crypto/pkcs7/pk7_smime.c

   1 /*
   2  * Written by Dr Stephen N Henson (steve@openssl.org) 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 "internal/cryptlib.h"
  63 #include <openssl/x509.h>
  64 #include <openssl/x509v3.h>
  65
  66
  67 #define BUFFERSIZE 4096
  68
  69 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si);
  70
  71 PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
  72                   BIO *data, int flags)
  73 {
  74     PKCS7 *p7;
  75     int i;
  76
  77     if ((p7 = PKCS7_new()) == NULL) {
  78         PKCS7err(PKCS7_F_PKCS7_SIGN, ERR_R_MALLOC_FAILURE);
  79         return NULL;
  80     }
  81
  82     if (!PKCS7_set_type(p7, NID_pkcs7_signed))
  83         goto err;
  84
  85     if (!PKCS7_content_new(p7, NID_pkcs7_data))
  86         goto err;
  87
  88     if (pkey && !PKCS7_sign_add_signer(p7, signcert, pkey, NULL, flags)) {
  89         PKCS7err(PKCS7_F_PKCS7_SIGN, PKCS7_R_PKCS7_ADD_SIGNER_ERROR);
  90         goto err;
  91     }
  92
  93     if (!(flags & PKCS7_NOCERTS)) {
  94         for (i = 0; i < sk_X509_num(certs); i++) {
  95             if (!PKCS7_add_certificate(p7, sk_X509_value(certs, i)))
  96                 goto err;
  97         }
  98     }
  99
 100     if (flags & PKCS7_DETACHED)
 101         PKCS7_set_detached(p7, 1);
 102
 103     if (flags & (PKCS7_STREAM | PKCS7_PARTIAL))
 104         return p7;
 105
 106     if (PKCS7_final(p7, data, flags))
 107         return p7;
 108
 109  err:
 110     PKCS7_free(p7);
 111     return NULL;
 112 }
 113
 114 int PKCS7_final(PKCS7 *p7, BIO *data, int flags)
 115 {
 116     BIO *p7bio;
 117     int ret = 0;
 118
 119     if ((p7bio = PKCS7_dataInit(p7, NULL)) == NULL) {
 120         PKCS7err(PKCS7_F_PKCS7_FINAL, ERR_R_MALLOC_FAILURE);
 121         return 0;
 122     }
 123
 124     SMIME_crlf_copy(data, p7bio, flags);
 125
 126     (void)BIO_flush(p7bio);
 127
 128     if (!PKCS7_dataFinal(p7, p7bio)) {
 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 static int add_digest_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
 152 {
 153     if (EVP_get_digestbynid(nid))
 154         return PKCS7_simple_smimecap(sk, nid, arg);
 155     return 1;
 156 }
 157
 158 PKCS7_SIGNER_INFO *PKCS7_sign_add_signer(PKCS7 *p7, X509 *signcert,
 159                                          EVP_PKEY *pkey, const EVP_MD *md,
 160                                          int flags)
 161 {
 162     PKCS7_SIGNER_INFO *si = NULL;
 163     STACK_OF(X509_ALGOR) *smcap = NULL;
 164     if (!X509_check_private_key(signcert, pkey)) {
 165         PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
 166                  PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
 167         return NULL;
 168     }
 169
 170     if ((si = PKCS7_add_signature(p7, signcert, pkey, md)) == NULL) {
 171         PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
 172                  PKCS7_R_PKCS7_ADD_SIGNATURE_ERROR);
 173         return NULL;
 174     }
 175
 176     if (!(flags & PKCS7_NOCERTS)) {
 177         if (!PKCS7_add_certificate(p7, signcert))
 178             goto err;
 179     }
 180
 181     if (!(flags & PKCS7_NOATTR)) {
 182         if (!PKCS7_add_attrib_content_type(si, NULL))
 183             goto err;
 184         /* Add SMIMECapabilities */
 185         if (!(flags & PKCS7_NOSMIMECAP)) {
 186             if ((smcap = sk_X509_ALGOR_new_null()) == NULL) {
 187                 PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER, ERR_R_MALLOC_FAILURE);
 188                 goto err;
 189             }
 190             if (!add_cipher_smcap(smcap, NID_aes_256_cbc, -1)
 191                 || !add_digest_smcap(smcap, NID_id_GostR3411_2012_256, -1)
 192                 || !add_digest_smcap(smcap, NID_id_GostR3411_2012_512, -1)
 193                 || !add_digest_smcap(smcap, NID_id_GostR3411_94, -1)
 194                 || !add_cipher_smcap(smcap, NID_id_Gost28147_89, -1)
 195                 || !add_cipher_smcap(smcap, NID_aes_192_cbc, -1)
 196                 || !add_cipher_smcap(smcap, NID_aes_128_cbc, -1)
 197                 || !add_cipher_smcap(smcap, NID_des_ede3_cbc, -1)
 198                 || !add_cipher_smcap(smcap, NID_rc2_cbc, 128)
 199                 || !add_cipher_smcap(smcap, NID_rc2_cbc, 64)
 200                 || !add_cipher_smcap(smcap, NID_des_cbc, -1)
 201                 || !add_cipher_smcap(smcap, NID_rc2_cbc, 40)
 202                 || !PKCS7_add_attrib_smimecap(si, smcap))
 203                 goto err;
 204             sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
 205             smcap = NULL;
 206         }
 207         if (flags & PKCS7_REUSE_DIGEST) {
 208             if (!pkcs7_copy_existing_digest(p7, si))
 209                 goto err;
 210             if (!(flags & PKCS7_PARTIAL) && !PKCS7_SIGNER_INFO_sign(si))
 211                 goto err;
 212         }
 213     }
 214     return si;
 215  err:
 216     sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
 217     return NULL;
 218 }
 219
 220 /*
 221  * Search for a digest matching SignerInfo digest type and if found copy
 222  * across.
 223  */
 224
 225 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
 226 {
 227     int i;
 228     STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
 229     PKCS7_SIGNER_INFO *sitmp;
 230     ASN1_OCTET_STRING *osdig = NULL;
 231     sinfos = PKCS7_get_signer_info(p7);
 232     for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
 233         sitmp = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
 234         if (si == sitmp)
 235             break;
 236         if (sk_X509_ATTRIBUTE_num(sitmp->auth_attr) <= 0)
 237             continue;
 238         if (!OBJ_cmp(si->digest_alg->algorithm, sitmp->digest_alg->algorithm)) {
 239             osdig = PKCS7_digest_from_attributes(sitmp->auth_attr);
 240             break;
 241         }
 242
 243     }
 244
 245     if (osdig)
 246         return PKCS7_add1_attrib_digest(si, osdig->data, osdig->length);
 247
 248     PKCS7err(PKCS7_F_PKCS7_COPY_EXISTING_DIGEST,
 249              PKCS7_R_NO_MATCHING_DIGEST_TYPE_FOUND);
 250     return 0;
 251 }
 252
 253 int PKCS7_verify(PKCS7 *p7, STACK_OF(X509) *certs, X509_STORE *store,
 254                  BIO *indata, BIO *out, int flags)
 255 {
 256     STACK_OF(X509) *signers;
 257     X509 *signer;
 258     STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
 259     PKCS7_SIGNER_INFO *si;
 260     X509_STORE_CTX *cert_ctx = NULL;
 261     char *buf = NULL;
 262     int i, j = 0, k, ret = 0;
 263     BIO *p7bio = NULL;
 264     BIO *tmpin = NULL, *tmpout = NULL;
 265
 266     if (!p7) {
 267         PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_INVALID_NULL_POINTER);
 268         return 0;
 269     }
 270
 271     if (!PKCS7_type_is_signed(p7)) {
 272         PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_WRONG_CONTENT_TYPE);
 273         return 0;
 274     }
 275
 276     /* Check for no data and no content: no data to verify signature */
 277     if (PKCS7_get_detached(p7) && !indata) {
 278         PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_CONTENT);
 279         return 0;
 280     }
 281
 282     if (flags & PKCS7_NO_DUAL_CONTENT) {
 283         /*
 284          * This was originally "#if 0" because we thought that only old broken
 285          * Netscape did this.  It turns out that Authenticode uses this kind
 286          * of "extended" PKCS7 format, and things like UEFI secure boot and
 287          * tools like osslsigncode need it.  In Authenticode the verification
 288          * process is different, but the existing PKCs7 verification works.
 289          */
 290         if (!PKCS7_get_detached(p7) && indata) {
 291             PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_CONTENT_AND_DATA_PRESENT);
 292             return 0;
 293         }
 294     }
 295
 296     sinfos = PKCS7_get_signer_info(p7);
 297
 298     if (!sinfos || !sk_PKCS7_SIGNER_INFO_num(sinfos)) {
 299         PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_SIGNATURES_ON_DATA);
 300         return 0;
 301     }
 302
 303     signers = PKCS7_get0_signers(p7, certs, flags);
 304     if (!signers)
 305         return 0;
 306
 307     /* Now verify the certificates */
 308
 309     cert_ctx = X509_STORE_CTX_new();
 310     if (cert_ctx == NULL)
 311         goto err;
 312     if (!(flags & PKCS7_NOVERIFY))
 313         for (k = 0; k < sk_X509_num(signers); k++) {
 314             signer = sk_X509_value(signers, k);
 315             if (!(flags & PKCS7_NOCHAIN)) {
 316                 if (!X509_STORE_CTX_init(cert_ctx, store, signer,
 317                                          p7->d.sign->cert)) {
 318                     PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
 319                     goto err;
 320                 }
 321                 X509_STORE_CTX_set_default(cert_ctx, "smime_sign");
 322             } else if (!X509_STORE_CTX_init(cert_ctx, store, signer, NULL)) {
 323                 PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
 324                 goto err;
 325             }
 326             if (!(flags & PKCS7_NOCRL))
 327                 X509_STORE_CTX_set0_crls(cert_ctx, p7->d.sign->crl);
 328             i = X509_verify_cert(cert_ctx);
 329             if (i <= 0)
 330                 j = X509_STORE_CTX_get_error(cert_ctx);
 331             if (i <= 0) {
 332                 PKCS7err(PKCS7_F_PKCS7_VERIFY,
 333                          PKCS7_R_CERTIFICATE_VERIFY_ERROR);
 334                 ERR_add_error_data(2, "Verify error:",
 335                                    X509_verify_cert_error_string(j));
 336                 goto err;
 337             }
 338             /* Check for revocation status here */
 339         }
 340
 341     /*
 342      * Performance optimization: if the content is a memory BIO then store
 343      * its contents in a temporary read only memory BIO. This avoids
 344      * potentially large numbers of slow copies of data which will occur when
 345      * reading from a read write memory BIO when signatures are calculated.
 346      */
 347
 348     if (indata && (BIO_method_type(indata) == BIO_TYPE_MEM)) {
 349         char *ptr;
 350         long len;
 351         len = BIO_get_mem_data(indata, &ptr);
 352         tmpin = BIO_new_mem_buf(ptr, len);
 353         if (tmpin == NULL) {
 354             PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
 355             goto err;
 356         }
 357     } else
 358         tmpin = indata;
 359
 360     if ((p7bio = PKCS7_dataInit(p7, tmpin)) == NULL)
 361         goto err;
 362
 363     if (flags & PKCS7_TEXT) {
 364         if ((tmpout = BIO_new(BIO_s_mem())) == NULL) {
 365             PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
 366             goto err;
 367         }
 368         BIO_set_mem_eof_return(tmpout, 0);
 369     } else
 370         tmpout = out;
 371
 372     /* We now have to 'read' from p7bio to calculate digests etc. */
 373     if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
 374         PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
 375         goto err;
 376     }
 377     for (;;) {
 378         i = BIO_read(p7bio, buf, BUFFERSIZE);
 379         if (i <= 0)
 380             break;
 381         if (tmpout)
 382             BIO_write(tmpout, buf, i);
 383     }
 384
 385     if (flags & PKCS7_TEXT) {
 386         if (!SMIME_text(tmpout, out)) {
 387             PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SMIME_TEXT_ERROR);
 388             BIO_free(tmpout);
 389             goto err;
 390         }
 391         BIO_free(tmpout);
 392     }
 393
 394     /* Now Verify All Signatures */
 395     if (!(flags & PKCS7_NOSIGS))
 396         for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
 397             si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
 398             signer = sk_X509_value(signers, i);
 399             j = PKCS7_signatureVerify(p7bio, p7, si, signer);
 400             if (j <= 0) {
 401                 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SIGNATURE_FAILURE);
 402                 goto err;
 403             }
 404         }
 405
 406     ret = 1;
 407
 408  err:
 409     X509_STORE_CTX_free(cert_ctx);
 410     OPENSSL_free(buf);
 411     if (tmpin == indata) {
 412         if (indata)
 413             BIO_pop(p7bio);
 414     }
 415     BIO_free_all(p7bio);
 416     sk_X509_free(signers);
 417     return ret;
 418 }
 419
 420 STACK_OF(X509) *PKCS7_get0_signers(PKCS7 *p7, STACK_OF(X509) *certs,
 421                                    int flags)
 422 {
 423     STACK_OF(X509) *signers;
 424     STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
 425     PKCS7_SIGNER_INFO *si;
 426     PKCS7_ISSUER_AND_SERIAL *ias;
 427     X509 *signer;
 428     int i;
 429
 430     if (!p7) {
 431         PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_INVALID_NULL_POINTER);
 432         return NULL;
 433     }
 434
 435     if (!PKCS7_type_is_signed(p7)) {
 436         PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_WRONG_CONTENT_TYPE);
 437         return NULL;
 438     }
 439
 440     /* Collect all the signers together */
 441
 442     sinfos = PKCS7_get_signer_info(p7);
 443
 444     if (sk_PKCS7_SIGNER_INFO_num(sinfos) <= 0) {
 445         PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_NO_SIGNERS);
 446         return 0;
 447     }
 448
 449     if ((signers = sk_X509_new_null()) == NULL) {
 450         PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, ERR_R_MALLOC_FAILURE);
 451         return NULL;
 452     }
 453
 454     for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
 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)
 460             signer = X509_find_by_issuer_and_serial(certs,
 461                                                     ias->issuer, ias->serial);
 462         if (!signer && !(flags & PKCS7_NOINTERN)
 463             && p7->d.sign->cert)
 464             signer =
 465                 X509_find_by_issuer_and_serial(p7->d.sign->cert,
 466                                                ias->issuer, ias->serial);
 467         if (!signer) {
 468             PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,
 469                      PKCS7_R_SIGNER_CERTIFICATE_NOT_FOUND);
 470             sk_X509_free(signers);
 471             return 0;
 472         }
 473
 474         if (!sk_X509_push(signers, signer)) {
 475             sk_X509_free(signers);
 476             return NULL;
 477         }
 478     }
 479     return signers;
 480 }
 481
 482 /* Build a complete PKCS#7 enveloped data */
 483
 484 PKCS7 *PKCS7_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher,
 485                      int flags)
 486 {
 487     PKCS7 *p7;
 488     BIO *p7bio = NULL;
 489     int i;
 490     X509 *x509;
 491     if ((p7 = PKCS7_new()) == NULL) {
 492         PKCS7err(PKCS7_F_PKCS7_ENCRYPT, ERR_R_MALLOC_FAILURE);
 493         return NULL;
 494     }
 495
 496     if (!PKCS7_set_type(p7, NID_pkcs7_enveloped))
 497         goto err;
 498     if (!PKCS7_set_cipher(p7, cipher)) {
 499         PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_SETTING_CIPHER);
 500         goto err;
 501     }
 502
 503     for (i = 0; i < sk_X509_num(certs); i++) {
 504         x509 = sk_X509_value(certs, i);
 505         if (!PKCS7_add_recipient(p7, x509)) {
 506             PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_ADDING_RECIPIENT);
 507             goto err;
 508         }
 509     }
 510
 511     if (flags & PKCS7_STREAM)
 512         return p7;
 513
 514     if (PKCS7_final(p7, in, flags))
 515         return p7;
 516
 517  err:
 518
 519     BIO_free_all(p7bio);
 520     PKCS7_free(p7);
 521     return NULL;
 522
 523 }
 524
 525 int PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
 526 {
 527     BIO *tmpmem;
 528     int ret = 0, i;
 529     char *buf = NULL;
 530
 531     if (!p7) {
 532         PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_INVALID_NULL_POINTER);
 533         return 0;
 534     }
 535
 536     if (!PKCS7_type_is_enveloped(p7)) {
 537         PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_WRONG_CONTENT_TYPE);
 538         return 0;
 539     }
 540
 541     if (cert && !X509_check_private_key(cert, pkey)) {
 542         PKCS7err(PKCS7_F_PKCS7_DECRYPT,
 543                  PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
 544         return 0;
 545     }
 546
 547     if ((tmpmem = PKCS7_dataDecode(p7, pkey, NULL, cert)) == NULL) {
 548         PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_DECRYPT_ERROR);
 549         return 0;
 550     }
 551
 552     if (flags & PKCS7_TEXT) {
 553         BIO *tmpbuf, *bread;
 554         /* Encrypt BIOs can't do BIO_gets() so add a buffer BIO */
 555         if ((tmpbuf = BIO_new(BIO_f_buffer())) == NULL) {
 556             PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
 557             BIO_free_all(tmpmem);
 558             return 0;
 559         }
 560         if ((bread = BIO_push(tmpbuf, tmpmem)) == NULL) {
 561             PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
 562             BIO_free_all(tmpbuf);
 563             BIO_free_all(tmpmem);
 564             return 0;
 565         }
 566         ret = SMIME_text(bread, data);
 567         if (ret > 0 && BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
 568             if (!BIO_get_cipher_status(tmpmem))
 569                 ret = 0;
 570         }
 571         BIO_free_all(bread);
 572         return ret;
 573     }
 574     if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
 575         PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
 576         goto err;
 577     }
 578     for (;;) {
 579         i = BIO_read(tmpmem, buf, BUFFERSIZE);
 580         if (i <= 0) {
 581             ret = 1;
 582             if (BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
 583                 if (!BIO_get_cipher_status(tmpmem))
 584                     ret = 0;
 585             }
 586
 587             break;
 588         }
 589         if (BIO_write(data, buf, i) != i) {
 590             break;
 591         }
 592     }
 593 err:
 594     OPENSSL_free(buf);
 595     BIO_free_all(tmpmem);
 596     return ret;
 597 }