1/*-
2 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
3 * Authors: Doug Rabson <dfr@rabson.org>
4 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/lock.h>
33#include <sys/kobj.h>
34#include <sys/malloc.h>
35#include <sys/md5.h>
36#include <sys/mutex.h>
37#include <sys/mbuf.h>
38#include <crypto/des/des.h>
39#include <opencrypto/cryptodev.h>
40
41#include <kgssapi/gssapi.h>
42#include <kgssapi/gssapi_impl.h>
43
44#include "kcrypto.h"
45
46struct des1_state {
47	struct mtx	ds_lock;
48	uint64_t	ds_session;
49};
50
51static void
52des1_init(struct krb5_key_state *ks)
53{
54	struct des1_state *ds;
55
56	ds = malloc(sizeof(struct des1_state), M_GSSAPI, M_WAITOK|M_ZERO);
57	mtx_init(&ds->ds_lock, "gss des lock", NULL, MTX_DEF);
58	ks->ks_priv = ds;
59}
60
61static void
62des1_destroy(struct krb5_key_state *ks)
63{
64	struct des1_state *ds = ks->ks_priv;
65
66	if (ds->ds_session)
67		crypto_freesession(ds->ds_session);
68	mtx_destroy(&ds->ds_lock);
69	free(ks->ks_priv, M_GSSAPI);
70
71}
72
73static void
74des1_set_key(struct krb5_key_state *ks, const void *in)
75{
76	void *kp = ks->ks_key;
77	struct des1_state *ds = ks->ks_priv;
78	struct cryptoini cri[1];
79
80	if (kp != in)
81		bcopy(in, kp, ks->ks_class->ec_keylen);
82
83	if (ds->ds_session)
84		crypto_freesession(ds->ds_session);
85
86	bzero(cri, sizeof(cri));
87
88	cri[0].cri_alg = CRYPTO_DES_CBC;
89	cri[0].cri_klen = 64;
90	cri[0].cri_mlen = 0;
91	cri[0].cri_key = ks->ks_key;
92	cri[0].cri_next = NULL;
93
94	crypto_newsession(&ds->ds_session, cri,
95	    CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE);
96}
97
98static void
99des1_random_to_key(struct krb5_key_state *ks, const void *in)
100{
101	uint8_t *outkey = ks->ks_key;
102	const uint8_t *inkey = in;
103
104	/*
105	 * Expand 56 bits of random data to 64 bits as follows
106	 * (in the example, bit number 1 is the MSB of the 56
107	 * bits of random data):
108	 *
109	 * expanded =
110	 *	 1  2  3  4  5  6  7  p
111	 *	 9 10 11 12 13 14 15  p
112	 *	17 18 19 20 21 22 23  p
113	 *	25 26 27 28 29 30 31  p
114	 *	33 34 35 36 37 38 39  p
115	 *	41 42 43 44 45 46 47  p
116	 *	49 50 51 52 53 54 55  p
117	 *	56 48 40 32 24 16  8  p
118	 */
119	outkey[0] = inkey[0];
120	outkey[1] = inkey[1];
121	outkey[2] = inkey[2];
122	outkey[3] = inkey[3];
123	outkey[4] = inkey[4];
124	outkey[5] = inkey[5];
125	outkey[6] = inkey[6];
126	outkey[7] = (((inkey[0] & 1) << 1)
127	    | ((inkey[1] & 1) << 2)
128	    | ((inkey[2] & 1) << 3)
129	    | ((inkey[3] & 1) << 4)
130	    | ((inkey[4] & 1) << 5)
131	    | ((inkey[5] & 1) << 6)
132	    | ((inkey[6] & 1) << 7));
133	des_set_odd_parity((des_cblock *) outkey);
134	if (des_is_weak_key((des_cblock *) outkey))
135		outkey[7] ^= 0xf0;
136
137	des1_set_key(ks, ks->ks_key);
138}
139
140static int
141des1_crypto_cb(struct cryptop *crp)
142{
143	int error;
144	struct des1_state *ds = (struct des1_state *) crp->crp_opaque;
145
146	if (CRYPTO_SESID2CAPS(ds->ds_session) & CRYPTOCAP_F_SYNC)
147		return (0);
148
149	error = crp->crp_etype;
150	if (error == EAGAIN)
151		error = crypto_dispatch(crp);
152	mtx_lock(&ds->ds_lock);
153	if (error || (crp->crp_flags & CRYPTO_F_DONE))
154		wakeup(crp);
155	mtx_unlock(&ds->ds_lock);
156
157	return (0);
158}
159
160static void
161des1_encrypt_1(const struct krb5_key_state *ks, int buftype, void *buf,
162    size_t skip, size_t len, void *ivec, int encdec)
163{
164	struct des1_state *ds = ks->ks_priv;
165	struct cryptop *crp;
166	struct cryptodesc *crd;
167	int error;
168
169	crp = crypto_getreq(1);
170	crd = crp->crp_desc;
171
172	crd->crd_skip = skip;
173	crd->crd_len = len;
174	crd->crd_flags = CRD_F_IV_EXPLICIT | CRD_F_IV_PRESENT | encdec;
175	if (ivec) {
176		bcopy(ivec, crd->crd_iv, 8);
177	} else {
178		bzero(crd->crd_iv, 8);
179	}
180	crd->crd_next = NULL;
181	crd->crd_alg = CRYPTO_DES_CBC;
182
183	crp->crp_sid = ds->ds_session;
184	crp->crp_flags = buftype | CRYPTO_F_CBIFSYNC;
185	crp->crp_buf = buf;
186	crp->crp_opaque = (void *) ds;
187	crp->crp_callback = des1_crypto_cb;
188
189	error = crypto_dispatch(crp);
190
191	if ((CRYPTO_SESID2CAPS(ds->ds_session) & CRYPTOCAP_F_SYNC) == 0) {
192		mtx_lock(&ds->ds_lock);
193		if (!error && !(crp->crp_flags & CRYPTO_F_DONE))
194			error = msleep(crp, &ds->ds_lock, 0, "gssdes", 0);
195		mtx_unlock(&ds->ds_lock);
196	}
197
198	crypto_freereq(crp);
199}
200
201static void
202des1_encrypt(const struct krb5_key_state *ks, struct mbuf *inout,
203    size_t skip, size_t len, void *ivec, size_t ivlen)
204{
205
206	des1_encrypt_1(ks, CRYPTO_F_IMBUF, inout, skip, len, ivec,
207	    CRD_F_ENCRYPT);
208}
209
210static void
211des1_decrypt(const struct krb5_key_state *ks, struct mbuf *inout,
212    size_t skip, size_t len, void *ivec, size_t ivlen)
213{
214
215	des1_encrypt_1(ks, CRYPTO_F_IMBUF, inout, skip, len, ivec, 0);
216}
217
218static int
219MD5Update_int(void *ctx, void *buf, u_int len)
220{
221
222	MD5Update(ctx, buf, len);
223	return (0);
224}
225
226static void
227des1_checksum(const struct krb5_key_state *ks, int usage,
228    struct mbuf *inout, size_t skip, size_t inlen, size_t outlen)
229{
230	char hash[16];
231	MD5_CTX md5;
232
233	/*
234	 * This checksum is specifically for GSS-API. First take the
235	 * MD5 checksum of the message, then calculate the CBC mode
236	 * checksum of that MD5 checksum using a zero IV.
237	 */
238	MD5Init(&md5);
239	m_apply(inout, skip, inlen, MD5Update_int, &md5);
240	MD5Final(hash, &md5);
241
242	des1_encrypt_1(ks, 0, hash, 0, 16, NULL, CRD_F_ENCRYPT);
243	m_copyback(inout, skip + inlen, outlen, hash + 8);
244}
245
246struct krb5_encryption_class krb5_des_encryption_class = {
247	"des-cbc-md5",		/* name */
248	ETYPE_DES_CBC_CRC,	/* etype */
249	0,			/* flags */
250	8,			/* blocklen */
251	8,			/* msgblocklen */
252	8,			/* checksumlen */
253	56,			/* keybits */
254	8,			/* keylen */
255	des1_init,
256	des1_destroy,
257	des1_set_key,
258	des1_random_to_key,
259	des1_encrypt,
260	des1_decrypt,
261	des1_checksum
262};
263