Adding upstream version 8.2402.0.upstream/8.2402.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 327 insertions, 0 deletions

diff --git a/contrib/imkmsg/kmsg.c b/contrib/imkmsg/kmsg.c
new file mode 100644
index 0000000..2548634
--- /dev/null
+++ b/contrib/imkmsg/kmsg.c
@@ -0,0 +1,327 @@
+/* imkmsg driver for Linux /dev/kmsg structured logging
+ *
+ * This contains Linux-specific functionality to read /dev/kmsg
+ * For a general overview, see head comment in imkmsg.c.
+ * This is heavily based on imklog bsd.c file.
+ *
+ * Copyright 2008-2023 Adiscon GmbH
+ *
+ * This file is part of rsyslog.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *       -or-
+ *       see COPYING.ASL20 in the source distribution
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifdef HAVE_CONFIG_H
+#	include "config.h"
+#endif
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <ctype.h>
+#include <sys/klog.h>
+#include <sys/sysinfo.h>
+#include <sys/time.h>
+#include <json.h>
+
+#include "rsyslog.h"
+#include "srUtils.h"
+#include "debug.h"
+#include "imkmsg.h"
+
+/* globals */
+static int	fklog = -1;	/* kernel log fd */
+static int	bInInitialReading = 1; /* are we in the intial kmsg reading phase? */
+/* Note: There is a problem with kernel log time.
+ * See https://github.com/troglobit/sysklogd/commit/9f6fbb3301e571d8af95f8d771469291384e9e95
+ * We use the same work-around if bFixKernelStamp is on, and use the kernel log time
+ * only for past records, which we assume to be from recent boot. Later on, we do not
+ * use them but system time.
+ * UNFORTUNATELY, with /dev/kmsg, we always get old messages on startup. That means we
+ * may also pull old messages. We do not address this right now, as for 10 years "old
+ * messages" was pretty acceptable. So we wait until someone complains. Hint: we could
+ * do a seek to the end of kmsg if desired to not pull old messages.
+ * 2023-10-31 rgerhards
+ */
+
+#ifndef _PATH_KLOG
+#	define _PATH_KLOG "/dev/kmsg"
+#endif
+
+/* submit a message to imkmsg Syslog() API. In this function, we parse
+ * necessary information from kernel log line, and make json string
+ * from the rest.
+ */
+static void
+submitSyslog(modConfData_t *const pModConf, const uchar *buf)
+{
+	long offs = 0;
+	struct timeval tv;
+	struct timeval *tp = NULL;
+	struct sysinfo info;
+	unsigned long int timestamp = 0;
+	char name[1024];
+	char value[1024];
+	char msg[1024];
+	syslog_pri_t priority = 0;
+	long int sequnum = 0;
+	struct json_object *json = NULL, *jval;
+
+	/* create new json object */
+	json = json_object_new_object();
+
+	/* get priority */
+	for (; isdigit(*buf); buf++) {
+		priority = (priority * 10) + (*buf - '0');
+	}
+	buf++;
+
+	/* get messages sequence number and add it to json */
+	for (; isdigit(*buf); buf++) {
+		sequnum = (sequnum * 10) + (*buf - '0');
+	}
+	buf++; /* skip , */
+	jval = json_object_new_int(sequnum);
+	json_object_object_add(json, "sequnum", jval);
+
+	/* get timestamp */
+	for (; isdigit(*buf); buf++) {
+		timestamp = (timestamp * 10) + (*buf - '0');
+	}
+
+	while (*buf != ';') {
+		buf++; /* skip everything till the first ; */
+	}
+	buf++; /* skip ; */
+
+	/* get message */
+	offs = 0;
+	for (; *buf != '\n' && *buf != '\0'; buf++, offs++) {
+		msg[offs] = *buf;
+	}
+	msg[offs] = '\0';
+	jval = json_object_new_string((char*)msg);
+	json_object_object_add(json, "msg", jval);
+
+	if (*buf != '\0') /* message has appended properties, skip \n */
+		buf++;
+
+	while (*buf) {
+		/* get name of the property */
+		buf++; /* skip ' ' */
+		offs = 0;
+		for (; *buf != '=' && *buf != ' '; buf++, offs++) {
+			name[offs] = *buf;
+		}
+		name[offs] = '\0';
+		buf++; /* skip = or ' ' */;
+
+		offs = 0;
+		for (; *buf != '\n' && *buf != '\0'; buf++, offs++) {
+			value[offs] = *buf;
+		}
+		value[offs] = '\0';
+		if (*buf != '\0') {
+			buf++; /* another property, skip \n */
+		}
+
+		jval = json_object_new_string((char*)value);
+		json_object_object_add(json, name, jval);
+	}
+
+	if(   (pModConf->parseKernelStamp == KMSG_PARSE_TS_ALWAYS)
+	   || ((pModConf->parseKernelStamp == KMSG_PARSE_TS_STARTUP_ONLY) && bInInitialReading) ) {
+		/* calculate timestamp */
+		sysinfo(&info);
+		gettimeofday(&tv, NULL);
+
+		/* get boot time */
+		tv.tv_sec -= info.uptime;
+
+		tv.tv_sec += timestamp / 1000000;
+		tv.tv_usec += timestamp % 1000000;
+
+		while (tv.tv_usec < 0) {
+			tv.tv_sec--;
+			tv.tv_usec += 1000000;
+		}
+
+		while (tv.tv_usec >= 1000000) {
+			tv.tv_sec++;
+			tv.tv_usec -= 1000000;
+		}
+
+		tp = &tv;
+	}
+
+	Syslog(priority, (uchar *)msg, tp, json);
+}
+
+
+/* open the kernel log - will be called inside the willRun() imkmsg entry point
+ */
+rsRetVal
+klogWillRunPrePrivDrop(modConfData_t __attribute__((unused)) *pModConf)
+{
+	char errmsg[2048];
+	DEFiRet;
+
+	fklog = open(_PATH_KLOG, O_RDONLY | O_NONBLOCK, 0);
+	if (fklog < 0) {
+		imkmsgLogIntMsg(LOG_ERR, "imkmsg: cannot open kernel log (%s): %s.",
+			_PATH_KLOG, rs_strerror_r(errno, errmsg, sizeof(errmsg)));
+		ABORT_FINALIZE(RS_RET_ERR_OPEN_KLOG);
+	}
+
+finalize_it:
+	RETiRet;
+}
+
+/* make sure the kernel log is readable after dropping privileges
+ */
+rsRetVal
+klogWillRunPostPrivDrop(modConfData_t __attribute__((unused)) *pModConf)
+{
+	char errmsg[2048];
+	int r;
+	DEFiRet;
+
+	/* this normally returns EINVAL */
+	/* on an OpenVZ VM, we get EPERM */
+	r = read(fklog, NULL, 0);
+	if (r < 0 && errno != EINVAL && errno != EAGAIN && errno != EWOULDBLOCK) {
+		imkmsgLogIntMsg(LOG_ERR, "imkmsg: cannot open kernel log (%s): %s.",
+			_PATH_KLOG, rs_strerror_r(errno, errmsg, sizeof(errmsg)));
+		fklog = -1;
+		ABORT_FINALIZE(RS_RET_ERR_OPEN_KLOG);
+	}
+
+finalize_it:
+	RETiRet;
+}
+
+
+static void
+change_reads_to_blocking(const int fd)
+{
+	const int flags = fcntl(fd, F_GETFL, 0);
+	fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
+}
+
+/* Read kernel log while data are available, each read() reads one
+ * record of printk buffer.
+ */
+static void
+readkmsg(modConfData_t *const pModConf)
+{
+	int i;
+	uchar pRcv[16*1024+1];
+	char errmsg[2048];
+	off_t seek_result = 0;
+
+	if(pModConf->readMode == KMSG_READMODE_FULL_BOOT) {
+		struct sysinfo info;
+		sysinfo(&info);
+		DBGPRINTF("imkmsg: system uptime is %lld, expected %d\n",
+			(long long) info.uptime, pModConf->expected_boot_complete_secs);
+		if(info.uptime > pModConf->expected_boot_complete_secs) {
+			seek_result = lseek(fklog, 0, SEEK_END);
+		}
+	} else if(pModConf->readMode == KMSG_READMODE_NEW_ONLY) {
+		seek_result = lseek(fklog, 0, SEEK_END);
+	} else if(pModConf->readMode != KMSG_READMODE_FULL_ALWAYS) {
+		imkmsgLogIntMsg(LOG_ERR, "imkmsg: internal program error, "
+				"unknown read mode %d, assuming 'full-always'",
+				pModConf->readMode);
+	}
+
+	if(seek_result == (off_t) -1) {
+		imkmsgLogIntMsg(LOG_WARNING,
+				"imkmsg: could not seek to requested klog entries - will"
+				"now potentially output all messages");
+	}
+
+	for (;;) {
+		dbgprintf("imkmsg waiting for kernel log line\n");
+
+		/* every read() from the opened device node receives one record of the printk buffer */
+		i = read(fklog, pRcv, 8192);
+		if (i > 0) {
+			/* successful read of message of nonzero length */
+			pRcv[i] = '\0';
+		} else if (i < 0 && errno == EPIPE) {
+			imkmsgLogIntMsg(LOG_WARNING,
+					"imkmsg: some messages in circular buffer got overwritten");
+			continue;
+		} else {
+			/* something went wrong - error or zero length message */
+			if(i < 0 && (errno == EAGAIN || errno == EWOULDBLOCK)) {
+				DBGPRINTF("imkmsg: initial read done, changing to blocking mode\n");
+				change_reads_to_blocking(fklog);
+				bInInitialReading = 0;
+				continue;
+			}
+			if(i < 0 && errno != EINTR && errno != EAGAIN) {
+				/* error occurred */
+				imkmsgLogIntMsg(LOG_ERR,
+				       "imkmsg: error reading kernel log - shutting down: %s",
+					rs_strerror_r(errno, errmsg, sizeof(errmsg)));
+				fklog = -1;
+			}
+			break;
+		}
+
+		submitSyslog(pModConf, pRcv);
+	}
+}
+
+
+/* to be called in the module's AfterRun entry point
+ * rgerhards, 2008-04-09
+ */
+rsRetVal klogAfterRun(modConfData_t *pModConf)
+{
+	DEFiRet;
+	if(fklog != -1)
+		close(fklog);
+	/* Turn on logging of messages to console, but only if a log level was speficied */
+	if(pModConf->console_log_level != -1)
+		klogctl(7, NULL, 0);
+	RETiRet;
+}
+
+
+/* to be called in the module's WillRun entry point, this is the main
+ * "message pull" mechanism.
+ * rgerhards, 2008-04-09
+ */
+rsRetVal klogLogKMsg(modConfData_t *const pModConf)
+{
+	DEFiRet;
+	readkmsg(pModConf);
+	RETiRet;
+}
+
+
+/* provide the (system-specific) default facility for internal messages
+ * rgerhards, 2008-04-14
+ */
+int
+klogFacilIntMsg(void)
+{
+	return LOG_SYSLOG;
+}
+