1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /*
27 * The seek message is sent to set the current file pointer for FID.
28 * This request should generally only be used by clients wishing to
29 * find the size of a file, since all read and write requests include
30 * the read or write file position as part of the SMB. This request
31 * is inappropriate for large files, as the offsets specified are only
32 * 32 bits.
33 *
34 * The CIFS/1.0 (1996) spec contains the following incomplete statement:
35 *
36 * "A seek which results in an Offset which can not be expressed
37 * in 32 bits returns the least significant."
38 *
39 * It would probably be a mistake to make an assumption about what this
40 * statement means. So, for now, we return an error if the resultant
41 * file offset is beyond the 32-bit limit.
42 */
43
44 #include <smbsrv/smb_kproto.h>
45
46
47 /*
48 * smb_com_seek
49 *
50 * Client Request Description
51 * ================================== =================================
52 * UCHAR WordCount; Count of parameter words = 4
53 * USHORT Fid; File handle
54 * USHORT Mode; Seek mode: 0, 1 or 2
55 * LONG Offset; Relative offset
56 * USHORT ByteCount; Count of data bytes = 0
57 *
58 * The starting point of the seek is set by Mode:
59 *
60 * 0 seek from start of file
61 * 1 seek from current current position
62 * 2 seek from end of file
63 *
64 * The "current position" reflects the offset plus data length specified in
65 * the previous read, write or seek request, and the pointer set by this
66 * command will be replaced by the offset specified in the next read, write
67 * or seek command.
68 *
69 * Server Response Description
70 * ================================== =================================
71 * UCHAR WordCount; Count of parameter words = 2
72 * ULONG Offset; Offset from start of file
73 * USHORT ByteCount; Count of data bytes = 0
74 *
75 * The response returns the new file pointer in Offset, which is expressed
76 * as the offset from the start of the file, and may be beyond the current
77 * end of file. An attempt to seek before the start of the file sets the
78 * current file pointer to the start of the file.
79 */
80 smb_sdrc_t
81 smb_pre_seek(smb_request_t *sr)
82 {
83 DTRACE_SMB_1(op__Seek__start, smb_request_t *, sr);
84 return (SDRC_SUCCESS);
85 }
86
87 void
88 smb_post_seek(smb_request_t *sr)
89 {
90 DTRACE_SMB_1(op__Seek__done, smb_request_t *, sr);
91 }
92
93 smb_sdrc_t
94 smb_com_seek(smb_request_t *sr)
95 {
96 ushort_t mode;
97 int32_t off;
98 uint32_t off_ret;
99 int rc;
100
101 if (smbsr_decode_vwv(sr, "wwl", &sr->smb_fid, &mode, &off) != 0)
102 return (SDRC_ERROR);
103
104 smbsr_lookup_file(sr);
105 if (sr->fid_ofile == NULL) {
106 smbsr_error(sr, NT_STATUS_INVALID_HANDLE, ERRDOS, ERRbadfid);
107 return (SDRC_ERROR);
108 }
109
110 sr->user_cr = smb_ofile_getcred(sr->fid_ofile);
111
112 if ((rc = smb_ofile_seek(sr->fid_ofile, mode, off, &off_ret)) != 0) {
113 if (rc == EINVAL) {
114 smbsr_error(sr, 0, ERRDOS, ERRbadfunc);
115 return (SDRC_ERROR);
116 } else {
117 smbsr_error(sr, 0, ERRSRV, ERRerror);
118 return (SDRC_ERROR);
119 }
120 }
121
122 if (smbsr_encode_result(sr, 2, 0, "blw", 2, off_ret, 0))
123 return (SDRC_ERROR);
124
125 return (SDRC_SUCCESS);
126 }