Line data Source code
1 : /* crypto/cms/cms_kari.c */
2 : /*
3 : * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
4 : * project.
5 : */
6 : /* ====================================================================
7 : * Copyright (c) 2013 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 <openssl/aes.h>
63 : #include "cms_lcl.h"
64 : #include "asn1_locl.h"
65 :
66 : DECLARE_ASN1_ITEM(CMS_KeyAgreeRecipientInfo)
67 : DECLARE_ASN1_ITEM(CMS_RecipientEncryptedKey)
68 : DECLARE_ASN1_ITEM(CMS_OriginatorPublicKey)
69 : DECLARE_ASN1_ITEM(CMS_RecipientKeyIdentifier)
70 :
71 : /* Key Agreement Recipient Info (KARI) routines */
72 :
73 0 : int CMS_RecipientInfo_kari_get0_alg(CMS_RecipientInfo *ri,
74 : X509_ALGOR **palg,
75 : ASN1_OCTET_STRING **pukm)
76 : {
77 0 : if (ri->type != CMS_RECIPINFO_AGREE) {
78 0 : CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_ALG,
79 : CMS_R_NOT_KEY_AGREEMENT);
80 0 : return 0;
81 : }
82 0 : if (palg)
83 0 : *palg = ri->d.kari->keyEncryptionAlgorithm;
84 0 : if (pukm)
85 0 : *pukm = ri->d.kari->ukm;
86 : return 1;
87 : }
88 :
89 : /* Retrieve recipient encrypted keys from a kari */
90 :
91 : STACK_OF(CMS_RecipientEncryptedKey)
92 0 : *CMS_RecipientInfo_kari_get0_reks(CMS_RecipientInfo *ri)
93 : {
94 0 : if (ri->type != CMS_RECIPINFO_AGREE) {
95 0 : CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_REKS,
96 : CMS_R_NOT_KEY_AGREEMENT);
97 0 : return NULL;
98 : }
99 0 : return ri->d.kari->recipientEncryptedKeys;
100 : }
101 :
102 0 : int CMS_RecipientInfo_kari_get0_orig_id(CMS_RecipientInfo *ri,
103 : X509_ALGOR **pubalg,
104 : ASN1_BIT_STRING **pubkey,
105 : ASN1_OCTET_STRING **keyid,
106 : X509_NAME **issuer,
107 : ASN1_INTEGER **sno)
108 : {
109 : CMS_OriginatorIdentifierOrKey *oik;
110 0 : if (ri->type != CMS_RECIPINFO_AGREE) {
111 0 : CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_ORIG_ID,
112 : CMS_R_NOT_KEY_AGREEMENT);
113 0 : return 0;
114 : }
115 0 : oik = ri->d.kari->originator;
116 0 : if (issuer)
117 0 : *issuer = NULL;
118 0 : if (sno)
119 0 : *sno = NULL;
120 0 : if (keyid)
121 0 : *keyid = NULL;
122 0 : if (pubalg)
123 0 : *pubalg = NULL;
124 0 : if (pubkey)
125 0 : *pubkey = NULL;
126 0 : if (oik->type == CMS_OIK_ISSUER_SERIAL) {
127 0 : if (issuer)
128 0 : *issuer = oik->d.issuerAndSerialNumber->issuer;
129 0 : if (sno)
130 0 : *sno = oik->d.issuerAndSerialNumber->serialNumber;
131 0 : } else if (oik->type == CMS_OIK_KEYIDENTIFIER) {
132 0 : if (keyid)
133 0 : *keyid = oik->d.subjectKeyIdentifier;
134 0 : } else if (oik->type == CMS_OIK_PUBKEY) {
135 0 : if (pubalg)
136 0 : *pubalg = oik->d.originatorKey->algorithm;
137 0 : if (pubkey)
138 0 : *pubkey = oik->d.originatorKey->publicKey;
139 : } else
140 : return 0;
141 : return 1;
142 : }
143 :
144 0 : int CMS_RecipientInfo_kari_orig_id_cmp(CMS_RecipientInfo *ri, X509 *cert)
145 : {
146 : CMS_OriginatorIdentifierOrKey *oik;
147 0 : if (ri->type != CMS_RECIPINFO_AGREE) {
148 0 : CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_ORIG_ID_CMP,
149 : CMS_R_NOT_KEY_AGREEMENT);
150 0 : return -2;
151 : }
152 0 : oik = ri->d.kari->originator;
153 0 : if (oik->type == CMS_OIK_ISSUER_SERIAL)
154 0 : return cms_ias_cert_cmp(oik->d.issuerAndSerialNumber, cert);
155 0 : else if (oik->type == CMS_OIK_KEYIDENTIFIER)
156 0 : return cms_keyid_cert_cmp(oik->d.subjectKeyIdentifier, cert);
157 : return -1;
158 : }
159 :
160 0 : int CMS_RecipientEncryptedKey_get0_id(CMS_RecipientEncryptedKey *rek,
161 : ASN1_OCTET_STRING **keyid,
162 : ASN1_GENERALIZEDTIME **tm,
163 : CMS_OtherKeyAttribute **other,
164 : X509_NAME **issuer, ASN1_INTEGER **sno)
165 : {
166 0 : CMS_KeyAgreeRecipientIdentifier *rid = rek->rid;
167 0 : if (rid->type == CMS_REK_ISSUER_SERIAL) {
168 0 : if (issuer)
169 0 : *issuer = rid->d.issuerAndSerialNumber->issuer;
170 0 : if (sno)
171 0 : *sno = rid->d.issuerAndSerialNumber->serialNumber;
172 0 : if (keyid)
173 0 : *keyid = NULL;
174 0 : if (tm)
175 0 : *tm = NULL;
176 0 : if (other)
177 0 : *other = NULL;
178 0 : } else if (rid->type == CMS_REK_KEYIDENTIFIER) {
179 0 : if (keyid)
180 0 : *keyid = rid->d.rKeyId->subjectKeyIdentifier;
181 0 : if (tm)
182 0 : *tm = rid->d.rKeyId->date;
183 0 : if (other)
184 0 : *other = rid->d.rKeyId->other;
185 0 : if (issuer)
186 0 : *issuer = NULL;
187 0 : if (sno)
188 0 : *sno = NULL;
189 : } else
190 : return 0;
191 : return 1;
192 : }
193 :
194 0 : int CMS_RecipientEncryptedKey_cert_cmp(CMS_RecipientEncryptedKey *rek,
195 : X509 *cert)
196 : {
197 0 : CMS_KeyAgreeRecipientIdentifier *rid = rek->rid;
198 0 : if (rid->type == CMS_REK_ISSUER_SERIAL)
199 0 : return cms_ias_cert_cmp(rid->d.issuerAndSerialNumber, cert);
200 0 : else if (rid->type == CMS_REK_KEYIDENTIFIER)
201 0 : return cms_keyid_cert_cmp(rid->d.rKeyId->subjectKeyIdentifier, cert);
202 : else
203 : return -1;
204 : }
205 :
206 0 : int CMS_RecipientInfo_kari_set0_pkey(CMS_RecipientInfo *ri, EVP_PKEY *pk)
207 : {
208 : EVP_PKEY_CTX *pctx;
209 0 : CMS_KeyAgreeRecipientInfo *kari = ri->d.kari;
210 0 : if (kari->pctx) {
211 0 : EVP_PKEY_CTX_free(kari->pctx);
212 0 : kari->pctx = NULL;
213 : }
214 0 : if (!pk)
215 : return 1;
216 0 : pctx = EVP_PKEY_CTX_new(pk, NULL);
217 0 : if (!pctx || !EVP_PKEY_derive_init(pctx))
218 : goto err;
219 0 : kari->pctx = pctx;
220 0 : return 1;
221 : err:
222 0 : if (pctx)
223 0 : EVP_PKEY_CTX_free(pctx);
224 : return 0;
225 : }
226 :
227 0 : EVP_CIPHER_CTX *CMS_RecipientInfo_kari_get0_ctx(CMS_RecipientInfo *ri)
228 : {
229 0 : if (ri->type == CMS_RECIPINFO_AGREE)
230 0 : return &ri->d.kari->ctx;
231 : return NULL;
232 : }
233 :
234 : /*
235 : * Derive KEK and decrypt/encrypt with it to produce either the original CEK
236 : * or the encrypted CEK.
237 : */
238 :
239 0 : static int cms_kek_cipher(unsigned char **pout, size_t *poutlen,
240 : const unsigned char *in, size_t inlen,
241 : CMS_KeyAgreeRecipientInfo *kari, int enc)
242 : {
243 : /* Key encryption key */
244 : unsigned char kek[EVP_MAX_KEY_LENGTH];
245 : size_t keklen;
246 : int rv = 0;
247 : unsigned char *out = NULL;
248 : int outlen;
249 0 : keklen = EVP_CIPHER_CTX_key_length(&kari->ctx);
250 0 : if (keklen > EVP_MAX_KEY_LENGTH)
251 : return 0;
252 : /* Derive KEK */
253 0 : if (EVP_PKEY_derive(kari->pctx, kek, &keklen) <= 0)
254 : goto err;
255 : /* Set KEK in context */
256 0 : if (!EVP_CipherInit_ex(&kari->ctx, NULL, NULL, kek, NULL, enc))
257 : goto err;
258 : /* obtain output length of ciphered key */
259 0 : if (!EVP_CipherUpdate(&kari->ctx, NULL, &outlen, in, inlen))
260 : goto err;
261 0 : out = OPENSSL_malloc(outlen);
262 0 : if (!out)
263 : goto err;
264 0 : if (!EVP_CipherUpdate(&kari->ctx, out, &outlen, in, inlen))
265 : goto err;
266 0 : *pout = out;
267 0 : *poutlen = (size_t)outlen;
268 : rv = 1;
269 :
270 : err:
271 0 : OPENSSL_cleanse(kek, keklen);
272 0 : if (!rv && out)
273 0 : OPENSSL_free(out);
274 0 : EVP_CIPHER_CTX_cleanup(&kari->ctx);
275 0 : EVP_PKEY_CTX_free(kari->pctx);
276 0 : kari->pctx = NULL;
277 0 : return rv;
278 : }
279 :
280 0 : int CMS_RecipientInfo_kari_decrypt(CMS_ContentInfo *cms,
281 : CMS_RecipientInfo *ri,
282 : CMS_RecipientEncryptedKey *rek)
283 : {
284 : int rv = 0;
285 0 : unsigned char *enckey = NULL, *cek = NULL;
286 : size_t enckeylen;
287 : size_t ceklen;
288 : CMS_EncryptedContentInfo *ec;
289 0 : enckeylen = rek->encryptedKey->length;
290 0 : enckey = rek->encryptedKey->data;
291 : /* Setup all parameters to derive KEK */
292 0 : if (!cms_env_asn1_ctrl(ri, 1))
293 : goto err;
294 : /* Attempt to decrypt CEK */
295 0 : if (!cms_kek_cipher(&cek, &ceklen, enckey, enckeylen, ri->d.kari, 0))
296 : goto err;
297 0 : ec = cms->d.envelopedData->encryptedContentInfo;
298 0 : if (ec->key) {
299 0 : OPENSSL_cleanse(ec->key, ec->keylen);
300 0 : OPENSSL_free(ec->key);
301 : }
302 0 : ec->key = cek;
303 0 : ec->keylen = ceklen;
304 0 : cek = NULL;
305 : rv = 1;
306 : err:
307 0 : if (cek)
308 0 : OPENSSL_free(cek);
309 0 : return rv;
310 : }
311 :
312 : /* Create ephemeral key and initialise context based on it */
313 0 : static int cms_kari_create_ephemeral_key(CMS_KeyAgreeRecipientInfo *kari,
314 : EVP_PKEY *pk)
315 : {
316 : EVP_PKEY_CTX *pctx = NULL;
317 0 : EVP_PKEY *ekey = NULL;
318 : int rv = 0;
319 0 : pctx = EVP_PKEY_CTX_new(pk, NULL);
320 0 : if (!pctx)
321 : goto err;
322 0 : if (EVP_PKEY_keygen_init(pctx) <= 0)
323 : goto err;
324 0 : if (EVP_PKEY_keygen(pctx, &ekey) <= 0)
325 : goto err;
326 0 : EVP_PKEY_CTX_free(pctx);
327 0 : pctx = EVP_PKEY_CTX_new(ekey, NULL);
328 0 : if (!pctx)
329 : goto err;
330 0 : if (EVP_PKEY_derive_init(pctx) <= 0)
331 : goto err;
332 0 : kari->pctx = pctx;
333 : rv = 1;
334 : err:
335 0 : if (!rv && pctx)
336 0 : EVP_PKEY_CTX_free(pctx);
337 0 : if (ekey)
338 0 : EVP_PKEY_free(ekey);
339 0 : return rv;
340 : }
341 :
342 : /* Initialise a ktri based on passed certificate and key */
343 :
344 0 : int cms_RecipientInfo_kari_init(CMS_RecipientInfo *ri, X509 *recip,
345 : EVP_PKEY *pk, unsigned int flags)
346 : {
347 : CMS_KeyAgreeRecipientInfo *kari;
348 : CMS_RecipientEncryptedKey *rek = NULL;
349 :
350 0 : ri->d.kari = M_ASN1_new_of(CMS_KeyAgreeRecipientInfo);
351 0 : if (!ri->d.kari)
352 : return 0;
353 0 : ri->type = CMS_RECIPINFO_AGREE;
354 :
355 : kari = ri->d.kari;
356 0 : kari->version = 3;
357 :
358 0 : rek = M_ASN1_new_of(CMS_RecipientEncryptedKey);
359 0 : if (!sk_CMS_RecipientEncryptedKey_push(kari->recipientEncryptedKeys, rek)) {
360 0 : M_ASN1_free_of(rek, CMS_RecipientEncryptedKey);
361 0 : return 0;
362 : }
363 :
364 0 : if (flags & CMS_USE_KEYID) {
365 0 : rek->rid->type = CMS_REK_KEYIDENTIFIER;
366 0 : rek->rid->d.rKeyId = M_ASN1_new_of(CMS_RecipientKeyIdentifier);
367 0 : if (rek->rid->d.rKeyId == NULL)
368 : return 0;
369 0 : if (!cms_set1_keyid(&rek->rid->d.rKeyId->subjectKeyIdentifier, recip))
370 : return 0;
371 : } else {
372 0 : rek->rid->type = CMS_REK_ISSUER_SERIAL;
373 0 : if (!cms_set1_ias(&rek->rid->d.issuerAndSerialNumber, recip))
374 : return 0;
375 : }
376 :
377 : /* Create ephemeral key */
378 0 : if (!cms_kari_create_ephemeral_key(kari, pk))
379 : return 0;
380 :
381 0 : CRYPTO_add(&pk->references, 1, CRYPTO_LOCK_EVP_PKEY);
382 0 : rek->pkey = pk;
383 0 : return 1;
384 : }
385 :
386 0 : static int cms_wrap_init(CMS_KeyAgreeRecipientInfo *kari,
387 : const EVP_CIPHER *cipher)
388 : {
389 0 : EVP_CIPHER_CTX *ctx = &kari->ctx;
390 : const EVP_CIPHER *kekcipher;
391 0 : int keylen = EVP_CIPHER_key_length(cipher);
392 : /* If a suitable wrap algorithm is already set nothing to do */
393 0 : kekcipher = EVP_CIPHER_CTX_cipher(ctx);
394 :
395 0 : if (kekcipher) {
396 0 : if (EVP_CIPHER_CTX_mode(ctx) != EVP_CIPH_WRAP_MODE)
397 : return 0;
398 0 : return 1;
399 : }
400 : /*
401 : * Pick a cipher based on content encryption cipher. If it is DES3 use
402 : * DES3 wrap otherwise use AES wrap similar to key size.
403 : */
404 0 : if (EVP_CIPHER_type(cipher) == NID_des_ede3_cbc)
405 0 : kekcipher = EVP_des_ede3_wrap();
406 0 : else if (keylen <= 16)
407 0 : kekcipher = EVP_aes_128_wrap();
408 0 : else if (keylen <= 24)
409 0 : kekcipher = EVP_aes_192_wrap();
410 : else
411 0 : kekcipher = EVP_aes_256_wrap();
412 0 : return EVP_EncryptInit_ex(ctx, kekcipher, NULL, NULL, NULL);
413 : }
414 :
415 : /* Encrypt content key in key agreement recipient info */
416 :
417 0 : int cms_RecipientInfo_kari_encrypt(CMS_ContentInfo *cms,
418 : CMS_RecipientInfo *ri)
419 : {
420 : CMS_KeyAgreeRecipientInfo *kari;
421 : CMS_EncryptedContentInfo *ec;
422 : CMS_RecipientEncryptedKey *rek;
423 : STACK_OF(CMS_RecipientEncryptedKey) *reks;
424 : int i;
425 :
426 0 : if (ri->type != CMS_RECIPINFO_AGREE) {
427 0 : CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_ENCRYPT, CMS_R_NOT_KEY_AGREEMENT);
428 0 : return 0;
429 : }
430 0 : kari = ri->d.kari;
431 0 : reks = kari->recipientEncryptedKeys;
432 0 : ec = cms->d.envelopedData->encryptedContentInfo;
433 : /* Initialise wrap algorithm parameters */
434 0 : if (!cms_wrap_init(kari, ec->cipher))
435 : return 0;
436 : /*
437 : * If no orignator key set up initialise for ephemeral key the public key
438 : * ASN1 structure will set the actual public key value.
439 : */
440 0 : if (kari->originator->type == -1) {
441 : CMS_OriginatorIdentifierOrKey *oik = kari->originator;
442 0 : oik->type = CMS_OIK_PUBKEY;
443 0 : oik->d.originatorKey = M_ASN1_new_of(CMS_OriginatorPublicKey);
444 0 : if (!oik->d.originatorKey)
445 : return 0;
446 : }
447 : /* Initialise KDF algorithm */
448 0 : if (!cms_env_asn1_ctrl(ri, 0))
449 : return 0;
450 : /* For each rek, derive KEK, encrypt CEK */
451 0 : for (i = 0; i < sk_CMS_RecipientEncryptedKey_num(reks); i++) {
452 : unsigned char *enckey;
453 : size_t enckeylen;
454 0 : rek = sk_CMS_RecipientEncryptedKey_value(reks, i);
455 0 : if (EVP_PKEY_derive_set_peer(kari->pctx, rek->pkey) <= 0)
456 0 : return 0;
457 0 : if (!cms_kek_cipher(&enckey, &enckeylen, ec->key, ec->keylen,
458 : kari, 1))
459 : return 0;
460 0 : ASN1_STRING_set0(rek->encryptedKey, enckey, enckeylen);
461 : }
462 :
463 : return 1;
464 :
465 : }
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