2 * Expand msdfs targets based on client IP
4 * Copyright (C) Volker Lendecke, 2004
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
21 #include "system/filesys.h"
22 #include "smbd/smbd.h"
23 #include "../librpc/gen_ndr/ndr_netlogon.h"
24 #include "smbd/globals.h"
26 #include "../lib/tsocket/tsocket.h"
29 #define DBGC_CLASS DBGC_VFS
31 /**********************************************************
32 Under mapfile we expect a table of the following format:
34 IP-Prefix whitespace expansion
37 192.168.234 local.samba.org
38 192.168 remote.samba.org
41 This is to redirect a DFS client to a host close to it.
42 ***********************************************************/
44 static char *read_target_host(TALLOC_CTX
*ctx
, const char *mapfile
,
45 const char *clientaddr
)
52 f
= fopen(mapfile
, "r");
55 DEBUG(0,("can't open IP map %s. Error %s\n",
56 mapfile
, strerror(errno
) ));
60 DEBUG(10, ("Scanning mapfile [%s]\n", mapfile
));
62 while (fgets(buf
, sizeof(buf
), f
) != NULL
) {
64 if ((strlen(buf
) > 0) && (buf
[strlen(buf
)-1] == '\n'))
65 buf
[strlen(buf
)-1] = '\0';
67 DEBUG(10, ("Scanning line [%s]\n", buf
));
69 space
= strchr_m(buf
, ' ');
72 DEBUG(0, ("Ignoring invalid line %s\n", buf
));
78 if (strncmp(clientaddr
, buf
, strlen(buf
)) == 0) {
92 while (isspace(*space
))
95 return talloc_strdup(ctx
, space
);
98 /**********************************************************
100 Expand the msdfs target host using read_target_host
101 explained above. The syntax used in the msdfs link is
103 msdfs:@table-filename@/share
105 Everything between and including the two @-signs is
106 replaced by the substitution string found in the table
109 ***********************************************************/
111 static char *expand_msdfs_target(TALLOC_CTX
*ctx
,
112 connection_struct
*conn
,
115 const struct loadparm_substitution
*lp_sub
=
116 loadparm_s3_global_substitution();
117 char *mapfilename
= NULL
;
118 char *filename_start
= strchr_m(target
, '@');
119 char *filename_end
= NULL
;
120 int filename_len
= 0;
121 char *targethost
= NULL
;
122 char *new_target
= NULL
;
125 if (filename_start
== NULL
) {
126 DEBUG(10, ("No filename start in %s\n", target
));
130 filename_end
= strchr_m(filename_start
+1, '@');
132 if (filename_end
== NULL
) {
133 DEBUG(10, ("No filename end in %s\n", target
));
137 filename_len
= PTR_DIFF(filename_end
, filename_start
+1);
138 mapfilename
= talloc_strdup(ctx
, filename_start
+1);
142 mapfilename
[filename_len
] = '\0';
144 DEBUG(10, ("Expanding from table [%s]\n", mapfilename
));
146 raddr
= tsocket_address_inet_addr_string(conn
->sconn
->remote_address
,
152 targethost
= read_target_host(ctx
, mapfilename
, raddr
);
153 if (targethost
== NULL
) {
154 DEBUG(1, ("Could not expand target host from file %s\n",
159 targethost
= talloc_sub_full(ctx
,
160 lp_servicename(talloc_tos(), lp_sub
, SNUM(conn
)),
161 conn
->session_info
->unix_info
->unix_name
,
163 conn
->session_info
->unix_token
->gid
,
164 conn
->session_info
->unix_info
->sanitized_username
,
165 conn
->session_info
->info
->domain_name
,
168 DEBUG(10, ("Expanded targethost to %s\n", targethost
));
170 /* Replace the part between '@...@' */
171 *filename_start
= '\0';
172 new_target
= talloc_asprintf(ctx
,
181 DEBUG(10, ("New DFS target: %s\n", new_target
));
185 static int expand_msdfs_readlinkat(struct vfs_handle_struct
*handle
,
186 files_struct
*dirfsp
,
187 const struct smb_filename
*smb_fname
,
191 TALLOC_CTX
*ctx
= talloc_tos();
193 char *target
= talloc_array(ctx
, char, PATH_MAX
+1);
205 result
= SMB_VFS_NEXT_READLINKAT(handle
,
214 target
[result
] = '\0';
216 if ((strncmp(target
, "msdfs:", 6) == 0) &&
217 (strchr_m(target
, '@') != NULL
)) {
218 target
= expand_msdfs_target(ctx
, handle
->conn
, target
);
225 len
= MIN(bufsiz
, strlen(target
));
227 memcpy(buf
, target
, len
);
233 static struct vfs_fn_pointers vfs_expand_msdfs_fns
= {
234 .readlinkat_fn
= expand_msdfs_readlinkat
238 NTSTATUS
vfs_expand_msdfs_init(TALLOC_CTX
*ctx
)
240 return smb_register_vfs(SMB_VFS_INTERFACE_VERSION
, "expand_msdfs",
241 &vfs_expand_msdfs_fns
);