1/* crypto/cms/cms_pwri.c */
2/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3 * project.
4 */
5/* ====================================================================
6 * Copyright (c) 2009 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 <openssl/aes.h>
62#include "cms_lcl.h"
63#include "asn1_locl.h"
64
65int CMS_RecipientInfo_set0_password(CMS_RecipientInfo *ri,
66				unsigned char *pass, ossl_ssize_t passlen)
67	{
68	CMS_PasswordRecipientInfo *pwri;
69	if (ri->type != CMS_RECIPINFO_PASS)
70		{
71		CMSerr(CMS_F_CMS_RECIPIENTINFO_SET0_PASSWORD, CMS_R_NOT_PWRI);
72		return 0;
73		}
74
75	pwri = ri->d.pwri;
76	pwri->pass = pass;
77	if (pass && passlen < 0)
78		passlen = strlen((char *)pass);
79	pwri->passlen = passlen;
80	return 1;
81	}
82
83CMS_RecipientInfo *CMS_add0_recipient_password(CMS_ContentInfo *cms,
84					int iter, int wrap_nid, int pbe_nid,
85					unsigned char *pass,
86					ossl_ssize_t passlen,
87					const EVP_CIPHER *kekciph)
88	{
89	CMS_RecipientInfo *ri = NULL;
90	CMS_EnvelopedData *env;
91	CMS_PasswordRecipientInfo *pwri;
92	EVP_CIPHER_CTX ctx;
93	X509_ALGOR *encalg = NULL;
94	unsigned char iv[EVP_MAX_IV_LENGTH];
95	int ivlen;
96	env = cms_get0_enveloped(cms);
97	if (!env)
98		goto err;
99
100	if (wrap_nid <= 0)
101		wrap_nid = NID_id_alg_PWRI_KEK;
102
103	if (pbe_nid <= 0)
104		pbe_nid = NID_id_pbkdf2;
105
106	/* Get from enveloped data */
107	if (kekciph == NULL)
108		kekciph = env->encryptedContentInfo->cipher;
109
110	if (kekciph == NULL)
111		{
112		CMSerr(CMS_F_CMS_ADD0_RECIPIENT_PASSWORD, CMS_R_NO_CIPHER);
113		return NULL;
114		}
115	if (wrap_nid != NID_id_alg_PWRI_KEK)
116		{
117		CMSerr(CMS_F_CMS_ADD0_RECIPIENT_PASSWORD,
118				CMS_R_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM);
119		return NULL;
120		}
121
122	/* Setup algorithm identifier for cipher */
123	encalg = X509_ALGOR_new();
124	EVP_CIPHER_CTX_init(&ctx);
125
126	if (EVP_EncryptInit_ex(&ctx, kekciph, NULL, NULL, NULL) <= 0)
127		{
128		CMSerr(CMS_F_CMS_ADD0_RECIPIENT_PASSWORD, ERR_R_EVP_LIB);
129		goto err;
130		}
131
132	ivlen = EVP_CIPHER_CTX_iv_length(&ctx);
133
134	if (ivlen > 0)
135		{
136		if (RAND_pseudo_bytes(iv, ivlen) <= 0)
137			goto err;
138		if (EVP_EncryptInit_ex(&ctx, NULL, NULL, NULL, iv) <= 0)
139			{
140			CMSerr(CMS_F_CMS_ADD0_RECIPIENT_PASSWORD,
141							ERR_R_EVP_LIB);
142			goto err;
143			}
144		encalg->parameter = ASN1_TYPE_new();
145		if (!encalg->parameter)
146			{
147			CMSerr(CMS_F_CMS_ADD0_RECIPIENT_PASSWORD,
148							ERR_R_MALLOC_FAILURE);
149			goto err;
150			}
151		if (EVP_CIPHER_param_to_asn1(&ctx, encalg->parameter) <= 0)
152			{
153			CMSerr(CMS_F_CMS_ADD0_RECIPIENT_PASSWORD,
154				CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
155			goto err;
156			}
157		}
158
159
160	encalg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_type(&ctx));
161
162	EVP_CIPHER_CTX_cleanup(&ctx);
163
164	/* Initialize recipient info */
165	ri = M_ASN1_new_of(CMS_RecipientInfo);
166	if (!ri)
167		goto merr;
168
169	ri->d.pwri = M_ASN1_new_of(CMS_PasswordRecipientInfo);
170	if (!ri->d.pwri)
171		goto merr;
172	ri->type = CMS_RECIPINFO_PASS;
173
174	pwri = ri->d.pwri;
175	/* Since this is overwritten, free up empty structure already there */
176	X509_ALGOR_free(pwri->keyEncryptionAlgorithm);
177	pwri->keyEncryptionAlgorithm = X509_ALGOR_new();
178	if (!pwri->keyEncryptionAlgorithm)
179		goto merr;
180	pwri->keyEncryptionAlgorithm->algorithm = OBJ_nid2obj(wrap_nid);
181	pwri->keyEncryptionAlgorithm->parameter = ASN1_TYPE_new();
182	if (!pwri->keyEncryptionAlgorithm->parameter)
183		goto merr;
184
185        if(!ASN1_item_pack(encalg, ASN1_ITEM_rptr(X509_ALGOR),
186	    &pwri->keyEncryptionAlgorithm->parameter->value.sequence))
187		goto merr;
188        pwri->keyEncryptionAlgorithm->parameter->type = V_ASN1_SEQUENCE;
189
190	X509_ALGOR_free(encalg);
191	encalg = NULL;
192
193	/* Setup PBE algorithm */
194
195	pwri->keyDerivationAlgorithm = PKCS5_pbkdf2_set(iter, NULL, 0, -1, -1);
196
197	if (!pwri->keyDerivationAlgorithm)
198		goto err;
199
200	CMS_RecipientInfo_set0_password(ri, pass, passlen);
201	pwri->version = 0;
202
203	if (!sk_CMS_RecipientInfo_push(env->recipientInfos, ri))
204		goto merr;
205
206	return ri;
207
208	merr:
209	CMSerr(CMS_F_CMS_ADD0_RECIPIENT_PASSWORD, ERR_R_MALLOC_FAILURE);
210	err:
211	EVP_CIPHER_CTX_cleanup(&ctx);
212	if (ri)
213		M_ASN1_free_of(ri, CMS_RecipientInfo);
214	if (encalg)
215		X509_ALGOR_free(encalg);
216	return NULL;
217
218	}
219
220/* This is an implementation of the key wrapping mechanism in RFC3211,
221 * at some point this should go into EVP.
222 */
223
224static int kek_unwrap_key(unsigned char *out, size_t *outlen,
225		const unsigned char *in, size_t inlen, EVP_CIPHER_CTX *ctx)
226	{
227	size_t blocklen = EVP_CIPHER_CTX_block_size(ctx);
228	unsigned char *tmp;
229	int outl, rv = 0;
230	if (inlen < 2 * blocklen)
231		{
232		/* too small */
233		return 0;
234		}
235	if (inlen % blocklen)
236		{
237		/* Invalid size */
238		return 0;
239		}
240	tmp = OPENSSL_malloc(inlen);
241	/* setup IV by decrypting last two blocks */
242	EVP_DecryptUpdate(ctx, tmp + inlen - 2 * blocklen, &outl,
243				in  + inlen - 2 * blocklen, blocklen * 2);
244	/* Do a decrypt of last decrypted block to set IV to correct value
245	 * output it to start of buffer so we don't corrupt decrypted block
246	 * this works because buffer is at least two block lengths long.
247	 */
248	EVP_DecryptUpdate(ctx, tmp, &outl,
249				tmp  + inlen - blocklen, blocklen);
250	/* Can now decrypt first n - 1 blocks */
251	EVP_DecryptUpdate(ctx, tmp, &outl, in, inlen - blocklen);
252
253	/* Reset IV to original value */
254	EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, NULL);
255	/* Decrypt again */
256	EVP_DecryptUpdate(ctx, tmp, &outl, tmp, inlen);
257	/* Check check bytes */
258	if (((tmp[1] ^ tmp[4]) & (tmp[2] ^ tmp[5]) & (tmp[3] ^ tmp[6])) != 0xff)
259		{
260		/* Check byte failure */
261		goto err;
262		}
263	if (inlen < (size_t)(tmp[0] - 4 ))
264		{
265		/* Invalid length value */
266		goto err;
267		}
268	*outlen = (size_t)tmp[0];
269	memcpy(out, tmp + 4, *outlen);
270	rv = 1;
271	err:
272	OPENSSL_cleanse(tmp, inlen);
273	OPENSSL_free(tmp);
274	return rv;
275
276	}
277
278static int kek_wrap_key(unsigned char *out, size_t *outlen,
279		const unsigned char *in, size_t inlen, EVP_CIPHER_CTX *ctx)
280	{
281	size_t blocklen = EVP_CIPHER_CTX_block_size(ctx);
282	size_t olen;
283	int dummy;
284	/* First decide length of output buffer: need header and round up to
285	 * multiple of block length.
286	 */
287	olen = (inlen + 4 + blocklen - 1)/blocklen;
288	olen *= blocklen;
289	if (olen < 2 * blocklen)
290		{
291		/* Key too small */
292		return 0;
293		}
294	if (inlen > 0xFF)
295		{
296		/* Key too large */
297		return 0;
298		}
299	if (out)
300		{
301		/* Set header */
302		out[0] = (unsigned char)inlen;
303		out[1] = in[0] ^ 0xFF;
304		out[2] = in[1] ^ 0xFF;
305		out[3] = in[2] ^ 0xFF;
306		memcpy(out + 4, in, inlen);
307		/* Add random padding to end */
308		if (olen > inlen + 4)
309			RAND_pseudo_bytes(out + 4 + inlen, olen - 4 - inlen);
310		/* Encrypt twice */
311		EVP_EncryptUpdate(ctx, out, &dummy, out, olen);
312		EVP_EncryptUpdate(ctx, out, &dummy, out, olen);
313		}
314
315	*outlen = olen;
316
317	return 1;
318	}
319
320/* Encrypt/Decrypt content key in PWRI recipient info */
321
322int cms_RecipientInfo_pwri_crypt(CMS_ContentInfo *cms, CMS_RecipientInfo *ri,
323							int en_de)
324	{
325	CMS_EncryptedContentInfo *ec;
326	CMS_PasswordRecipientInfo *pwri;
327	const unsigned char *p = NULL;
328	int plen;
329	int r = 0;
330	X509_ALGOR *algtmp, *kekalg = NULL;
331	EVP_CIPHER_CTX kekctx;
332	const EVP_CIPHER *kekcipher;
333	unsigned char *key = NULL;
334	size_t keylen;
335
336	ec = cms->d.envelopedData->encryptedContentInfo;
337
338	pwri = ri->d.pwri;
339	EVP_CIPHER_CTX_init(&kekctx);
340
341	if (!pwri->pass)
342		{
343		CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT, CMS_R_NO_PASSWORD);
344		return 0;
345		}
346	algtmp = pwri->keyEncryptionAlgorithm;
347
348	if (!algtmp || OBJ_obj2nid(algtmp->algorithm) != NID_id_alg_PWRI_KEK)
349		{
350		CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT,
351				CMS_R_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM);
352		return 0;
353		}
354
355	if (algtmp->parameter->type == V_ASN1_SEQUENCE)
356		{
357		p = algtmp->parameter->value.sequence->data;
358		plen = algtmp->parameter->value.sequence->length;
359		kekalg = d2i_X509_ALGOR(NULL, &p, plen);
360		}
361	if (kekalg == NULL)
362		{
363		CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT,
364				CMS_R_INVALID_KEY_ENCRYPTION_PARAMETER);
365		return 0;
366		}
367
368	kekcipher = EVP_get_cipherbyobj(kekalg->algorithm);
369
370	if(!kekcipher)
371		{
372		CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT,
373				CMS_R_UNKNOWN_CIPHER);
374		goto err;
375		}
376
377	/* Fixup cipher based on AlgorithmIdentifier to set IV etc */
378	if (!EVP_CipherInit_ex(&kekctx, kekcipher, NULL, NULL, NULL, en_de))
379		goto err;
380	EVP_CIPHER_CTX_set_padding(&kekctx, 0);
381	if(EVP_CIPHER_asn1_to_param(&kekctx, kekalg->parameter) < 0)
382		{
383		CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT,
384				CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
385		goto err;
386		}
387
388	algtmp = pwri->keyDerivationAlgorithm;
389
390	/* Finish password based key derivation to setup key in "ctx" */
391
392	if (EVP_PBE_CipherInit(algtmp->algorithm,
393				(char *)pwri->pass, pwri->passlen,
394				algtmp->parameter, &kekctx, en_de) < 0)
395		{
396		CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT, ERR_R_EVP_LIB);
397		goto err;
398		}
399
400	/* Finally wrap/unwrap the key */
401
402	if (en_de)
403		{
404
405		if (!kek_wrap_key(NULL, &keylen, ec->key, ec->keylen, &kekctx))
406			goto err;
407
408		key = OPENSSL_malloc(keylen);
409
410		if (!key)
411			goto err;
412
413		if (!kek_wrap_key(key, &keylen, ec->key, ec->keylen, &kekctx))
414			goto err;
415		pwri->encryptedKey->data = key;
416		pwri->encryptedKey->length = keylen;
417		}
418	else
419		{
420		key = OPENSSL_malloc(pwri->encryptedKey->length);
421
422		if (!key)
423			{
424			CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT,
425							ERR_R_MALLOC_FAILURE);
426			goto err;
427			}
428		if (!kek_unwrap_key(key, &keylen,
429					pwri->encryptedKey->data,
430					pwri->encryptedKey->length, &kekctx))
431			{
432			CMSerr(CMS_F_CMS_RECIPIENTINFO_PWRI_CRYPT,
433							CMS_R_UNWRAP_FAILURE);
434			goto err;
435			}
436
437		ec->key = key;
438		ec->keylen = keylen;
439
440		}
441
442	r = 1;
443
444	err:
445
446	EVP_CIPHER_CTX_cleanup(&kekctx);
447
448	if (!r && key)
449		OPENSSL_free(key);
450	X509_ALGOR_free(kekalg);
451
452	return r;
453
454	}
455