crypto/cms/cms_enc.c

   1 /* crypto/cms/cms_enc.c */
   2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
   3  * project.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 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@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 #include "cryptlib.h"
  55 #include <openssl/asn1t.h>
  56 #include <openssl/pem.h>
  57 #include <openssl/x509v3.h>
  58 #include <openssl/err.h>
  59 #include <openssl/cms.h>
  60 #include <openssl/rand.h>
  61 #include "cms_lcl.h"
  62 #include "asn1_locl.h"
  63
  64 /* CMS EncryptedData Utilities */
  65
  66 DECLARE_ASN1_ITEM(CMS_EncryptedData)
  67
  68 /* Return BIO based on EncryptedContentInfo and key */
  69
  70 BIO *cms_EncryptedContent_init_bio(CMS_EncryptedContentInfo *ec)
  71         {
  72         BIO *b;
  73         EVP_CIPHER_CTX *ctx;
  74         const EVP_CIPHER *ciph;
  75         X509_ALGOR *calg = ec->contentEncryptionAlgorithm;
  76         unsigned char iv[EVP_MAX_IV_LENGTH], *piv = NULL;
  77
  78         int ok = 0;
  79
  80         int enc, keep_key = 0;
  81
  82         enc = ec->cipher ? 1 : 0;
  83
  84         b = BIO_new(BIO_f_cipher());
  85         if (!b)
  86                 {
  87                 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
  88                                                         ERR_R_MALLOC_FAILURE);
  89                 return NULL;
  90                 }
  91
  92         BIO_get_cipher_ctx(b, &ctx);
  93
  94         if (enc)
  95                 ciph = ec->cipher;
  96         else
  97                 {
  98                 ciph = EVP_get_cipherbyobj(calg->algorithm);
  99
 100                 if (!ciph)
 101                         {
 102                         CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 103                                                         CMS_R_UNKNOWN_CIPHER);
 104                         goto err;
 105                         }
 106                 }
 107
 108         if (EVP_CipherInit_ex(ctx, ciph, NULL, NULL, NULL, enc) <= 0)
 109                 {
 110                 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 111                                 CMS_R_CIPHER_INITIALISATION_ERROR);
 112                 goto err;
 113                 }
 114
 115         if (enc)
 116                 calg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_type(ctx));
 117
 118         if (enc)
 119                 {
 120                 int ivlen;
 121                 /* Generate a random IV if we need one */
 122                 ivlen = EVP_CIPHER_CTX_iv_length(ctx);
 123                 if (ivlen > 0)
 124                         {
 125                         if (RAND_pseudo_bytes(iv, ivlen) <= 0)
 126                                 goto err;
 127                         piv = iv;
 128                         }
 129                 }
 130         else if (EVP_CIPHER_asn1_to_param(ctx, calg->parameter) <= 0)
 131                         {
 132                         CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 133                                 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
 134                         goto err;
 135                         }
 136
 137
 138         if (enc && !ec->key)
 139                 {
 140                 /* Generate random key */
 141                 if (!ec->keylen)
 142                         ec->keylen = EVP_CIPHER_CTX_key_length(ctx);
 143                 ec->key = OPENSSL_malloc(ec->keylen);
 144                 if (!ec->key)
 145                         {
 146                         CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 147                                                         ERR_R_MALLOC_FAILURE);
 148                         goto err;
 149                         }
 150                 if (EVP_CIPHER_CTX_rand_key(ctx, ec->key) <= 0)
 151                         goto err;
 152                 keep_key = 1;
 153                 }
 154         else if (ec->keylen != (unsigned int)EVP_CIPHER_CTX_key_length(ctx))
 155                 {
 156                 /* If necessary set key length */
 157                 if (EVP_CIPHER_CTX_set_key_length(ctx, ec->keylen) <= 0)
 158                         {
 159                         CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 160                                 CMS_R_INVALID_KEY_LENGTH);
 161                         goto err;
 162                         }
 163                 }
 164
 165         if (EVP_CipherInit_ex(ctx, NULL, NULL, ec->key, piv, enc) <= 0)
 166                 {
 167                 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 168                                 CMS_R_CIPHER_INITIALISATION_ERROR);
 169                 goto err;
 170                 }
 171
 172         if (piv)
 173                 {
 174                 calg->parameter = ASN1_TYPE_new();
 175                 if (!calg->parameter)
 176                         {
 177                         CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 178                                                         ERR_R_MALLOC_FAILURE);
 179                         goto err;
 180                         }
 181                 if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0)
 182                         {
 183                         CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
 184                                 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
 185                         goto err;
 186                         }
 187                 }
 188         ok = 1;
 189
 190         err:
 191         if (ec->key && !keep_key)
 192                 {
 193                 OPENSSL_cleanse(ec->key, ec->keylen);
 194                 OPENSSL_free(ec->key);
 195                 ec->key = NULL;
 196                 }
 197         if (ok)
 198                 return b;
 199         BIO_free(b);
 200         return NULL;
 201         }
 202
 203 static int cms_EncryptedContent_init(CMS_EncryptedContentInfo *ec,
 204                                 const EVP_CIPHER *cipher,
 205                                 const unsigned char *key, size_t keylen)
 206         {
 207         ec->cipher = cipher;
 208         if (key)
 209                 {
 210                 ec->key = OPENSSL_malloc(keylen);
 211                 if (!ec->key)
 212                         return 0;
 213                 memcpy(ec->key, key, keylen);
 214                 }
 215         ec->keylen = keylen;
 216         if (cipher)
 217                 ec->contentType = OBJ_nid2obj(NID_pkcs7_data);
 218         return 1;
 219         }
 220
 221 int CMS_EncryptedData_set1_key(CMS_ContentInfo *cms, const EVP_CIPHER *ciph,
 222                                 const unsigned char *key, size_t keylen)
 223         {
 224         CMS_EncryptedContentInfo *ec;
 225         if (!key || !keylen)
 226                 {
 227                 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NO_KEY);
 228                 return 0;
 229                 }
 230         if (ciph)
 231                 {
 232                 cms->d.encryptedData = M_ASN1_new_of(CMS_EncryptedData);
 233                 if (!cms->d.encryptedData)
 234                         {
 235                         CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY,
 236                                 ERR_R_MALLOC_FAILURE);
 237                         return 0;
 238                         }
 239                 cms->contentType = OBJ_nid2obj(NID_pkcs7_encrypted);
 240                 cms->d.encryptedData->version = 0;
 241                 }
 242         else if (OBJ_obj2nid(cms->contentType) != NID_pkcs7_encrypted)
 243                 {
 244                 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY,
 245                                                 CMS_R_NOT_ENCRYPTED_DATA);
 246                 return 0;
 247                 }
 248         ec = cms->d.encryptedData->encryptedContentInfo;
 249         return cms_EncryptedContent_init(ec, ciph, key, keylen);
 250         }
 251
 252 BIO *cms_EncryptedData_init_bio(CMS_ContentInfo *cms)
 253         {
 254         CMS_EncryptedData *enc = cms->d.encryptedData;
 255         if (enc->unprotectedAttrs)
 256                 enc->version = 2;
 257         return cms_EncryptedContent_init_bio(enc->encryptedContentInfo);
 258         }