journald.c revision babfc09177c1e71cec6c1ef9602e265ed40cfe4f
/*-*- 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 <sys/acl.h>
#include <acl/libacl.h>
#include <stddef.h>
#include <sys/ioctl.h>
#include <linux/sockios.h>
#include <sys/statvfs.h>
#include "hashmap.h"
#include "journal-file.h"
#include "sd-daemon.h"
#include "socket-util.h"
#include "acl-util.h"
#include "cgroup-util.h"
#include "list.h"
#include "journal-rate-limit.h"
#include "sd-journal.h"
#include "journal-internal.h"
#define USER_JOURNALS_MAX 1024
#define STDOUT_STREAMS_MAX 4096
#define DEFAULT_RATE_LIMIT_INTERVAL (10*USEC_PER_SEC)
#define DEFAULT_RATE_LIMIT_BURST 200
#define RECHECK_AVAILABLE_SPACE_USEC (30*USEC_PER_SEC)
#define RECHECK_VAR_AVAILABLE_USEC (30*USEC_PER_SEC)
#define SYSLOG_TIMEOUT_USEC (5*USEC_PER_SEC)
typedef struct StdoutStream StdoutStream;
typedef struct Server {
int epoll_fd;
int signal_fd;
int syslog_fd;
int native_fd;
int stdout_fd;
JournalFile *runtime_journal;
JournalFile *system_journal;
Hashmap *user_journals;
uint64_t seqnum;
char *buffer;
size_t buffer_size;
JournalRateLimit *rate_limit;
JournalMetrics runtime_metrics;
JournalMetrics system_metrics;
bool compress;
uint64_t cached_available_space;
usec_t cached_available_space_timestamp;
uint64_t var_available_timestamp;
LIST_HEAD(StdoutStream, stdout_streams);
unsigned n_stdout_streams;
} Server;
typedef enum StdoutStreamState {
STDOUT_STREAM_TAG,
STDOUT_STREAM_PRIORITY,
STDOUT_STREAM_PRIORITY_PREFIX,
STDOUT_STREAM_TEE_CONSOLE,
STDOUT_STREAM_RUNNING
} StdoutStreamState;
struct StdoutStream {
Server *server;
StdoutStreamState state;
int fd;
struct ucred ucred;
char *tag;
int priority;
bool priority_prefix:1;
bool tee_console:1;
char buffer[LINE_MAX+1];
size_t length;
LIST_FIELDS(StdoutStream, stdout_stream);
};
static int server_flush_to_var(Server *s);
static uint64_t available_space(Server *s) {
char ids[33], *p;
const char *f;
sd_id128_t machine;
struct statvfs ss;
uint64_t sum = 0, avail = 0, ss_avail = 0;
int r;
DIR *d;
usec_t ts;
JournalMetrics *m;
ts = now(CLOCK_MONOTONIC);
if (s->cached_available_space_timestamp + RECHECK_AVAILABLE_SPACE_USEC > ts)
return s->cached_available_space;
r = sd_id128_get_machine(&machine);
if (r < 0)
return 0;
if (s->system_journal) {
f = "/var/log/journal/";
m = &s->system_metrics;
} else {
f = "/run/log/journal/";
m = &s->runtime_metrics;
}
assert(m);
p = strappend(f, sd_id128_to_string(machine, ids));
if (!p)
return 0;
d = opendir(p);
free(p);
if (!d)
return 0;
if (fstatvfs(dirfd(d), &ss) < 0)
goto finish;
for (;;) {
struct stat st;
struct dirent buf, *de;
int k;
k = readdir_r(d, &buf, &de);
if (k != 0) {
r = -k;
goto finish;
}
if (!de)
break;
if (!dirent_is_file_with_suffix(de, ".journal"))
continue;
if (fstatat(dirfd(d), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0)
continue;
sum += (uint64_t) st.st_blocks * (uint64_t) st.st_blksize;
}
avail = sum >= m->max_use ? 0 : m->max_use - sum;
ss_avail = ss.f_bsize * ss.f_bavail;
ss_avail = ss_avail < m->keep_free ? 0 : ss_avail - m->keep_free;
if (ss_avail < avail)
avail = ss_avail;
s->cached_available_space = avail;
s->cached_available_space_timestamp = ts;
finish:
closedir(d);
return avail;
}
static void fix_perms(JournalFile *f, uid_t uid) {
acl_t acl;
acl_entry_t entry;
acl_permset_t permset;
int r;
assert(f);
r = fchmod_and_fchown(f->fd, 0640, 0, 0);
if (r < 0)
log_warning("Failed to fix access mode/rights on %s, ignoring: %s", f->path, strerror(-r));
if (uid <= 0)
return;
acl = acl_get_fd(f->fd);
if (!acl) {
log_warning("Failed to read ACL on %s, ignoring: %m", f->path);
return;
}
r = acl_find_uid(acl, uid, &entry);
if (r <= 0) {
if (acl_create_entry(&acl, &entry) < 0 ||
acl_set_tag_type(entry, ACL_USER) < 0 ||
acl_set_qualifier(entry, &uid) < 0) {
log_warning("Failed to patch ACL on %s, ignoring: %m", f->path);
goto finish;
}
}
if (acl_get_permset(entry, &permset) < 0 ||
acl_add_perm(permset, ACL_READ) < 0 ||
acl_calc_mask(&acl) < 0) {
log_warning("Failed to patch ACL on %s, ignoring: %m", f->path);
goto finish;
}
if (acl_set_fd(f->fd, acl) < 0)
log_warning("Failed to set ACL on %s, ignoring: %m", f->path);
finish:
acl_free(acl);
}
static JournalFile* find_journal(Server *s, uid_t uid) {
char *p;
int r;
JournalFile *f;
char ids[33];
sd_id128_t machine;
assert(s);
/* We split up user logs only on /var, not on /run. If the
* runtime file is open, we write to it exclusively, in order
* to guarantee proper order as soon as we flush /run to
* /var and close the runtime file. */
if (s->runtime_journal)
return s->runtime_journal;
if (uid <= 0)
return s->system_journal;
r = sd_id128_get_machine(&machine);
if (r < 0)
return s->system_journal;
f = hashmap_get(s->user_journals, UINT32_TO_PTR(uid));
if (f)
return f;
if (asprintf(&p, "/var/log/journal/%s/user-%lu.journal", sd_id128_to_string(machine, ids), (unsigned long) uid) < 0)
return s->system_journal;
while (hashmap_size(s->user_journals) >= USER_JOURNALS_MAX) {
/* Too many open? Then let's close one */
f = hashmap_steal_first(s->user_journals);
assert(f);
journal_file_close(f);
}
r = journal_file_open(p, O_RDWR|O_CREAT, 0640, s->system_journal, &f);
free(p);
if (r < 0)
return s->system_journal;
fix_perms(f, uid);
f->metrics = s->system_metrics;
f->compress = s->compress;
r = hashmap_put(s->user_journals, UINT32_TO_PTR(uid), f);
if (r < 0) {
journal_file_close(f);
return s->system_journal;
}
return f;
}
static void server_vacuum(Server *s) {
Iterator i;
void *k;
char *p;
char ids[33];
sd_id128_t machine;
int r;
JournalFile *f;
log_info("Rotating...");
if (s->runtime_journal) {
r = journal_file_rotate(&s->runtime_journal);
if (r < 0)
log_error("Failed to rotate %s: %s", s->runtime_journal->path, strerror(-r));
}
if (s->system_journal) {
r = journal_file_rotate(&s->system_journal);
if (r < 0)
log_error("Failed to rotate %s: %s", s->system_journal->path, strerror(-r));
}
HASHMAP_FOREACH_KEY(f, k, s->user_journals, i) {
r = journal_file_rotate(&f);
if (r < 0)
log_error("Failed to rotate %s: %s", f->path, strerror(-r));
else
hashmap_replace(s->user_journals, k, f);
}
log_info("Vacuuming...");
r = sd_id128_get_machine(&machine);
if (r < 0) {
log_error("Failed to get machine ID: %s", strerror(-r));
return;
}
sd_id128_to_string(machine, ids);
if (s->system_journal) {
if (asprintf(&p, "/var/log/journal/%s", ids) < 0) {
log_error("Out of memory.");
return;
}
r = journal_directory_vacuum(p, s->system_metrics.max_use, s->system_metrics.keep_free);
if (r < 0 && r != -ENOENT)
log_error("Failed to vacuum %s: %s", p, strerror(-r));
free(p);
}
if (s->runtime_journal) {
if (asprintf(&p, "/run/log/journal/%s", ids) < 0) {
log_error("Out of memory.");
return;
}
r = journal_directory_vacuum(p, s->runtime_metrics.max_use, s->runtime_metrics.keep_free);
if (r < 0 && r != -ENOENT)
log_error("Failed to vacuum %s: %s", p, strerror(-r));
free(p);
}
s->cached_available_space_timestamp = 0;
}
static char *shortened_cgroup_path(pid_t pid) {
int r;
char *process_path, *init_path, *path;
assert(pid > 0);
r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, pid, &process_path);
if (r < 0)
return NULL;
r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 1, &init_path);
if (r < 0) {
free(process_path);
return NULL;
}
if (streq(init_path, "/"))
init_path[0] = 0;
if (startswith(process_path, init_path)) {
char *p;
p = strdup(process_path + strlen(init_path));
if (!p) {
free(process_path);
free(init_path);
return NULL;
}
path = p;
} else {
path = process_path;
process_path = NULL;
}
free(process_path);
free(init_path);
return path;
}
static void dispatch_message_real(Server *s,
struct iovec *iovec, unsigned n, unsigned m,
struct ucred *ucred,
struct timeval *tv) {
char *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,
*exe = NULL, *cgroup = NULL;
char idbuf[33];
sd_id128_t id;
int r;
char *t;
uid_t loginuid = 0, realuid = 0;
JournalFile *f;
bool vacuumed = false;
assert(s);
assert(iovec);
assert(n > 0);
assert(n + 13 <= m);
if (ucred) {
uint32_t session;
char *path;
realuid = ucred->uid;
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);
path = shortened_cgroup_path(ucred->pid);
if (path) {
cgroup = strappend("_SYSTEMD_CGROUP=", path);
if (cgroup)
IOVEC_SET_STRING(iovec[n++], cgroup);
free(path);
}
}
if (tv) {
if (asprintf(&source_time, "_SOURCE_REALTIME_TIMESTAMP=%llu",
(unsigned long long) timeval_load(tv)) >= 0)
IOVEC_SET_STRING(iovec[n++], source_time);
}
/* Note that strictly speaking storing the boot id here is
* redundant since the entry includes this in-line
* anyway. However, we need this indexed, too. */
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);
}
assert(n <= m);
server_flush_to_var(s);
retry:
f = find_journal(s, realuid == 0 ? 0 : loginuid);
if (!f)
log_warning("Dropping message, as we can't find a place to store the data.");
else {
r = journal_file_append_entry(f, NULL, iovec, n, &s->seqnum, NULL, NULL);
if (r == -E2BIG && !vacuumed) {
log_info("Allocation limit reached.");
server_vacuum(s);
vacuumed = true;
log_info("Retrying write.");
goto retry;
}
if (r < 0)
log_error("Failed to write entry, ignoring: %s", strerror(-r));
}
free(pid);
free(uid);
free(gid);
free(comm);
free(exe);
free(cmdline);
free(source_time);
free(boot_id);
free(machine_id);
free(hostname);
free(audit_session);
free(audit_loginuid);
free(cgroup);
}
static void dispatch_message(Server *s,
struct iovec *iovec, unsigned n, unsigned m,
struct ucred *ucred,
struct timeval *tv,
int priority) {
int rl;
char *path = NULL, *c;
assert(s);
assert(iovec || n == 0);
if (n == 0)
return;
if (!ucred)
goto finish;
path = shortened_cgroup_path(ucred->pid);
if (!path)
goto finish;
/* example: /user/lennart/3/foobar
* /system/dbus.service/foobar
*
* So let's cut of everything past the third /, since that is
* wher user directories start */
c = strchr(path, '/');
if (c) {
c = strchr(c+1, '/');
if (c) {
c = strchr(c+1, '/');
if (c)
*c = 0;
}
}
rl = journal_rate_limit_test(s->rate_limit, path, priority, available_space(s));
if (rl == 0) {
free(path);
return;
}
if (rl > 1) {
int j = 0;
char suppress_message[LINE_MAX];
struct iovec suppress_iovec[15];
/* Write a suppression message if we suppressed something */
snprintf(suppress_message, sizeof(suppress_message), "MESSAGE=Suppressed %u messages from %s", rl - 1, path);
char_array_0(suppress_message);
IOVEC_SET_STRING(suppress_iovec[j++], "PRIORITY=5");
IOVEC_SET_STRING(suppress_iovec[j++], suppress_message);
dispatch_message_real(s, suppress_iovec, j, ELEMENTSOF(suppress_iovec), NULL, NULL);
}
free(path);
finish:
dispatch_message_real(s, iovec, n, m, ucred, tv);
}
static void process_syslog_message(Server *s, const char *buf, struct ucred *ucred, struct timeval *tv) {
char *message = NULL, *syslog_priority = NULL, *syslog_facility = NULL;
struct iovec iovec[16];
unsigned n = 0;
int priority = LOG_USER | LOG_INFO;
assert(s);
assert(buf);
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);
dispatch_message(s, iovec, n, ELEMENTSOF(iovec), ucred, tv, priority & LOG_PRIMASK);
free(message);
free(syslog_facility);
free(syslog_priority);
}
static bool valid_user_field(const char *p, size_t l) {
const char *a;
/* We kinda enforce POSIX syntax recommendations for
environment variables here, but make a couple of additional
requirements.
http://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap08.html */
/* No empty field names */
if (l <= 0)
return false;
/* Don't allow names longer than 64 chars */
if (l > 64)
return false;
/* Variables starting with an underscore are protected */
if (p[0] == '_')
return false;
/* Don't allow digits as first character */
if (p[0] >= '0' && p[0] <= '9')
return false;
/* Only allow A-Z0-9 and '_' */
for (a = p; a < p + l; a++)
if (!((*a >= 'A' && *a <= 'Z') ||
(*a >= '0' && *a <= '9') ||
*a == '_'))
return false;
return true;
}
static void process_native_message(Server *s, const void *buffer, size_t buffer_size, struct ucred *ucred, struct timeval *tv) {
struct iovec *iovec = NULL;
unsigned n = 0, m = 0, j;
const char *p;
size_t remaining;
int priority = LOG_INFO;
assert(s);
assert(buffer || n == 0);
p = buffer;
remaining = buffer_size;
while (remaining > 0) {
const char *e, *q;
e = memchr(p, '\n', remaining);
if (!e) {
/* Trailing noise, let's ignore it, and flush what we collected */
log_debug("Received message with trailing noise, ignoring.");
break;
}
if (e == p) {
/* Entry separator */
dispatch_message(s, iovec, n, m, ucred, tv, priority);
n = 0;
priority = LOG_INFO;
p++;
remaining--;
continue;
}
if (*p == '.' || *p == '#') {
/* Ignore control commands for now, and
* comments too. */
remaining -= (e - p) + 1;
p = e + 1;
continue;
}
/* A property follows */
if (n+13 >= m) {
struct iovec *c;
unsigned u;
u = MAX((n+13U) * 2U, 4U);
c = realloc(iovec, u * sizeof(struct iovec));
if (!c) {
log_error("Out of memory");
break;
}
iovec = c;
m = u;
}
q = memchr(p, '=', e - p);
if (q) {
if (valid_user_field(p, q - p)) {
/* If the field name starts with an
* underscore, skip the variable,
* since that indidates a trusted
* field */
iovec[n].iov_base = (char*) p;
iovec[n].iov_len = e - p;
n++;
/* We need to determine the priority
* of this entry for the rate limiting
* logic */
if (e - p == 10 &&
memcmp(p, "PRIORITY=", 10) == 0 &&
p[10] >= '0' &&
p[10] <= '9')
priority = p[10] - '0';
}
remaining -= (e - p) + 1;
p = e + 1;
continue;
} else {
uint64_t l;
char *k;
if (remaining < e - p + 1 + sizeof(uint64_t) + 1) {
log_debug("Failed to parse message, ignoring.");
break;
}
memcpy(&l, e + 1, sizeof(uint64_t));
l = le64toh(l);
if (remaining < e - p + 1 + sizeof(uint64_t) + l + 1 ||
e[1+sizeof(uint64_t)+l] != '\n') {
log_debug("Failed to parse message, ignoring.");
break;
}
k = malloc((e - p) + 1 + l);
if (!k) {
log_error("Out of memory");
break;
}
memcpy(k, p, e - p);
k[e - p] = '=';
memcpy(k + (e - p) + 1, e + 1 + sizeof(uint64_t), l);
if (valid_user_field(p, e - p)) {
iovec[n].iov_base = k;
iovec[n].iov_len = (e - p) + 1 + l;
n++;
} else
free(k);
remaining -= (e - p) + 1 + sizeof(uint64_t) + l + 1;
p = e + 1 + sizeof(uint64_t) + l + 1;
}
}
dispatch_message(s, iovec, n, m, ucred, tv, priority);
for (j = 0; j < n; j++)
if (iovec[j].iov_base < buffer ||
(const uint8_t*) iovec[j].iov_base >= (const uint8_t*) buffer + buffer_size)
free(iovec[j].iov_base);
}
static int stdout_stream_log(StdoutStream *s, const char *p, size_t l) {
struct iovec iovec[15];
char *message = NULL, *syslog_priority = NULL;
unsigned n = 0;
size_t tag_len;
int priority;
assert(s);
assert(p);
priority = s->priority;
if (s->priority_prefix &&
l > 3 &&
p[0] == '<' &&
p[1] >= '0' && p[1] <= '7' &&
p[2] == '>') {
priority = p[1] - '0';
p += 3;
l -= 3;
}
if (l <= 0)
return 0;
if (asprintf(&syslog_priority, "PRIORITY=%i", priority) >= 0)
IOVEC_SET_STRING(iovec[n++], syslog_priority);
tag_len = s->tag ? strlen(s->tag) + 2: 0;
message = malloc(8 + tag_len + l);
if (message) {
memcpy(message, "MESSAGE=", 8);
if (s->tag) {
memcpy(message+8, s->tag, tag_len-2);
memcpy(message+8+tag_len-2, ": ", 2);
}
memcpy(message+8+tag_len, p, l);
iovec[n].iov_base = message;
iovec[n].iov_len = 8+tag_len+l;
n++;
}
dispatch_message(s->server, iovec, n, ELEMENTSOF(iovec), &s->ucred, NULL, priority);
if (s->tee_console) {
int console;
console = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC);
if (console >= 0) {
n = 0;
if (s->tag) {
IOVEC_SET_STRING(iovec[n++], s->tag);
IOVEC_SET_STRING(iovec[n++], ": ");
}
iovec[n].iov_base = (void*) p;
iovec[n].iov_len = l;
n++;
IOVEC_SET_STRING(iovec[n++], (char*) "\n");
writev(console, iovec, n);
}
}
free(message);
free(syslog_priority);
return 0;
}
static int stdout_stream_line(StdoutStream *s, const char *p, size_t l) {
assert(s);
assert(p);
while (l > 0 && strchr(WHITESPACE, *p)) {
l--;
p++;
}
while (l > 0 && strchr(WHITESPACE, *(p+l-1)))
l--;
switch (s->state) {
case STDOUT_STREAM_TAG:
if (l > 0) {
s->tag = strndup(p, l);
if (!s->tag) {
log_error("Out of memory");
return -EINVAL;
}
}
s->state = STDOUT_STREAM_PRIORITY;
return 0;
case STDOUT_STREAM_PRIORITY:
if (l != 1 || *p < '0' || *p > '7') {
log_warning("Failed to parse log priority line.");
return -EINVAL;
}
s->priority = *p - '0';
s->state = STDOUT_STREAM_PRIORITY_PREFIX;
return 0;
case STDOUT_STREAM_PRIORITY_PREFIX:
if (l != 1 || *p < '0' || *p > '1') {
log_warning("Failed to parse priority prefix line.");
return -EINVAL;
}
s->priority_prefix = *p - '0';
s->state = STDOUT_STREAM_TEE_CONSOLE;
return 0;
case STDOUT_STREAM_TEE_CONSOLE:
if (l != 1 || *p < '0' || *p > '1') {
log_warning("Failed to parse tee to console line.");
return -EINVAL;
}
s->tee_console = *p - '0';
s->state = STDOUT_STREAM_RUNNING;
return 0;
case STDOUT_STREAM_RUNNING:
return stdout_stream_log(s, p, l);
}
assert_not_reached("Unknown stream state");
}
static int stdout_stream_scan(StdoutStream *s, bool force_flush) {
char *p;
size_t remaining;
int r;
assert(s);
p = s->buffer;
remaining = s->length;
for (;;) {
char *end;
size_t skip;
end = memchr(p, '\n', remaining);
if (!end) {
if (remaining >= LINE_MAX) {
end = p + LINE_MAX;
skip = LINE_MAX;
} else
break;
} else
skip = end - p + 1;
r = stdout_stream_line(s, p, end - p);
if (r < 0)
return r;
remaining -= skip;
p += skip;
}
if (force_flush && remaining > 0) {
r = stdout_stream_line(s, p, remaining);
if (r < 0)
return r;
p += remaining;
remaining = 0;
}
if (p > s->buffer) {
memmove(s->buffer, p, remaining);
s->length = remaining;
}
return 0;
}
static int stdout_stream_process(StdoutStream *s) {
ssize_t l;
int r;
assert(s);
l = read(s->fd, s->buffer+s->length, sizeof(s->buffer)-1-s->length);
if (l < 0) {
if (errno == EAGAIN)
return 0;
log_warning("Failed to read from stream: %m");
return -errno;
}
if (l == 0) {
r = stdout_stream_scan(s, true);
if (r < 0)
return r;
return 0;
}
s->length += l;
r = stdout_stream_scan(s, false);
if (r < 0)
return r;
return 1;
}
static void stdout_stream_free(StdoutStream *s) {
assert(s);
if (s->server) {
assert(s->server->n_stdout_streams > 0);
s->server->n_stdout_streams --;
LIST_REMOVE(StdoutStream, stdout_stream, s->server->stdout_streams, s);
}
if (s->fd >= 0) {
if (s->server)
epoll_ctl(s->server->epoll_fd, EPOLL_CTL_DEL, s->fd, NULL);
close_nointr_nofail(s->fd);
}
free(s->tag);
free(s);
}
static int stdout_stream_new(Server *s) {
StdoutStream *stream;
int fd, r;
socklen_t len;
struct epoll_event ev;
assert(s);
fd = accept4(s->stdout_fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC);
if (fd < 0) {
if (errno == EAGAIN)
return 0;
log_error("Failed to accept stdout connection: %m");
return -errno;
}
if (s->n_stdout_streams >= STDOUT_STREAMS_MAX) {
log_warning("Too many stdout streams, refusing connection.");
close_nointr_nofail(fd);
return 0;
}
stream = new0(StdoutStream, 1);
if (!stream) {
log_error("Out of memory.");
close_nointr_nofail(fd);
return -ENOMEM;
}
stream->fd = fd;
len = sizeof(stream->ucred);
if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &stream->ucred, &len) < 0) {
log_error("Failed to determine peer credentials: %m");
r = -errno;
goto fail;
}
if (shutdown(fd, SHUT_WR) < 0) {
log_error("Failed to shutdown writing side of socket: %m");
r = -errno;
goto fail;
}
zero(ev);
ev.data.ptr = stream;
ev.events = EPOLLIN;
if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) {
log_error("Failed to add stream to event loop: %m");
r = -errno;
goto fail;
}
stream->server = s;
LIST_PREPEND(StdoutStream, stdout_stream, s->stdout_streams, stream);
s->n_stdout_streams ++;
return 0;
fail:
stdout_stream_free(stream);
return r;
}
static int system_journal_open(Server *s) {
int r;
char *fn;
sd_id128_t machine;
char ids[33];
r = sd_id128_get_machine(&machine);
if (r < 0)
return r;
sd_id128_to_string(machine, ids);
if (!s->system_journal) {
/* First try to create the machine path, but not the prefix */
fn = strappend("/var/log/journal/", ids);
if (!fn)
return -ENOMEM;
(void) mkdir(fn, 0755);
free(fn);
/* The create the system journal file */
fn = join("/var/log/journal/", ids, "/system.journal", NULL);
if (!fn)
return -ENOMEM;
r = journal_file_open(fn, O_RDWR|O_CREAT, 0640, NULL, &s->system_journal);
free(fn);
if (r >= 0) {
journal_default_metrics(&s->system_metrics, s->system_journal->fd);
s->system_journal->metrics = s->system_metrics;
s->system_journal->compress = s->compress;
fix_perms(s->system_journal, 0);
} else if (r < 0) {
if (r == -ENOENT)
r = 0;
else {
log_error("Failed to open system journal: %s", strerror(-r));
return r;
}
}
}
if (!s->runtime_journal) {
fn = join("/run/log/journal/", ids, "/system.journal", NULL);
if (!fn)
return -ENOMEM;
if (s->system_journal) {
/* Try to open the runtime journal, but only
* if it already exists, so that we can flush
* it into the system journal */
r = journal_file_open(fn, O_RDWR, 0640, NULL, &s->runtime_journal);
free(fn);
if (r < 0) {
if (r == -ENOENT)
r = 0;
else {
log_error("Failed to open runtime journal: %s", strerror(-r));
return r;
}
}
} else {
/* OK, we really need the runtime journal, so create
* it if necessary. */
(void) mkdir_parents(fn, 0755);
r = journal_file_open(fn, O_RDWR|O_CREAT, 0640, NULL, &s->runtime_journal);
free(fn);
if (r < 0) {
log_error("Failed to open runtime journal: %s", strerror(-r));
return r;
}
}
if (s->runtime_journal) {
journal_default_metrics(&s->runtime_metrics, s->runtime_journal->fd);
s->runtime_journal->metrics = s->runtime_metrics;
s->runtime_journal->compress = s->compress;
fix_perms(s->runtime_journal, 0);
}
}
return r;
}
static int server_flush_to_var(Server *s) {
char path[] = "/run/log/journal/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
Object *o = NULL;
int r;
sd_id128_t machine;
sd_journal *j;
usec_t ts;
assert(s);
if (!s->runtime_journal)
return 0;
ts = now(CLOCK_MONOTONIC);
if (s->var_available_timestamp + RECHECK_VAR_AVAILABLE_USEC > ts)
return 0;
s->var_available_timestamp = ts;
system_journal_open(s);
if (!s->system_journal)
return 0;
r = sd_id128_get_machine(&machine);
if (r < 0) {
log_error("Failed to get machine id: %s", strerror(-r));
return r;
}
r = sd_journal_open(&j, SD_JOURNAL_RUNTIME_ONLY);
if (r < 0) {
log_error("Failed to read runtime journal: %s", strerror(-r));
return r;
}
SD_JOURNAL_FOREACH(j) {
JournalFile *f;
f = j->current_file;
assert(f && f->current_offset > 0);
r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
if (r < 0) {
log_error("Can't read entry: %s", strerror(-r));
goto finish;
}
r = journal_file_copy_entry(f, s->system_journal, o, f->current_offset, NULL, NULL, NULL);
if (r == -E2BIG) {
log_info("Allocation limit reached.");
journal_file_post_change(s->system_journal);
server_vacuum(s);
r = journal_file_copy_entry(f, s->system_journal, o, f->current_offset, NULL, NULL, NULL);
}
if (r < 0) {
log_error("Can't write entry: %s", strerror(-r));
goto finish;
}
}
finish:
journal_file_post_change(s->system_journal);
journal_file_close(s->runtime_journal);
s->runtime_journal = NULL;
if (r >= 0) {
sd_id128_to_string(machine, path + 17);
rm_rf(path, false, true, false);
}
return r;
}
static void forward_syslog(Server *s, const void *buffer, size_t length, struct ucred *ucred, struct timeval *tv) {
struct msghdr msghdr;
struct iovec iovec;
struct cmsghdr *cmsg;
union {
struct cmsghdr cmsghdr;
uint8_t buf[CMSG_SPACE(sizeof(struct ucred)) +
CMSG_SPACE(sizeof(struct timeval))];
} control;
union sockaddr_union sa;
assert(s);
zero(msghdr);
zero(iovec);
iovec.iov_base = (void*) buffer;
iovec.iov_len = length;
msghdr.msg_iov = &iovec;
msghdr.msg_iovlen = 1;
zero(sa);
sa.un.sun_family = AF_UNIX;
strncpy(sa.un.sun_path, "/run/systemd/syslog", sizeof(sa.un.sun_path));
msghdr.msg_name = &sa;
msghdr.msg_namelen = offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path);
zero(control);
msghdr.msg_control = &control;
msghdr.msg_controllen = sizeof(control);
cmsg = CMSG_FIRSTHDR(&msghdr);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_CREDENTIALS;
cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
memcpy(CMSG_DATA(cmsg), ucred, sizeof(struct ucred));
msghdr.msg_controllen = cmsg->cmsg_len;
/* Forward the syslog message we received via /dev/log to
* /run/systemd/syslog. Unfortunately we currently can't set
* the SO_TIMESTAMP auxiliary data, and hence we don't. */
if (sendmsg(s->syslog_fd, &msghdr, MSG_NOSIGNAL) >= 0)
return;
if (errno == ESRCH) {
struct ucred u;
/* Hmm, presumably the sender process vanished
* by now, so let's fix it as good as we
* can, and retry */
u = *ucred;
u.pid = getpid();
memcpy(CMSG_DATA(cmsg), &u, sizeof(struct ucred));
if (sendmsg(s->syslog_fd, &msghdr, MSG_NOSIGNAL) >= 0)
return;
}
log_debug("Failed to forward syslog message: %m");
}
static int process_event(Server *s, struct epoll_event *ev) {
assert(s);
if (ev->data.fd == s->signal_fd) {
struct signalfd_siginfo sfsi;
ssize_t n;
if (ev->events != EPOLLIN) {
log_info("Got invalid event from epoll.");
return -EIO;
}
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;
}
if (sfsi.ssi_signo == SIGUSR1) {
server_flush_to_var(s);
return 0;
}
log_debug("Received SIG%s", signal_to_string(sfsi.ssi_signo));
return 0;
} else if (ev->data.fd == s->native_fd ||
ev->data.fd == s->syslog_fd) {
if (ev->events != EPOLLIN) {
log_info("Got invalid event from epoll.");
return -EIO;
}
for (;;) {
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;
int v;
if (ioctl(ev->data.fd, SIOCINQ, &v) < 0) {
log_error("SIOCINQ failed: %m");
return -errno;
}
if (v <= 0)
return 1;
if (s->buffer_size < (size_t) v) {
void *b;
size_t l;
l = MAX(LINE_MAX + (size_t) v, s->buffer_size * 2);
b = realloc(s->buffer, l+1);
if (!b) {
log_error("Couldn't increase buffer.");
return -ENOMEM;
}
s->buffer_size = l;
s->buffer = b;
}
zero(iovec);
iovec.iov_base = s->buffer;
iovec.iov_len = s->buffer_size;
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);
}
if (ev->data.fd == s->syslog_fd) {
char *e;
e = memchr(s->buffer, '\n', n);
if (e)
*e = 0;
else
s->buffer[n] = 0;
forward_syslog(s, s->buffer, n, ucred, tv);
process_syslog_message(s, strstrip(s->buffer), ucred, tv);
} else
process_native_message(s, s->buffer, n, ucred, tv);
}
return 1;
} else if (ev->data.fd == s->stdout_fd) {
if (ev->events != EPOLLIN) {
log_info("Got invalid event from epoll.");
return -EIO;
}
stdout_stream_new(s);
return 1;
} else {
StdoutStream *stream;
if ((ev->events|EPOLLIN|EPOLLHUP) != (EPOLLIN|EPOLLHUP)) {
log_info("Got invalid event from epoll.");
return -EIO;
}
/* If it is none of the well-known fds, it must be an
* stdout stream fd. Note that this is a bit ugly here
* (since we rely that none of the well-known fds
* could be interpreted as pointer), but nonetheless
* safe, since the well-known fds would never get an
* fd > 4096, i.e. beyond the first memory page */
stream = ev->data.ptr;
if (stdout_stream_process(stream) <= 0)
stdout_stream_free(stream);
return 1;
}
log_error("Unknown event.");
return 0;
}
static int open_syslog_socket(Server *s) {
union sockaddr_union sa;
int one, r;
struct epoll_event ev;
struct timeval tv;
assert(s);
if (s->syslog_fd < 0) {
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, "/dev/log", sizeof(sa.un.sun_path));
unlink(sa.un.sun_path);
r = bind(s->syslog_fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path));
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;
}
/* Since we use the same socket for forwarding this to some
* other syslog implementation, make sure we don't hang
* forever */
timeval_store(&tv, SYSLOG_TIMEOUT_USEC);
if (setsockopt(s->syslog_fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)) < 0) {
log_error("SO_SNDTIMEO 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 syslog server fd to epoll object: %m");
return -errno;
}
return 0;
}
static int open_native_socket(Server*s) {
union sockaddr_union sa;
int one, r;
struct epoll_event ev;
assert(s);
if (s->native_fd < 0) {
s->native_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
if (s->native_fd < 0) {
log_error("socket() failed: %m");
return -errno;
}
zero(sa);
sa.un.sun_family = AF_UNIX;
strncpy(sa.un.sun_path, "/run/systemd/journal", sizeof(sa.un.sun_path));
unlink(sa.un.sun_path);
r = bind(s->native_fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path));
if (r < 0) {
log_error("bind() failed: %m");
return -errno;
}
chmod(sa.un.sun_path, 0666);
}
one = 1;
r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one));
if (r < 0) {
log_error("SO_PASSCRED failed: %m");
return -errno;
}
one = 1;
r = setsockopt(s->native_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->native_fd;
if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->native_fd, &ev) < 0) {
log_error("Failed to add native server fd to epoll object: %m");
return -errno;
}
return 0;
}
static int open_stdout_socket(Server *s) {
union sockaddr_union sa;
int r;
struct epoll_event ev;
assert(s);
if (s->stdout_fd < 0) {
s->stdout_fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0);
if (s->stdout_fd < 0) {
log_error("socket() failed: %m");
return -errno;
}
zero(sa);
sa.un.sun_family = AF_UNIX;
strncpy(sa.un.sun_path, "/run/systemd/stdout", sizeof(sa.un.sun_path));
unlink(sa.un.sun_path);
r = bind(s->stdout_fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path));
if (r < 0) {
log_error("bind() failed: %m");
return -errno;
}
chmod(sa.un.sun_path, 0666);
if (listen(s->stdout_fd, SOMAXCONN) < 0) {
log_error("liste() failed: %m");
return -errno;
}
}
zero(ev);
ev.events = EPOLLIN;
ev.data.fd = s->stdout_fd;
if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->stdout_fd, &ev) < 0) {
log_error("Failed to add stdout server fd to epoll object: %m");
return -errno;
}
return 0;
}
static int open_signalfd(Server *s) {
sigset_t mask;
struct epoll_event ev;
assert(s);
assert_se(sigemptyset(&mask) == 0);
sigset_add_many(&mask, SIGINT, SIGTERM, SIGUSR1, -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 int server_init(Server *s) {
int n, r, fd;
assert(s);
zero(*s);
s->syslog_fd = s->native_fd = s->stdout_fd = s->signal_fd = s->epoll_fd = -1;
s->compress = true;
memset(&s->system_metrics, 0xFF, sizeof(s->system_metrics));
memset(&s->runtime_metrics, 0xFF, sizeof(s->runtime_metrics));
s->user_journals = hashmap_new(trivial_hash_func, trivial_compare_func);
if (!s->user_journals) {
log_error("Out of memory.");
return -ENOMEM;
}
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;
}
for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd++) {
if (sd_is_socket_unix(fd, SOCK_DGRAM, -1, "/run/systemd/native", 0) > 0) {
if (s->native_fd >= 0) {
log_error("Too many native sockets passed.");
return -EINVAL;
}
s->native_fd = fd;
} else if (sd_is_socket_unix(fd, SOCK_STREAM, 1, "/run/systemd/stdout", 0) > 0) {
if (s->stdout_fd >= 0) {
log_error("Too many stdout sockets passed.");
return -EINVAL;
}
s->stdout_fd = fd;
} else if (sd_is_socket_unix(fd, SOCK_DGRAM, -1, "/dev/log", 0) > 0) {
if (s->syslog_fd >= 0) {
log_error("Too many /dev/log sockets passed.");
return -EINVAL;
}
s->syslog_fd = fd;
} else {
log_error("Unknown socket passed.");
return -EINVAL;
}
}
r = open_syslog_socket(s);
if (r < 0)
return r;
r = open_native_socket(s);
if (r < 0)
return r;
r = open_stdout_socket(s);
if (r < 0)
return r;
r = system_journal_open(s);
if (r < 0)
return r;
r = open_signalfd(s);
if (r < 0)
return r;
s->rate_limit = journal_rate_limit_new(DEFAULT_RATE_LIMIT_INTERVAL, DEFAULT_RATE_LIMIT_BURST);
if (!s->rate_limit)
return -ENOMEM;
return 0;
}
static void server_done(Server *s) {
JournalFile *f;
assert(s);
while (s->stdout_streams)
stdout_stream_free(s->stdout_streams);
if (s->system_journal)
journal_file_close(s->system_journal);
if (s->runtime_journal)
journal_file_close(s->runtime_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);
if (s->native_fd >= 0)
close_nointr_nofail(s->native_fd);
if (s->stdout_fd >= 0)
close_nointr_nofail(s->stdout_fd);
if (s->rate_limit)
journal_rate_limit_free(s->rate_limit);
free(s->buffer);
}
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_CONSOLE);
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 requests...");
server_vacuum(&server);
server_flush_to_var(&server);
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;
}
log_debug("systemd-journald stopped as pid %lu", (unsigned long) getpid());
finish:
sd_notify(false,
"STATUS=Shutting down...");
server_done(&server);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}