]>
git.ipfire.org Git - thirdparty/squid.git/blob - src/icmp/pinger.cc
2 * $Id: pinger.cc,v 1.62 2008/02/26 21:49:35 amosjeffries Exp $
4 * DEBUG: section 42 ICMP Pinger program
5 * AUTHOR: Duane Wessels
7 * SQUID Web Proxy Cache http://www.squid-cache.org/
8 * ----------------------------------------------------------
10 * Squid is the result of efforts by numerous individuals from
11 * the Internet community; see the CONTRIBUTORS file for full
12 * details. Many organizations have provided support for Squid's
13 * development; see the SPONSORS file for full details. Squid is
14 * Copyrighted (C) 2001 by the Regents of the University of
15 * California; see the COPYRIGHT file for full details. Squid
16 * incorporates software developed and/or copyrighted by other
17 * sources; see the CREDITS file for full details.
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation; either version 2 of the License, or
22 * (at your option) any later version.
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
29 * You should have received a copy of the GNU General Public License
30 * along with this program; if not, write to the Free Software
31 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
35 #define SQUID_HELPER 1
38 \defgroup pinger pinger
39 \ingroup ExternalPrograms
41 * Although it would be possible for Squid to send and receive
42 * ICMP messages directly, we use an external process for
43 * two important reasons:
45 \li Because squid handles many filedescriptors simultaneously,
46 * we get much more accurate RTT measurements when ICMP is
47 * handled by a separate process.
49 \li Superuser privileges are required to send and receive ICMP.
50 * Rather than require Squid to be started as root, we prefer
51 * to have the smaller and simpler pinger program installed
52 * with setuid permissions.
55 * If you want to use Squid's ICMP features (highly recommended!)
56 * When USE_ICMP is defined, Squid will send ICMP pings
57 * to origin server sites.
58 * This information is used in numerous ways:
59 \li - Sent in ICP replies so neighbor caches know how close
60 * you are to the source.
61 \li - For finding the closest instance of a URN.
62 \li - With the 'test_reachability' option. Squid will return
63 * ICP_OP_MISS_NOFETCH for sites which it cannot ping.
67 #include "SquidTime.h"
73 #include "IcmpPinger.h"
83 #define PINGER_TIMEOUT 5
85 /* windows uses the control socket for feedback to squid */
86 #define LINK_TO_SQUID squid_link
88 // windows still requires WSAFD but there are too many dependancy problems
89 // to just link to win32.cc where it is normally defined.
92 Win32__WSAFDIsSet(int fd
, fd_set FAR
* set
)
94 fde
*F
= &fd_table
[fd
];
95 SOCKET s
= F
->win32
.handle
;
97 return __WSAFDIsSet(s
, set
);
102 #define PINGER_TIMEOUT 10
104 /* non-windows use STDOUT for feedback to squid */
105 #define LINK_TO_SQUID 1
107 #endif /* _SQUID_MSWIN_ */
109 // ICMP Engines are declared global here so they can call each other easily.
116 int icmp_pkts_sent
= 0;
120 \par This is the pinger external process.
126 main(int argc
, char *argv
[])
133 const char *debug_args
= "ALL,10";
135 time_t last_check_time
= 0;
138 * cevans - do this first. It grabs a raw socket. After this we can
141 int icmp4_worker
= -1;
143 int icmp6_worker
= -1;
147 /** start by initializing the pinger debug cache.log-pinger. */
148 if ((t
= getenv("SQUID_DEBUG")))
149 debug_args
= xstrdup(t
);
153 _db_init(NULL
, debug_args
);
155 debugs(42, 0, "pinger: Initialising ICMP pinger ...");
157 icmp4_worker
= icmp4
.Open();
158 if (icmp4_worker
< 0) {
159 debugs(42, 0, "pinger: Unable to start ICMP pinger.");
161 max_fd
= max(max_fd
, icmp4_worker
);
164 icmp6_worker
= icmp6
.Open();
165 if (icmp6_worker
<0 ) {
166 debugs(42, 0, "pinger: Unable to start ICMPv6 pinger.");
168 max_fd
= max(max_fd
, icmp6_worker
);
171 /** abort if neither worker could open a socket. */
172 if (icmp4_worker
== -1) {
174 if (icmp6_worker
== -1)
177 debugs(42, 0, "FATAL: pinger: Unable to open any ICMP sockets.");
182 if ( (squid_link
= control
.Open()) < 0) {
183 debugs(42, 0, "FATAL: pinger: Unable to setup Pinger control sockets.");
188 exit(1); // fatal error if the control channel fails.
190 max_fd
= max(max_fd
, squid_link
);
196 tv
.tv_sec
= PINGER_TIMEOUT
;
199 if (icmp4_worker
>= 0) {
200 FD_SET(icmp4_worker
, &R
);
204 if (icmp6_worker
>= 0) {
205 FD_SET(icmp6_worker
, &R
);
208 FD_SET(squid_link
, &R
);
209 x
= select(10, &R
, NULL
, NULL
, &tv
);
213 debugs(42, 0, HERE
<< " FATAL Shutdown. select()==" << x
<< ", ERR: " << xstrerror());
218 if (FD_ISSET(squid_link
, &R
)) {
223 if (icmp6_worker
>= 0 && FD_ISSET(icmp6_worker
, &R
)) {
228 if (icmp4_worker
>= 0 && FD_ISSET(icmp4_worker
, &R
)) {
232 if (PINGER_TIMEOUT
+ last_check_time
< squid_curtime
) {
233 if (send(LINK_TO_SQUID
, &tv
, 0, 0) < 0) {
234 debugs(42, 0, "pinger: Closing. No requests in last " << PINGER_TIMEOUT
<< " seconds.");
239 last_check_time
= squid_curtime
;
250 main(int argc
, char *argv
[])
252 fprintf(stderr
, "%s: ICMP support not compiled in.\n", argv
[0]);
256 #endif /* USE_ICMP */