/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
#include <getopt.h>
#include <poll.h>
#include <stddef.h>
#include <string.h>
#include <unistd.h>
#include "sd-bus.h"
#include "sd-daemon.h"
#include "bus-internal.h"
#include "bus-util.h"
#include "build.h"
#include "log.h"
#include "util.h"
#define DEFAULT_BUS_PATH "unix:path=/run/dbus/system_bus_socket"
const char *arg_bus_path = DEFAULT_BUS_PATH;
static int help(void) {
printf("%s [OPTIONS...]\n\n"
"STDIO or socket-activatable proxy to a given DBus endpoint.\n\n"
" -h --help Show this help\n"
" --version Show package version\n"
" --bus-path=PATH Path to the kernel bus (default: %s)\n",
program_invocation_short_name, DEFAULT_BUS_PATH);
return 0;
}
static int parse_argv(int argc, char *argv[]) {
enum {
ARG_VERSION = 0x100,
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "bus-path", required_argument, NULL, 'p' },
{ NULL, 0, NULL, 0 }
};
int c;
assert(argc >= 0);
assert(argv);
while ((c = getopt_long(argc, argv, "hsup:", options, NULL)) >= 0) {
switch (c) {
case 'h':
help();
return 0;
case ARG_VERSION:
return version();
case '?':
return -EINVAL;
case 'p':
arg_bus_path = optarg;
break;
default:
log_error("Unknown option code %c", c);
return -EINVAL;
}
}
return 1;
}
int main(int argc, char *argv[]) {
_cleanup_(sd_bus_unrefp) sd_bus *a = NULL, *b = NULL;
sd_id128_t server_id;
bool is_unix;
int r, in_fd, out_fd;
log_set_target(LOG_TARGET_JOURNAL_OR_KMSG);
log_parse_environment();
log_open();
r = parse_argv(argc, argv);
if (r <= 0)
goto finish;
r = sd_listen_fds(0);
if (r == 0) {
in_fd = STDIN_FILENO;
out_fd = STDOUT_FILENO;
} else if (r == 1) {
in_fd = SD_LISTEN_FDS_START;
out_fd = SD_LISTEN_FDS_START;
} else {
log_error("Illegal number of file descriptors passed\n");
goto finish;
}
is_unix =
sd_is_socket(in_fd, AF_UNIX, 0, 0) > 0 &&
sd_is_socket(out_fd, AF_UNIX, 0, 0) > 0;
r = sd_bus_new(&a);
if (r < 0) {
log_error_errno(r, "Failed to allocate bus: %m");
goto finish;
}
r = sd_bus_set_address(a, arg_bus_path);
if (r < 0) {
log_error_errno(r, "Failed to set address to connect to: %m");
goto finish;
}
r = sd_bus_negotiate_fds(a, is_unix);
if (r < 0) {
log_error_errno(r, "Failed to set FD negotiation: %m");
goto finish;
}
r = sd_bus_start(a);
if (r < 0) {
log_error_errno(r, "Failed to start bus client: %m");
goto finish;
}
r = sd_bus_get_bus_id(a, &server_id);
if (r < 0) {
log_error_errno(r, "Failed to get server ID: %m");
goto finish;
}
r = sd_bus_new(&b);
if (r < 0) {
log_error_errno(r, "Failed to allocate bus: %m");
goto finish;
}
r = sd_bus_set_fd(b, in_fd, out_fd);
if (r < 0) {
log_error_errno(r, "Failed to set fds: %m");
goto finish;
}
r = sd_bus_set_server(b, 1, server_id);
if (r < 0) {
log_error_errno(r, "Failed to set server mode: %m");
goto finish;
}
r = sd_bus_negotiate_fds(b, is_unix);
if (r < 0) {
log_error_errno(r, "Failed to set FD negotiation: %m");
goto finish;
}
r = sd_bus_set_anonymous(b, true);
if (r < 0) {
log_error_errno(r, "Failed to set anonymous authentication: %m");
goto finish;
}
r = sd_bus_start(b);
if (r < 0) {
log_error_errno(r, "Failed to start bus client: %m");
goto finish;
}
for (;;) {
_cleanup_(sd_bus_message_unrefp)sd_bus_message *m = NULL;
int events_a, events_b, fd;
uint64_t timeout_a, timeout_b, t;
struct timespec _ts, *ts;
r = sd_bus_process(a, &m);
if (r < 0) {
log_error_errno(r, "Failed to process bus a: %m");
goto finish;
}
if (m) {
r = sd_bus_send(b, m, NULL);
if (r < 0) {
log_error_errno(r, "Failed to send message: %m");
goto finish;
}
}
if (r > 0)
continue;
r = sd_bus_process(b, &m);
if (r < 0) {
/* treat 'connection reset by peer' as clean exit condition */
if (r == -ECONNRESET)
r = 0;
goto finish;
}
if (m) {
r = sd_bus_send(a, m, NULL);
if (r < 0) {
log_error_errno(r, "Failed to send message: %m");
goto finish;
}
}
if (r > 0)
continue;
fd = sd_bus_get_fd(a);
if (fd < 0) {
r = fd;
log_error_errno(r, "Failed to get fd: %m");
goto finish;
}
events_a = sd_bus_get_events(a);
if (events_a < 0) {
r = events_a;
log_error_errno(r, "Failed to get events mask: %m");
goto finish;
}
r = sd_bus_get_timeout(a, &timeout_a);
if (r < 0) {
log_error_errno(r, "Failed to get timeout: %m");
goto finish;
}
events_b = sd_bus_get_events(b);
if (events_b < 0) {
r = events_b;
log_error_errno(r, "Failed to get events mask: %m");
goto finish;
}
r = sd_bus_get_timeout(b, &timeout_b);
if (r < 0) {
log_error_errno(r, "Failed to get timeout: %m");
goto finish;
}
t = timeout_a;
if (t == (uint64_t) -1 || (timeout_b != (uint64_t) -1 && timeout_b < timeout_a))
t = timeout_b;
if (t == (uint64_t) -1)
ts = NULL;
else {
usec_t nw;
nw = now(CLOCK_MONOTONIC);
if (t > nw)
t -= nw;
else
t = 0;
ts = timespec_store(&_ts, t);
}
{
struct pollfd p[3] = {
{.fd = fd, .events = events_a, },
{.fd = STDIN_FILENO, .events = events_b & POLLIN, },
{.fd = STDOUT_FILENO, .events = events_b & POLLOUT, }};
r = ppoll(p, ELEMENTSOF(p), ts, NULL);
}
if (r < 0) {
log_error("ppoll() failed: %m");
goto finish;
}
}
finish:
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}