crypto/pkcs7/pk7_doit.c

   1 /* crypto/pkcs7/pk7_doit.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58
  59 #include <stdio.h>
  60 #include "cryptlib.h"
  61 #include <openssl/rand.h>
  62 #include <openssl/objects.h>
  63 #include <openssl/x509.h>
  64 #include <openssl/x509v3.h>
  65 #include <openssl/err.h>
  66
  67 static int add_attribute(STACK_OF(X509_ATTRIBUTE) **sk, int nid, int atrtype,
  68                          void *value);
  69 static ASN1_TYPE *get_attribute(STACK_OF(X509_ATTRIBUTE) *sk, int nid);
  70
  71 static int PKCS7_type_is_other(PKCS7 *p7)
  72 {
  73     int isOther = 1;
  74
  75     int nid = OBJ_obj2nid(p7->type);
  76
  77     switch (nid) {
  78     case NID_pkcs7_data:
  79     case NID_pkcs7_signed:
  80     case NID_pkcs7_enveloped:
  81     case NID_pkcs7_signedAndEnveloped:
  82     case NID_pkcs7_digest:
  83     case NID_pkcs7_encrypted:
  84         isOther = 0;
  85         break;
  86     default:
  87         isOther = 1;
  88     }
  89
  90     return isOther;
  91
  92 }
  93
  94 static ASN1_OCTET_STRING *PKCS7_get_octet_string(PKCS7 *p7)
  95 {
  96     if (PKCS7_type_is_data(p7))
  97         return p7->d.data;
  98     if (PKCS7_type_is_other(p7) && p7->d.other
  99         && (p7->d.other->type == V_ASN1_OCTET_STRING))
 100         return p7->d.other->value.octet_string;
 101     return NULL;
 102 }
 103
 104 static int PKCS7_bio_add_digest(BIO **pbio, X509_ALGOR *alg)
 105 {
 106     BIO *btmp;
 107     const EVP_MD *md;
 108     if ((btmp = BIO_new(BIO_f_md())) == NULL) {
 109         PKCS7err(PKCS7_F_PKCS7_BIO_ADD_DIGEST, ERR_R_BIO_LIB);
 110         goto err;
 111     }
 112
 113     md = EVP_get_digestbyobj(alg->algorithm);
 114     if (md == NULL) {
 115         PKCS7err(PKCS7_F_PKCS7_BIO_ADD_DIGEST, PKCS7_R_UNKNOWN_DIGEST_TYPE);
 116         goto err;
 117     }
 118
 119     BIO_set_md(btmp, md);
 120     if (*pbio == NULL)
 121         *pbio = btmp;
 122     else if (!BIO_push(*pbio, btmp)) {
 123         PKCS7err(PKCS7_F_PKCS7_BIO_ADD_DIGEST, ERR_R_BIO_LIB);
 124         goto err;
 125     }
 126     btmp = NULL;
 127
 128     return 1;
 129
 130  err:
 131     BIO_free(btmp);
 132     return 0;
 133
 134 }
 135
 136 static int pkcs7_encode_rinfo(PKCS7_RECIP_INFO *ri,
 137                               unsigned char *key, int keylen)
 138 {
 139     EVP_PKEY_CTX *pctx = NULL;
 140     EVP_PKEY *pkey = NULL;
 141     unsigned char *ek = NULL;
 142     int ret = 0;
 143     size_t eklen;
 144
 145     pkey = X509_get_pubkey(ri->cert);
 146
 147     if (!pkey)
 148         return 0;
 149
 150     pctx = EVP_PKEY_CTX_new(pkey, NULL);
 151     if (!pctx)
 152         return 0;
 153
 154     if (EVP_PKEY_encrypt_init(pctx) <= 0)
 155         goto err;
 156
 157     if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_ENCRYPT,
 158                           EVP_PKEY_CTRL_PKCS7_ENCRYPT, 0, ri) <= 0) {
 159         PKCS7err(PKCS7_F_PKCS7_ENCODE_RINFO, PKCS7_R_CTRL_ERROR);
 160         goto err;
 161     }
 162
 163     if (EVP_PKEY_encrypt(pctx, NULL, &eklen, key, keylen) <= 0)
 164         goto err;
 165
 166     ek = OPENSSL_malloc(eklen);
 167
 168     if (ek == NULL) {
 169         PKCS7err(PKCS7_F_PKCS7_ENCODE_RINFO, ERR_R_MALLOC_FAILURE);
 170         goto err;
 171     }
 172
 173     if (EVP_PKEY_encrypt(pctx, ek, &eklen, key, keylen) <= 0)
 174         goto err;
 175
 176     ASN1_STRING_set0(ri->enc_key, ek, eklen);
 177     ek = NULL;
 178
 179     ret = 1;
 180
 181  err:
 182     EVP_PKEY_free(pkey);
 183     EVP_PKEY_CTX_free(pctx);
 184     OPENSSL_free(ek);
 185     return ret;
 186
 187 }
 188
 189 static int pkcs7_decrypt_rinfo(unsigned char **pek, int *peklen,
 190                                PKCS7_RECIP_INFO *ri, EVP_PKEY *pkey)
 191 {
 192     EVP_PKEY_CTX *pctx = NULL;
 193     unsigned char *ek = NULL;
 194     size_t eklen;
 195
 196     int ret = -1;
 197
 198     pctx = EVP_PKEY_CTX_new(pkey, NULL);
 199     if (!pctx)
 200         return -1;
 201
 202     if (EVP_PKEY_decrypt_init(pctx) <= 0)
 203         goto err;
 204
 205     if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_DECRYPT,
 206                           EVP_PKEY_CTRL_PKCS7_DECRYPT, 0, ri) <= 0) {
 207         PKCS7err(PKCS7_F_PKCS7_DECRYPT_RINFO, PKCS7_R_CTRL_ERROR);
 208         goto err;
 209     }
 210
 211     if (EVP_PKEY_decrypt(pctx, NULL, &eklen,
 212                          ri->enc_key->data, ri->enc_key->length) <= 0)
 213         goto err;
 214
 215     ek = OPENSSL_malloc(eklen);
 216
 217     if (ek == NULL) {
 218         PKCS7err(PKCS7_F_PKCS7_DECRYPT_RINFO, ERR_R_MALLOC_FAILURE);
 219         goto err;
 220     }
 221
 222     if (EVP_PKEY_decrypt(pctx, ek, &eklen,
 223                          ri->enc_key->data, ri->enc_key->length) <= 0) {
 224         ret = 0;
 225         PKCS7err(PKCS7_F_PKCS7_DECRYPT_RINFO, ERR_R_EVP_LIB);
 226         goto err;
 227     }
 228
 229     ret = 1;
 230
 231     OPENSSL_clear_free(*pek, *peklen);
 232     *pek = ek;
 233     *peklen = eklen;
 234
 235  err:
 236     EVP_PKEY_CTX_free(pctx);
 237     if (!ret)
 238         OPENSSL_free(ek);
 239
 240     return ret;
 241 }
 242
 243 BIO *PKCS7_dataInit(PKCS7 *p7, BIO *bio)
 244 {
 245     int i;
 246     BIO *out = NULL, *btmp = NULL;
 247     X509_ALGOR *xa = NULL;
 248     const EVP_CIPHER *evp_cipher = NULL;
 249     STACK_OF(X509_ALGOR) *md_sk = NULL;
 250     STACK_OF(PKCS7_RECIP_INFO) *rsk = NULL;
 251     X509_ALGOR *xalg = NULL;
 252     PKCS7_RECIP_INFO *ri = NULL;
 253     ASN1_OCTET_STRING *os = NULL;
 254
 255     if (p7 == NULL) {
 256         PKCS7err(PKCS7_F_PKCS7_DATAINIT, PKCS7_R_INVALID_NULL_POINTER);
 257         return NULL;
 258     }
 259     /*
 260      * The content field in the PKCS7 ContentInfo is optional, but that really
 261      * only applies to inner content (precisely, detached signatures).
 262      *
 263      * When reading content, missing outer content is therefore treated as an
 264      * error.
 265      *
 266      * When creating content, PKCS7_content_new() must be called before
 267      * calling this method, so a NULL p7->d is always an error.
 268      */
 269     if (p7->d.ptr == NULL) {
 270         PKCS7err(PKCS7_F_PKCS7_DATAINIT, PKCS7_R_NO_CONTENT);
 271         return NULL;
 272     }
 273
 274     i = OBJ_obj2nid(p7->type);
 275     p7->state = PKCS7_S_HEADER;
 276
 277     switch (i) {
 278     case NID_pkcs7_signed:
 279         md_sk = p7->d.sign->md_algs;
 280         os = PKCS7_get_octet_string(p7->d.sign->contents);
 281         break;
 282     case NID_pkcs7_signedAndEnveloped:
 283         rsk = p7->d.signed_and_enveloped->recipientinfo;
 284         md_sk = p7->d.signed_and_enveloped->md_algs;
 285         xalg = p7->d.signed_and_enveloped->enc_data->algorithm;
 286         evp_cipher = p7->d.signed_and_enveloped->enc_data->cipher;
 287         if (evp_cipher == NULL) {
 288             PKCS7err(PKCS7_F_PKCS7_DATAINIT, PKCS7_R_CIPHER_NOT_INITIALIZED);
 289             goto err;
 290         }
 291         break;
 292     case NID_pkcs7_enveloped:
 293         rsk = p7->d.enveloped->recipientinfo;
 294         xalg = p7->d.enveloped->enc_data->algorithm;
 295         evp_cipher = p7->d.enveloped->enc_data->cipher;
 296         if (evp_cipher == NULL) {
 297             PKCS7err(PKCS7_F_PKCS7_DATAINIT, PKCS7_R_CIPHER_NOT_INITIALIZED);
 298             goto err;
 299         }
 300         break;
 301     case NID_pkcs7_digest:
 302         xa = p7->d.digest->md;
 303         os = PKCS7_get_octet_string(p7->d.digest->contents);
 304         break;
 305     case NID_pkcs7_data:
 306         break;
 307     default:
 308         PKCS7err(PKCS7_F_PKCS7_DATAINIT, PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
 309         goto err;
 310     }
 311
 312     for (i = 0; i < sk_X509_ALGOR_num(md_sk); i++)
 313         if (!PKCS7_bio_add_digest(&out, sk_X509_ALGOR_value(md_sk, i)))
 314             goto err;
 315
 316     if (xa && !PKCS7_bio_add_digest(&out, xa))
 317         goto err;
 318
 319     if (evp_cipher != NULL) {
 320         unsigned char key[EVP_MAX_KEY_LENGTH];
 321         unsigned char iv[EVP_MAX_IV_LENGTH];
 322         int keylen, ivlen;
 323         EVP_CIPHER_CTX *ctx;
 324
 325         if ((btmp = BIO_new(BIO_f_cipher())) == NULL) {
 326             PKCS7err(PKCS7_F_PKCS7_DATAINIT, ERR_R_BIO_LIB);
 327             goto err;
 328         }
 329         BIO_get_cipher_ctx(btmp, &ctx);
 330         keylen = EVP_CIPHER_key_length(evp_cipher);
 331         ivlen = EVP_CIPHER_iv_length(evp_cipher);
 332         xalg->algorithm = OBJ_nid2obj(EVP_CIPHER_type(evp_cipher));
 333         if (ivlen > 0)
 334             if (RAND_bytes(iv, ivlen) <= 0)
 335                 goto err;
 336         if (EVP_CipherInit_ex(ctx, evp_cipher, NULL, NULL, NULL, 1) <= 0)
 337             goto err;
 338         if (EVP_CIPHER_CTX_rand_key(ctx, key) <= 0)
 339             goto err;
 340         if (EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, 1) <= 0)
 341             goto err;
 342
 343         if (ivlen > 0) {
 344             if (xalg->parameter == NULL) {
 345                 xalg->parameter = ASN1_TYPE_new();
 346                 if (xalg->parameter == NULL)
 347                     goto err;
 348             }
 349             if (EVP_CIPHER_param_to_asn1(ctx, xalg->parameter) < 0)
 350                 goto err;
 351         }
 352
 353         /* Lets do the pub key stuff :-) */
 354         for (i = 0; i < sk_PKCS7_RECIP_INFO_num(rsk); i++) {
 355             ri = sk_PKCS7_RECIP_INFO_value(rsk, i);
 356             if (pkcs7_encode_rinfo(ri, key, keylen) <= 0)
 357                 goto err;
 358         }
 359         OPENSSL_cleanse(key, keylen);
 360
 361         if (out == NULL)
 362             out = btmp;
 363         else
 364             BIO_push(out, btmp);
 365         btmp = NULL;
 366     }
 367
 368     if (bio == NULL) {
 369         if (PKCS7_is_detached(p7))
 370             bio = BIO_new(BIO_s_null());
 371         else if (os && os->length > 0)
 372             bio = BIO_new_mem_buf(os->data, os->length);
 373         if (bio == NULL) {
 374             bio = BIO_new(BIO_s_mem());
 375             if (bio == NULL)
 376                 goto err;
 377             BIO_set_mem_eof_return(bio, 0);
 378         }
 379     }
 380     if (out)
 381         BIO_push(out, bio);
 382     else
 383         out = bio;
 384     return out;
 385
 386  err:
 387     BIO_free_all(out);
 388     BIO_free_all(btmp);
 389     return NULL;
 390 }
 391
 392 static int pkcs7_cmp_ri(PKCS7_RECIP_INFO *ri, X509 *pcert)
 393 {
 394     int ret;
 395     ret = X509_NAME_cmp(ri->issuer_and_serial->issuer,
 396                         pcert->cert_info->issuer);
 397     if (ret)
 398         return ret;
 399     return ASN1_INTEGER_cmp(pcert->cert_info->serialNumber,
 400                               ri->issuer_and_serial->serial);
 401 }
 402
 403 /* int */
 404 BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert)
 405 {
 406     int i, j;
 407     BIO *out = NULL, *btmp = NULL, *etmp = NULL, *bio = NULL;
 408     X509_ALGOR *xa;
 409     ASN1_OCTET_STRING *data_body = NULL;
 410     const EVP_MD *evp_md;
 411     const EVP_CIPHER *evp_cipher = NULL;
 412     EVP_CIPHER_CTX *evp_ctx = NULL;
 413     X509_ALGOR *enc_alg = NULL;
 414     STACK_OF(X509_ALGOR) *md_sk = NULL;
 415     STACK_OF(PKCS7_RECIP_INFO) *rsk = NULL;
 416     PKCS7_RECIP_INFO *ri = NULL;
 417     unsigned char *ek = NULL, *tkey = NULL;
 418     int eklen = 0, tkeylen = 0;
 419
 420     if (p7 == NULL) {
 421         PKCS7err(PKCS7_F_PKCS7_DATADECODE, PKCS7_R_INVALID_NULL_POINTER);
 422         return NULL;
 423     }
 424
 425     if (p7->d.ptr == NULL) {
 426         PKCS7err(PKCS7_F_PKCS7_DATADECODE, PKCS7_R_NO_CONTENT);
 427         return NULL;
 428     }
 429
 430     i = OBJ_obj2nid(p7->type);
 431     p7->state = PKCS7_S_HEADER;
 432
 433     switch (i) {
 434     case NID_pkcs7_signed:
 435         data_body = PKCS7_get_octet_string(p7->d.sign->contents);
 436         if (!PKCS7_is_detached(p7) && data_body == NULL) {
 437             PKCS7err(PKCS7_F_PKCS7_DATADECODE,
 438                      PKCS7_R_INVALID_SIGNED_DATA_TYPE);
 439             goto err;
 440         }
 441         md_sk = p7->d.sign->md_algs;
 442         break;
 443     case NID_pkcs7_signedAndEnveloped:
 444         rsk = p7->d.signed_and_enveloped->recipientinfo;
 445         md_sk = p7->d.signed_and_enveloped->md_algs;
 446         data_body = p7->d.signed_and_enveloped->enc_data->enc_data;
 447         enc_alg = p7->d.signed_and_enveloped->enc_data->algorithm;
 448         evp_cipher = EVP_get_cipherbyobj(enc_alg->algorithm);
 449         if (evp_cipher == NULL) {
 450             PKCS7err(PKCS7_F_PKCS7_DATADECODE,
 451                      PKCS7_R_UNSUPPORTED_CIPHER_TYPE);
 452             goto err;
 453         }
 454         break;
 455     case NID_pkcs7_enveloped:
 456         rsk = p7->d.enveloped->recipientinfo;
 457         enc_alg = p7->d.enveloped->enc_data->algorithm;
 458         data_body = p7->d.enveloped->enc_data->enc_data;
 459         evp_cipher = EVP_get_cipherbyobj(enc_alg->algorithm);
 460         if (evp_cipher == NULL) {
 461             PKCS7err(PKCS7_F_PKCS7_DATADECODE,
 462                      PKCS7_R_UNSUPPORTED_CIPHER_TYPE);
 463             goto err;
 464         }
 465         break;
 466     default:
 467         PKCS7err(PKCS7_F_PKCS7_DATADECODE, PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
 468         goto err;
 469     }
 470
 471     /* We will be checking the signature */
 472     if (md_sk != NULL) {
 473         for (i = 0; i < sk_X509_ALGOR_num(md_sk); i++) {
 474             xa = sk_X509_ALGOR_value(md_sk, i);
 475             if ((btmp = BIO_new(BIO_f_md())) == NULL) {
 476                 PKCS7err(PKCS7_F_PKCS7_DATADECODE, ERR_R_BIO_LIB);
 477                 goto err;
 478             }
 479
 480             j = OBJ_obj2nid(xa->algorithm);
 481             evp_md = EVP_get_digestbynid(j);
 482             if (evp_md == NULL) {
 483                 PKCS7err(PKCS7_F_PKCS7_DATADECODE,
 484                          PKCS7_R_UNKNOWN_DIGEST_TYPE);
 485                 goto err;
 486             }
 487
 488             BIO_set_md(btmp, evp_md);
 489             if (out == NULL)
 490                 out = btmp;
 491             else
 492                 BIO_push(out, btmp);
 493             btmp = NULL;
 494         }
 495     }
 496
 497     if (evp_cipher != NULL) {
 498         if ((etmp = BIO_new(BIO_f_cipher())) == NULL) {
 499             PKCS7err(PKCS7_F_PKCS7_DATADECODE, ERR_R_BIO_LIB);
 500             goto err;
 501         }
 502
 503         /*
 504          * It was encrypted, we need to decrypt the secret key with the
 505          * private key
 506          */
 507
 508         /*
 509          * Find the recipientInfo which matches the passed certificate (if
 510          * any)
 511          */
 512
 513         if (pcert) {
 514             for (i = 0; i < sk_PKCS7_RECIP_INFO_num(rsk); i++) {
 515                 ri = sk_PKCS7_RECIP_INFO_value(rsk, i);
 516                 if (!pkcs7_cmp_ri(ri, pcert))
 517                     break;
 518                 ri = NULL;
 519             }
 520             if (ri == NULL) {
 521                 PKCS7err(PKCS7_F_PKCS7_DATADECODE,
 522                          PKCS7_R_NO_RECIPIENT_MATCHES_CERTIFICATE);
 523                 goto err;
 524             }
 525         }
 526
 527         /* If we haven't got a certificate try each ri in turn */
 528         if (pcert == NULL) {
 529             /*
 530              * Always attempt to decrypt all rinfo even after success as a
 531              * defence against MMA timing attacks.
 532              */
 533             for (i = 0; i < sk_PKCS7_RECIP_INFO_num(rsk); i++) {
 534                 ri = sk_PKCS7_RECIP_INFO_value(rsk, i);
 535
 536                 if (pkcs7_decrypt_rinfo(&ek, &eklen, ri, pkey) < 0)
 537                     goto err;
 538                 ERR_clear_error();
 539             }
 540         } else {
 541             /* Only exit on fatal errors, not decrypt failure */
 542             if (pkcs7_decrypt_rinfo(&ek, &eklen, ri, pkey) < 0)
 543                 goto err;
 544             ERR_clear_error();
 545         }
 546
 547         evp_ctx = NULL;
 548         BIO_get_cipher_ctx(etmp, &evp_ctx);
 549         if (EVP_CipherInit_ex(evp_ctx, evp_cipher, NULL, NULL, NULL, 0) <= 0)
 550             goto err;
 551         if (EVP_CIPHER_asn1_to_param(evp_ctx, enc_alg->parameter) < 0)
 552             goto err;
 553         /* Generate random key as MMA defence */
 554         tkeylen = EVP_CIPHER_CTX_key_length(evp_ctx);
 555         tkey = OPENSSL_malloc(tkeylen);
 556         if (!tkey)
 557             goto err;
 558         if (EVP_CIPHER_CTX_rand_key(evp_ctx, tkey) <= 0)
 559             goto err;
 560         if (ek == NULL) {
 561             ek = tkey;
 562             eklen = tkeylen;
 563             tkey = NULL;
 564         }
 565
 566         if (eklen != EVP_CIPHER_CTX_key_length(evp_ctx)) {
 567             /*
 568              * Some S/MIME clients don't use the same key and effective key
 569              * length. The key length is determined by the size of the
 570              * decrypted RSA key.
 571              */
 572             if (!EVP_CIPHER_CTX_set_key_length(evp_ctx, eklen)) {
 573                 /* Use random key as MMA defence */
 574                 OPENSSL_clear_free(ek, eklen);
 575                 ek = tkey;
 576                 eklen = tkeylen;
 577                 tkey = NULL;
 578             }
 579         }
 580         /* Clear errors so we don't leak information useful in MMA */
 581         ERR_clear_error();
 582         if (EVP_CipherInit_ex(evp_ctx, NULL, NULL, ek, NULL, 0) <= 0)
 583             goto err;
 584
 585         OPENSSL_clear_free(ek, eklen);
 586         ek = NULL;
 587         OPENSSL_clear_free(tkey, tkeylen);
 588         tkey = NULL;
 589
 590         if (out == NULL)
 591             out = etmp;
 592         else
 593             BIO_push(out, etmp);
 594         etmp = NULL;
 595     }
 596     if (PKCS7_is_detached(p7) || (in_bio != NULL)) {
 597         bio = in_bio;
 598     } else {
 599         if (data_body->length > 0)
 600             bio = BIO_new_mem_buf(data_body->data, data_body->length);
 601         else {
 602             bio = BIO_new(BIO_s_mem());
 603             BIO_set_mem_eof_return(bio, 0);
 604         }
 605         if (bio == NULL)
 606             goto err;
 607     }
 608     BIO_push(out, bio);
 609     bio = NULL;
 610     return out;
 611
 612  err:
 613     OPENSSL_clear_free(ek, eklen);
 614     OPENSSL_clear_free(tkey, tkeylen);
 615     BIO_free_all(out);
 616     BIO_free_all(btmp);
 617     BIO_free_all(etmp);
 618     BIO_free_all(bio);
 619     return  NULL;
 620 }
 621
 622 static BIO *PKCS7_find_digest(EVP_MD_CTX **pmd, BIO *bio, int nid)
 623 {
 624     for (;;) {
 625         bio = BIO_find_type(bio, BIO_TYPE_MD);
 626         if (bio == NULL) {
 627             PKCS7err(PKCS7_F_PKCS7_FIND_DIGEST,
 628                      PKCS7_R_UNABLE_TO_FIND_MESSAGE_DIGEST);
 629             return NULL;
 630         }
 631         BIO_get_md_ctx(bio, pmd);
 632         if (*pmd == NULL) {
 633             PKCS7err(PKCS7_F_PKCS7_FIND_DIGEST, ERR_R_INTERNAL_ERROR);
 634             return NULL;
 635         }
 636         if (EVP_MD_CTX_type(*pmd) == nid)
 637             return bio;
 638         bio = BIO_next(bio);
 639     }
 640     return NULL;
 641 }
 642
 643 static int do_pkcs7_signed_attrib(PKCS7_SIGNER_INFO *si, EVP_MD_CTX *mctx)
 644 {
 645     unsigned char md_data[EVP_MAX_MD_SIZE];
 646     unsigned int md_len;
 647
 648     /* Add signing time if not already present */
 649     if (!PKCS7_get_signed_attribute(si, NID_pkcs9_signingTime)) {
 650         if (!PKCS7_add0_attrib_signing_time(si, NULL)) {
 651             PKCS7err(PKCS7_F_DO_PKCS7_SIGNED_ATTRIB, ERR_R_MALLOC_FAILURE);
 652             return 0;
 653         }
 654     }
 655
 656     /* Add digest */
 657     if (!EVP_DigestFinal_ex(mctx, md_data, &md_len)) {
 658         PKCS7err(PKCS7_F_DO_PKCS7_SIGNED_ATTRIB, ERR_R_EVP_LIB);
 659         return 0;
 660     }
 661     if (!PKCS7_add1_attrib_digest(si, md_data, md_len)) {
 662         PKCS7err(PKCS7_F_DO_PKCS7_SIGNED_ATTRIB, ERR_R_MALLOC_FAILURE);
 663         return 0;
 664     }
 665
 666     /* Now sign the attributes */
 667     if (!PKCS7_SIGNER_INFO_sign(si))
 668         return 0;
 669
 670     return 1;
 671 }
 672
 673 int PKCS7_dataFinal(PKCS7 *p7, BIO *bio)
 674 {
 675     int ret = 0;
 676     int i, j;
 677     BIO *btmp;
 678     PKCS7_SIGNER_INFO *si;
 679     EVP_MD_CTX *mdc, ctx_tmp;
 680     STACK_OF(X509_ATTRIBUTE) *sk;
 681     STACK_OF(PKCS7_SIGNER_INFO) *si_sk = NULL;
 682     ASN1_OCTET_STRING *os = NULL;
 683
 684     if (p7 == NULL) {
 685         PKCS7err(PKCS7_F_PKCS7_DATAFINAL, PKCS7_R_INVALID_NULL_POINTER);
 686         return 0;
 687     }
 688
 689     if (p7->d.ptr == NULL) {
 690         PKCS7err(PKCS7_F_PKCS7_DATAFINAL, PKCS7_R_NO_CONTENT);
 691         return 0;
 692     }
 693
 694     EVP_MD_CTX_init(&ctx_tmp);
 695     i = OBJ_obj2nid(p7->type);
 696     p7->state = PKCS7_S_HEADER;
 697
 698     switch (i) {
 699     case NID_pkcs7_data:
 700         os = p7->d.data;
 701         break;
 702     case NID_pkcs7_signedAndEnveloped:
 703         /* XXXXXXXXXXXXXXXX */
 704         si_sk = p7->d.signed_and_enveloped->signer_info;
 705         os = p7->d.signed_and_enveloped->enc_data->enc_data;
 706         if (!os) {
 707             os = ASN1_OCTET_STRING_new();
 708             if (!os) {
 709                 PKCS7err(PKCS7_F_PKCS7_DATAFINAL, ERR_R_MALLOC_FAILURE);
 710                 goto err;
 711             }
 712             p7->d.signed_and_enveloped->enc_data->enc_data = os;
 713         }
 714         break;
 715     case NID_pkcs7_enveloped:
 716         /* XXXXXXXXXXXXXXXX */
 717         os = p7->d.enveloped->enc_data->enc_data;
 718         if (!os) {
 719             os = ASN1_OCTET_STRING_new();
 720             if (!os) {
 721                 PKCS7err(PKCS7_F_PKCS7_DATAFINAL, ERR_R_MALLOC_FAILURE);
 722                 goto err;
 723             }
 724             p7->d.enveloped->enc_data->enc_data = os;
 725         }
 726         break;
 727     case NID_pkcs7_signed:
 728         si_sk = p7->d.sign->signer_info;
 729         os = PKCS7_get_octet_string(p7->d.sign->contents);
 730         /* If detached data then the content is excluded */
 731         if (PKCS7_type_is_data(p7->d.sign->contents) && p7->detached) {
 732             ASN1_OCTET_STRING_free(os);
 733             os = NULL;
 734             p7->d.sign->contents->d.data = NULL;
 735         }
 736         break;
 737
 738     case NID_pkcs7_digest:
 739         os = PKCS7_get_octet_string(p7->d.digest->contents);
 740         /* If detached data then the content is excluded */
 741         if (PKCS7_type_is_data(p7->d.digest->contents) && p7->detached) {
 742             ASN1_OCTET_STRING_free(os);
 743             os = NULL;
 744             p7->d.digest->contents->d.data = NULL;
 745         }
 746         break;
 747
 748     default:
 749         PKCS7err(PKCS7_F_PKCS7_DATAFINAL, PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
 750         goto err;
 751     }
 752
 753     if (si_sk != NULL) {
 754         for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(si_sk); i++) {
 755             si = sk_PKCS7_SIGNER_INFO_value(si_sk, i);
 756             if (si->pkey == NULL)
 757                 continue;
 758
 759             j = OBJ_obj2nid(si->digest_alg->algorithm);
 760
 761             btmp = bio;
 762
 763             btmp = PKCS7_find_digest(&mdc, btmp, j);
 764
 765             if (btmp == NULL)
 766                 goto err;
 767
 768             /*
 769              * We now have the EVP_MD_CTX, lets do the signing.
 770              */
 771             if (!EVP_MD_CTX_copy_ex(&ctx_tmp, mdc))
 772                 goto err;
 773
 774             sk = si->auth_attr;
 775
 776             /*
 777              * If there are attributes, we add the digest attribute and only
 778              * sign the attributes
 779              */
 780             if (sk_X509_ATTRIBUTE_num(sk) > 0) {
 781                 if (!do_pkcs7_signed_attrib(si, &ctx_tmp))
 782                     goto err;
 783             } else {
 784                 unsigned char *abuf = NULL;
 785                 unsigned int abuflen;
 786                 abuflen = EVP_PKEY_size(si->pkey);
 787                 abuf = OPENSSL_malloc(abuflen);
 788                 if (!abuf)
 789                     goto err;
 790
 791                 if (!EVP_SignFinal(&ctx_tmp, abuf, &abuflen, si->pkey)) {
 792                     PKCS7err(PKCS7_F_PKCS7_DATAFINAL, ERR_R_EVP_LIB);
 793                     goto err;
 794                 }
 795                 ASN1_STRING_set0(si->enc_digest, abuf, abuflen);
 796             }
 797         }
 798     } else if (i == NID_pkcs7_digest) {
 799         unsigned char md_data[EVP_MAX_MD_SIZE];
 800         unsigned int md_len;
 801         if (!PKCS7_find_digest(&mdc, bio,
 802                                OBJ_obj2nid(p7->d.digest->md->algorithm)))
 803             goto err;
 804         if (!EVP_DigestFinal_ex(mdc, md_data, &md_len))
 805             goto err;
 806         ASN1_OCTET_STRING_set(p7->d.digest->digest, md_data, md_len);
 807     }
 808
 809     if (!PKCS7_is_detached(p7)) {
 810         /*
 811          * NOTE(emilia): I think we only reach os == NULL here because detached
 812          * digested data support is broken.
 813          */
 814         if (os == NULL)
 815             goto err;
 816         if (!(os->flags & ASN1_STRING_FLAG_NDEF)) {
 817             char *cont;
 818             long contlen;
 819             btmp = BIO_find_type(bio, BIO_TYPE_MEM);
 820             if (btmp == NULL) {
 821                 PKCS7err(PKCS7_F_PKCS7_DATAFINAL, PKCS7_R_UNABLE_TO_FIND_MEM_BIO);
 822                 goto err;
 823             }
 824             contlen = BIO_get_mem_data(btmp, &cont);
 825             /*
 826              * Mark the BIO read only then we can use its copy of the data
 827              * instead of making an extra copy.
 828              */
 829             BIO_set_flags(btmp, BIO_FLAGS_MEM_RDONLY);
 830             BIO_set_mem_eof_return(btmp, 0);
 831             ASN1_STRING_set0(os, (unsigned char *)cont, contlen);
 832         }
 833     }
 834     ret = 1;
 835  err:
 836     EVP_MD_CTX_cleanup(&ctx_tmp);
 837     return (ret);
 838 }
 839
 840 int PKCS7_SIGNER_INFO_sign(PKCS7_SIGNER_INFO *si)
 841 {
 842     EVP_MD_CTX mctx;
 843     EVP_PKEY_CTX *pctx;
 844     unsigned char *abuf = NULL;
 845     int alen;
 846     size_t siglen;
 847     const EVP_MD *md = NULL;
 848
 849     md = EVP_get_digestbyobj(si->digest_alg->algorithm);
 850     if (md == NULL)
 851         return 0;
 852
 853     EVP_MD_CTX_init(&mctx);
 854     if (EVP_DigestSignInit(&mctx, &pctx, md, NULL, si->pkey) <= 0)
 855         goto err;
 856
 857     if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
 858                           EVP_PKEY_CTRL_PKCS7_SIGN, 0, si) <= 0) {
 859         PKCS7err(PKCS7_F_PKCS7_SIGNER_INFO_SIGN, PKCS7_R_CTRL_ERROR);
 860         goto err;
 861     }
 862
 863     alen = ASN1_item_i2d((ASN1_VALUE *)si->auth_attr, &abuf,
 864                          ASN1_ITEM_rptr(PKCS7_ATTR_SIGN));
 865     if (!abuf)
 866         goto err;
 867     if (EVP_DigestSignUpdate(&mctx, abuf, alen) <= 0)
 868         goto err;
 869     OPENSSL_free(abuf);
 870     abuf = NULL;
 871     if (EVP_DigestSignFinal(&mctx, NULL, &siglen) <= 0)
 872         goto err;
 873     abuf = OPENSSL_malloc(siglen);
 874     if (!abuf)
 875         goto err;
 876     if (EVP_DigestSignFinal(&mctx, abuf, &siglen) <= 0)
 877         goto err;
 878
 879     if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
 880                           EVP_PKEY_CTRL_PKCS7_SIGN, 1, si) <= 0) {
 881         PKCS7err(PKCS7_F_PKCS7_SIGNER_INFO_SIGN, PKCS7_R_CTRL_ERROR);
 882         goto err;
 883     }
 884
 885     EVP_MD_CTX_cleanup(&mctx);
 886
 887     ASN1_STRING_set0(si->enc_digest, abuf, siglen);
 888
 889     return 1;
 890
 891  err:
 892     OPENSSL_free(abuf);
 893     EVP_MD_CTX_cleanup(&mctx);
 894     return 0;
 895
 896 }
 897
 898 int PKCS7_dataVerify(X509_STORE *cert_store, X509_STORE_CTX *ctx, BIO *bio,
 899                      PKCS7 *p7, PKCS7_SIGNER_INFO *si)
 900 {
 901     PKCS7_ISSUER_AND_SERIAL *ias;
 902     int ret = 0, i;
 903     STACK_OF(X509) *cert;
 904     X509 *x509;
 905
 906     if (p7 == NULL) {
 907         PKCS7err(PKCS7_F_PKCS7_DATAVERIFY, PKCS7_R_INVALID_NULL_POINTER);
 908         return 0;
 909     }
 910
 911     if (p7->d.ptr == NULL) {
 912         PKCS7err(PKCS7_F_PKCS7_DATAVERIFY, PKCS7_R_NO_CONTENT);
 913         return 0;
 914     }
 915
 916     if (PKCS7_type_is_signed(p7)) {
 917         cert = p7->d.sign->cert;
 918     } else if (PKCS7_type_is_signedAndEnveloped(p7)) {
 919         cert = p7->d.signed_and_enveloped->cert;
 920     } else {
 921         PKCS7err(PKCS7_F_PKCS7_DATAVERIFY, PKCS7_R_WRONG_PKCS7_TYPE);
 922         goto err;
 923     }
 924     /* XXXXXXXXXXXXXXXXXXXXXXX */
 925     ias = si->issuer_and_serial;
 926
 927     x509 = X509_find_by_issuer_and_serial(cert, ias->issuer, ias->serial);
 928
 929     /* were we able to find the cert in passed to us */
 930     if (x509 == NULL) {
 931         PKCS7err(PKCS7_F_PKCS7_DATAVERIFY,
 932                  PKCS7_R_UNABLE_TO_FIND_CERTIFICATE);
 933         goto err;
 934     }
 935
 936     /* Lets verify */
 937     if (!X509_STORE_CTX_init(ctx, cert_store, x509, cert)) {
 938         PKCS7err(PKCS7_F_PKCS7_DATAVERIFY, ERR_R_X509_LIB);
 939         goto err;
 940     }
 941     X509_STORE_CTX_set_purpose(ctx, X509_PURPOSE_SMIME_SIGN);
 942     i = X509_verify_cert(ctx);
 943     if (i <= 0) {
 944         PKCS7err(PKCS7_F_PKCS7_DATAVERIFY, ERR_R_X509_LIB);
 945         X509_STORE_CTX_cleanup(ctx);
 946         goto err;
 947     }
 948     X509_STORE_CTX_cleanup(ctx);
 949
 950     return PKCS7_signatureVerify(bio, p7, si, x509);
 951  err:
 952     return ret;
 953 }
 954
 955 int PKCS7_signatureVerify(BIO *bio, PKCS7 *p7, PKCS7_SIGNER_INFO *si,
 956                           X509 *x509)
 957 {
 958     ASN1_OCTET_STRING *os;
 959     EVP_MD_CTX mdc_tmp, *mdc;
 960     int ret = 0, i;
 961     int md_type;
 962     STACK_OF(X509_ATTRIBUTE) *sk;
 963     BIO *btmp;
 964     EVP_PKEY *pkey;
 965
 966     EVP_MD_CTX_init(&mdc_tmp);
 967
 968     if (!PKCS7_type_is_signed(p7) && !PKCS7_type_is_signedAndEnveloped(p7)) {
 969         PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY, PKCS7_R_WRONG_PKCS7_TYPE);
 970         goto err;
 971     }
 972
 973     md_type = OBJ_obj2nid(si->digest_alg->algorithm);
 974
 975     btmp = bio;
 976     for (;;) {
 977         if ((btmp == NULL) ||
 978             ((btmp = BIO_find_type(btmp, BIO_TYPE_MD)) == NULL)) {
 979             PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
 980                      PKCS7_R_UNABLE_TO_FIND_MESSAGE_DIGEST);
 981             goto err;
 982         }
 983         BIO_get_md_ctx(btmp, &mdc);
 984         if (mdc == NULL) {
 985             PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY, ERR_R_INTERNAL_ERROR);
 986             goto err;
 987         }
 988         if (EVP_MD_CTX_type(mdc) == md_type)
 989             break;
 990         /*
 991          * Workaround for some broken clients that put the signature OID
 992          * instead of the digest OID in digest_alg->algorithm
 993          */
 994         if (EVP_MD_pkey_type(EVP_MD_CTX_md(mdc)) == md_type)
 995             break;
 996         btmp = BIO_next(btmp);
 997     }
 998
 999     /*
1000      * mdc is the digest ctx that we want, unless there are attributes, in
1001      * which case the digest is the signed attributes
1002      */
1003     if (!EVP_MD_CTX_copy_ex(&mdc_tmp, mdc))
1004         goto err;
1005
1006     sk = si->auth_attr;
1007     if ((sk != NULL) && (sk_X509_ATTRIBUTE_num(sk) != 0)) {
1008         unsigned char md_dat[EVP_MAX_MD_SIZE], *abuf = NULL;
1009         unsigned int md_len;
1010         int alen;
1011         ASN1_OCTET_STRING *message_digest;
1012
1013         if (!EVP_DigestFinal_ex(&mdc_tmp, md_dat, &md_len))
1014             goto err;
1015         message_digest = PKCS7_digest_from_attributes(sk);
1016         if (!message_digest) {
1017             PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
1018                      PKCS7_R_UNABLE_TO_FIND_MESSAGE_DIGEST);
1019             goto err;
1020         }
1021         if ((message_digest->length != (int)md_len) ||
1022             (memcmp(message_digest->data, md_dat, md_len))) {
1023             PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY, PKCS7_R_DIGEST_FAILURE);
1024             ret = -1;
1025             goto err;
1026         }
1027
1028         if (!EVP_VerifyInit_ex(&mdc_tmp, EVP_get_digestbynid(md_type), NULL))
1029             goto err;
1030
1031         alen = ASN1_item_i2d((ASN1_VALUE *)sk, &abuf,
1032                              ASN1_ITEM_rptr(PKCS7_ATTR_VERIFY));
1033         if (alen <= 0) {
1034             PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY, ERR_R_ASN1_LIB);
1035             ret = -1;
1036             goto err;
1037         }
1038         if (!EVP_VerifyUpdate(&mdc_tmp, abuf, alen))
1039             goto err;
1040
1041         OPENSSL_free(abuf);
1042     }
1043
1044     os = si->enc_digest;
1045     pkey = X509_get_pubkey(x509);
1046     if (!pkey) {
1047         ret = -1;
1048         goto err;
1049     }
1050
1051     i = EVP_VerifyFinal(&mdc_tmp, os->data, os->length, pkey);
1052     EVP_PKEY_free(pkey);
1053     if (i <= 0) {
1054         PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY, PKCS7_R_SIGNATURE_FAILURE);
1055         ret = -1;
1056         goto err;
1057     }
1058     ret = 1;
1059  err:
1060     EVP_MD_CTX_cleanup(&mdc_tmp);
1061     return (ret);
1062 }
1063
1064 PKCS7_ISSUER_AND_SERIAL *PKCS7_get_issuer_and_serial(PKCS7 *p7, int idx)
1065 {
1066     STACK_OF(PKCS7_RECIP_INFO) *rsk;
1067     PKCS7_RECIP_INFO *ri;
1068     int i;
1069
1070     i = OBJ_obj2nid(p7->type);
1071     if (i != NID_pkcs7_signedAndEnveloped)
1072         return NULL;
1073     if (p7->d.signed_and_enveloped == NULL)
1074         return NULL;
1075     rsk = p7->d.signed_and_enveloped->recipientinfo;
1076     if (rsk == NULL)
1077         return NULL;
1078     ri = sk_PKCS7_RECIP_INFO_value(rsk, 0);
1079     if (sk_PKCS7_RECIP_INFO_num(rsk) <= idx)
1080         return (NULL);
1081     ri = sk_PKCS7_RECIP_INFO_value(rsk, idx);
1082     return (ri->issuer_and_serial);
1083 }
1084
1085 ASN1_TYPE *PKCS7_get_signed_attribute(PKCS7_SIGNER_INFO *si, int nid)
1086 {
1087     return (get_attribute(si->auth_attr, nid));
1088 }
1089
1090 ASN1_TYPE *PKCS7_get_attribute(PKCS7_SIGNER_INFO *si, int nid)
1091 {
1092     return (get_attribute(si->unauth_attr, nid));
1093 }
1094
1095 static ASN1_TYPE *get_attribute(STACK_OF(X509_ATTRIBUTE) *sk, int nid)
1096 {
1097     int idx;
1098     X509_ATTRIBUTE *xa;
1099     idx = X509at_get_attr_by_NID(sk, nid, -1);
1100     xa = X509at_get_attr(sk, idx);
1101     return X509_ATTRIBUTE_get0_type(xa, 0);
1102 }
1103
1104 ASN1_OCTET_STRING *PKCS7_digest_from_attributes(STACK_OF(X509_ATTRIBUTE) *sk)
1105 {
1106     ASN1_TYPE *astype;
1107     if ((astype = get_attribute(sk, NID_pkcs9_messageDigest)) == NULL)
1108         return NULL;
1109     return astype->value.octet_string;
1110 }
1111
1112 int PKCS7_set_signed_attributes(PKCS7_SIGNER_INFO *p7si,
1113                                 STACK_OF(X509_ATTRIBUTE) *sk)
1114 {
1115     int i;
1116
1117     sk_X509_ATTRIBUTE_pop_free(p7si->auth_attr, X509_ATTRIBUTE_free);
1118     p7si->auth_attr = sk_X509_ATTRIBUTE_dup(sk);
1119     if (p7si->auth_attr == NULL)
1120         return 0;
1121     for (i = 0; i < sk_X509_ATTRIBUTE_num(sk); i++) {
1122         if ((sk_X509_ATTRIBUTE_set(p7si->auth_attr, i,
1123                                    X509_ATTRIBUTE_dup(sk_X509_ATTRIBUTE_value
1124                                                       (sk, i))))
1125             == NULL)
1126             return (0);
1127     }
1128     return (1);
1129 }
1130
1131 int PKCS7_set_attributes(PKCS7_SIGNER_INFO *p7si,
1132                          STACK_OF(X509_ATTRIBUTE) *sk)
1133 {
1134     int i;
1135
1136     sk_X509_ATTRIBUTE_pop_free(p7si->unauth_attr, X509_ATTRIBUTE_free);
1137     p7si->unauth_attr = sk_X509_ATTRIBUTE_dup(sk);
1138     if (p7si->unauth_attr == NULL)
1139         return 0;
1140     for (i = 0; i < sk_X509_ATTRIBUTE_num(sk); i++) {
1141         if ((sk_X509_ATTRIBUTE_set(p7si->unauth_attr, i,
1142                                    X509_ATTRIBUTE_dup(sk_X509_ATTRIBUTE_value
1143                                                       (sk, i))))
1144             == NULL)
1145             return (0);
1146     }
1147     return (1);
1148 }
1149
1150 int PKCS7_add_signed_attribute(PKCS7_SIGNER_INFO *p7si, int nid, int atrtype,
1151                                void *value)
1152 {
1153     return (add_attribute(&(p7si->auth_attr), nid, atrtype, value));
1154 }
1155
1156 int PKCS7_add_attribute(PKCS7_SIGNER_INFO *p7si, int nid, int atrtype,
1157                         void *value)
1158 {
1159     return (add_attribute(&(p7si->unauth_attr), nid, atrtype, value));
1160 }
1161
1162 static int add_attribute(STACK_OF(X509_ATTRIBUTE) **sk, int nid, int atrtype,
1163                          void *value)
1164 {
1165     X509_ATTRIBUTE *attr = NULL;
1166
1167     if (*sk == NULL) {
1168         if ((*sk = sk_X509_ATTRIBUTE_new_null()) == NULL)
1169             return 0;
1170  new_attrib:
1171         if ((attr = X509_ATTRIBUTE_create(nid, atrtype, value)) == NULL)
1172             return 0;
1173         if (!sk_X509_ATTRIBUTE_push(*sk, attr)) {
1174             X509_ATTRIBUTE_free(attr);
1175             return 0;
1176         }
1177     } else {
1178         int i;
1179
1180         for (i = 0; i < sk_X509_ATTRIBUTE_num(*sk); i++) {
1181             attr = sk_X509_ATTRIBUTE_value(*sk, i);
1182             if (OBJ_obj2nid(X509_ATTRIBUTE_get0_object(attr)) == nid) {
1183                 X509_ATTRIBUTE_free(attr);
1184                 attr = X509_ATTRIBUTE_create(nid, atrtype, value);
1185                 if (attr == NULL)
1186                     return 0;
1187                 if (!sk_X509_ATTRIBUTE_set(*sk, i, attr)) {
1188                     X509_ATTRIBUTE_free(attr);
1189                     return 0;
1190                 }
1191                 goto end;
1192             }
1193         }
1194         goto new_attrib;
1195     }
1196  end:
1197     return (1);
1198 }