4 * Copyright (C) International Business Machines Corp., 2002,2011
6 * Author(s): Steve French (sfrench@us.ibm.com)
7 * Pavel Shilovsky (pshilovsky@samba.org) 2012
9 * This library is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as published
11 * by the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
17 * the GNU Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #include <linux/ctype.h>
26 #include "cifsproto.h"
27 #include "smb2proto.h"
28 #include "cifs_debug.h"
29 #include "cifs_unicode.h"
30 #include "smb2status.h"
33 check_smb2_hdr(struct smb2_hdr
*hdr
, __u64 mid
)
36 * Make sure that this really is an SMB, that it is a response,
37 * and that the message ids match.
39 if ((*(__le32
*)hdr
->ProtocolId
== SMB2_PROTO_NUMBER
) &&
40 (mid
== hdr
->MessageId
)) {
41 if (hdr
->Flags
& SMB2_FLAGS_SERVER_TO_REDIR
)
44 /* only one valid case where server sends us request */
45 if (hdr
->Command
== SMB2_OPLOCK_BREAK
)
48 cERROR(1, "Received Request not response");
50 } else { /* bad signature or mid */
51 if (*(__le32
*)hdr
->ProtocolId
!= SMB2_PROTO_NUMBER
)
52 cERROR(1, "Bad protocol string signature header %x",
53 *(unsigned int *) hdr
->ProtocolId
);
54 if (mid
!= hdr
->MessageId
)
55 cERROR(1, "Mids do not match");
57 cERROR(1, "Bad SMB detected. The Mid=%llu", hdr
->MessageId
);
62 * The following table defines the expected "StructureSize" of SMB2 responses
63 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
65 * Note that commands are defined in smb2pdu.h in le16 but the array below is
66 * indexed by command in host byte order
68 static const __le16 smb2_rsp_struct_sizes
[NUMBER_OF_SMB2_COMMANDS
] = {
69 /* SMB2_NEGOTIATE */ __constant_cpu_to_le16(65),
70 /* SMB2_SESSION_SETUP */ __constant_cpu_to_le16(9),
71 /* SMB2_LOGOFF */ __constant_cpu_to_le16(4),
72 /* SMB2_TREE_CONNECT */ __constant_cpu_to_le16(16),
73 /* SMB2_TREE_DISCONNECT */ __constant_cpu_to_le16(4),
74 /* SMB2_CREATE */ __constant_cpu_to_le16(89),
75 /* SMB2_CLOSE */ __constant_cpu_to_le16(60),
76 /* SMB2_FLUSH */ __constant_cpu_to_le16(4),
77 /* SMB2_READ */ __constant_cpu_to_le16(17),
78 /* SMB2_WRITE */ __constant_cpu_to_le16(17),
79 /* SMB2_LOCK */ __constant_cpu_to_le16(4),
80 /* SMB2_IOCTL */ __constant_cpu_to_le16(49),
81 /* BB CHECK this ... not listed in documentation */
82 /* SMB2_CANCEL */ __constant_cpu_to_le16(0),
83 /* SMB2_ECHO */ __constant_cpu_to_le16(4),
84 /* SMB2_QUERY_DIRECTORY */ __constant_cpu_to_le16(9),
85 /* SMB2_CHANGE_NOTIFY */ __constant_cpu_to_le16(9),
86 /* SMB2_QUERY_INFO */ __constant_cpu_to_le16(9),
87 /* SMB2_SET_INFO */ __constant_cpu_to_le16(2),
88 /* BB FIXME can also be 44 for lease break */
89 /* SMB2_OPLOCK_BREAK */ __constant_cpu_to_le16(24)
93 smb2_check_message(char *buf
, unsigned int length
)
95 struct smb2_hdr
*hdr
= (struct smb2_hdr
*)buf
;
96 struct smb2_pdu
*pdu
= (struct smb2_pdu
*)hdr
;
97 __u64 mid
= hdr
->MessageId
;
98 __u32 len
= get_rfc1002_length(buf
);
99 __u32 clc_len
; /* calculated length */
102 /* BB disable following printk later */
103 cFYI(1, "%s length: 0x%x, smb_buf_length: 0x%x", __func__
, length
, len
);
106 * Add function to do table lookup of StructureSize by command
107 * ie Validate the wct via smb2_struct_sizes table above
110 if (length
< 2 + sizeof(struct smb2_hdr
)) {
111 if ((length
>= sizeof(struct smb2_hdr
)) && (hdr
->Status
!= 0)) {
112 pdu
->StructureSize2
= 0;
114 * As with SMB/CIFS, on some error cases servers may
115 * not return wct properly
119 cERROR(1, "Length less than SMB header size");
123 if (len
> CIFSMaxBufSize
+ MAX_SMB2_HDR_SIZE
- 4) {
124 cERROR(1, "SMB length greater than maximum, mid=%lld", mid
);
128 if (check_smb2_hdr(hdr
, mid
))
131 if (hdr
->StructureSize
!= SMB2_HEADER_SIZE
) {
132 cERROR(1, "Illegal structure size %d",
133 le16_to_cpu(hdr
->StructureSize
));
137 command
= le16_to_cpu(hdr
->Command
);
138 if (command
>= NUMBER_OF_SMB2_COMMANDS
) {
139 cERROR(1, "Illegal SMB2 command %d", command
);
143 if (smb2_rsp_struct_sizes
[command
] != pdu
->StructureSize2
) {
144 if (hdr
->Status
== 0 ||
145 pdu
->StructureSize2
!= SMB2_ERROR_STRUCTURE_SIZE2
) {
146 /* error packets have 9 byte structure size */
147 cERROR(1, "Illegal response size %u for command %d",
148 le16_to_cpu(pdu
->StructureSize2
), command
);
153 if (4 + len
!= length
) {
154 cERROR(1, "Total length %u RFC1002 length %u mismatch mid %llu",
155 length
, 4 + len
, mid
);
159 clc_len
= smb2_calc_size(hdr
);
161 if (4 + len
!= clc_len
) {
162 cFYI(1, "Calculated size %u length %u mismatch mid %llu",
163 clc_len
, 4 + len
, mid
);
164 if (clc_len
== 4 + len
+ 1) /* BB FIXME (fix samba) */
165 return 0; /* BB workaround Samba 3 bug SessSetup rsp */
172 * The size of the variable area depends on the offset and length fields
173 * located in different fields for various SMB2 responses. SMB2 responses
174 * with no variable length info, show an offset of zero for the offset field.
176 static const bool has_smb2_data_area
[NUMBER_OF_SMB2_COMMANDS
] = {
177 /* SMB2_NEGOTIATE */ true,
178 /* SMB2_SESSION_SETUP */ true,
179 /* SMB2_LOGOFF */ false,
180 /* SMB2_TREE_CONNECT */ false,
181 /* SMB2_TREE_DISCONNECT */ false,
182 /* SMB2_CREATE */ true,
183 /* SMB2_CLOSE */ false,
184 /* SMB2_FLUSH */ false,
185 /* SMB2_READ */ true,
186 /* SMB2_WRITE */ false,
187 /* SMB2_LOCK */ false,
188 /* SMB2_IOCTL */ true,
189 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
190 /* SMB2_ECHO */ false,
191 /* SMB2_QUERY_DIRECTORY */ true,
192 /* SMB2_CHANGE_NOTIFY */ true,
193 /* SMB2_QUERY_INFO */ true,
194 /* SMB2_SET_INFO */ false,
195 /* SMB2_OPLOCK_BREAK */ false
199 * Returns the pointer to the beginning of the data area. Length of the data
200 * area and the offset to it (from the beginning of the smb are also returned.
203 smb2_get_data_area_len(int *off
, int *len
, struct smb2_hdr
*hdr
)
208 /* error responses do not have data area */
209 if (hdr
->Status
&& hdr
->Status
!= STATUS_MORE_PROCESSING_REQUIRED
&&
210 (((struct smb2_err_rsp
*)hdr
)->StructureSize
) ==
211 SMB2_ERROR_STRUCTURE_SIZE2
)
215 * Following commands have data areas so we have to get the location
216 * of the data buffer offset and data buffer length for the particular
219 switch (hdr
->Command
) {
222 ((struct smb2_negotiate_rsp
*)hdr
)->SecurityBufferOffset
);
224 ((struct smb2_negotiate_rsp
*)hdr
)->SecurityBufferLength
);
226 case SMB2_SESSION_SETUP
:
228 ((struct smb2_sess_setup_rsp
*)hdr
)->SecurityBufferOffset
);
230 ((struct smb2_sess_setup_rsp
*)hdr
)->SecurityBufferLength
);
234 ((struct smb2_create_rsp
*)hdr
)->CreateContextsOffset
);
236 ((struct smb2_create_rsp
*)hdr
)->CreateContextsLength
);
238 case SMB2_QUERY_INFO
:
240 ((struct smb2_query_info_rsp
*)hdr
)->OutputBufferOffset
);
242 ((struct smb2_query_info_rsp
*)hdr
)->OutputBufferLength
);
245 case SMB2_QUERY_DIRECTORY
:
247 case SMB2_CHANGE_NOTIFY
:
249 /* BB FIXME for unimplemented cases above */
250 cERROR(1, "no length check for command");
255 * Invalid length or offset probably means data area is invalid, but
256 * we have little choice but to ignore the data area in this case.
259 cERROR(1, "offset %d too large, data area ignored", *off
);
262 } else if (*off
< 0) {
263 cERROR(1, "negative offset %d to data invalid ignore data area",
267 } else if (*len
< 0) {
268 cERROR(1, "negative data length %d invalid, data area ignored",
271 } else if (*len
> 128 * 1024) {
272 cERROR(1, "data area larger than 128K: %d", *len
);
276 /* return pointer to beginning of data area, ie offset from SMB start */
277 if ((*off
!= 0) && (*len
!= 0))
278 return hdr
->ProtocolId
+ *off
;
284 * Calculate the size of the SMB message based on the fixed header
285 * portion, the number of word parameters and the data portion of the message.
288 smb2_calc_size(struct smb2_hdr
*hdr
)
290 struct smb2_pdu
*pdu
= (struct smb2_pdu
*)hdr
;
291 int offset
; /* the offset from the beginning of SMB to data area */
292 int data_length
; /* the length of the variable length data area */
293 /* Structure Size has already been checked to make sure it is 64 */
294 int len
= 4 + le16_to_cpu(pdu
->hdr
.StructureSize
);
297 * StructureSize2, ie length of fixed parameter area has already
298 * been checked to make sure it is the correct length.
300 len
+= le16_to_cpu(pdu
->StructureSize2
);
302 if (has_smb2_data_area
[le16_to_cpu(hdr
->Command
)] == false)
305 smb2_get_data_area_len(&offset
, &data_length
, hdr
);
306 cFYI(1, "SMB2 data length %d offset %d", data_length
, offset
);
308 if (data_length
> 0) {
310 * Check to make sure that data area begins after fixed area,
311 * Note that last byte of the fixed area is part of data area
312 * for some commands, typically those with odd StructureSize,
313 * so we must add one to the calculation (and 4 to account for
314 * the size of the RFC1001 hdr.
316 if (offset
+ 4 + 1 < len
) {
317 cERROR(1, "data area offset %d overlaps SMB2 header %d",
318 offset
+ 4 + 1, len
);
321 len
= 4 + offset
+ data_length
;
325 cFYI(1, "SMB2 len %d", len
);
329 /* Note: caller must free return buffer */
331 cifs_convert_path_to_utf16(const char *from
, struct cifs_sb_info
*cifs_sb
)
334 const char *start_of_path
;
337 /* Windows doesn't allow paths beginning with \ */
339 start_of_path
= from
+ 1;
341 start_of_path
= from
;
342 to
= cifs_strndup_to_utf16(start_of_path
, PATH_MAX
, &len
,
344 cifs_sb
->mnt_cifs_flags
&
345 CIFS_MOUNT_MAP_SPECIAL_CHR
);