Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6
[sfrench/cifs-2.6.git] / fs / cifs / cifsencrypt.c
1 /*
2  *   fs/cifs/cifsencrypt.c
3  *
4  *   Copyright (C) International Business Machines  Corp., 2005
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 "cifspdu.h"
24 #include "cifsglob.h" 
25 #include "cifs_debug.h"
26 #include "md5.h"
27 #include "cifs_unicode.h"
28 #include "cifsproto.h"
29
30 /* Calculate and return the CIFS signature based on the mac key and the smb pdu */
31 /* the 16 byte signature must be allocated by the caller  */
32 /* Note we only use the 1st eight bytes */
33 /* Note that the smb header signature field on input contains the  
34         sequence number before this function is called */
35
36 extern void mdfour(unsigned char *out, unsigned char *in, int n);
37 extern void E_md4hash(const unsigned char *passwd, unsigned char *p16);
38         
39 static int cifs_calculate_signature(const struct smb_hdr * cifs_pdu, const char * key, char * signature)
40 {
41         struct  MD5Context context;
42
43         if((cifs_pdu == NULL) || (signature == NULL))
44                 return -EINVAL;
45
46         MD5Init(&context);
47         MD5Update(&context,key,CIFS_SESSION_KEY_SIZE+16);
48         MD5Update(&context,cifs_pdu->Protocol,cifs_pdu->smb_buf_length);
49         MD5Final(signature,&context);
50         return 0;
51 }
52
53 int cifs_sign_smb(struct smb_hdr * cifs_pdu, struct TCP_Server_Info * server,
54         __u32 * pexpected_response_sequence_number)
55 {
56         int rc = 0;
57         char smb_signature[20];
58
59         /* BB remember to initialize sequence number elsewhere and initialize mac_signing key elsewhere BB */
60         /* BB remember to add code to save expected sequence number in midQ entry BB */
61
62         if((cifs_pdu == NULL) || (server == NULL))
63                 return -EINVAL;
64
65         if((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0) 
66                 return rc;
67
68         spin_lock(&GlobalMid_Lock);
69         cifs_pdu->Signature.Sequence.SequenceNumber = cpu_to_le32(server->sequence_number);
70         cifs_pdu->Signature.Sequence.Reserved = 0;
71         
72         *pexpected_response_sequence_number = server->sequence_number++;
73         server->sequence_number++;
74         spin_unlock(&GlobalMid_Lock);
75
76         rc = cifs_calculate_signature(cifs_pdu, server->mac_signing_key,smb_signature);
77         if(rc)
78                 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
79         else
80                 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
81
82         return rc;
83 }
84
85 static int cifs_calc_signature2(const struct kvec * iov, int n_vec,
86                                 const char * key, char * signature)
87 {
88         struct  MD5Context context;
89
90         if((iov == NULL) || (signature == NULL))
91                 return -EINVAL;
92
93         MD5Init(&context);
94         MD5Update(&context,key,CIFS_SESSION_KEY_SIZE+16);
95
96 /*        MD5Update(&context,cifs_pdu->Protocol,cifs_pdu->smb_buf_length); */ /* BB FIXME BB */
97
98         MD5Final(signature,&context);
99
100         return -EOPNOTSUPP;
101 /*        return 0; */
102 }
103
104
105 int cifs_sign_smb2(struct kvec * iov, int n_vec, struct TCP_Server_Info *server,
106                    __u32 * pexpected_response_sequence_number)
107 {
108         int rc = 0;
109         char smb_signature[20];
110         struct smb_hdr * cifs_pdu = iov[0].iov_base;
111
112         if((cifs_pdu == NULL) || (server == NULL))
113                 return -EINVAL;
114
115         if((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
116                 return rc;
117
118         spin_lock(&GlobalMid_Lock);
119         cifs_pdu->Signature.Sequence.SequenceNumber = 
120                                 cpu_to_le32(server->sequence_number);
121         cifs_pdu->Signature.Sequence.Reserved = 0;
122
123         *pexpected_response_sequence_number = server->sequence_number++;
124         server->sequence_number++;
125         spin_unlock(&GlobalMid_Lock);
126
127         rc = cifs_calc_signature2(iov, n_vec, server->mac_signing_key,
128                                       smb_signature);
129         if(rc)
130                 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
131         else
132                 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
133
134         return rc;
135
136 }
137
138 int cifs_verify_signature(struct smb_hdr * cifs_pdu, const char * mac_key,
139         __u32 expected_sequence_number)
140 {
141         unsigned int rc;
142         char server_response_sig[8];
143         char what_we_think_sig_should_be[20];
144
145         if((cifs_pdu == NULL) || (mac_key == NULL))
146                 return -EINVAL;
147
148         if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
149                 return 0;
150
151         if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
152                 struct smb_com_lock_req * pSMB = (struct smb_com_lock_req *)cifs_pdu;
153             if(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
154                         return 0;
155         }
156
157         /* BB what if signatures are supposed to be on for session but server does not
158                 send one? BB */
159         
160         /* Do not need to verify session setups with signature "BSRSPYL "  */
161         if(memcmp(cifs_pdu->Signature.SecuritySignature,"BSRSPYL ",8)==0)
162                 cFYI(1,("dummy signature received for smb command 0x%x",cifs_pdu->Command));
163
164         /* save off the origiginal signature so we can modify the smb and check
165                 its signature against what the server sent */
166         memcpy(server_response_sig,cifs_pdu->Signature.SecuritySignature,8);
167
168         cifs_pdu->Signature.Sequence.SequenceNumber = cpu_to_le32(expected_sequence_number);
169         cifs_pdu->Signature.Sequence.Reserved = 0;
170
171         rc = cifs_calculate_signature(cifs_pdu, mac_key,
172                 what_we_think_sig_should_be);
173
174         if(rc)
175                 return rc;
176
177         
178 /*      cifs_dump_mem("what we think it should be: ",what_we_think_sig_should_be,16); */
179
180         if(memcmp(server_response_sig, what_we_think_sig_should_be, 8))
181                 return -EACCES;
182         else
183                 return 0;
184
185 }
186
187 /* We fill in key by putting in 40 byte array which was allocated by caller */
188 int cifs_calculate_mac_key(char * key, const char * rn, const char * password)
189 {
190         char temp_key[16];
191         if ((key == NULL) || (rn == NULL))
192                 return -EINVAL;
193
194         E_md4hash(password, temp_key);
195         mdfour(key,temp_key,16);
196         memcpy(key+16,rn, CIFS_SESSION_KEY_SIZE);
197         return 0;
198 }
199
200 int CalcNTLMv2_partial_mac_key(struct cifsSesInfo * ses, struct nls_table * nls_info)
201 {
202         char temp_hash[16];
203         struct HMACMD5Context ctx;
204         char * ucase_buf;
205         __le16 * unicode_buf;
206         unsigned int i,user_name_len,dom_name_len;
207
208         if(ses == NULL)
209                 return -EINVAL;
210
211         E_md4hash(ses->password, temp_hash);
212
213         hmac_md5_init_limK_to_64(temp_hash, 16, &ctx);
214         user_name_len = strlen(ses->userName);
215         if(user_name_len > MAX_USERNAME_SIZE)
216                 return -EINVAL;
217         dom_name_len = strlen(ses->domainName);
218         if(dom_name_len > MAX_USERNAME_SIZE)
219                 return -EINVAL;
220   
221         ucase_buf = kmalloc((MAX_USERNAME_SIZE+1), GFP_KERNEL);
222         if(ucase_buf == NULL)
223                 return -ENOMEM;
224         unicode_buf = kmalloc((MAX_USERNAME_SIZE+1)*4, GFP_KERNEL);
225         if(unicode_buf == NULL) {
226                 kfree(ucase_buf);
227                 return -ENOMEM;
228         }
229    
230         for(i=0;i<user_name_len;i++)
231                 ucase_buf[i] = nls_info->charset2upper[(int)ses->userName[i]];
232         ucase_buf[i] = 0;
233         user_name_len = cifs_strtoUCS(unicode_buf, ucase_buf, MAX_USERNAME_SIZE*2, nls_info);
234         unicode_buf[user_name_len] = 0;
235         user_name_len++;
236
237         for(i=0;i<dom_name_len;i++)
238                 ucase_buf[i] = nls_info->charset2upper[(int)ses->domainName[i]];
239         ucase_buf[i] = 0;
240         dom_name_len = cifs_strtoUCS(unicode_buf+user_name_len, ucase_buf, MAX_USERNAME_SIZE*2, nls_info);
241
242         unicode_buf[user_name_len + dom_name_len] = 0;
243         hmac_md5_update((const unsigned char *) unicode_buf,
244                 (user_name_len+dom_name_len)*2,&ctx);
245
246         hmac_md5_final(ses->server->mac_signing_key,&ctx);
247         kfree(ucase_buf);
248         kfree(unicode_buf);
249         return 0;
250 }
251 void CalcNTLMv2_response(const struct cifsSesInfo * ses,char * v2_session_response)
252 {
253         struct HMACMD5Context context;
254         memcpy(v2_session_response + 8, ses->server->cryptKey,8);
255         /* gen_blob(v2_session_response + 16); */
256         hmac_md5_init_limK_to_64(ses->server->mac_signing_key, 16, &context);
257
258         hmac_md5_update(ses->server->cryptKey,8,&context);
259 /*      hmac_md5_update(v2_session_response+16)client thing,8,&context); */ /* BB fix */
260
261         hmac_md5_final(v2_session_response,&context);
262 }