From e0a3cd2cb02c465c13dcc4e2c092c9e14883ad59 Mon Sep 17 00:00:00 2001
From: Lukas Nykryn <lnykryn@redhat.com>
Date: Wed, 3 Feb 2016 10:37:48 +0100
Subject: [PATCH] Revert "Revert "journald: allow restarting journald without
losing stream connections""
This reverts commit 91cb89c1b79ef3c475d91319edb0c052cb9f2724.
Resolves: #1359939
---
src/journal/journald-server.c | 26 ++-
src/journal/journald-stream.c | 371 ++++++++++++++++++++++++++++++++++++------
src/journal/journald-stream.h | 3 +-
3 files changed, 340 insertions(+), 60 deletions(-)
diff --git a/src/journal/journald-server.c b/src/journal/journald-server.c
index 07426b41e..c1358e1e9 100644
--- a/src/journal/journald-server.c
+++ b/src/journal/journald-server.c
@@ -1477,6 +1477,7 @@ static int server_open_hostname(Server *s) {
}
int server_init(Server *s) {
+ _cleanup_fdset_free_ FDSet *fds = NULL;
int n, r, fd;
assert(s);
@@ -1573,26 +1574,33 @@ int server_init(Server *s) {
s->audit_fd = fd;
} else {
- log_warning("Unknown socket passed as file descriptor %d, ignoring.", fd);
- /* Let's close the fd, better be safe than
- sorry. The fd might reference some resource
- that we really want to release if we don't
- make use of it. */
+ if (!fds) {
+ fds = fdset_new();
+ if (!fds)
+ return log_oom();
+ }
- safe_close(fd);
+ r = fdset_put(fds, fd);
+ if (r < 0)
+ return log_oom();
}
}
- r = server_open_syslog_socket(s);
+ r = server_open_stdout_socket(s, fds);
if (r < 0)
return r;
- r = server_open_native_socket(s);
+ if (fdset_size(fds) > 0) {
+ log_warning("%u unknown file descriptors passed, closing.", fdset_size(fds));
+ fds = fdset_free(fds);
+ }
+
+ r = server_open_syslog_socket(s);
if (r < 0)
return r;
- r = server_open_stdout_socket(s);
+ r = server_open_native_socket(s);
if (r < 0)
return r;
diff --git a/src/journal/journald-stream.c b/src/journal/journald-stream.c
index b8607144b..15c9110c0 100644
--- a/src/journal/journald-stream.c
+++ b/src/journal/journald-stream.c
@@ -28,8 +28,11 @@
#endif
#include "sd-event.h"
+#include "sd-daemon.h"
#include "socket-util.h"
#include "selinux-util.h"
+#include "mkdir.h"
+#include "fileio.h"
#include "journald-server.h"
#include "journald-stream.h"
#include "journald-syslog.h"
@@ -66,14 +69,148 @@ struct StdoutStream {
bool forward_to_kmsg:1;
bool forward_to_console:1;
+ bool fdstore:1;
+
char buffer[LINE_MAX+1];
size_t length;
sd_event_source *event_source;
+ char *state_file;
+
LIST_FIELDS(StdoutStream, stdout_stream);
};
+void stdout_stream_free(StdoutStream *s) {
+ if (!s)
+ return;
+
+ if (s->server) {
+ assert(s->server->n_stdout_streams > 0);
+ s->server->n_stdout_streams --;
+ LIST_REMOVE(stdout_stream, s->server->stdout_streams, s);
+ }
+
+ if (s->event_source) {
+ sd_event_source_set_enabled(s->event_source, SD_EVENT_OFF);
+ s->event_source = sd_event_source_unref(s->event_source);
+ }
+
+ safe_close(s->fd);
+ free(s->label);
+ free(s->identifier);
+ free(s->unit_id);
+ free(s->state_file);
+
+ free(s);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(StdoutStream*, stdout_stream_free);
+
+static void stdout_stream_destroy(StdoutStream *s) {
+ if (!s)
+ return;
+
+ if (s->state_file)
+ unlink(s->state_file);
+
+ stdout_stream_free(s);
+}
+
+static int stdout_stream_save(StdoutStream *s) {
+ _cleanup_free_ char *temp_path = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ int r;
+
+ assert(s);
+
+ if (s->state != STDOUT_STREAM_RUNNING)
+ return 0;
+
+ if (!s->state_file) {
+ struct stat st;
+
+ r = fstat(s->fd, &st);
+ if (r < 0)
+ return log_warning_errno(errno, "Failed to stat connected stream: %m");
+
+ /* We use device and inode numbers as identifier for the stream */
+ if (asprintf(&s->state_file, "/run/systemd/journal/streams/%lu:%lu", (unsigned long) st.st_dev, (unsigned long) st.st_ino) < 0)
+ return log_oom();
+ }
+
+ mkdir_p("/run/systemd/journal/streams", 0755);
+
+ r = fopen_temporary(s->state_file, &f, &temp_path);
+ if (r < 0)
+ goto finish;
+
+ fprintf(f,
+ "# This is private data. Do not parse\n"
+ "PRIORITY=%i\n"
+ "LEVEL_PREFIX=%i\n"
+ "FORWARD_TO_SYSLOG=%i\n"
+ "FORWARD_TO_KMSG=%i\n"
+ "FORWARD_TO_CONSOLE=%i\n",
+ s->priority,
+ s->level_prefix,
+ s->forward_to_syslog,
+ s->forward_to_kmsg,
+ s->forward_to_console);
+
+ if (!isempty(s->identifier)) {
+ _cleanup_free_ char *escaped;
+
+ escaped = cescape(s->identifier);
+ if (!escaped) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ fprintf(f, "IDENTIFIER=%s\n", escaped);
+ }
+
+ if (!isempty(s->unit_id)) {
+ _cleanup_free_ char *escaped;
+
+ escaped = cescape(s->unit_id);
+ if (!escaped) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ fprintf(f, "UNIT=%s\n", escaped);
+ }
+
+ r = fflush_and_check(f);
+ if (r < 0)
+ goto finish;
+
+ if (rename(temp_path, s->state_file) < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ free(temp_path);
+ temp_path = NULL;
+
+ /* Store the connection fd in PID 1, so that we get it passed
+ * in again on next start */
+ if (!s->fdstore) {
+ sd_pid_notify_with_fds(0, false, "FDSTORE=1", &s->fd, 1);
+ s->fdstore = true;
+ }
+
+finish:
+ if (temp_path)
+ unlink(temp_path);
+
+ if (r < 0)
+ log_error_errno(r, "Failed to save stream data %s: %m", s->state_file);
+
+ return r;
+}
+
static int stdout_stream_log(StdoutStream *s, const char *p) {
struct iovec iovec[N_IOVEC_META_FIELDS + 5];
int priority;
@@ -219,6 +356,9 @@ static int stdout_stream_line(StdoutStream *s, char *p) {
s->forward_to_console = !!r;
s->state = STDOUT_STREAM_RUNNING;
+
+ /* Try to save the stream, so that journald can be restarted and we can recover */
+ (void) stdout_stream_save(s);
return 0;
case STDOUT_STREAM_RUNNING:
@@ -313,36 +453,62 @@ static int stdout_stream_process(sd_event_source *es, int fd, uint32_t revents,
return 1;
terminate:
- stdout_stream_free(s);
+ stdout_stream_destroy(s);
return 0;
}
-void stdout_stream_free(StdoutStream *s) {
+static int stdout_stream_install(Server *s, int fd, StdoutStream **ret) {
+ _cleanup_(stdout_stream_freep) StdoutStream *stream = NULL;
+ int r;
+
assert(s);
+ assert(fd >= 0);
- if (s->server) {
- assert(s->server->n_stdout_streams > 0);
- s->server->n_stdout_streams --;
- LIST_REMOVE(stdout_stream, s->server->stdout_streams, s);
- }
+ stream = new0(StdoutStream, 1);
+ if (!stream)
+ return log_oom();
- if (s->event_source) {
- sd_event_source_set_enabled(s->event_source, SD_EVENT_OFF);
- s->event_source = sd_event_source_unref(s->event_source);
+ stream->fd = -1;
+ stream->priority = LOG_INFO;
+
+ r = getpeercred(fd, &stream->ucred);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine peer credentials: %m");
+
+ if (mac_selinux_use()) {
+ r = getpeersec(fd, &stream->label);
+ if (r < 0 && r != -EOPNOTSUPP)
+ (void) log_warning_errno(r, "Failed to determine peer security context: %m");
}
- safe_close(s->fd);
+ (void) shutdown(fd, SHUT_WR);
- free(s->label);
- free(s->identifier);
- free(s->unit_id);
- free(s);
+ r = sd_event_add_io(s->event, &stream->event_source, fd, EPOLLIN, stdout_stream_process, stream);
+ if (r < 0)
+ return log_error_errno(r, "Failed to add stream to event loop: %m");
+
+ r = sd_event_source_set_priority(stream->event_source, SD_EVENT_PRIORITY_NORMAL+5);
+ if (r < 0)
+ return log_error_errno(r, "Failed to adjust stdout event source priority: %m");
+
+ stream->fd = fd;
+
+ stream->server = s;
+ LIST_PREPEND(stdout_stream, s->stdout_streams, stream);
+ s->n_stdout_streams ++;
+
+ if (ret)
+ *ret = stream;
+
+ stream = NULL;
+
+ return 0;
}
static int stdout_stream_new(sd_event_source *es, int listen_fd, uint32_t revents, void *userdata) {
+ _cleanup_close_ int fd = -1;
Server *s = userdata;
- StdoutStream *stream;
- int fd, r;
+ int r;
assert(s);
@@ -362,61 +528,163 @@ static int stdout_stream_new(sd_event_source *es, int listen_fd, uint32_t revent
if (s->n_stdout_streams >= STDOUT_STREAMS_MAX) {
log_warning("Too many stdout streams, refusing connection.");
- safe_close(fd);
return 0;
}
- stream = new0(StdoutStream, 1);
- if (!stream) {
- safe_close(fd);
- return log_oom();
+ r = stdout_stream_install(s, fd, NULL);
+ if (r < 0)
+ return r;
+
+ fd = -1;
+ return 0;
+}
+
+static int stdout_stream_load(StdoutStream *stream, const char *fname) {
+ _cleanup_free_ char
+ *priority = NULL,
+ *level_prefix = NULL,
+ *forward_to_syslog = NULL,
+ *forward_to_kmsg = NULL,
+ *forward_to_console = NULL;
+ int r;
+
+ assert(stream);
+ assert(fname);
+
+ if (!stream->state_file) {
+ stream->state_file = strappend("/run/systemd/journal/streams/", fname);
+ if (!stream->state_file)
+ return log_oom();
}
- stream->fd = fd;
+ r = parse_env_file(stream->state_file, NEWLINE,
+ "PRIORITY", &priority,
+ "LEVEL_PREFIX", &level_prefix,
+ "FORWARD_TO_SYSLOG", &forward_to_syslog,
+ "FORWARD_TO_KMSG", &forward_to_kmsg,
+ "FORWARD_TO_CONSOLE", &forward_to_console,
+ "IDENTIFIER", &stream->identifier,
+ "UNIT", &stream->unit_id,
+ NULL);
+ if (r < 0)
+ return log_error_errno(r, "Failed to read: %s", stream->state_file);
- r = getpeercred(fd, &stream->ucred);
- if (r < 0) {
- log_error_errno(errno, "Failed to determine peer credentials: %m");
- goto fail;
+ if (priority) {
+ int p;
+
+ p = log_level_from_string(priority);
+ if (p >= 0)
+ stream->priority = p;
}
-#ifdef HAVE_SELINUX
- if (mac_selinux_use()) {
- r = getpeersec(fd, &stream->label);
- if (r < 0 && r != -EOPNOTSUPP)
- (void) log_warning_errno(r, "Failed to determine peer security context: %m");
+ if (level_prefix) {
+ r = parse_boolean(level_prefix);
+ if (r >= 0)
+ stream->level_prefix = r;
}
-#endif
- if (shutdown(fd, SHUT_WR) < 0) {
- log_error_errno(errno, "Failed to shutdown writing side of socket: %m");
- goto fail;
+ if (forward_to_syslog) {
+ r = parse_boolean(forward_to_syslog);
+ if (r >= 0)
+ stream->forward_to_syslog = r;
}
- r = sd_event_add_io(s->event, &stream->event_source, fd, EPOLLIN, stdout_stream_process, stream);
- if (r < 0) {
- log_error_errno(r, "Failed to add stream to event loop: %m");
- goto fail;
+ if (forward_to_kmsg) {
+ r = parse_boolean(forward_to_kmsg);
+ if (r >= 0)
+ stream->forward_to_kmsg = r;
}
- r = sd_event_source_set_priority(stream->event_source, SD_EVENT_PRIORITY_NORMAL+5);
- if (r < 0) {
- log_error_errno(r, "Failed to adjust stdout event source priority: %m");
- goto fail;
+ if (forward_to_console) {
+ r = parse_boolean(forward_to_console);
+ if (r >= 0)
+ stream->forward_to_console = r;
}
- stream->server = s;
- LIST_PREPEND(stdout_stream, s->stdout_streams, stream);
- s->n_stdout_streams ++;
+ return 0;
+}
+
+static int stdout_stream_restore(Server *s, const char *fname, int fd) {
+ StdoutStream *stream;
+ int r;
+
+ assert(s);
+ assert(fname);
+ assert(fd >= 0);
+
+ if (s->n_stdout_streams >= STDOUT_STREAMS_MAX) {
+ log_warning("Too many stdout streams, refusing restoring of stream.");
+ return -ENOBUFS;
+ }
+
+ r = stdout_stream_install(s, fd, &stream);
+ if (r < 0)
+ return r;
+
+ stream->state = STDOUT_STREAM_RUNNING;
+ stream->fdstore = true;
+
+ /* Ignore all parsing errors */
+ (void) stdout_stream_load(stream, fname);
return 0;
+}
+
+static int server_restore_streams(Server *s, FDSet *fds) {
+ _cleanup_closedir_ DIR *d = NULL;
+ struct dirent *de;
+ int r;
+
+ d = opendir("/run/systemd/journal/streams");
+ if (!d) {
+ if (errno == ENOENT)
+ return 0;
+
+ return log_warning_errno(errno, "Failed to enumerate /run/systemd/journal/streams: %m");
+ }
+
+ FOREACH_DIRENT(de, d, goto fail) {
+ unsigned long st_dev, st_ino;
+ bool found = false;
+ Iterator i;
+ int fd;
+
+ if (sscanf(de->d_name, "%lu:%lu", &st_dev, &st_ino) != 2)
+ continue;
+
+ FDSET_FOREACH(fd, fds, i) {
+ struct stat st;
+
+ if (fstat(fd, &st) < 0)
+ return log_error_errno(errno, "Failed to stat %s: %m", de->d_name);
+
+ if (S_ISSOCK(st.st_mode) && st.st_dev == st_dev && st.st_ino == st_ino) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ /* No file descriptor? Then let's delete the state file */
+ log_debug("Cannot restore stream file %s", de->d_name);
+ unlinkat(dirfd(d), de->d_name, 0);
+ continue;
+ }
+
+ fdset_remove(fds, fd);
+
+ r = stdout_stream_restore(s, de->d_name, fd);
+ if (r < 0)
+ safe_close(fd);
+ }
-fail:
- stdout_stream_free(stream);
return 0;
+
+fail:
+ return log_error_errno(errno, "Failed to read streams directory: %m");
}
-int server_open_stdout_socket(Server *s) {
+int server_open_stdout_socket(Server *s, FDSet *fds) {
int r;
assert(s);
@@ -452,5 +720,8 @@ int server_open_stdout_socket(Server *s) {
if (r < 0)
return log_error_errno(r, "Failed to adjust priority of stdout server event source: %m");
+ /* Try to restore streams, but don't bother if this fails */
+ (void) server_restore_streams(s, fds);
+
return 0;
}
diff --git a/src/journal/journald-stream.h b/src/journal/journald-stream.h
index 8cad01296..94bf955d7 100644
--- a/src/journal/journald-stream.h
+++ b/src/journal/journald-stream.h
@@ -21,8 +21,9 @@
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
+#include "fdset.h"
#include "journald-server.h"
-int server_open_stdout_socket(Server *s);
+int server_open_stdout_socket(Server *s, FDSet *fds);
void stdout_stream_free(StdoutStream *s);