/*-*- 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/socket.h>
#include <sys/types.h>
#include <assert.h>
#include <sys/poll.h>
#include <sys/epoll.h>
#include <sys/un.h>
+#include <fcntl.h>
#include "util.h"
#include "log.h"
#include "list.h"
+#include "sd-daemon.h"
#define STREAM_BUFFER 2048
#define STREAMS_MAX 256
-#define SERVER_FD_START 3
#define SERVER_FD_MAX 16
#define TIMEOUT ((int) (10*MSEC_PER_SEC))
typedef struct Stream Stream;
typedef struct Server {
- int log_fd;
+ int syslog_fd;
+ int kmsg_fd;
int epoll_fd;
unsigned n_server_fd;
unsigned n_streams;
} Server;
+typedef enum StreamTarget {
+ STREAM_SYSLOG,
+ STREAM_KMSG
+} StreamTarget;
+
typedef enum StreamState {
+ STREAM_TARGET,
STREAM_PRIORITY,
STREAM_PROCESS,
+ STREAM_PREFIX,
STREAM_RUNNING
} StreamState;
StreamState state;
int fd;
+
+ LogTarget target;
int priority;
char *process;
+ pid_t pid;
+ uid_t uid;
+
+ bool prefix;
char buffer[STREAM_BUFFER];
size_t length;
- pid_t pid;
-
LIST_FIELDS(Stream, stream);
};
-#define IOVEC_SET_STRING(iovec, s) \
- do { \
- (iovec).iov_base = s; \
- (iovec).iov_len = strlen(s); \
- } while(false);
-
static int stream_log(Stream *s, char *p, usec_t timestamp) {
char header_priority[16], header_time[64], header_pid[16];
- time_t t;
- struct tm *tm;
- struct msghdr msghdr;
struct iovec iovec[5];
+ int priority;
assert(s);
assert(p);
+ priority = s->priority;
+
+ if (s->prefix &&
+ p[0] == '<' &&
+ p[1] >= '0' && p[1] <= '7' &&
+ p[2] == '>') {
+
+ /* Detected priority prefix */
+ priority = LOG_MAKEPRI(LOG_FAC(priority), (p[1] - '0'));
+
+ p += 3;
+ }
+
if (*p == 0)
return 0;
/*
- * The format glibc uses is:
+ * The format glibc uses to talk to the syslog daemon is:
+ *
+ * <priority>time process[pid]: msg
+ *
+ * The format the kernel uses is:
*
- * <priority>time process[pid]: msg
+ * <priority>msg\n
+ *
+ * We extend the latter to include the process name and pid.
*/
- snprintf(header_priority, sizeof(header_priority), "<%i>", s->priority);
+ snprintf(header_priority, sizeof(header_priority), "<%i>",
+ s->target == STREAM_SYSLOG ? priority : LOG_PRI(priority));
char_array_0(header_priority);
- t = (time_t) (timestamp / USEC_PER_SEC);
- if (!(tm = localtime(&t)))
- return -EINVAL;
+ if (s->target == STREAM_SYSLOG) {
+ time_t t;
+ struct tm *tm;
+
+ t = (time_t) (timestamp / USEC_PER_SEC);
+ if (!(tm = localtime(&t)))
+ return -EINVAL;
- if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
- return -EINVAL;
+ if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
+ return -EINVAL;
+ }
snprintf(header_pid, sizeof(header_pid), "[%llu]: ", (unsigned long long) s->pid);
char_array_0(header_pid);
zero(iovec);
IOVEC_SET_STRING(iovec[0], header_priority);
- IOVEC_SET_STRING(iovec[1], header_time);
- IOVEC_SET_STRING(iovec[2], s->process);
- IOVEC_SET_STRING(iovec[3], header_pid);
- IOVEC_SET_STRING(iovec[4], p);
- zero(msghdr);
- msghdr.msg_iov = iovec;
- msghdr.msg_iovlen = ELEMENTSOF(iovec);
+ if (s->target == STREAM_SYSLOG) {
+ struct msghdr msghdr;
- if (sendmsg(s->server->log_fd, &msghdr, MSG_NOSIGNAL) < 0)
- return -errno;
+ IOVEC_SET_STRING(iovec[1], header_time);
+ IOVEC_SET_STRING(iovec[2], s->process);
+ IOVEC_SET_STRING(iovec[3], header_pid);
+ IOVEC_SET_STRING(iovec[4], p);
+
+ zero(msghdr);
+ msghdr.msg_iov = iovec;
+ msghdr.msg_iovlen = ELEMENTSOF(iovec);
+
+ if (sendmsg(s->server->syslog_fd, &msghdr, MSG_NOSIGNAL) < 0)
+ return -errno;
+
+ } else if (s->target == STREAM_KMSG) {
+ IOVEC_SET_STRING(iovec[1], s->process);
+ IOVEC_SET_STRING(iovec[2], header_pid);
+ IOVEC_SET_STRING(iovec[3], p);
+ IOVEC_SET_STRING(iovec[4], (char*) "\n");
+
+ if (writev(s->server->kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
+ return -errno;
+ } else
+ assert_not_reached("Unknown log target");
return 0;
}
switch (s->state) {
+ case STREAM_TARGET:
+ if (streq(p, "syslog"))
+ s->target = STREAM_SYSLOG;
+ else if (streq(p, "kmsg")) {
+
+ if (s->server->kmsg_fd >= 0 && s->uid == 0)
+ s->target = STREAM_KMSG;
+ else {
+ log_warning("/dev/kmsg logging not available.");
+ return -EPERM;
+ }
+ } else {
+ log_warning("Failed to parse log target line.");
+ return -EBADMSG;
+ }
+ s->state = STREAM_PRIORITY;
+ return 0;
+
case STREAM_PRIORITY:
- if ((r = safe_atoi(p, &s->priority)) < 0)
+ if ((r = safe_atoi(p, &s->priority)) < 0) {
+ log_warning("Failed to parse log priority line: %s", strerror(errno));
return r;
+ }
- if (s->priority < 0)
+ if (s->priority < 0) {
+ log_warning("Log priority negative: %s", strerror(errno));
return -ERANGE;
+ }
s->state = STREAM_PROCESS;
return 0;
if (!(s->process = strdup(p)))
return -ENOMEM;
+ s->state = STREAM_PREFIX;
+ return 0;
+
+ case STREAM_PREFIX:
+
+ if ((r = parse_boolean(p)) < 0)
+ return r;
+
+ s->prefix = r;
s->state = STREAM_RUNNING;
return 0;
if (s->server)
epoll_ctl(s->server->epoll_fd, EPOLL_CTL_DEL, s->fd, NULL);
- assert_se(close_nointr(s->fd) == 0);
+ close_nointr_nofail(s->fd);
}
free(s->process);
if (s->n_streams >= STREAMS_MAX) {
log_warning("Too many connections, refusing connection.");
- assert_se(close_nointr(fd) == 0);
+ close_nointr_nofail(fd);
return 0;
}
if (!(stream = new0(Stream, 1))) {
- assert_se(close_nointr(fd) == 0);
+ close_nointr_nofail(fd);
return -ENOMEM;
}
zero(ev);
ev.data.ptr = stream;
- ev.events = POLLIN;
+ ev.events = EPOLLIN;
if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) {
r = -errno;
goto fail;
}
stream->pid = ucred.pid;
+ stream->uid = ucred.uid;
stream->server = s;
LIST_PREPEND(Stream, stream, s->streams, stream);
return r;
}
-static int verify_environment(unsigned *n_sockets) {
- unsigned long long pid;
- const char *e;
- int r;
- unsigned ns;
-
- assert_se(n_sockets);
-
- if (!(e = getenv("LISTEN_PID"))) {
- log_error("Missing $LISTEN_PID environment variable.");
- return -ENOENT;
- }
-
- if ((r = safe_atollu(e, &pid)) < 0) {
- log_error("Failed to parse $LISTEN_PID: %s", strerror(-r));
- return r;
- }
-
- if (pid != (unsigned long long) getpid()) {
- log_error("Socket nor for me.");
- return -ENOENT;
- }
-
- if (!(e = getenv("LISTEN_FDS"))) {
- log_error("Missing $LISTEN_FDS environment variable.");
- return -ENOENT;
- }
-
- if ((r = safe_atou(e, &ns)) < 0) {
- log_error("Failed to parse $LISTEN_FDS: %s", strerror(-r));
- return -E2BIG;
- }
-
- if (ns <= 0 || ns > SERVER_FD_MAX) {
- log_error("Wrong number of file descriptors passed: %s", e);
- return -E2BIG;
- }
-
- *n_sockets = ns;
-
- return 0;
-}
-
static void server_done(Server *s) {
unsigned i;
assert(s);
stream_free(s->streams);
for (i = 0; i < s->n_server_fd; i++)
- assert_se(close_nointr(SERVER_FD_START+i) == 0);
+ close_nointr_nofail(SD_LISTEN_FDS_START+i);
- if (s->log_fd >= 0)
- assert_se(close_nointr(s->log_fd) == 0);
+ if (s->syslog_fd >= 0)
+ close_nointr_nofail(s->syslog_fd);
if (s->epoll_fd >= 0)
- assert_se(close_nointr(s->epoll_fd) == 0);
+ close_nointr_nofail(s->epoll_fd);
+
+ if (s->kmsg_fd >= 0)
+ close_nointr_nofail(s->kmsg_fd);
}
static int server_init(Server *s, unsigned n_sockets) {
zero(*s);
s->n_server_fd = n_sockets;
- s->log_fd = -1;
+ s->syslog_fd = -1;
+ s->kmsg_fd = -1;
if ((s->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0) {
r = -errno;
struct epoll_event ev;
zero(ev);
- ev.events = POLLIN;
- ev.data.ptr = UINT_TO_PTR(SERVER_FD_START+i);
- if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, SERVER_FD_START+i, &ev) < 0) {
+ ev.events = EPOLLIN;
+ ev.data.ptr = UINT_TO_PTR(SD_LISTEN_FDS_START+i);
+ if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, SD_LISTEN_FDS_START+i, &ev) < 0) {
r = -errno;
log_error("Failed to add server fd to epoll object: %s", strerror(errno));
goto fail;
}
}
- if ((s->log_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) {
+ if ((s->syslog_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) {
r = -errno;
log_error("Failed to create log fd: %s", strerror(errno));
goto fail;
sa.un.sun_family = AF_UNIX;
strncpy(sa.un.sun_path, "/dev/log", sizeof(sa.un.sun_path));
- if (connect(s->log_fd, &sa.sa, sizeof(sa)) < 0) {
+ if (connect(s->syslog_fd, &sa.sa, sizeof(sa)) < 0) {
r = -errno;
log_error("Failed to connect log socket to /dev/log: %s", strerror(errno));
goto fail;
}
+ /* /dev/kmsg logging is strictly optional */
+ if ((s->kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0)
+ log_debug("Failed to open /dev/kmsg for logging, disabling kernel log buffer support: %s", strerror(errno));
+
return 0;
fail:
assert(s);
/* Yes, this is a bit ugly, we assume that that valid pointers
- * are > SERVER_FD_START+SERVER_FD_MAX. Which is certainly
+ * are > SD_LISTEN_FDS_START+SERVER_FD_MAX. Which is certainly
* true on Linux (and probably most other OSes, too, since the
* first 4k usually are part of a seperate null pointer
* dereference page. */
- if (PTR_TO_UINT(ev->data.ptr) >= SERVER_FD_START &&
- PTR_TO_UINT(ev->data.ptr) < SERVER_FD_START+s->n_server_fd) {
+ if (PTR_TO_UINT(ev->data.ptr) >= SD_LISTEN_FDS_START &&
+ PTR_TO_UINT(ev->data.ptr) < SD_LISTEN_FDS_START+s->n_server_fd) {
- if (ev->events != POLLIN) {
+ if (ev->events != EPOLLIN) {
log_info("Got invalid event from epoll. (1)");
return -EIO;
}
timestamp = now(CLOCK_REALTIME);
- if (!(ev->events & POLLIN)) {
- log_info("Got invalid event from epoll. (3)");
+ if (!(ev->events & EPOLLIN)) {
+ log_info("Got invalid event from epoll. (2)");
stream_free(stream);
return 0;
}
int main(int argc, char *argv[]) {
Server server;
- int r = 3;
- unsigned n;
+ int r = 3, n;
+
+ log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
+ log_parse_environment();
log_info("systemd-logger running as pid %llu", (unsigned long long) getpid());
- if (verify_environment(&n) < 0)
+ if ((n = sd_listen_fds(true)) < 0) {
+ log_error("Failed to read listening file descriptors from environment: %s", strerror(-r));
return 1;
+ }
- if (server_init(&server, n) < 0)
+ if (n <= 0 || n > SERVER_FD_MAX) {
+ log_error("No or too many file descriptors passed.");
return 2;
+ }
+ if (server_init(&server, (unsigned) n) < 0)
+ return 3;
for (;;) {
struct epoll_event event;
- int n;
+ int k;
- if ((n = epoll_wait(server.epoll_fd,
+ if ((k = epoll_wait(server.epoll_fd,
&event, 1,
server.n_streams <= 0 ? TIMEOUT : -1)) < 0) {
goto fail;
}
- if (n <= 0)
+ if (k <= 0)
break;
- if ((r = process_event(&server, &event)) < 0)
+ if ((k = process_event(&server, &event)) < 0)
goto fail;
}
r = 0;