stdio-bridge.c revision 3f6fd1ba65f962702753c4ad284b588e59689a23
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
Copyright 2013 Daniel Mack
Copyright 2014 Kay Sievers
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 <stddef.h>
#include <string.h>
#include <unistd.h>
#include "sd-daemon.h"
#include "sd-bus.h"
#include "bus-internal.h"
#include "bus-util.h"
#include "def.h"
#include "formats-util.h"
#include "log.h"
#include "proxy.h"
#include "strv.h"
#include "util.h"
static char *arg_address = NULL;
static char *arg_command_line_buffer = NULL;
static int help(void) {
printf("%s [OPTIONS...]\n\n"
"Connect STDIO to a given bus address.\n\n"
" -h --help Show this help\n"
" --version Show package version\n"
" --machine=MACHINE Connect to specified machine\n"
" --address=ADDRESS Connect to the bus specified by ADDRESS\n"
" (default: " DEFAULT_SYSTEM_BUS_ADDRESS ")\n",
program_invocation_short_name);
return 0;
}
static int parse_argv(int argc, char *argv[]) {
enum {
ARG_VERSION = 0x100,
ARG_ADDRESS,
ARG_MACHINE,
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, ARG_VERSION },
{ "address", required_argument, NULL, ARG_ADDRESS },
{ "machine", required_argument, NULL, ARG_MACHINE },
{},
};
int c;
assert(argc >= 0);
assert(argv);
while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
switch (c) {
case 'h':
help();
return 0;
case ARG_VERSION:
return version();
case ARG_ADDRESS: {
char *a;
a = strdup(optarg);
if (!a)
return log_oom();
free(arg_address);
arg_address = a;
break;
}
case ARG_MACHINE: {
_cleanup_free_ char *e = NULL;
char *a;
e = bus_address_escape(optarg);
if (!e)
return log_oom();
a = strjoin("x-machine-kernel:machine=", e, ";x-machine-unix:machine=", e, NULL);
if (!a)
return log_oom();
free(arg_address);
arg_address = a;
break;
}
case '?':
return -EINVAL;
default:
assert_not_reached("Unhandled option");
}
/* If the first command line argument is only "x" characters
* we'll write who we are talking to into it, so that "ps" is
* explanatory */
arg_command_line_buffer = argv[optind];
if (argc > optind + 1 || (arg_command_line_buffer && !in_charset(arg_command_line_buffer, "x"))) {
log_error("Too many arguments");
return -EINVAL;
}
if (!arg_address) {
arg_address = strdup(DEFAULT_SYSTEM_BUS_ADDRESS);
if (!arg_address)
return log_oom();
}
return 1;
}
static int rename_service(sd_bus *a, sd_bus *b) {
_cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
_cleanup_free_ char *p = NULL, *name = NULL;
const char *comm;
char **cmdline;
uid_t uid;
pid_t pid;
int r;
assert(a);
assert(b);
r = sd_bus_get_owner_creds(b, SD_BUS_CREDS_EUID|SD_BUS_CREDS_PID|SD_BUS_CREDS_CMDLINE|SD_BUS_CREDS_COMM|SD_BUS_CREDS_AUGMENT, &creds);
if (r < 0)
return r;
r = sd_bus_creds_get_euid(creds, &uid);
if (r < 0)
return r;
r = sd_bus_creds_get_pid(creds, &pid);
if (r < 0)
return r;
r = sd_bus_creds_get_cmdline(creds, &cmdline);
if (r < 0)
return r;
r = sd_bus_creds_get_comm(creds, &comm);
if (r < 0)
return r;
name = uid_to_name(uid);
if (!name)
return -ENOMEM;
p = strv_join(cmdline, " ");
if (!p)
return -ENOMEM;
/* The status string gets the full command line ... */
sd_notifyf(false,
"STATUS=Processing requests from client PID "PID_FMT" (%s); UID "UID_FMT" (%s)",
pid, p,
uid, name);
/* ... and the argv line only the short comm */
if (arg_command_line_buffer) {
size_t m, w;
m = strlen(arg_command_line_buffer);
w = snprintf(arg_command_line_buffer, m,
"[PID "PID_FMT"/%s; UID "UID_FMT"/%s]",
pid, comm,
uid, name);
if (m > w)
memzero(arg_command_line_buffer + w, m - w);
}
log_debug("Running on behalf of PID "PID_FMT" (%s), UID "UID_FMT" (%s), %s",
pid, p,
uid, name,
a->unique_name);
return 0;
}
int main(int argc, char *argv[]) {
_cleanup_(proxy_freep) Proxy *p = NULL;
int r;
log_set_target(LOG_TARGET_JOURNAL_OR_KMSG);
log_parse_environment();
log_open();
r = parse_argv(argc, argv);
if (r <= 0)
goto finish;
r = proxy_new(&p, STDIN_FILENO, STDOUT_FILENO, arg_address);
if (r < 0)
goto finish;
r = rename_service(p->destination_bus, p->local_bus);
if (r < 0)
log_debug_errno(r, "Failed to rename process: %m");
r = proxy_run(p);
finish:
sd_notify(false,
"STOPPING=1\n"
"STATUS=Shutting down.");
free(arg_address);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}