2 * Copyright 2008-2020 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 #include "internal/cryptlib.h"
11 #include <openssl/asn1t.h>
12 #include <openssl/pem.h>
13 #include <openssl/x509v3.h>
14 #include <openssl/err.h>
15 #include <openssl/cms.h>
16 #include <openssl/rand.h>
17 #include "cms_local.h"
19 /* CMS EncryptedData Utilities */
21 /* Return BIO based on EncryptedContentInfo and key */
23 BIO *cms_EncryptedContent_init_bio(CMS_EncryptedContentInfo *ec,
24 const CMS_CTX *cms_ctx)
28 EVP_CIPHER *fetched_ciph = NULL;
29 const EVP_CIPHER *cipher = NULL;
30 X509_ALGOR *calg = ec->contentEncryptionAlgorithm;
31 unsigned char iv[EVP_MAX_IV_LENGTH], *piv = NULL;
32 unsigned char *tkey = NULL;
36 int enc, keep_key = 0;
38 enc = ec->cipher ? 1 : 0;
40 b = BIO_new(BIO_f_cipher());
42 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
46 BIO_get_cipher_ctx(b, &ctx);
51 * If not keeping key set cipher to NULL so subsequent calls decrypt.
56 cipher = EVP_get_cipherbyobj(calg->algorithm);
59 fetched_ciph = EVP_CIPHER_fetch(cms_ctx->libctx, EVP_CIPHER_name(cipher),
61 if (fetched_ciph == NULL) {
62 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, CMS_R_UNKNOWN_CIPHER);
66 if (EVP_CipherInit_ex(ctx, fetched_ciph, NULL, NULL, NULL, enc) <= 0) {
67 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
68 CMS_R_CIPHER_INITIALISATION_ERROR);
71 EVP_CIPHER_free(fetched_ciph);
75 calg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_type(ctx));
76 /* Generate a random IV if we need one */
77 ivlen = EVP_CIPHER_CTX_iv_length(ctx);
79 if (RAND_bytes_ex(cms_ctx->libctx, iv, ivlen) <= 0)
83 } else if (EVP_CIPHER_asn1_to_param(ctx, calg->parameter) <= 0) {
84 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
85 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
88 len = EVP_CIPHER_CTX_key_length(ctx);
91 tkeylen = (size_t)len;
93 /* Generate random session key */
94 if (!enc || !ec->key) {
95 tkey = OPENSSL_malloc(tkeylen);
97 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
100 if (EVP_CIPHER_CTX_rand_key(ctx, tkey) <= 0)
106 ec->keylen = tkeylen;
115 if (ec->keylen != tkeylen) {
116 /* If necessary set key length */
117 if (EVP_CIPHER_CTX_set_key_length(ctx, ec->keylen) <= 0) {
119 * Only reveal failure if debugging so we don't leak information
120 * which may be useful in MMA.
122 if (enc || ec->debug) {
123 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
124 CMS_R_INVALID_KEY_LENGTH);
128 OPENSSL_clear_free(ec->key, ec->keylen);
130 ec->keylen = tkeylen;
137 if (EVP_CipherInit_ex(ctx, NULL, NULL, ec->key, piv, enc) <= 0) {
138 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
139 CMS_R_CIPHER_INITIALISATION_ERROR);
143 calg->parameter = ASN1_TYPE_new();
144 if (calg->parameter == NULL) {
145 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
148 if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0) {
149 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
150 CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
153 /* If parameter type not set omit parameter */
154 if (calg->parameter->type == V_ASN1_UNDEF) {
155 ASN1_TYPE_free(calg->parameter);
156 calg->parameter = NULL;
162 if (!keep_key || !ok) {
163 OPENSSL_clear_free(ec->key, ec->keylen);
166 OPENSSL_clear_free(tkey, tkeylen);
173 int cms_EncryptedContent_init(CMS_EncryptedContentInfo *ec,
174 const EVP_CIPHER *cipher,
175 const unsigned char *key, size_t keylen,
176 const CMS_CTX *cms_ctx)
180 if ((ec->key = OPENSSL_malloc(keylen)) == NULL) {
181 CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT, ERR_R_MALLOC_FAILURE);
184 memcpy(ec->key, key, keylen);
188 ec->contentType = OBJ_nid2obj(NID_pkcs7_data);
192 int CMS_EncryptedData_set1_key(CMS_ContentInfo *cms, const EVP_CIPHER *ciph,
193 const unsigned char *key, size_t keylen)
195 CMS_EncryptedContentInfo *ec;
197 if (!key || !keylen) {
198 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NO_KEY);
202 cms->d.encryptedData = M_ASN1_new_of(CMS_EncryptedData);
203 if (!cms->d.encryptedData) {
204 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, ERR_R_MALLOC_FAILURE);
207 cms->contentType = OBJ_nid2obj(NID_pkcs7_encrypted);
208 cms->d.encryptedData->version = 0;
209 } else if (OBJ_obj2nid(cms->contentType) != NID_pkcs7_encrypted) {
210 CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NOT_ENCRYPTED_DATA);
213 ec = cms->d.encryptedData->encryptedContentInfo;
214 return cms_EncryptedContent_init(ec, ciph, key, keylen, cms_get0_cmsctx(cms));
217 BIO *cms_EncryptedData_init_bio(const CMS_ContentInfo *cms)
219 CMS_EncryptedData *enc = cms->d.encryptedData;
220 if (enc->encryptedContentInfo->cipher && enc->unprotectedAttrs)
222 return cms_EncryptedContent_init_bio(enc->encryptedContentInfo,
223 cms_get0_cmsctx(cms));