socket-proxyd: Add --listener option for listener/destination pairs.

This commit is contained in:
David Strauss 2013-11-25 10:44:48 +10:00
parent 828db5d84a
commit adcf4c81c5
3 changed files with 121 additions and 23 deletions

1
TODO
View File

@ -105,7 +105,6 @@ Features:
* remove NSS usage from PID 1 (notably the specifiers)
* socket-proxyd:
- Support multiple inherited sockets mapped to different remote hosts
- Use a nonblocking alternative to getaddrinfo
- Until we can start daemons directly, find a less ugly, less racy alternative than shell scripts for the second man page example.
- Support starting daemons directly without requiring a shell script; update man pages

View File

@ -31,6 +31,12 @@
<surname>Strauss</surname>
<email>david@davidstrauss.net</email>
</author>
<author>
<contrib>Developer</contrib>
<firstname>Lennart</firstname>
<surname>Poettering</surname>
<email>lennart@poettering.net</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
@ -83,6 +89,17 @@
<title>Options</title>
<para>The following options are understood:</para>
<variablelist>
<varlistentry>
<term><option>-l</option></term>
<term><option>--listener</option></term>
<listitem>
<para>Restricts listening to a
single inherited socket, specified
as a file descriptor. By default,
the proxy listens on all inherited
sockets.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>-h</option></term>
<term><option>--help</option></term>
@ -196,8 +213,12 @@ while [ ! -f /tmp/nginx.pid ]
do
/usr/bin/inotifywait /tmp/nginx.pid
done
exec /usr/bin/systemd-socket-proxyd localhost 8080]]>
exec /usr/bin/systemd-socket-proxyd localhost:8080]]>
</programlisting>
<para>Make it executable:</para>
<programlisting>
<![CDATA[chmod 755 /usr/bin/socket-proxyd-nginx.sh]]>
</programlisting>
</example>
<example label="nginx configuration">
<title>
@ -215,6 +236,63 @@ server {
<![CDATA[# systemctl enable proxy-with-nginx.socket
# systemctl start proxy-with-nginx.socket
$ curl http://localhost:80/]]>
</programlisting>
</example>
</refsect2>
<refsect2>
<title>Multiple Listeners with Multiple Destinations</title>
<para>When using namespaces, it may be useful to
have multiple listeners with each going to a unique
destination. systemd always passes sockets into
services in the order specified in the socket
unit, beginning with file descriptor 3.</para>
<para>In this example, port <literal>80</literal>
will proxy to <literal>localhost:8080</literal>,
and port <literal>443</literal> will proxy to
<literal>localhost:8443</literal>.</para>
<example label="proxy socket unit">
<title>/etc/systemd/system/multi-destination.socket</title>
<programlisting>
<![CDATA[[Socket]
ListenStream=80
ListenStream=443
[Install]
WantedBy=sockets.target]]>
</programlisting>
</example>
<example label="proxy service unit">
<title>/etc/systemd/system/multi-destination.service</title>
<programlisting>
<![CDATA[[Service]
ExecStart=/usr/bin/socket-proxyd-multi-destination.sh
PrivateTmp=true
PrivateNetwork=true]]>
</programlisting>
</example>
<example label="shell script">
<title>
/usr/bin/socket-proxyd-multi-destination.sh</title>
<programlisting>
<![CDATA[#!/bin/sh
/usr/bin/systemd-socket-proxyd --listener=3 localhost:8080 &
/usr/bin/systemd-socket-proxyd --listener=4 localhost:8443 &
wait]]>
</programlisting>
<para>Make it executable:</para>
<programlisting>
<![CDATA[chmod 755 /usr/bin/socket-proxyd-multi-destination.sh]]>
</programlisting>
</example>
<example label="commands">
<programlisting>
<![CDATA[# systemctl enable multi-destination.socket
# systemctl start multi-destination.socket
$ curl http://localhost/
$ curl https://localhost/]]>
</programlisting>
</example>
</refsect2>

View File

@ -66,6 +66,7 @@ typedef struct Connection {
} Connection;
static const char *arg_remote_host = NULL;
static int arg_listener = -1;
static void connection_free(Connection *c) {
assert(c);
@ -554,8 +555,9 @@ static int help(void) {
printf("%s [HOST:PORT]\n"
"%s [SOCKET]\n\n"
"Bidirectionally proxy local sockets to another (possibly remote) socket.\n\n"
" -h --help Show this help\n"
" --version Show package version\n",
" -l --listener=FD Listen on a specific, single file descriptor.\n"
" -h --help Show this help\n"
" --version Show package version\n",
program_invocation_short_name,
program_invocation_short_name);
@ -565,22 +567,22 @@ static int help(void) {
static int parse_argv(int argc, char *argv[]) {
enum {
ARG_VERSION = 0x100,
ARG_IGNORE_ENV
ARG_VERSION = 0x100
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, ARG_VERSION },
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, ARG_VERSION },
{ "listener", required_argument, NULL, 'l' },
{}
};
int c;
int c, fd;
assert(argc >= 0);
assert(argv);
while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
while ((c = getopt_long(argc, argv, "hl:", options, NULL)) >= 0) {
switch (c) {
@ -592,6 +594,18 @@ static int parse_argv(int argc, char *argv[]) {
puts(SYSTEMD_FEATURES);
return 0;
case 'l':
if (safe_atoi(optarg, &fd) < 0) {
log_error("Failed to parse listener file descriptor: %s", optarg);
return -EINVAL;
}
if (fd < SD_LISTEN_FDS_START) {
log_error("Listener file descriptor must be at least %d.", SD_LISTEN_FDS_START);
return -EINVAL;
}
arg_listener = fd;
break;
case '?':
return -EINVAL;
@ -632,19 +646,26 @@ int main(int argc, char *argv[]) {
goto finish;
}
n = sd_listen_fds(1);
if (n < 0) {
log_error("Failed to receive sockets from parent.");
r = n;
goto finish;
} else if (n == 0) {
log_error("Didn't get any sockets passed in.");
r = -EINVAL;
goto finish;
}
for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd++) {
r = add_listen_socket(&context, event, fd);
if (arg_listener == -1) {
n = sd_listen_fds(1);
if (n < 0) {
log_error("Failed to receive sockets from parent.");
r = n;
goto finish;
} else if (n == 0) {
log_error("Didn't get any sockets passed in.");
r = -EINVAL;
goto finish;
}
log_info("Listening on %d inherited socket(s), starting with fd=%d.", n, SD_LISTEN_FDS_START);
for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd++) {
r = add_listen_socket(&context, event, fd);
if (r < 0)
goto finish;
}
} else {
log_info("Listening on single inherited socket fd=%d.", arg_listener);
r = add_listen_socket(&context, event, arg_listener);
if (r < 0)
goto finish;
}