X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fjournal%2Fjournald.c;h=7c89689e843eacfd08ba4eafd1214160489118ea;hp=36f9abe47ecd957e347a45f7be11e0a09840e2fa;hb=cee5e9a7ca75f05d4a0f7759566e657587a500d5;hpb=3146a302d184d64a5c75237129f9e4f54ce46cd3

diff --git a/src/journal/journald.c b/src/journal/journald.c
index 36f9abe47..7c89689e8 100644
--- a/src/journal/journald.c
+++ b/src/journal/journald.c
@@ -29,6 +29,7 @@
 #include <sys/ioctl.h>
 #include <linux/sockios.h>
 #include <sys/statvfs.h>
+#include <sys/mman.h>
 
 #include <systemd/sd-journal.h>
 #include <systemd/sd-messages.h>
@@ -70,6 +71,7 @@
 #define RECHECK_AVAILABLE_SPACE_USEC (30*USEC_PER_SEC)
 
 #define N_IOVEC_META_FIELDS 17
+#define N_IOVEC_KERNEL_FIELDS 64
 
 #define ENTRY_SIZE_MAX (1024*1024*32)
 
@@ -393,7 +395,7 @@ static void server_vacuum(Server *s) {
 
         if (s->system_journal) {
                 if (asprintf(&p, "/var/log/journal/%s", ids) < 0) {
-                        log_error("Out of memory.");
+                        log_oom();
                         return;
                 }
 
@@ -405,7 +407,7 @@ static void server_vacuum(Server *s) {
 
         if (s->runtime_journal) {
                 if (asprintf(&p, "/run/log/journal/%s", ids) < 0) {
-                        log_error("Out of memory.");
+                        log_oom();
                         return;
                 }
 
@@ -721,7 +723,7 @@ static void driver_message(Server *s, sd_id128_t message_id, const char *format,
         assert(s);
         assert(format);
 
-        IOVEC_SET_STRING(iovec[n++], "PRIORITY=5");
+        IOVEC_SET_STRING(iovec[n++], "PRIORITY=6");
         IOVEC_SET_STRING(iovec[n++], "_TRANSPORT=driver");
 
         memcpy(buffer, "MESSAGE=", 8);
@@ -955,14 +957,16 @@ static void forward_kmsg(Server *s, int priority, const char *identifier, const
         char header_priority[6], header_pid[16];
         int n = 0;
         char *ident_buf = NULL;
-        int fd;
 
         assert(s);
         assert(priority >= 0);
         assert(priority <= 999);
         assert(message);
 
-        if (LOG_PRI(priority) > s->max_level_kmsg)
+        if (_unlikely_(LOG_PRI(priority) > s->max_level_kmsg))
+                return;
+
+        if (_unlikely_(s->dev_kmsg_fd < 0))
                 return;
 
         /* Never allow messages with kernel facility to be written to
@@ -997,18 +1001,9 @@ static void forward_kmsg(Server *s, int priority, const char *identifier, const
         IOVEC_SET_STRING(iovec[n++], message);
         IOVEC_SET_STRING(iovec[n++], "\n");
 
-        fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC);
-        if (fd < 0) {
-                log_debug("Failed to open /dev/kmsg for logging: %s", strerror(errno));
-                goto finish;
-        }
-
-        if (writev(fd, iovec, n) < 0)
+        if (writev(s->dev_kmsg_fd, iovec, n) < 0)
                 log_debug("Failed to write to /dev/kmsg for logging: %s", strerror(errno));
 
-        close_nointr_nofail(fd);
-
-finish:
         free(ident_buf);
 }
 
@@ -1174,6 +1169,7 @@ static void process_syslog_message(Server *s, const char *buf, struct ucred *ucr
         free(syslog_priority);
         free(syslog_facility);
         free(syslog_identifier);
+        free(syslog_pid);
 }
 
 static bool valid_user_field(const char *p, size_t l) {
@@ -1270,7 +1266,7 @@ static void process_native_message(
                         u = MAX((n+N_IOVEC_META_FIELDS+1) * 2U, 4U);
                         c = realloc(iovec, u * sizeof(struct iovec));
                         if (!c) {
-                                log_error("Out of memory");
+                                log_oom();
                                 break;
                         }
 
@@ -1357,7 +1353,7 @@ static void process_native_message(
 
                         k = malloc((e - p) + 1 + l);
                         if (!k) {
-                                log_error("Out of memory");
+                                log_oom();
                                 break;
                         }
 
@@ -1450,7 +1446,7 @@ static void process_native_file(
 
         p = malloc(st.st_size);
         if (!p) {
-                log_error("Out of memory");
+                log_oom();
                 return;
         }
 
@@ -1542,10 +1538,8 @@ static int stdout_stream_line(StdoutStream *s, char *p) {
                         s->identifier = NULL;
                 else  {
                         s->identifier = strdup(p);
-                        if (!s->identifier) {
-                                log_error("Out of memory");
-                                return -ENOMEM;
-                        }
+                        if (!s->identifier)
+                                return log_oom();
                 }
 
                 s->state = STDOUT_STREAM_UNIT_ID;
@@ -1557,10 +1551,8 @@ static int stdout_stream_line(StdoutStream *s, char *p) {
                                 s->unit_id = NULL;
                         else  {
                                 s->unit_id = strdup(p);
-                                if (!s->unit_id) {
-                                        log_error("Out of memory");
-                                        return -ENOMEM;
-                                }
+                                if (!s->unit_id)
+                                        return log_oom();
                         }
                 }
 
@@ -1761,9 +1753,8 @@ static int stdout_stream_new(Server *s) {
 
         stream = new0(StdoutStream, 1);
         if (!stream) {
-                log_error("Out of memory.");
                 close_nointr_nofail(fd);
-                return -ENOMEM;
+                return log_oom();
         }
 
         stream->fd = fd;
@@ -1806,110 +1797,143 @@ fail:
         return r;
 }
 
-static int parse_kernel_timestamp(char **_p, usec_t *t) {
-        usec_t r;
-        int k, i;
-        char *p;
+static bool is_us(const char *pid) {
+        pid_t t;
 
-        assert(_p);
-        assert(*_p);
-        assert(t);
+        assert(pid);
 
-        p = *_p;
+        if (parse_pid(pid, &t) < 0)
+                return false;
 
-        if (strlen(p) < 14 || p[0] != '[' || p[13] != ']' || p[6] != '.')
-                return 0;
+        return t == getpid();
+}
 
-        r = 0;
+static void dev_kmsg_record(Server *s, char *p, size_t l) {
+        struct iovec iovec[N_IOVEC_META_FIELDS + 7 + N_IOVEC_KERNEL_FIELDS];
+        char *message = NULL, *syslog_priority = NULL, *syslog_pid = NULL, *syslog_facility = NULL, *syslog_identifier = NULL, *source_time = NULL;
+        int priority, r;
+        unsigned n = 0, z = 0, j;
+        usec_t usec;
+        char *identifier = NULL, *pid = NULL, *e, *f, *k;
+        uint64_t serial;
+        size_t pl;
 
-        for (i = 1; i <= 5; i++) {
-                r *= 10;
+        assert(s);
+        assert(p);
 
-                if (p[i] == ' ')
-                        continue;
+        if (l <= 0)
+                return;
 
-                k = undecchar(p[i]);
-                if (k < 0)
-                        return 0;
+        e = memchr(p, ',', l);
+        if (!e)
+                return;
+        *e = 0;
 
-                r += k;
-        }
+        r = safe_atoi(p, &priority);
+        if (r < 0 || priority < 0 || priority > 999)
+                return;
+
+        if (s->forward_to_kmsg && (priority & LOG_FACMASK) != LOG_KERN)
+                return;
 
-        for (i = 7; i <= 12; i++) {
-                r *= 10;
+        l -= (e - p) + 1;
+        p = e + 1;
+        e = memchr(p, ',', l);
+        if (!e)
+                return;
+        *e = 0;
 
-                k = undecchar(p[i]);
-                if (k < 0)
-                        return 0;
+        r = safe_atou64(p, &serial);
+        if (r < 0)
+                return;
+
+        if (s->kernel_seqnum) {
+                /* We already read this one? */
+                if (serial < *s->kernel_seqnum)
+                        return;
 
-                r += k;
+                /* Did we lose any? */
+                if (serial > *s->kernel_seqnum)
+                        driver_message(s, SD_MESSAGE_JOURNAL_MISSED, "Missed %llu kernel messages", (unsigned long long) serial - *s->kernel_seqnum - 1);
+
+                /* Make sure we never read this one again. Note that
+                 * we always store the next message serial we expect
+                 * here, simply because this makes handling the first
+                 * message with serial 0 easy. */
+                *s->kernel_seqnum = serial + 1;
         }
 
-        *t = r;
-        *_p += 14;
-        *_p += strspn(*_p, WHITESPACE);
+        l -= (e - p) + 1;
+        p = e + 1;
+        f = memchr(p, ';', l);
+        if (!f)
+                return;
+        /* Kernel 3.6 has the flags field, kernel 3.5 lacks that */
+        e = memchr(p, ',', l);
+        if (!e || f < e)
+                e = f;
+        *e = 0;
 
-        return 1;
-}
+        r = parse_usec(p, &usec);
+        if (r < 0)
+                return;
 
-static bool is_us(const char *pid) {
-        pid_t t;
+        l -= (f - p) + 1;
+        p = f + 1;
+        e = memchr(p, '\n', l);
+        if (!e)
+                return;
+        *e = 0;
 
-        assert(pid);
+        pl = e - p;
+        l -= (e - p) + 1;
+        k = e + 1;
 
-        if (parse_pid(pid, &t) < 0)
-                return false;
+        for (j = 0; l > 0 && j < N_IOVEC_KERNEL_FIELDS; j++) {
+                char *m;
+                /* Meta data fields attached */
 
-        return t == getpid();
-}
+                if (*k != ' ')
+                        break;
 
-static void proc_kmsg_line(Server *s, const char *p) {
-        struct iovec iovec[N_IOVEC_META_FIELDS + 7];
-        char *message = NULL, *syslog_priority = NULL, *syslog_pid = NULL, *syslog_facility = NULL, *syslog_identifier = NULL, *source_time = NULL;
-        int priority = LOG_KERN | LOG_INFO;
-        unsigned n = 0;
-        usec_t usec;
-        char *identifier = NULL, *pid = NULL;
+                k ++, l --;
 
-        assert(s);
-        assert(p);
+                e = memchr(k, '\n', l);
+                if (!e)
+                        return;
 
-        if (isempty(p))
-                return;
+                *e = 0;
 
-        parse_syslog_priority((char **) &p, &priority);
+                m = cunescape_length_with_prefix(k, e - k, "_KERNEL_");
+                if (!m)
+                        break;
 
-        if (s->forward_to_kmsg && (priority & LOG_FACMASK) != LOG_KERN)
-                return;
+                IOVEC_SET_STRING(iovec[n++], m);
+                z++;
 
-        if (parse_kernel_timestamp((char **) &p, &usec) > 0) {
-                if (asprintf(&source_time, "_SOURCE_MONOTONIC_TIMESTAMP=%llu",
-                             (unsigned long long) usec) >= 0)
-                        IOVEC_SET_STRING(iovec[n++], source_time);
+                l -= (e - k) + 1;
+                k = e + 1;
         }
 
+        if (asprintf(&source_time, "_SOURCE_MONOTONIC_TIMESTAMP=%llu",
+                     (unsigned long long) usec) >= 0)
+                IOVEC_SET_STRING(iovec[n++], source_time);
+
         IOVEC_SET_STRING(iovec[n++], "_TRANSPORT=kernel");
 
         if (asprintf(&syslog_priority, "PRIORITY=%i", priority & LOG_PRIMASK) >= 0)
                 IOVEC_SET_STRING(iovec[n++], syslog_priority);
 
-        if ((priority & LOG_FACMASK) == LOG_KERN) {
-
-                if (s->forward_to_syslog)
-                        forward_syslog(s, priority, "kernel", p, NULL, NULL);
-
+        if ((priority & LOG_FACMASK) == LOG_KERN)
                 IOVEC_SET_STRING(iovec[n++], "SYSLOG_IDENTIFIER=kernel");
-        } else {
-                read_identifier(&p, &identifier, &pid);
+        else {
+                read_identifier((const char**) &p, &identifier, &pid);
 
                 /* Avoid any messages we generated ourselves via
                  * log_info() and friends. */
                 if (pid && is_us(pid))
                         goto finish;
 
-                if (s->forward_to_syslog)
-                        forward_syslog(s, priority, identifier, p, NULL, NULL);
-
                 if (identifier) {
                         syslog_identifier = strappend("SYSLOG_IDENTIFIER=", identifier);
                         if (syslog_identifier)
@@ -1926,13 +1950,16 @@ static void proc_kmsg_line(Server *s, const char *p) {
                         IOVEC_SET_STRING(iovec[n++], syslog_facility);
         }
 
-        message = strappend("MESSAGE=", p);
+        message = cunescape_length_with_prefix(p, pl, "MESSAGE=");
         if (message)
                 IOVEC_SET_STRING(iovec[n++], message);
 
         dispatch_message(s, iovec, n, ELEMENTSOF(iovec), NULL, NULL, NULL, 0, NULL, priority);
 
 finish:
+        for (j = 0; j < z; j++)
+                free(iovec[j].iov_base);
+
         free(message);
         free(syslog_priority);
         free(syslog_identifier);
@@ -1943,41 +1970,6 @@ finish:
         free(pid);
 }
 
-static void proc_kmsg_scan(Server *s) {
-        char *p;
-        size_t remaining;
-
-        assert(s);
-
-        p = s->proc_kmsg_buffer;
-        remaining = s->proc_kmsg_length;
-        for (;;) {
-                char *end;
-                size_t skip;
-
-                end = memchr(p, '\n', remaining);
-                if (end)
-                        skip = end - p + 1;
-                else if (remaining >= sizeof(s->proc_kmsg_buffer) - 1) {
-                        end = p + sizeof(s->proc_kmsg_buffer) - 1;
-                        skip = remaining;
-                } else
-                        break;
-
-                *end = 0;
-
-                proc_kmsg_line(s, p);
-
-                remaining -= skip;
-                p += skip;
-        }
-
-        if (p > s->proc_kmsg_buffer) {
-                memmove(s->proc_kmsg_buffer, p, remaining);
-                s->proc_kmsg_length = remaining;
-        }
-}
-
 static int system_journal_open(Server *s) {
         int r;
         char *fn;
@@ -2153,17 +2145,24 @@ finish:
         return r;
 }
 
-static int server_read_proc_kmsg(Server *s) {
+static int server_read_dev_kmsg(Server *s) {
+        char buffer[8192+1]; /* the kernel-side limit per record is 8K currently */
         ssize_t l;
+
         assert(s);
-        assert(s->proc_kmsg_fd >= 0);
+        assert(s->dev_kmsg_fd >= 0);
 
-        l = read(s->proc_kmsg_fd, s->proc_kmsg_buffer + s->proc_kmsg_length, sizeof(s->proc_kmsg_buffer) - 1 - s->proc_kmsg_length);
-        if (l == 0) /* the kernel is stupid and in some race
-                     * conditions returns 0 in the middle of the
-                     * stream. */
+        l = read(s->dev_kmsg_fd, buffer, sizeof(buffer) - 1);
+        if (l == 0)
                 return 0;
         if (l < 0) {
+                /* Old kernels who don't allow reading from /dev/kmsg
+                 * return EINVAL when we try. So handle this cleanly,
+                 * but don' try to ever read from it again. */
+                if (errno == EINVAL) {
+                        epoll_ctl(s->epoll_fd, EPOLL_CTL_DEL, s->dev_kmsg_fd, NULL);
+                        return 0;
+                }
 
                 if (errno == EAGAIN || errno == EINTR)
                         return 0;
@@ -2172,24 +2171,25 @@ static int server_read_proc_kmsg(Server *s) {
                 return -errno;
         }
 
-        s->proc_kmsg_length += l;
-
-        proc_kmsg_scan(s);
+        dev_kmsg_record(s, buffer, l);
         return 1;
 }
 
-static int server_flush_proc_kmsg(Server *s) {
+static int server_flush_dev_kmsg(Server *s) {
         int r;
 
         assert(s);
 
-        if (s->proc_kmsg_fd < 0)
+        if (s->dev_kmsg_fd < 0)
                 return 0;
 
-        log_info("Flushing /proc/kmsg...");
+        if (!s->dev_kmsg_readable)
+                return 0;
+
+        log_info("Flushing /dev/kmsg...");
 
         for (;;) {
-                r = server_read_proc_kmsg(s);
+                r = server_read_dev_kmsg(s);
                 if (r < 0)
                         return r;
 
@@ -2241,7 +2241,7 @@ static int process_event(Server *s, struct epoll_event *ev) {
 
                 return 0;
 
-        } else if (ev->data.fd == s->proc_kmsg_fd) {
+        } else if (ev->data.fd == s->dev_kmsg_fd) {
                 int r;
 
                 if (ev->events != EPOLLIN) {
@@ -2249,7 +2249,7 @@ static int process_event(Server *s, struct epoll_event *ev) {
                         return -EIO;
                 }
 
-                r = server_read_proc_kmsg(s);
+                r = server_read_dev_kmsg(s);
                 if (r < 0)
                         return r;
 
@@ -2594,28 +2594,68 @@ static int open_stdout_socket(Server *s) {
         return 0;
 }
 
-static int open_proc_kmsg(Server *s) {
+static int open_dev_kmsg(Server *s) {
         struct epoll_event ev;
 
         assert(s);
 
-        if (!s->import_proc_kmsg)
-                return 0;
-
-        s->proc_kmsg_fd = open("/proc/kmsg", O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
-        if (s->proc_kmsg_fd < 0) {
-                log_warning("Failed to open /proc/kmsg, ignoring: %m");
+        s->dev_kmsg_fd = open("/dev/kmsg", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
+        if (s->dev_kmsg_fd < 0) {
+                log_warning("Failed to open /dev/kmsg, ignoring: %m");
                 return 0;
         }
 
         zero(ev);
         ev.events = EPOLLIN;
-        ev.data.fd = s->proc_kmsg_fd;
-        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->proc_kmsg_fd, &ev) < 0) {
-                log_error("Failed to add /proc/kmsg fd to epoll object: %m");
+        ev.data.fd = s->dev_kmsg_fd;
+        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->dev_kmsg_fd, &ev) < 0) {
+
+                /* This will fail with EPERM on older kernels where
+                 * /dev/kmsg is not readable. */
+                if (errno == EPERM)
+                        return 0;
+
+                log_error("Failed to add /dev/kmsg fd to epoll object: %m");
                 return -errno;
         }
 
+        s->dev_kmsg_readable = true;
+
+        return 0;
+}
+
+static int open_kernel_seqnum(Server *s) {
+        int fd;
+        uint64_t *p;
+
+        assert(s);
+
+        /* We store the seqnum we last read in an mmaped file. That
+         * way we can just use it like a variable, but it is
+         * persistant and automatically flushed at reboot. */
+
+        fd = open("/run/systemd/journal/kernel-seqnum", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0644);
+        if (fd < 0) {
+                log_error("Failed to open /run/systemd/journal/kernel-seqnum, ignoring: %m");
+                return 0;
+        }
+
+        if (posix_fallocate(fd, 0, sizeof(uint64_t)) < 0) {
+                log_error("Failed to allocate sequential number file, ignoring: %m");
+                close_nointr_nofail(fd);
+                return 0;
+        }
+
+        p = mmap(NULL, sizeof(uint64_t), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+        if (p == MAP_FAILED) {
+                log_error("Failed to map sequential number file, ignoring: %m");
+                close_nointr_nofail(fd);
+                return 0;
+        }
+
+        close_nointr_nofail(fd);
+        s->kernel_seqnum = p;
+
         return 0;
 }
 
@@ -2733,7 +2773,7 @@ static int server_init(Server *s) {
         assert(s);
 
         zero(*s);
-        s->syslog_fd = s->native_fd = s->stdout_fd = s->signal_fd = s->epoll_fd = s->proc_kmsg_fd = -1;
+        s->syslog_fd = s->native_fd = s->stdout_fd = s->signal_fd = s->epoll_fd = s->dev_kmsg_fd = -1;
         s->compress = true;
 
         s->rate_limit_interval = DEFAULT_RATE_LIMIT_INTERVAL;
@@ -2752,11 +2792,11 @@ static int server_init(Server *s) {
         server_parse_config_file(s);
         server_parse_proc_cmdline(s);
 
+        mkdir_p("/run/systemd/journal", 0755);
+
         s->user_journals = hashmap_new(trivial_hash_func, trivial_compare_func);
-        if (!s->user_journals) {
-                log_error("Out of memory.");
-                return -ENOMEM;
-        }
+        if (!s->user_journals)
+                return log_oom();
 
         s->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
         if (s->epoll_fd < 0) {
@@ -2817,7 +2857,11 @@ static int server_init(Server *s) {
         if (r < 0)
                 return r;
 
-        r = open_proc_kmsg(s);
+        r = open_dev_kmsg(s);
+        if (r < 0)
+                return r;
+
+        r = open_kernel_seqnum(s);
         if (r < 0)
                 return r;
 
@@ -2869,12 +2913,15 @@ static void server_done(Server *s) {
         if (s->stdout_fd >= 0)
                 close_nointr_nofail(s->stdout_fd);
 
-        if (s->proc_kmsg_fd >= 0)
-                close_nointr_nofail(s->proc_kmsg_fd);
+        if (s->dev_kmsg_fd >= 0)
+                close_nointr_nofail(s->dev_kmsg_fd);
 
         if (s->rate_limit)
                 journal_rate_limit_free(s->rate_limit);
 
+        if (s->kernel_seqnum)
+                munmap(s->kernel_seqnum, sizeof(uint64_t));
+
         free(s->buffer);
         free(s->tty_path);
 }
@@ -2906,7 +2953,7 @@ int main(int argc, char *argv[]) {
 
         server_vacuum(&server);
         server_flush_to_var(&server);
-        server_flush_proc_kmsg(&server);
+        server_flush_dev_kmsg(&server);
 
         log_debug("systemd-journald running as pid %lu", (unsigned long) getpid());
         driver_message(&server, SD_MESSAGE_JOURNAL_START, "Journal started");