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 63 /* CMS EncryptedData Utilities */ 64 65 DECLARE_ASN1_ITEM(CMS_EncryptedData) 66 67 /* Return BIO based on EncryptedContentInfo and key */ 68 69 BIO *cms_EncryptedContent_init_bio(CMS_EncryptedContentInfo *ec) 70 { 71 BIO *b; 72 EVP_CIPHER_CTX *ctx; 73 const EVP_CIPHER *ciph; 74 X509_ALGOR *calg = ec->contentEncryptionAlgorithm; 75 unsigned char iv[EVP_MAX_IV_LENGTH], *piv = NULL; 76 77 int ok = 0; 78 79 int enc, keep_key = 0; 80 81 enc = ec->cipher ? 1 : 0; 82 83 b = BIO_new(BIO_f_cipher()); 84 if (!b) 85 { 86 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 87 ERR_R_MALLOC_FAILURE); 88 return NULL; 89 } 90 91 BIO_get_cipher_ctx(b, &ctx); 92 93 if (enc) 94 { 95 ciph = ec->cipher; 96 /* If not keeping key set cipher to NULL so subsequent calls 97 * decrypt. 98 */ 99 if (ec->key) 100 ec->cipher = NULL; 101 } 102 else 103 { 104 ciph = EVP_get_cipherbyobj(calg->algorithm); 105 106 if (!ciph) 107 { 108 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 109 CMS_R_UNKNOWN_CIPHER); 110 goto err; 111 } 112 } 113 114 if (EVP_CipherInit_ex(ctx, ciph, NULL, NULL, NULL, enc) <= 0) 115 { 116 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 117 CMS_R_CIPHER_INITIALISATION_ERROR); 118 goto err; 119 } 120 121 if (enc) 122 { 123 int ivlen; 124 calg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_type(ctx)); 125 /* Generate a random IV if we need one */ 126 ivlen = EVP_CIPHER_CTX_iv_length(ctx); 127 if (ivlen > 0) 128 { 129 if (RAND_pseudo_bytes(iv, ivlen) <= 0) 130 goto err; 131 piv = iv; 132 } 133 } 134 else if (EVP_CIPHER_asn1_to_param(ctx, calg->parameter) <= 0) 135 { 136 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 137 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR); 138 goto err; 139 } 140 141 142 if (enc && !ec->key) 143 { 144 /* Generate random key */ 145 if (!ec->keylen) 146 ec->keylen = EVP_CIPHER_CTX_key_length(ctx); 147 ec->key = OPENSSL_malloc(ec->keylen); 148 if (!ec->key) 149 { 150 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 151 ERR_R_MALLOC_FAILURE); 152 goto err; 153 } 154 if (EVP_CIPHER_CTX_rand_key(ctx, ec->key) <= 0) 155 goto err; 156 keep_key = 1; 157 } 158 else if (ec->keylen != (unsigned int)EVP_CIPHER_CTX_key_length(ctx)) 159 { 160 /* If necessary set key length */ 161 if (EVP_CIPHER_CTX_set_key_length(ctx, ec->keylen) <= 0) 162 { 163 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 164 CMS_R_INVALID_KEY_LENGTH); 165 goto err; 166 } 167 } 168 169 if (EVP_CipherInit_ex(ctx, NULL, NULL, ec->key, piv, enc) <= 0) 170 { 171 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 172 CMS_R_CIPHER_INITIALISATION_ERROR); 173 goto err; 174 } 175 176 if (piv) 177 { 178 calg->parameter = ASN1_TYPE_new(); 179 if (!calg->parameter) 180 { 181 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 182 ERR_R_MALLOC_FAILURE); 183 goto err; 184 } 185 if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0) 186 { 187 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 188 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR); 189 goto err; 190 } 191 } 192 ok = 1; 193 194 err: 195 if (ec->key && !keep_key) 196 { 197 OPENSSL_cleanse(ec->key, ec->keylen); 198 OPENSSL_free(ec->key); 199 ec->key = NULL; 200 } 201 if (ok) 202 return b; 203 BIO_free(b); 204 return NULL; 205 } 206 207 int cms_EncryptedContent_init(CMS_EncryptedContentInfo *ec, 208 const EVP_CIPHER *cipher, 209 const unsigned char *key, size_t keylen) 210 { 211 ec->cipher = cipher; 212 if (key) 213 { 214 ec->key = OPENSSL_malloc(keylen); 215 if (!ec->key) 216 return 0; 217 memcpy(ec->key, key, keylen); 218 } 219 ec->keylen = keylen; 220 if (cipher) 221 ec->contentType = OBJ_nid2obj(NID_pkcs7_data); 222 return 1; 223 } 224 225 int CMS_EncryptedData_set1_key(CMS_ContentInfo *cms, const EVP_CIPHER *ciph, 226 const unsigned char *key, size_t keylen) 227 { 228 CMS_EncryptedContentInfo *ec; 229 if (!key || !keylen) 230 { 231 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NO_KEY); 232 return 0; 233 } 234 if (ciph) 235 { 236 cms->d.encryptedData = M_ASN1_new_of(CMS_EncryptedData); 237 if (!cms->d.encryptedData) 238 { 239 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, 240 ERR_R_MALLOC_FAILURE); 241 return 0; 242 } 243 cms->contentType = OBJ_nid2obj(NID_pkcs7_encrypted); 244 cms->d.encryptedData->version = 0; 245 } 246 else if (OBJ_obj2nid(cms->contentType) != NID_pkcs7_encrypted) 247 { 248 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, 249 CMS_R_NOT_ENCRYPTED_DATA); 250 return 0; 251 } 252 ec = cms->d.encryptedData->encryptedContentInfo; 253 return cms_EncryptedContent_init(ec, ciph, key, keylen); 254 } 255 256 BIO *cms_EncryptedData_init_bio(CMS_ContentInfo *cms) 257 { 258 CMS_EncryptedData *enc = cms->d.encryptedData; 259 if (enc->encryptedContentInfo->cipher && enc->unprotectedAttrs) 260 enc->version = 2; 261 return cms_EncryptedContent_init_bio(enc->encryptedContentInfo); 262 } 263