1 /* asn_mime.c */ 2 /* Written by Dr Stephen N Henson (steve (at) openssl.org) for the OpenSSL 3 * project. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 1999-2008 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * licensing (at) OpenSSL.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 */ 54 55 #include <stdio.h> 56 #include <ctype.h> 57 #include "cryptlib.h" 58 #include <openssl/rand.h> 59 #include <openssl/x509.h> 60 #include <openssl/asn1.h> 61 #include <openssl/asn1t.h> 62 #include "asn1_locl.h" 63 64 /* Generalised MIME like utilities for streaming ASN1. Although many 65 * have a PKCS7/CMS like flavour others are more general purpose. 66 */ 67 68 /* MIME format structures 69 * Note that all are translated to lower case apart from 70 * parameter values. Quotes are stripped off 71 */ 72 73 typedef struct { 74 char *param_name; /* Param name e.g. "micalg" */ 75 char *param_value; /* Param value e.g. "sha1" */ 76 } MIME_PARAM; 77 78 DECLARE_STACK_OF(MIME_PARAM) 79 IMPLEMENT_STACK_OF(MIME_PARAM) 80 81 typedef struct { 82 char *name; /* Name of line e.g. "content-type" */ 83 char *value; /* Value of line e.g. "text/plain" */ 84 STACK_OF(MIME_PARAM) *params; /* Zero or more parameters */ 85 } MIME_HEADER; 86 87 DECLARE_STACK_OF(MIME_HEADER) 88 IMPLEMENT_STACK_OF(MIME_HEADER) 89 90 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags, 91 const ASN1_ITEM *it); 92 static char * strip_ends(char *name); 93 static char * strip_start(char *name); 94 static char * strip_end(char *name); 95 static MIME_HEADER *mime_hdr_new(char *name, char *value); 96 static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value); 97 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio); 98 static int mime_hdr_cmp(const MIME_HEADER * const *a, 99 const MIME_HEADER * const *b); 100 static int mime_param_cmp(const MIME_PARAM * const *a, 101 const MIME_PARAM * const *b); 102 static void mime_param_free(MIME_PARAM *param); 103 static int mime_bound_check(char *line, int linelen, char *bound, int blen); 104 static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret); 105 static int strip_eol(char *linebuf, int *plen); 106 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name); 107 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name); 108 static void mime_hdr_free(MIME_HEADER *hdr); 109 110 #define MAX_SMLEN 1024 111 #define mime_debug(x) /* x */ 112 113 /* Output an ASN1 structure in BER format streaming if necessary */ 114 115 int i2d_ASN1_bio_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags, 116 const ASN1_ITEM *it) 117 { 118 /* If streaming create stream BIO and copy all content through it */ 119 if (flags & SMIME_STREAM) 120 { 121 BIO *bio, *tbio; 122 bio = BIO_new_NDEF(out, val, it); 123 if (!bio) 124 { 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 { 133 tbio = BIO_pop(bio); 134 BIO_free(bio); 135 bio = tbio; 136 } while (bio != out); 137 } 138 /* else just write out ASN1 structure which will have all content 139 * stored 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 */ 147 148 static 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 { 156 ASN1err(ASN1_F_B64_WRITE_ASN1,ERR_R_MALLOC_FAILURE); 157 return 0; 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 */ 170 171 int PEM_write_bio_ASN1_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags, 172 const char *hdr, 173 const ASN1_ITEM *it) 174 { 175 int r; 176 BIO_printf(out, "-----BEGIN %s-----\n", hdr); 177 r = B64_write_ASN1(out, val, in, flags, it); 178 BIO_printf(out, "-----END %s-----\n", hdr); 179 return r; 180 } 181 182 static ASN1_VALUE *b64_read_asn1(BIO *bio, const ASN1_ITEM *it) 183 { 184 BIO *b64; 185 ASN1_VALUE *val; 186 if(!(b64 = BIO_new(BIO_f_base64()))) { 187 ASN1err(ASN1_F_B64_READ_ASN1,ERR_R_MALLOC_FAILURE); 188 return 0; 189 } 190 bio = BIO_push(b64, bio); 191 val = ASN1_item_d2i_bio(it, bio, NULL); 192 if(!val) 193 ASN1err(ASN1_F_B64_READ_ASN1,ASN1_R_DECODE_ERROR); 194 (void)BIO_flush(bio); 195 bio = BIO_pop(bio); 196 BIO_free(b64); 197 return val; 198 } 199 200 /* Generate the MIME "micalg" parameter from RFC3851, RFC4490 */ 201 202 static int asn1_write_micalg(BIO *out, STACK_OF(X509_ALGOR) *mdalgs) 203 { 204 const EVP_MD *md; 205 int i, have_unknown = 0, write_comma, ret = 0, md_nid; 206 have_unknown = 0; 207 write_comma = 0; 208 for (i = 0; i < sk_X509_ALGOR_num(mdalgs); i++) 209 { 210 if (write_comma) 211 BIO_write(out, ",", 1); 212 write_comma = 1; 213 md_nid = OBJ_obj2nid(sk_X509_ALGOR_value(mdalgs, i)->algorithm); 214 md = EVP_get_digestbynid(md_nid); 215 if (md && md->md_ctrl) 216 { 217 int rv; 218 char *micstr; 219 rv = md->md_ctrl(NULL, EVP_MD_CTRL_MICALG, 0, &micstr); 220 if (rv > 0) 221 { 222 BIO_puts(out, micstr); 223 OPENSSL_free(micstr); 224 continue; 225 } 226 if (rv != -2) 227 goto err; 228 } 229 switch(md_nid) 230 { 231 case NID_sha1: 232 BIO_puts(out, "sha1"); 233 break; 234 235 case NID_md5: 236 BIO_puts(out, "md5"); 237 break; 238 239 case NID_sha256: 240 BIO_puts(out, "sha-256"); 241 break; 242 243 case NID_sha384: 244 BIO_puts(out, "sha-384"); 245 break; 246 247 case NID_sha512: 248 BIO_puts(out, "sha-512"); 249 break; 250 251 case NID_id_GostR3411_94: 252 BIO_puts(out, "gostr3411-94"); 253 goto err; 254 break; 255 256 default: 257 if (have_unknown) 258 write_comma = 0; 259 else 260 { 261 BIO_puts(out, "unknown"); 262 have_unknown = 1; 263 } 264 break; 265 266 } 267 } 268 269 ret = 1; 270 err: 271 272 return ret; 273 274 } 275 276 /* SMIME sender */ 277 278 int SMIME_write_ASN1(BIO *bio, ASN1_VALUE *val, BIO *data, int flags, 279 int ctype_nid, int econt_nid, 280 STACK_OF(X509_ALGOR) *mdalgs, 281 const ASN1_ITEM *it) 282 { 283 char bound[33], c; 284 int i; 285 const char *mime_prefix, *mime_eol, *cname = "smime.p7m"; 286 const char *msg_type=NULL; 287 if (flags & SMIME_OLDMIME) 288 mime_prefix = "application/x-pkcs7-"; 289 else 290 mime_prefix = "application/pkcs7-"; 291 292 if (flags & SMIME_CRLFEOL) 293 mime_eol = "\r\n"; 294 else 295 mime_eol = "\n"; 296 if((flags & SMIME_DETACHED) && data) { 297 /* We want multipart/signed */ 298 /* Generate a random boundary */ 299 RAND_pseudo_bytes((unsigned char *)bound, 32); 300 for(i = 0; i < 32; i++) { 301 c = bound[i] & 0xf; 302 if(c < 10) c += '0'; 303 else c += 'A' - 10; 304 bound[i] = c; 305 } 306 bound[32] = 0; 307 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol); 308 BIO_printf(bio, "Content-Type: multipart/signed;"); 309 BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix); 310 BIO_puts(bio, " micalg=\""); 311 asn1_write_micalg(bio, mdalgs); 312 BIO_printf(bio, "\"; boundary=\"----%s\"%s%s", 313 bound, mime_eol, mime_eol); 314 BIO_printf(bio, "This is an S/MIME signed message%s%s", 315 mime_eol, mime_eol); 316 /* Now write out the first part */ 317 BIO_printf(bio, "------%s%s", bound, mime_eol); 318 if (!asn1_output_data(bio, data, val, flags, it)) 319 return 0; 320 BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol); 321 322 /* Headers for signature */ 323 324 BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix); 325 BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol); 326 BIO_printf(bio, "Content-Transfer-Encoding: base64%s", 327 mime_eol); 328 BIO_printf(bio, "Content-Disposition: attachment;"); 329 BIO_printf(bio, " filename=\"smime.p7s\"%s%s", 330 mime_eol, mime_eol); 331 B64_write_ASN1(bio, val, NULL, 0, it); 332 BIO_printf(bio,"%s------%s--%s%s", mime_eol, bound, 333 mime_eol, mime_eol); 334 return 1; 335 } 336 337 /* Determine smime-type header */ 338 339 if (ctype_nid == NID_pkcs7_enveloped) 340 msg_type = "enveloped-data"; 341 else if (ctype_nid == NID_pkcs7_signed) 342 { 343 if (econt_nid == NID_id_smime_ct_receipt) 344 msg_type = "signed-receipt"; 345 else if (sk_X509_ALGOR_num(mdalgs) >= 0) 346 msg_type = "signed-data"; 347 else 348 msg_type = "certs-only"; 349 } 350 else if (ctype_nid == NID_id_smime_ct_compressedData) 351 { 352 msg_type = "compressed-data"; 353 cname = "smime.p7z"; 354 } 355 /* MIME headers */ 356 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol); 357 BIO_printf(bio, "Content-Disposition: attachment;"); 358 BIO_printf(bio, " filename=\"%s\"%s", cname, mime_eol); 359 BIO_printf(bio, "Content-Type: %smime;", mime_prefix); 360 if (msg_type) 361 BIO_printf(bio, " smime-type=%s;", msg_type); 362 BIO_printf(bio, " name=\"%s\"%s", cname, mime_eol); 363 BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s", 364 mime_eol, mime_eol); 365 if (!B64_write_ASN1(bio, val, data, flags, it)) 366 return 0; 367 BIO_printf(bio, "%s", mime_eol); 368 return 1; 369 } 370 371 /* Handle output of ASN1 data */ 372 373 374 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags, 375 const ASN1_ITEM *it) 376 { 377 BIO *tmpbio; 378 const ASN1_AUX *aux = it->funcs; 379 ASN1_STREAM_ARG sarg; 380 381 if (!(flags & SMIME_DETACHED)) 382 { 383 SMIME_crlf_copy(data, out, flags); 384 return 1; 385 } 386 387 if (!aux || !aux->asn1_cb) 388 { 389 ASN1err(ASN1_F_ASN1_OUTPUT_DATA, 390 ASN1_R_STREAMING_NOT_SUPPORTED); 391 return 0; 392 } 393 394 sarg.out = out; 395 sarg.ndef_bio = NULL; 396 sarg.boundary = NULL; 397 398 /* Let ASN1 code prepend any needed BIOs */ 399 400 if (aux->asn1_cb(ASN1_OP_DETACHED_PRE, &val, it, &sarg) <= 0) 401 return 0; 402 403 /* Copy data across, passing through filter BIOs for processing */ 404 SMIME_crlf_copy(data, sarg.ndef_bio, flags); 405 406 /* Finalize structure */ 407 if (aux->asn1_cb(ASN1_OP_DETACHED_POST, &val, it, &sarg) <= 0) 408 return 0; 409 410 /* Now remove any digests prepended to the BIO */ 411 412 while (sarg.ndef_bio != out) 413 { 414 tmpbio = BIO_pop(sarg.ndef_bio); 415 BIO_free(sarg.ndef_bio); 416 sarg.ndef_bio = tmpbio; 417 } 418 419 return 1; 420 421 } 422 423 /* SMIME reader: handle multipart/signed and opaque signing. 424 * in multipart case the content is placed in a memory BIO 425 * pointed to by "bcont". In opaque this is set to NULL 426 */ 427 428 ASN1_VALUE *SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it) 429 { 430 BIO *asnin; 431 STACK_OF(MIME_HEADER) *headers = NULL; 432 STACK_OF(BIO) *parts = NULL; 433 MIME_HEADER *hdr; 434 MIME_PARAM *prm; 435 ASN1_VALUE *val; 436 int ret; 437 438 if(bcont) *bcont = NULL; 439 440 if (!(headers = mime_parse_hdr(bio))) { 441 ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_MIME_PARSE_ERROR); 442 return NULL; 443 } 444 445 if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) { 446 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 447 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_CONTENT_TYPE); 448 return NULL; 449 } 450 451 /* Handle multipart/signed */ 452 453 if(!strcmp(hdr->value, "multipart/signed")) { 454 /* Split into two parts */ 455 prm = mime_param_find(hdr, "boundary"); 456 if(!prm || !prm->param_value) { 457 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 458 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BOUNDARY); 459 return NULL; 460 } 461 ret = multi_split(bio, prm->param_value, &parts); 462 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 463 if(!ret || (sk_BIO_num(parts) != 2) ) { 464 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BODY_FAILURE); 465 sk_BIO_pop_free(parts, BIO_vfree); 466 return NULL; 467 } 468 469 /* Parse the signature piece */ 470 asnin = sk_BIO_value(parts, 1); 471 472 if (!(headers = mime_parse_hdr(asnin))) { 473 ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_MIME_SIG_PARSE_ERROR); 474 sk_BIO_pop_free(parts, BIO_vfree); 475 return NULL; 476 } 477 478 /* Get content type */ 479 480 if(!(hdr = mime_hdr_find(headers, "content-type")) || 481 !hdr->value) { 482 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 483 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_SIG_CONTENT_TYPE); 484 return NULL; 485 } 486 487 if(strcmp(hdr->value, "application/x-pkcs7-signature") && 488 strcmp(hdr->value, "application/pkcs7-signature")) { 489 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 490 ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_SIG_INVALID_MIME_TYPE); 491 ERR_add_error_data(2, "type: ", hdr->value); 492 sk_BIO_pop_free(parts, BIO_vfree); 493 return NULL; 494 } 495 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 496 /* Read in ASN1 */ 497 if(!(val = b64_read_asn1(asnin, it))) { 498 ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_ASN1_SIG_PARSE_ERROR); 499 sk_BIO_pop_free(parts, BIO_vfree); 500 return NULL; 501 } 502 503 if(bcont) { 504 *bcont = sk_BIO_value(parts, 0); 505 BIO_free(asnin); 506 sk_BIO_free(parts); 507 } else sk_BIO_pop_free(parts, BIO_vfree); 508 return val; 509 } 510 511 /* OK, if not multipart/signed try opaque signature */ 512 513 if (strcmp (hdr->value, "application/x-pkcs7-mime") && 514 strcmp (hdr->value, "application/pkcs7-mime")) { 515 ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_INVALID_MIME_TYPE); 516 ERR_add_error_data(2, "type: ", hdr->value); 517 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 518 return NULL; 519 } 520 521 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 522 523 if(!(val = b64_read_asn1(bio, it))) { 524 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_ASN1_PARSE_ERROR); 525 return NULL; 526 } 527 return val; 528 529 } 530 531 /* Copy text from one BIO to another making the output CRLF at EOL */ 532 int SMIME_crlf_copy(BIO *in, BIO *out, int flags) 533 { 534 BIO *bf; 535 char eol; 536 int len; 537 char linebuf[MAX_SMLEN]; 538 /* Buffer output so we don't write one line at a time. This is 539 * useful when streaming as we don't end up with one OCTET STRING 540 * per line. 541 */ 542 bf = BIO_new(BIO_f_buffer()); 543 if (!bf) 544 return 0; 545 out = BIO_push(bf, out); 546 if(flags & SMIME_BINARY) 547 { 548 while((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0) 549 BIO_write(out, linebuf, len); 550 } 551 else 552 { 553 if(flags & SMIME_TEXT) 554 BIO_printf(out, "Content-Type: text/plain\r\n\r\n"); 555 while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) 556 { 557 eol = strip_eol(linebuf, &len); 558 if (len) 559 BIO_write(out, linebuf, len); 560 if(eol) BIO_write(out, "\r\n", 2); 561 } 562 } 563 (void)BIO_flush(out); 564 BIO_pop(out); 565 BIO_free(bf); 566 return 1; 567 } 568 569 /* Strip off headers if they are text/plain */ 570 int SMIME_text(BIO *in, BIO *out) 571 { 572 char iobuf[4096]; 573 int len; 574 STACK_OF(MIME_HEADER) *headers; 575 MIME_HEADER *hdr; 576 577 if (!(headers = mime_parse_hdr(in))) { 578 ASN1err(ASN1_F_SMIME_TEXT,ASN1_R_MIME_PARSE_ERROR); 579 return 0; 580 } 581 if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) { 582 ASN1err(ASN1_F_SMIME_TEXT,ASN1_R_MIME_NO_CONTENT_TYPE); 583 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 584 return 0; 585 } 586 if (strcmp (hdr->value, "text/plain")) { 587 ASN1err(ASN1_F_SMIME_TEXT,ASN1_R_INVALID_MIME_TYPE); 588 ERR_add_error_data(2, "type: ", hdr->value); 589 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 590 return 0; 591 } 592 sk_MIME_HEADER_pop_free(headers, mime_hdr_free); 593 while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0) 594 BIO_write(out, iobuf, len); 595 if (len < 0) 596 return 0; 597 return 1; 598 } 599 600 /* Split a multipart/XXX message body into component parts: result is 601 * canonical parts in a STACK of bios 602 */ 603 604 static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret) 605 { 606 char linebuf[MAX_SMLEN]; 607 int len, blen; 608 int eol = 0, next_eol = 0; 609 BIO *bpart = NULL; 610 STACK_OF(BIO) *parts; 611 char state, part, first; 612 613 blen = strlen(bound); 614 part = 0; 615 state = 0; 616 first = 1; 617 parts = sk_BIO_new_null(); 618 *ret = parts; 619 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) { 620 state = mime_bound_check(linebuf, len, bound, blen); 621 if(state == 1) { 622 first = 1; 623 part++; 624 } else if(state == 2) { 625 sk_BIO_push(parts, bpart); 626 return 1; 627 } else if(part) { 628 /* Strip CR+LF from linebuf */ 629 next_eol = strip_eol(linebuf, &len); 630 if(first) { 631 first = 0; 632 if(bpart) sk_BIO_push(parts, bpart); 633 bpart = BIO_new(BIO_s_mem()); 634 BIO_set_mem_eof_return(bpart, 0); 635 } else if (eol) 636 BIO_write(bpart, "\r\n", 2); 637 eol = next_eol; 638 if (len) 639 BIO_write(bpart, linebuf, len); 640 } 641 } 642 return 0; 643 } 644 645 /* This is the big one: parse MIME header lines up to message body */ 646 647 #define MIME_INVALID 0 648 #define MIME_START 1 649 #define MIME_TYPE 2 650 #define MIME_NAME 3 651 #define MIME_VALUE 4 652 #define MIME_QUOTE 5 653 #define MIME_COMMENT 6 654 655 656 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio) 657 { 658 char *p, *q, c; 659 char *ntmp; 660 char linebuf[MAX_SMLEN]; 661 MIME_HEADER *mhdr = NULL; 662 STACK_OF(MIME_HEADER) *headers; 663 int len, state, save_state = 0; 664 665 headers = sk_MIME_HEADER_new(mime_hdr_cmp); 666 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) { 667 /* If whitespace at line start then continuation line */ 668 if(mhdr && isspace((unsigned char)linebuf[0])) state = MIME_NAME; 669 else state = MIME_START; 670 ntmp = NULL; 671 /* Go through all characters */ 672 for(p = linebuf, q = linebuf; (c = *p) && (c!='\r') && (c!='\n'); p++) { 673 674 /* State machine to handle MIME headers 675 * if this looks horrible 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) break; /* Blank line means end of headers */ 749 } 750 751 return headers; 752 753 } 754 755 static char *strip_ends(char *name) 756 { 757 return strip_end(strip_start(name)); 758 } 759 760 /* Strip a parameter of whitespace from start of param */ 761 static char *strip_start(char *name) 762 { 763 char *p, c; 764 /* Look for first non white space or quote */ 765 for(p = name; (c = *p) ;p++) { 766 if(c == '"') { 767 /* Next char is start of string if non null */ 768 if(p[1]) return p + 1; 769 /* Else null string */ 770 return NULL; 771 } 772 if(!isspace((unsigned char)c)) return p; 773 } 774 return NULL; 775 } 776 777 /* As above but strip from end of string : maybe should handle brackets? */ 778 static char *strip_end(char *name) 779 { 780 char *p, c; 781 if(!name) return NULL; 782 /* Look for first non white space or quote */ 783 for(p = name + strlen(name) - 1; p >= name ;p--) { 784 c = *p; 785 if(c == '"') { 786 if(p - 1 == name) return NULL; 787 *p = 0; 788 return name; 789 } 790 if(isspace((unsigned char)c)) *p = 0; 791 else return name; 792 } 793 return NULL; 794 } 795 796 static MIME_HEADER *mime_hdr_new(char *name, char *value) 797 { 798 MIME_HEADER *mhdr; 799 char *tmpname, *tmpval, *p; 800 int c; 801 if(name) { 802 if(!(tmpname = BUF_strdup(name))) return NULL; 803 for(p = tmpname ; *p; p++) { 804 c = *p; 805 if(isupper(c)) { 806 c = tolower(c); 807 *p = c; 808 } 809 } 810 } else tmpname = NULL; 811 if(value) { 812 if(!(tmpval = BUF_strdup(value))) return NULL; 813 for(p = tmpval ; *p; p++) { 814 c = *p; 815 if(isupper(c)) { 816 c = tolower(c); 817 *p = c; 818 } 819 } 820 } else tmpval = NULL; 821 mhdr = (MIME_HEADER *) OPENSSL_malloc(sizeof(MIME_HEADER)); 822 if(!mhdr) return NULL; 823 mhdr->name = tmpname; 824 mhdr->value = tmpval; 825 if(!(mhdr->params = sk_MIME_PARAM_new(mime_param_cmp))) return NULL; 826 return mhdr; 827 } 828 829 static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value) 830 { 831 char *tmpname, *tmpval, *p; 832 int c; 833 MIME_PARAM *mparam; 834 if(name) { 835 tmpname = BUF_strdup(name); 836 if(!tmpname) return 0; 837 for(p = tmpname ; *p; p++) { 838 c = *p; 839 if(isupper(c)) { 840 c = tolower(c); 841 *p = c; 842 } 843 } 844 } else tmpname = NULL; 845 if(value) { 846 tmpval = BUF_strdup(value); 847 if(!tmpval) return 0; 848 } else tmpval = NULL; 849 /* Parameter values are case sensitive so leave as is */ 850 mparam = (MIME_PARAM *) OPENSSL_malloc(sizeof(MIME_PARAM)); 851 if(!mparam) return 0; 852 mparam->param_name = tmpname; 853 mparam->param_value = tmpval; 854 sk_MIME_PARAM_push(mhdr->params, mparam); 855 return 1; 856 } 857 858 static int mime_hdr_cmp(const MIME_HEADER * const *a, 859 const MIME_HEADER * const *b) 860 { 861 return(strcmp((*a)->name, (*b)->name)); 862 } 863 864 static int mime_param_cmp(const MIME_PARAM * const *a, 865 const MIME_PARAM * const *b) 866 { 867 return(strcmp((*a)->param_name, (*b)->param_name)); 868 } 869 870 /* Find a header with a given name (if possible) */ 871 872 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name) 873 { 874 MIME_HEADER htmp; 875 int idx; 876 htmp.name = name; 877 idx = sk_MIME_HEADER_find(hdrs, &htmp); 878 if(idx < 0) return NULL; 879 return sk_MIME_HEADER_value(hdrs, idx); 880 } 881 882 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name) 883 { 884 MIME_PARAM param; 885 int idx; 886 param.param_name = name; 887 idx = sk_MIME_PARAM_find(hdr->params, ¶m); 888 if(idx < 0) return NULL; 889 return sk_MIME_PARAM_value(hdr->params, idx); 890 } 891 892 static void mime_hdr_free(MIME_HEADER *hdr) 893 { 894 if(hdr->name) OPENSSL_free(hdr->name); 895 if(hdr->value) OPENSSL_free(hdr->value); 896 if(hdr->params) sk_MIME_PARAM_pop_free(hdr->params, mime_param_free); 897 OPENSSL_free(hdr); 898 } 899 900 static void mime_param_free(MIME_PARAM *param) 901 { 902 if(param->param_name) OPENSSL_free(param->param_name); 903 if(param->param_value) OPENSSL_free(param->param_value); 904 OPENSSL_free(param); 905 } 906 907 /* Check for a multipart boundary. Returns: 908 * 0 : no boundary 909 * 1 : part boundary 910 * 2 : final boundary 911 */ 912 static int mime_bound_check(char *line, int linelen, char *bound, int blen) 913 { 914 if(linelen == -1) linelen = strlen(line); 915 if(blen == -1) blen = strlen(bound); 916 /* Quickly eliminate if line length too short */ 917 if(blen + 2 > linelen) return 0; 918 /* Check for part boundary */ 919 if(!strncmp(line, "--", 2) && !strncmp(line + 2, bound, blen)) { 920 if(!strncmp(line + blen + 2, "--", 2)) return 2; 921 else return 1; 922 } 923 return 0; 924 } 925 926 static int strip_eol(char *linebuf, int *plen) 927 { 928 int len = *plen; 929 char *p, c; 930 int is_eol = 0; 931 p = linebuf + len - 1; 932 for (p = linebuf + len - 1; len > 0; len--, p--) 933 { 934 c = *p; 935 if (c == '\n') 936 is_eol = 1; 937 else if (c != '\r') 938 break; 939 } 940 *plen = len; 941 return is_eol; 942 } 943
