Root/
1 | /* |
2 | * fs/cifs/cifsencrypt.c |
3 | * |
4 | * Copyright (C) International Business Machines Corp., 2005,2006 |
5 | * 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 <linux/slab.h> |
24 | #include "cifspdu.h" |
25 | #include "cifsglob.h" |
26 | #include "cifs_debug.h" |
27 | #include "md5.h" |
28 | #include "cifs_unicode.h" |
29 | #include "cifsproto.h" |
30 | #include <linux/ctype.h> |
31 | #include <linux/random.h> |
32 | |
33 | /* Calculate and return the CIFS signature based on the mac key and SMB PDU */ |
34 | /* the 16 byte signature must be allocated by the caller */ |
35 | /* Note we only use the 1st eight bytes */ |
36 | /* Note that the smb header signature field on input contains the |
37 | sequence number before this function is called */ |
38 | |
39 | extern void mdfour(unsigned char *out, unsigned char *in, int n); |
40 | extern void E_md4hash(const unsigned char *passwd, unsigned char *p16); |
41 | extern void SMBencrypt(unsigned char *passwd, const unsigned char *c8, |
42 | unsigned char *p24); |
43 | |
44 | static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu, |
45 | const struct mac_key *key, char *signature) |
46 | { |
47 | struct MD5Context context; |
48 | |
49 | if ((cifs_pdu == NULL) || (signature == NULL) || (key == NULL)) |
50 | return -EINVAL; |
51 | |
52 | cifs_MD5_init(&context); |
53 | cifs_MD5_update(&context, (char *)&key->data, key->len); |
54 | cifs_MD5_update(&context, cifs_pdu->Protocol, cifs_pdu->smb_buf_length); |
55 | |
56 | cifs_MD5_final(signature, &context); |
57 | return 0; |
58 | } |
59 | |
60 | int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server, |
61 | __u32 *pexpected_response_sequence_number) |
62 | { |
63 | int rc = 0; |
64 | char smb_signature[20]; |
65 | |
66 | if ((cifs_pdu == NULL) || (server == NULL)) |
67 | return -EINVAL; |
68 | |
69 | if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0) |
70 | return rc; |
71 | |
72 | spin_lock(&GlobalMid_Lock); |
73 | cifs_pdu->Signature.Sequence.SequenceNumber = |
74 | cpu_to_le32(server->sequence_number); |
75 | cifs_pdu->Signature.Sequence.Reserved = 0; |
76 | |
77 | *pexpected_response_sequence_number = server->sequence_number++; |
78 | server->sequence_number++; |
79 | spin_unlock(&GlobalMid_Lock); |
80 | |
81 | rc = cifs_calculate_signature(cifs_pdu, &server->mac_signing_key, |
82 | smb_signature); |
83 | if (rc) |
84 | memset(cifs_pdu->Signature.SecuritySignature, 0, 8); |
85 | else |
86 | memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8); |
87 | |
88 | return rc; |
89 | } |
90 | |
91 | static int cifs_calc_signature2(const struct kvec *iov, int n_vec, |
92 | const struct mac_key *key, char *signature) |
93 | { |
94 | struct MD5Context context; |
95 | int i; |
96 | |
97 | if ((iov == NULL) || (signature == NULL) || (key == NULL)) |
98 | return -EINVAL; |
99 | |
100 | cifs_MD5_init(&context); |
101 | cifs_MD5_update(&context, (char *)&key->data, key->len); |
102 | for (i = 0; i < n_vec; i++) { |
103 | if (iov[i].iov_len == 0) |
104 | continue; |
105 | if (iov[i].iov_base == NULL) { |
106 | cERROR(1, ("null iovec entry")); |
107 | return -EIO; |
108 | } |
109 | /* The first entry includes a length field (which does not get |
110 | signed that occupies the first 4 bytes before the header */ |
111 | if (i == 0) { |
112 | if (iov[0].iov_len <= 8) /* cmd field at offset 9 */ |
113 | break; /* nothing to sign or corrupt header */ |
114 | cifs_MD5_update(&context, iov[0].iov_base+4, |
115 | iov[0].iov_len-4); |
116 | } else |
117 | cifs_MD5_update(&context, iov[i].iov_base, iov[i].iov_len); |
118 | } |
119 | |
120 | cifs_MD5_final(signature, &context); |
121 | |
122 | return 0; |
123 | } |
124 | |
125 | |
126 | int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server, |
127 | __u32 *pexpected_response_sequence_number) |
128 | { |
129 | int rc = 0; |
130 | char smb_signature[20]; |
131 | struct smb_hdr *cifs_pdu = iov[0].iov_base; |
132 | |
133 | if ((cifs_pdu == NULL) || (server == NULL)) |
134 | return -EINVAL; |
135 | |
136 | if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0) |
137 | return rc; |
138 | |
139 | spin_lock(&GlobalMid_Lock); |
140 | cifs_pdu->Signature.Sequence.SequenceNumber = |
141 | cpu_to_le32(server->sequence_number); |
142 | cifs_pdu->Signature.Sequence.Reserved = 0; |
143 | |
144 | *pexpected_response_sequence_number = server->sequence_number++; |
145 | server->sequence_number++; |
146 | spin_unlock(&GlobalMid_Lock); |
147 | |
148 | rc = cifs_calc_signature2(iov, n_vec, &server->mac_signing_key, |
149 | smb_signature); |
150 | if (rc) |
151 | memset(cifs_pdu->Signature.SecuritySignature, 0, 8); |
152 | else |
153 | memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8); |
154 | |
155 | return rc; |
156 | } |
157 | |
158 | int cifs_verify_signature(struct smb_hdr *cifs_pdu, |
159 | const struct mac_key *mac_key, |
160 | __u32 expected_sequence_number) |
161 | { |
162 | unsigned int rc; |
163 | char server_response_sig[8]; |
164 | char what_we_think_sig_should_be[20]; |
165 | |
166 | if ((cifs_pdu == NULL) || (mac_key == NULL)) |
167 | return -EINVAL; |
168 | |
169 | if (cifs_pdu->Command == SMB_COM_NEGOTIATE) |
170 | return 0; |
171 | |
172 | if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) { |
173 | struct smb_com_lock_req *pSMB = |
174 | (struct smb_com_lock_req *)cifs_pdu; |
175 | if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE) |
176 | return 0; |
177 | } |
178 | |
179 | /* BB what if signatures are supposed to be on for session but |
180 | server does not send one? BB */ |
181 | |
182 | /* Do not need to verify session setups with signature "BSRSPYL " */ |
183 | if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0) |
184 | cFYI(1, ("dummy signature received for smb command 0x%x", |
185 | cifs_pdu->Command)); |
186 | |
187 | /* save off the origiginal signature so we can modify the smb and check |
188 | its signature against what the server sent */ |
189 | memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8); |
190 | |
191 | cifs_pdu->Signature.Sequence.SequenceNumber = |
192 | cpu_to_le32(expected_sequence_number); |
193 | cifs_pdu->Signature.Sequence.Reserved = 0; |
194 | |
195 | rc = cifs_calculate_signature(cifs_pdu, mac_key, |
196 | what_we_think_sig_should_be); |
197 | |
198 | if (rc) |
199 | return rc; |
200 | |
201 | /* cifs_dump_mem("what we think it should be: ", |
202 | what_we_think_sig_should_be, 16); */ |
203 | |
204 | if (memcmp(server_response_sig, what_we_think_sig_should_be, 8)) |
205 | return -EACCES; |
206 | else |
207 | return 0; |
208 | |
209 | } |
210 | |
211 | /* We fill in key by putting in 40 byte array which was allocated by caller */ |
212 | int cifs_calculate_mac_key(struct mac_key *key, const char *rn, |
213 | const char *password) |
214 | { |
215 | char temp_key[16]; |
216 | if ((key == NULL) || (rn == NULL)) |
217 | return -EINVAL; |
218 | |
219 | E_md4hash(password, temp_key); |
220 | mdfour(key->data.ntlm, temp_key, 16); |
221 | memcpy(key->data.ntlm+16, rn, CIFS_SESS_KEY_SIZE); |
222 | key->len = 40; |
223 | return 0; |
224 | } |
225 | |
226 | int CalcNTLMv2_partial_mac_key(struct cifsSesInfo *ses, |
227 | const struct nls_table *nls_info) |
228 | { |
229 | char temp_hash[16]; |
230 | struct HMACMD5Context ctx; |
231 | char *ucase_buf; |
232 | __le16 *unicode_buf; |
233 | unsigned int i, user_name_len, dom_name_len; |
234 | |
235 | if (ses == NULL) |
236 | return -EINVAL; |
237 | |
238 | E_md4hash(ses->password, temp_hash); |
239 | |
240 | hmac_md5_init_limK_to_64(temp_hash, 16, &ctx); |
241 | user_name_len = strlen(ses->userName); |
242 | if (user_name_len > MAX_USERNAME_SIZE) |
243 | return -EINVAL; |
244 | if (ses->domainName == NULL) |
245 | return -EINVAL; /* BB should we use CIFS_LINUX_DOM */ |
246 | dom_name_len = strlen(ses->domainName); |
247 | if (dom_name_len > MAX_USERNAME_SIZE) |
248 | return -EINVAL; |
249 | |
250 | ucase_buf = kmalloc((MAX_USERNAME_SIZE+1), GFP_KERNEL); |
251 | if (ucase_buf == NULL) |
252 | return -ENOMEM; |
253 | unicode_buf = kmalloc((MAX_USERNAME_SIZE+1)*4, GFP_KERNEL); |
254 | if (unicode_buf == NULL) { |
255 | kfree(ucase_buf); |
256 | return -ENOMEM; |
257 | } |
258 | |
259 | for (i = 0; i < user_name_len; i++) |
260 | ucase_buf[i] = nls_info->charset2upper[(int)ses->userName[i]]; |
261 | ucase_buf[i] = 0; |
262 | user_name_len = cifs_strtoUCS(unicode_buf, ucase_buf, |
263 | MAX_USERNAME_SIZE*2, nls_info); |
264 | unicode_buf[user_name_len] = 0; |
265 | user_name_len++; |
266 | |
267 | for (i = 0; i < dom_name_len; i++) |
268 | ucase_buf[i] = nls_info->charset2upper[(int)ses->domainName[i]]; |
269 | ucase_buf[i] = 0; |
270 | dom_name_len = cifs_strtoUCS(unicode_buf+user_name_len, ucase_buf, |
271 | MAX_USERNAME_SIZE*2, nls_info); |
272 | |
273 | unicode_buf[user_name_len + dom_name_len] = 0; |
274 | hmac_md5_update((const unsigned char *) unicode_buf, |
275 | (user_name_len+dom_name_len)*2, &ctx); |
276 | |
277 | hmac_md5_final(ses->server->ntlmv2_hash, &ctx); |
278 | kfree(ucase_buf); |
279 | kfree(unicode_buf); |
280 | return 0; |
281 | } |
282 | |
283 | #ifdef CONFIG_CIFS_WEAK_PW_HASH |
284 | void calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt, |
285 | char *lnm_session_key) |
286 | { |
287 | int i; |
288 | char password_with_pad[CIFS_ENCPWD_SIZE]; |
289 | |
290 | memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); |
291 | if (password) |
292 | strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE); |
293 | |
294 | if (!encrypt && extended_security & CIFSSEC_MAY_PLNTXT) { |
295 | memset(lnm_session_key, 0, CIFS_SESS_KEY_SIZE); |
296 | memcpy(lnm_session_key, password_with_pad, |
297 | CIFS_ENCPWD_SIZE); |
298 | return; |
299 | } |
300 | |
301 | /* calculate old style session key */ |
302 | /* calling toupper is less broken than repeatedly |
303 | calling nls_toupper would be since that will never |
304 | work for UTF8, but neither handles multibyte code pages |
305 | but the only alternative would be converting to UCS-16 (Unicode) |
306 | (using a routine something like UniStrupr) then |
307 | uppercasing and then converting back from Unicode - which |
308 | would only worth doing it if we knew it were utf8. Basically |
309 | utf8 and other multibyte codepages each need their own strupper |
310 | function since a byte at a time will ont work. */ |
311 | |
312 | for (i = 0; i < CIFS_ENCPWD_SIZE; i++) |
313 | password_with_pad[i] = toupper(password_with_pad[i]); |
314 | |
315 | SMBencrypt(password_with_pad, cryptkey, lnm_session_key); |
316 | |
317 | /* clear password before we return/free memory */ |
318 | memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); |
319 | } |
320 | #endif /* CIFS_WEAK_PW_HASH */ |
321 | |
322 | static int calc_ntlmv2_hash(struct cifsSesInfo *ses, |
323 | const struct nls_table *nls_cp) |
324 | { |
325 | int rc = 0; |
326 | int len; |
327 | char nt_hash[16]; |
328 | struct HMACMD5Context *pctxt; |
329 | wchar_t *user; |
330 | wchar_t *domain; |
331 | |
332 | pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL); |
333 | |
334 | if (pctxt == NULL) |
335 | return -ENOMEM; |
336 | |
337 | /* calculate md4 hash of password */ |
338 | E_md4hash(ses->password, nt_hash); |
339 | |
340 | /* convert Domainname to unicode and uppercase */ |
341 | hmac_md5_init_limK_to_64(nt_hash, 16, pctxt); |
342 | |
343 | /* convert ses->userName to unicode and uppercase */ |
344 | len = strlen(ses->userName); |
345 | user = kmalloc(2 + (len * 2), GFP_KERNEL); |
346 | if (user == NULL) |
347 | goto calc_exit_2; |
348 | len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp); |
349 | UniStrupr(user); |
350 | hmac_md5_update((char *)user, 2*len, pctxt); |
351 | |
352 | /* convert ses->domainName to unicode and uppercase */ |
353 | if (ses->domainName) { |
354 | len = strlen(ses->domainName); |
355 | |
356 | domain = kmalloc(2 + (len * 2), GFP_KERNEL); |
357 | if (domain == NULL) |
358 | goto calc_exit_1; |
359 | len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len, |
360 | nls_cp); |
361 | /* the following line was removed since it didn't work well |
362 | with lower cased domain name that passed as an option. |
363 | Maybe converting the domain name earlier makes sense */ |
364 | /* UniStrupr(domain); */ |
365 | |
366 | hmac_md5_update((char *)domain, 2*len, pctxt); |
367 | |
368 | kfree(domain); |
369 | } |
370 | calc_exit_1: |
371 | kfree(user); |
372 | calc_exit_2: |
373 | /* BB FIXME what about bytes 24 through 40 of the signing key? |
374 | compare with the NTLM example */ |
375 | hmac_md5_final(ses->server->ntlmv2_hash, pctxt); |
376 | |
377 | kfree(pctxt); |
378 | return rc; |
379 | } |
380 | |
381 | void setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf, |
382 | const struct nls_table *nls_cp) |
383 | { |
384 | int rc; |
385 | struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf; |
386 | struct HMACMD5Context context; |
387 | |
388 | buf->blob_signature = cpu_to_le32(0x00000101); |
389 | buf->reserved = 0; |
390 | buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME)); |
391 | get_random_bytes(&buf->client_chal, sizeof(buf->client_chal)); |
392 | buf->reserved2 = 0; |
393 | buf->names[0].type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE); |
394 | buf->names[0].length = 0; |
395 | buf->names[1].type = 0; |
396 | buf->names[1].length = 0; |
397 | |
398 | /* calculate buf->ntlmv2_hash */ |
399 | rc = calc_ntlmv2_hash(ses, nls_cp); |
400 | if (rc) |
401 | cERROR(1, ("could not get v2 hash rc %d", rc)); |
402 | CalcNTLMv2_response(ses, resp_buf); |
403 | |
404 | /* now calculate the MAC key for NTLMv2 */ |
405 | hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context); |
406 | hmac_md5_update(resp_buf, 16, &context); |
407 | hmac_md5_final(ses->server->mac_signing_key.data.ntlmv2.key, &context); |
408 | |
409 | memcpy(&ses->server->mac_signing_key.data.ntlmv2.resp, resp_buf, |
410 | sizeof(struct ntlmv2_resp)); |
411 | ses->server->mac_signing_key.len = 16 + sizeof(struct ntlmv2_resp); |
412 | } |
413 | |
414 | void CalcNTLMv2_response(const struct cifsSesInfo *ses, |
415 | char *v2_session_response) |
416 | { |
417 | struct HMACMD5Context context; |
418 | /* rest of v2 struct already generated */ |
419 | memcpy(v2_session_response + 8, ses->server->cryptKey, 8); |
420 | hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context); |
421 | |
422 | hmac_md5_update(v2_session_response+8, |
423 | sizeof(struct ntlmv2_resp) - 8, &context); |
424 | |
425 | hmac_md5_final(v2_session_response, &context); |
426 | /* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */ |
427 | } |
428 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9