eudev/socket.c
2010-02-12 02:02:14 +01:00

848 lines
24 KiB
C

/*-*- Mode: C; c-basic-offset: 8 -*-*/
/***
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 General Public License as published by
the Free Software Foundation; either version 2 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
General Public License for more details.
You should have received a copy of the GNU General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/epoll.h>
#include <signal.h>
#include "unit.h"
#include "socket.h"
#include "log.h"
static const UnitActiveState state_translation_table[_SOCKET_STATE_MAX] = {
[SOCKET_DEAD] = UNIT_INACTIVE,
[SOCKET_START_PRE] = UNIT_ACTIVATING,
[SOCKET_START_POST] = UNIT_ACTIVATING,
[SOCKET_LISTENING] = UNIT_ACTIVE,
[SOCKET_RUNNING] = UNIT_ACTIVE,
[SOCKET_STOP_PRE] = UNIT_DEACTIVATING,
[SOCKET_STOP_PRE_SIGTERM] = UNIT_DEACTIVATING,
[SOCKET_STOP_PRE_SIGKILL] = UNIT_DEACTIVATING,
[SOCKET_STOP_POST] = UNIT_DEACTIVATING,
[SOCKET_STOP_POST_SIGTERM] = UNIT_DEACTIVATING,
[SOCKET_STOP_POST_SIGKILL] = UNIT_DEACTIVATING,
[SOCKET_MAINTAINANCE] = UNIT_INACTIVE,
};
static const char* const state_string_table[_SOCKET_STATE_MAX] = {
[SOCKET_DEAD] = "dead",
[SOCKET_START_PRE] = "start-pre",
[SOCKET_START_POST] = "start-post",
[SOCKET_LISTENING] = "listening",
[SOCKET_RUNNING] = "running",
[SOCKET_STOP_PRE] = "stop-pre",
[SOCKET_STOP_PRE_SIGTERM] = "stop-pre-sigterm",
[SOCKET_STOP_PRE_SIGKILL] = "stop-pre-sigkill",
[SOCKET_STOP_POST] = "stop-post",
[SOCKET_STOP_POST_SIGTERM] = "stop-post-sigterm",
[SOCKET_STOP_POST_SIGKILL] = "stop-post-sigkill",
[SOCKET_MAINTAINANCE] = "maintainance"
};
static void socket_done(Unit *u) {
Socket *s = SOCKET(u);
SocketPort *p;
assert(s);
while ((p = s->ports)) {
LIST_REMOVE(SocketPort, port, s->ports, p);
if (p->fd >= 0)
close_nointr(p->fd);
free(p->path);
free(p);
}
exec_context_done(&s->exec_context);
exec_command_free_array(s->exec_command, _SOCKET_EXEC_MAX);
s->control_command = NULL;
if (s->control_pid > 0) {
unit_unwatch_pid(u, s->control_pid);
s->control_pid = 0;
}
s->service = NULL;
free(s->bind_to_device);
unit_unwatch_timer(u, &s->timer_watch);
}
static int socket_init(Unit *u) {
Socket *s = SOCKET(u);
char *t;
int r;
/* First, reset everything to the defaults, in case this is a
* reload */
s->state = 0;
s->timer_watch.type = WATCH_INVALID;
s->bind_ipv6_only = false;
s->backlog = SOMAXCONN;
s->timeout_usec = DEFAULT_TIMEOUT_USEC;
s->directory_mode = 0755;
s->socket_mode = 0666;
exec_context_init(&s->exec_context);
if ((r = unit_load_fragment_and_dropin(u)) <= 0) {
if (r == 0)
r = -ENOENT;
goto fail;
}
if (!(t = unit_name_change_suffix(unit_id(u), ".service"))) {
r = -ENOMEM;
goto fail;
}
r = manager_load_unit(u->meta.manager, t, (Unit**) &s->service);
free(t);
if (r < 0)
goto fail;
if ((r = unit_add_dependency(u, UNIT_BEFORE, UNIT(s->service))) < 0)
goto fail;
return 0;
fail:
socket_done(u);
return r;
}
static const char* listen_lookup(int type) {
if (type == SOCK_STREAM)
return "ListenStream";
else if (type == SOCK_DGRAM)
return "ListenDatagram";
else if (type == SOCK_SEQPACKET)
return "ListenSequentialPacket";
assert_not_reached("Unknown socket type");
return NULL;
}
static void socket_dump(Unit *u, FILE *f, const char *prefix) {
static const char* const command_table[_SOCKET_EXEC_MAX] = {
[SOCKET_EXEC_START_PRE] = "StartPre",
[SOCKET_EXEC_START_POST] = "StartPost",
[SOCKET_EXEC_STOP_PRE] = "StopPre",
[SOCKET_EXEC_STOP_POST] = "StopPost"
};
SocketExecCommand c;
Socket *s = SOCKET(u);
SocketPort *p;
const char *prefix2;
char *p2;
assert(s);
assert(f);
p2 = strappend(prefix, "\t");
prefix2 = p2 ? p2 : prefix;
fprintf(f,
"%sSocket State: %s\n"
"%sBindIPv6Only: %s\n"
"%sBacklog: %u\n"
"%sSocketMode: %04o\n"
"%sDirectoryMode: %04o\n",
prefix, state_string_table[s->state],
prefix, yes_no(s->bind_ipv6_only),
prefix, s->backlog,
prefix, s->socket_mode,
prefix, s->directory_mode);
if (s->bind_to_device)
fprintf(f,
"%sBindToDevice: %s\n",
prefix, s->bind_to_device);
LIST_FOREACH(port, p, s->ports) {
if (p->type == SOCKET_SOCKET) {
const char *t;
int r;
char *k;
if ((r = socket_address_print(&p->address, &k)) < 0)
t = strerror(-r);
else
t = k;
fprintf(f, "%s%s: %s\n", prefix, listen_lookup(p->address.type), k);
free(k);
} else
fprintf(f, "%sListenFIFO: %s\n", prefix, p->path);
}
exec_context_dump(&s->exec_context, f, prefix);
for (c = 0; c < _SOCKET_EXEC_MAX; c++) {
if (!s->exec_command[c])
continue;
fprintf(f, "%s→ %s:\n",
prefix, command_table[c]);
exec_command_dump_list(s->exec_command[c], f, prefix2);
}
free(p2);
}
static void socket_close_fds(Socket *s) {
SocketPort *p;
assert(s);
LIST_FOREACH(port, p, s->ports) {
if (p->fd < 0)
continue;
unit_unwatch_fd(UNIT(s), &p->fd_watch);
assert_se(close_nointr(p->fd) >= 0);
p->fd = -1;
}
}
static int socket_open_fds(Socket *s) {
SocketPort *p;
int r;
assert(s);
LIST_FOREACH(port, p, s->ports) {
if (p->fd >= 0)
continue;
if (p->type == SOCKET_SOCKET) {
if ((r = socket_address_listen(
&p->address,
s->backlog,
s->bind_ipv6_only,
s->bind_to_device,
s->directory_mode,
s->socket_mode,
&p->fd)) < 0)
goto rollback;
} else {
struct stat st;
assert(p->type == SOCKET_FIFO);
if (mkfifo(p->path, 0666 & ~s->exec_context.umask) < 0 && errno != EEXIST) {
r = -errno;
goto rollback;
}
if ((p->fd = open(p->path, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK|O_NOFOLLOW)) < 0) {
r = -errno;
goto rollback;
}
if (fstat(p->fd, &st) < 0) {
r = -errno;
goto rollback;
}
/* FIXME verify user, access mode */
if (!S_ISFIFO(st.st_mode)) {
r = -EEXIST;
goto rollback;
}
}
}
return 0;
rollback:
socket_close_fds(s);
return r;
}
static void socket_unwatch_fds(Socket *s) {
SocketPort *p;
assert(s);
LIST_FOREACH(port, p, s->ports) {
if (p->fd < 0)
continue;
unit_unwatch_fd(UNIT(s), &p->fd_watch);
}
}
static int socket_watch_fds(Socket *s) {
SocketPort *p;
int r;
assert(s);
LIST_FOREACH(port, p, s->ports) {
if (p->fd < 0)
continue;
if ((r = unit_watch_fd(UNIT(s), p->fd, EPOLLIN, &p->fd_watch)) < 0)
goto fail;
}
return 0;
fail:
socket_unwatch_fds(s);
return r;
}
static void socket_set_state(Socket *s, SocketState state) {
SocketState old_state;
assert(s);
old_state = s->state;
s->state = state;
if (state != SOCKET_START_PRE &&
state != SOCKET_START_POST &&
state != SOCKET_STOP_PRE &&
state != SOCKET_STOP_PRE_SIGTERM &&
state != SOCKET_STOP_PRE_SIGKILL &&
state != SOCKET_STOP_POST &&
state != SOCKET_STOP_POST_SIGTERM &&
state != SOCKET_STOP_POST_SIGKILL)
unit_unwatch_timer(UNIT(s), &s->timer_watch);
if (state != SOCKET_START_PRE &&
state != SOCKET_START_POST &&
state != SOCKET_STOP_PRE &&
state != SOCKET_STOP_PRE_SIGTERM &&
state != SOCKET_STOP_PRE_SIGKILL &&
state != SOCKET_STOP_POST &&
state != SOCKET_STOP_POST_SIGTERM &&
state != SOCKET_STOP_POST_SIGKILL)
if (s->control_pid > 0) {
unit_unwatch_pid(UNIT(s), s->control_pid);
s->control_pid = 0;
}
if (state != SOCKET_START_PRE &&
state != SOCKET_START_POST &&
state != SOCKET_STOP_PRE &&
state != SOCKET_STOP_POST)
s->control_command = NULL;
if (state != SOCKET_START_POST &&
state != SOCKET_LISTENING &&
state != SOCKET_RUNNING &&
state != SOCKET_STOP_PRE &&
state != SOCKET_STOP_PRE_SIGTERM &&
state != SOCKET_STOP_PRE_SIGKILL)
socket_close_fds(s);
if (state != SOCKET_LISTENING)
socket_unwatch_fds(s);
log_debug("%s changed %s → %s", unit_id(UNIT(s)), state_string_table[old_state], state_string_table[state]);
unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state]);
}
static int socket_spawn(Socket *s, ExecCommand *c, bool timeout, pid_t *_pid) {
pid_t pid;
int r;
assert(s);
assert(c);
assert(_pid);
if (timeout) {
if ((r = unit_watch_timer(UNIT(s), s->timeout_usec, &s->timer_watch)) < 0)
goto fail;
} else
unit_unwatch_timer(UNIT(s), &s->timer_watch);
if ((r = exec_spawn(c, &s->exec_context, NULL, 0, &pid)) < 0)
goto fail;
if ((r = unit_watch_pid(UNIT(s), pid)) < 0)
/* FIXME: we need to do something here */
goto fail;
*_pid = pid;
return 0;
fail:
if (timeout)
unit_unwatch_timer(UNIT(s), &s->timer_watch);
return r;
}
static void socket_enter_dead(Socket *s, bool success) {
assert(s);
if (!success)
s->failure = true;
socket_set_state(s, s->failure ? SOCKET_MAINTAINANCE : SOCKET_DEAD);
}
static void socket_enter_stop_post(Socket *s, bool success) {
int r;
assert(s);
if (!success)
s->failure = true;
if ((s->control_command = s->exec_command[SOCKET_EXEC_STOP_POST]))
if ((r = socket_spawn(s, s->control_command, true, &s->control_pid)) < 0)
goto fail;
socket_set_state(s, SOCKET_STOP_POST);
if (!s->control_command)
socket_enter_dead(s, true);
return;
fail:
log_warning("%s failed to run stop-post executable: %s", unit_id(UNIT(s)), strerror(-r));
socket_enter_dead(s, false);
}
static void socket_enter_signal(Socket *s, SocketState state, bool success) {
int r;
assert(s);
if (!success)
s->failure = true;
if (s->control_pid > 0) {
int sig;
sig = (state == SOCKET_STOP_PRE_SIGTERM || state == SOCKET_STOP_POST_SIGTERM) ? SIGTERM : SIGKILL;
if (kill(s->control_pid, sig) < 0 && errno != ESRCH) {
r = -errno;
goto fail;
}
}
socket_set_state(s, state);
if (s->control_pid <= 0)
socket_enter_dead(s, true);
return;
fail:
log_warning("%s failed to kill processes: %s", unit_id(UNIT(s)), strerror(-r));
if (state == SOCKET_STOP_PRE_SIGTERM || state == SOCKET_STOP_PRE_SIGKILL)
socket_enter_stop_post(s, false);
else
socket_enter_dead(s, false);
}
static void socket_enter_stop_pre(Socket *s, bool success) {
int r;
assert(s);
if (!success)
s->failure = true;
if ((s->control_command = s->exec_command[SOCKET_EXEC_STOP_PRE]))
if ((r = socket_spawn(s, s->control_command, true, &s->control_pid)) < 0)
goto fail;
socket_set_state(s, SOCKET_STOP_PRE);
if (!s->control_command)
socket_enter_stop_post(s, true);
return;
fail:
log_warning("%s failed to run stop-pre executable: %s", unit_id(UNIT(s)), strerror(-r));
socket_enter_stop_post(s, false);
}
static void socket_enter_listening(Socket *s) {
int r;
assert(s);
if ((r = socket_watch_fds(s)) < 0) {
log_warning("%s failed to watch sockets: %s", unit_id(UNIT(s)), strerror(-r));
goto fail;
}
socket_set_state(s, SOCKET_LISTENING);
return;
fail:
socket_enter_stop_pre(s, false);
}
static void socket_enter_start_post(Socket *s) {
int r;
assert(s);
if ((r = socket_open_fds(s)) < 0) {
log_warning("%s failed to listen on sockets: %s", unit_id(UNIT(s)), strerror(-r));
goto fail;
}
if ((s->control_command = s->exec_command[SOCKET_EXEC_START_POST]))
if ((r = socket_spawn(s, s->control_command, true, &s->control_pid)) < 0) {
log_warning("%s failed to run start-post executable: %s", unit_id(UNIT(s)), strerror(-r));
goto fail;
}
socket_set_state(s, SOCKET_START_POST);
if (!s->control_command)
socket_enter_listening(s);
return;
fail:
socket_enter_stop_pre(s, false);
}
static void socket_enter_start_pre(Socket *s) {
int r;
assert(s);
if ((s->control_command = s->exec_command[SOCKET_EXEC_START_PRE]))
if ((r = socket_spawn(s, s->control_command, true, &s->control_pid)) < 0)
goto fail;
socket_set_state(s, SOCKET_START_PRE);
if (!s->control_command)
socket_enter_start_post(s);
return;
fail:
log_warning("%s failed to run start-pre exectuable: %s", unit_id(UNIT(s)), strerror(-r));
socket_enter_dead(s, false);
}
static void socket_enter_running(Socket *s) {
int r;
assert(s);
if ((r = manager_add_job(UNIT(s)->meta.manager, JOB_START, UNIT(s->service), JOB_REPLACE, true, NULL)) < 0)
goto fail;
socket_set_state(s, SOCKET_RUNNING);
return;
fail:
log_warning("%s failed to queue socket startup job: %s", unit_id(UNIT(s)), strerror(-r));
socket_enter_dead(s, false);
}
static void socket_run_next(Socket *s, bool success) {
int r;
assert(s);
assert(s->control_command);
assert(s->control_command->command_next);
if (!success)
s->failure = true;
s->control_command = s->control_command->command_next;
if ((r = socket_spawn(s, s->control_command, true, &s->control_pid)) < 0)
goto fail;
return;
fail:
if (s->state == SOCKET_STOP_PRE)
socket_enter_stop_post(s, false);
else if (s->state == SOCKET_STOP_POST)
socket_enter_dead(s, false);
else
socket_enter_stop_pre(s, false);
}
static int socket_start(Unit *u) {
Socket *s = SOCKET(u);
assert(s);
/* We cannot fulfill this request right now, try again later
* please! */
if (s->state == SOCKET_STOP_PRE ||
s->state == SOCKET_STOP_PRE_SIGKILL ||
s->state == SOCKET_STOP_PRE_SIGTERM ||
s->state == SOCKET_STOP_POST ||
s->state == SOCKET_STOP_POST_SIGTERM ||
s->state == SOCKET_STOP_POST_SIGKILL)
return -EAGAIN;
if (s->state == SOCKET_START_PRE ||
s->state == SOCKET_START_POST)
return 0;
/* Cannot run this without the service being around */
if (s->service->meta.load_state != UNIT_LOADED)
return -ENOENT;
assert(s->state == SOCKET_DEAD || s->state == SOCKET_MAINTAINANCE);
s->failure = false;
socket_enter_start_pre(s);
return 0;
}
static int socket_stop(Unit *u) {
Socket *s = SOCKET(u);
assert(s);
/* We cannot fulfill this request right now, try again later
* please! */
if (s->state == SOCKET_START_PRE ||
s->state == SOCKET_START_POST)
return -EAGAIN;
assert(s->state == SOCKET_LISTENING || s->state == SOCKET_RUNNING);
socket_enter_stop_pre(s, true);
return 0;
}
static UnitActiveState socket_active_state(Unit *u) {
assert(u);
return state_translation_table[SOCKET(u)->state];
}
static void socket_fd_event(Unit *u, int fd, uint32_t events, Watch *w) {
Socket *s = SOCKET(u);
assert(s);
log_debug("Incoming traffic on %s", unit_id(u));
if (events != EPOLLIN)
socket_enter_stop_pre(s, false);
socket_enter_running(s);
}
static void socket_sigchld_event(Unit *u, pid_t pid, int code, int status) {
Socket *s = SOCKET(u);
bool success;
assert(s);
assert(pid >= 0);
success = code == CLD_EXITED && status == 0;
s->failure = s->failure || !success;
assert(s->control_pid == pid);
assert(s->control_command);
exec_status_fill(&s->control_command->exec_status, pid, code, status);
s->control_pid = 0;
log_debug("%s control process exited, code=%s status=%i", unit_id(u), sigchld_code_to_string(code), status);
if (s->control_command->command_next &&
(success || (s->state == SOCKET_EXEC_STOP_PRE || s->state == SOCKET_EXEC_STOP_POST))) {
log_debug("%s running next command for the state %s", unit_id(u), state_string_table[s->state]);
socket_run_next(s, success);
} else {
/* No further commands for this step, so let's figure
* out what to do next */
log_debug("%s got final SIGCHLD for state %s", unit_id(u), state_string_table[s->state]);
switch (s->state) {
case SOCKET_START_PRE:
if (success)
socket_enter_start_post(s);
else
socket_enter_stop_pre(s, false);
break;
case SOCKET_START_POST:
if (success)
socket_enter_listening(s);
else
socket_enter_stop_pre(s, false);
break;
case SOCKET_STOP_PRE:
case SOCKET_STOP_PRE_SIGTERM:
case SOCKET_STOP_PRE_SIGKILL:
socket_enter_stop_post(s, success);
break;
case SOCKET_STOP_POST:
case SOCKET_STOP_POST_SIGTERM:
case SOCKET_STOP_POST_SIGKILL:
socket_enter_dead(s, success);
break;
default:
assert_not_reached("Uh, control process died at wrong time.");
}
}
}
static void socket_timer_event(Unit *u, uint64_t elapsed, Watch *w) {
Socket *s = SOCKET(u);
assert(s);
assert(elapsed == 1);
assert(w == &s->timer_watch);
switch (s->state) {
case SOCKET_START_PRE:
case SOCKET_START_POST:
log_warning("%s operation timed out. Stopping.", unit_id(u));
socket_enter_stop_pre(s, false);
break;
case SOCKET_STOP_PRE:
log_warning("%s stopping timed out. Terminating.", unit_id(u));
socket_enter_signal(s, SOCKET_STOP_PRE_SIGTERM, false);
break;
case SOCKET_STOP_PRE_SIGTERM:
log_warning("%s stopping timed out. Killing.", unit_id(u));
socket_enter_signal(s, SOCKET_STOP_PRE_SIGKILL, false);
break;
case SOCKET_STOP_PRE_SIGKILL:
log_warning("%s still around after SIGKILL. Ignoring.", unit_id(u));
socket_enter_stop_post(s, false);
break;
case SOCKET_STOP_POST:
log_warning("%s stopping timed out (2). Terminating.", unit_id(u));
socket_enter_signal(s, SOCKET_STOP_POST_SIGTERM, false);
break;
case SOCKET_STOP_POST_SIGTERM:
log_warning("%s stopping timed out (2). Killing.", unit_id(u));
socket_enter_signal(s, SOCKET_STOP_POST_SIGKILL, false);
break;
case SOCKET_STOP_POST_SIGKILL:
log_warning("%s still around after SIGKILL (2). Entering maintainance mode.", unit_id(u));
socket_enter_dead(s, false);
break;
default:
assert_not_reached("Timeout at wrong time.");
}
}
int socket_collect_fds(Socket *s, int **fds, unsigned *n_fds) {
int *rfds;
unsigned rn_fds, k;
SocketPort *p;
assert(s);
assert(fds);
assert(n_fds);
/* Called from the service code for requesting our fds */
rn_fds = 0;
LIST_FOREACH(port, p, s->ports)
if (p->fd >= 0)
rn_fds++;
if (!(rfds = new(int, rn_fds)) < 0)
return -ENOMEM;
k = 0;
LIST_FOREACH(port, p, s->ports)
if (p->fd >= 0)
rfds[k++] = p->fd;
assert(k == rn_fds);
*fds = rfds;
*n_fds = rn_fds;
return 0;
}
void socket_notify_service_dead(Socket *s) {
assert(s);
/* The service is dead. Dang. */
if (s->state == SOCKET_RUNNING) {
log_debug("%s got notified about service death.", unit_id(UNIT(s)));
socket_enter_listening(s);
}
}
const UnitVTable socket_vtable = {
.suffix = ".socket",
.init = socket_init,
.done = socket_done,
.dump = socket_dump,
.start = socket_start,
.stop = socket_stop,
.active_state = socket_active_state,
.fd_event = socket_fd_event,
.sigchld_event = socket_sigchld_event,
.timer_event = socket_timer_event
};