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main.c
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/* nbdkit
* Copyright Red Hat
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of Red Hat nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <getopt.h>
#include <limits.h>
#include <errno.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_LINUX_VM_SOCKETS_H
#include <linux/vm_sockets.h>
#elif HAVE_SYS_VSOCK_H
#include <sys/vsock.h>
#endif
#include <pthread.h>
#include <dlfcn.h>
#include "ascii-string.h"
#include "exit-with-parent.h"
#include "nbd-protocol.h"
#include "realpath.h"
#include "strndup.h"
#include "syslog.h"
#include "utils.h"
#include "internal.h"
#include "options.h"
#ifdef ENABLE_LIBFUZZER
#define main fuzzer_main
#endif
static char *make_random_fifo (void);
static struct backend *open_plugin_so (size_t i, const char *filename, int short_name);
static struct backend *open_filter_so (struct backend *next, size_t i, const char *filename, int short_name);
static void start_serving (void);
static void write_pidfile (void);
static bool is_config_key (const char *key, size_t len);
static void error_if_stdio_closed (void);
static void switch_stdio (void);
static void winsock_init (void);
int tcpip_sock_af = AF_UNSPEC; /* -4, -6 */
struct debug_flag *debug_flags; /* -D */
bool exit_with_parent; /* --exit-with-parent */
const char *export_name; /* -e */
bool foreground; /* -f */
const char *ipaddr; /* -i */
enum log_to log_to = LOG_TO_DEFAULT; /* --log */
unsigned mask_handshake = ~0U; /* --mask-handshake */
bool newstyle = true; /* false = -o, true = -n */
bool no_sr; /* --no-sr */
char *pidfile; /* -P */
const char *port; /* -p */
bool read_only; /* -r */
const char *run; /* --run */
bool listen_stdin; /* -s */
const char *selinux_label; /* --selinux-label */
bool swap; /* --swap */
unsigned threads; /* -t */
int tls; /* --tls : 0=off 1=on 2=require */
const char *tls_certificates_dir; /* --tls-certificates */
const char *tls_psk; /* --tls-psk */
bool tls_verify_peer; /* --tls-verify-peer */
char *unixsocket; /* -U */
const char *user, *group; /* -u & -g */
bool verbose; /* -v */
bool vsock; /* --vsock */
unsigned int socket_activation; /* $LISTEN_FDS and $LISTEN_PID set */
bool configured; /* .config_complete done */
int saved_stdin = -1; /* dup'd stdin during -s/--run */
int saved_stdout = -1; /* dup'd stdout during -s/--run */
/* The linked list of zero or more filters, and one plugin. */
struct backend *top;
static char *random_fifo_dir = NULL;
static char *random_fifo = NULL;
static void
usage (void)
{
/* --{short,long}-options remain undocumented */
const char *opt_list =
#include "synopsis.c"
;
printf ("%s\n", opt_list);
printf ("Please read the nbdkit(1) manual page for full usage.\n");
}
static void
display_version (void)
{
if (strcmp (NBDKIT_VERSION_EXTRA, "") == 0)
printf ("%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
else
printf ("%s %s (%s)\n",
PACKAGE_NAME, PACKAGE_VERSION, NBDKIT_VERSION_EXTRA);
}
static void
dump_config (void)
{
CLEANUP_FREE char *binary = NULL;
#ifdef __linux__
binary = realpath ("/proc/self/exe", NULL);
#else
#ifdef WIN32
/* GetModuleFileNameA has a crappy interface that prevents us from
* getting the length of the path so we just have to guess at an
* upper limit here. It will at least truncate it properly with \0.
* _get_pgmptr would be a better alternative except that it isn't
* implemented in MinGW. XXX
*/
binary = malloc (256);
if (!GetModuleFileNameA (NULL, binary, 256)) {
free (binary);
binary = NULL;
}
#endif
#endif
if (binary != NULL)
printf ("%s=%s\n", "binary", binary);
printf ("%s=%s\n", "bindir", bindir);
if (can_exit_with_parent ())
printf ("exit_with_parent=yes\n");
else
printf ("exit_with_parent=no\n");
printf ("%s=%s\n", "filterdir", filterdir);
printf ("%s=%s\n", "host_cpu", host_cpu);
printf ("%s=%s\n", "host_os", host_os);
printf ("%s=%s\n", "libdir", libdir);
printf ("%s=%s\n", "mandir", mandir);
printf ("%s=%s\n", "name", PACKAGE_NAME);
printf ("%s=%s\n", "plugindir", plugindir);
printf ("%s=%s\n", "root_tls_certificates_dir", root_tls_certificates_dir);
printf ("%s=%s\n", "sbindir", sbindir);
#ifdef HAVE_LIBSELINUX
printf ("selinux=yes\n");
#else
printf ("selinux=no\n");
#endif
printf ("%s=%s\n", "sysconfdir", sysconfdir);
#ifdef HAVE_GNUTLS
printf ("tls=yes\n");
#else
printf ("tls=no\n");
#endif
printf ("%s=%s\n", "version", PACKAGE_VERSION);
if (strcmp (NBDKIT_VERSION_EXTRA, "") != 0)
printf ("%s=%s\n", "version_extra", NBDKIT_VERSION_EXTRA);
printf ("%s=%d\n", "version_major", NBDKIT_VERSION_MAJOR);
printf ("%s=%d\n", "version_minor", NBDKIT_VERSION_MINOR);
#ifdef HAVE_LIBZSTD
printf ("zstd=yes\n");
#else
printf ("zstd=no\n");
#endif
}
int
main (int argc, char *argv[])
{
int c;
bool help = false, version = false, dump_plugin = false;
int tls_set_on_cli = false;
bool short_name;
const char *filename;
char *p;
static struct filter_filename {
struct filter_filename *next;
const char *filename;
} *filter_filenames = NULL;
size_t i;
const char *magic_config_key;
error_if_stdio_closed ();
winsock_init ();
#if !ENABLE_LIBFUZZER
threadlocal_init ();
#else
static bool main_called = false;
if (!main_called) {
threadlocal_init ();
main_called = true;
}
#endif
/* The default setting for TLS depends on whether we were
* compiled with GnuTLS.
*/
#ifdef HAVE_GNUTLS
tls = 1;
#else
tls = 0;
#endif
/* Returns 0 if no socket activation, or the number of FDs. */
socket_activation = get_socket_activation ();
for (;;) {
c = getopt_long (argc, argv, short_options, long_options, NULL);
if (c == -1)
break;
switch (c) {
case DUMP_CONFIG_OPTION:
dump_config ();
exit (EXIT_SUCCESS);
case DUMP_PLUGIN_OPTION:
dump_plugin = true;
break;
case EXIT_WITH_PARENT_OPTION:
if (can_exit_with_parent ()) {
exit_with_parent = true;
foreground = true;
}
else {
fprintf (stderr,
"%s: --exit-with-parent is not implemented "
"for this operating system\n",
program_name);
exit (EXIT_FAILURE);
}
break;
case FILTER_OPTION:
{
struct filter_filename *t;
t = malloc (sizeof *t);
if (t == NULL) {
perror ("malloc");
exit (EXIT_FAILURE);
}
t->next = filter_filenames;
t->filename = optarg;
filter_filenames = t;
}
break;
case LOG_OPTION:
if (strcmp (optarg, "stderr") == 0)
log_to = LOG_TO_STDERR;
else if (strcmp (optarg, "syslog") == 0)
log_to = LOG_TO_SYSLOG;
else if (strcmp (optarg, "null") == 0)
log_to = LOG_TO_NULL;
else {
fprintf (stderr, "%s: "
"--log must be \"stderr\", \"syslog\" or \"null\"\n",
program_name);
exit (EXIT_FAILURE);
}
break;
case LONG_OPTIONS_OPTION:
for (i = 0; long_options[i].name != NULL; ++i) {
if (strcmp (long_options[i].name, "long-options") != 0 &&
strcmp (long_options[i].name, "short-options") != 0)
printf ("--%s\n", long_options[i].name);
}
exit (EXIT_SUCCESS);
case RUN_OPTION:
if (socket_activation) {
fprintf (stderr, "%s: cannot use socket activation with --run flag\n",
program_name);
exit (EXIT_FAILURE);
}
run = optarg;
foreground = true;
break;
case SELINUX_LABEL_OPTION:
selinux_label = optarg;
break;
case SHORT_OPTIONS_OPTION:
for (i = 0; short_options[i]; ++i) {
if (short_options[i] != ':')
printf ("-%c\n", short_options[i]);
}
exit (EXIT_SUCCESS);
case SWAP_OPTION:
swap = 1;
break;
case TLS_OPTION:
tls_set_on_cli = true;
if (ascii_strcasecmp (optarg, "require") == 0 ||
ascii_strcasecmp (optarg, "required") == 0 ||
ascii_strcasecmp (optarg, "force") == 0)
tls = 2;
else {
tls = nbdkit_parse_bool (optarg);
if (tls == -1)
exit (EXIT_FAILURE);
}
break;
case TLS_CERTIFICATES_OPTION:
tls_certificates_dir = optarg;
break;
case TLS_PSK_OPTION:
tls_psk = optarg;
break;
case TLS_VERIFY_PEER_OPTION:
#ifdef HAVE_GNUTLS_SESSION_SET_VERIFY_CERT
tls_verify_peer = true;
#else
nbdkit_error ("--tls-verify-peer: "
"GnuTLS >= 3.4.6 is required for this feature");
exit (EXIT_FAILURE);
#endif
break;
case VSOCK_OPTION:
#if defined (AF_VSOCK) && defined (VMADDR_CID_ANY)
vsock = true;
break;
#else
fprintf (stderr, "%s: AF_VSOCK is not supported on this platform\n",
program_name);
exit (EXIT_FAILURE);
#endif
case '4':
tcpip_sock_af = AF_INET;
break;
case '6':
tcpip_sock_af = AF_INET6;
break;
case 'D':
add_debug_flag (optarg);
break;
case 'e':
export_name = optarg;
break;
case 'f':
foreground = true;
break;
case 'g':
group = optarg;
break;
case 'i':
if (socket_activation) {
fprintf (stderr, "%s: cannot use socket activation with -i flag\n",
program_name);
exit (EXIT_FAILURE);
}
ipaddr = optarg;
break;
case MASK_HANDSHAKE_OPTION:
if (nbdkit_parse_unsigned ("mask-handshake",
optarg, &mask_handshake) == -1)
exit (EXIT_FAILURE);
break;
case 'n':
newstyle = true;
break;
case NO_SR_OPTION:
no_sr = true;
break;
case 'o':
newstyle = false;
break;
case 'P':
pidfile = nbdkit_absolute_path (optarg);
if (pidfile == NULL)
exit (EXIT_FAILURE);
break;
case 'p':
if (socket_activation) {
fprintf (stderr, "%s: cannot use socket activation with -p flag\n",
program_name);
exit (EXIT_FAILURE);
}
port = optarg;
break;
case 'r':
read_only = true;
break;
case 's':
if (socket_activation) {
fprintf (stderr, "%s: cannot use socket activation with -s flag\n",
program_name);
exit (EXIT_FAILURE);
}
listen_stdin = true;
#ifdef WIN32
/* This could be implemented with a bit of work. The problem
* currently is that we try to use recv() on the stdio file
* descriptor which winsock does not support (nor Linux in
* fact). We would need to implement a test to see if the file
* descriptor is a socket or not and use either read or recv as
* appropriate.
*/
NOT_IMPLEMENTED_ON_WINDOWS ("-s");
#endif
break;
case 't':
if (nbdkit_parse_unsigned ("threads", optarg, &threads) == -1)
exit (EXIT_FAILURE);
/* XXX Worth a maximimum limit on threads? */
break;
case 'U':
if (socket_activation) {
fprintf (stderr, "%s: cannot use socket activation with -U flag\n",
program_name);
exit (EXIT_FAILURE);
}
if (strcmp (optarg, "-") == 0)
unixsocket = make_random_fifo ();
else
unixsocket = nbdkit_absolute_path (optarg);
if (unixsocket == NULL)
exit (EXIT_FAILURE);
break;
case 'u':
user = optarg;
break;
case 'v':
verbose = true;
break;
case 'V':
version = true;
break;
case HELP_OPTION:
help = true;
break;
default:
usage ();
exit (EXIT_FAILURE);
}
}
/* No extra parameters. */
if (optind >= argc) {
if (help) {
usage ();
exit (EXIT_SUCCESS);
}
if (version) {
display_version ();
exit (EXIT_SUCCESS);
}
if (dump_plugin) {
/* Incorrect use of --dump-plugin. */
fprintf (stderr,
"%s: use 'nbdkit plugin --dump-plugin' or\n"
"'nbdkit /path/to/plugin." SOEXT " --dump-plugin' or\n"
"if you want to find out about the server use --dump-config\n",
program_name);
exit (EXIT_FAILURE);
}
/* Otherwise this is an error. */
fprintf (stderr,
"%s: no plugins given on the command line.\n"
"Use '%s --help' or "
"read the nbdkit(1) manual page for documentation.\n",
program_name, program_name);
exit (EXIT_FAILURE);
}
/* --tls=require and oldstyle won't work. */
if (tls == 2 && !newstyle) {
fprintf (stderr,
"%s: cannot use oldstyle protocol (-o) and require TLS\n",
program_name);
exit (EXIT_FAILURE);
}
/* Set the umask to a known value. This makes the behaviour of
* plugins when creating files more predictable, and also removes an
* implicit dependency on umask when calling mkstemp(3).
*/
umask (0022);
/* If we will or might use syslog. */
if (log_to == LOG_TO_SYSLOG || log_to == LOG_TO_DEFAULT)
openlog (program_name, LOG_PID, 0);
/* Print the version in debug output, right after syslog initialization. */
if (strcmp (NBDKIT_VERSION_EXTRA, "") == 0)
debug ("%s %s", PACKAGE_NAME, PACKAGE_VERSION);
else
debug ("%s %s (%s)", PACKAGE_NAME, PACKAGE_VERSION, NBDKIT_VERSION_EXTRA);
/* Initialize TLS. */
crypto_init (tls_set_on_cli);
assert (tls != -1);
/* Implement --exit-with-parent early in case plugin initialization
* takes a long time and the parent exits during that time.
*/
if (set_exit_with_parent () == -1) {
perror ("nbdkit: --exit-with-parent");
exit (EXIT_FAILURE);
}
/* If the user has mixed up -p/--run/-s/-U/--vsock options, then
* give an error.
*
* XXX Actually the server could easily be extended to handle both
* TCP/IP and Unix sockets, or even multiple TCP/IP ports.
*/
if ((port && unixsocket) ||
(port && listen_stdin) ||
(unixsocket && listen_stdin) ||
(listen_stdin && run) ||
(listen_stdin && dump_plugin) ||
(vsock && unixsocket) ||
(vsock && listen_stdin)) {
fprintf (stderr,
"%s: --dump-plugin, -p, --run, -s, -U or --vsock options "
"cannot be used in this combination\n",
program_name);
exit (EXIT_FAILURE);
}
/* The remaining command line arguments are the plugin name and
* parameters. If --help, --version or --dump-plugin were specified
* then we open the plugin so that we can display the per-plugin
* help/version/plugin information.
*/
filename = argv[optind++];
short_name = is_short_name (filename);
/* Is there an executable script located in the plugindir?
* If so we simply execute it with the current command line.
*/
if (short_name) {
struct stat statbuf;
CLEANUP_FREE char *script;
if (asprintf (&script,
"%s/nbdkit-%s-plugin", plugindir, filename) == -1) {
perror ("asprintf");
exit (EXIT_FAILURE);
}
if (stat (script, &statbuf) == 0 &&
(statbuf.st_mode & S_IXUSR) != 0) {
/* We're going to execute the plugin directly.
* Replace argv[0] with argv[optind-1] and move further arguments
* down the list.
*/
argv[0] = argv[optind-1];
for (i = optind; i <= argc; i++)
argv[i-1] = argv[i];
execv (script, argv);
perror (script);
exit (EXIT_FAILURE);
}
}
/* Open the plugin (first) and then wrap the plugin with the
* filters. The filters are wrapped in reverse order that they
* appear on the command line so that in the end ‘top’ points to
* the first filter on the command line.
*/
top = open_plugin_so (0, filename, short_name);
i = 1;
while (filter_filenames) {
struct filter_filename *t = filter_filenames;
filename = t->filename;
short_name = is_short_name (filename);
top = open_filter_so (top, i++, filename, short_name);
filter_filenames = t->next;
free (t);
}
/* Apply nbdkit.* flags for the server. */
apply_debug_flags (RTLD_DEFAULT, "nbdkit");
/* Check all debug flags were used, and free them. */
free_debug_flags ();
if (help) {
struct backend *b;
usage ();
for_each_backend (b) {
printf ("\n");
b->usage (b);
}
top->free (top);
exit (EXIT_SUCCESS);
}
if (version) {
const char *v;
struct backend *b;
display_version ();
for_each_backend (b) {
printf ("%s", b->name);
if ((v = b->version (b)) != NULL)
printf (" %s", v);
printf ("\n");
}
top->free (top);
exit (EXIT_SUCCESS);
}
/* Call config and config_complete to parse the parameters.
*
* If the plugin provides magic_config_key then any "bare" values
* (ones not containing "=") are prefixed with this key.
*
* For backwards compatibility with old plugins, and to support
* scripting languages, if magic_config_key == NULL then if the
* first parameter is bare it is prefixed with the key "script", and
* any other bare parameters are errors.
*
* Keys must live for the life of nbdkit. Since we want to avoid
* modifying argv (so that /proc/PID/cmdline remains sane) but we
* need to create a key from argv[i] = "key=value" we must intern
* the keys, which are then freed at the end of main().
*/
magic_config_key = top->magic_config_key (top);
for (i = 0; optind < argc; ++i, ++optind) {
size_t n;
p = strchr (argv[optind], '=');
n = p - argv[optind];
if (p && is_config_key (argv[optind], n)) { /* Is it key=value? */
const char *key = nbdkit_strndup_intern (argv[optind], n);
if (key == NULL)
exit (EXIT_FAILURE);
top->config (top, key, p+1);
}
else if (magic_config_key == NULL) {
if (i == 0) /* magic script parameter */
top->config (top, "script", argv[optind]);
else {
fprintf (stderr,
"%s: expecting key=value on the command line but got: %s\n",
program_name, argv[optind]);
exit (EXIT_FAILURE);
}
}
else { /* magic config key */
top->config (top, magic_config_key, argv[optind]);
}
}
/* This must run after parsing the parameters so that the script can
* be loaded for scripting languages. But it must be called before
* config_complete so that the plugin doesn't check for missing
* parameters.
*/
if (dump_plugin) {
top->dump_fields (top);
top->free (top);
free_interns ();
exit (EXIT_SUCCESS);
}
top->config_complete (top);
/* Select the correct thread model based on config. */
lock_init_thread_model ();
/* Tell the plugin that we are about to start serving. This must be
* called before we change user, fork, or open any sockets.
*/
top->get_ready (top);
switch_stdio ();
configured = true;
start_serving ();
top->cleanup (top);
top->free (top);
top = NULL;
free (unixsocket);
free (pidfile);
if (random_fifo) {
unlink (random_fifo);
free (random_fifo);
}
if (random_fifo_dir) {
rmdir (random_fifo_dir);
free (random_fifo_dir);
}
crypto_free ();
close_quit_pipe ();
free_interns ();
/* Note: Don't exit here, otherwise this won't work when compiled
* for libFuzzer.
*/
return EXIT_SUCCESS;
}
/* Implementation of '-U -' */
static char *
make_random_fifo (void)
{
char *sock;
random_fifo_dir = make_temporary_directory ();
if (random_fifo_dir == NULL) {
perror ("make_temporary_directory");
return NULL;
}
if (asprintf (&random_fifo, "%s" DIR_SEPARATOR_STR "socket",
random_fifo_dir) == -1) {
perror ("asprintf");
goto error;
}
sock = strdup (random_fifo);
if (sock == NULL) {
perror ("strdup");
goto error;
}
return sock;
error:
free (random_fifo);
random_fifo = NULL;
rmdir (random_fifo_dir);
free (random_fifo_dir);
random_fifo_dir = NULL;
return NULL;
}
static struct backend *
open_plugin_so (size_t i, const char *name, int short_name)
{
struct backend *ret;
char *filename = (char *) name;
bool free_filename = false;
void *dl;
struct nbdkit_plugin *(*plugin_init) (void);
char *error;
if (short_name) {
/* Short names are rewritten relative to the plugindir. */
if (asprintf (&filename,
"%s/nbdkit-%s-plugin." SOEXT, plugindir, name) == -1) {
perror ("asprintf");
exit (EXIT_FAILURE);
}
free_filename = true;
}
dl = dlopen (filename, RTLD_NOW|RTLD_GLOBAL);
if (dl == NULL) {
fprintf (stderr,
"%s: error: cannot open plugin '%s': %s\n"
"Use '%s --help' or "
"read the nbdkit(1) manual page for documentation.\n",
program_name, name, dlerror (),
program_name);
exit (EXIT_FAILURE);
}
/* Initialize the plugin. See dlopen(3) to understand C weirdness. */
dlerror ();
plugin_init = dlsym (dl, "plugin_init");
if ((error = dlerror ()) != NULL) {
fprintf (stderr, "%s: %s: %s\n", program_name, name, error);
exit (EXIT_FAILURE);
}
if (!plugin_init) {
fprintf (stderr, "%s: %s: invalid plugin_init\n", program_name, name);
exit (EXIT_FAILURE);
}
/* Register the plugin. */
ret = plugin_register (i, filename, dl, plugin_init);
if (free_filename)
free (filename);
return ret;
}
static struct backend *
open_filter_so (struct backend *next, size_t i,
const char *name, int short_name)
{
struct backend *ret;
char *filename = (char *) name;
bool free_filename = false;
void *dl;
struct nbdkit_filter *(*filter_init) (void);
char *error;
if (short_name) {
/* Short names are rewritten relative to the filterdir. */
if (asprintf (&filename,
"%s/nbdkit-%s-filter." SOEXT, filterdir, name) == -1) {
perror ("asprintf");
exit (EXIT_FAILURE);
}
free_filename = true;
}
dl = dlopen (filename, RTLD_NOW|RTLD_GLOBAL);
if (dl == NULL) {
fprintf (stderr, "%s: error: cannot open filter '%s': %s\n",
program_name, name, dlerror ());
exit (EXIT_FAILURE);
}
/* Initialize the filter. See dlopen(3) to understand C weirdness. */
dlerror ();
filter_init = dlsym (dl, "filter_init");
if ((error = dlerror ()) != NULL) {
fprintf (stderr, "%s: %s: %s\n", program_name, name, error);
exit (EXIT_FAILURE);
}
if (!filter_init) {
fprintf (stderr, "%s: %s: invalid filter_init\n", program_name, name);
exit (EXIT_FAILURE);
}
/* Register the filter. */
ret = filter_register (next, i, filename, dl, filter_init);
if (free_filename)
free (filename);
return ret;
}
static void
start_serving (void)
{
sockets socks = empty_vector;
size_t i;
set_up_quit_pipe ();
#if !ENABLE_LIBFUZZER
set_up_signals ();
#endif
/* Lock the process into memory if requested. */
if (swap) {
#ifdef HAVE_MLOCKALL
if (mlockall (MCL_CURRENT | MCL_FUTURE) == -1) {
fprintf (stderr, "%s: --swap: mlockall: %m\n", program_name);
exit (EXIT_FAILURE);
}
debug ("mlockall done");
#else
fprintf (stderr, "%s: mlockall (--swap option) "
"is not supported on this platform\n", program_name);
exit (EXIT_FAILURE);
#endif
}
/* Socket activation: the ‘socket_activation’ variable (> 0) is the
* number of file descriptors from FIRST_SOCKET_ACTIVATION_FD to
* FIRST_SOCKET_ACTIVATION_FD+socket_activation-1.
*/
if (socket_activation) {
if (sockets_reserve (&socks, socket_activation) == -1) {
perror ("realloc");
exit (EXIT_FAILURE);
}
for (i = 0; i < socket_activation; ++i) {
int s = FIRST_SOCKET_ACTIVATION_FD + i, r;
/* This can't fail because of the reservation above. */
r = sockets_append (&socks, s);
assert (r == 0);
}
debug ("using socket activation, nr_socks = %zu", socks.len);
change_user ();
write_pidfile ();
top->after_fork (top);
accept_incoming_connections (&socks);
return;
}
/* Handling a single connection on stdin/stdout. */
if (listen_stdin) {
change_user ();
write_pidfile ();
top->after_fork (top);
threadlocal_new_server_thread ();
handle_single_connection (saved_stdin, saved_stdout);
return;
}
/* Handling multiple connections on TCP/IP, Unix domain socket or
* AF_VSOCK.
*/
if (unixsocket)
bind_unix_socket (&socks);
else if (vsock)
bind_vsock (&socks);
else
bind_tcpip_socket (&socks);
run_command ();
change_user ();
fork_into_background ();
write_pidfile ();
top->after_fork (top);
accept_incoming_connections (&socks);
}
static void
write_pidfile (void)
{