aboutsummaryrefslogtreecommitdiffstats
path: root/fs/cifs/smbencrypt.c
blob: 1525d5e662b65cd11649587458013bd47dc7fc2a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
/*
   Unix SMB/Netbios implementation.
   Version 1.9.
   SMB parameters and setup
   Copyright (C) Andrew Tridgell 1992-2000
   Copyright (C) Luke Kenneth Casson Leighton 1996-2000
   Modified by Jeremy Allison 1995.
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2002-2003
   Modified by Steve French (sfrench@us.ibm.com) 2002-2003

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/random.h>
#include "cifs_unicode.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifs_debug.h"
#include "cifsproto.h"

#ifndef false
#define false 0
#endif
#ifndef true
#define true 1
#endif

/* following came from the other byteorder.h to avoid include conflicts */
#define CVAL(buf,pos) (((unsigned char *)(buf))[pos])
#define SSVALX(buf,pos,val) (CVAL(buf,pos)=(val)&0xFF,CVAL(buf,pos+1)=(val)>>8)
#define SSVAL(buf,pos,val) SSVALX((buf),(pos),((__u16)(val)))

static void
str_to_key(unsigned char *str, unsigned char *key)
{
	int i;

	key[0] = str[0] >> 1;
	key[1] = ((str[0] & 0x01) << 6) | (str[1] >> 2);
	key[2] = ((str[1] & 0x03) << 5) | (str[2] >> 3);
	key[3] = ((str[2] & 0x07) << 4) | (str[3] >> 4);
	key[4] = ((str[3] & 0x0F) << 3) | (str[4] >> 5);
	key[5] = ((str[4] & 0x1F) << 2) | (str[5] >> 6);
	key[6] = ((str[5] & 0x3F) << 1) | (str[6] >> 7);
	key[7] = str[6] & 0x7F;
	for (i = 0; i < 8; i++)
		key[i] = (key[i] << 1);
}

static int
smbhash(unsigned char *out, const unsigned char *in, unsigned char *key)
{
	int rc;
	unsigned char key2[8];
	struct crypto_blkcipher *tfm_des;
	struct scatterlist sgin, sgout;
	struct blkcipher_desc desc;

	str_to_key(key, key2);

	tfm_des = crypto_alloc_blkcipher("ecb(des)", 0, CRYPTO_ALG_ASYNC);
	if (IS_ERR(tfm_des)) {
		rc = PTR_ERR(tfm_des);
		cERROR(1, "could not allocate des crypto API\n");
		goto smbhash_err;
	}

	desc.tfm = tfm_des;

	crypto_blkcipher_setkey(tfm_des, key2, 8);

	sg_init_one(&sgin, in, 8);
	sg_init_one(&sgout, out, 8);

	rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, 8);
	if (rc) {
		cERROR(1, "could not encrypt crypt key rc: %d\n", rc);
		crypto_free_blkcipher(tfm_des);
		goto smbhash_err;
	}

smbhash_err:
	return rc;
}

static int
E_P16(unsigned char *p14, unsigned char *p16)
{
	int rc;
	unsigned char sp8[8] =
	    { 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };

	rc = smbhash(p16, sp8, p14);
	if (rc)
		return rc;
	rc = smbhash(p16 + 8, sp8, p14 + 7);
	return rc;
}

static int
E_P24(unsigned char *p21, const unsigned char *c8, unsigned char *p24)
{
	int rc;

	rc = smbhash(p24, c8, p21);
	if (rc)
		return rc;
	rc = smbhash(p24 + 8, c8, p21 + 7);
	if (rc)
		return rc;
	rc = smbhash(p24 + 16, c8, p21 + 14);
	return rc;
}

/* produce a md4 message digest from data of length n bytes */
int
mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
{
	int rc;
	unsigned int size;
	struct crypto_shash *md4;
	struct sdesc *sdescmd4;

	md4 = crypto_alloc_shash("md4", 0, 0);
	if (IS_ERR(md4)) {
		rc = PTR_ERR(md4);
		cERROR(1, "%s: Crypto md4 allocation error %d\n", __func__, rc);
		return rc;
	}
	size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
	sdescmd4 = kmalloc(size, GFP_KERNEL);
	if (!sdescmd4) {
		rc = -ENOMEM;
		cERROR(1, "%s: Memory allocation failure\n", __func__);
		goto mdfour_err;
	}
	sdescmd4->shash.tfm = md4;
	sdescmd4->shash.flags = 0x0;

	rc = crypto_shash_init(&sdescmd4->shash);
	if (rc) {
		cERROR(1, "%s: Could not init md4 shash\n", __func__);
		goto mdfour_err;
	}
	crypto_shash_update(&sdescmd4->shash, link_str, link_len);
	rc = crypto_shash_final(&sdescmd4->shash, md4_hash);

mdfour_err:
	crypto_free_shash(md4);
	kfree(sdescmd4);

	return rc;
}

/*
   This implements the X/Open SMB password encryption
   It takes a password, a 8 byte "crypt key" and puts 24 bytes of
   encrypted password into p24 */
/* Note that password must be uppercased and null terminated */
int
SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24)
{
	int rc;
	unsigned char p14[14], p16[16], p21[21];

	memset(p14, '\0', 14);
	memset(p16, '\0', 16);
	memset(p21, '\0', 21);

	memcpy(p14, passwd, 14);
	rc = E_P16(p14, p16);
	if (rc)
		return rc;

	memcpy(p21, p16, 16);
	rc = E_P24(p21, c8, p24);

	return rc;
}

/* Routines for Windows NT MD4 Hash functions. */
static int
_my_wcslen(__u16 *str)
{
	int len = 0;
	while (*str++ != 0)
		len++;
	return len;
}

/*
 * Convert a string into an NT UNICODE string.
 * Note that regardless of processor type
 * this must be in intel (little-endian)
 * format.
 */

static int
_my_mbstowcs(__u16 *dst, const unsigned char *src, int len)
{	/* BB not a very good conversion routine - change/fix */
	int i;
	__u16 val;

	for (i = 0; i < len; i++) {
		val = *src;
		SSVAL(dst, 0, val);
		dst++;
		src++;
		if (val == 0)
			break;
	}
	return i;
}

/*
 * Creates the MD4 Hash of the users password in NT UNICODE.
 */

int
E_md4hash(const unsigned char *passwd, unsigned char *p16)
{
	int rc;
	int len;
	__u16 wpwd[129];

	/* Password cannot be longer than 128 characters */
	if (passwd) {
		len = strlen((char *) passwd);
		if (len > 128)
			len = 128;

		/* Password must be converted to NT unicode */
		_my_mbstowcs(wpwd, passwd, len);
	} else
		len = 0;

	wpwd[len] = 0;	/* Ensure string is null terminated */
	/* Calculate length in bytes */
	len = _my_wcslen(wpwd) * sizeof(__u16);

	rc = mdfour(p16, (unsigned char *) wpwd, len);
	memset(wpwd, 0, 129 * 2);

	return rc;
}

#if 0 /* currently unused */
/* Does both the NT and LM owfs of a user's password */
static void
nt_lm_owf_gen(char *pwd, unsigned char nt_p16[16], unsigned char p16[16])
{
	char passwd[514];

	memset(passwd, '\0', 514);
	if (strlen(pwd) < 513)
		strcpy(passwd, pwd);
	else
		memcpy(passwd, pwd, 512);
	/* Calculate the MD4 hash (NT compatible) of the password */
	memset(nt_p16, '\0', 16);
	E_md4hash(passwd, nt_p16);

	/* Mangle the passwords into Lanman format */
	passwd[14] = '\0';
/*	strupper(passwd); */

	/* Calculate the SMB (lanman) hash functions of the password */

	memset(p16, '\0', 16);
	E_P16((unsigned char *) passwd, (unsigned char *) p16);

	/* clear out local copy of user's password (just being paranoid). */
	memset(passwd, '\0', sizeof(passwd));
}
#endif

/* Does the NTLMv2 owfs of a user's password */
#if 0  /* function not needed yet - but will be soon */
static void
ntv2_owf_gen(const unsigned char owf[16], const char *user_n,
		const char *domain_n, unsigned char kr_buf[16],
		const struct nls_table *nls_codepage)
{
	wchar_t *user_u;
	wchar_t *dom_u;
	int user_l, domain_l;
	struct HMACMD5Context ctx;

	/* might as well do one alloc to hold both (user_u and dom_u) */
	user_u = kmalloc(2048 * sizeof(wchar_t), GFP_KERNEL);
	if (user_u == NULL)
		return;
	dom_u = user_u + 1024;

	/* push_ucs2(NULL, user_u, user_n, (user_l+1)*2,
			STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER);
	   push_ucs2(NULL, dom_u, domain_n, (domain_l+1)*2,
			STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER); */

	/* BB user and domain may need to be uppercased */
	user_l = cifs_strtoUCS(user_u, user_n, 511, nls_codepage);
	domain_l = cifs_strtoUCS(dom_u, domain_n, 511, nls_codepage);

	user_l++;		/* trailing null */
	domain_l++;

	hmac_md5_init_limK_to_64(owf, 16, &ctx);
	hmac_md5_update((const unsigned char *) user_u, user_l * 2, &ctx);
	hmac_md5_update((const unsigned char *) dom_u, domain_l * 2, &ctx);
	hmac_md5_final(kr_buf, &ctx);

	kfree(user_u);
}
#endif

/* Does the des encryption from the FIRST 8 BYTES of the NT or LM MD4 hash. */
#if 0 /* currently unused */
static void
NTLMSSPOWFencrypt(unsigned char passwd[8],
		  unsigned char *ntlmchalresp, unsigned char p24[24])
{
	unsigned char p21[21];

	memset(p21, '\0', 21);
	memcpy(p21, passwd, 8);
	memset(p21 + 8, 0xbd, 8);

	E_P24(p21, ntlmchalresp, p24);
}
#endif

/* Does the NT MD4 hash then des encryption. */
int
SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24)
{
	int rc;
	unsigned char p16[16], p21[21];

	memset(p16, '\0', 16);
	memset(p21, '\0', 21);

	rc = E_md4hash(passwd, p16);
	if (rc) {
		cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
		return rc;
	}
	memcpy(p21, p16, 16);
	rc = E_P24(p21, c8, p24);
	return rc;
}


/* Does the md5 encryption from the NT hash for NTLMv2. */
/* These routines will be needed later */
#if 0
static void
SMBOWFencrypt_ntv2(const unsigned char kr[16],
		   const struct data_blob *srv_chal,
		   const struct data_blob *cli_chal, unsigned char resp_buf[16])
{
	struct HMACMD5Context ctx;

	hmac_md5_init_limK_to_64(kr, 16, &ctx);
	hmac_md5_update(srv_chal->data, srv_chal->length, &ctx);
	hmac_md5_update(cli_chal->data, cli_chal->length, &ctx);
	hmac_md5_final(resp_buf, &ctx);
}

static void
SMBsesskeygen_ntv2(const unsigned char kr[16],
		   const unsigned char *nt_resp, __u8 sess_key[16])
{
	struct HMACMD5Context ctx;

	hmac_md5_init_limK_to_64(kr, 16, &ctx);
	hmac_md5_update(nt_resp, 16, &ctx);
	hmac_md5_final((unsigned char *) sess_key, &ctx);
}

static void
SMBsesskeygen_ntv1(const unsigned char kr[16],
		   const unsigned char *nt_resp, __u8 sess_key[16])
{
	mdfour((unsigned char *) sess_key, (unsigned char *) kr, 16);
}
#endif