2 Unix SMB/CIFS implementation.
3 Check access based on valid users, read list and friends
4 Copyright (C) Volker Lendecke 2005
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 "smbd/globals.h"
22 #include "../libcli/security/security.h"
25 * No prefix means direct username
26 * @name means netgroup first, then unix group
27 * &name means netgroup
28 * +name means unix group
29 * + and & may be combined
32 static bool do_group_checks(const char **name, const char **pattern)
34 if ((*name)[0] == '@') {
40 if (((*name)[0] == '+') && ((*name)[1] == '&')) {
46 if ((*name)[0] == '+') {
52 if (((*name)[0] == '&') && ((*name)[1] == '+')) {
58 if ((*name)[0] == '&') {
67 static bool token_contains_name(TALLOC_CTX *mem_ctx,
70 const char *sharename,
71 const struct security_token *token,
76 enum lsa_SidType type;
78 if (username != NULL) {
79 name = talloc_sub_basic(mem_ctx, username, domain, name);
81 if (sharename != NULL) {
82 name = talloc_string_sub(mem_ctx, name, "%S", sharename);
86 /* This is too security sensitive, better panic than return a
87 * result that might be interpreted in a wrong way. */
88 smb_panic("substitutions failed");
91 /* check to see is we already have a SID */
93 if ( string_to_sid( &sid, name ) ) {
94 DEBUG(5,("token_contains_name: Checking for SID [%s] in token\n", name));
95 return nt_token_check_sid( &sid, token );
98 if (!do_group_checks(&name, &prefix)) {
99 if (!lookup_name_smbconf(mem_ctx, name, LOOKUP_NAME_ALL,
100 NULL, NULL, &sid, &type)) {
101 DEBUG(5, ("lookup_name %s failed\n", name));
104 if (type != SID_NAME_USER) {
105 DEBUG(5, ("%s is a %s, expected a user\n",
106 name, sid_type_lookup(type)));
109 return nt_token_check_sid(&sid, token);
112 for (/* initialized above */ ; *prefix != '\0'; prefix++) {
113 if (*prefix == '+') {
114 if (!lookup_name_smbconf(mem_ctx, name,
115 LOOKUP_NAME_ALL|LOOKUP_NAME_GROUP,
116 NULL, NULL, &sid, &type)) {
117 DEBUG(5, ("lookup_name %s failed\n", name));
120 if ((type != SID_NAME_DOM_GRP) &&
121 (type != SID_NAME_ALIAS) &&
122 (type != SID_NAME_WKN_GRP)) {
123 DEBUG(5, ("%s is a %s, expected a group\n",
124 name, sid_type_lookup(type)));
127 if (nt_token_check_sid(&sid, token)) {
132 if (*prefix == '&') {
134 if (user_in_netgroup(mem_ctx, username, name)) {
140 smb_panic("got invalid prefix from do_groups_check");
146 * Check whether a user is contained in the list provided.
148 * Please note that the user name and share names passed in here mainly for
149 * the substitution routines that expand the parameter values, the decision
150 * whether a user is in the list is done after a lookup_name on the expanded
151 * parameter value, solely based on comparing the SIDs in token.
153 * The other use is the netgroup check when using @group or &group.
156 bool token_contains_name_in_list(const char *username,
158 const char *sharename,
159 const struct security_token *token,
168 if ( (mem_ctx = talloc_new(NULL)) == NULL ) {
169 smb_panic("talloc_new failed");
172 while (*list != NULL) {
173 if (token_contains_name(mem_ctx, username, domain, sharename,
175 TALLOC_FREE(mem_ctx);
181 TALLOC_FREE(mem_ctx);
186 * Check whether the user described by "token" has access to share snum.
188 * This looks at "invalid users", "valid users" and "only user/username"
190 * Please note that the user name and share names passed in here mainly for
191 * the substitution routines that expand the parameter values, the decision
192 * whether a user is in the list is done after a lookup_name on the expanded
193 * parameter value, solely based on comparing the SIDs in token.
195 * The other use is the netgroup check when using @group or &group.
198 bool user_ok_token(const char *username, const char *domain,
199 const struct security_token *token, int snum)
201 if (lp_invalid_users(snum) != NULL) {
202 if (token_contains_name_in_list(username, domain,
203 lp_servicename(snum),
205 lp_invalid_users(snum))) {
206 DEBUG(10, ("User %s in 'invalid users'\n", username));
211 if (lp_valid_users(snum) != NULL) {
212 if (!token_contains_name_in_list(username, domain,
213 lp_servicename(snum), token,
214 lp_valid_users(snum))) {
215 DEBUG(10, ("User %s not in 'valid users'\n",
221 if (lp_onlyuser(snum)) {
223 list[0] = lp_username(snum);
225 if ((list[0] == NULL) || (*list[0] == '\0')) {
226 DEBUG(0, ("'only user = yes' and no 'username ='\n"));
229 if (!token_contains_name_in_list(NULL, domain,
230 lp_servicename(snum),
232 DEBUG(10, ("%s != 'username'\n", username));
237 DEBUG(10, ("user_ok_token: share %s is ok for unix user %s\n",
238 lp_servicename(snum), username));
244 * Check whether the user described by "token" is restricted to read-only
245 * access on share snum.
247 * This looks at "invalid users", "valid users" and "only user/username"
249 * Please note that the user name and share names passed in here mainly for
250 * the substitution routines that expand the parameter values, the decision
251 * whether a user is in the list is done after a lookup_name on the expanded
252 * parameter value, solely based on comparing the SIDs in token.
254 * The other use is the netgroup check when using @group or &group.
257 bool is_share_read_only_for_token(const char *username,
259 const struct security_token *token,
260 connection_struct *conn)
262 int snum = SNUM(conn);
263 bool result = conn->read_only;
265 if (lp_readlist(snum) != NULL) {
266 if (token_contains_name_in_list(username, domain,
267 lp_servicename(snum), token,
268 lp_readlist(snum))) {
273 if (lp_writelist(snum) != NULL) {
274 if (token_contains_name_in_list(username, domain,
275 lp_servicename(snum), token,
276 lp_writelist(snum))) {
281 DEBUG(10,("is_share_read_only_for_user: share %s is %s for unix user "
282 "%s\n", lp_servicename(snum),
283 result ? "read-only" : "read-write", username));