/src/systemd/src/journal/journald-kmsg.c

Source (jump to first uncovered line)
/* SPDX-License-Identifier: LGPL-2.1+ */

#include <fcntl.h>
#include <sys/epoll.h>
#include <sys/mman.h>
#include <sys/socket.h>
#include <unistd.h>

#include "sd-device.h"
#include "sd-messages.h"

#include "alloc-util.h"
#include "device-util.h"
#include "escape.h"
#include "fd-util.h"
#include "format-util.h"
#include "io-util.h"
#include "journald-kmsg.h"
#include "journald-server.h"
#include "journald-syslog.h"
#include "parse-util.h"
#include "process-util.h"
#include "stdio-util.h"
#include "string-util.h"

void server_forward_kmsg(
        Server *s,
        int priority,
        const char *identifier,
        const char *message,
        const struct ucred *ucred) {

        _cleanup_free_ char *ident_buf = NULL;
        struct iovec iovec[5];
        char header_priority[DECIMAL_STR_MAX(priority) + 3],
             header_pid[STRLEN("[]: ") + DECIMAL_STR_MAX(pid_t) + 1];
        int n = 0;

        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
         * kmsg, regardless where the data comes from. */
        priority = syslog_fixup_facility(priority);

        /* First: priority field */
        xsprintf(header_priority, "<%i>", priority);
        iovec[n++] = IOVEC_MAKE_STRING(header_priority);

        /* Second: identifier and PID */
        if (ucred) {
                if (!identifier) {
                        get_process_comm(ucred->pid, &ident_buf);
                        identifier = ident_buf;
                }

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

                if (identifier)
                        iovec[n++] = IOVEC_MAKE_STRING(identifier);

                iovec[n++] = IOVEC_MAKE_STRING(header_pid);
        } else if (identifier) {
                iovec[n++] = IOVEC_MAKE_STRING(identifier);
                iovec[n++] = IOVEC_MAKE_STRING(": ");
        }

        /* Fourth: message */
        iovec[n++] = IOVEC_MAKE_STRING(message);
        iovec[n++] = IOVEC_MAKE_STRING("\n");

        if (writev(s->dev_kmsg_fd, iovec, n) < 0)
                log_debug_errno(errno, "Failed to write to /dev/kmsg for logging: %m");
}

static bool is_us(const char *identifier, const char *pid) {
        pid_t pid_num;

        if (!identifier || !pid)
                return false;

        if (parse_pid(pid, &pid_num) < 0)
                return false;

        return pid_num == getpid_cached() &&
               streq(identifier, program_invocation_short_name);
}

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

        _cleanup_free_ char *message = NULL, *syslog_priority = NULL, *syslog_pid = NULL, *syslog_facility = NULL, *syslog_identifier = NULL, *source_time = NULL, *identifier = NULL, *pid = NULL;
        struct iovec iovec[N_IOVEC_META_FIELDS + 7 + N_IOVEC_KERNEL_FIELDS + 2 + N_IOVEC_UDEV_FIELDS];
        char *kernel_device = NULL;
        unsigned long long usec;
        size_t n = 0, z = 0, j;
        int priority, r;
        char *e, *f, *k;
        uint64_t serial;
        size_t pl;

        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 && LOG_FAC(priority) != 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, 0,
                                              "MESSAGE_ID=" SD_MESSAGE_JOURNAL_MISSED_STR,
                                              LOG_MESSAGE("Missed %"PRIu64" kernel messages",
                                                          serial - *s->kernel_seqnum),
                                              NULL);

                /* 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;
        }

        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;
                /* Metadata fields attached */

                if (*k != ' ')
                        break;

                k++, l--;

                e = memchr(k, '\n', l);
                if (!e)
                        goto finish;

                *e = 0;

                if (cunescape_length_with_prefix(k, e - k, "_KERNEL_", UNESCAPE_RELAX, &m) < 0)
                        break;

                if (startswith(m, "_KERNEL_DEVICE="))
                        kernel_device = m + 15;

                iovec[n++] = IOVEC_MAKE_STRING(m);
                z++;

                l -= (e - k) + 1;
                k = e + 1;
        }

        if (kernel_device) {
                _cleanup_(sd_device_unrefp) sd_device *d = NULL;

                if (sd_device_new_from_device_id(&d, kernel_device) >= 0) {
                        const char *g;
                        char *b;

                        if (sd_device_get_devname(d, &g) >= 0) {
                                b = strappend("_UDEV_DEVNODE=", g);
                                if (b) {
                                        iovec[n++] = IOVEC_MAKE_STRING(b);
                                        z++;
                                }
                        }

                        if (sd_device_get_sysname(d, &g) >= 0) {
                                b = strappend("_UDEV_SYSNAME=", g);
                                if (b) {
                                        iovec[n++] = IOVEC_MAKE_STRING(b);
                                        z++;
                                }
                        }

                        j = 0;
                        FOREACH_DEVICE_DEVLINK(d, g) {

                                if (j >= N_IOVEC_UDEV_FIELDS)
                                        break;

                                b = strappend("_UDEV_DEVLINK=", g);
                                if (b) {
                                        iovec[n++] = IOVEC_MAKE_STRING(b);
                                        z++;
                                }

                                j++;
                        }
                }
        }

        if (asprintf(&source_time, "_SOURCE_MONOTONIC_TIMESTAMP=%llu", usec) >= 0)
                iovec[n++] = IOVEC_MAKE_STRING(source_time);

        iovec[n++] = IOVEC_MAKE_STRING("_TRANSPORT=kernel");

        if (asprintf(&syslog_priority, "PRIORITY=%i", priority & LOG_PRIMASK) >= 0)
                iovec[n++] = IOVEC_MAKE_STRING(syslog_priority);

        if (asprintf(&syslog_facility, "SYSLOG_FACILITY=%i", LOG_FAC(priority)) >= 0)
                iovec[n++] = IOVEC_MAKE_STRING(syslog_facility);

        if (LOG_FAC(priority) == LOG_KERN)
                iovec[n++] = IOVEC_MAKE_STRING("SYSLOG_IDENTIFIER=kernel");
        else {
                pl -= syslog_parse_identifier((const char**) &p, &identifier, &pid);

                /* Avoid any messages we generated ourselves via
                 * log_info() and friends. */
                if (is_us(identifier, pid))
                        goto finish;

                if (identifier) {
                        syslog_identifier = strappend("SYSLOG_IDENTIFIER=", identifier);
                        if (syslog_identifier)
                                iovec[n++] = IOVEC_MAKE_STRING(syslog_identifier);
                }

                if (pid) {
                        syslog_pid = strappend("SYSLOG_PID=", pid);
                        if (syslog_pid)
                                iovec[n++] = IOVEC_MAKE_STRING(syslog_pid);
                }
        }

        if (cunescape_length_with_prefix(p, pl, "MESSAGE=", UNESCAPE_RELAX, &message) >= 0)
                iovec[n++] = IOVEC_MAKE_STRING(message);

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

finish:
        for (j = 0; j < z; j++)
                free(iovec[j].iov_base);
}

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
                 * return EINVAL when we try. So handle this cleanly,
                 * but don' try to ever read from it again. */
                if (errno == EINVAL) {
                        s->dev_kmsg_event_source = sd_event_source_unref(s->dev_kmsg_event_source);
                        return 0;
                }

                if (IN_SET(errno, EAGAIN, EINTR, EPIPE))
                        return 0;

                return log_error_errno(errno, "Failed to read from kernel: %m");
        }

        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) {
        mode_t mode;
        int r;

        assert(s);

        if (s->read_kmsg)
                mode = O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY;
        else
                mode = O_WRONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY;

        s->dev_kmsg_fd = open("/dev/kmsg", mode);
        if (s->dev_kmsg_fd < 0) {
                log_full(errno == ENOENT ? LOG_DEBUG : LOG_WARNING,
                         "Failed to open /dev/kmsg, ignoring: %m");
                return 0;
        }

        if (!s->read_kmsg)
                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
                 * /dev/kmsg is not readable. */
                if (r == -EPERM) {
                        r = 0;
                        goto fail;
                }

                log_error_errno(r, "Failed to add /dev/kmsg fd to event loop: %m");
                goto fail;
        }

        r = sd_event_source_set_priority(s->dev_kmsg_event_source, SD_EVENT_PRIORITY_IMPORTANT+10);
        if (r < 0) {
                log_error_errno(r, "Failed to adjust priority of kmsg event source: %m");
                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;
        int r;

        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
         * persistent 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_errno(errno, "Failed to open /run/systemd/journal/kernel-seqnum, ignoring: %m");
                return 0;
        }

        r = posix_fallocate(fd, 0, sizeof(uint64_t));
        if (r != 0) {
                log_error_errno(r, "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_errno(errno, "Failed to map sequential number file, ignoring: %m");
                return 0;
        }

        s->kernel_seqnum = p;

        return 0;
}

Coverage Report

Created: 2019-06-19 13:33

Line	Count	Source (jump to first uncovered line)
1		/* SPDX-License-Identifier: LGPL-2.1+ */
2
3		#include <fcntl.h>
4		#include <sys/epoll.h>
5		#include <sys/mman.h>
6		#include <sys/socket.h>
7		#include <unistd.h>
8
9		#include "sd-device.h"
10		#include "sd-messages.h"
11
12		#include "alloc-util.h"
13		#include "device-util.h"
14		#include "escape.h"
15		#include "fd-util.h"
16		#include "format-util.h"
17		#include "io-util.h"
18		#include "journald-kmsg.h"
19		#include "journald-server.h"
20		#include "journald-syslog.h"
21		#include "parse-util.h"
22		#include "process-util.h"
23		#include "stdio-util.h"
24		#include "string-util.h"
25
26		void server_forward_kmsg(
27		Server *s,
28		int priority,
29		const char *identifier,
30		const char *message,
31	962k	const struct ucred *ucred) {
32	962k
33	962k	_cleanup_free_ char *ident_buf = NULL;
34	962k	struct iovec iovec[5];
35	962k	char header_priority[DECIMAL_STR_MAX(priority) + 3],
36	962k	header_pid[STRLEN("[]: ") + DECIMAL_STR_MAX(pid_t) + 1];
37	962k	int n = 0;
38	962k
39	962k	assert(s);
40	962k	assert(priority >= 0);
41	962k	assert(priority <= 999);
42	962k	assert(message);
43	962k
44	962k	if (_unlikely_(LOG_PRI(priority) > s->max_level_kmsg))
45	962k	return;
46	955k
47	955k	if (_unlikely_(s->dev_kmsg_fd < 0))
48	955k	return;
49	0
50	0	/* Never allow messages with kernel facility to be written to
51	0	* kmsg, regardless where the data comes from. */
52	0	priority = syslog_fixup_facility(priority);
53	0
54	0	/* First: priority field */
55	0	xsprintf(header_priority, "<%i>", priority);
56	0	iovec[n++] = IOVEC_MAKE_STRING(header_priority);
57	0
58	0	/* Second: identifier and PID */
59	0	if (ucred) {
60	0	if (!identifier) {
61	0	get_process_comm(ucred->pid, &ident_buf);
62	0	identifier = ident_buf;
63	0	}
64	0
65	0	xsprintf(header_pid, "["PID_FMT"]: ", ucred->pid);
66	0
67	0	if (identifier)
68	0	iovec[n++] = IOVEC_MAKE_STRING(identifier);
69	0
70	0	iovec[n++] = IOVEC_MAKE_STRING(header_pid);
71	0	} else if (identifier) {
72	0	iovec[n++] = IOVEC_MAKE_STRING(identifier);
73	0	iovec[n++] = IOVEC_MAKE_STRING(": ");
74	0	}
75	0
76	0	/* Fourth: message */
77	0	iovec[n++] = IOVEC_MAKE_STRING(message);
78	0	iovec[n++] = IOVEC_MAKE_STRING("\n");
79	0
80	0	if (writev(s->dev_kmsg_fd, iovec, n) < 0)
81	0	log_debug_errno(errno, "Failed to write to /dev/kmsg for logging: %m");
82	0	}
83
84	467	static bool is_us(const char identifier, const char pid) {
85	467	pid_t pid_num;
86	467
87	467	if (!identifier \|\| !pid)
88	265	return false;
89	202
90	202	if (parse_pid(pid, &pid_num) < 0)
91	116	return false;
92	86
93	86	return pid_num == getpid_cached() &&
94	86	streq(identifier, program_invocation_short_name);
95	86	}
96
97	2.17k	void dev_kmsg_record(Server s, char p, size_t l) {
98	2.17k
99	2.17k	_cleanup_free_ char message = NULL, syslog_priority = NULL, syslog_pid = NULL, syslog_facility = NULL, syslog_identifier = NULL, source_time = NULL, identifier = NULL, pid = NULL;
100	2.17k	struct iovec iovec[N_IOVEC_META_FIELDS + 7 + N_IOVEC_KERNEL_FIELDS + 2 + N_IOVEC_UDEV_FIELDS];
101	2.17k	char *kernel_device = NULL;
102	2.17k	unsigned long long usec;
103	2.17k	size_t n = 0, z = 0, j;
104	2.17k	int priority, r;
105	2.17k	char e, f, *k;
106	2.17k	uint64_t serial;
107	2.17k	size_t pl;
108	2.17k
109	2.17k	assert(s);
110	2.17k	assert(p);
111	2.17k
112	2.17k	if (l <= 0)
113	0	return;
114	2.17k
115	2.17k	e = memchr(p, ',', l);
116	2.17k	if (!e)
117	14	return;
118	2.16k	*e = 0;
119	2.16k
120	2.16k	r = safe_atoi(p, &priority);
121	2.16k	if (r < 0 \|\| priority < 0 \|\| priority > 999)
122	176	return;
123	1.98k
124	1.98k	if (s->forward_to_kmsg && LOG_FAC(priority) != LOG_KERN)
125	1.98k	return;
126	1.98k
127	1.98k	l -= (e - p) + 1;
128	1.98k	p = e + 1;
129	1.98k	e = memchr(p, ',', l);
130	1.98k	if (!e)
131	22	return;
132	1.96k	*e = 0;
133	1.96k
134	1.96k	r = safe_atou64(p, &serial);
135	1.96k	if (r < 0)
136	11	return;
137	1.95k
138	1.95k	if (s->kernel_seqnum) {
139	0	/* We already read this one? */
140	0	if (serial < *s->kernel_seqnum)
141	0	return;
142	0
143	0	/* Did we lose any? */
144	0	if (serial > *s->kernel_seqnum)
145	0	server_driver_message(s, 0,
146	0	"MESSAGE_ID=" SD_MESSAGE_JOURNAL_MISSED_STR,
147	0	LOG_MESSAGE("Missed %"PRIu64" kernel messages",
148	0	serial - *s->kernel_seqnum),
149	0	NULL);
150	0
151	0	/* Make sure we never read this one again. Note that
152	0	* we always store the next message serial we expect
153	0	* here, simply because this makes handling the first
154	0	* message with serial 0 easy. */
155	0	*s->kernel_seqnum = serial + 1;
156	0	}
157	1.95k
158	1.95k	l -= (e - p) + 1;
159	1.95k	p = e + 1;
160	1.95k	f = memchr(p, ';', l);
161	1.95k	if (!f)
162	6	return;
163	1.94k	/* Kernel 3.6 has the flags field, kernel 3.5 lacks that */
164	1.94k	e = memchr(p, ',', l);
165	1.94k	if (!e \|\| f < e)
166	1.93k	e = f;
167	1.94k	*e = 0;
168	1.94k
169	1.94k	r = safe_atollu(p, &usec);
170	1.94k	if (r < 0)
171	4	return;
172	1.94k
173	1.94k	l -= (f - p) + 1;
174	1.94k	p = f + 1;
175	1.94k	e = memchr(p, '\n', l);
176	1.94k	if (!e)
177	1	return;
178	1.94k	*e = 0;
179	1.94k
180	1.94k	pl = e - p;
181	1.94k	l -= (e - p) + 1;
182	1.94k	k = e + 1;
183	1.94k
184	3.92k	for (j = 0; l > 0 && j < N_IOVEC_KERNEL_FIELDS; j++) {
185	2.03k	char *m;
186	2.03k	/* Metadata fields attached */
187	2.03k
188	2.03k	if (*k != ' ')
189	55	break;
190	1.98k
191	1.98k	k++, l--;
192	1.98k
193	1.98k	e = memchr(k, '\n', l);
194	1.98k	if (!e)
195	7	goto finish;
196	1.97k
197	1.97k	*e = 0;
198	1.97k
199	1.97k	if (cunescape_length_with_prefix(k, e - k, "_KERNEL_", UNESCAPE_RELAX, &m) < 0)
200	0	break;
201	1.97k
202	1.97k	if (startswith(m, "_KERNEL_DEVICE="))
203	839	kernel_device = m + 15;
204	1.97k
205	1.97k	iovec[n++] = IOVEC_MAKE_STRING(m);
206	1.97k	z++;
207	1.97k
208	1.97k	l -= (e - k) + 1;
209	1.97k	k = e + 1;
210	1.97k	}
211	1.94k
212	1.94k	if (kernel_device) {
213	767	_cleanup_(sd_device_unrefp) sd_device *d = NULL;
214	767
215	767	if (sd_device_new_from_device_id(&d, kernel_device) >= 0) {
216	16	const char *g;
217	16	char *b;
218	16
219	16	if (sd_device_get_devname(d, &g) >= 0) {
220	2	b = strappend("_UDEV_DEVNODE=", g);
221	2	if (b) {
222	2	iovec[n++] = IOVEC_MAKE_STRING(b);
223	2	z++;
224	2	}
225	2	}
226	16
227	16	if (sd_device_get_sysname(d, &g) >= 0) {
228	16	b = strappend("_UDEV_SYSNAME=", g);
229	16	if (b) {
230	16	iovec[n++] = IOVEC_MAKE_STRING(b);
231	16	z++;
232	16	}
233	16	}
234	16
235	16	j = 0;
236	16	FOREACH_DEVICE_DEVLINK(d, g) {
237	0
238	0	if (j >= N_IOVEC_UDEV_FIELDS)
239	0	break;
240	0
241	0	b = strappend("_UDEV_DEVLINK=", g);
242	0	if (b) {
243	0	iovec[n++] = IOVEC_MAKE_STRING(b);
244	0	z++;
245	0	}
246	0
247	0	j++;
248	0	}
249	16	}
250	767	}
251	1.93k
252	1.93k	if (asprintf(&source_time, "_SOURCE_MONOTONIC_TIMESTAMP=%llu", usec) >= 0)
253	1.93k	iovec[n++] = IOVEC_MAKE_STRING(source_time);
254	1.93k
255	1.93k	iovec[n++] = IOVEC_MAKE_STRING("_TRANSPORT=kernel");
256	1.93k
257	1.93k	if (asprintf(&syslog_priority, "PRIORITY=%i", priority & LOG_PRIMASK) >= 0)
258	1.93k	iovec[n++] = IOVEC_MAKE_STRING(syslog_priority);
259	1.93k
260	1.93k	if (asprintf(&syslog_facility, "SYSLOG_FACILITY=%i", LOG_FAC(priority)) >= 0)
261	1.93k	iovec[n++] = IOVEC_MAKE_STRING(syslog_facility);
262	1.93k
263	1.93k	if (LOG_FAC(priority) == LOG_KERN)
264	1.93k	iovec[n++] = IOVEC_MAKE_STRING("SYSLOG_IDENTIFIER=kernel");
265	1.93k	else {
266	467	pl -= syslog_parse_identifier((const char**) &p, &identifier, &pid);
267	467
268	467	/* Avoid any messages we generated ourselves via
269	467	* log_info() and friends. */
270	467	if (is_us(identifier, pid))
271	0	goto finish;
272	467
273	467	if (identifier) {
274	270	syslog_identifier = strappend("SYSLOG_IDENTIFIER=", identifier);
275	270	if (syslog_identifier)
276	270	iovec[n++] = IOVEC_MAKE_STRING(syslog_identifier);
277	270	}
278	467
279	467	if (pid) {
280	202	syslog_pid = strappend("SYSLOG_PID=", pid);
281	202	if (syslog_pid)
282	202	iovec[n++] = IOVEC_MAKE_STRING(syslog_pid);
283	202	}
284	467	}
285	1.93k
286	1.93k	if (cunescape_length_with_prefix(p, pl, "MESSAGE=", UNESCAPE_RELAX, &message) >= 0)
287	1.93k	iovec[n++] = IOVEC_MAKE_STRING(message);
288	1.93k
289	1.93k	server_dispatch_message(s, iovec, n, ELEMENTSOF(iovec), NULL, NULL, priority, 0);
290	1.93k
291	1.94k	finish:
292	3.93k	for (j = 0; j < z; j++)
293	1.99k	free(iovec[j].iov_base);
294	1.94k	}
295
296	0	static int server_read_dev_kmsg(Server *s) {
297	0	char buffer[8192+1]; /* the kernel-side limit per record is 8K currently */
298	0	ssize_t l;
299	0
300	0	assert(s);
301	0	assert(s->dev_kmsg_fd >= 0);
302	0
303	0	l = read(s->dev_kmsg_fd, buffer, sizeof(buffer) - 1);
304	0	if (l == 0)
305	0	return 0;
306	0	if (l < 0) {
307	0	/* Old kernels who don't allow reading from /dev/kmsg
308	0	* return EINVAL when we try. So handle this cleanly,
309	0	* but don' try to ever read from it again. */
310	0	if (errno == EINVAL) {
311	0	s->dev_kmsg_event_source = sd_event_source_unref(s->dev_kmsg_event_source);
312	0	return 0;
313	0	}
314	0
315	0	if (IN_SET(errno, EAGAIN, EINTR, EPIPE))
316	0	return 0;
317	0
318	0	return log_error_errno(errno, "Failed to read from kernel: %m");
319	0	}
320	0
321	0	dev_kmsg_record(s, buffer, l);
322	0	return 1;
323	0	}
324
325	0	int server_flush_dev_kmsg(Server *s) {
326	0	int r;
327	0
328	0	assert(s);
329	0
330	0	if (s->dev_kmsg_fd < 0)
331	0	return 0;
332	0
333	0	if (!s->dev_kmsg_readable)
334	0	return 0;
335	0
336	0	log_debug("Flushing /dev/kmsg...");
337	0
338	0	for (;;) {
339	0	r = server_read_dev_kmsg(s);
340	0	if (r < 0)
341	0	return r;
342	0
343	0	if (r == 0)
344	0	break;
345	0	}
346	0
347	0	return 0;
348	0	}
349
350	0	static int dispatch_dev_kmsg(sd_event_source es, int fd, uint32_t revents, void userdata) {
351	0	Server *s = userdata;
352	0
353	0	assert(es);
354	0	assert(fd == s->dev_kmsg_fd);
355	0	assert(s);
356	0
357	0	if (revents & EPOLLERR)
358	0	log_warning("/dev/kmsg buffer overrun, some messages lost.");
359	0
360	0	if (!(revents & EPOLLIN))
361	0	log_error("Got invalid event from epoll for /dev/kmsg: %"PRIx32, revents);
362	0
363	0	return server_read_dev_kmsg(s);
364	0	}
365
366	0	int server_open_dev_kmsg(Server *s) {
367	0	mode_t mode;
368	0	int r;
369	0
370	0	assert(s);
371	0
372	0	if (s->read_kmsg)
373	0	mode = O_RDWR\|O_CLOEXEC\|O_NONBLOCK\|O_NOCTTY;
374	0	else
375	0	mode = O_WRONLY\|O_CLOEXEC\|O_NONBLOCK\|O_NOCTTY;
376	0
377	0	s->dev_kmsg_fd = open("/dev/kmsg", mode);
378	0	if (s->dev_kmsg_fd < 0) {
379	0	log_full(errno == ENOENT ? LOG_DEBUG : LOG_WARNING,
380	0	"Failed to open /dev/kmsg, ignoring: %m");
381	0	return 0;
382	0	}
383	0
384	0	if (!s->read_kmsg)
385	0	return 0;
386	0
387	0	r = sd_event_add_io(s->event, &s->dev_kmsg_event_source, s->dev_kmsg_fd, EPOLLIN, dispatch_dev_kmsg, s);
388	0	if (r < 0) {
389	0
390	0	/* This will fail with EPERM on older kernels where
391	0	* /dev/kmsg is not readable. */
392	0	if (r == -EPERM) {
393	0	r = 0;
394	0	goto fail;
395	0	}
396	0
397	0	log_error_errno(r, "Failed to add /dev/kmsg fd to event loop: %m");
398	0	goto fail;
399	0	}
400	0
401	0	r = sd_event_source_set_priority(s->dev_kmsg_event_source, SD_EVENT_PRIORITY_IMPORTANT+10);
402	0	if (r < 0) {
403	0	log_error_errno(r, "Failed to adjust priority of kmsg event source: %m");
404	0	goto fail;
405	0	}
406	0
407	0	s->dev_kmsg_readable = true;
408	0
409	0	return 0;
410	0
411	0	fail:
412	0	s->dev_kmsg_event_source = sd_event_source_unref(s->dev_kmsg_event_source);
413	0	s->dev_kmsg_fd = safe_close(s->dev_kmsg_fd);
414	0
415	0	return r;
416	0	}
417
418	0	int server_open_kernel_seqnum(Server *s) {
419	0	_cleanup_close_ int fd;
420	0	uint64_t *p;
421	0	int r;
422	0
423	0	assert(s);
424	0
425	0	/* We store the seqnum we last read in an mmaped file. That
426	0	* way we can just use it like a variable, but it is
427	0	* persistent and automatically flushed at reboot. */
428	0
429	0	fd = open("/run/systemd/journal/kernel-seqnum", O_RDWR\|O_CREAT\|O_CLOEXEC\|O_NOCTTY\|O_NOFOLLOW, 0644);
430	0	if (fd < 0) {
431	0	log_error_errno(errno, "Failed to open /run/systemd/journal/kernel-seqnum, ignoring: %m");
432	0	return 0;
433	0	}
434	0
435	0	r = posix_fallocate(fd, 0, sizeof(uint64_t));
436	0	if (r != 0) {
437	0	log_error_errno(r, "Failed to allocate sequential number file, ignoring: %m");
438	0	return 0;
439	0	}
440	0
441	0	p = mmap(NULL, sizeof(uint64_t), PROT_READ\|PROT_WRITE, MAP_SHARED, fd, 0);
442	0	if (p == MAP_FAILED) {
443	0	log_error_errno(errno, "Failed to map sequential number file, ignoring: %m");
444	0	return 0;
445	0	}
446	0
447	0	s->kernel_seqnum = p;
448	0
449	0	return 0;
450	0	}