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
DECLARE_ASN1_ITEM(CMS_EncryptedData)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 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
cms_EncryptedContent_init(CMS_EncryptedContentInfo * ec,const EVP_CIPHER * cipher,const unsigned char * key,size_t keylen)213 int 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
CMS_EncryptedData_set1_key(CMS_ContentInfo * cms,const EVP_CIPHER * ciph,const unsigned char * key,size_t keylen)230 int 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
cms_EncryptedData_init_bio(CMS_ContentInfo * cms)254 BIO *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