crypto/pkcs7/pk7_smime.c

   1 /* pk7_smime.c */
   2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
   3  * project.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 1999-2004 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@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  * This product includes cryptographic software written by Eric Young
  54  * (eay@cryptsoft.com).  This product includes software written by Tim
  55  * Hudson (tjh@cryptsoft.com).
  56  *
  57  */
  58
  59 /* Simple PKCS#7 processing functions */
  60
  61 #include <stdio.h>
  62 #include "cryptlib.h"
  63 #include <openssl/x509.h>
  64 #include <openssl/x509v3.h>
  65
  66 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si);
  67
  68 PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
  69                   BIO *data, int flags)
  70 {
  71         PKCS7 *p7;
  72         int i;
  73
  74         if(!(p7 = PKCS7_new()))
  75                 {
  76                 PKCS7err(PKCS7_F_PKCS7_SIGN,ERR_R_MALLOC_FAILURE);
  77                 return NULL;
  78                 }
  79
  80         if (!PKCS7_set_type(p7, NID_pkcs7_signed))
  81                 goto err;
  82
  83         if (!PKCS7_content_new(p7, NID_pkcs7_data))
  84                 goto err;
  85
  86         if (pkey && !PKCS7_sign_add_signer(p7, signcert, pkey, NULL, flags))
  87                 {
  88                 PKCS7err(PKCS7_F_PKCS7_SIGN,PKCS7_R_PKCS7_ADD_SIGNER_ERROR);
  89                 goto err;
  90                 }
  91
  92         if(!(flags & PKCS7_NOCERTS))
  93                 {
  94                 for(i = 0; i < sk_X509_num(certs); i++)
  95                         {
  96                         if (!PKCS7_add_certificate(p7, sk_X509_value(certs, i)))
  97                                 goto err;
  98                         }
  99                 }
 100
 101         if (flags & (PKCS7_STREAM|PKCS7_PARTIAL))
 102                 return p7;
 103
 104         if (PKCS7_final(p7, data, flags))
 105                 return p7;
 106
 107         err:
 108         PKCS7_free(p7);
 109         return NULL;
 110 }
 111
 112 int PKCS7_final(PKCS7 *p7, BIO *data, int flags)
 113         {
 114         BIO *p7bio;
 115         int ret = 0;
 116         if (!(p7bio = PKCS7_dataInit(p7, NULL)))
 117                 {
 118                 PKCS7err(PKCS7_F_PKCS7_FINAL,ERR_R_MALLOC_FAILURE);
 119                 return 0;
 120                 }
 121
 122         SMIME_crlf_copy(data, p7bio, flags);
 123
 124         if(PKCS7_type_is_signed(p7) && (flags & PKCS7_DETACHED))
 125                 PKCS7_set_detached(p7, 1);
 126
 127         if (!PKCS7_dataFinal(p7,p7bio))
 128                 {
 129                 PKCS7err(PKCS7_F_PKCS7_FINAL,PKCS7_R_PKCS7_DATASIGN);
 130                 goto err;
 131                 }
 132
 133         ret = 1;
 134
 135         err:
 136         BIO_free_all(p7bio);
 137
 138         return ret;
 139
 140         }
 141
 142 /* Check to see if a cipher exists and if so add S/MIME capabilities */
 143
 144 static int add_cipher_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
 145         {
 146         if (EVP_get_cipherbynid(nid))
 147                 return PKCS7_simple_smimecap(sk, nid, arg);
 148         return 1;
 149         }
 150
 151 PKCS7_SIGNER_INFO *PKCS7_sign_add_signer(PKCS7 *p7, X509 *signcert,
 152                                         EVP_PKEY *pkey, const EVP_MD *md,
 153                                         int flags)
 154         {
 155         PKCS7_SIGNER_INFO *si = NULL;
 156         int si_free = 1;
 157         STACK_OF(X509_ALGOR) *smcap = NULL;
 158         if(!X509_check_private_key(signcert, pkey))
 159                 {
 160                 PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
 161                         PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
 162                 return NULL;
 163                 }
 164
 165         if (!(si = PKCS7_add_signature(p7,signcert,pkey, md)))
 166                 {
 167                 PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
 168                                 PKCS7_R_PKCS7_ADD_SIGNATURE_ERROR);
 169                 return NULL;
 170                 }
 171
 172         /* si is now part of p7 so don't free it on error */
 173
 174         si_free = 0;
 175
 176         if(!(flags & PKCS7_NOCERTS))
 177                 {
 178                 if (!PKCS7_add_certificate(p7, signcert))
 179                         goto err;
 180                 }
 181
 182         if(!(flags & PKCS7_NOATTR))
 183                 {
 184                 if (!PKCS7_add_attrib_content_type(si, NULL))
 185                         goto err;
 186                 /* Add SMIMECapabilities */
 187                 if(!(flags & PKCS7_NOSMIMECAP))
 188                         {
 189                         if(!(smcap = sk_X509_ALGOR_new_null()))
 190                                 {
 191                                 PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
 192                                         ERR_R_MALLOC_FAILURE);
 193                                 goto err;
 194                                 }
 195                         if (!add_cipher_smcap(smcap, NID_des_ede3_cbc, -1)
 196                                 || !add_cipher_smcap(smcap, NID_rc2_cbc, 128)
 197                                 || !add_cipher_smcap(smcap, NID_rc2_cbc, 64)
 198                                 || !add_cipher_smcap(smcap, NID_des_cbc, -1)
 199                                 || !add_cipher_smcap(smcap, NID_rc2_cbc, 40)
 200                                 || !PKCS7_add_attrib_smimecap (si, smcap))
 201                                 goto err;
 202                         sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
 203                         smcap = NULL;
 204                         }
 205                 if (flags & PKCS7_REUSE_DIGEST)
 206                         {
 207                         if (!pkcs7_copy_existing_digest(p7, si))
 208                                 goto err;
 209                         if (!PKCS7_SIGNER_INFO_sign(si))
 210                                 goto err;
 211                         }
 212                 }
 213         return si;
 214         err:
 215         if (smcap)
 216                 sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
 217         if (si && si_free)
 218                 PKCS7_SIGNER_INFO_free(si);
 219         return NULL;
 220         }
 221
 222 /* Search for a digest matching SignerInfo digest type and if found
 223  * copy across.
 224  */
 225
 226 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
 227         {
 228         int i;
 229         STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
 230         PKCS7_SIGNER_INFO *sitmp;
 231         ASN1_OCTET_STRING *osdig = NULL;
 232         sinfos = PKCS7_get_signer_info(p7);
 233         for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++)
 234                 {
 235                 sitmp = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
 236                 if (si == sitmp)
 237                         break;
 238                 if (sk_X509_ATTRIBUTE_num(sitmp->auth_attr) <= 0)
 239                         continue;
 240                 if (!OBJ_cmp(si->digest_alg->algorithm,
 241                                 sitmp->digest_alg->algorithm))
 242                         {
 243                         osdig = PKCS7_digest_from_attributes(sitmp->auth_attr);
 244                         break;
 245                         }
 246
 247                 }
 248
 249         if (osdig)
 250                 return PKCS7_add1_attrib_digest(si, osdig->data, osdig->length);
 251
 252         PKCS7err(PKCS7_F_PKCS7_COPY_EXISTING_DIGEST,
 253                         PKCS7_R_NO_MATCHING_DIGEST_TYPE_FOUND);
 254         return 0;
 255         }
 256
 257 int PKCS7_verify(PKCS7 *p7, STACK_OF(X509) *certs, X509_STORE *store,
 258                                         BIO *indata, BIO *out, int flags)
 259 {
 260         STACK_OF(X509) *signers;
 261         X509 *signer;
 262         STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
 263         PKCS7_SIGNER_INFO *si;
 264         X509_STORE_CTX cert_ctx;
 265         char buf[4096];
 266         int i, j=0, k, ret = 0;
 267         BIO *p7bio;
 268         BIO *tmpin, *tmpout;
 269
 270         if(!p7) {
 271                 PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_INVALID_NULL_POINTER);
 272                 return 0;
 273         }
 274
 275         if(!PKCS7_type_is_signed(p7)) {
 276                 PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_WRONG_CONTENT_TYPE);
 277                 return 0;
 278         }
 279
 280         /* Check for no data and no content: no data to verify signature */
 281         if(PKCS7_get_detached(p7) && !indata) {
 282                 PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_NO_CONTENT);
 283                 return 0;
 284         }
 285 #if 0
 286         /* NB: this test commented out because some versions of Netscape
 287          * illegally include zero length content when signing data.
 288          */
 289
 290         /* Check for data and content: two sets of data */
 291         if(!PKCS7_get_detached(p7) && indata) {
 292                                 PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_CONTENT_AND_DATA_PRESENT);
 293                 return 0;
 294         }
 295 #endif
 296
 297         sinfos = PKCS7_get_signer_info(p7);
 298
 299         if(!sinfos || !sk_PKCS7_SIGNER_INFO_num(sinfos)) {
 300                 PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_NO_SIGNATURES_ON_DATA);
 301                 return 0;
 302         }
 303
 304
 305         signers = PKCS7_get0_signers(p7, certs, flags);
 306
 307         if(!signers) return 0;
 308
 309         /* Now verify the certificates */
 310
 311         if (!(flags & PKCS7_NOVERIFY)) for (k = 0; k < sk_X509_num(signers); k++) {
 312                 signer = sk_X509_value (signers, k);
 313                 if (!(flags & PKCS7_NOCHAIN)) {
 314                         if(!X509_STORE_CTX_init(&cert_ctx, store, signer,
 315                                                         p7->d.sign->cert))
 316                                 {
 317                                 PKCS7err(PKCS7_F_PKCS7_VERIFY,ERR_R_X509_LIB);
 318                                 sk_X509_free(signers);
 319                                 return 0;
 320                                 }
 321                         X509_STORE_CTX_set_purpose(&cert_ctx,
 322                                                 X509_PURPOSE_SMIME_SIGN);
 323                 } else if(!X509_STORE_CTX_init (&cert_ctx, store, signer, NULL)) {
 324                         PKCS7err(PKCS7_F_PKCS7_VERIFY,ERR_R_X509_LIB);
 325                         sk_X509_free(signers);
 326                         return 0;
 327                 }
 328                 if (!(flags & PKCS7_NOCRL))
 329                         X509_STORE_CTX_set0_crls(&cert_ctx, p7->d.sign->crl);
 330                 i = X509_verify_cert(&cert_ctx);
 331                 if (i <= 0) j = X509_STORE_CTX_get_error(&cert_ctx);
 332                 X509_STORE_CTX_cleanup(&cert_ctx);
 333                 if (i <= 0) {
 334                         PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_CERTIFICATE_VERIFY_ERROR);
 335                         ERR_add_error_data(2, "Verify error:",
 336                                          X509_verify_cert_error_string(j));
 337                         sk_X509_free(signers);
 338                         return 0;
 339                 }
 340                 /* Check for revocation status here */
 341         }
 342
 343         /* Performance optimization: if the content is a memory BIO then
 344          * store its contents in a temporary read only memory BIO. This
 345          * avoids potentially large numbers of slow copies of data which will
 346          * occur when reading from a read write memory BIO when signatures
 347          * are calculated.
 348          */
 349
 350         if (indata && (BIO_method_type(indata) == BIO_TYPE_MEM))
 351                 {
 352                 char *ptr;
 353                 long len;
 354                 len = BIO_get_mem_data(indata, &ptr);
 355                 tmpin = BIO_new_mem_buf(ptr, len);
 356                 if (tmpin == NULL)
 357                         {
 358                         PKCS7err(PKCS7_F_PKCS7_VERIFY,ERR_R_MALLOC_FAILURE);
 359                         return 0;
 360                         }
 361                 }
 362         else
 363                 tmpin = indata;
 364
 365
 366         p7bio=PKCS7_dataInit(p7,tmpin);
 367
 368         if(flags & PKCS7_TEXT) {
 369                 if(!(tmpout = BIO_new(BIO_s_mem()))) {
 370                         PKCS7err(PKCS7_F_PKCS7_VERIFY,ERR_R_MALLOC_FAILURE);
 371                         goto err;
 372                 }
 373         } else tmpout = out;
 374
 375         /* We now have to 'read' from p7bio to calculate digests etc. */
 376         for (;;)
 377         {
 378                 i=BIO_read(p7bio,buf,sizeof(buf));
 379                 if (i <= 0) break;
 380                 if (tmpout) BIO_write(tmpout, buf, i);
 381         }
 382
 383         if(flags & PKCS7_TEXT) {
 384                 if(!SMIME_text(tmpout, out)) {
 385                         PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_SMIME_TEXT_ERROR);
 386                         BIO_free(tmpout);
 387                         goto err;
 388                 }
 389                 BIO_free(tmpout);
 390         }
 391
 392         /* Now Verify All Signatures */
 393         if (!(flags & PKCS7_NOSIGS))
 394             for (i=0; i<sk_PKCS7_SIGNER_INFO_num(sinfos); i++)
 395                 {
 396                 si=sk_PKCS7_SIGNER_INFO_value(sinfos,i);
 397                 signer = sk_X509_value (signers, i);
 398                 j=PKCS7_signatureVerify(p7bio,p7,si, signer);
 399                 if (j <= 0) {
 400                         PKCS7err(PKCS7_F_PKCS7_VERIFY,PKCS7_R_SIGNATURE_FAILURE);
 401                         goto err;
 402                 }
 403         }
 404
 405         ret = 1;
 406
 407         err:
 408
 409         if (tmpin == indata)
 410                 {
 411                 if (indata) BIO_pop(p7bio);
 412                 }
 413         BIO_free_all(p7bio);
 414
 415         sk_X509_free(signers);
 416
 417         return ret;
 418 }
 419
 420 STACK_OF(X509) *PKCS7_get0_signers(PKCS7 *p7, STACK_OF(X509) *certs, int flags)
 421 {
 422         STACK_OF(X509) *signers;
 423         STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
 424         PKCS7_SIGNER_INFO *si;
 425         PKCS7_ISSUER_AND_SERIAL *ias;
 426         X509 *signer;
 427         int i;
 428
 429         if(!p7) {
 430                 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,PKCS7_R_INVALID_NULL_POINTER);
 431                 return NULL;
 432         }
 433
 434         if(!PKCS7_type_is_signed(p7)) {
 435                 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,PKCS7_R_WRONG_CONTENT_TYPE);
 436                 return NULL;
 437         }
 438
 439         /* Collect all the signers together */
 440
 441         sinfos = PKCS7_get_signer_info(p7);
 442
 443         if(sk_PKCS7_SIGNER_INFO_num(sinfos) <= 0) {
 444                 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,PKCS7_R_NO_SIGNERS);
 445                 return 0;
 446         }
 447
 448         if(!(signers = sk_X509_new_null())) {
 449                 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,ERR_R_MALLOC_FAILURE);
 450                 return NULL;
 451         }
 452
 453         for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++)
 454         {
 455             si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
 456             ias = si->issuer_and_serial;
 457             signer = NULL;
 458                 /* If any certificates passed they take priority */
 459             if (certs) signer = X509_find_by_issuer_and_serial (certs,
 460                                                 ias->issuer, ias->serial);
 461             if (!signer && !(flags & PKCS7_NOINTERN)
 462                         && p7->d.sign->cert) signer =
 463                               X509_find_by_issuer_and_serial (p7->d.sign->cert,
 464                                                 ias->issuer, ias->serial);
 465             if (!signer) {
 466                         PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,PKCS7_R_SIGNER_CERTIFICATE_NOT_FOUND);
 467                         sk_X509_free(signers);
 468                         return 0;
 469             }
 470
 471             sk_X509_push(signers, signer);
 472         }
 473         return signers;
 474 }
 475
 476
 477 /* Build a complete PKCS#7 enveloped data */
 478
 479 PKCS7 *PKCS7_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher,
 480                                                                 int flags)
 481 {
 482         PKCS7 *p7;
 483         BIO *p7bio = NULL;
 484         int i;
 485         X509 *x509;
 486         if(!(p7 = PKCS7_new())) {
 487                 PKCS7err(PKCS7_F_PKCS7_ENCRYPT,ERR_R_MALLOC_FAILURE);
 488                 return NULL;
 489         }
 490
 491         PKCS7_set_type(p7, NID_pkcs7_enveloped);
 492         if(!PKCS7_set_cipher(p7, cipher)) {
 493                 PKCS7err(PKCS7_F_PKCS7_ENCRYPT,PKCS7_R_ERROR_SETTING_CIPHER);
 494                 goto err;
 495         }
 496
 497         for(i = 0; i < sk_X509_num(certs); i++) {
 498                 x509 = sk_X509_value(certs, i);
 499                 if(!PKCS7_add_recipient(p7, x509)) {
 500                         PKCS7err(PKCS7_F_PKCS7_ENCRYPT,
 501                                         PKCS7_R_ERROR_ADDING_RECIPIENT);
 502                         goto err;
 503                 }
 504         }
 505
 506         if (PKCS7_final(p7, in, flags))
 507                 return p7;
 508
 509         err:
 510
 511         BIO_free(p7bio);
 512         PKCS7_free(p7);
 513         return NULL;
 514
 515 }
 516
 517 int PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
 518 {
 519         BIO *tmpmem;
 520         int ret, i;
 521         char buf[4096];
 522
 523         if(!p7) {
 524                 PKCS7err(PKCS7_F_PKCS7_DECRYPT,PKCS7_R_INVALID_NULL_POINTER);
 525                 return 0;
 526         }
 527
 528         if(!PKCS7_type_is_enveloped(p7)) {
 529                 PKCS7err(PKCS7_F_PKCS7_DECRYPT,PKCS7_R_WRONG_CONTENT_TYPE);
 530                 return 0;
 531         }
 532
 533         if(cert && !X509_check_private_key(cert, pkey)) {
 534                 PKCS7err(PKCS7_F_PKCS7_DECRYPT,
 535                                 PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
 536                 return 0;
 537         }
 538
 539         if(!(tmpmem = PKCS7_dataDecode(p7, pkey, NULL, cert))) {
 540                 PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_DECRYPT_ERROR);
 541                 return 0;
 542         }
 543
 544         if (flags & PKCS7_TEXT) {
 545                 BIO *tmpbuf, *bread;
 546                 /* Encrypt BIOs can't do BIO_gets() so add a buffer BIO */
 547                 if(!(tmpbuf = BIO_new(BIO_f_buffer()))) {
 548                         PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
 549                         return 0;
 550                 }
 551                 if(!(bread = BIO_push(tmpbuf, tmpmem))) {
 552                         PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
 553                         return 0;
 554                 }
 555                 ret = SMIME_text(bread, data);
 556                 BIO_free_all(bread);
 557                 return ret;
 558         } else {
 559                 for(;;) {
 560                         i = BIO_read(tmpmem, buf, sizeof(buf));
 561                         if(i <= 0) break;
 562                         BIO_write(data, buf, i);
 563                 }
 564                 BIO_free_all(tmpmem);
 565                 return 1;
 566         }
 567 }