1 /*
2    Unix SMB/CIFS implementation.
3    Manage connections_struct structures
4    Copyright (C) Andrew Tridgell 1998
5    Copyright (C) Alexander Bokovoy 2002
6    Copyright (C) Jeremy Allison 2010
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
20 */
21 
22 #include "includes.h"
23 #include "smbd/smbd.h"
24 #include "smbd/globals.h"
25 #include "lib/util/bitmap.h"
26 
27 /****************************************************************************
28  Return the number of open connections.
29 ****************************************************************************/
30 
conn_num_open(struct smbd_server_connection * sconn)31 int conn_num_open(struct smbd_server_connection *sconn)
32 {
33 	return sconn->num_connections;
34 }
35 
36 /****************************************************************************
37  Check if a snum is in use.
38 ****************************************************************************/
39 
conn_snum_used(struct smbd_server_connection * sconn,int snum)40 bool conn_snum_used(struct smbd_server_connection *sconn,
41 		    int snum)
42 {
43 	struct connection_struct *conn;
44 
45 	for (conn=sconn->connections; conn; conn=conn->next) {
46 		if (conn->params->service == snum) {
47 			return true;
48 		}
49 	}
50 
51 	return false;
52 }
53 
54 /****************************************************************************
55  Find first available connection slot, starting from a random position.
56  The randomisation stops problems with the server dieing and clients
57  thinking the server is still available.
58 ****************************************************************************/
59 
conn_new(struct smbd_server_connection * sconn)60 connection_struct *conn_new(struct smbd_server_connection *sconn)
61 {
62 	connection_struct *conn = NULL;
63 
64 	conn = talloc_zero(NULL, connection_struct);
65 	if (conn == NULL) {
66 		DBG_ERR("talloc_zero failed\n");
67 		return NULL;
68 	}
69 	conn->params = talloc(conn, struct share_params);
70 	if (conn->params == NULL) {
71 		DBG_ERR("talloc_zero failed\n");
72 		TALLOC_FREE(conn);
73 		return NULL;
74 	}
75 	conn->vuid_cache = talloc_zero(conn, struct vuid_cache);
76 	if (conn->vuid_cache == NULL) {
77 		DBG_ERR("talloc_zero failed\n");
78 		TALLOC_FREE(conn);
79 		return NULL;
80 	}
81 	conn->connectpath = talloc_strdup(conn, "");
82 	if (conn->connectpath == NULL) {
83 		DBG_ERR("talloc_zero failed\n");
84 		TALLOC_FREE(conn);
85 		return NULL;
86 	}
87 	conn->origpath = talloc_strdup(conn, "");
88 	if (conn->origpath == NULL) {
89 		DBG_ERR("talloc_zero failed\n");
90 		TALLOC_FREE(conn);
91 		return NULL;
92 	}
93 	conn->cwd_fsp = talloc_zero(conn, struct files_struct);
94 	if (conn->cwd_fsp == NULL) {
95 		DBG_ERR("talloc_zero failed\n");
96 		TALLOC_FREE(conn);
97 		return NULL;
98 	}
99 	conn->cwd_fsp->fh = talloc_zero(conn->cwd_fsp, struct fd_handle);
100 	if (conn->cwd_fsp->fh == NULL) {
101 		DBG_ERR("talloc_zero failed\n");
102 		TALLOC_FREE(conn);
103 		return NULL;
104 	}
105 	conn->sconn = sconn;
106 	conn->force_group_gid = (gid_t)-1;
107 	conn->cwd_fsp->fh->fd = -1;
108 	conn->cwd_fsp->fnum = FNUM_FIELD_INVALID;
109 	conn->cwd_fsp->conn = conn;
110 
111 	DLIST_ADD(sconn->connections, conn);
112 	sconn->num_connections++;
113 
114 	return conn;
115 }
116 
117 /****************************************************************************
118  Clear a vuid out of the connection's vuid cache
119 ****************************************************************************/
120 
conn_clear_vuid_cache(connection_struct * conn,uint64_t vuid)121 static void conn_clear_vuid_cache(connection_struct *conn, uint64_t vuid)
122 {
123 	int i;
124 
125 	for (i=0; i<VUID_CACHE_SIZE; i++) {
126 		struct vuid_cache_entry *ent;
127 
128 		ent = &conn->vuid_cache->array[i];
129 
130 		if (ent->vuid == vuid) {
131 			ent->vuid = UID_FIELD_INVALID;
132 			/*
133 			 * We need to keep conn->session_info around
134 			 * if it's equal to ent->session_info as a SMBulogoff
135 			 * is often followed by a SMBtdis (with an invalid
136 			 * vuid). The debug code (or regular code in
137 			 * vfs_full_audit) wants to refer to the
138 			 * conn->session_info pointer to print debug
139 			 * statements. Theoretically this is a bug,
140 			 * as once the vuid is gone the session_info
141 			 * on the conn struct isn't valid any more,
142 			 * but there's enough code that assumes
143 			 * conn->session_info is never null that
144 			 * it's easier to hold onto the old pointer
145 			 * until we get a new sessionsetupX.
146 			 * As everything is hung off the
147 			 * conn pointer as a talloc context we're not
148 			 * leaking memory here. See bug #6315. JRA.
149 			 */
150 			if (conn->session_info == ent->session_info) {
151 				ent->session_info = NULL;
152 			} else {
153 				TALLOC_FREE(ent->session_info);
154 			}
155 			ent->read_only = False;
156 			ent->share_access = 0;
157 		}
158 	}
159 }
160 
161 /****************************************************************************
162  Clear a vuid out of the validity cache, and as the 'owner' of a connection.
163 
164  Called from invalidate_vuid()
165 ****************************************************************************/
166 
conn_clear_vuid_caches(struct smbd_server_connection * sconn,uint64_t vuid)167 void conn_clear_vuid_caches(struct smbd_server_connection *sconn, uint64_t vuid)
168 {
169 	connection_struct *conn;
170 
171 	for (conn=sconn->connections; conn;conn=conn->next) {
172 		if (conn->vuid == vuid) {
173 			conn->vuid = UID_FIELD_INVALID;
174 		}
175 		conn_clear_vuid_cache(conn, vuid);
176 	}
177 }
178 
179 /****************************************************************************
180  Free a conn structure - internal part.
181 ****************************************************************************/
182 
conn_free_internal(connection_struct * conn)183 static void conn_free_internal(connection_struct *conn)
184 {
185 	vfs_handle_struct *handle = NULL, *thandle = NULL;
186 	struct trans_state *state = NULL;
187 
188 	/* Free vfs_connection_struct */
189 	handle = conn->vfs_handles;
190 	while(handle) {
191 		thandle = handle->next;
192 		DLIST_REMOVE(conn->vfs_handles, handle);
193 		if (handle->free_data)
194 			handle->free_data(&handle->data);
195 		handle = thandle;
196 	}
197 
198 	/* Free any pending transactions stored on this conn. */
199 	for (state = conn->pending_trans; state; state = state->next) {
200 		/* state->setup is a talloc child of state. */
201 		SAFE_FREE(state->param);
202 		SAFE_FREE(state->data);
203 	}
204 
205 	free_namearray(conn->veto_list);
206 	free_namearray(conn->hide_list);
207 	free_namearray(conn->veto_oplock_list);
208 	free_namearray(conn->aio_write_behind_list);
209 
210 	ZERO_STRUCTP(conn);
211 	talloc_destroy(conn);
212 }
213 
214 /****************************************************************************
215  Free a conn structure.
216 ****************************************************************************/
217 
conn_free(connection_struct * conn)218 void conn_free(connection_struct *conn)
219 {
220 	if (conn->sconn == NULL) {
221 		conn_free_internal(conn);
222 		return;
223 	}
224 
225 	DLIST_REMOVE(conn->sconn->connections, conn);
226 	SMB_ASSERT(conn->sconn->num_connections > 0);
227 	conn->sconn->num_connections--;
228 
229 	conn_free_internal(conn);
230 }
231 
232 /*
233  * Correctly initialize a share with case options.
234  */
conn_setup_case_options(connection_struct * conn)235 void conn_setup_case_options(connection_struct *conn)
236 {
237 	int snum = conn->params->service;
238 
239 	if (lp_case_sensitive(snum) == Auto) {
240 		/* We will be setting this per packet. Set to be case
241 		* insensitive for now. */
242 		conn->case_sensitive = false;
243 	} else {
244 		conn->case_sensitive = (bool)lp_case_sensitive(snum);
245 	}
246 
247 	conn->case_preserve = lp_preserve_case(snum);
248 	conn->short_case_preserve = lp_short_preserve_case(snum);
249 }
250