1 /* crypto/cms/cms_kari.c */
3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
6 /* ====================================================================
7 * Copyright (c) 2013 The OpenSSL Project. All rights reserved.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
35 * 6. Redistributions of any form whatsoever must retain the following
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
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 * ====================================================================
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 <openssl/aes.h>
64 #include "internal/asn1_int.h"
66 DECLARE_ASN1_ITEM(CMS_KeyAgreeRecipientInfo
)
67 DECLARE_ASN1_ITEM(CMS_RecipientEncryptedKey
)
68 DECLARE_ASN1_ITEM(CMS_OriginatorPublicKey
)
70 /* Key Agreement Recipient Info (KARI) routines */
72 int CMS_RecipientInfo_kari_get0_alg(CMS_RecipientInfo
*ri
,
74 ASN1_OCTET_STRING
**pukm
)
76 if (ri
->type
!= CMS_RECIPINFO_AGREE
) {
77 CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_ALG
,
78 CMS_R_NOT_KEY_AGREEMENT
);
82 *palg
= ri
->d
.kari
->keyEncryptionAlgorithm
;
84 *pukm
= ri
->d
.kari
->ukm
;
88 /* Retrieve recipient encrypted keys from a kari */
90 STACK_OF(CMS_RecipientEncryptedKey
)
91 *CMS_RecipientInfo_kari_get0_reks(CMS_RecipientInfo
*ri
)
93 if (ri
->type
!= CMS_RECIPINFO_AGREE
) {
94 CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_REKS
,
95 CMS_R_NOT_KEY_AGREEMENT
);
98 return ri
->d
.kari
->recipientEncryptedKeys
;
101 int CMS_RecipientInfo_kari_get0_orig_id(CMS_RecipientInfo
*ri
,
103 ASN1_BIT_STRING
**pubkey
,
104 ASN1_OCTET_STRING
**keyid
,
108 CMS_OriginatorIdentifierOrKey
*oik
;
109 if (ri
->type
!= CMS_RECIPINFO_AGREE
) {
110 CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_ORIG_ID
,
111 CMS_R_NOT_KEY_AGREEMENT
);
114 oik
= ri
->d
.kari
->originator
;
125 if (oik
->type
== CMS_OIK_ISSUER_SERIAL
) {
127 *issuer
= oik
->d
.issuerAndSerialNumber
->issuer
;
129 *sno
= oik
->d
.issuerAndSerialNumber
->serialNumber
;
130 } else if (oik
->type
== CMS_OIK_KEYIDENTIFIER
) {
132 *keyid
= oik
->d
.subjectKeyIdentifier
;
133 } else if (oik
->type
== CMS_OIK_PUBKEY
) {
135 *pubalg
= oik
->d
.originatorKey
->algorithm
;
137 *pubkey
= oik
->d
.originatorKey
->publicKey
;
143 int CMS_RecipientInfo_kari_orig_id_cmp(CMS_RecipientInfo
*ri
, X509
*cert
)
145 CMS_OriginatorIdentifierOrKey
*oik
;
146 if (ri
->type
!= CMS_RECIPINFO_AGREE
) {
147 CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_ORIG_ID_CMP
,
148 CMS_R_NOT_KEY_AGREEMENT
);
151 oik
= ri
->d
.kari
->originator
;
152 if (oik
->type
== CMS_OIK_ISSUER_SERIAL
)
153 return cms_ias_cert_cmp(oik
->d
.issuerAndSerialNumber
, cert
);
154 else if (oik
->type
== CMS_OIK_KEYIDENTIFIER
)
155 return cms_keyid_cert_cmp(oik
->d
.subjectKeyIdentifier
, cert
);
159 int CMS_RecipientEncryptedKey_get0_id(CMS_RecipientEncryptedKey
*rek
,
160 ASN1_OCTET_STRING
**keyid
,
161 ASN1_GENERALIZEDTIME
**tm
,
162 CMS_OtherKeyAttribute
**other
,
163 X509_NAME
**issuer
, ASN1_INTEGER
**sno
)
165 CMS_KeyAgreeRecipientIdentifier
*rid
= rek
->rid
;
166 if (rid
->type
== CMS_REK_ISSUER_SERIAL
) {
168 *issuer
= rid
->d
.issuerAndSerialNumber
->issuer
;
170 *sno
= rid
->d
.issuerAndSerialNumber
->serialNumber
;
177 } else if (rid
->type
== CMS_REK_KEYIDENTIFIER
) {
179 *keyid
= rid
->d
.rKeyId
->subjectKeyIdentifier
;
181 *tm
= rid
->d
.rKeyId
->date
;
183 *other
= rid
->d
.rKeyId
->other
;
193 int CMS_RecipientEncryptedKey_cert_cmp(CMS_RecipientEncryptedKey
*rek
,
196 CMS_KeyAgreeRecipientIdentifier
*rid
= rek
->rid
;
197 if (rid
->type
== CMS_REK_ISSUER_SERIAL
)
198 return cms_ias_cert_cmp(rid
->d
.issuerAndSerialNumber
, cert
);
199 else if (rid
->type
== CMS_REK_KEYIDENTIFIER
)
200 return cms_keyid_cert_cmp(rid
->d
.rKeyId
->subjectKeyIdentifier
, cert
);
205 int CMS_RecipientInfo_kari_set0_pkey(CMS_RecipientInfo
*ri
, EVP_PKEY
*pk
)
208 CMS_KeyAgreeRecipientInfo
*kari
= ri
->d
.kari
;
210 EVP_PKEY_CTX_free(kari
->pctx
);
215 pctx
= EVP_PKEY_CTX_new(pk
, NULL
);
216 if (!pctx
|| !EVP_PKEY_derive_init(pctx
))
222 EVP_PKEY_CTX_free(pctx
);
226 EVP_CIPHER_CTX
*CMS_RecipientInfo_kari_get0_ctx(CMS_RecipientInfo
*ri
)
228 if (ri
->type
== CMS_RECIPINFO_AGREE
)
229 return &ri
->d
.kari
->ctx
;
234 * Derive KEK and decrypt/encrypt with it to produce either the original CEK
235 * or the encrypted CEK.
238 static int cms_kek_cipher(unsigned char **pout
, size_t *poutlen
,
239 const unsigned char *in
, size_t inlen
,
240 CMS_KeyAgreeRecipientInfo
*kari
, int enc
)
242 /* Key encryption key */
243 unsigned char kek
[EVP_MAX_KEY_LENGTH
];
246 unsigned char *out
= NULL
;
248 keklen
= EVP_CIPHER_CTX_key_length(&kari
->ctx
);
249 if (keklen
> EVP_MAX_KEY_LENGTH
)
252 if (EVP_PKEY_derive(kari
->pctx
, kek
, &keklen
) <= 0)
254 /* Set KEK in context */
255 if (!EVP_CipherInit_ex(&kari
->ctx
, NULL
, NULL
, kek
, NULL
, enc
))
257 /* obtain output length of ciphered key */
258 if (!EVP_CipherUpdate(&kari
->ctx
, NULL
, &outlen
, in
, inlen
))
260 out
= OPENSSL_malloc(outlen
);
263 if (!EVP_CipherUpdate(&kari
->ctx
, out
, &outlen
, in
, inlen
))
266 *poutlen
= (size_t)outlen
;
270 OPENSSL_cleanse(kek
, keklen
);
273 EVP_CIPHER_CTX_cleanup(&kari
->ctx
);
274 EVP_PKEY_CTX_free(kari
->pctx
);
279 int CMS_RecipientInfo_kari_decrypt(CMS_ContentInfo
*cms
,
280 CMS_RecipientInfo
*ri
,
281 CMS_RecipientEncryptedKey
*rek
)
284 unsigned char *enckey
= NULL
, *cek
= NULL
;
287 CMS_EncryptedContentInfo
*ec
;
288 enckeylen
= rek
->encryptedKey
->length
;
289 enckey
= rek
->encryptedKey
->data
;
290 /* Setup all parameters to derive KEK */
291 if (!cms_env_asn1_ctrl(ri
, 1))
293 /* Attempt to decrypt CEK */
294 if (!cms_kek_cipher(&cek
, &ceklen
, enckey
, enckeylen
, ri
->d
.kari
, 0))
296 ec
= cms
->d
.envelopedData
->encryptedContentInfo
;
298 OPENSSL_cleanse(ec
->key
, ec
->keylen
);
299 OPENSSL_free(ec
->key
);
311 /* Create ephemeral key and initialise context based on it */
312 static int cms_kari_create_ephemeral_key(CMS_KeyAgreeRecipientInfo
*kari
,
315 EVP_PKEY_CTX
*pctx
= NULL
;
316 EVP_PKEY
*ekey
= NULL
;
318 pctx
= EVP_PKEY_CTX_new(pk
, NULL
);
321 if (EVP_PKEY_keygen_init(pctx
) <= 0)
323 if (EVP_PKEY_keygen(pctx
, &ekey
) <= 0)
325 EVP_PKEY_CTX_free(pctx
);
326 pctx
= EVP_PKEY_CTX_new(ekey
, NULL
);
329 if (EVP_PKEY_derive_init(pctx
) <= 0)
335 EVP_PKEY_CTX_free(pctx
);
341 /* Initialise a ktri based on passed certificate and key */
343 int cms_RecipientInfo_kari_init(CMS_RecipientInfo
*ri
, X509
*recip
,
344 EVP_PKEY
*pk
, unsigned int flags
)
346 CMS_KeyAgreeRecipientInfo
*kari
;
347 CMS_RecipientEncryptedKey
*rek
= NULL
;
349 ri
->d
.kari
= M_ASN1_new_of(CMS_KeyAgreeRecipientInfo
);
352 ri
->type
= CMS_RECIPINFO_AGREE
;
357 rek
= M_ASN1_new_of(CMS_RecipientEncryptedKey
);
358 if (!sk_CMS_RecipientEncryptedKey_push(kari
->recipientEncryptedKeys
, rek
)) {
359 M_ASN1_free_of(rek
, CMS_RecipientEncryptedKey
);
363 if (flags
& CMS_USE_KEYID
) {
364 rek
->rid
->type
= CMS_REK_KEYIDENTIFIER
;
365 if (!cms_set1_keyid(&rek
->rid
->d
.rKeyId
->subjectKeyIdentifier
, recip
))
368 rek
->rid
->type
= CMS_REK_ISSUER_SERIAL
;
369 if (!cms_set1_ias(&rek
->rid
->d
.issuerAndSerialNumber
, recip
))
373 /* Create ephemeral key */
374 if (!cms_kari_create_ephemeral_key(kari
, pk
))
377 CRYPTO_add(&pk
->references
, 1, CRYPTO_LOCK_EVP_PKEY
);
382 static int cms_wrap_init(CMS_KeyAgreeRecipientInfo
*kari
,
383 const EVP_CIPHER
*cipher
)
385 EVP_CIPHER_CTX
*ctx
= &kari
->ctx
;
386 const EVP_CIPHER
*kekcipher
;
387 int keylen
= EVP_CIPHER_key_length(cipher
);
388 /* If a suitable wrap algorithm is already set nothing to do */
389 kekcipher
= EVP_CIPHER_CTX_cipher(ctx
);
392 if (EVP_CIPHER_CTX_mode(ctx
) != EVP_CIPH_WRAP_MODE
)
397 * Pick a cipher based on content encryption cipher. If it is DES3 use
398 * DES3 wrap otherwise use AES wrap similar to key size.
400 if (EVP_CIPHER_type(cipher
) == NID_des_ede3_cbc
)
401 kekcipher
= EVP_des_ede3_wrap();
402 else if (keylen
<= 16)
403 kekcipher
= EVP_aes_128_wrap();
404 else if (keylen
<= 24)
405 kekcipher
= EVP_aes_192_wrap();
407 kekcipher
= EVP_aes_256_wrap();
408 return EVP_EncryptInit_ex(ctx
, kekcipher
, NULL
, NULL
, NULL
);
411 /* Encrypt content key in key agreement recipient info */
413 int cms_RecipientInfo_kari_encrypt(CMS_ContentInfo
*cms
,
414 CMS_RecipientInfo
*ri
)
416 CMS_KeyAgreeRecipientInfo
*kari
;
417 CMS_EncryptedContentInfo
*ec
;
418 CMS_RecipientEncryptedKey
*rek
;
419 STACK_OF(CMS_RecipientEncryptedKey
) *reks
;
422 if (ri
->type
!= CMS_RECIPINFO_AGREE
) {
423 CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_ENCRYPT
, CMS_R_NOT_KEY_AGREEMENT
);
427 reks
= kari
->recipientEncryptedKeys
;
428 ec
= cms
->d
.envelopedData
->encryptedContentInfo
;
429 /* Initialise wrap algorithm parameters */
430 if (!cms_wrap_init(kari
, ec
->cipher
))
433 * If no orignator key set up initialise for ephemeral key the public key
434 * ASN1 structure will set the actual public key value.
436 if (kari
->originator
->type
== -1) {
437 CMS_OriginatorIdentifierOrKey
*oik
= kari
->originator
;
438 oik
->type
= CMS_OIK_PUBKEY
;
439 oik
->d
.originatorKey
= M_ASN1_new_of(CMS_OriginatorPublicKey
);
440 if (!oik
->d
.originatorKey
)
443 /* Initialise KDF algorithm */
444 if (!cms_env_asn1_ctrl(ri
, 0))
446 /* For each rek, derive KEK, encrypt CEK */
447 for (i
= 0; i
< sk_CMS_RecipientEncryptedKey_num(reks
); i
++) {
448 unsigned char *enckey
;
450 rek
= sk_CMS_RecipientEncryptedKey_value(reks
, i
);
451 if (EVP_PKEY_derive_set_peer(kari
->pctx
, rek
->pkey
) <= 0)
453 if (!cms_kek_cipher(&enckey
, &enckeylen
, ec
->key
, ec
->keylen
,
456 ASN1_STRING_set0(rek
->encryptedKey
, enckey
, enckeylen
);