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))
221 EVP_PKEY_CTX_free(pctx);
225 EVP_CIPHER_CTX *CMS_RecipientInfo_kari_get0_ctx(CMS_RecipientInfo *ri)
227 if (ri->type == CMS_RECIPINFO_AGREE)
228 return &ri->d.kari->ctx;
233 * Derive KEK and decrypt/encrypt with it to produce either the original CEK
234 * or the encrypted CEK.
237 static int cms_kek_cipher(unsigned char **pout, size_t *poutlen,
238 const unsigned char *in, size_t inlen,
239 CMS_KeyAgreeRecipientInfo *kari, int enc)
241 /* Key encryption key */
242 unsigned char kek[EVP_MAX_KEY_LENGTH];
245 unsigned char *out = NULL;
247 keklen = EVP_CIPHER_CTX_key_length(&kari->ctx);
248 if (keklen > EVP_MAX_KEY_LENGTH)
251 if (EVP_PKEY_derive(kari->pctx, kek, &keklen) <= 0)
253 /* Set KEK in context */
254 if (!EVP_CipherInit_ex(&kari->ctx, NULL, NULL, kek, NULL, enc))
256 /* obtain output length of ciphered key */
257 if (!EVP_CipherUpdate(&kari->ctx, NULL, &outlen, in, inlen))
259 out = OPENSSL_malloc(outlen);
262 if (!EVP_CipherUpdate(&kari->ctx, out, &outlen, in, inlen))
265 *poutlen = (size_t)outlen;
269 OPENSSL_cleanse(kek, keklen);
272 EVP_CIPHER_CTX_cleanup(&kari->ctx);
273 EVP_PKEY_CTX_free(kari->pctx);
278 int CMS_RecipientInfo_kari_decrypt(CMS_ContentInfo *cms,
279 CMS_RecipientInfo *ri,
280 CMS_RecipientEncryptedKey *rek)
283 unsigned char *enckey = NULL, *cek = NULL;
286 CMS_EncryptedContentInfo *ec;
287 enckeylen = rek->encryptedKey->length;
288 enckey = rek->encryptedKey->data;
289 /* Setup all parameters to derive KEK */
290 if (!cms_env_asn1_ctrl(ri, 1))
292 /* Attempt to decrypt CEK */
293 if (!cms_kek_cipher(&cek, &ceklen, enckey, enckeylen, ri->d.kari, 0))
295 ec = cms->d.envelopedData->encryptedContentInfo;
297 OPENSSL_cleanse(ec->key, ec->keylen);
298 OPENSSL_free(ec->key);
310 /* Create ephemeral key and initialise context based on it */
311 static int cms_kari_create_ephemeral_key(CMS_KeyAgreeRecipientInfo *kari,
314 EVP_PKEY_CTX *pctx = NULL;
315 EVP_PKEY *ekey = NULL;
317 pctx = EVP_PKEY_CTX_new(pk, NULL);
320 if (EVP_PKEY_keygen_init(pctx) <= 0)
322 if (EVP_PKEY_keygen(pctx, &ekey) <= 0)
324 EVP_PKEY_CTX_free(pctx);
325 pctx = EVP_PKEY_CTX_new(ekey, NULL);
328 if (EVP_PKEY_derive_init(pctx) <= 0)
334 EVP_PKEY_CTX_free(pctx);
339 /* Initialise a ktri based on passed certificate and key */
341 int cms_RecipientInfo_kari_init(CMS_RecipientInfo *ri, X509 *recip,
342 EVP_PKEY *pk, unsigned int flags)
344 CMS_KeyAgreeRecipientInfo *kari;
345 CMS_RecipientEncryptedKey *rek = NULL;
347 ri->d.kari = M_ASN1_new_of(CMS_KeyAgreeRecipientInfo);
350 ri->type = CMS_RECIPINFO_AGREE;
355 rek = M_ASN1_new_of(CMS_RecipientEncryptedKey);
356 if (!sk_CMS_RecipientEncryptedKey_push(kari->recipientEncryptedKeys, rek)) {
357 M_ASN1_free_of(rek, CMS_RecipientEncryptedKey);
361 if (flags & CMS_USE_KEYID) {
362 rek->rid->type = CMS_REK_KEYIDENTIFIER;
363 if (!cms_set1_keyid(&rek->rid->d.rKeyId->subjectKeyIdentifier, recip))
366 rek->rid->type = CMS_REK_ISSUER_SERIAL;
367 if (!cms_set1_ias(&rek->rid->d.issuerAndSerialNumber, recip))
371 /* Create ephemeral key */
372 if (!cms_kari_create_ephemeral_key(kari, pk))
375 CRYPTO_add(&pk->references, 1, CRYPTO_LOCK_EVP_PKEY);
380 static int cms_wrap_init(CMS_KeyAgreeRecipientInfo *kari,
381 const EVP_CIPHER *cipher)
383 EVP_CIPHER_CTX *ctx = &kari->ctx;
384 const EVP_CIPHER *kekcipher;
385 int keylen = EVP_CIPHER_key_length(cipher);
386 /* If a suitable wrap algorithm is already set nothing to do */
387 kekcipher = EVP_CIPHER_CTX_cipher(ctx);
390 if (EVP_CIPHER_CTX_mode(ctx) != EVP_CIPH_WRAP_MODE)
395 * Pick a cipher based on content encryption cipher. If it is DES3 use
396 * DES3 wrap otherwise use AES wrap similar to key size.
398 if (EVP_CIPHER_type(cipher) == NID_des_ede3_cbc)
399 kekcipher = EVP_des_ede3_wrap();
400 else if (keylen <= 16)
401 kekcipher = EVP_aes_128_wrap();
402 else if (keylen <= 24)
403 kekcipher = EVP_aes_192_wrap();
405 kekcipher = EVP_aes_256_wrap();
406 return EVP_EncryptInit_ex(ctx, kekcipher, NULL, NULL, NULL);
409 /* Encrypt content key in key agreement recipient info */
411 int cms_RecipientInfo_kari_encrypt(CMS_ContentInfo *cms,
412 CMS_RecipientInfo *ri)
414 CMS_KeyAgreeRecipientInfo *kari;
415 CMS_EncryptedContentInfo *ec;
416 CMS_RecipientEncryptedKey *rek;
417 STACK_OF(CMS_RecipientEncryptedKey) *reks;
420 if (ri->type != CMS_RECIPINFO_AGREE) {
421 CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_ENCRYPT, CMS_R_NOT_KEY_AGREEMENT);
425 reks = kari->recipientEncryptedKeys;
426 ec = cms->d.envelopedData->encryptedContentInfo;
427 /* Initialise wrap algorithm parameters */
428 if (!cms_wrap_init(kari, ec->cipher))
431 * If no orignator key set up initialise for ephemeral key the public key
432 * ASN1 structure will set the actual public key value.
434 if (kari->originator->type == -1) {
435 CMS_OriginatorIdentifierOrKey *oik = kari->originator;
436 oik->type = CMS_OIK_PUBKEY;
437 oik->d.originatorKey = M_ASN1_new_of(CMS_OriginatorPublicKey);
438 if (!oik->d.originatorKey)
441 /* Initialise KDF algorithm */
442 if (!cms_env_asn1_ctrl(ri, 0))
444 /* For each rek, derive KEK, encrypt CEK */
445 for (i = 0; i < sk_CMS_RecipientEncryptedKey_num(reks); i++) {
446 unsigned char *enckey;
448 rek = sk_CMS_RecipientEncryptedKey_value(reks, i);
449 if (EVP_PKEY_derive_set_peer(kari->pctx, rek->pkey) <= 0)
451 if (!cms_kek_cipher(&enckey, &enckeylen, ec->key, ec->keylen,
454 ASN1_STRING_set0(rek->encryptedKey, enckey, enckeylen);