[OpenWrt-Devel] [PATCH] instance: add support for customizable syslog facilities

[Michael Heimpold]

This allow using a different (read: user-defined) syslog facility
other than LOG_DAEMON when an instance's stdout/stderr is forwarded
to syslog.
It might be used to handle such messages different, e.g.
filter/forward them etc.

Signed-off-by: Michael Heimpold <mhei at heimpold.de>
---
 service/instance.c | 34 +++++++++++++++++++++++++++++++++-
 service/instance.h |  1 +
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/service/instance.c b/service/instance.c
index 3b92536..983494b 100644
--- a/service/instance.c
+++ b/service/instance.c
@@ -26,6 +26,8 @@
 #include <pwd.h>
 #include <libgen.h>
 #include <unistd.h>
+#define SYSLOG_NAMES
+#include <syslog.h>
 
 #include <libubox/md5.h>
 
@@ -58,6 +60,7 @@ enum {
 	INSTANCE_ATTR_PIDFILE,
 	INSTANCE_ATTR_RELOADSIG,
 	INSTANCE_ATTR_TERMTIMEOUT,
+	INSTANCE_ATTR_FACILITY,
 	__INSTANCE_ATTR_MAX
 };
 
@@ -84,6 +87,7 @@ static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
 	[INSTANCE_ATTR_PIDFILE] = { "pidfile", BLOBMSG_TYPE_STRING },
 	[INSTANCE_ATTR_RELOADSIG] = { "reload_signal", BLOBMSG_TYPE_INT32 },
 	[INSTANCE_ATTR_TERMTIMEOUT] = { "term_timeout", BLOBMSG_TYPE_INT32 },
+	[INSTANCE_ATTR_FACILITY] = { "facility", BLOBMSG_TYPE_STRING },
 };
 
 enum {
@@ -150,6 +154,18 @@ static void closefd(int fd)
 		close(fd);
 }
 
+/* convert a string into numeric syslog facility or return -1 if no match found */
+static int
+syslog_facility_str_to_int(const char *facility)
+{
+	CODE *p = facilitynames;
+
+	while (p->c_name && strcasecmp(p->c_name, facility))
+		p++;
+
+	return p->c_val;
+}
+
 static void
 instance_limits(const char *limit, const char *value)
 {
@@ -468,7 +484,7 @@ instance_stdio(struct ustream *s, int prio, struct service_instance *in)
 
 	arg0 = basename(blobmsg_data(blobmsg_data(in->command)));
 	snprintf(ident, sizeof(ident), "%s[%d]", arg0, in->proc.pid);
-	ulog_open(ULOG_SYSLOG, LOG_DAEMON, ident);
+	ulog_open(ULOG_SYSLOG, in->syslog_facility, ident);
 
 	do {
 		str = ustream_get_read_buf(s, &len);
@@ -622,6 +638,9 @@ instance_config_changed(struct service_instance *in, struct service_instance *in
 	if (in->nice != in_new->nice)
 		return true;
 
+	if (in->syslog_facility != in_new->syslog_facility)
+		return true;
+
 	if (string_changed(in->user, in_new->user))
 		return true;
 
@@ -944,6 +963,17 @@ instance_config_parse(struct service_instance *in)
 	if (!instance_fill_array(&in->errors, tb[INSTANCE_ATTR_ERROR], NULL, true))
 		return false;
 
+	if (tb[INSTANCE_ATTR_FACILITY]) {
+		int facility = syslog_facility_str_to_int(blobmsg_get_string(tb[INSTANCE_ATTR_FACILITY]));
+		if (facility != -1) {
+			DEBUG(3, "setting facility '%s'\n", blobmsg_get_string(tb[INSTANCE_ATTR_FACILITY]));
+			in->syslog_facility = facility;
+		} else {
+			DEBUG(3, "unknown syslog facility '%s' given, using default (LOG_DAEMON)\n", blobmsg_get_string(tb[INSTANCE_ATTR_FACILITY]));
+			in->syslog_facility = LOG_DAEMON;
+		}
+	}
+
 	return true;
 }
 
@@ -980,6 +1010,7 @@ instance_config_move(struct service_instance *in, struct service_instance *in_sr
 	in->trace = in_src->trace;
 	in->seccomp = in_src->seccomp;
 	in->node.avl.key = in_src->node.avl.key;
+	in->syslog_facility = in_src->syslog_facility;
 
 	free(in->config);
 	in->config = in_src->config;
@@ -1029,6 +1060,7 @@ instance_init(struct service_instance *in, struct service *s, struct blob_attr *
 	in->timeout.cb = instance_timeout;
 	in->proc.cb = instance_exit;
 	in->term_timeout = 5;
+	in->syslog_facility = LOG_DAEMON;
 
 	in->_stdout.fd.fd = -2;
 	in->_stdout.stream.string_data = true;
diff --git a/service/instance.h b/service/instance.h
index 84ce002..42cc4be 100644
--- a/service/instance.h
+++ b/service/instance.h
@@ -61,6 +61,7 @@ struct service_instance {
 	struct jail jail;
 	char *seccomp;
 	char *pidfile;
+	int syslog_facility;
 
 	uint32_t term_timeout;
 	uint32_t respawn_timeout;
-- 
2.17.1


_______________________________________________
openwrt-devel mailing list
openwrt-devel at lists.openwrt.org
https://lists.openwrt.org/mailman/listinfo/openwrt-devel