cms_enc.c revision 296341
1/* crypto/cms/cms_enc.c */ 2/* 3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 4 * project. 5 */ 6/* ==================================================================== 7 * Copyright (c) 2008 The OpenSSL Project. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * 21 * 3. All advertising materials mentioning features or use of this 22 * software must display the following acknowledgment: 23 * "This product includes software developed by the OpenSSL Project 24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 25 * 26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27 * endorse or promote products derived from this software without 28 * prior written permission. For written permission, please contact 29 * licensing@OpenSSL.org. 30 * 31 * 5. Products derived from this software may not be called "OpenSSL" 32 * nor may "OpenSSL" appear in their names without prior written 33 * permission of the OpenSSL Project. 34 * 35 * 6. Redistributions of any form whatsoever must retain the following 36 * acknowledgment: 37 * "This product includes software developed by the OpenSSL Project 38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51 * OF THE POSSIBILITY OF SUCH DAMAGE. 52 * ==================================================================== 53 */ 54 55#include "cryptlib.h" 56#include <openssl/asn1t.h> 57#include <openssl/pem.h> 58#include <openssl/x509v3.h> 59#include <openssl/err.h> 60#include <openssl/cms.h> 61#include <openssl/rand.h> 62#include "cms_lcl.h" 63 64/* CMS EncryptedData Utilities */ 65 66DECLARE_ASN1_ITEM(CMS_EncryptedData) 67 68/* Return BIO based on EncryptedContentInfo and key */ 69 70BIO *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 unsigned char *tkey = NULL; 78 size_t tkeylen = 0; 79 80 int ok = 0; 81 82 int enc, keep_key = 0; 83 84 enc = ec->cipher ? 1 : 0; 85 86 b = BIO_new(BIO_f_cipher()); 87 if (!b) { 88 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 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 /* 97 * If not keeping key set cipher to NULL so subsequent calls decrypt. 98 */ 99 if (ec->key) 100 ec->cipher = NULL; 101 } else { 102 ciph = EVP_get_cipherbyobj(calg->algorithm); 103 104 if (!ciph) { 105 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, CMS_R_UNKNOWN_CIPHER); 106 goto err; 107 } 108 } 109 110 if (EVP_CipherInit_ex(ctx, ciph, NULL, NULL, NULL, enc) <= 0) { 111 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 112 CMS_R_CIPHER_INITIALISATION_ERROR); 113 goto err; 114 } 115 116 if (enc) { 117 int ivlen; 118 calg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_type(ctx)); 119 /* Generate a random IV if we need one */ 120 ivlen = EVP_CIPHER_CTX_iv_length(ctx); 121 if (ivlen > 0) { 122 if (RAND_pseudo_bytes(iv, ivlen) <= 0) 123 goto err; 124 piv = iv; 125 } 126 } else if (EVP_CIPHER_asn1_to_param(ctx, calg->parameter) <= 0) { 127 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 128 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR); 129 goto err; 130 } 131 tkeylen = EVP_CIPHER_CTX_key_length(ctx); 132 /* Generate random session key */ 133 if (!enc || !ec->key) { 134 tkey = OPENSSL_malloc(tkeylen); 135 if (!tkey) { 136 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE); 137 goto err; 138 } 139 if (EVP_CIPHER_CTX_rand_key(ctx, tkey) <= 0) 140 goto err; 141 } 142 143 if (!ec->key) { 144 ec->key = tkey; 145 ec->keylen = tkeylen; 146 tkey = NULL; 147 if (enc) 148 keep_key = 1; 149 else 150 ERR_clear_error(); 151 152 } 153 154 if (ec->keylen != tkeylen) { 155 /* If necessary set key length */ 156 if (EVP_CIPHER_CTX_set_key_length(ctx, ec->keylen) <= 0) { 157 /* 158 * Only reveal failure if debugging so we don't leak information 159 * which may be useful in MMA. 160 */ 161 if (enc || ec->debug) { 162 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 163 CMS_R_INVALID_KEY_LENGTH); 164 goto err; 165 } else { 166 /* Use random key */ 167 OPENSSL_cleanse(ec->key, ec->keylen); 168 OPENSSL_free(ec->key); 169 ec->key = tkey; 170 ec->keylen = tkeylen; 171 tkey = NULL; 172 ERR_clear_error(); 173 } 174 } 175 } 176 177 if (EVP_CipherInit_ex(ctx, NULL, NULL, ec->key, piv, enc) <= 0) { 178 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 179 CMS_R_CIPHER_INITIALISATION_ERROR); 180 goto err; 181 } 182 183 if (piv) { 184 calg->parameter = ASN1_TYPE_new(); 185 if (!calg->parameter) { 186 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE); 187 goto err; 188 } 189 if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0) { 190 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, 191 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR); 192 goto err; 193 } 194 } 195 ok = 1; 196 197 err: 198 if (ec->key && !keep_key) { 199 OPENSSL_cleanse(ec->key, ec->keylen); 200 OPENSSL_free(ec->key); 201 ec->key = NULL; 202 } 203 if (tkey) { 204 OPENSSL_cleanse(tkey, tkeylen); 205 OPENSSL_free(tkey); 206 } 207 if (ok) 208 return b; 209 BIO_free(b); 210 return NULL; 211} 212 213int cms_EncryptedContent_init(CMS_EncryptedContentInfo *ec, 214 const EVP_CIPHER *cipher, 215 const unsigned char *key, size_t keylen) 216{ 217 ec->cipher = cipher; 218 if (key) { 219 ec->key = OPENSSL_malloc(keylen); 220 if (!ec->key) 221 return 0; 222 memcpy(ec->key, key, keylen); 223 } 224 ec->keylen = keylen; 225 if (cipher) 226 ec->contentType = OBJ_nid2obj(NID_pkcs7_data); 227 return 1; 228} 229 230int CMS_EncryptedData_set1_key(CMS_ContentInfo *cms, const EVP_CIPHER *ciph, 231 const unsigned char *key, size_t keylen) 232{ 233 CMS_EncryptedContentInfo *ec; 234 if (!key || !keylen) { 235 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NO_KEY); 236 return 0; 237 } 238 if (ciph) { 239 cms->d.encryptedData = M_ASN1_new_of(CMS_EncryptedData); 240 if (!cms->d.encryptedData) { 241 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, ERR_R_MALLOC_FAILURE); 242 return 0; 243 } 244 cms->contentType = OBJ_nid2obj(NID_pkcs7_encrypted); 245 cms->d.encryptedData->version = 0; 246 } else if (OBJ_obj2nid(cms->contentType) != NID_pkcs7_encrypted) { 247 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NOT_ENCRYPTED_DATA); 248 return 0; 249 } 250 ec = cms->d.encryptedData->encryptedContentInfo; 251 return cms_EncryptedContent_init(ec, ciph, key, keylen); 252} 253 254BIO *cms_EncryptedData_init_bio(CMS_ContentInfo *cms) 255{ 256 CMS_EncryptedData *enc = cms->d.encryptedData; 257 if (enc->encryptedContentInfo->cipher && enc->unprotectedAttrs) 258 enc->version = 2; 259 return cms_EncryptedContent_init_bio(enc->encryptedContentInfo); 260} 261