asn_mime.c revision 331638
1/* asn_mime.c */ 2/* 3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 4 * project. 5 */ 6/* ==================================================================== 7 * Copyright (c) 1999-2018 The OpenSSL Project. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * 21 * 3. All advertising materials mentioning features or use of this 22 * software must display the following acknowledgment: 23 * "This product includes software developed by the OpenSSL Project 24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 25 * 26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27 * endorse or promote products derived from this software without 28 * prior written permission. For written permission, please contact 29 * licensing@OpenSSL.org. 30 * 31 * 5. Products derived from this software may not be called "OpenSSL" 32 * nor may "OpenSSL" appear in their names without prior written 33 * permission of the OpenSSL Project. 34 * 35 * 6. Redistributions of any form whatsoever must retain the following 36 * acknowledgment: 37 * "This product includes software developed by the OpenSSL Project 38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51 * OF THE POSSIBILITY OF SUCH DAMAGE. 52 * ==================================================================== 53 * 54 */ 55 56#include <stdio.h> 57#include <ctype.h> 58#include "cryptlib.h" 59#include <openssl/rand.h> 60#include <openssl/x509.h> 61#include <openssl/asn1.h> 62#include <openssl/asn1t.h> 63#include "asn1_locl.h" 64 65/* 66 * Generalised MIME like utilities for streaming ASN1. Although many have a 67 * PKCS7/CMS like flavour others are more general purpose. 68 */ 69 70/* 71 * MIME format structures Note that all are translated to lower case apart 72 * from parameter values. Quotes are stripped off 73 */ 74 75typedef struct { 76 char *param_name; /* Param name e.g. "micalg" */ 77 char *param_value; /* Param value e.g. "sha1" */ 78} MIME_PARAM; 79 80DECLARE_STACK_OF(MIME_PARAM) 81IMPLEMENT_STACK_OF(MIME_PARAM) 82 83typedef struct { 84 char *name; /* Name of line e.g. "content-type" */ 85 char *value; /* Value of line e.g. "text/plain" */ 86 STACK_OF(MIME_PARAM) *params; /* Zero or more parameters */ 87} MIME_HEADER; 88 89DECLARE_STACK_OF(MIME_HEADER) 90IMPLEMENT_STACK_OF(MIME_HEADER) 91 92static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags, 93 const ASN1_ITEM *it); 94static char *strip_ends(char *name); 95static char *strip_start(char *name); 96static char *strip_end(char *name); 97static MIME_HEADER *mime_hdr_new(char *name, char *value); 98static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value); 99static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio); 100static int mime_hdr_cmp(const MIME_HEADER *const *a, 101 const MIME_HEADER *const *b); 102static int mime_param_cmp(const MIME_PARAM *const *a, 103 const MIME_PARAM *const *b); 104static void mime_param_free(MIME_PARAM *param); 105static int mime_bound_check(char *line, int linelen, char *bound, int blen); 106static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret); 107static int strip_eol(char *linebuf, int *plen); 108static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name); 109static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name); 110static void mime_hdr_free(MIME_HEADER *hdr); 111 112#define MAX_SMLEN 1024 113#define mime_debug(x) /* x */ 114 115/* Output an ASN1 structure in BER format streaming if necessary */ 116 117int i2d_ASN1_bio_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags, 118 const ASN1_ITEM *it) 119{ 120 /* If streaming create stream BIO and copy all content through it */ 121 if (flags & SMIME_STREAM) { 122 BIO *bio, *tbio; 123 bio = BIO_new_NDEF(out, val, it); 124 if (!bio) { 125 ASN1err(ASN1_F_I2D_ASN1_BIO_STREAM, ERR_R_MALLOC_FAILURE); 126 return 0; 127 } 128 SMIME_crlf_copy(in, bio, flags); 129 (void)BIO_flush(bio); 130 /* Free up successive BIOs until we hit the old output BIO */ 131 do { 132 tbio = BIO_pop(bio); 133 BIO_free(bio); 134 bio = tbio; 135 } while (bio != out); 136 } 137 /* 138 * else just write out ASN1 structure which will have all content stored 139 * internally 140 */ 141 else 142 ASN1_item_i2d_bio(it, out, val); 143 return 1; 144} 145 146/* Base 64 read and write of ASN1 structure */ 147 148static int B64_write_ASN1(BIO *out, ASN1_VALUE *val, BIO *in, int flags, 149 const ASN1_ITEM *it) 150{ 151 BIO *b64; 152 int r; 153 b64 = BIO_new(BIO_f_base64()); 154 if (!b64) { 155 ASN1err(ASN1_F_B64_WRITE_ASN1, ERR_R_MALLOC_FAILURE); 156 return 0; 157 } 158 /* 159 * prepend the b64 BIO so all data is base64 encoded. 160 */ 161 out = BIO_push(b64, out); 162 r = i2d_ASN1_bio_stream(out, val, in, flags, it); 163 (void)BIO_flush(out); 164 BIO_pop(out); 165 BIO_free(b64); 166 return r; 167} 168 169/* Streaming ASN1 PEM write */ 170 171int PEM_write_bio_ASN1_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags, 172 const char *hdr, const ASN1_ITEM *it) 173{ 174 int r; 175 BIO_printf(out, "-----BEGIN %s-----\n", hdr); 176 r = B64_write_ASN1(out, val, in, flags, it); 177 BIO_printf(out, "-----END %s-----\n", hdr); 178 return r; 179} 180 181static ASN1_VALUE *b64_read_asn1(BIO *bio, const ASN1_ITEM *it) 182{ 183 BIO *b64; 184 ASN1_VALUE *val; 185 if (!(b64 = BIO_new(BIO_f_base64()))) { 186 ASN1err(ASN1_F_B64_READ_ASN1, ERR_R_MALLOC_FAILURE); 187 return 0; 188 } 189 bio = BIO_push(b64, bio); 190 val = ASN1_item_d2i_bio(it, bio, NULL); 191 if (!val) 192 ASN1err(ASN1_F_B64_READ_ASN1, ASN1_R_DECODE_ERROR); 193 (void)BIO_flush(bio); 194 bio = BIO_pop(bio); 195 BIO_free(b64); 196 return val; 197} 198 199/* Generate the MIME "micalg" parameter from RFC3851, RFC4490 */ 200 201static int asn1_write_micalg(BIO *out, STACK_OF(X509_ALGOR) *mdalgs) 202{ 203 const EVP_MD *md; 204 int i, have_unknown = 0, write_comma, ret = 0, md_nid; 205 have_unknown = 0; 206 write_comma = 0; 207 for (i = 0; i < sk_X509_ALGOR_num(mdalgs); i++) { 208 if (write_comma) 209 BIO_write(out, ",", 1); 210 write_comma = 1; 211 md_nid = OBJ_obj2nid(sk_X509_ALGOR_value(mdalgs, i)->algorithm); 212 md = EVP_get_digestbynid(md_nid); 213 if (md && md->md_ctrl) { 214 int rv; 215 char *micstr; 216 rv = md->md_ctrl(NULL, EVP_MD_CTRL_MICALG, 0, &micstr); 217 if (rv > 0) { 218 BIO_puts(out, micstr); 219 OPENSSL_free(micstr); 220 continue; 221 } 222 if (rv != -2) 223 goto err; 224 } 225 switch (md_nid) { 226 case NID_sha1: 227 BIO_puts(out, "sha1"); 228 break; 229 230 case NID_md5: 231 BIO_puts(out, "md5"); 232 break; 233 234 case NID_sha256: 235 BIO_puts(out, "sha-256"); 236 break; 237 238 case NID_sha384: 239 BIO_puts(out, "sha-384"); 240 break; 241 242 case NID_sha512: 243 BIO_puts(out, "sha-512"); 244 break; 245 246 case NID_id_GostR3411_94: 247 BIO_puts(out, "gostr3411-94"); 248 goto err; 249 break; 250 251 default: 252 if (have_unknown) 253 write_comma = 0; 254 else { 255 BIO_puts(out, "unknown"); 256 have_unknown = 1; 257 } 258 break; 259 260 } 261 } 262 263 ret = 1; 264 err: 265 266 return ret; 267 268} 269 270/* SMIME sender */ 271 272int SMIME_write_ASN1(BIO *bio, ASN1_VALUE *val, BIO *data, int flags, 273 int ctype_nid, int econt_nid, 274 STACK_OF(X509_ALGOR) *mdalgs, const ASN1_ITEM *it) 275{ 276 char bound[33], c; 277 int i; 278 const char *mime_prefix, *mime_eol, *cname = "smime.p7m"; 279 const char *msg_type = NULL; 280 if (flags & SMIME_OLDMIME) 281 mime_prefix = "application/x-pkcs7-"; 282 else 283 mime_prefix = "application/pkcs7-"; 284 285 if (flags & SMIME_CRLFEOL) 286 mime_eol = "\r\n"; 287 else 288 mime_eol = "\n"; 289 if ((flags & SMIME_DETACHED) && data) { 290 /* We want multipart/signed */ 291 /* Generate a random boundary */ 292 if (RAND_bytes((unsigned char *)bound, 32) <= 0) 293 return 0; 294 for (i = 0; i < 32; i++) { 295 c = bound[i] & 0xf; 296 if (c < 10) 297 c += '0'; 298 else 299 c += 'A' - 10; 300 bound[i] = c; 301 } 302 bound[32] = 0; 303 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol); 304 BIO_printf(bio, "Content-Type: multipart/signed;"); 305 BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix); 306 BIO_puts(bio, " micalg=\""); 307 asn1_write_micalg(bio, mdalgs); 308 BIO_printf(bio, "\"; boundary=\"----%s\"%s%s", 309 bound, mime_eol, mime_eol); 310 BIO_printf(bio, "This is an S/MIME signed message%s%s", 311 mime_eol, mime_eol); 312 /* Now write out the first part */ 313 BIO_printf(bio, "------%s%s", bound, mime_eol); 314 if (!asn1_output_data(bio, data, val, flags, it)) 315 return 0; 316 BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol); 317 318 /* Headers for signature */ 319 320 BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix); 321 BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol); 322 BIO_printf(bio, "Content-Transfer-Encoding: base64%s", mime_eol); 323 BIO_printf(bio, "Content-Disposition: attachment;"); 324 BIO_printf(bio, " filename=\"smime.p7s\"%s%s", mime_eol, mime_eol); 325 B64_write_ASN1(bio, val, NULL, 0, it); 326 BIO_printf(bio, "%s------%s--%s%s", mime_eol, bound, 327 mime_eol, mime_eol); 328 return 1; 329 } 330 331 /* Determine smime-type header */ 332 333 if (ctype_nid == NID_pkcs7_enveloped) 334 msg_type = "enveloped-data"; 335 else if (ctype_nid == NID_pkcs7_signed) { 336 if (econt_nid == NID_id_smime_ct_receipt) 337 msg_type = "signed-receipt"; 338 else if (sk_X509_ALGOR_num(mdalgs) >= 0) 339 msg_type = "signed-data"; 340 else 341 msg_type = "certs-only"; 342 } else if (ctype_nid == NID_id_smime_ct_compressedData) { 343 msg_type = "compressed-data"; 344 cname = "smime.p7z"; 345 } 346 /* MIME headers */ 347 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol); 348 BIO_printf(bio, "Content-Disposition: attachment;"); 349 BIO_printf(bio, " filename=\"%s\"%s", cname, mime_eol); 350 BIO_printf(bio, "Content-Type: %smime;", mime_prefix); 351 if (msg_type) 352 BIO_printf(bio, " smime-type=%s;", msg_type); 353 BIO_printf(bio, " name=\"%s\"%s", cname, mime_eol); 354 BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s", 355 mime_eol, mime_eol); 356 if (!B64_write_ASN1(bio, val, data, flags, it)) 357 return 0; 358 BIO_printf(bio, "%s", mime_eol); 359 return 1; 360} 361 362/* Handle output of ASN1 data */ 363 364static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags, 365 const ASN1_ITEM *it) 366{ 367 BIO *tmpbio; 368 const ASN1_AUX *aux = it->funcs; 369 ASN1_STREAM_ARG sarg; 370 int rv = 1; 371 372 /* 373 * If data is not deteched or resigning then the output BIO is already 374 * set up to finalise when it is written through. 375 */ 376 if (!(flags & SMIME_DETACHED) || (flags & PKCS7_REUSE_DIGEST)) { 377 SMIME_crlf_copy(data, out, flags); 378 return 1; 379 } 380 381 if (!aux || !aux->asn1_cb) { 382 ASN1err(ASN1_F_ASN1_OUTPUT_DATA, ASN1_R_STREAMING_NOT_SUPPORTED); 383 return 0; 384 } 385 386 sarg.out = out; 387 sarg.ndef_bio = NULL; 388 sarg.boundary = NULL; 389 390 /* Let ASN1 code prepend any needed BIOs */ 391 392 if (aux->asn1_cb(ASN1_OP_DETACHED_PRE, &val, it, &sarg) <= 0) 393 return 0; 394 395 /* Copy data across, passing through filter BIOs for processing */ 396 SMIME_crlf_copy(data, sarg.ndef_bio, flags); 397 398 /* Finalize structure */ 399 if (aux->asn1_cb(ASN1_OP_DETACHED_POST, &val, it, &sarg) <= 0) 400 rv = 0; 401 402 /* Now remove any digests prepended to the BIO */ 403 404 while (sarg.ndef_bio != out) { 405 tmpbio = BIO_pop(sarg.ndef_bio); 406 BIO_free(sarg.ndef_bio); 407 sarg.ndef_bio = tmpbio; 408 } 409 410 return rv; 411 412} 413 414/* 415 * SMIME reader: handle multipart/signed and opaque signing. in multipart 416 * case the content is placed in a memory BIO pointed to by "bcont". In 417 * opaque this is set to NULL 418 */ 419 420ASN1_VALUE *SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it) 421{ 422 BIO *asnin; 423 STACK_OF(MIME_HEADER) *headers = NULL; 424 STACK_OF(BIO) *parts = NULL; 425 MIME_HEADER *hdr; 426 MIME_PARAM *prm; 427 ASN1_VALUE *val; 428 int ret; 429 430 if (bcont) 431 *bcont = NULL; 432 433 if (!(headers = mime_parse_hdr(bio))) { 434 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_MIME_PARSE_ERROR); 435 return NULL; 436 } 437 438 if (!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) { 439 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 440 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_CONTENT_TYPE); 441 return NULL; 442 } 443 444 /* Handle multipart/signed */ 445 446 if (!strcmp(hdr->value, "multipart/signed")) { 447 /* Split into two parts */ 448 prm = mime_param_find(hdr, "boundary"); 449 if (!prm || !prm->param_value) { 450 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 451 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BOUNDARY); 452 return NULL; 453 } 454 ret = multi_split(bio, prm->param_value, &parts); 455 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 456 if (!ret || (sk_BIO_num(parts) != 2)) { 457 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BODY_FAILURE); 458 sk_BIO_pop_free(parts, BIO_vfree); 459 return NULL; 460 } 461 462 /* Parse the signature piece */ 463 asnin = sk_BIO_value(parts, 1); 464 465 if (!(headers = mime_parse_hdr(asnin))) { 466 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_MIME_SIG_PARSE_ERROR); 467 sk_BIO_pop_free(parts, BIO_vfree); 468 return NULL; 469 } 470 471 /* Get content type */ 472 473 if (!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) { 474 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 475 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_SIG_CONTENT_TYPE); 476 sk_BIO_pop_free(parts, BIO_vfree); 477 return NULL; 478 } 479 480 if (strcmp(hdr->value, "application/x-pkcs7-signature") && 481 strcmp(hdr->value, "application/pkcs7-signature")) { 482 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_SIG_INVALID_MIME_TYPE); 483 ERR_add_error_data(2, "type: ", hdr->value); 484 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 485 sk_BIO_pop_free(parts, BIO_vfree); 486 return NULL; 487 } 488 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 489 /* Read in ASN1 */ 490 if (!(val = b64_read_asn1(asnin, it))) { 491 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_ASN1_SIG_PARSE_ERROR); 492 sk_BIO_pop_free(parts, BIO_vfree); 493 return NULL; 494 } 495 496 if (bcont) { 497 *bcont = sk_BIO_value(parts, 0); 498 BIO_free(asnin); 499 sk_BIO_free(parts); 500 } else 501 sk_BIO_pop_free(parts, BIO_vfree); 502 return val; 503 } 504 505 /* OK, if not multipart/signed try opaque signature */ 506 507 if (strcmp(hdr->value, "application/x-pkcs7-mime") && 508 strcmp(hdr->value, "application/pkcs7-mime")) { 509 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_INVALID_MIME_TYPE); 510 ERR_add_error_data(2, "type: ", hdr->value); 511 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 512 return NULL; 513 } 514 515 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 516 517 if (!(val = b64_read_asn1(bio, it))) { 518 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_ASN1_PARSE_ERROR); 519 return NULL; 520 } 521 return val; 522 523} 524 525/* Copy text from one BIO to another making the output CRLF at EOL */ 526int SMIME_crlf_copy(BIO *in, BIO *out, int flags) 527{ 528 BIO *bf; 529 char eol; 530 int len; 531 char linebuf[MAX_SMLEN]; 532 /* 533 * Buffer output so we don't write one line at a time. This is useful 534 * when streaming as we don't end up with one OCTET STRING per line. 535 */ 536 bf = BIO_new(BIO_f_buffer()); 537 if (!bf) 538 return 0; 539 out = BIO_push(bf, out); 540 if (flags & SMIME_BINARY) { 541 while ((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0) 542 BIO_write(out, linebuf, len); 543 } else { 544 if (flags & SMIME_TEXT) 545 BIO_printf(out, "Content-Type: text/plain\r\n\r\n"); 546 while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) { 547 eol = strip_eol(linebuf, &len); 548 if (len) 549 BIO_write(out, linebuf, len); 550 if (eol) 551 BIO_write(out, "\r\n", 2); 552 } 553 } 554 (void)BIO_flush(out); 555 BIO_pop(out); 556 BIO_free(bf); 557 return 1; 558} 559 560/* Strip off headers if they are text/plain */ 561int SMIME_text(BIO *in, BIO *out) 562{ 563 char iobuf[4096]; 564 int len; 565 STACK_OF(MIME_HEADER) *headers; 566 MIME_HEADER *hdr; 567 568 if (!(headers = mime_parse_hdr(in))) { 569 ASN1err(ASN1_F_SMIME_TEXT, ASN1_R_MIME_PARSE_ERROR); 570 return 0; 571 } 572 if (!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) { 573 ASN1err(ASN1_F_SMIME_TEXT, ASN1_R_MIME_NO_CONTENT_TYPE); 574 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 575 return 0; 576 } 577 if (strcmp(hdr->value, "text/plain")) { 578 ASN1err(ASN1_F_SMIME_TEXT, ASN1_R_INVALID_MIME_TYPE); 579 ERR_add_error_data(2, "type: ", hdr->value); 580 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 581 return 0; 582 } 583 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 584 while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0) 585 BIO_write(out, iobuf, len); 586 if (len < 0) 587 return 0; 588 return 1; 589} 590 591/* 592 * Split a multipart/XXX message body into component parts: result is 593 * canonical parts in a STACK of bios 594 */ 595 596static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret) 597{ 598 char linebuf[MAX_SMLEN]; 599 int len, blen; 600 int eol = 0, next_eol = 0; 601 BIO *bpart = NULL; 602 STACK_OF(BIO) *parts; 603 char state, part, first; 604 605 blen = strlen(bound); 606 part = 0; 607 state = 0; 608 first = 1; 609 parts = sk_BIO_new_null(); 610 *ret = parts; 611 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) { 612 state = mime_bound_check(linebuf, len, bound, blen); 613 if (state == 1) { 614 first = 1; 615 part++; 616 } else if (state == 2) { 617 sk_BIO_push(parts, bpart); 618 return 1; 619 } else if (part) { 620 /* Strip CR+LF from linebuf */ 621 next_eol = strip_eol(linebuf, &len); 622 if (first) { 623 first = 0; 624 if (bpart) 625 sk_BIO_push(parts, bpart); 626 bpart = BIO_new(BIO_s_mem()); 627 if (bpart == NULL) 628 return 1; 629 BIO_set_mem_eof_return(bpart, 0); 630 } else if (eol) 631 BIO_write(bpart, "\r\n", 2); 632 eol = next_eol; 633 if (len) 634 BIO_write(bpart, linebuf, len); 635 } 636 } 637 return 0; 638} 639 640/* This is the big one: parse MIME header lines up to message body */ 641 642#define MIME_INVALID 0 643#define MIME_START 1 644#define MIME_TYPE 2 645#define MIME_NAME 3 646#define MIME_VALUE 4 647#define MIME_QUOTE 5 648#define MIME_COMMENT 6 649 650static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio) 651{ 652 char *p, *q, c; 653 char *ntmp; 654 char linebuf[MAX_SMLEN]; 655 MIME_HEADER *mhdr = NULL; 656 STACK_OF(MIME_HEADER) *headers; 657 int len, state, save_state = 0; 658 659 headers = sk_MIME_HEADER_new(mime_hdr_cmp); 660 if (!headers) 661 return NULL; 662 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) { 663 /* If whitespace at line start then continuation line */ 664 if (mhdr && isspace((unsigned char)linebuf[0])) 665 state = MIME_NAME; 666 else 667 state = MIME_START; 668 ntmp = NULL; 669 /* Go through all characters */ 670 for (p = linebuf, q = linebuf; (c = *p) && (c != '\r') && (c != '\n'); 671 p++) { 672 673 /* 674 * State machine to handle MIME headers if this looks horrible 675 * that's because it *is* 676 */ 677 678 switch (state) { 679 case MIME_START: 680 if (c == ':') { 681 state = MIME_TYPE; 682 *p = 0; 683 ntmp = strip_ends(q); 684 q = p + 1; 685 } 686 break; 687 688 case MIME_TYPE: 689 if (c == ';') { 690 mime_debug("Found End Value\n"); 691 *p = 0; 692 mhdr = mime_hdr_new(ntmp, strip_ends(q)); 693 sk_MIME_HEADER_push(headers, mhdr); 694 ntmp = NULL; 695 q = p + 1; 696 state = MIME_NAME; 697 } else if (c == '(') { 698 save_state = state; 699 state = MIME_COMMENT; 700 } 701 break; 702 703 case MIME_COMMENT: 704 if (c == ')') { 705 state = save_state; 706 } 707 break; 708 709 case MIME_NAME: 710 if (c == '=') { 711 state = MIME_VALUE; 712 *p = 0; 713 ntmp = strip_ends(q); 714 q = p + 1; 715 } 716 break; 717 718 case MIME_VALUE: 719 if (c == ';') { 720 state = MIME_NAME; 721 *p = 0; 722 mime_hdr_addparam(mhdr, ntmp, strip_ends(q)); 723 ntmp = NULL; 724 q = p + 1; 725 } else if (c == '"') { 726 mime_debug("Found Quote\n"); 727 state = MIME_QUOTE; 728 } else if (c == '(') { 729 save_state = state; 730 state = MIME_COMMENT; 731 } 732 break; 733 734 case MIME_QUOTE: 735 if (c == '"') { 736 mime_debug("Found Match Quote\n"); 737 state = MIME_VALUE; 738 } 739 break; 740 } 741 } 742 743 if (state == MIME_TYPE) { 744 mhdr = mime_hdr_new(ntmp, strip_ends(q)); 745 sk_MIME_HEADER_push(headers, mhdr); 746 } else if (state == MIME_VALUE) 747 mime_hdr_addparam(mhdr, ntmp, strip_ends(q)); 748 if (p == linebuf) 749 break; /* Blank line means end of headers */ 750 } 751 752 return headers; 753 754} 755 756static char *strip_ends(char *name) 757{ 758 return strip_end(strip_start(name)); 759} 760 761/* Strip a parameter of whitespace from start of param */ 762static char *strip_start(char *name) 763{ 764 char *p, c; 765 /* Look for first non white space or quote */ 766 for (p = name; (c = *p); p++) { 767 if (c == '"') { 768 /* Next char is start of string if non null */ 769 if (p[1]) 770 return p + 1; 771 /* Else null string */ 772 return NULL; 773 } 774 if (!isspace((unsigned char)c)) 775 return p; 776 } 777 return NULL; 778} 779 780/* As above but strip from end of string : maybe should handle brackets? */ 781static char *strip_end(char *name) 782{ 783 char *p, c; 784 if (!name) 785 return NULL; 786 /* Look for first non white space or quote */ 787 for (p = name + strlen(name) - 1; p >= name; p--) { 788 c = *p; 789 if (c == '"') { 790 if (p - 1 == name) 791 return NULL; 792 *p = 0; 793 return name; 794 } 795 if (isspace((unsigned char)c)) 796 *p = 0; 797 else 798 return name; 799 } 800 return NULL; 801} 802 803static MIME_HEADER *mime_hdr_new(char *name, char *value) 804{ 805 MIME_HEADER *mhdr; 806 char *tmpname, *tmpval, *p; 807 int c; 808 if (name) { 809 if (!(tmpname = BUF_strdup(name))) 810 return NULL; 811 for (p = tmpname; *p; p++) { 812 c = (unsigned char)*p; 813 if (isupper(c)) { 814 c = tolower(c); 815 *p = c; 816 } 817 } 818 } else 819 tmpname = NULL; 820 if (value) { 821 if (!(tmpval = BUF_strdup(value))) 822 return NULL; 823 for (p = tmpval; *p; p++) { 824 c = (unsigned char)*p; 825 if (isupper(c)) { 826 c = tolower(c); 827 *p = c; 828 } 829 } 830 } else 831 tmpval = NULL; 832 mhdr = (MIME_HEADER *)OPENSSL_malloc(sizeof(MIME_HEADER)); 833 if (!mhdr) 834 return NULL; 835 mhdr->name = tmpname; 836 mhdr->value = tmpval; 837 if (!(mhdr->params = sk_MIME_PARAM_new(mime_param_cmp))) 838 return NULL; 839 return mhdr; 840} 841 842static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value) 843{ 844 char *tmpname, *tmpval, *p; 845 int c; 846 MIME_PARAM *mparam; 847 if (name) { 848 tmpname = BUF_strdup(name); 849 if (!tmpname) 850 return 0; 851 for (p = tmpname; *p; p++) { 852 c = (unsigned char)*p; 853 if (isupper(c)) { 854 c = tolower(c); 855 *p = c; 856 } 857 } 858 } else 859 tmpname = NULL; 860 if (value) { 861 tmpval = BUF_strdup(value); 862 if (!tmpval) 863 return 0; 864 } else 865 tmpval = NULL; 866 /* Parameter values are case sensitive so leave as is */ 867 mparam = (MIME_PARAM *)OPENSSL_malloc(sizeof(MIME_PARAM)); 868 if (!mparam) 869 return 0; 870 mparam->param_name = tmpname; 871 mparam->param_value = tmpval; 872 sk_MIME_PARAM_push(mhdr->params, mparam); 873 return 1; 874} 875 876static int mime_hdr_cmp(const MIME_HEADER *const *a, 877 const MIME_HEADER *const *b) 878{ 879 if (!(*a)->name || !(*b)->name) 880 return ! !(*a)->name - ! !(*b)->name; 881 882 return (strcmp((*a)->name, (*b)->name)); 883} 884 885static int mime_param_cmp(const MIME_PARAM *const *a, 886 const MIME_PARAM *const *b) 887{ 888 if (!(*a)->param_name || !(*b)->param_name) 889 return ! !(*a)->param_name - ! !(*b)->param_name; 890 return (strcmp((*a)->param_name, (*b)->param_name)); 891} 892 893/* Find a header with a given name (if possible) */ 894 895static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name) 896{ 897 MIME_HEADER htmp; 898 int idx; 899 htmp.name = name; 900 idx = sk_MIME_HEADER_find(hdrs, &htmp); 901 if (idx < 0) 902 return NULL; 903 return sk_MIME_HEADER_value(hdrs, idx); 904} 905 906static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name) 907{ 908 MIME_PARAM param; 909 int idx; 910 param.param_name = name; 911 idx = sk_MIME_PARAM_find(hdr->params, ¶m); 912 if (idx < 0) 913 return NULL; 914 return sk_MIME_PARAM_value(hdr->params, idx); 915} 916 917static void mime_hdr_free(MIME_HEADER *hdr) 918{ 919 if (hdr->name) 920 OPENSSL_free(hdr->name); 921 if (hdr->value) 922 OPENSSL_free(hdr->value); 923 if (hdr->params) 924 sk_MIME_PARAM_pop_free(hdr->params, mime_param_free); 925 OPENSSL_free(hdr); 926} 927 928static void mime_param_free(MIME_PARAM *param) 929{ 930 if (param->param_name) 931 OPENSSL_free(param->param_name); 932 if (param->param_value) 933 OPENSSL_free(param->param_value); 934 OPENSSL_free(param); 935} 936 937/*- 938 * Check for a multipart boundary. Returns: 939 * 0 : no boundary 940 * 1 : part boundary 941 * 2 : final boundary 942 */ 943static int mime_bound_check(char *line, int linelen, char *bound, int blen) 944{ 945 if (linelen == -1) 946 linelen = strlen(line); 947 if (blen == -1) 948 blen = strlen(bound); 949 /* Quickly eliminate if line length too short */ 950 if (blen + 2 > linelen) 951 return 0; 952 /* Check for part boundary */ 953 if (!strncmp(line, "--", 2) && !strncmp(line + 2, bound, blen)) { 954 if (!strncmp(line + blen + 2, "--", 2)) 955 return 2; 956 else 957 return 1; 958 } 959 return 0; 960} 961 962static int strip_eol(char *linebuf, int *plen) 963{ 964 int len = *plen; 965 char *p, c; 966 int is_eol = 0; 967 p = linebuf + len - 1; 968 for (p = linebuf + len - 1; len > 0; len--, p--) { 969 c = *p; 970 if (c == '\n') 971 is_eol = 1; 972 else if (c != '\r') 973 break; 974 } 975 *plen = len; 976 return is_eol; 977} 978