1 /*
2 Unix SMB/Netbios implementation.
3 Version 1.9.
4 SMB parameters and setup
5 Copyright (C) Andrew Tridgell 1992-2000
6 Copyright (C) Luke Kenneth Casson Leighton 1996-2000
7 Modified by Jeremy Allison 1995.
8 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2002-2003
9 Modified by Steve French (sfrench@us.ibm.com) 2002-2003
10
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 2 of the License, or
14 (at your option) any later version.
15
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License for more details.
20
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software
23 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 */
25
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/fs.h>
29 #include <linux/string.h>
30 #include <linux/kernel.h>
31 #include <linux/random.h>
32 #include "cifs_fs_sb.h"
33 #include "cifs_unicode.h"
34 #include "cifspdu.h"
35 #include "cifsglob.h"
36 #include "cifs_debug.h"
37 #include "cifsproto.h"
38
39 #ifndef false
40 #define false 0
41 #endif
42 #ifndef true
43 #define true 1
44 #endif
45
46 /* following came from the other byteorder.h to avoid include conflicts */
47 #define CVAL(buf,pos) (((unsigned char *)(buf))[pos])
48 #define SSVALX(buf,pos,val) (CVAL(buf,pos)=(val)&0xFF,CVAL(buf,pos+1)=(val)>>8)
49 #define SSVAL(buf,pos,val) SSVALX((buf),(pos),((__u16)(val)))
50
51 static void
str_to_key(unsigned char * str,unsigned char * key)52 str_to_key(unsigned char *str, unsigned char *key)
53 {
54 int i;
55
56 key[0] = str[0] >> 1;
57 key[1] = ((str[0] & 0x01) << 6) | (str[1] >> 2);
58 key[2] = ((str[1] & 0x03) << 5) | (str[2] >> 3);
59 key[3] = ((str[2] & 0x07) << 4) | (str[3] >> 4);
60 key[4] = ((str[3] & 0x0F) << 3) | (str[4] >> 5);
61 key[5] = ((str[4] & 0x1F) << 2) | (str[5] >> 6);
62 key[6] = ((str[5] & 0x3F) << 1) | (str[6] >> 7);
63 key[7] = str[6] & 0x7F;
64 for (i = 0; i < 8; i++)
65 key[i] = (key[i] << 1);
66 }
67
68 static int
smbhash(unsigned char * out,const unsigned char * in,unsigned char * key)69 smbhash(unsigned char *out, const unsigned char *in, unsigned char *key)
70 {
71 int rc;
72 unsigned char key2[8];
73 struct crypto_blkcipher *tfm_des;
74 struct scatterlist sgin, sgout;
75 struct blkcipher_desc desc;
76
77 str_to_key(key, key2);
78
79 tfm_des = crypto_alloc_blkcipher("ecb(des)", 0, CRYPTO_ALG_ASYNC);
80 if (IS_ERR(tfm_des)) {
81 rc = PTR_ERR(tfm_des);
82 cifs_dbg(VFS, "could not allocate des crypto API\n");
83 goto smbhash_err;
84 }
85
86 desc.tfm = tfm_des;
87
88 crypto_blkcipher_setkey(tfm_des, key2, 8);
89
90 sg_init_one(&sgin, in, 8);
91 sg_init_one(&sgout, out, 8);
92
93 rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, 8);
94 if (rc)
95 cifs_dbg(VFS, "could not encrypt crypt key rc: %d\n", rc);
96
97 crypto_free_blkcipher(tfm_des);
98 smbhash_err:
99 return rc;
100 }
101
102 static int
E_P16(unsigned char * p14,unsigned char * p16)103 E_P16(unsigned char *p14, unsigned char *p16)
104 {
105 int rc;
106 unsigned char sp8[8] =
107 { 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };
108
109 rc = smbhash(p16, sp8, p14);
110 if (rc)
111 return rc;
112 rc = smbhash(p16 + 8, sp8, p14 + 7);
113 return rc;
114 }
115
116 static int
E_P24(unsigned char * p21,const unsigned char * c8,unsigned char * p24)117 E_P24(unsigned char *p21, const unsigned char *c8, unsigned char *p24)
118 {
119 int rc;
120
121 rc = smbhash(p24, c8, p21);
122 if (rc)
123 return rc;
124 rc = smbhash(p24 + 8, c8, p21 + 7);
125 if (rc)
126 return rc;
127 rc = smbhash(p24 + 16, c8, p21 + 14);
128 return rc;
129 }
130
131 /* produce a md4 message digest from data of length n bytes */
132 int
mdfour(unsigned char * md4_hash,unsigned char * link_str,int link_len)133 mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
134 {
135 int rc;
136 unsigned int size;
137 struct crypto_shash *md4;
138 struct sdesc *sdescmd4;
139
140 md4 = crypto_alloc_shash("md4", 0, 0);
141 if (IS_ERR(md4)) {
142 rc = PTR_ERR(md4);
143 cifs_dbg(VFS, "%s: Crypto md4 allocation error %d\n",
144 __func__, rc);
145 return rc;
146 }
147 size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
148 sdescmd4 = kmalloc(size, GFP_KERNEL);
149 if (!sdescmd4) {
150 rc = -ENOMEM;
151 goto mdfour_err;
152 }
153 sdescmd4->shash.tfm = md4;
154 sdescmd4->shash.flags = 0x0;
155
156 rc = crypto_shash_init(&sdescmd4->shash);
157 if (rc) {
158 cifs_dbg(VFS, "%s: Could not init md4 shash\n", __func__);
159 goto mdfour_err;
160 }
161 rc = crypto_shash_update(&sdescmd4->shash, link_str, link_len);
162 if (rc) {
163 cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
164 goto mdfour_err;
165 }
166 rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
167 if (rc)
168 cifs_dbg(VFS, "%s: Could not generate md4 hash\n", __func__);
169
170 mdfour_err:
171 crypto_free_shash(md4);
172 kfree(sdescmd4);
173
174 return rc;
175 }
176
177 /*
178 This implements the X/Open SMB password encryption
179 It takes a password, a 8 byte "crypt key" and puts 24 bytes of
180 encrypted password into p24 */
181 /* Note that password must be uppercased and null terminated */
182 int
SMBencrypt(unsigned char * passwd,const unsigned char * c8,unsigned char * p24)183 SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24)
184 {
185 int rc;
186 unsigned char p14[14], p16[16], p21[21];
187
188 memset(p14, '\0', 14);
189 memset(p16, '\0', 16);
190 memset(p21, '\0', 21);
191
192 memcpy(p14, passwd, 14);
193 rc = E_P16(p14, p16);
194 if (rc)
195 return rc;
196
197 memcpy(p21, p16, 16);
198 rc = E_P24(p21, c8, p24);
199
200 return rc;
201 }
202
203 /*
204 * Creates the MD4 Hash of the users password in NT UNICODE.
205 */
206
207 int
E_md4hash(const unsigned char * passwd,unsigned char * p16,const struct nls_table * codepage)208 E_md4hash(const unsigned char *passwd, unsigned char *p16,
209 const struct nls_table *codepage)
210 {
211 int rc;
212 int len;
213 __le16 wpwd[129];
214
215 /* Password cannot be longer than 128 characters */
216 if (passwd) /* Password must be converted to NT unicode */
217 len = cifs_strtoUTF16(wpwd, passwd, 128, codepage);
218 else {
219 len = 0;
220 *wpwd = 0; /* Ensure string is null terminated */
221 }
222
223 rc = mdfour(p16, (unsigned char *) wpwd, len * sizeof(__le16));
224 memzero_explicit(wpwd, sizeof(wpwd));
225
226 return rc;
227 }
228
229 /* Does the NT MD4 hash then des encryption. */
230 int
SMBNTencrypt(unsigned char * passwd,unsigned char * c8,unsigned char * p24,const struct nls_table * codepage)231 SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24,
232 const struct nls_table *codepage)
233 {
234 int rc;
235 unsigned char p16[16], p21[21];
236
237 memset(p16, '\0', 16);
238 memset(p21, '\0', 21);
239
240 rc = E_md4hash(passwd, p16, codepage);
241 if (rc) {
242 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
243 __func__, rc);
244 return rc;
245 }
246 memcpy(p21, p16, 16);
247 rc = E_P24(p21, c8, p24);
248 return rc;
249 }
250