journald.c revision 260a2be45522f03ce8d8aca38e471d7b0882ff05
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2011 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/epoll.h>
#include <sys/socket.h>
#include <errno.h>
#include <sys/signalfd.h>
#include <unistd.h>
#include <fcntl.h>
#include "hashmap.h"
#include "journal-private.h"
#include "sd-daemon.h"
#include "socket-util.h"
typedef struct Server {
int syslog_fd;
int epoll_fd;
int signal_fd;
JournalFile *system_journal;
Hashmap *user_journals;
} Server;
static void process_message(Server *s, const char *buf, struct ucred *ucred, struct timeval *tv) {
char *message = NULL, *pid = NULL, *uid = NULL, *gid = NULL,
*source_time = NULL, *boot_id = NULL, *machine_id = NULL,
*comm = NULL, *cmdline = NULL, *hostname = NULL,
*audit_session = NULL, *audit_loginuid = NULL,
*syslog_priority = NULL, *syslog_facility = NULL,
*exe = NULL;
dual_timestamp ts;
struct iovec iovec[15];
unsigned n = 0;
char idbuf[33];
sd_id128_t id;
int r;
char *t;
int priority = LOG_USER | LOG_INFO;
dual_timestamp_get(&ts);
parse_syslog_priority((char**) &buf, &priority);
skip_syslog_date((char**) &buf);
if (asprintf(&syslog_priority, "PRIORITY=%i", priority & LOG_PRIMASK) >= 0)
IOVEC_SET_STRING(iovec[n++], syslog_priority);
if (asprintf(&syslog_facility, "SYSLOG_FACILITY=%i", LOG_FAC(priority)) >= 0)
IOVEC_SET_STRING(iovec[n++], syslog_facility);
message = strappend("MESSAGE=", buf);
if (message)
IOVEC_SET_STRING(iovec[n++], message);
if (ucred) {
uint32_t session;
uid_t loginuid;
if (asprintf(&pid, "PID=%lu", (unsigned long) ucred->pid) >= 0)
IOVEC_SET_STRING(iovec[n++], pid);
if (asprintf(&uid, "UID=%lu", (unsigned long) ucred->uid) >= 0)
IOVEC_SET_STRING(iovec[n++], uid);
if (asprintf(&gid, "GID=%lu", (unsigned long) ucred->gid) >= 0)
IOVEC_SET_STRING(iovec[n++], gid);
r = get_process_comm(ucred->pid, &t);
if (r >= 0) {
comm = strappend("COMM=", t);
if (comm)
IOVEC_SET_STRING(iovec[n++], comm);
free(t);
}
r = get_process_exe(ucred->pid, &t);
if (r >= 0) {
exe = strappend("EXE=", t);
if (comm)
IOVEC_SET_STRING(iovec[n++], exe);
free(t);
}
r = get_process_cmdline(ucred->pid, LINE_MAX, false, &t);
if (r >= 0) {
cmdline = strappend("CMDLINE=", t);
if (cmdline)
IOVEC_SET_STRING(iovec[n++], cmdline);
free(t);
}
r = audit_session_from_pid(ucred->pid, &session);
if (r >= 0)
if (asprintf(&audit_session, "AUDIT_SESSION=%lu", (unsigned long) session) >= 0)
IOVEC_SET_STRING(iovec[n++], audit_session);
r = audit_loginuid_from_pid(ucred->pid, &loginuid);
if (r >= 0)
if (asprintf(&audit_loginuid, "AUDIT_LOGINUID=%lu", (unsigned long) loginuid) >= 0)
IOVEC_SET_STRING(iovec[n++], audit_loginuid);
}
if (tv) {
if (asprintf(&source_time, "SOURCE_REALTIME_TIMESTAMP=%llu",
(unsigned long long) timeval_load(tv)) >= 0)
IOVEC_SET_STRING(iovec[n++], source_time);
}
r = sd_id128_get_boot(&id);
if (r >= 0)
if (asprintf(&boot_id, "BOOT_ID=%s", sd_id128_to_string(id, idbuf)) >= 0)
IOVEC_SET_STRING(iovec[n++], boot_id);
r = sd_id128_get_machine(&id);
if (r >= 0)
if (asprintf(&machine_id, "MACHINE_ID=%s", sd_id128_to_string(id, idbuf)) >= 0)
IOVEC_SET_STRING(iovec[n++], machine_id);
t = gethostname_malloc();
if (t) {
hostname = strappend("HOSTNAME=", t);
if (hostname)
IOVEC_SET_STRING(iovec[n++], hostname);
free(t);
}
r = journal_file_append_entry(s->system_journal, &ts, iovec, n, NULL, NULL);
if (r < 0)
log_error("Failed to write entry: %s", strerror(-r));
free(message);
free(pid);
free(uid);
free(gid);
free(comm);
free(cmdline);
free(source_time);
free(boot_id);
free(machine_id);
free(hostname);
free(audit_session);
free(audit_loginuid);
free(syslog_facility);
free(syslog_priority);
}
static int process_event(Server *s, struct epoll_event *ev) {
assert(s);
if (ev->events != EPOLLIN) {
log_info("Got invalid event from epoll.");
return -EIO;
}
if (ev->data.fd == s->signal_fd) {
struct signalfd_siginfo sfsi;
ssize_t n;
n = read(s->signal_fd, &sfsi, sizeof(sfsi));
if (n != sizeof(sfsi)) {
if (n >= 0)
return -EIO;
if (errno == EINTR || errno == EAGAIN)
return 0;
return -errno;
}
log_debug("Received SIG%s", signal_to_string(sfsi.ssi_signo));
return 0;
} else {
for (;;) {
char buf[LINE_MAX+1];
struct msghdr msghdr;
struct iovec iovec;
struct ucred *ucred = NULL;
struct timeval *tv = NULL;
struct cmsghdr *cmsg;
union {
struct cmsghdr cmsghdr;
uint8_t buf[CMSG_SPACE(sizeof(struct ucred)) +
CMSG_SPACE(sizeof(struct timeval))];
} control;
ssize_t n;
char *e;
zero(iovec);
iovec.iov_base = buf;
iovec.iov_len = sizeof(buf)-1;
zero(control);
zero(msghdr);
msghdr.msg_iov = &iovec;
msghdr.msg_iovlen = 1;
msghdr.msg_control = &control;
msghdr.msg_controllen = sizeof(control);
n = recvmsg(ev->data.fd, &msghdr, MSG_DONTWAIT);
if (n < 0) {
if (errno == EINTR || errno == EAGAIN)
return 1;
log_error("recvmsg() failed: %m");
return -errno;
}
for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_CREDENTIALS &&
cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred)))
ucred = (struct ucred*) CMSG_DATA(cmsg);
else if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SO_TIMESTAMP &&
cmsg->cmsg_len == CMSG_LEN(sizeof(struct timeval)))
tv = (struct timeval*) CMSG_DATA(cmsg);
}
e = memchr(buf, '\n', n);
if (e)
*e = 0;
else
buf[n] = 0;
process_message(s, strstrip(buf), ucred, tv);
}
}
return 1;
}
static int open_system_journal(JournalFile **f) {
int r;
r = journal_file_open("/var/log/journal/system.journal", O_RDWR|O_CREAT, 0644, f);
if (r == -ENOENT) {
mkdir_p("/run/log/journal", 0755);
r = journal_file_open("/run/log/journal/system.journal", O_RDWR|O_CREAT, 0644, f);
}
return r;
}
static int server_init(Server *s) {
int n, one, r;
struct epoll_event ev;
sigset_t mask;
assert(s);
zero(*s);
s->syslog_fd = s->signal_fd = -1;
s->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
if (s->epoll_fd < 0) {
log_error("Failed to create epoll object: %m");
return -errno;
}
n = sd_listen_fds(true);
if (n < 0) {
log_error("Failed to read listening file descriptors from environment: %s", strerror(-n));
return n;
}
if (n > 1) {
log_error("Too many file descriptors passed.");
return -EINVAL;
}
if (n == 1)
s->syslog_fd = SD_LISTEN_FDS_START;
else {
union sockaddr_union sa;
s->syslog_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
if (s->syslog_fd < 0) {
log_error("socket() failed: %m");
return -errno;
}
zero(sa);
sa.un.sun_family = AF_UNIX;
strncpy(sa.un.sun_path, "/run/systemd/syslog", sizeof(sa.un.sun_path));
unlink(sa.un.sun_path);
r = bind(s->syslog_fd, &sa.sa, sizeof(sa.un));
if (r < 0) {
log_error("bind() failed: %m");
return -errno;
}
chmod(sa.un.sun_path, 0666);
}
one = 1;
r = setsockopt(s->syslog_fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one));
if (r < 0) {
log_error("SO_PASSCRED failed: %m");
return -errno;
}
one = 1;
r = setsockopt(s->syslog_fd, SOL_SOCKET, SO_TIMESTAMP, &one, sizeof(one));
if (r < 0) {
log_error("SO_TIMESTAMP failed: %m");
return -errno;
}
zero(ev);
ev.events = EPOLLIN;
ev.data.fd = s->syslog_fd;
if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->syslog_fd, &ev) < 0) {
log_error("Failed to add server fd to epoll object: %m");
return -errno;
}
s->user_journals = hashmap_new(trivial_hash_func, trivial_compare_func);
if (!s->user_journals) {
log_error("Out of memory.");
return -ENOMEM;
}
r = open_system_journal(&s->system_journal);
if (r < 0) {
log_error("Failed to open journal: %s", strerror(-r));
return r;
}
assert_se(sigemptyset(&mask) == 0);
sigset_add_many(&mask, SIGINT, SIGTERM, -1);
assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
s->signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
if (s->signal_fd < 0) {
log_error("signalfd(): %m");
return -errno;
}
zero(ev);
ev.events = EPOLLIN;
ev.data.fd = s->signal_fd;
if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->signal_fd, &ev) < 0) {
log_error("epoll_ctl(): %m");
return -errno;
}
return 0;
}
static void server_done(Server *s) {
JournalFile *f;
assert(s);
if (s->system_journal)
journal_file_close(s->system_journal);
while ((f = hashmap_steal_first(s->user_journals)))
journal_file_close(f);
hashmap_free(s->user_journals);
if (s->epoll_fd >= 0)
close_nointr_nofail(s->epoll_fd);
if (s->signal_fd >= 0)
close_nointr_nofail(s->signal_fd);
if (s->syslog_fd >= 0)
close_nointr_nofail(s->syslog_fd);
}
int main(int argc, char *argv[]) {
Server server;
int r;
/* if (getppid() != 1) { */
/* log_error("This program should be invoked by init only."); */
/* return EXIT_FAILURE; */
/* } */
if (argc > 1) {
log_error("This program does not take arguments.");
return EXIT_FAILURE;
}
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
r = server_init(&server);
if (r < 0)
goto finish;
log_debug("systemd-journald running as pid %lu", (unsigned long) getpid());
sd_notify(false,
"READY=1\n"
"STATUS=Processing messages...");
for (;;) {
struct epoll_event event;
r = epoll_wait(server.epoll_fd, &event, 1, -1);
if (r < 0) {
if (errno == EINTR)
continue;
log_error("epoll_wait() failed: %m");
r = -errno;
goto finish;
} else if (r == 0)
break;
r = process_event(&server, &event);
if (r < 0)
goto finish;
else if (r == 0)
break;
}
finish:
sd_notify(false,
"STATUS=Shutting down...");
server_done(&server);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}