84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering

b5efdb8af40ea759a1ea584c1bc44ecc81dd00ceLennart Poettering#include <unistd.h>

3ffd4af22052963e7a29431721ee204e634bea75Lennart Poettering#include <sys/epoll.h>

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering#include <fcntl.h>

3ffd4af22052963e7a29431721ee204e634bea75Lennart Poettering#include <sys/mman.h>

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering#include <sys/socket.h>

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering#include <systemd/sd-messages.h>

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering#include <libudev.h>

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering#include "journald-server.h"

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering#include "journald-kmsg.h"

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering#include "journald-syslog.h"

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poetteringvoid server_forward_kmsg(

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering Server *s,

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering int priority,

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering const char *identifier,

84e51726a38e133ca42d2f30f0668d3921b210cbLennart Poettering const char *message,

struct ucred *ucred) {

struct iovec iovec[5];

char header_priority[6], header_pid[16];

int n = 0;

char *ident_buf = NULL;

assert(s);

assert(priority >= 0);

assert(priority <= 999);

assert(message);

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

priority = syslog_fixup_facility(priority);

/* First: priority field */

snprintf(header_priority, sizeof(header_priority), "<%i>", priority);

char_array_0(header_priority);

IOVEC_SET_STRING(iovec[n++], header_priority);

/* Second: identifier and PID */

if (ucred) {

if (!identifier) {

get_process_comm(ucred->pid, &ident_buf);

identifier = ident_buf;

}

snprintf(header_pid, sizeof(header_pid), "["PID_FMT"]: ", ucred->pid);

char_array_0(header_pid);

if (identifier)

IOVEC_SET_STRING(iovec[n++], identifier);

IOVEC_SET_STRING(iovec[n++], header_pid);

} else if (identifier) {

IOVEC_SET_STRING(iovec[n++], identifier);

IOVEC_SET_STRING(iovec[n++], ": ");

}

/* Fourth: message */

IOVEC_SET_STRING(iovec[n++], message);

IOVEC_SET_STRING(iovec[n++], "\n");

if (writev(s->dev_kmsg_fd, iovec, n) < 0)

log_debug("Failed to write to /dev/kmsg for logging: %m");

free(ident_buf);

}

static bool is_us(const char *pid) {

pid_t t;

assert(pid);

if (parse_pid(pid, &t) < 0)

return false;

return t == getpid();

}

static void dev_kmsg_record(Server *s, char *p, size_t l) {

struct iovec iovec[N_IOVEC_META_FIELDS + 7 + N_IOVEC_KERNEL_FIELDS + 2 + N_IOVEC_UDEV_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;

unsigned long long usec;

char *identifier = NULL, *pid = NULL, *e, *f, *k;

uint64_t serial;

size_t pl;

char *kernel_device = NULL;

assert(s);

assert(p);

if (l <= 0)

return;

e = memchr(p, ',', l);

if (!e)

return;

*e = 0;

r = safe_atoi(p, &priority);

if (r < 0 || priority < 0 || priority > 999)

return;

if (s->forward_to_kmsg && (priority & LOG_FACMASK) != LOG_KERN)

return;

l -= (e - p) + 1;

p = e + 1;

e = memchr(p, ',', l);

if (!e)

return;

*e = 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;

/* Did we lose any? */

if (serial > *s->kernel_seqnum)

server_driver_message(s, SD_MESSAGE_JOURNAL_MISSED, "Missed %"PRIu64" kernel messages",

serial - *s->kernel_seqnum - 1);

/* Make sure we never read this one again. Note that

*s->kernel_seqnum = serial + 1;

}

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;

r = safe_atollu(p, &usec);

if (r < 0)

return;

l -= (f - p) + 1;

p = f + 1;

e = memchr(p, '\n', l);

if (!e)

return;

*e = 0;

pl = e - p;

l -= (e - p) + 1;

k = e + 1;

for (j = 0; l > 0 && j < N_IOVEC_KERNEL_FIELDS; j++) {

char *m;

/* Meta data fields attached */

if (*k != ' ')

break;

k ++, l --;

e = memchr(k, '\n', l);

if (!e)

return;

*e = 0;

m = cunescape_length_with_prefix(k, e - k, "_KERNEL_");

if (!m)

break;

if (startswith(m, "_KERNEL_DEVICE="))

kernel_device = m + 15;

IOVEC_SET_STRING(iovec[n++], m);

z++;

l -= (e - k) + 1;

k = e + 1;

}

if (kernel_device) {

struct udev_device *ud;

ud = udev_device_new_from_device_id(s->udev, kernel_device);

if (ud) {

const char *g;

struct udev_list_entry *ll;

char *b;

g = udev_device_get_devnode(ud);

if (g) {

b = strappend("_UDEV_DEVNODE=", g);

if (b) {

IOVEC_SET_STRING(iovec[n++], b);

z++;

}

}

g = udev_device_get_sysname(ud);

if (g) {

b = strappend("_UDEV_SYSNAME=", g);

if (b) {

IOVEC_SET_STRING(iovec[n++], b);

z++;

}

}

j = 0;

ll = udev_device_get_devlinks_list_entry(ud);

udev_list_entry_foreach(ll, ll) {

if (j > N_IOVEC_UDEV_FIELDS)

break;

g = udev_list_entry_get_name(ll);

if (g) {

b = strappend("_UDEV_DEVLINK=", g);

if (b) {

IOVEC_SET_STRING(iovec[n++], b);

z++;

}

}

j++;

}

udev_device_unref(ud);

}

}

if (asprintf(&source_time, "_SOURCE_MONOTONIC_TIMESTAMP=%llu", 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 (asprintf(&syslog_facility, "SYSLOG_FACILITY=%i", LOG_FAC(priority)) >= 0)

IOVEC_SET_STRING(iovec[n++], syslog_facility);

if ((priority & LOG_FACMASK) == LOG_KERN)

IOVEC_SET_STRING(iovec[n++], "SYSLOG_IDENTIFIER=kernel");

else {

pl -= syslog_parse_identifier((const char**) &p, &identifier, &pid);

/* Avoid any messages we generated ourselves via

if (pid && is_us(pid))

goto finish;

if (identifier) {

syslog_identifier = strappend("SYSLOG_IDENTIFIER=", identifier);

if (syslog_identifier)

IOVEC_SET_STRING(iovec[n++], syslog_identifier);

}

if (pid) {

syslog_pid = strappend("SYSLOG_PID=", pid);

if (syslog_pid)

IOVEC_SET_STRING(iovec[n++], syslog_pid);

}

}

message = cunescape_length_with_prefix(p, pl, "MESSAGE=");

if (message)

IOVEC_SET_STRING(iovec[n++], message);

server_dispatch_message(s, iovec, n, ELEMENTSOF(iovec), NULL, NULL, NULL, 0, NULL, priority, 0);

finish:

for (j = 0; j < z; j++)

free(iovec[j].iov_base);

free(message);

free(syslog_priority);

free(syslog_identifier);

free(syslog_pid);

free(syslog_facility);

free(source_time);

free(identifier);

free(pid);

}

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->dev_kmsg_fd >= 0);

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

if (errno == EINVAL) {

s->dev_kmsg_event_source = sd_event_source_unref(s->dev_kmsg_event_source);

return 0;

}

if (errno == EAGAIN || errno == EINTR || errno == EPIPE)

return 0;

log_error("Failed to read from kernel: %m");

return -errno;

}

dev_kmsg_record(s, buffer, l);

return 1;

}

int server_flush_dev_kmsg(Server *s) {

int r;

assert(s);

if (s->dev_kmsg_fd < 0)

return 0;

if (!s->dev_kmsg_readable)

return 0;

log_debug("Flushing /dev/kmsg...");

for (;;) {

r = server_read_dev_kmsg(s);

if (r < 0)

return r;

if (r == 0)

break;

}

return 0;

}

static int dispatch_dev_kmsg(sd_event_source *es, int fd, uint32_t revents, void *userdata) {

Server *s = userdata;

assert(es);

assert(fd == s->dev_kmsg_fd);

assert(s);

if (revents & EPOLLERR)

log_warning("/dev/kmsg buffer overrun, some messages lost.");

if (!(revents & EPOLLIN))

log_error("Got invalid event from epoll for /dev/kmsg: %"PRIx32, revents);

return server_read_dev_kmsg(s);

}

int server_open_dev_kmsg(Server *s) {

int r;

assert(s);

s->dev_kmsg_fd = open("/dev/kmsg", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);

if (s->dev_kmsg_fd < 0) {

log_full(errno == ENOENT ? LOG_DEBUG : LOG_WARNING,

"Failed to open /dev/kmsg, ignoring: %m");

return 0;

}

r = sd_event_add_io(s->event, &s->dev_kmsg_event_source, s->dev_kmsg_fd, EPOLLIN, dispatch_dev_kmsg, s);

if (r < 0) {

/* This will fail with EPERM on older kernels where

if (r == -EPERM) {

r = 0;

goto fail;

}

log_error("Failed to add /dev/kmsg fd to event loop: %s", strerror(-r));

goto fail;

}

r = sd_event_source_set_priority(s->dev_kmsg_event_source, SD_EVENT_PRIORITY_IMPORTANT+10);

if (r < 0) {

log_error("Failed to adjust priority of kmsg event source: %s", strerror(-r));

goto fail;

}

s->dev_kmsg_readable = true;

return 0;

fail:

s->dev_kmsg_event_source = sd_event_source_unref(s->dev_kmsg_event_source);

s->dev_kmsg_fd = safe_close(s->dev_kmsg_fd);

return r;

}

int server_open_kernel_seqnum(Server *s) {

_cleanup_close_ int fd;

uint64_t *p;

assert(s);

/* We store the seqnum we last read in an mmaped file. That

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");

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");

return 0;

}

s->kernel_seqnum = p;

return 0;

}