d682b3a7e7
Always cache the results, and bypass low-level security calls when the respective subsystem is not enabled.
433 lines
15 KiB
C
433 lines
15 KiB
C
/*-*- 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 Lesser General Public License as published by
|
|
the Free Software Foundation; either version 2.1 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
|
***/
|
|
|
|
#include <unistd.h>
|
|
#include <stddef.h>
|
|
#include <sys/epoll.h>
|
|
|
|
#include "socket-util.h"
|
|
#include "path-util.h"
|
|
#include "selinux-util.h"
|
|
#include "journald-server.h"
|
|
#include "journald-native.h"
|
|
#include "journald-kmsg.h"
|
|
#include "journald-console.h"
|
|
#include "journald-syslog.h"
|
|
|
|
/* Make sure not to make this smaller than the maximum coredump
|
|
* size. See COREDUMP_MAX in coredump.c */
|
|
#define ENTRY_SIZE_MAX (1024*1024*768)
|
|
#define DATA_SIZE_MAX (1024*1024*768)
|
|
|
|
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 bool allow_object_pid(struct ucred *ucred) {
|
|
return ucred && ucred->uid == 0;
|
|
}
|
|
|
|
void server_process_native_message(
|
|
Server *s,
|
|
const void *buffer, size_t buffer_size,
|
|
struct ucred *ucred,
|
|
struct timeval *tv,
|
|
const char *label, size_t label_len) {
|
|
|
|
struct iovec *iovec = NULL;
|
|
unsigned n = 0, j, tn = (unsigned) -1;
|
|
const char *p;
|
|
size_t remaining, m = 0;
|
|
int priority = LOG_INFO;
|
|
char *identifier = NULL, *message = NULL;
|
|
pid_t object_pid = 0;
|
|
|
|
assert(s);
|
|
assert(buffer || buffer_size == 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 */
|
|
server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid);
|
|
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 */
|
|
|
|
/* n received properties, +1 for _TRANSPORT */
|
|
if (!GREEDY_REALLOC(iovec, m, n + 1 + N_IOVEC_META_FIELDS +
|
|
!!object_pid * N_IOVEC_OBJECT_FIELDS)) {
|
|
log_oom();
|
|
break;
|
|
}
|
|
|
|
q = memchr(p, '=', e - p);
|
|
if (q) {
|
|
if (valid_user_field(p, q - p)) {
|
|
size_t l;
|
|
|
|
l = e - 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 = l;
|
|
n++;
|
|
|
|
/* We need to determine the priority
|
|
* of this entry for the rate limiting
|
|
* logic */
|
|
if (l == 10 &&
|
|
startswith(p, "PRIORITY=") &&
|
|
p[9] >= '0' && p[9] <= '9')
|
|
priority = (priority & LOG_FACMASK) | (p[9] - '0');
|
|
|
|
else if (l == 17 &&
|
|
startswith(p, "SYSLOG_FACILITY=") &&
|
|
p[16] >= '0' && p[16] <= '9')
|
|
priority = (priority & LOG_PRIMASK) | ((p[16] - '0') << 3);
|
|
|
|
else if (l == 18 &&
|
|
startswith(p, "SYSLOG_FACILITY=") &&
|
|
p[16] >= '0' && p[16] <= '9' &&
|
|
p[17] >= '0' && p[17] <= '9')
|
|
priority = (priority & LOG_PRIMASK) | (((p[16] - '0')*10 + (p[17] - '0')) << 3);
|
|
|
|
else if (l >= 19 &&
|
|
startswith(p, "SYSLOG_IDENTIFIER=")) {
|
|
char *t;
|
|
|
|
t = strndup(p + 18, l - 18);
|
|
if (t) {
|
|
free(identifier);
|
|
identifier = t;
|
|
}
|
|
} else if (l >= 8 &&
|
|
startswith(p, "MESSAGE=")) {
|
|
char *t;
|
|
|
|
t = strndup(p + 8, l - 8);
|
|
if (t) {
|
|
free(message);
|
|
message = t;
|
|
}
|
|
} else if (l > strlen("OBJECT_PID=") &&
|
|
l < strlen("OBJECT_PID=") + DECIMAL_STR_MAX(pid_t) &&
|
|
startswith(p, "OBJECT_PID=") &&
|
|
allow_object_pid(ucred)) {
|
|
char buf[DECIMAL_STR_MAX(pid_t)];
|
|
memcpy(buf, p + strlen("OBJECT_PID="), l - strlen("OBJECT_PID="));
|
|
char_array_0(buf);
|
|
|
|
/* ignore error */
|
|
parse_pid(buf, &object_pid);
|
|
}
|
|
}
|
|
|
|
remaining -= (e - p) + 1;
|
|
p = e + 1;
|
|
continue;
|
|
} else {
|
|
le64_t l_le;
|
|
uint64_t l;
|
|
char *k;
|
|
|
|
if (remaining < e - p + 1 + sizeof(uint64_t) + 1) {
|
|
log_debug("Failed to parse message, ignoring.");
|
|
break;
|
|
}
|
|
|
|
memcpy(&l_le, e + 1, sizeof(uint64_t));
|
|
l = le64toh(l_le);
|
|
|
|
if (l > DATA_SIZE_MAX) {
|
|
log_debug("Received binary data block too large, ignoring.");
|
|
break;
|
|
}
|
|
|
|
if ((uint64_t) 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_oom();
|
|
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;
|
|
}
|
|
}
|
|
|
|
if (n <= 0)
|
|
goto finish;
|
|
|
|
tn = n++;
|
|
IOVEC_SET_STRING(iovec[tn], "_TRANSPORT=journal");
|
|
|
|
if (message) {
|
|
if (s->forward_to_syslog)
|
|
server_forward_syslog(s, priority, identifier, message, ucred, tv);
|
|
|
|
if (s->forward_to_kmsg)
|
|
server_forward_kmsg(s, priority, identifier, message, ucred);
|
|
|
|
if (s->forward_to_console)
|
|
server_forward_console(s, priority, identifier, message, ucred);
|
|
}
|
|
|
|
server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid);
|
|
|
|
finish:
|
|
for (j = 0; j < n; j++) {
|
|
if (j == tn)
|
|
continue;
|
|
|
|
if (iovec[j].iov_base < buffer ||
|
|
(const uint8_t*) iovec[j].iov_base >= (const uint8_t*) buffer + buffer_size)
|
|
free(iovec[j].iov_base);
|
|
}
|
|
|
|
free(iovec);
|
|
free(identifier);
|
|
free(message);
|
|
}
|
|
|
|
void server_process_native_file(
|
|
Server *s,
|
|
int fd,
|
|
struct ucred *ucred,
|
|
struct timeval *tv,
|
|
const char *label, size_t label_len) {
|
|
|
|
struct stat st;
|
|
_cleanup_free_ void *p = NULL;
|
|
ssize_t n;
|
|
int r;
|
|
|
|
assert(s);
|
|
assert(fd >= 0);
|
|
|
|
if (!ucred || ucred->uid != 0) {
|
|
_cleanup_free_ char *sl = NULL, *k = NULL;
|
|
const char *e;
|
|
|
|
if (asprintf(&sl, "/proc/self/fd/%i", fd) < 0) {
|
|
log_oom();
|
|
return;
|
|
}
|
|
|
|
r = readlink_malloc(sl, &k);
|
|
if (r < 0) {
|
|
log_error("readlink(%s) failed: %m", sl);
|
|
return;
|
|
}
|
|
|
|
e = path_startswith(k, "/dev/shm/");
|
|
if (!e)
|
|
e = path_startswith(k, "/tmp/");
|
|
if (!e)
|
|
e = path_startswith(k, "/var/tmp/");
|
|
if (!e) {
|
|
log_error("Received file outside of allowed directories. Refusing.");
|
|
return;
|
|
}
|
|
|
|
if (!filename_is_safe(e)) {
|
|
log_error("Received file in subdirectory of allowed directories. Refusing.");
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* Data is in the passed file, since it didn't fit in a
|
|
* datagram. We can't map the file here, since clients might
|
|
* then truncate it and trigger a SIGBUS for us. So let's
|
|
* stupidly read it */
|
|
|
|
if (fstat(fd, &st) < 0) {
|
|
log_error("Failed to stat passed file, ignoring: %m");
|
|
return;
|
|
}
|
|
|
|
if (!S_ISREG(st.st_mode)) {
|
|
log_error("File passed is not regular. Ignoring.");
|
|
return;
|
|
}
|
|
|
|
if (st.st_size <= 0)
|
|
return;
|
|
|
|
if (st.st_size > ENTRY_SIZE_MAX) {
|
|
log_error("File passed too large. Ignoring.");
|
|
return;
|
|
}
|
|
|
|
p = malloc(st.st_size);
|
|
if (!p) {
|
|
log_oom();
|
|
return;
|
|
}
|
|
|
|
n = pread(fd, p, st.st_size, 0);
|
|
if (n < 0)
|
|
log_error("Failed to read file, ignoring: %s", strerror(-n));
|
|
else if (n > 0)
|
|
server_process_native_message(s, p, n, ucred, tv, label, label_len);
|
|
}
|
|
|
|
int server_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|SOCK_NONBLOCK, 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/socket", 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);
|
|
} else
|
|
fd_nonblock(s->native_fd, 1);
|
|
|
|
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;
|
|
}
|
|
|
|
#ifdef HAVE_SELINUX
|
|
if (use_selinux()) {
|
|
one = 1;
|
|
r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one));
|
|
if (r < 0)
|
|
log_warning("SO_PASSSEC failed: %m");
|
|
}
|
|
#endif
|
|
|
|
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;
|
|
}
|