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 unsigned char *tkey = NULL;
77 size_t tkeylen = 0;
78
79 int ok = 0;
80
81 int enc, keep_key = 0;
82
83 enc = ec->cipher ? 1 : 0;
84
85 b = BIO_new(BIO_f_cipher());
86 if (!b)
87 {
88 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
89 ERR_R_MALLOC_FAILURE);
90 return NULL;
91 }
92
93 BIO_get_cipher_ctx(b, &ctx);
94
95 if (enc)
96 {
97 ciph = ec->cipher;
98 /* If not keeping key set cipher to NULL so subsequent calls
99 * decrypt.
100 */
101 if (ec->key)
102 ec->cipher = NULL;
103 }
104 else
105 {
106 ciph = EVP_get_cipherbyobj(calg->algorithm);
107
108 if (!ciph)
109 {
110 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
111 CMS_R_UNKNOWN_CIPHER);
112 goto err;
113 }
114 }
115
116 if (EVP_CipherInit_ex(ctx, ciph, NULL, NULL, NULL, enc) <= 0)
117 {
118 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
119 CMS_R_CIPHER_INITIALISATION_ERROR);
120 goto err;
121 }
122
123 if (enc)
124 {
125 int ivlen;
126 calg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_type(ctx));
127 /* Generate a random IV if we need one */
128 ivlen = EVP_CIPHER_CTX_iv_length(ctx);
129 if (ivlen > 0)
130 {
131 if (RAND_pseudo_bytes(iv, ivlen) <= 0)
132 goto err;
133 piv = iv;
134 }
135 }
136 else if (EVP_CIPHER_asn1_to_param(ctx, calg->parameter) <= 0)
137 {
138 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
139 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
140 goto err;
141 }
142 tkeylen = EVP_CIPHER_CTX_key_length(ctx);
143 /* Generate random session key */
144 if (!enc || !ec->key)
145 {
146 tkey = OPENSSL_malloc(tkeylen);
147 if (!tkey)
148 {
149 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
150 ERR_R_MALLOC_FAILURE);
151 goto err;
152 }
153 if (EVP_CIPHER_CTX_rand_key(ctx, tkey) <= 0)
154 goto err;
155 }
156
157 if (!ec->key)
158 {
159 ec->key = tkey;
160 ec->keylen = tkeylen;
161 tkey = NULL;
162 if (enc)
163 keep_key = 1;
164 else
165 ERR_clear_error();
166
167 }
168
169 if (ec->keylen != tkeylen)
170 {
171 /* If necessary set key length */
172 if (EVP_CIPHER_CTX_set_key_length(ctx, ec->keylen) <= 0)
173 {
174 /* Only reveal failure if debugging so we don't
175 * leak information which may be useful in MMA.
176 */
177 if (enc || ec->debug)
178 {
179 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
180 CMS_R_INVALID_KEY_LENGTH);
181 goto err;
182 }
183 else
184 {
185 /* Use random key */
186 OPENSSL_cleanse(ec->key, ec->keylen);
187 OPENSSL_free(ec->key);
188 ec->key = tkey;
189 ec->keylen = tkeylen;
190 tkey = NULL;
191 ERR_clear_error();
192 }
193 }
194 }
195
196 if (EVP_CipherInit_ex(ctx, NULL, NULL, ec->key, piv, enc) <= 0)
197 {
198 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
199 CMS_R_CIPHER_INITIALISATION_ERROR);
200 goto err;
201 }
202
203 if (piv)
204 {
205 calg->parameter = ASN1_TYPE_new();
206 if (!calg->parameter)
207 {
208 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
209 ERR_R_MALLOC_FAILURE);
210 goto err;
211 }
212 if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0)
213 {
214 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
215 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
216 goto err;
217 }
218 }
219 ok = 1;
220
221 err:
222 if (ec->key && !keep_key)
223 {
224 OPENSSL_cleanse(ec->key, ec->keylen);
225 OPENSSL_free(ec->key);
226 ec->key = NULL;
227 }
228 if (tkey)
229 {
230 OPENSSL_cleanse(tkey, tkeylen);
231 OPENSSL_free(tkey);
232 }
233 if (ok)
234 return b;
235 BIO_free(b);
236 return NULL;
237 }
238
239 int cms_EncryptedContent_init(CMS_EncryptedContentInfo *ec,
240 const EVP_CIPHER *cipher,
241 const unsigned char *key, size_t keylen)
242 {
243 ec->cipher = cipher;
244 if (key)
245 {
246 ec->key = OPENSSL_malloc(keylen);
247 if (!ec->key)
248 return 0;
249 memcpy(ec->key, key, keylen);
250 }
251 ec->keylen = keylen;
252 if (cipher)
253 ec->contentType = OBJ_nid2obj(NID_pkcs7_data);
254 return 1;
255 }
256
257 int CMS_EncryptedData_set1_key(CMS_ContentInfo *cms, const EVP_CIPHER *ciph,
258 const unsigned char *key, size_t keylen)
259 {
260 CMS_EncryptedContentInfo *ec;
261 if (!key || !keylen)
262 {
263 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NO_KEY);
264 return 0;
265 }
266 if (ciph)
267 {
268 cms->d.encryptedData = M_ASN1_new_of(CMS_EncryptedData);
269 if (!cms->d.encryptedData)
270 {
271 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY,
272 ERR_R_MALLOC_FAILURE);
273 return 0;
274 }
275 cms->contentType = OBJ_nid2obj(NID_pkcs7_encrypted);
276 cms->d.encryptedData->version = 0;
277 }
278 else if (OBJ_obj2nid(cms->contentType) != NID_pkcs7_encrypted)
279 {
280 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY,
281 CMS_R_NOT_ENCRYPTED_DATA);
282 return 0;
283 }
284 ec = cms->d.encryptedData->encryptedContentInfo;
285 return cms_EncryptedContent_init(ec, ciph, key, keylen);
286 }
287
288 BIO *cms_EncryptedData_init_bio(CMS_ContentInfo *cms)
289 {
290 CMS_EncryptedData *enc = cms->d.encryptedData;
291 if (enc->encryptedContentInfo->cipher && enc->unprotectedAttrs)
292 enc->version = 2;
293 return cms_EncryptedContent_init_bio(enc->encryptedContentInfo);
294 }