1 /*
2 Unix SMB/CIFS implementation.
3 server specific string routines
4 Copyright (C) Andrew Tridgell 2001
5 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2003
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program 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 the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "includes.h"
22 #include "smbd/smbd.h"
23 #include "smbd/globals.h"
24
25 /* Make sure we can't write a string past the end of the buffer */
26
srvstr_push_fn(const char * base_ptr,uint16_t smb_flags2,void * dest,const char * src,int dest_len,int flags,size_t * ret_len)27 NTSTATUS srvstr_push_fn(const char *base_ptr, uint16_t smb_flags2, void *dest,
28 const char *src, int dest_len, int flags, size_t *ret_len)
29 {
30 size_t len;
31 int saved_errno;
32 NTSTATUS status;
33
34 if (dest_len < 0) {
35 return NT_STATUS_INVALID_PARAMETER;
36 }
37
38 saved_errno = errno;
39 errno = 0;
40
41 /* 'normal' push into size-specified buffer */
42 len = push_string_base(base_ptr, smb_flags2, dest, src,
43 dest_len, flags);
44
45 if (errno != 0) {
46 /*
47 * Special case E2BIG, EILSEQ, EINVAL
48 * as they mean conversion errors here,
49 * but we don't generically map them as
50 * they can mean different things in
51 * generic filesystem calls (such as
52 * read xattrs).
53 */
54 if (errno == E2BIG || errno == EILSEQ || errno == EINVAL) {
55 status = NT_STATUS_ILLEGAL_CHARACTER;
56 } else {
57 status = map_nt_error_from_unix_common(errno);
58 /*
59 * Paranoia - Filter out STATUS_MORE_ENTRIES.
60 * I don't think we can get this but it has a
61 * specific meaning to the client.
62 */
63 if (NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
64 status = NT_STATUS_UNSUCCESSFUL;
65 }
66 }
67 DEBUG(10,("character conversion failure "
68 "on string (%s) (%s)\n",
69 src, strerror(errno)));
70 } else {
71 /* Success - restore untouched errno. */
72 errno = saved_errno;
73 *ret_len = len;
74 status = NT_STATUS_OK;
75 }
76 return status;
77 }
78
79 /*******************************************************************
80 Add a string to the end of a smb_buf, adjusting bcc and smb_len.
81 Return the bytes added
82 ********************************************************************/
83
message_push_string(uint8_t ** outbuf,const char * str,int flags)84 ssize_t message_push_string(uint8_t **outbuf, const char *str, int flags)
85 {
86 size_t buf_size = smb_len(*outbuf) + 4;
87 size_t grow_size;
88 size_t result = 0;
89 uint8_t *tmp;
90 NTSTATUS status;
91
92 /*
93 * We need to over-allocate, now knowing what srvstr_push will
94 * actually use. This is very generous by incorporating potential
95 * padding, the terminating 0 and at most 4 chars per UTF-16 code
96 * point.
97 */
98 grow_size = (strlen(str) + 2) * 4;
99
100 if (!(tmp = talloc_realloc(NULL, *outbuf, uint8_t,
101 buf_size + grow_size))) {
102 DEBUG(0, ("talloc failed\n"));
103 return -1;
104 }
105
106 status = srvstr_push((char *)tmp, SVAL(tmp, smb_flg2),
107 tmp + buf_size, str, grow_size, flags, &result);
108
109 if (!NT_STATUS_IS_OK(status)) {
110 DEBUG(0, ("srvstr_push failed\n"));
111 return -1;
112 }
113
114 /*
115 * Ensure we clear out the extra data we have
116 * grown the buffer by, but not written to.
117 */
118 if (buf_size + result < buf_size) {
119 return -1;
120 }
121 if (grow_size < result) {
122 return -1;
123 }
124
125 memset(tmp + buf_size + result, '\0', grow_size - result);
126
127 set_message_bcc((char *)tmp, smb_buflen(tmp) + result);
128
129 *outbuf = tmp;
130
131 return result;
132 }
133