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
|
/*
Unix SMB/Netbios implementation.
Version 1.9.
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 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"
extern fstring remote_machine;
static TDB_CONTEXT *tdb;
extern int DEBUGLEVEL;
/****************************************************************************
Return the connection tdb context (used for message send all).
****************************************************************************/
TDB_CONTEXT *conn_tdb_ctx(void)
{
return tdb;
}
/****************************************************************************
Delete a connection record.
****************************************************************************/
BOOL yield_connection(connection_struct *conn,char *name,int max_connections)
{
struct connections_key key;
TDB_DATA kbuf;
if (!tdb) return False;
DEBUG(3,("Yielding connection to %s\n",name));
ZERO_STRUCT(key);
key.pid = sys_getpid();
key.cnum = conn?conn->cnum:-1;
fstrcpy(key.name, name);
dos_to_unix(key.name, True); /* Convert key to unix-codepage */
kbuf.dptr = (char *)&key;
kbuf.dsize = sizeof(key);
tdb_delete(tdb, kbuf);
return(True);
}
struct count_stat {
pid_t mypid;
int curr_connections;
char *name;
BOOL Clear;
};
/****************************************************************************
Count the entries belonging to a service in the connection db.
****************************************************************************/
static int count_fn( TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf, void *udp)
{
struct connections_data crec;
struct count_stat *cs = (struct count_stat *)udp;
if (dbuf.dsize != sizeof(crec))
return 0;
memcpy(&crec, dbuf.dptr, sizeof(crec));
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)) {
DEBUG(2,("pid %u doesn't exist - deleting connections %d [%s]\n",
(unsigned int)crec.pid, crec.cnum, crec.name));
tdb_delete(the_tdb, kbuf);
return 0;
}
if (strequal(crec.name, cs->name))
cs->curr_connections++;
return 0;
}
/****************************************************************************
Claim an entry in the connections database.
****************************************************************************/
BOOL claim_connection(connection_struct *conn,char *name,int max_connections,BOOL Clear)
{
struct connections_key key;
struct connections_data crec;
TDB_DATA kbuf, dbuf, lockkey;
BOOL rec_locked = False;
BOOL ret = True;
if (!tdb) {
tdb = tdb_open(lock_path("connections.tdb"), 0, TDB_CLEAR_IF_FIRST,
O_RDWR | O_CREAT, 0644);
}
if (!tdb)
return False;
/*
* Enforce the max connections parameter.
*/
if (max_connections > 0) {
struct count_stat cs;
cs.mypid = sys_getpid();
cs.curr_connections = 0;
cs.name = lp_servicename(SNUM(conn));
cs.Clear = Clear;
lockkey.dptr = cs.name;
lockkey.dsize = strlen(cs.name)+1;
/*
* Go through and count the connections with hash chain representing the service name
* locked. This is slow but removes race conditions. JRA.
*/
if (tdb_chainlock(tdb, lockkey)) {
DEBUG(0,("claim_connection: tdb_chainlock failed %s\n",
tdb_errorstr(tdb) ));
return False;
}
rec_locked = True;
if (tdb_traverse(tdb, count_fn, &cs) == -1) {
DEBUG(0,("claim_connection: traverse of connections.tdb failed with error %s.\n",
tdb_errorstr(tdb) ));
ret = False;
goto out;
}
if (cs.curr_connections >= max_connections) {
DEBUG(1,("claim_connection: Max connections (%d) exceeded for %s\n",
max_connections, name ));
ret = False;
goto out;
}
}
DEBUG(5,("claiming %s %d\n",name,max_connections));
ZERO_STRUCT(key);
key.pid = sys_getpid();
key.cnum = conn?conn->cnum:-1;
fstrcpy(key.name, name);
dos_to_unix(key.name, True); /* Convert key to unix-codepage */
kbuf.dptr = (char *)&key;
kbuf.dsize = sizeof(key);
/* fill in the crec */
ZERO_STRUCT(crec);
crec.magic = 0x280267;
crec.pid = sys_getpid();
crec.cnum = conn?conn->cnum:-1;
if (conn) {
crec.uid = conn->uid;
crec.gid = conn->gid;
StrnCpy(crec.name,
lp_servicename(SNUM(conn)),sizeof(crec.name)-1);
}
crec.start = time(NULL);
StrnCpy(crec.machine,remote_machine,sizeof(crec.machine)-1);
StrnCpy(crec.addr,conn?conn->client_address:client_addr(),sizeof(crec.addr)-1);
dbuf.dptr = (char *)&crec;
dbuf.dsize = sizeof(crec);
if (tdb_store(tdb, kbuf, dbuf, TDB_REPLACE) != 0) {
DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
tdb_errorstr(tdb) ));
ret = False;
}
out:
if (rec_locked)
tdb_chainunlock(tdb, lockkey);
return ret;
}
|
