summaryrefslogtreecommitdiff
path: root/source3/smbd/conn.c
blob: 44888b777f2e536b6d3014f7434a261f76d7d4df (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
/* 
   Unix SMB/CIFS implementation.
   Manage connections_struct structures
   Copyright (C) Andrew Tridgell 1998
   Copyright (C) Alexander Bokovoy 2002
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"

/* The connections bitmap is expanded in increments of BITMAP_BLOCK_SZ. The
 * maximum size of the bitmap is the largest positive integer, but you will hit
 * the "max connections" limit, looong before that.
 */
#define BITMAP_BLOCK_SZ 128

static connection_struct *Connections;

/* number of open connections */
static struct bitmap *bmap;
static int num_open;

/****************************************************************************
init the conn structures
****************************************************************************/
void conn_init(void)
{
	bmap = bitmap_allocate(BITMAP_BLOCK_SZ);
}

/****************************************************************************
return the number of open connections
****************************************************************************/
int conn_num_open(void)
{
	return num_open;
}


/****************************************************************************
check if a snum is in use
****************************************************************************/
BOOL conn_snum_used(int snum)
{
	connection_struct *conn;
	for (conn=Connections;conn;conn=conn->next) {
		if (conn->params->service == snum) {
			return(True);
		}
	}
	return(False);
}


/****************************************************************************
find a conn given a cnum
****************************************************************************/
connection_struct *conn_find(unsigned cnum)
{
	int count=0;
	connection_struct *conn;

	for (conn=Connections;conn;conn=conn->next,count++) {
		if (conn->cnum == cnum) {
			if (count > 10) {
				DLIST_PROMOTE(Connections, conn);
			}
			return conn;
		}
	}

	return NULL;
}


/****************************************************************************
  find first available connection slot, starting from a random position.
The randomisation stops problems with the server dieing and clients
thinking the server is still available.
****************************************************************************/
connection_struct *conn_new(void)
{
	TALLOC_CTX *mem_ctx;
	connection_struct *conn;
	int i;
        int find_offset = 1;

find_again:
	i = bitmap_find(bmap, find_offset);
	
	if (i == -1) {
                /* Expand the connections bitmap. */
                int             oldsz = bmap->n;
                int             newsz = bmap->n + BITMAP_BLOCK_SZ;
                struct bitmap * nbmap;

                if (newsz <= oldsz) {
                        /* Integer wrap. */
		        DEBUG(0,("ERROR! Out of connection structures\n"));
                        return NULL;
                }

		DEBUG(4,("resizing connections bitmap from %d to %d\n",
                        oldsz, newsz));

                nbmap = bitmap_allocate(newsz);
		if (!nbmap) {
			DEBUG(0,("ERROR! malloc fail.\n"));
			return NULL;
		}

                bitmap_copy(nbmap, bmap);
                bitmap_free(bmap);

                bmap = nbmap;
                find_offset = oldsz; /* Start next search in the new portion. */

                goto find_again;
	}

	/* The bitmap position is used below as the connection number
	 * conn->cnum). This ends up as the TID field in the SMB header,
	 * which is limited to 16 bits (we skip 0xffff which is the
	 * NULL TID).
	 */
	if (i > 65534) {
		DEBUG(0, ("Maximum connection limit reached\n"));
		return NULL;
	}

	if ((mem_ctx=talloc_init("connection_struct"))==NULL) {
		DEBUG(0,("talloc_init(connection_struct) failed!\n"));
		return NULL;
	}

	if (!(conn=TALLOC_ZERO_P(mem_ctx, connection_struct)) ||
	    !(conn->params = TALLOC_P(mem_ctx, struct share_params))) {
		DEBUG(0,("talloc_zero() failed!\n"));
		TALLOC_FREE(mem_ctx);
		return NULL;
	}
	conn->mem_ctx = mem_ctx;
	conn->cnum = i;

	bitmap_set(bmap, i);

	num_open++;

	string_set(&conn->user,"");
	string_set(&conn->dirpath,"");
	string_set(&conn->connectpath,"");
	string_set(&conn->origpath,"");
	
	DLIST_ADD(Connections, conn);

	return conn;
}

/****************************************************************************
 Close all conn structures.
****************************************************************************/

void conn_close_all(void)
{
	connection_struct *conn, *next;
	for (conn=Connections;conn;conn=next) {
		next=conn->next;
		set_current_service(conn, 0, True);
		close_cnum(conn, conn->vuid);
	}
}

/****************************************************************************
 Idle inactive connections.
****************************************************************************/

BOOL conn_idle_all(time_t t, int deadtime)
{
	pipes_struct *plist = NULL;
	BOOL allidle = True;
	connection_struct *conn, *next;

	for (conn=Connections;conn;conn=next) {
		next=conn->next;

		/* Update if connection wasn't idle. */
		if (conn->lastused != conn->lastused_count) {
			conn->lastused = t;
			conn->lastused_count = t;
		}

		/* close dirptrs on connections that are idle */
		if ((t-conn->lastused) > DPTR_IDLE_TIMEOUT) {
			dptr_idlecnum(conn);
		}

		if (conn->num_files_open > 0 || (t-conn->lastused)<deadtime) {
			allidle = False;
		}
	}

	/*
	 * Check all pipes for any open handles. We cannot
	 * idle with a handle open.
	 */

	for (plist = get_first_internal_pipe(); plist; plist = get_next_internal_pipe(plist))
		if (plist->pipe_handles && plist->pipe_handles->count)
			allidle = False;
	
	return allidle;
}

/****************************************************************************
 Clear a vuid out of the validity cache, and as the 'owner' of a connection.
****************************************************************************/

void conn_clear_vuid_cache(uint16 vuid)
{
	connection_struct *conn;
	unsigned int i;

	for (conn=Connections;conn;conn=conn->next) {
		if (conn->vuid == vuid) {
			conn->vuid = UID_FIELD_INVALID;
		}

		for (i=0;i<conn->vuid_cache.entries && i< VUID_CACHE_SIZE;i++) {
			if (conn->vuid_cache.array[i].vuid == vuid) {
				struct vuid_cache_entry *ent = &conn->vuid_cache.array[i];
				ent->vuid = UID_FIELD_INVALID;
				ent->read_only = False;
				ent->admin_user = False;
			}
		}
	}
}

/****************************************************************************
 Free a conn structure - internal part.
****************************************************************************/

void conn_free_internal(connection_struct *conn)
{
 	vfs_handle_struct *handle = NULL, *thandle = NULL;
 	TALLOC_CTX *mem_ctx = NULL;
	struct trans_state *state = NULL;

	/* Free vfs_connection_struct */
	handle = conn->vfs_handles;
	while(handle) {
		DLIST_REMOVE(conn->vfs_handles, handle);
		thandle = handle->next;
		if (handle->free_data)
			handle->free_data(&handle->data);
		handle = thandle;
	}

	/* Free any pending transactions stored on this conn. */
	for (state = conn->pending_trans; state; state = state->next) {
		/* state->setup is a talloc child of state. */
		SAFE_FREE(state->param);
		SAFE_FREE(state->data);
	}

	free_namearray(conn->veto_list);
	free_namearray(conn->hide_list);
	free_namearray(conn->veto_oplock_list);
	free_namearray(conn->aio_write_behind_list);
	
	string_free(&conn->user);
	string_free(&conn->dirpath);
	string_free(&conn->connectpath);
	string_free(&conn->origpath);

	mem_ctx = conn->mem_ctx;
	ZERO_STRUCTP(conn);
	talloc_destroy(mem_ctx);
}

/****************************************************************************
 Free a conn structure.
****************************************************************************/

void conn_free(connection_struct *conn)
{
	DLIST_REMOVE(Connections, conn);

	bitmap_clear(bmap, conn->cnum);
	num_open--;

	conn_free_internal(conn);
}
 
/****************************************************************************
receive a smbcontrol message to forcibly unmount a share
the message contains just a share name and all instances of that
share are unmounted
the special sharename '*' forces unmount of all shares
****************************************************************************/
void msg_force_tdis(int msg_type, struct process_id pid, void *buf, size_t len,
		    void *private_data)
{
	connection_struct *conn, *next;
	fstring sharename;

	fstrcpy(sharename, (const char *)buf);

	if (strcmp(sharename, "*") == 0) {
		DEBUG(1,("Forcing close of all shares\n"));
		conn_close_all();
		return;
	}

	for (conn=Connections;conn;conn=next) {
		next=conn->next;
		if (strequal(lp_servicename(SNUM(conn)), sharename)) {
			DEBUG(1,("Forcing close of share %s cnum=%d\n",
				 sharename, conn->cnum));
			close_cnum(conn, (uint16)-1);
		}
	}
}