/*
* Copyright (c) 2015-19 David Lamparter, for NetDEF, Inc.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "zebra.h"
#include <sys/un.h>
#include <syslog.h>
#include "memory.h"
#include "frrcu.h"
#include "frr_pthread.h"
#include "printfrr.h"
#include "zlog.h"
#include "zlog_targets.h"
/* these allocations are intentionally left active even when doing full exit
* cleanup, in order to keep the logging subsystem fully functional until the
* absolute end.
*/
DECLARE_MGROUP(LOG)
DEFINE_MGROUP_ACTIVEATEXIT(LOG, "logging subsystem")
DEFINE_MTYPE_STATIC(LOG, LOG_FD, "log file target")
DEFINE_MTYPE_STATIC(LOG, LOG_FD_NAME, "log file name")
DEFINE_MTYPE_STATIC(LOG, LOG_FD_ROTATE, "log file rotate helper")
DEFINE_MTYPE_STATIC(LOG, LOG_SYSL, "syslog target")
struct zlt_fd {
struct zlog_target zt;
atomic_uint_fast32_t fd;
char ts_subsec;
bool record_priority;
struct rcu_head_close head_close;
};
static const char * const prionames[] = {
[LOG_EMERG] = "emergencies: ",
[LOG_ALERT] = "alerts: ",
[LOG_CRIT] = "critical: ",
[LOG_ERR] = "errors: ",
[LOG_WARNING] = "warnings: ",
[LOG_NOTICE] = "notifications: ",
[LOG_INFO] = "informational: ",
[LOG_DEBUG] = "debugging: ",
};
void zlog_fd(struct zlog_target *zt, struct zlog_msg *msgs[], size_t nmsgs)
{
struct zlt_fd *zte = container_of(zt, struct zlt_fd, zt);
int fd;
size_t i, textlen, iovpos = 0;
size_t niov = MIN(4 * nmsgs + 1, IOV_MAX);
struct iovec iov[niov];
/* "\nYYYY-MM-DD HH:MM:SS.NNNNNNNNN+ZZ:ZZ " = 37 chars */
#define TS_LEN 40
char ts_buf[TS_LEN * nmsgs], *ts_pos = ts_buf;
fd = atomic_load_explicit(&zte->fd, memory_order_relaxed);
for (i = 0; i < nmsgs; i++) {
struct zlog_msg *msg = msgs[i];
int prio = zlog_msg_prio(msg);
if (prio > zt->prio_min)
continue;
iov[iovpos].iov_base = ts_pos;
if (iovpos > 0)
*ts_pos++ = '\n';
ts_pos += zlog_msg_ts(msg, ts_pos, sizeof(ts_buf) - 1
- (ts_pos - ts_buf),
ZLOG_TS_LEGACY | zte->ts_subsec);
*ts_pos++ = ' ';
iov[iovpos].iov_len = ts_pos - (char *)iov[iovpos].iov_base;
iovpos++;
if (zte->record_priority) {
iov[iovpos].iov_base = (char *)prionames[prio];
iov[iovpos].iov_len = strlen(iov[iovpos].iov_base);
iovpos++;
}
iov[iovpos].iov_base = zlog_prefix;
iov[iovpos].iov_len = zlog_prefixsz;
iovpos++;
iov[iovpos].iov_base = (char *)zlog_msg_text(msg, &textlen);
iov[iovpos].iov_len = textlen;
iovpos++;
if (ts_buf + sizeof(ts_buf) - ts_pos < TS_LEN
|| i + 1 == nmsgs
|| array_size(iov) - iovpos < 5) {
iov[iovpos].iov_base = (char *)"\n";
iov[iovpos].iov_len = 1;
iovpos++;
writev(fd, iov, iovpos);
iovpos = 0;
ts_pos = ts_buf;
}
}
assert(iovpos == 0);
}
static void zlog_fd_sigsafe(struct zlog_target *zt, const char *text,
size_t len)
{
struct zlt_fd *zte = container_of(zt, struct zlt_fd, zt);
struct iovec iov[4];
int fd;
iov[0].iov_base = (char *)prionames[LOG_CRIT];
iov[0].iov_len = zte->record_priority ? strlen(iov[0].iov_base) : 0;
iov[1].iov_base = zlog_prefix;
iov[1].iov_len = zlog_prefixsz;
iov[2].iov_base = (char *)text;
iov[2].iov_len = len;
iov[3].iov_base = (char *)"\n";
iov[3].iov_len = 1;
fd = atomic_load_explicit(&zte->fd, memory_order_relaxed);
writev(fd, iov, array_size(iov));
}
/*
* (re-)configuration
*/
void zlog_file_init(struct zlog_cfg_file *zcf)
{
memset(zcf, 0, sizeof(*zcf));
zcf->prio_min = ZLOG_DISABLED;
zcf->fd = -1;
pthread_mutex_init(&zcf->cfg_mtx, NULL);
}
static void zlog_file_target_free(struct zlt_fd *zlt)
{
if (!zlt)
return;
rcu_close(&zlt->head_close, zlt->fd);
rcu_free(MTYPE_LOG_FD, zlt, zt.rcu_head);
}
void zlog_file_fini(struct zlog_cfg_file *zcf)
{
if (zcf->active) {
struct zlt_fd *ztf;
struct zlog_target *zt;
zt = zlog_target_replace(&zcf->active->zt, NULL);
ztf = container_of(zt, struct zlt_fd, zt);
zlog_file_target_free(ztf);
}
XFREE(MTYPE_LOG_FD_NAME, zcf->filename);
pthread_mutex_destroy(&zcf->cfg_mtx);
}
static bool zlog_file_cycle(struct zlog_cfg_file *zcf)
{
struct zlog_target *zt, *old;
struct zlt_fd *zlt = NULL;
int fd;
bool rv = true;
do {
if (zcf->prio_min == ZLOG_DISABLED)
break;
if (zcf->fd != -1)
fd = dup(zcf->fd);
else if (zcf->filename)
fd = open(zcf->filename,
O_WRONLY | O_APPEND | O_CREAT | O_CLOEXEC
| O_NOCTTY,
LOGFILE_MASK);
else
fd = -1;
if (fd < 0) {
rv = false;
break;
}
zt = zlog_target_clone(MTYPE_LOG_FD, &zcf->active->zt,
sizeof(*zlt));
zlt = container_of(zt, struct zlt_fd, zt);
zlt->fd = fd;
zlt->record_priority = zcf->record_priority;
zlt->ts_subsec = zcf->ts_subsec;
zlt->zt.prio_min = zcf->prio_min;
zlt->zt.logfn = zcf->zlog_wrap ? zcf->zlog_wrap : zlog_fd;
zlt->zt.logfn_sigsafe = zlog_fd_sigsafe;
} while (0);
old = zlog_target_replace(zcf->active ? &zcf->active->zt : NULL,
zlt ? &zlt->zt : NULL);
zcf->active = zlt;
zlog_file_target_free(container_of_null(old, struct zlt_fd, zt));
return rv;
}
void zlog_file_set_other(struct zlog_cfg_file *zcf)
{
frr_with_mutex(&zcf->cfg_mtx) {
zlog_file_cycle(zcf);
}
}
bool zlog_file_set_filename(struct zlog_cfg_file *zcf, const char *filename)
{
frr_with_mutex(&zcf->cfg_mtx) {
XFREE(MTYPE_LOG_FD_NAME, zcf->filename);
zcf->filename = XSTRDUP(MTYPE_LOG_FD_NAME, filename);
zcf->fd = -1;
return zlog_file_cycle(zcf);
}
assert(0);
}
bool zlog_file_set_fd(struct zlog_cfg_file *zcf, int fd)
{
frr_with_mutex(&zcf->cfg_mtx) {
if (zcf->fd == fd)
return true;
XFREE(MTYPE_LOG_FD_NAME, zcf->filename);
zcf->fd = fd;
return zlog_file_cycle(zcf);
}
assert(0);
}
struct rcu_close_rotate {
struct rcu_head_close head_close;
struct rcu_head head_self;
};
bool zlog_file_rotate(struct zlog_cfg_file *zcf)
{
struct rcu_close_rotate *rcr;
int fd;
frr_with_mutex(&zcf->cfg_mtx) {
if (!zcf->active || !zcf->filename)
return true;
fd = open(zcf->filename,
O_WRONLY | O_APPEND | O_CREAT | O_CLOEXEC | O_NOCTTY,
LOGFILE_MASK);
if (fd < 0)
return false;
fd = atomic_exchange_explicit(&zcf->active->fd,
(uint_fast32_t)fd,
memory_order_relaxed);
}
rcr = XCALLOC(MTYPE_LOG_FD_ROTATE, sizeof(*rcr));
rcu_close(&rcr->head_close, fd);
rcu_free(MTYPE_LOG_FD_ROTATE, rcr, head_self);
return true;
}
/* fixed crash logging */
static struct zlt_fd zlog_crashlog;
static void zlog_crashlog_sigsafe(struct zlog_target *zt, const char *text,
size_t len)
{
static int crashlog_fd = -1;
if (crashlog_fd == -1) {
#ifdef HAVE_OPENAT
crashlog_fd = openat(zlog_tmpdirfd, "crashlog",
O_WRONLY | O_APPEND | O_CREAT,
LOGFILE_MASK);
#endif
if (crashlog_fd < 0)
crashlog_fd = -2;
}
if (crashlog_fd == -2)
return;
zlog_crashlog.fd = crashlog_fd;
zlog_fd_sigsafe(&zlog_crashlog.zt, text, len);
}
/* this is used for assert failures (they don't need AS-Safe logging) */
static void zlog_crashlog_plain(struct zlog_target *zt, struct zlog_msg *msgs[],
size_t nmsgs)
{
size_t i, len;
const char *text;
for (i = 0; i < nmsgs; i++) {
if (zlog_msg_prio(msgs[i]) > zt->prio_min)
continue;
text = zlog_msg_text(msgs[i], &len);
zlog_crashlog_sigsafe(zt, text, len);
}
}
static void zlog_crashlog_init(void)
{
zlog_crashlog.zt.prio_min = LOG_CRIT;
zlog_crashlog.zt.logfn = zlog_crashlog_plain;
zlog_crashlog.zt.logfn_sigsafe = zlog_crashlog_sigsafe;
zlog_crashlog.fd = -1;
zlog_target_replace(NULL, &zlog_crashlog.zt);
}
/* fixed logging for test/auxiliary programs */
static struct zlt_fd zlog_aux_stdout;
static bool zlog_is_aux;
static int zlt_aux_init(const char *prefix, int prio_min)
{
zlog_is_aux = true;
zlog_aux_stdout.zt.prio_min = prio_min;
zlog_aux_stdout.zt.logfn = zlog_fd;
zlog_aux_stdout.zt.logfn_sigsafe = zlog_fd_sigsafe;
zlog_aux_stdout.fd = STDOUT_FILENO;
zlog_target_replace(NULL, &zlog_aux_stdout.zt);
zlog_startup_end();
return 0;
}
static int zlt_init(const char *progname, const char *protoname,
unsigned short instance, uid_t uid, gid_t gid)
{
openlog(progname, LOG_CONS | LOG_NDELAY | LOG_PID, LOG_DAEMON);
return 0;
}
static int zlt_fini(void)
{
closelog();
return 0;
}
/* fixed startup logging to stderr */
static struct zlt_fd zlog_startup_stderr;
__attribute__((_CONSTRUCTOR(450))) static void zlog_startup_init(void)
{
zlog_startup_stderr.zt.prio_min = LOG_WARNING;
zlog_startup_stderr.zt.logfn = zlog_fd;
zlog_startup_stderr.zt.logfn_sigsafe = zlog_fd_sigsafe;
zlog_startup_stderr.fd = STDERR_FILENO;
zlog_target_replace(NULL, &zlog_startup_stderr.zt);
hook_register(zlog_aux_init, zlt_aux_init);
hook_register(zlog_init, zlt_init);
hook_register(zlog_fini, zlt_fini);
}
void zlog_startup_end(void)
{
static bool startup_ended = false;
if (startup_ended)
return;
startup_ended = true;
zlog_target_replace(&zlog_startup_stderr.zt, NULL);
if (zlog_is_aux)
return;
/* until here, crashlogs go to stderr */
zlog_crashlog_init();
}
/* syslog */
struct zlt_syslog {
struct zlog_target zt;
int syslog_facility;
};
static void zlog_syslog(struct zlog_target *zt, struct zlog_msg *msgs[],
size_t nmsgs)
{
size_t i;
struct zlt_syslog *zte = container_of(zt, struct zlt_syslog, zt);
for (i = 0; i < nmsgs; i++) {
if (zlog_msg_prio(msgs[i]) > zt->prio_min)
continue;
syslog(zlog_msg_prio(msgs[i]) | zte->syslog_facility, "%s",
zlog_msg_text(msgs[i], NULL));
}
}
#ifndef _PATH_LOG
#define _PATH_LOG "/dev/log"
#endif
static void zlog_syslog_sigsafe(struct zlog_target *zt, const char *text,
size_t len)
{
static int syslog_fd = -1;
char hdr[192];
size_t hdrlen;
struct iovec iov[2];
if (syslog_fd == -1) {
syslog_fd = socket(AF_UNIX, SOCK_DGRAM, 0);
if (syslog_fd >= 0) {
struct sockaddr_un sa;
socklen_t salen = sizeof(sa);
sa.sun_family = AF_UNIX;
strlcpy(sa.sun_path, _PATH_LOG, sizeof(sa.sun_path));
#ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
salen = sa.sun_len = SUN_LEN(&sa);
#endif
if (connect(syslog_fd, (struct sockaddr *)&sa, salen)) {
close(syslog_fd);
syslog_fd = -1;
}
}
/* /dev/log could be a fifo instead of a socket */
if (syslog_fd == -1) {
syslog_fd = open(_PATH_LOG, O_WRONLY | O_NOCTTY);
if (syslog_fd < 0)
/* give up ... */
syslog_fd = -2;
}
}
if (syslog_fd == -2)
return;
/* note zlog_prefix includes trailing ": ", need to cut off 2 chars */
hdrlen = snprintfrr(hdr, sizeof(hdr), "<%d>%.*s[%ld]: ", LOG_CRIT,
zlog_prefixsz > 2 ? (int)(zlog_prefixsz - 2) : 0,
zlog_prefix, (long)getpid());
iov[0].iov_base = hdr;
iov[0].iov_len = hdrlen;
iov[1].iov_base = (char *)text;
iov[1].iov_len = len;
writev(syslog_fd, iov, array_size(iov));
}
static pthread_mutex_t syslog_cfg_mutex = PTHREAD_MUTEX_INITIALIZER;
static struct zlt_syslog *zlt_syslog;
static int syslog_facility = LOG_DAEMON;
static int syslog_prio_min = ZLOG_DISABLED;
void zlog_syslog_set_facility(int facility)
{
struct zlog_target *newztc;
struct zlt_syslog *newzt;
frr_with_mutex(&syslog_cfg_mutex) {
if (facility == syslog_facility)
return;
syslog_facility = facility;
if (syslog_prio_min == ZLOG_DISABLED)
return;
newztc = zlog_target_clone(MTYPE_LOG_SYSL, &zlt_syslog->zt,
sizeof(*newzt));
newzt = container_of(newztc, struct zlt_syslog, zt);
newzt->syslog_facility = syslog_facility;
zlog_target_free(MTYPE_LOG_SYSL,
zlog_target_replace(&zlt_syslog->zt,
&newzt->zt));
zlt_syslog = newzt;
}
}
int zlog_syslog_get_facility(void)
{
frr_with_mutex(&syslog_cfg_mutex) {
return syslog_facility;
}
assert(0);
}
void zlog_syslog_set_prio_min(int prio_min)
{
struct zlog_target *newztc;
struct zlt_syslog *newzt = NULL;
frr_with_mutex(&syslog_cfg_mutex) {
if (prio_min == syslog_prio_min)
return;
syslog_prio_min = prio_min;
if (syslog_prio_min != ZLOG_DISABLED) {
newztc = zlog_target_clone(MTYPE_LOG_SYSL,
&zlt_syslog->zt,
sizeof(*newzt));
newzt = container_of(newztc, struct zlt_syslog, zt);
newzt->zt.prio_min = prio_min;
newzt->zt.logfn = zlog_syslog;
newzt->zt.logfn_sigsafe = zlog_syslog_sigsafe;
newzt->syslog_facility = syslog_facility;
}
zlog_target_free(MTYPE_LOG_SYSL,
zlog_target_replace(&zlt_syslog->zt,
&newzt->zt));
zlt_syslog = newzt;
}
}
int zlog_syslog_get_prio_min(void)
{
frr_with_mutex(&syslog_cfg_mutex) {
return syslog_prio_min;
}
assert(0);
}