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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * fs/cifs/cifsencrypt.c
3 *
Steve French12b3b8f2006-02-09 21:12:47 +00004 * Copyright (C) International Business Machines Corp., 2005,2006
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/fs.h>
23#include "cifspdu.h"
24#include "cifsglob.h"
25#include "cifs_debug.h"
26#include "md5.h"
27#include "cifs_unicode.h"
28#include "cifsproto.h"
Steve French7c7b25b2006-06-01 19:20:10 +000029#include <linux/ctype.h>
Steve French6d027cf2006-06-05 16:26:05 +000030#include <linux/random.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32/* Calculate and return the CIFS signature based on the mac key and the smb pdu */
33/* the 16 byte signature must be allocated by the caller */
34/* Note we only use the 1st eight bytes */
35/* Note that the smb header signature field on input contains the
36 sequence number before this function is called */
37
38extern void mdfour(unsigned char *out, unsigned char *in, int n);
39extern void E_md4hash(const unsigned char *passwd, unsigned char *p16);
Steve French7c7b25b2006-06-01 19:20:10 +000040extern void SMBencrypt(unsigned char *passwd, unsigned char *c8,
41 unsigned char *p24);
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
Steve French12b3b8f2006-02-09 21:12:47 +000043static int cifs_calculate_signature(const struct smb_hdr * cifs_pdu,
44 const char * key, char * signature)
Linus Torvalds1da177e2005-04-16 15:20:36 -070045{
46 struct MD5Context context;
47
48 if((cifs_pdu == NULL) || (signature == NULL))
49 return -EINVAL;
50
51 MD5Init(&context);
Steve French7c7b25b2006-06-01 19:20:10 +000052 MD5Update(&context,key,CIFS_SESS_KEY_SIZE+16);
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 MD5Update(&context,cifs_pdu->Protocol,cifs_pdu->smb_buf_length);
54 MD5Final(signature,&context);
55 return 0;
56}
57
Steve Frenchad009ac2005-04-28 22:41:05 -070058int cifs_sign_smb(struct smb_hdr * cifs_pdu, struct TCP_Server_Info * server,
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 __u32 * pexpected_response_sequence_number)
60{
61 int rc = 0;
62 char smb_signature[20];
63
Steve Frenchad009ac2005-04-28 22:41:05 -070064 if((cifs_pdu == NULL) || (server == NULL))
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 return -EINVAL;
66
67 if((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
68 return rc;
69
70 spin_lock(&GlobalMid_Lock);
Steve Frenchad009ac2005-04-28 22:41:05 -070071 cifs_pdu->Signature.Sequence.SequenceNumber = cpu_to_le32(server->sequence_number);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 cifs_pdu->Signature.Sequence.Reserved = 0;
73
Steve Frenchad009ac2005-04-28 22:41:05 -070074 *pexpected_response_sequence_number = server->sequence_number++;
75 server->sequence_number++;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 spin_unlock(&GlobalMid_Lock);
77
Steve Frenchad009ac2005-04-28 22:41:05 -070078 rc = cifs_calculate_signature(cifs_pdu, server->mac_signing_key,smb_signature);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 if(rc)
80 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
81 else
82 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
83
84 return rc;
85}
86
Steve French84afc292005-12-02 13:32:45 -080087static int cifs_calc_signature2(const struct kvec * iov, int n_vec,
88 const char * key, char * signature)
89{
Steve Frenche9917a02006-03-31 21:22:00 +000090 struct MD5Context context;
91 int i;
Steve French84afc292005-12-02 13:32:45 -080092
Steve Frenche9917a02006-03-31 21:22:00 +000093 if((iov == NULL) || (signature == NULL))
94 return -EINVAL;
Steve French84afc292005-12-02 13:32:45 -080095
Steve Frenche9917a02006-03-31 21:22:00 +000096 MD5Init(&context);
Steve French7c7b25b2006-06-01 19:20:10 +000097 MD5Update(&context,key,CIFS_SESS_KEY_SIZE+16);
Steve Frenche9917a02006-03-31 21:22:00 +000098 for(i=0;i<n_vec;i++) {
99 if(iov[i].iov_base == NULL) {
100 cERROR(1,("null iovec entry"));
101 return -EIO;
102 } else if(iov[i].iov_len == 0)
103 break; /* bail out if we are sent nothing to sign */
104 /* The first entry includes a length field (which does not get
105 signed that occupies the first 4 bytes before the header */
106 if(i==0) {
107 if (iov[0].iov_len <= 8 ) /* cmd field at offset 9 */
108 break; /* nothing to sign or corrupt header */
109 MD5Update(&context,iov[0].iov_base+4, iov[0].iov_len-4);
110 } else
111 MD5Update(&context,iov[i].iov_base, iov[i].iov_len);
112 }
Steve French84afc292005-12-02 13:32:45 -0800113
Steve Frenche9917a02006-03-31 21:22:00 +0000114 MD5Final(signature,&context);
Steve French84afc292005-12-02 13:32:45 -0800115
Steve Frenche9917a02006-03-31 21:22:00 +0000116 return 0;
Steve French84afc292005-12-02 13:32:45 -0800117}
118
119
120int cifs_sign_smb2(struct kvec * iov, int n_vec, struct TCP_Server_Info *server,
121 __u32 * pexpected_response_sequence_number)
122{
123 int rc = 0;
124 char smb_signature[20];
125 struct smb_hdr * cifs_pdu = iov[0].iov_base;
126
127 if((cifs_pdu == NULL) || (server == NULL))
128 return -EINVAL;
129
130 if((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
131 return rc;
132
133 spin_lock(&GlobalMid_Lock);
134 cifs_pdu->Signature.Sequence.SequenceNumber =
135 cpu_to_le32(server->sequence_number);
136 cifs_pdu->Signature.Sequence.Reserved = 0;
137
138 *pexpected_response_sequence_number = server->sequence_number++;
139 server->sequence_number++;
140 spin_unlock(&GlobalMid_Lock);
141
142 rc = cifs_calc_signature2(iov, n_vec, server->mac_signing_key,
143 smb_signature);
144 if(rc)
145 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
146 else
147 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
148
149 return rc;
150
151}
152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153int cifs_verify_signature(struct smb_hdr * cifs_pdu, const char * mac_key,
154 __u32 expected_sequence_number)
155{
156 unsigned int rc;
157 char server_response_sig[8];
158 char what_we_think_sig_should_be[20];
159
160 if((cifs_pdu == NULL) || (mac_key == NULL))
161 return -EINVAL;
162
163 if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
164 return 0;
165
166 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
167 struct smb_com_lock_req * pSMB = (struct smb_com_lock_req *)cifs_pdu;
168 if(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
169 return 0;
170 }
171
172 /* BB what if signatures are supposed to be on for session but server does not
173 send one? BB */
174
175 /* Do not need to verify session setups with signature "BSRSPYL " */
176 if(memcmp(cifs_pdu->Signature.SecuritySignature,"BSRSPYL ",8)==0)
177 cFYI(1,("dummy signature received for smb command 0x%x",cifs_pdu->Command));
178
179 /* save off the origiginal signature so we can modify the smb and check
180 its signature against what the server sent */
181 memcpy(server_response_sig,cifs_pdu->Signature.SecuritySignature,8);
182
183 cifs_pdu->Signature.Sequence.SequenceNumber = cpu_to_le32(expected_sequence_number);
184 cifs_pdu->Signature.Sequence.Reserved = 0;
185
186 rc = cifs_calculate_signature(cifs_pdu, mac_key,
187 what_we_think_sig_should_be);
188
189 if(rc)
190 return rc;
191
192
193/* cifs_dump_mem("what we think it should be: ",what_we_think_sig_should_be,16); */
194
195 if(memcmp(server_response_sig, what_we_think_sig_should_be, 8))
196 return -EACCES;
197 else
198 return 0;
199
200}
201
202/* We fill in key by putting in 40 byte array which was allocated by caller */
203int cifs_calculate_mac_key(char * key, const char * rn, const char * password)
204{
205 char temp_key[16];
206 if ((key == NULL) || (rn == NULL))
207 return -EINVAL;
208
209 E_md4hash(password, temp_key);
210 mdfour(key,temp_key,16);
Steve French7c7b25b2006-06-01 19:20:10 +0000211 memcpy(key+16,rn, CIFS_SESS_KEY_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 return 0;
213}
214
Steve French1717ffc2006-06-08 05:41:32 +0000215int CalcNTLMv2_partial_mac_key(struct cifsSesInfo * ses,
216 const struct nls_table * nls_info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217{
218 char temp_hash[16];
219 struct HMACMD5Context ctx;
220 char * ucase_buf;
Steve Frenche89dc922005-11-11 15:18:19 -0800221 __le16 * unicode_buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 unsigned int i,user_name_len,dom_name_len;
223
224 if(ses == NULL)
225 return -EINVAL;
226
227 E_md4hash(ses->password, temp_hash);
228
229 hmac_md5_init_limK_to_64(temp_hash, 16, &ctx);
230 user_name_len = strlen(ses->userName);
231 if(user_name_len > MAX_USERNAME_SIZE)
232 return -EINVAL;
Steve French39798772006-05-31 22:40:51 +0000233 if(ses->domainName == NULL)
234 return -EINVAL; /* BB should we use CIFS_LINUX_DOM */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 dom_name_len = strlen(ses->domainName);
236 if(dom_name_len > MAX_USERNAME_SIZE)
237 return -EINVAL;
238
239 ucase_buf = kmalloc((MAX_USERNAME_SIZE+1), GFP_KERNEL);
240 if(ucase_buf == NULL)
241 return -ENOMEM;
242 unicode_buf = kmalloc((MAX_USERNAME_SIZE+1)*4, GFP_KERNEL);
243 if(unicode_buf == NULL) {
244 kfree(ucase_buf);
245 return -ENOMEM;
246 }
247
248 for(i=0;i<user_name_len;i++)
249 ucase_buf[i] = nls_info->charset2upper[(int)ses->userName[i]];
250 ucase_buf[i] = 0;
251 user_name_len = cifs_strtoUCS(unicode_buf, ucase_buf, MAX_USERNAME_SIZE*2, nls_info);
252 unicode_buf[user_name_len] = 0;
253 user_name_len++;
254
255 for(i=0;i<dom_name_len;i++)
256 ucase_buf[i] = nls_info->charset2upper[(int)ses->domainName[i]];
257 ucase_buf[i] = 0;
258 dom_name_len = cifs_strtoUCS(unicode_buf+user_name_len, ucase_buf, MAX_USERNAME_SIZE*2, nls_info);
259
260 unicode_buf[user_name_len + dom_name_len] = 0;
261 hmac_md5_update((const unsigned char *) unicode_buf,
262 (user_name_len+dom_name_len)*2,&ctx);
263
Steve Frenchad009ac2005-04-28 22:41:05 -0700264 hmac_md5_final(ses->server->mac_signing_key,&ctx);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 kfree(ucase_buf);
266 kfree(unicode_buf);
267 return 0;
268}
Steve French7c7b25b2006-06-01 19:20:10 +0000269
270#ifdef CONFIG_CIFS_WEAK_PW_HASH
271void calc_lanman_hash(struct cifsSesInfo * ses, char * lnm_session_key)
272{
273 int i;
274 char password_with_pad[CIFS_ENCPWD_SIZE];
275
Steve Frenchbdc4bf6e2006-06-02 22:57:13 +0000276 if(ses->server == NULL)
277 return;
278
Steve French7c7b25b2006-06-01 19:20:10 +0000279 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
Steve French66abda52006-08-11 16:52:09 +0000280 if(ses->password)
281 strncpy(password_with_pad, ses->password, CIFS_ENCPWD_SIZE);
Steve French7c7b25b2006-06-01 19:20:10 +0000282
Steve Frenchbdc4bf6e2006-06-02 22:57:13 +0000283 if((ses->server->secMode & SECMODE_PW_ENCRYPT) == 0)
284 if(extended_security & CIFSSEC_MAY_PLNTXT) {
285 memcpy(lnm_session_key, password_with_pad, CIFS_ENCPWD_SIZE);
286 return;
287 }
288
Steve French7c7b25b2006-06-01 19:20:10 +0000289 /* calculate old style session key */
290 /* calling toupper is less broken than repeatedly
291 calling nls_toupper would be since that will never
292 work for UTF8, but neither handles multibyte code pages
293 but the only alternative would be converting to UCS-16 (Unicode)
294 (using a routine something like UniStrupr) then
295 uppercasing and then converting back from Unicode - which
296 would only worth doing it if we knew it were utf8. Basically
297 utf8 and other multibyte codepages each need their own strupper
298 function since a byte at a time will ont work. */
299
300 for(i = 0; i < CIFS_ENCPWD_SIZE; i++) {
301 password_with_pad[i] = toupper(password_with_pad[i]);
302 }
303
304 SMBencrypt(password_with_pad, ses->server->cryptKey, lnm_session_key);
305 /* clear password before we return/free memory */
306 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
307}
308#endif /* CIFS_WEAK_PW_HASH */
309
Steve French1717ffc2006-06-08 05:41:32 +0000310static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
311 const struct nls_table * nls_cp)
Steve Frencha8ee0342006-06-05 23:34:19 +0000312{
313 int rc = 0;
314 int len;
315 char nt_hash[16];
316 struct HMACMD5Context * pctxt;
Steve French1717ffc2006-06-08 05:41:32 +0000317 wchar_t * user;
318 wchar_t * domain;
Steve Frencha8ee0342006-06-05 23:34:19 +0000319
320 pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL);
321
322 if(pctxt == NULL)
323 return -ENOMEM;
324
325 /* calculate md4 hash of password */
326 E_md4hash(ses->password, nt_hash);
327
Steve French1717ffc2006-06-08 05:41:32 +0000328 /* convert Domainname to unicode and uppercase */
Steve Frencha8ee0342006-06-05 23:34:19 +0000329 hmac_md5_init_limK_to_64(nt_hash, 16, pctxt);
330
331 /* convert ses->userName to unicode and uppercase */
Steve French1717ffc2006-06-08 05:41:32 +0000332 len = strlen(ses->userName);
333 user = kmalloc(2 + (len * 2), GFP_KERNEL);
334 if(user == NULL)
335 goto calc_exit_2;
336 len = cifs_strtoUCS(user, ses->userName, len, nls_cp);
337 UniStrupr(user);
338 hmac_md5_update((char *)user, 2*len, pctxt);
Steve Frencha8ee0342006-06-05 23:34:19 +0000339
340 /* convert ses->domainName to unicode and uppercase */
Steve French1717ffc2006-06-08 05:41:32 +0000341 if(ses->domainName) {
342 len = strlen(ses->domainName);
Steve Frencha8ee0342006-06-05 23:34:19 +0000343
Steve French1717ffc2006-06-08 05:41:32 +0000344 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
345 if(domain == NULL)
346 goto calc_exit_1;
347 len = cifs_strtoUCS(domain, ses->domainName, len, nls_cp);
348 UniStrupr(domain);
Steve Frencha8ee0342006-06-05 23:34:19 +0000349
Steve French1717ffc2006-06-08 05:41:32 +0000350 hmac_md5_update((char *)domain, 2*len, pctxt);
351
352 kfree(domain);
353 }
354calc_exit_1:
355 kfree(user);
356calc_exit_2:
357 /* BB FIXME what about bytes 24 through 40 of the signing key?
358 compare with the NTLM example */
359 hmac_md5_final(ses->server->mac_signing_key, pctxt);
Steve Frencha8ee0342006-06-05 23:34:19 +0000360
361 return rc;
362}
363
Steve French1717ffc2006-06-08 05:41:32 +0000364void setup_ntlmv2_rsp(struct cifsSesInfo * ses, char * resp_buf,
365 const struct nls_table * nls_cp)
Steve French6d027cf2006-06-05 16:26:05 +0000366{
Steve Frencha8ee0342006-06-05 23:34:19 +0000367 int rc;
Steve French6d027cf2006-06-05 16:26:05 +0000368 struct ntlmv2_resp * buf = (struct ntlmv2_resp *)resp_buf;
369
370 buf->blob_signature = cpu_to_le32(0x00000101);
371 buf->reserved = 0;
372 buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
Steve French1717ffc2006-06-08 05:41:32 +0000373 get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
Steve French6d027cf2006-06-05 16:26:05 +0000374 buf->reserved2 = 0;
375 buf->names[0].type = 0;
376 buf->names[0].length = 0;
Steve Frencha8ee0342006-06-05 23:34:19 +0000377
Steve French6d027cf2006-06-05 16:26:05 +0000378 /* calculate buf->ntlmv2_hash */
Steve French1717ffc2006-06-08 05:41:32 +0000379 rc = calc_ntlmv2_hash(ses, nls_cp);
Steve Frencha8ee0342006-06-05 23:34:19 +0000380 if(rc)
381 cERROR(1,("could not get v2 hash rc %d",rc));
Steve French1717ffc2006-06-08 05:41:32 +0000382 CalcNTLMv2_response(ses, resp_buf);
Steve French6d027cf2006-06-05 16:26:05 +0000383}
384
Steve French1717ffc2006-06-08 05:41:32 +0000385void CalcNTLMv2_response(const struct cifsSesInfo * ses, char * v2_session_response)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386{
387 struct HMACMD5Context context;
Steve French1717ffc2006-06-08 05:41:32 +0000388 /* rest of v2 struct already generated */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 memcpy(v2_session_response + 8, ses->server->cryptKey,8);
Steve Frenchad009ac2005-04-28 22:41:05 -0700390 hmac_md5_init_limK_to_64(ses->server->mac_signing_key, 16, &context);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391
Steve French1717ffc2006-06-08 05:41:32 +0000392 hmac_md5_update(v2_session_response+8,
393 sizeof(struct ntlmv2_resp) - 8, &context);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394
395 hmac_md5_final(v2_session_response,&context);
Steve French1717ffc2006-06-08 05:41:32 +0000396/* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397}