM_CANON_SIMPLE |
| 1132 | && sig->signed_body_bytes == 0 |
| 1133 | && ctx->num_buffered_crlf > 0 |
| 1134 | ) |
| 1135 | pdkim_update_bodyhash(ctx, "\r\n", 2); |
| 1136 | |
| 1137 | ctx->seen_eod = TRUE; |
| 1138 | goto BAIL; |
| 1139 | } |
| 1140 | /* Unstuff dots */ |
| 1141 | if (memcmp(p, "..", 2) == 0) |
| 1142 | { |
| 1143 | p++; |
| 1144 | n--; |
| 1145 | } |
| 1146 | |
| 1147 | /* Empty lines need to be buffered until we find a non-empty line */ |
| 1148 | if (memcmp(p, "\r\n", 2) == 0) |
| 1149 | { |
| 1150 | ctx->num_buffered_crlf++; |
| 1151 | goto BAIL; |
| 1152 | } |
| 1153 | |
| 1154 | if (sig && sig->canon_body == PDKIM_CANON_RELAXED) |
| 1155 | { |
| 1156 | /* Lines with just spaces need to be buffered too */ |
| 1157 | char *check = p; |
| 1158 | while (memcmp(check, "\r\n", 2) != 0) |
| 1159 | { |
| 1160 | char c = *check; |
| 1161 | |
| 1162 | if (c != '\t' && c != ' ') |
| 1163 | goto PROCESS; |
| 1164 | check++; |
| 1165 | } |
| 1166 | |
| 1167 | ctx->num_buffered_crlf++; |
| 1168 | goto BAIL; |
| 1169 | } |
| 1170 | |
| 1171 | PROCESS: |
| 1172 | /* At this point, we have a non-empty line, so release the buffered ones. */ |
| 1173 | while (ctx->num_buffered_crlf) |
| 1174 | { |
| 1175 | pdkim_update_bodyhash(ctx, "\r\n", 2); |
| 1176 | ctx->num_buffered_crlf--; |
| 1177 | } |
| 1178 | |
| 1179 | pdkim_update_bodyhash(ctx, p, n); |
| 1180 | |
| 1181 | BAIL: |
| 1182 | ctx->linebuf_offset = 0; |
| 1183 | return PDKIM_OK; |
| 1184 | } |
| 1185 | |
| 1186 | |
| 1187 | /* -------------------------------------------------------------------------- */ |
| 1188 | /* Callback from pdkim_feed below for processing complete headers */ |
| 1189 | #define DKIM_SIGNATURE_HEADERNAME "DKIM-Signature:" |
| 1190 | |
| 1191 | static int |
| 1192 | pdkim_header_complete(pdkim_ctx *ctx) |
| 1193 | { |
| 1194 | /* Special case: The last header can have an extra \r appended */ |
| 1195 | if ( (ctx->cur_header->len > 1) && |
| 1196 | (ctx->cur_header->str[(ctx->cur_header->len)-1] == '\r') ) |
| 1197 | { |
| 1198 | ctx->cur_header->str[(ctx->cur_header->len)-1] = '\0'; |
| 1199 | ctx->cur_header->len--; |
| 1200 | } |
| 1201 | |
| 1202 | ctx->num_headers++; |
| 1203 | if (ctx->num_headers > PDKIM_MAX_HEADERS) goto BAIL; |
| 1204 | |
| 1205 | /* SIGNING -------------------------------------------------------------- */ |
| 1206 | if (ctx->mode == PDKIM_MODE_SIGN) |
| 1207 | { |
| 1208 | pdkim_signature *sig; |
| 1209 | |
| 1210 | for (sig = ctx->sig; sig; sig = sig->next) /* Traverse all signatures */ |
| 1211 | if (header_name_match(ctx->cur_header->str, |
| 1212 | sig->sign_headers? |
| 1213 | sig->sign_headers: |
| 1214 | PDKIM_DEFAULT_SIGN_HEADERS, 0) == PDKIM_OK) |
| 1215 | { |
| 1216 | pdkim_stringlist *list; |
| 1217 | |
| 1218 | /* Add header to the signed headers list (in reverse order) */ |
| 1219 | if (!(list = pdkim_prepend_stringlist(sig->headers, |
| 1220 | ctx->cur_header->str))) |
| 1221 | return PDKIM_ERR_OOM; |
| 1222 | sig->headers = list; |
| 1223 | } |
| 1224 | } |
| 1225 | |
| 1226 | /* VERIFICATION ----------------------------------------------------------- */ |
| 1227 | /* DKIM-Signature: headers are added to the verification list */ |
| 1228 | if (ctx->mode == PDKIM_MODE_VERIFY) |
| 1229 | { |
| 1230 | if (strncasecmp(ctx->cur_header->str, |
| 1231 | DKIM_SIGNATURE_HEADERNAME, |
| 1232 | strlen(DKIM_SIGNATURE_HEADERNAME)) == 0) |
| 1233 | { |
| 1234 | pdkim_signature *new_sig; |
| 1235 | |
| 1236 | /* Create and chain new signature block */ |
| 1237 | DEBUG(D_acl) debug_printf( |
| 1238 | "PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); |
| 1239 | |
| 1240 | if ((new_sig = pdkim_parse_sig_header(ctx, ctx->cur_header->str))) |
| 1241 | { |
| 1242 | pdkim_signature *last_sig = ctx->sig; |
| 1243 | if (!last_sig) |
| 1244 | ctx->sig = new_sig; |
| 1245 | else |
| 1246 | { |
| 1247 | while (last_sig->next) last_sig = last_sig->next; |
| 1248 | last_sig->next = new_sig; |
| 1249 | } |
| 1250 | } |
| 1251 | else |
| 1252 | DEBUG(D_acl) debug_printf( |
| 1253 | "Error while parsing signature header\n" |
| 1254 | "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); |
| 1255 | } |
| 1256 | |
| 1257 | /* every other header is stored for signature verification */ |
| 1258 | else |
| 1259 | { |
| 1260 | pdkim_stringlist *list; |
| 1261 | |
| 1262 | if (!(list = pdkim_prepend_stringlist(ctx->headers, ctx->cur_header->str))) |
| 1263 | return PDKIM_ERR_OOM; |
| 1264 | ctx->headers = list; |
| 1265 | } |
| 1266 | } |
| 1267 | |
| 1268 | BAIL: |
| 1269 | pdkim_strclear(ctx->cur_header); /* Re-use existing pdkim_str */ |
| 1270 | return PDKIM_OK; |
| 1271 | } |
| 1272 | |
| 1273 | |
| 1274 | |
| 1275 | /* -------------------------------------------------------------------------- */ |
| 1276 | #define HEADER_BUFFER_FRAG_SIZE 256 |
| 1277 | |
| 1278 | DLLEXPORT int |
| 1279 | pdkim_feed (pdkim_ctx *ctx, char *data, int len) |
| 1280 | { |
| 1281 | int p; |
| 1282 | |
| 1283 | for (p = 0; p<len; p++) |
| 1284 | { |
| 1285 | char c = data[p]; |
| 1286 | |
| 1287 | if (ctx->past_headers) |
| 1288 | { |
| 1289 | /* Processing body byte */ |
| 1290 | ctx->linebuf[ctx->linebuf_offset++] = c; |
| 1291 | if (c == '\n') |
| 1292 | { |
| 1293 | int rc = pdkim_bodyline_complete(ctx); /* End of line */ |
| 1294 | if (rc != PDKIM_OK) return rc; |
| 1295 | } |
| 1296 | if (ctx->linebuf_offset == (PDKIM_MAX_BODY_LINE_LEN-1)) |
| 1297 | return PDKIM_ERR_LONG_LINE; |
| 1298 | } |
| 1299 | else |
| 1300 | { |
| 1301 | /* Processing header byte */ |
| 1302 | if (c != '\r') |
| 1303 | { |
| 1304 | if (c == '\n') |
| 1305 | { |
| 1306 | if (ctx->seen_lf) |
| 1307 | { |
| 1308 | int rc = pdkim_header_complete(ctx); /* Seen last header line */ |
| 1309 | if (rc != PDKIM_OK) return rc; |
| 1310 | |
| 1311 | ctx->past_headers = TRUE; |
| 1312 | ctx->seen_lf = 0; |
| 1313 | DEBUG(D_acl) debug_printf( |
| 1314 | "PDKIM >> Hashed body data, canonicalized >>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); |
| 1315 | continue; |
| 1316 | } |
| 1317 | else |
| 1318 | ctx->seen_lf = TRUE; |
| 1319 | } |
| 1320 | else if (ctx->seen_lf) |
| 1321 | { |
| 1322 | if (!(c == '\t' || c == ' ')) |
| 1323 | { |
| 1324 | int rc = pdkim_header_complete(ctx); /* End of header */ |
| 1325 | if (rc != PDKIM_OK) return rc; |
| 1326 | } |
| 1327 | ctx->seen_lf = FALSE; |
| 1328 | } |
| 1329 | } |
| 1330 | |
| 1331 | if (!ctx->cur_header) |
| 1332 | if (!(ctx->cur_header = pdkim_strnew(NULL))) |
| 1333 | return PDKIM_ERR_OOM; |
| 1334 | |
| 1335 | if (ctx->cur_header->len < PDKIM_MAX_HEADER_LEN) |
| 1336 | if (!pdkim_strncat(ctx->cur_header, &data[p], 1)) |
| 1337 | return PDKIM_ERR_OOM; |
| 1338 | } |
| 1339 | } |
| 1340 | return PDKIM_OK; |
| 1341 | } |
| 1342 | |
| 1343 | /* |
| 1344 | * RFC 5322 specifies that header line length SHOULD be no more than 78 |
| 1345 | * lets make it so! |
| 1346 | * pdkim_headcat |
| 1347 | * returns char* |
| 1348 | * |
| 1349 | * col: this int holds and receives column number (octets since last '\n') |
| 1350 | * str: partial string to append to |
| 1351 | * pad: padding, split line or space after before or after eg: ";" |
| 1352 | * intro: - must join to payload eg "h=", usually the tag name |
| 1353 | * payload: eg base64 data - long data can be split arbitrarily. |
| 1354 | * |
| 1355 | * this code doesn't fold the header in some of the places that RFC4871 |
| 1356 | * allows: As per RFC5322(2.2.3) it only folds before or after tag-value |
| 1357 | * pairs and inside long values. it also always spaces or breaks after the |
| 1358 | * "pad" |
| 1359 | * |
| 1360 | * no guarantees are made for output given out-of range input. like tag |
| 1361 | * names longer than 78, or bogus col. Input is assumed to be free of line breaks. |
| 1362 | */ |
| 1363 | |
| 1364 | static char * |
| 1365 | pdkim_headcat(int *col, pdkim_str *str, const char * pad, |
| 1366 | const char *intro, const char *payload) |
| 1367 | { |
| 1368 | size_t l; |
| 1369 | |
| 1370 | if (pad) |
| 1371 | { |
| 1372 | l = strlen(pad); |
| 1373 | if (*col + l > 78) |
| 1374 | { |
| 1375 | pdkim_strcat(str, "\r\n\t"); |
| 1376 | *col = 1; |
| 1377 | } |
| 1378 | pdkim_strncat(str, pad, l); |
| 1379 | *col += l; |
| 1380 | } |
| 1381 | |
| 1382 | l = (pad?1:0) + (intro?strlen(intro):0); |
| 1383 | |
| 1384 | if (*col + l > 78) |
| 1385 | { /*can't fit intro - start a new line to make room.*/ |
| 1386 | pdkim_strcat(str, "\r\n\t"); |
| 1387 | *col = 1; |
| 1388 | l = intro?strlen(intro):0; |
| 1389 | } |
| 1390 | |
| 1391 | l += payload ? strlen(payload):0 ; |
| 1392 | |
| 1393 | while (l>77) |
| 1394 | { /* this fragment will not fit on a single line */ |
| 1395 | if (pad) |
| 1396 | { |
| 1397 | pdkim_strcat(str, " "); |
| 1398 | *col += 1; |
| 1399 | pad = NULL; /* only want this once */ |
| 1400 | l--; |
| 1401 | } |
| 1402 | |
| 1403 | if (intro) |
| 1404 | { |
| 1405 | size_t sl = strlen(intro); |
| 1406 | |
| 1407 | pdkim_strncat(str, intro, sl); |
| 1408 | *col += sl; |
| 1409 | l -= sl; |
| 1410 | intro = NULL; /* only want this once */ |
| 1411 | } |
| 1412 | |
| 1413 | if (payload) |
| 1414 | { |
| 1415 | size_t sl = strlen(payload); |
| 1416 | size_t chomp = *col+sl < 77 ? sl : 78-*col; |
| 1417 | |
| 1418 | pdkim_strncat(str, payload, chomp); |
| 1419 | *col += chomp; |
| 1420 | payload += chomp; |
| 1421 | l -= chomp-1; |
| 1422 | } |
| 1423 | |
| 1424 | /* the while precondition tells us it didn't fit. */ |
| 1425 | pdkim_strcat(str, "\r\n\t"); |
| 1426 | *col = 1; |
| 1427 | } |
| 1428 | |
| 1429 | if (*col + l > 78) |
| 1430 | { |
| 1431 | pdkim_strcat(str, "\r\n\t"); |
| 1432 | *col = 1; |
| 1433 | pad = NULL; |
| 1434 | } |
| 1435 | |
| 1436 | if (pad) |
| 1437 | { |
| 1438 | pdkim_strcat(str, " "); |
| 1439 | *col += 1; |
| 1440 | pad = NULL; |
| 1441 | } |
| 1442 | |
| 1443 | if (intro) |
| 1444 | { |
| 1445 | size_t sl = strlen(intro); |
| 1446 | |
| 1447 | pdkim_strncat(str, intro, sl); |
| 1448 | *col += sl; |
| 1449 | l -= sl; |
| 1450 | intro = NULL; |
| 1451 | } |
| 1452 | |
| 1453 | if (payload) |
| 1454 | { |
| 1455 | size_t sl = strlen(payload); |
| 1456 | |
| 1457 | pdkim_strncat(str, payload, sl); |
| 1458 | *col += sl; |
| 1459 | } |
| 1460 | |
| 1461 | return str->str; |
| 1462 | } |
| 1463 | |
| 1464 | |
| 1465 | /* -------------------------------------------------------------------------- */ |
| 1466 | |
| 1467 | static char * |
| 1468 | pdkim_create_header(pdkim_signature *sig, int final) |
| 1469 | { |
| 1470 | char *rc = NULL; |
| 1471 | char *base64_bh = NULL; |
| 1472 | char *base64_b = NULL; |
| 1473 | int col = 0; |
| 1474 | pdkim_str *hdr; |
| 1475 | pdkim_str *canon_all; |
| 1476 | |
| 1477 | if (!(hdr = pdkim_strnew("DKIM-Signature: v="PDKIM_SIGNATURE_VERSION))) |
| 1478 | return NULL; |
| 1479 | |
| 1480 | if (!(canon_all = pdkim_strnew(pdkim_canons[sig->canon_headers]))) |
| 1481 | goto BAIL; |
| 1482 | |
| 1483 | if (!(base64_bh = pdkim_encode_base64(sig->bodyhash, sig->bodyhash_len))) |
| 1484 | goto BAIL; |
| 1485 | |
| 1486 | col = strlen(hdr->str); |
| 1487 | |
| 1488 | /* Required and static bits */ |
| 1489 | if ( pdkim_headcat(&col, hdr, ";", "a=", pdkim_algos[sig->algo]) |
| 1490 | && pdkim_headcat(&col, hdr, ";", "q=", pdkim_querymethods[sig->querymethod]) |
| 1491 | && pdkim_strcat(canon_all, "/") |
| 1492 | && pdkim_strcat(canon_all, pdkim_canons[sig->canon_body]) |
| 1493 | && pdkim_headcat(&col, hdr, ";", "c=", canon_all->str) |
| 1494 | && pdkim_headcat(&col, hdr, ";", "d=", sig->domain) |
| 1495 | && pdkim_headcat(&col, hdr, ";", "s=", sig->selector) |
| 1496 | ) |
| 1497 | { |
| 1498 | /* list of eader names can be split between items. */ |
| 1499 | { |
| 1500 | char *n = strdup(sig->headernames); |
| 1501 | char *f = n; |
| 1502 | char *i = "h="; |
| 1503 | char *s = ";"; |
| 1504 | |
| 1505 | if (!n) goto BAIL; |
| 1506 | while (*n) |
| 1507 | { |
| 1508 | char *c = strchr(n, ':'); |
| 1509 | |
| 1510 | if (c) *c ='\0'; |
| 1511 | |
| 1512 | if (!i) |
| 1513 | if (!pdkim_headcat(&col, hdr, NULL, NULL, ":")) |
| 1514 | { |
| 1515 | free(f); |
| 1516 | goto BAIL; |
| 1517 | } |
| 1518 | |
| 1519 | if (!pdkim_headcat(&col, hdr, s, i, n)) |
| 1520 | { |
| 1521 | free(f); |
| 1522 | goto BAIL; |
| 1523 | } |
| 1524 | |
| 1525 | if (!c) |
| 1526 | break; |
| 1527 | |
| 1528 | n = c+1; |
| 1529 | s = NULL; |
| 1530 | i = NULL; |
| 1531 | } |
| 1532 | free(f); |
| 1533 | } |
| 1534 | |
| 1535 | if(!pdkim_headcat(&col, hdr, ";", "bh=", base64_bh)) |
| 1536 | goto BAIL; |
| 1537 | |
| 1538 | /* Optional bits */ |
| 1539 | if (sig->identity) |
| 1540 | if(!pdkim_headcat(&col, hdr, ";", "i=", sig->identity)) |
| 1541 | goto BAIL; |
| 1542 | |
| 1543 | if (sig->created > 0) |
| 1544 | { |
| 1545 | char minibuf[20]; |
| 1546 | |
| 1547 | snprintf(minibuf, 20, "%lu", sig->created); |
| 1548 | if(!pdkim_headcat(&col, hdr, ";", "t=", minibuf)) |
| 1549 | goto BAIL; |
| 1550 | } |
| 1551 | |
| 1552 | if (sig->expires > 0) |
| 1553 | { |
| 1554 | char minibuf[20]; |
| 1555 | |
| 1556 | snprintf(minibuf, 20, "%lu", sig->expires); |
| 1557 | if(!pdkim_headcat(&col, hdr, ";", "x=", minibuf)) |
| 1558 | goto BAIL; |
| 1559 | } |
| 1560 | |
| 1561 | if (sig->bodylength >= 0) |
| 1562 | { |
| 1563 | char minibuf[20]; |
| 1564 | |
| 1565 | snprintf(minibuf, 20, "%lu", sig->bodylength); |
| 1566 | if(!pdkim_headcat(&col, hdr, ";", "l=", minibuf)) |
| 1567 | goto BAIL; |
| 1568 | } |
| 1569 | |
| 1570 | /* Preliminary or final version? */ |
| 1571 | if (final) |
| 1572 | { |
| 1573 | if (!(base64_b = pdkim_encode_base64(sig->sigdata, sig->sigdata_len))) |
| 1574 | goto BAIL; |
| 1575 | if (!pdkim_headcat(&col, hdr, ";", "b=", base64_b)) |
| 1576 | goto BAIL; |
| 1577 | } |
| 1578 | else |
| 1579 | if(!pdkim_headcat(&col, hdr, ";", "b=", "")) |
| 1580 | goto BAIL; |
| 1581 | |
| 1582 | /* add trailing semicolon: I'm not sure if this is actually needed */ |
| 1583 | if (!pdkim_headcat(&col, hdr, NULL, ";", "")) |
| 1584 | goto BAIL; |
| 1585 | } |
| 1586 | |
| 1587 | rc = strdup(hdr->str); |
| 1588 | |
| 1589 | BAIL: |
| 1590 | pdkim_strfree(hdr); |
| 1591 | if (canon_all) pdkim_strfree(canon_all); |
| 1592 | return rc; |
| 1593 | } |
| 1594 | |
| 1595 | |
| 1596 | /* -------------------------------------------------------------------------- */ |
| 1597 | |
| 1598 | DLLEXPORT int |
| 1599 | pdkim_feed_finish(pdkim_ctx *ctx, pdkim_signature **return_signatures) |
| 1600 | { |
| 1601 | pdkim_signature *sig = ctx->sig; |
| 1602 | pdkim_str *headernames = NULL; /* Collected signed header names */ |
| 1603 | |
| 1604 | /* Check if we must still flush a (partial) header. If that is the |
| 1605 | case, the message has no body, and we must compute a body hash |
| 1606 | out of '<CR><LF>' */ |
| 1607 | if (ctx->cur_header && ctx->cur_header->len) |
| 1608 | { |
| 1609 | int rc = pdkim_header_complete(ctx); |
| 1610 | if (rc != PDKIM_OK) return rc; |
| 1611 | pdkim_update_bodyhash(ctx, "\r\n", 2); |
| 1612 | } |
| 1613 | else |
| 1614 | DEBUG(D_acl) debug_printf( |
| 1615 | "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); |
| 1616 | |
| 1617 | /* Build (and/or evaluate) body hash */ |
| 1618 | if (pdkim_finish_bodyhash(ctx) != PDKIM_OK) |
| 1619 | return PDKIM_ERR_OOM; |
| 1620 | |
| 1621 | /* SIGNING -------------------------------------------------------------- */ |
| 1622 | if (ctx->mode == PDKIM_MODE_SIGN) |
| 1623 | if (!(headernames = pdkim_strnew(NULL))) |
| 1624 | return PDKIM_ERR_OOM; |
| 1625 | /* ---------------------------------------------------------------------- */ |
| 1626 | |
| 1627 | while (sig) |
| 1628 | { |
| 1629 | #ifdef SHA_OPENSSL |
| 1630 | SHA_CTX sha1_headers; |
| 1631 | SHA256_CTX sha2_headers; |
| 1632 | #elif defined(SHA_GNUTLS) |
| 1633 | gnutls_hash_hd_t sha_headers; |
| 1634 | #elif defined(SHA_POLARSSL) |
| 1635 | sha1_context sha1_headers; |
| 1636 | sha2_context sha2_headers; |
| 1637 | #endif |
| 1638 | |
| 1639 | char *sig_hdr; |
| 1640 | char headerhash[32]; |
| 1641 | |
| 1642 | #ifdef RSA_GNUTLS |
| 1643 | uschar * hdata = NULL; |
| 1644 | int hdata_alloc = 0; |
| 1645 | int hdata_size = 0; |
| 1646 | #endif |
| 1647 | |
| 1648 | #ifdef SHA_GNUTLS |
| 1649 | gnutls_hash_init(&sha_headers, |
| 1650 | sig->algo == PDKIM_ALGO_RSA_SHA1 ? GNUTLS_DIG_SHA1 : GNUTLS_DIG_SHA256); |
| 1651 | #else |
| 1652 | if (sig->algo == PDKIM_ALGO_RSA_SHA1) |
| 1653 | # ifdef SHA_OPENSSL |
| 1654 | SHA1_Init(&sha1_headers); |
| 1655 | else |
| 1656 | SHA256_Init(&sha2_headers); |
| 1657 | # elif defined(SHA_POLARSSL) |
| 1658 | sha1_starts(&sha1_headers); |
| 1659 | else |
| 1660 | sha2_starts(&sha2_headers, 0); |
| 1661 | # endif |
| 1662 | #endif |
| 1663 | |
| 1664 | DEBUG(D_acl) debug_printf( |
| 1665 | "PDKIM >> Hashed header data, canonicalized, in sequence >>>>>>>>>>>>>>\n"); |
| 1666 | |
| 1667 | /* SIGNING ---------------------------------------------------------------- */ |
| 1668 | /* When signing, walk through our header list and add them to the hash. As we |
| 1669 | go, construct a list of the header's names to use for the h= parameter. */ |
| 1670 | |
| 1671 | if (ctx->mode == PDKIM_MODE_SIGN) |
| 1672 | { |
| 1673 | pdkim_stringlist *p; |
| 1674 | |
| 1675 | for (p = sig->headers; p; p = p->next) |
| 1676 | { |
| 1677 | char *rh = NULL; |
| 1678 | /* Collect header names (Note: colon presence is guaranteed here) */ |
| 1679 | char *q = strchr(p->value, ':'); |
| 1680 | |
| 1681 | if (!(pdkim_strncat(headernames, p->value, |
| 1682 | (q-(p->value)) + (p->next ? 1 : 0)))) |
| 1683 | return PDKIM_ERR_OOM; |
| 1684 | |
| 1685 | rh = sig->canon_headers == PDKIM_CANON_RELAXED |
| 1686 | ? pdkim_relax_header(p->value, 1) /* cook header for relaxed canon */ |
| 1687 | : strdup(p->value); /* just copy it for simple canon */ |
| 1688 | if (!rh) |
| 1689 | return PDKIM_ERR_OOM; |
| 1690 | |
| 1691 | /* Feed header to the hash algorithm */ |
| 1692 | #ifdef SHA_GNUTLS |
| 1693 | gnutls_hash(sha_headers, rh, strlen(rh)); |
| 1694 | #else |
| 1695 | if (sig->algo == PDKIM_ALGO_RSA_SHA1) |
| 1696 | # ifdef SHA_OPENSSL |
| 1697 | SHA1_Update (&sha1_headers, rh, strlen(rh)); |
| 1698 | else |
| 1699 | SHA256_Update(&sha2_headers, rh, strlen(rh)); |
| 1700 | # elif defined(SHA_POLARSSL) |
| 1701 | sha1_update(&sha1_headers, US rh, strlen(rh)); |
| 1702 | else |
| 1703 | sha2_update(&sha2_headers, US rh, strlen(rh)); |
| 1704 | # endif |
| 1705 | #endif |
| 1706 | |
| 1707 | #ifdef RSA_GNUTLS |
| 1708 | /* Remember headers block for signing */ |
| 1709 | hdata = string_append(hdata, &hdata_alloc, &hdata_size, 1, rh); |
| 1710 | #endif |
| 1711 | |
| 1712 | DEBUG(D_acl) pdkim_quoteprint(rh, strlen(rh), 1); |
| 1713 | free(rh); |
| 1714 | } |
| 1715 | } |
| 1716 | |
| 1717 | /* VERIFICATION ----------------------------------------------------------- */ |
| 1718 | /* When verifying, walk through the header name list in the h= parameter and |
| 1719 | add the headers to the hash in that order. */ |
| 1720 | else |
| 1721 | { |
| 1722 | char *b = strdup(sig->headernames); |
| 1723 | char *p = b; |
| 1724 | char *q = NULL; |
| 1725 | pdkim_stringlist *hdrs; |
| 1726 | |
| 1727 | if (!b) return PDKIM_ERR_OOM; |
| 1728 | |
| 1729 | /* clear tags */ |
| 1730 | for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next) |
| 1731 | hdrs->tag = 0; |
| 1732 | |
| 1733 | while(1) |
| 1734 | { |
| 1735 | if ((q = strchr(p, ':'))) |
| 1736 | *q = '\0'; |
| 1737 | |
| 1738 | for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next) |
| 1739 | if ( hdrs->tag == 0 |
| 1740 | && strncasecmp(hdrs->value, p, strlen(p)) == 0 |
| 1741 | && (hdrs->value)[strlen(p)] == ':' |
| 1742 | ) |
| 1743 | { |
| 1744 | char *rh; |
| 1745 | |
| 1746 | rh = sig->canon_headers == PDKIM_CANON_RELAXED |
| 1747 | ? pdkim_relax_header(hdrs->value, 1) /* cook header for relaxed canon */ |
| 1748 | : strdup(hdrs->value); /* just copy it for simple canon */ |
| 1749 | if (!rh) |
| 1750 | return PDKIM_ERR_OOM; |
| 1751 | |
| 1752 | /* Feed header to the hash algorithm */ |
| 1753 | #ifdef SHA_GNUTLS |
| 1754 | gnutls_hash(sha_headers, rh, strlen(rh)); |
| 1755 | #else |
| 1756 | if (sig->algo == PDKIM_ALGO_RSA_SHA1) |
| 1757 | # ifdef SHA_OPENSSL |
| 1758 | SHA1_Update (&sha1_headers, rh, strlen(rh)); |
| 1759 | else |
| 1760 | SHA256_Update(&sha2_headers, rh, strlen(rh)); |
| 1761 | # elif defined(SHA_POLARSSL) |
| 1762 | sha1_update(&sha1_headers, US rh, strlen(rh)); |
| 1763 | else |
| 1764 | sha2_update(&sha2_headers, US rh, strlen(rh)); |
| 1765 | # endif |
| 1766 | #endif |
| 1767 | |
| 1768 | DEBUG(D_acl) pdkim_quoteprint(rh, strlen(rh), 1); |
| 1769 | free(rh); |
| 1770 | hdrs->tag = 1; |
| 1771 | break; |
| 1772 | } |
| 1773 | |
| 1774 | if (!q) break; |
| 1775 | p = q+1; |
| 1776 | } |
| 1777 | free(b); |
| 1778 | } |
| 1779 | |
| 1780 | DEBUG(D_acl) debug_printf( |
| 1781 | "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); |
| 1782 | |
| 1783 | /* SIGNING ---------------------------------------------------------------- */ |
| 1784 | if (ctx->mode == PDKIM_MODE_SIGN) |
| 1785 | { |
| 1786 | /* Copy headernames to signature struct */ |
| 1787 | sig->headernames = strdup(headernames->str); |
| 1788 | pdkim_strfree(headernames); |
| 1789 | |
| 1790 | /* Create signature header with b= omitted */ |
| 1791 | sig_hdr = pdkim_create_header(ctx->sig, 0); |
| 1792 | } |
| 1793 | |
| 1794 | /* VERIFICATION ----------------------------------------------------------- */ |
| 1795 | else |
| 1796 | sig_hdr = strdup(sig->rawsig_no_b_val); |
| 1797 | /* ------------------------------------------------------------------------ */ |
| 1798 | |
| 1799 | if (!sig_hdr) |
| 1800 | return PDKIM_ERR_OOM; |
| 1801 | |
| 1802 | /* Relax header if necessary */ |
| 1803 | if (sig->canon_headers == PDKIM_CANON_RELAXED) |
| 1804 | { |
| 1805 | char *relaxed_hdr = pdkim_relax_header(sig_hdr, 0); |
| 1806 | |
| 1807 | free(sig_hdr); |
| 1808 | if (!relaxed_hdr) |
| 1809 | return PDKIM_ERR_OOM; |
| 1810 | sig_hdr = relaxed_hdr; |
| 1811 | } |
| 1812 | |
| 1813 | DEBUG(D_acl) |
| 1814 | { |
| 1815 | debug_printf( |
| 1816 | "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n"); |
| 1817 | pdkim_quoteprint(sig_hdr, strlen(sig_hdr), 1); |
| 1818 | debug_printf( |
| 1819 | "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); |
| 1820 | } |
| 1821 | |
| 1822 | /* Finalize header hash */ |
| 1823 | #ifdef SHA_GNUTLS |
| 1824 | gnutls_hash(sha_headers, sig_hdr, strlen(sig_hdr)); |
| 1825 | gnutls_hash_output(sha_headers, headerhash); |
| 1826 | #else |
| 1827 | if (sig->algo == PDKIM_ALGO_RSA_SHA1) |
| 1828 | # ifdef SHA_OPENSSL |
| 1829 | { |
| 1830 | SHA1_Update(&sha1_headers, sig_hdr, strlen(sig_hdr)); |
| 1831 | SHA1_Final(US headerhash, &sha1_headers); |
| 1832 | } |
| 1833 | else |
| 1834 | { |
| 1835 | SHA256_Update(&sha2_headers, sig_hdr, strlen(sig_hdr)); |
| 1836 | SHA256_Final(US headerhash, &sha2_headers); |
| 1837 | } |
| 1838 | # elif defined(SHA_POLARSSL) |
| 1839 | { |
| 1840 | sha1_update(&sha1_headers, US sig_hdr, strlen(sig_hdr)); |
| 1841 | sha1_finish(&sha1_headers, US headerhash); |
| 1842 | } |
| 1843 | else |
| 1844 | { |
| 1845 | sha2_update(&sha2_headers, US sig_hdr, strlen(sig_hdr)); |
| 1846 | sha2_finish(&sha2_headers, US headerhash); |
| 1847 | } |
| 1848 | # endif |
| 1849 | #endif |
| 1850 | |
| 1851 | DEBUG(D_acl) |
| 1852 | { |
| 1853 | debug_printf("PDKIM [%s] hh computed: ", sig->domain); |
| 1854 | pdkim_hexprint(headerhash, sig->algo == PDKIM_ALGO_RSA_SHA1 ? 20:32, 1); |
| 1855 | } |
| 1856 | |
| 1857 | #ifdef RSA_GNUTLS |
| 1858 | if (ctx->mode == PDKIM_MODE_SIGN) |
| 1859 | hdata = string_append(hdata, &hdata_alloc, &hdata_size, 1, sig_hdr); |
| 1860 | #endif |
| 1861 | |
| 1862 | free(sig_hdr); |
| 1863 | |
| 1864 | /* SIGNING ---------------------------------------------------------------- */ |
| 1865 | if (ctx->mode == PDKIM_MODE_SIGN) |
| 1866 | { |
| 1867 | #ifdef RSA_OPENSSL |
| 1868 | RSA * rsa; |
| 1869 | uschar * p, * q; |
| 1870 | int len; |
| 1871 | #elif defined(RSA_GNUTLS) |
| 1872 | gnutls_x509_privkey_t rsa; |
| 1873 | gnutls_datum_t k; |
| 1874 | int rc; |
| 1875 | size_t sigsize; |
| 1876 | #endif |
| 1877 | |
| 1878 | /* Import private key */ |
| 1879 | #ifdef RSA_OPENSSL |
| 1880 | |
| 1881 | if ( !(p = Ustrstr(sig->rsa_privkey, "-----BEGIN RSA PRIVATE KEY-----")) |
| 1882 | || !(q = Ustrstr(p+=31, "-----END RSA PRIVATE KEY-----")) |
| 1883 | ) |
| 1884 | return PDKIM_ERR_RSA_PRIVKEY; |
| 1885 | *q = '\0'; |
| 1886 | if ( (len = b64decode(p, &p)) < 0 |
| 1887 | || !(rsa = d2i_RSAPrivateKey(NULL, CUSS &p, len)) |
| 1888 | ) |
| 1889 | /*XXX todo: get errstring from library */ |
| 1890 | return PDKIM_ERR_RSA_PRIVKEY; |
| 1891 | |
| 1892 | #elif defined(RSA_GNUTLS) |
| 1893 | |
| 1894 | k.data = sig->rsa_privkey; |
| 1895 | k.size = strlen(sig->rsa_privkey); |
| 1896 | if ( (rc = gnutls_x509_privkey_init(&rsa)) != GNUTLS_E_SUCCESS |
| 1897 | || (rc = gnutls_x509_privkey_import2(rsa, &k, |
| 1898 | GNUTLS_X509_FMT_PEM, NULL, GNUTLS_PKCS_PLAIN)) != GNUTLS_E_SUCCESS |
| 1899 | ) |
| 1900 | { |
| 1901 | DEBUG(D_acl) debug_printf("gnutls_x509_privkey_import2: %s\n", |
| 1902 | gnutls_strerror(rc)); |
| 1903 | return PDKIM_ERR_RSA_PRIVKEY; |
| 1904 | } |
| 1905 | |
| 1906 | #endif |
| 1907 | |
| 1908 | |
| 1909 | /* Allocate mem for signature */ |
| 1910 | #ifdef RSA_OPENSSL |
| 1911 | sig->sigdata = store_get(RSA_size(rsa)); |
| 1912 | #elif defined(RSA_GNUTLS) |
| 1913 | k.data = hdata; |
| 1914 | k.size = hdata_size; |
| 1915 | (void) gnutls_x509_privkey_sign_data(rsa, |
| 1916 | sig->algo == PDKIM_ALGO_RSA_SHA1 ? GNUTLS_DIG_SHA1 : GNUTLS_DIG_SHA256, |
| 1917 | 0, &k, NULL, &sigsize); |
| 1918 | sig->sigdata = store_get(sig->sigdata_len = sigsize); |
| 1919 | #endif |
| 1920 | |
| 1921 | /* Do signing */ |
| 1922 | #ifdef RSA_OPENSSL |
| 1923 | |
| 1924 | if (RSA_sign(sig->algo == PDKIM_ALGO_RSA_SHA1 ? NID_sha1 : NID_sha256, |
| 1925 | CUS headerhash, sig->algo == PDKIM_ALGO_RSA_SHA1 ? 20 : 32, |
| 1926 | US sig->sigdata, (unsigned int *)&sig->sigdata_len, |
| 1927 | rsa) != 1) |
| 1928 | return PDKIM_ERR_RSA_SIGNING; |
| 1929 | RSA_free(rsa); |
| 1930 | |
| 1931 | #elif defined(RSA_GNUTLS) |
| 1932 | |
| 1933 | if ((rc = gnutls_x509_privkey_sign_data(rsa, |
| 1934 | sig->algo == PDKIM_ALGO_RSA_SHA1 ? GNUTLS_DIG_SHA1 : GNUTLS_DIG_SHA256, |
| 1935 | 0, &k, sig->sigdata, &sigsize)) != GNUTLS_E_SUCCESS |
| 1936 | ) |
| 1937 | { |
| 1938 | DEBUG(D_acl) debug_printf("gnutls_x509_privkey_sign_data: %s\n", |
| 1939 | gnutls_strerror(rc)); |
| 1940 | return PDKIM_ERR_RSA_SIGNING; |
| 1941 | } |
| 1942 | gnutls_x509_privkey_deinit(rsa); |
| 1943 | |
| 1944 | #endif |
| 1945 | |
| 1946 | |
| 1947 | DEBUG(D_acl) |
| 1948 | { |
| 1949 | debug_printf( "PDKIM [%s] b computed: ", sig->domain); |
| 1950 | pdkim_hexprint(sig->sigdata, sig->sigdata_len, 1); |
| 1951 | } |
| 1952 | |
| 1953 | if (!(sig->signature_header = pdkim_create_header(ctx->sig, 1))) |
| 1954 | return PDKIM_ERR_OOM; |
| 1955 | } |
| 1956 | |
| 1957 | /* VERIFICATION ----------------------------------------------------------- */ |
| 1958 | else |
| 1959 | { |
| 1960 | #ifdef RSA_OPENSSL |
| 1961 | RSA * rsa; |
| 1962 | const unsigned char * p; |
| 1963 | #elif defined(RSA_GNUTLS) |
| 1964 | gnutls_pubkey_t rsa; |
| 1965 | gnutls_datum_t k, s; |
| 1966 | int rc; |
| 1967 | #endif |
| 1968 | char *dns_txt_name, *dns_txt_reply; |
| 1969 | |
| 1970 | #ifdef RSA_GNUTLS |
| 1971 | gnutls_pubkey_init(&rsa); |
| 1972 | #endif |
| 1973 | |
| 1974 | /* Fetch public key for signing domain, from DNS */ |
| 1975 | |
| 1976 | if (!(dns_txt_name = malloc(PDKIM_DNS_TXT_MAX_NAMELEN))) |
| 1977 | return PDKIM_ERR_OOM; |
| 1978 | |
| 1979 | if (!(dns_txt_reply = malloc(PDKIM_DNS_TXT_MAX_RECLEN))) |
| 1980 | { |
| 1981 | free(dns_txt_name); |
| 1982 | return PDKIM_ERR_OOM; |
| 1983 | } |
| 1984 | |
| 1985 | memset(dns_txt_reply, 0, PDKIM_DNS_TXT_MAX_RECLEN); |
| 1986 | memset(dns_txt_name , 0, PDKIM_DNS_TXT_MAX_NAMELEN); |
| 1987 | |
| 1988 | if (snprintf(dns_txt_name, PDKIM_DNS_TXT_MAX_NAMELEN, |
| 1989 | "%s._domainkey.%s.", |
| 1990 | sig->selector, sig->domain) >= PDKIM_DNS_TXT_MAX_NAMELEN) |
| 1991 | { |
| 1992 | sig->verify_status = PDKIM_VERIFY_INVALID; |
| 1993 | sig->verify_ext_status = PDKIM_VERIFY_INVALID_BUFFER_SIZE; |
| 1994 | goto NEXT_VERIFY; |
| 1995 | } |
| 1996 | |
| 1997 | if ( ctx->dns_txt_callback(dns_txt_name, dns_txt_reply) != PDKIM_OK |
| 1998 | || dns_txt_reply[0] == '\0') |
| 1999 | { |
| 2000 | sig->verify_status = PDKIM_VERIFY_INVALID; |
| 2001 | sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE; |
| 2002 | goto NEXT_VERIFY; |
| 2003 | } |
| 2004 | |
| 2005 | DEBUG(D_acl) |
| 2006 | { |
| 2007 | debug_printf( |
| 2008 | "PDKIM >> Parsing public key record >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n" |
| 2009 | " Raw record: "); |
| 2010 | pdkim_quoteprint(dns_txt_reply, strlen(dns_txt_reply), 1); |
| 2011 | } |
| 2012 | |
| 2013 | if (!(sig->pubkey = pdkim_parse_pubkey_record(ctx, dns_txt_reply))) |
| 2014 | { |
| 2015 | sig->verify_status = PDKIM_VERIFY_INVALID; |
| 2016 | sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_PARSING; |
| 2017 | |
| 2018 | DEBUG(D_acl) debug_printf( |
| 2019 | " Error while parsing public key record\n" |
| 2020 | "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); |
| 2021 | goto NEXT_VERIFY; |
| 2022 | } |
| 2023 | |
| 2024 | DEBUG(D_acl) debug_printf( |
| 2025 | "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); |
| 2026 | |
| 2027 | /* Import public key */ |
| 2028 | #ifdef RSA_OPENSSL |
| 2029 | |
| 2030 | p = CUS sig->pubkey->key; |
| 2031 | if (!(rsa = d2i_RSA_PUBKEY(NULL, &p, (long) sig->pubkey->key_len))) |
| 2032 | |
| 2033 | #elif defined(RSA_GNUTLS) |
| 2034 | |
| 2035 | k.data = sig->pubkey->key; |
| 2036 | k.size = sig->pubkey->key_len; |
| 2037 | if ((rc = gnutls_pubkey_import(rsa, &k, GNUTLS_X509_FMT_DER)) |
| 2038 | != GNUTLS_E_SUCCESS) |
| 2039 | |
| 2040 | #endif |
| 2041 | { |
| 2042 | DEBUG(D_acl) |
| 2043 | { |
| 2044 | #ifdef RSA_OPENSSL |
| 2045 | long e; |
| 2046 | ERR_load_crypto_strings(); /*XXX move to a startup routine */ |
| 2047 | while ((e = ERR_get_error())) |
| 2048 | debug_printf("Az: %.120s\n", ERR_error_string(e, NULL)); |
| 2049 | #elif defined(RSA_GNUTLS) |
| 2050 | debug_printf("gnutls_pubkey_import: %s\n", gnutls_strerror(rc)); |
| 2051 | #endif |
| 2052 | } |
| 2053 | |
| 2054 | sig->verify_status = PDKIM_VERIFY_INVALID; |
| 2055 | sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_PARSING; |
| 2056 | goto NEXT_VERIFY; |
| 2057 | } |
| 2058 | |
| 2059 | /* Check the signature */ |
| 2060 | #ifdef RSA_OPENSSL |
| 2061 | |
| 2062 | if (RSA_verify(sig->algo == PDKIM_ALGO_RSA_SHA1 ? NID_sha1 : NID_sha256, |
| 2063 | CUS headerhash, sig->algo == PDKIM_ALGO_RSA_SHA1 ? 20 : 32, |
| 2064 | US sig->sigdata, (unsigned int)sig->sigdata_len, |
| 2065 | rsa) != 1) |
| 2066 | |
| 2067 | #elif defined(RSA_GNUTLS) |
| 2068 | |
| 2069 | k.data = headerhash; |
| 2070 | k.size = sig->algo == PDKIM_ALGO_RSA_SHA1 ? 20 : 32; |
| 2071 | s.data = sig->sigdata; |
| 2072 | s.size = sig->sigdata_len; |
| 2073 | if ((rc = gnutls_pubkey_verify_hash2(rsa, |
| 2074 | sig->algo == PDKIM_ALGO_RSA_SHA1 |
| 2075 | ? GNUTLS_SIGN_RSA_SHA1 : GNUTLS_SIGN_RSA_SHA256, |
| 2076 | 0, &k, &s)) < 0) |
| 2077 | |
| 2078 | #endif |
| 2079 | { |
| 2080 | #if defined(RSA_GNUTLS) |
| 2081 | debug_printf("gnutls_pubkey_verify_hash2: %s\n", gnutls_strerror(rc)); |
| 2082 | #endif |
| 2083 | sig->verify_status = PDKIM_VERIFY_FAIL; |
| 2084 | sig->verify_ext_status = PDKIM_VERIFY_FAIL_MESSAGE; |
| 2085 | goto NEXT_VERIFY; |
| 2086 | } |
| 2087 | |
| 2088 | /* We have a winner! (if bodydhash was correct earlier) */ |
| 2089 | if (sig->verify_status == PDKIM_VERIFY_NONE) |
| 2090 | sig->verify_status = PDKIM_VERIFY_PASS; |
| 2091 | |
| 2092 | NEXT_VERIFY: |
| 2093 | |
| 2094 | DEBUG(D_acl) |
| 2095 | { |
| 2096 | debug_printf("PDKIM [%s] signature status: %s", |
| 2097 | sig->domain, pdkim_verify_status_str(sig->verify_status)); |
| 2098 | if (sig->verify_ext_status > 0) |
| 2099 | debug_printf(" (%s)\n", |
| 2100 | pdkim_verify_ext_status_str(sig->verify_ext_status)); |
| 2101 | else |
| 2102 | debug_printf("\n"); |
| 2103 | } |
| 2104 | |
| 2105 | #ifdef RSA_GNUTLS |
| 2106 | gnutls_pubkey_deinit(rsa); |
| 2107 | #endif |
| 2108 | free(dns_txt_name); |
| 2109 | free(dns_txt_reply); |
| 2110 | } |
| 2111 | |
| 2112 | sig = sig->next; |
| 2113 | } |
| 2114 | |
| 2115 | /* If requested, set return pointer to signature(s) */ |
| 2116 | if (return_signatures) |
| 2117 | *return_signatures = ctx->sig; |
| 2118 | |
| 2119 | return PDKIM_OK; |
| 2120 | } |
| 2121 | |
| 2122 | |
| 2123 | /* -------------------------------------------------------------------------- */ |
| 2124 | |
| 2125 | DLLEXPORT pdkim_ctx * |
| 2126 | pdkim_init_verify(int(*dns_txt_callback)(char *, char *)) |
| 2127 | { |
| 2128 | pdkim_ctx *ctx = malloc(sizeof(pdkim_ctx)); |
| 2129 | |
| 2130 | if (!ctx) |
| 2131 | return NULL; |
| 2132 | memset(ctx, 0, sizeof(pdkim_ctx)); |
| 2133 | |
| 2134 | if (!(ctx->linebuf = malloc(PDKIM_MAX_BODY_LINE_LEN))) |
| 2135 | { |
| 2136 | free(ctx); |
| 2137 | return NULL; |
| 2138 | } |
| 2139 | |
| 2140 | ctx->mode = PDKIM_MODE_VERIFY; |
| 2141 | ctx->dns_txt_callback = dns_txt_callback; |
| 2142 | |
| 2143 | return ctx; |
| 2144 | } |
| 2145 | |
| 2146 | |
| 2147 | /* -------------------------------------------------------------------------- */ |
| 2148 | |
| 2149 | DLLEXPORT pdkim_ctx * |
| 2150 | pdkim_init_sign(char *domain, char *selector, char *rsa_privkey, int algo) |
| 2151 | { |
| 2152 | pdkim_ctx *ctx; |
| 2153 | pdkim_signature *sig; |
| 2154 | |
| 2155 | if (!domain || !selector || !rsa_privkey) |
| 2156 | return NULL; |
| 2157 | |
| 2158 | if (!(ctx = malloc(sizeof(pdkim_ctx)))) |
| 2159 | return NULL; |
| 2160 | memset(ctx, 0, sizeof(pdkim_ctx)); |
| 2161 | |
| 2162 | if (!(ctx->linebuf = malloc(PDKIM_MAX_BODY_LINE_LEN))) |
| 2163 | { |
| 2164 | free(ctx); |
| 2165 | return NULL; |
| 2166 | } |
| 2167 | |
| 2168 | if (!(sig = malloc(sizeof(pdkim_signature)))) |
| 2169 | { |
| 2170 | free(ctx->linebuf); |
| 2171 | free(ctx); |
| 2172 | return NULL; |
| 2173 | } |
| 2174 | memset(sig, 0, sizeof(pdkim_signature)); |
| 2175 | |
| 2176 | sig->bodylength = -1; |
| 2177 | |
| 2178 | ctx->mode = PDKIM_MODE_SIGN; |
| 2179 | ctx->sig = sig; |
| 2180 | |
| 2181 | ctx->sig->domain = strdup(domain); |
| 2182 | ctx->sig->selector = strdup(selector); |
| 2183 | ctx->sig->rsa_privkey = strdup(rsa_privkey); |
| 2184 | ctx->sig->algo = algo; |
| 2185 | |
| 2186 | if (!ctx->sig->domain || !ctx->sig->selector || !ctx->sig->rsa_privkey) |
| 2187 | goto BAIL; |
| 2188 | |
| 2189 | #ifdef SHA_OPENSSL |
| 2190 | SHA1_Init (&ctx->sig->sha1_body); |
| 2191 | SHA256_Init(&ctx->sig->sha2_body); |
| 2192 | |
| 2193 | #elif defined(SHA_GNUTLS) |
| 2194 | gnutls_hash_init(&ctx->sig->sha_body, |
| 2195 | algo == PDKIM_ALGO_RSA_SHA1 ? GNUTLS_DIG_SHA1 : GNUTLS_DIG_SHA256); |
| 2196 | |
| 2197 | #elif defined(SHA_POLARSSL) |
| 2198 | if (!(ctx->sig->sha1_body = malloc(sizeof(sha1_context)))) |
| 2199 | goto BAIL; |
| 2200 | sha1_starts(ctx->sig->sha1_body); |
| 2201 | |
| 2202 | if (!(ctx->sig->sha2_body = malloc(sizeof(sha2_context)))) |
| 2203 | goto BAIL; |
| 2204 | sha2_starts(ctx->sig->sha2_body, 0); |
| 2205 | |
| 2206 | #endif |
| 2207 | |
| 2208 | return ctx; |
| 2209 | |
| 2210 | BAIL: |
| 2211 | pdkim_free_ctx(ctx); |
| 2212 | return NULL; |
| 2213 | } |
| 2214 | |
| 2215 | |
| 2216 | /* -------------------------------------------------------------------------- */ |
| 2217 | |
| 2218 | DLLEXPORT int |
| 2219 | pdkim_set_optional(pdkim_ctx *ctx, |
| 2220 | char *sign_headers, |
| 2221 | char *identity, |
| 2222 | int canon_headers, |
| 2223 | int canon_body, |
| 2224 | long bodylength, |
| 2225 | unsigned long created, |
| 2226 | unsigned long expires) |
| 2227 | { |
| 2228 | if (identity) |
| 2229 | if (!(ctx->sig->identity = strdup(identity))) |
| 2230 | return PDKIM_ERR_OOM; |
| 2231 | |
| 2232 | if (sign_headers) |
| 2233 | if (!(ctx->sig->sign_headers = strdup(sign_headers))) |
| 2234 | return PDKIM_ERR_OOM; |
| 2235 | |
| 2236 | ctx->sig->canon_headers = canon_headers; |
| 2237 | ctx->sig->canon_body = canon_body; |
| 2238 | ctx->sig->bodylength = bodylength; |
| 2239 | ctx->sig->created = created; |
| 2240 | ctx->sig->expires = expires; |
| 2241 | |
| 2242 | return PDKIM_OK; |
| 2243 | } |
| 2244 | |
| 2245 | |
| 2246 | #endif /*DISABLE_DKIM*/ |