summaryrefslogtreecommitdiff
path: root/source3/smbd/connection.c
blob: 01eb9d79f7babd0f1ea1ce405d8b4af4b8cdf00e (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
/* 
   Unix SMB/CIFS implementation.
   connection claim routines
   Copyright (C) Andrew Tridgell 1998

   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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "smbd/smbd.h"
#include "smbd/globals.h"
#include "dbwrap/dbwrap.h"
#include "auth.h"
#include "../lib/tsocket/tsocket.h"
#include "messages.h"
#include "lib/conn_tdb.h"

/****************************************************************************
 Delete a connection record.
****************************************************************************/

bool yield_connection(connection_struct *conn, const char *name)
{
	struct db_record *rec;
	NTSTATUS status;

	DEBUG(3,("Yielding connection to %s\n",name));

	rec = connections_fetch_entry(talloc_tos(), conn, name);
	if (rec == NULL) {
		DEBUG(0, ("connections_fetch_entry failed\n"));
		return False;
	}

	status = dbwrap_record_delete(rec);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG( NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ? 3 : 0,
		       ("deleting connection record returned %s\n",
			nt_errstr(status)));
	}

	TALLOC_FREE(rec);
	return NT_STATUS_IS_OK(status);
}

struct count_stat {
	int curr_connections;
	const char *name;
	bool Clear;
};

/****************************************************************************
 Count the entries belonging to a service in the connection db.
****************************************************************************/

static int count_fn(struct db_record *rec,
		    const struct connections_key *ckey,
		    const struct connections_data *crec,
		    void *udp)
{
	struct count_stat *cs = (struct count_stat *)udp;

	if (crec->cnum == -1) {
		return 0;
	}

	/* If the pid was not found delete the entry from connections.tdb */

	if (cs->Clear && !process_exists(crec->pid) && (errno == ESRCH)) {
		NTSTATUS status;
		DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
			 procid_str_static(&crec->pid), crec->cnum,
			 crec->servicename));

		status = dbwrap_record_delete(rec);
		if (!NT_STATUS_IS_OK(status)) {
			DEBUG(0,("count_fn: tdb_delete failed with error %s\n",
				 nt_errstr(status)));
		}
		return 0;
	}

	if (strequal(crec->servicename, cs->name))
		cs->curr_connections++;

	return 0;
}

/****************************************************************************
 Claim an entry in the connections database.
****************************************************************************/

int count_current_connections( const char *sharename, bool clear  )
{
	struct count_stat cs;
	int ret;

	cs.curr_connections = 0;
	cs.name = sharename;
	cs.Clear = clear;

	/*
	 * This has a race condition, but locking the chain before hand is worse
	 * as it leads to deadlock.
	 */

	/*
	 * become_root() because we might have to open connections.tdb
	 * via ctdb, which is not possible without root.
	 */
	become_root();
	ret = connections_forall(count_fn, &cs);
	unbecome_root();

	if (ret < 0) {
		DEBUG(0,("count_current_connections: traverse of "
			 "connections.tdb failed\n"));
		return 0;
	}

	return cs.curr_connections;
}

bool connections_snum_used(struct smbd_server_connection *unused, int snum)
{
	int active;

	active = count_current_connections(lp_servicename(snum), true);
	if (active > 0) {
		return true;
	}

	return false;
}

/****************************************************************************
 Claim an entry in the connections database.
****************************************************************************/

bool claim_connection(connection_struct *conn, const char *name)
{
	struct db_record *rec;
	struct connections_data crec;
	char *raddr;
	TDB_DATA dbuf;
	NTSTATUS status;

	DEBUG(5,("claiming [%s]\n", name));

	if (!(rec = connections_fetch_entry(talloc_tos(), conn, name))) {
		DEBUG(0, ("connections_fetch_entry failed\n"));
		return False;
	}

	/* Make clear that we require the optional unix_token in the source3 code */
	SMB_ASSERT(conn->session_info->unix_token);

	/* fill in the crec */
	ZERO_STRUCT(crec);
	crec.magic = 0x280267;
	crec.pid = messaging_server_id(conn->sconn->msg_ctx);
	crec.cnum = conn->cnum;
	crec.uid = conn->session_info->unix_token->uid;
	crec.gid = conn->session_info->unix_token->gid;
	strlcpy(crec.servicename, lp_servicename(SNUM(conn)),
		sizeof(crec.servicename));
	crec.start = time(NULL);

	raddr = tsocket_address_inet_addr_string(conn->sconn->remote_address,
						 talloc_tos());
	if (raddr == NULL) {
		return false;
	}

	strlcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine));
	strlcpy(crec.addr, raddr, sizeof(crec.addr));

	dbuf.dptr = (uint8 *)&crec;
	dbuf.dsize = sizeof(crec);

	status = dbwrap_record_store(rec, dbuf, TDB_REPLACE);

	TALLOC_FREE(rec);

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
			 nt_errstr(status)));
		return False;
	}

	return True;
}