2 * fs/cifs/cifsencrypt.c
4 * Copyright (C) International Business Machines Corp., 2005,2006
5 * Author(s): Steve French (sfrench@us.ibm.com)
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.
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.
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
25 #include "cifs_debug.h"
27 #include "cifs_unicode.h"
28 #include "cifsproto.h"
29 #include <linux/ctype.h>
30 #include <linux/random.h>
32 /* Calculate and return the CIFS signature based on the mac key and 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 */
38 extern void mdfour(unsigned char *out, unsigned char *in, int n);
39 extern void E_md4hash(const unsigned char *passwd, unsigned char *p16);
40 extern void SMBencrypt(unsigned char *passwd, unsigned char *c8,
43 static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
44 const struct mac_key *key, char *signature)
46 struct MD5Context context;
48 if ((cifs_pdu == NULL) || (signature == NULL) || (key == NULL))
52 MD5Update(&context, (char *)&key->data, key->len);
53 MD5Update(&context, cifs_pdu->Protocol, cifs_pdu->smb_buf_length);
55 MD5Final(signature, &context);
59 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
60 __u32 *pexpected_response_sequence_number)
63 char smb_signature[20];
65 if ((cifs_pdu == NULL) || (server == NULL))
68 if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
71 spin_lock(&GlobalMid_Lock);
72 cifs_pdu->Signature.Sequence.SequenceNumber =
73 cpu_to_le32(server->sequence_number);
74 cifs_pdu->Signature.Sequence.Reserved = 0;
76 *pexpected_response_sequence_number = server->sequence_number++;
77 server->sequence_number++;
78 spin_unlock(&GlobalMid_Lock);
80 rc = cifs_calculate_signature(cifs_pdu, &server->mac_signing_key,
83 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
85 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
90 static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
91 const struct mac_key *key, char *signature)
93 struct MD5Context context;
96 if ((iov == NULL) || (signature == NULL) || (key == NULL))
100 MD5Update(&context, (char *)&key->data, key->len);
101 for (i = 0; i < n_vec; i++) {
102 if (iov[i].iov_base == NULL) {
103 cERROR(1, ("null iovec entry"));
105 } else if (iov[i].iov_len == 0)
106 break; /* bail out if we are sent nothing to sign */
107 /* The first entry includes a length field (which does not get
108 signed that occupies the first 4 bytes before the header */
110 if (iov[0].iov_len <= 8 ) /* cmd field at offset 9 */
111 break; /* nothing to sign or corrupt header */
112 MD5Update(&context,iov[0].iov_base+4, iov[0].iov_len-4);
114 MD5Update(&context, iov[i].iov_base, iov[i].iov_len);
117 MD5Final(signature, &context);
123 int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
124 __u32 * pexpected_response_sequence_number)
127 char smb_signature[20];
128 struct smb_hdr *cifs_pdu = iov[0].iov_base;
130 if ((cifs_pdu == NULL) || (server == NULL))
133 if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
136 spin_lock(&GlobalMid_Lock);
137 cifs_pdu->Signature.Sequence.SequenceNumber =
138 cpu_to_le32(server->sequence_number);
139 cifs_pdu->Signature.Sequence.Reserved = 0;
141 *pexpected_response_sequence_number = server->sequence_number++;
142 server->sequence_number++;
143 spin_unlock(&GlobalMid_Lock);
145 rc = cifs_calc_signature2(iov, n_vec, &server->mac_signing_key,
148 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
150 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
155 int cifs_verify_signature(struct smb_hdr *cifs_pdu,
156 const struct mac_key *mac_key,
157 __u32 expected_sequence_number)
160 char server_response_sig[8];
161 char what_we_think_sig_should_be[20];
163 if ((cifs_pdu == NULL) || (mac_key == NULL))
166 if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
169 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
170 struct smb_com_lock_req *pSMB =
171 (struct smb_com_lock_req *)cifs_pdu;
172 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
176 /* BB what if signatures are supposed to be on for session but
177 server does not send one? BB */
179 /* Do not need to verify session setups with signature "BSRSPYL " */
180 if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
181 cFYI(1, ("dummy signature received for smb command 0x%x",
184 /* save off the origiginal signature so we can modify the smb and check
185 its signature against what the server sent */
186 memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
188 cifs_pdu->Signature.Sequence.SequenceNumber =
189 cpu_to_le32(expected_sequence_number);
190 cifs_pdu->Signature.Sequence.Reserved = 0;
192 rc = cifs_calculate_signature(cifs_pdu, mac_key,
193 what_we_think_sig_should_be);
198 /* cifs_dump_mem("what we think it should be: ",
199 what_we_think_sig_should_be, 16); */
201 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
208 /* We fill in key by putting in 40 byte array which was allocated by caller */
209 int cifs_calculate_mac_key(struct mac_key *key, const char *rn,
210 const char *password)
213 if ((key == NULL) || (rn == NULL))
216 E_md4hash(password, temp_key);
217 mdfour(key->data.ntlm, temp_key, 16);
218 memcpy(key->data.ntlm+16, rn, CIFS_SESS_KEY_SIZE);
223 int CalcNTLMv2_partial_mac_key(struct cifsSesInfo *ses,
224 const struct nls_table *nls_info)
227 struct HMACMD5Context ctx;
230 unsigned int i, user_name_len, dom_name_len;
235 E_md4hash(ses->password, temp_hash);
237 hmac_md5_init_limK_to_64(temp_hash, 16, &ctx);
238 user_name_len = strlen(ses->userName);
239 if (user_name_len > MAX_USERNAME_SIZE)
241 if (ses->domainName == NULL)
242 return -EINVAL; /* BB should we use CIFS_LINUX_DOM */
243 dom_name_len = strlen(ses->domainName);
244 if (dom_name_len > MAX_USERNAME_SIZE)
247 ucase_buf = kmalloc((MAX_USERNAME_SIZE+1), GFP_KERNEL);
248 if (ucase_buf == NULL)
250 unicode_buf = kmalloc((MAX_USERNAME_SIZE+1)*4, GFP_KERNEL);
251 if (unicode_buf == NULL) {
256 for (i = 0; i < user_name_len; i++)
257 ucase_buf[i] = nls_info->charset2upper[(int)ses->userName[i]];
259 user_name_len = cifs_strtoUCS(unicode_buf, ucase_buf,
260 MAX_USERNAME_SIZE*2, nls_info);
261 unicode_buf[user_name_len] = 0;
264 for (i = 0; i < dom_name_len; i++)
265 ucase_buf[i] = nls_info->charset2upper[(int)ses->domainName[i]];
267 dom_name_len = cifs_strtoUCS(unicode_buf+user_name_len, ucase_buf,
268 MAX_USERNAME_SIZE*2, nls_info);
270 unicode_buf[user_name_len + dom_name_len] = 0;
271 hmac_md5_update((const unsigned char *) unicode_buf,
272 (user_name_len+dom_name_len)*2, &ctx);
274 hmac_md5_final(ses->server->ntlmv2_hash, &ctx);
280 #ifdef CONFIG_CIFS_WEAK_PW_HASH
281 void calc_lanman_hash(struct cifsSesInfo *ses, char *lnm_session_key)
284 char password_with_pad[CIFS_ENCPWD_SIZE];
286 if (ses->server == NULL)
289 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
291 strncpy(password_with_pad, ses->password, CIFS_ENCPWD_SIZE);
293 if ((ses->server->secMode & SECMODE_PW_ENCRYPT) == 0)
294 if (extended_security & CIFSSEC_MAY_PLNTXT) {
295 memcpy(lnm_session_key, password_with_pad,
300 /* calculate old style session key */
301 /* calling toupper is less broken than repeatedly
302 calling nls_toupper would be since that will never
303 work for UTF8, but neither handles multibyte code pages
304 but the only alternative would be converting to UCS-16 (Unicode)
305 (using a routine something like UniStrupr) then
306 uppercasing and then converting back from Unicode - which
307 would only worth doing it if we knew it were utf8. Basically
308 utf8 and other multibyte codepages each need their own strupper
309 function since a byte at a time will ont work. */
311 for (i = 0; i < CIFS_ENCPWD_SIZE; i++) {
312 password_with_pad[i] = toupper(password_with_pad[i]);
315 SMBencrypt(password_with_pad, ses->server->cryptKey, lnm_session_key);
316 /* clear password before we return/free memory */
317 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
319 #endif /* CIFS_WEAK_PW_HASH */
321 static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
322 const struct nls_table *nls_cp)
327 struct HMACMD5Context *pctxt;
331 pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL);
336 /* calculate md4 hash of password */
337 E_md4hash(ses->password, nt_hash);
339 /* convert Domainname to unicode and uppercase */
340 hmac_md5_init_limK_to_64(nt_hash, 16, pctxt);
342 /* convert ses->userName to unicode and uppercase */
343 len = strlen(ses->userName);
344 user = kmalloc(2 + (len * 2), GFP_KERNEL);
347 len = cifs_strtoUCS(user, ses->userName, len, nls_cp);
349 hmac_md5_update((char *)user, 2*len, pctxt);
351 /* convert ses->domainName to unicode and uppercase */
352 if (ses->domainName) {
353 len = strlen(ses->domainName);
355 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
358 len = cifs_strtoUCS(domain, ses->domainName, len, nls_cp);
359 /* the following line was removed since it didn't work well
360 with lower cased domain name that passed as an option.
361 Maybe converting the domain name earlier makes sense */
362 /* UniStrupr(domain); */
364 hmac_md5_update((char *)domain, 2*len, pctxt);
371 /* BB FIXME what about bytes 24 through 40 of the signing key?
372 compare with the NTLM example */
373 hmac_md5_final(ses->server->ntlmv2_hash, pctxt);
378 void setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
379 const struct nls_table *nls_cp)
382 struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf;
383 struct HMACMD5Context context;
385 buf->blob_signature = cpu_to_le32(0x00000101);
387 buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
388 get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
390 buf->names[0].type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE);
391 buf->names[0].length = 0;
392 buf->names[1].type = 0;
393 buf->names[1].length = 0;
395 /* calculate buf->ntlmv2_hash */
396 rc = calc_ntlmv2_hash(ses, nls_cp);
398 cERROR(1, ("could not get v2 hash rc %d", rc));
399 CalcNTLMv2_response(ses, resp_buf);
401 /* now calculate the MAC key for NTLMv2 */
402 hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
403 hmac_md5_update(resp_buf, 16, &context);
404 hmac_md5_final(ses->server->mac_signing_key.data.ntlmv2.key, &context);
406 memcpy(&ses->server->mac_signing_key.data.ntlmv2.resp, resp_buf,
407 sizeof(struct ntlmv2_resp));
408 ses->server->mac_signing_key.len = 16 + sizeof(struct ntlmv2_resp);
411 void CalcNTLMv2_response(const struct cifsSesInfo *ses,
412 char *v2_session_response)
414 struct HMACMD5Context context;
415 /* rest of v2 struct already generated */
416 memcpy(v2_session_response + 8, ses->server->cryptKey, 8);
417 hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
419 hmac_md5_update(v2_session_response+8,
420 sizeof(struct ntlmv2_resp) - 8, &context);
422 hmac_md5_final(v2_session_response, &context);
423 /* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */