Implement GSMTAP log target

This target wraps the to-be-logged string (With metadata) into a GSMTAP
packet and sends it to the configured destination address.

Change-Id: I9a7e72b8c9c6f6f2d76d1ea2332dcdee12394625

6 files changed, 184 insertions, 3 deletions

diff --git a/TODO-RELEASE b/TODO-RELEASE
index 648b6a6d..17f6521d 100644
--- a/TODO-RELEASE
+++ b/TODO-RELEASE
@@ -4,3 +4,4 @@ libosmocore	change major	external talloc dependency / internal talloc removal
 libosmocore	change major	size of ph_data_param struct changed / Extend L1SAP PH-DATA with presence information
 libosmocore	change major	size of ph_data_param struct changed / Extend L1SAP PH-DATA with measurement information
 libosmocore	change major	size of ph_tch_param struct changed / Extend with RTP Marker
+libosmocore	change major	size of struct log_target changed / Extend with GSMTAP
diff --git a/include/osmocom/core/logging.h b/include/osmocom/core/logging.h
index 581ebcec..ad775b9b 100644
--- a/include/osmocom/core/logging.h
+++ b/include/osmocom/core/logging.h
@@ -9,6 +9,7 @@
 #include <stdio.h>
 #include <stdint.h>
 #include <stdarg.h>
+#include <stdbool.h>
 #include <osmocom/core/linuxlist.h>
 
 /*! \brief Maximum number of logging contexts */
@@ -122,6 +123,7 @@ typedef int log_filter(const struct log_context *ctx,
 
 struct log_info;
 struct vty;
+struct gsmtap_inst;
 
 typedef void log_print_filters(struct vty *vty,
 			       const struct log_info *info,
@@ -156,6 +158,7 @@ enum log_target_type {
 	LOG_TGT_TYPE_FILE,	/*!< \brief text file logging */
 	LOG_TGT_TYPE_STDERR,	/*!< \brief stderr logging */
 	LOG_TGT_TYPE_STRRB,	/*!< \brief osmo_strrb-backed logging */
+	LOG_TGT_TYPE_GSMTAP,	/*!< \brief GSMTAP network logging */
 };
 
 /*! \brief structure representing a logging target */
@@ -204,6 +207,12 @@ struct log_target {
 		struct {
 			void *rb;
 		} tgt_rb;
+
+		struct {
+			struct gsmtap_inst *gsmtap_inst;
+			const char *ident;
+			const char *hostname;
+		} tgt_gsmtap;
 	};
 
 	/*! \brief call-back function to be called when the logging framework
@@ -254,6 +263,7 @@ void log_set_print_filename(struct log_target *target, int);
 void log_set_print_category(struct log_target *target, int);
 void log_set_log_level(struct log_target *target, int log_level);
 void log_parse_category_mask(struct log_target *target, const char* mask);
+const char* log_category_name(int subsys);
 int log_parse_level(const char *lvl);
 const char *log_level_str(unsigned int lvl);
 int log_parse_category(const char *category);
@@ -267,6 +277,10 @@ struct log_target *log_target_create_stderr(void);
 struct log_target *log_target_create_file(const char *fname);
 struct log_target *log_target_create_syslog(const char *ident, int option,
 					    int facility);
+struct log_target *log_target_create_gsmtap(const char *host, uint16_t port,
+					    const char *ident,
+					    bool ofd_wq_mode,
+					    bool add_sink);
 int log_target_file_reopen(struct log_target *tgt);
 int log_targets_reopen(void);
 
diff --git a/src/Makefile.am b/src/Makefile.am
index 74bdb213..6a9c6758 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -11,7 +11,7 @@ libosmocore_la_LIBADD = $(BACKTRACE_LIB) $(TALLOC_LIBS)
 libosmocore_la_SOURCES = timer.c timer_gettimeofday.c select.c signal.c msgb.c bits.c \
 			 bitvec.c bitcomp.c statistics.c fsm.c \
 			 write_queue.c utils.c socket.c \
-			 logging.c logging_syslog.c rate_ctr.c \
+			 logging.c logging_syslog.c logging_gsmtap.c rate_ctr.c \
 			 gsmtap_util.c crc16.c panic.c backtrace.c \
 			 conv.c application.c rbtree.c strrb.c \
 			 loggingrb.c crc8gen.c crc16gen.c crc32gen.c crc64gen.c \
diff --git a/src/logging.c b/src/logging.c
index 165d8229..1516a7d8 100644
--- a/src/logging.c
+++ b/src/logging.c
@@ -240,7 +240,7 @@ static const char* color(int subsys)
 	return NULL;
 }
 
-static const char* category_name(int subsys)
+const char* log_category_name(int subsys)
 {
 	if (subsys < osmo_log_info->num_cat)
 		return osmo_log_info->cat[subsys].name;
@@ -290,7 +290,7 @@ static void _output(struct log_target *target, unsigned int subsys,
 			OSMO_SNPRINTF_RET(ret, rem, offset, len);
 		}
 		if (target->print_category) {
-			ret = snprintf(buf + offset, rem, "%s ", category_name(subsys));
+			ret = snprintf(buf + offset, rem, "%s ", log_category_name(subsys));
 			if (ret < 0)
 				goto err;
 			OSMO_SNPRINTF_RET(ret, rem, offset, len);
diff --git a/src/logging_gsmtap.c b/src/logging_gsmtap.c
new file mode 100644
index 00000000..85f8c28b
--- /dev/null
+++ b/src/logging_gsmtap.c
@@ -0,0 +1,134 @@
+/* GSMTAP network logging support code */
+
+/* (C) 2016 by Harald Welte <laforge@gnumonks.org>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+/*! \addtogroup logging
+ *  @{
+ */
+
+/*! \file logging_gsmtap.c */
+
+#include "../config.h"
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include <arpa/inet.h>
+
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/gsmtap.h>
+#include <osmocom/core/gsmtap_util.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/timer.h>
+
+#define	GSMTAP_LOG_MAX_SIZE 4096
+
+static void _gsmtap_raw_output(struct log_target *target, int subsys,
+			       unsigned int level, const char *file,
+			       int line, int cont, const char *format,
+			       va_list ap)
+{
+	struct msgb *msg;
+	struct gsmtap_hdr *gh;
+	struct gsmtap_osmocore_log_hdr *golh;
+	const char *subsys_name = log_category_name(subsys);
+	struct timeval tv;
+	int rc;
+
+	/* get timestamp ASAP */
+	osmo_gettimeofday(&tv, NULL);
+
+	msg = msgb_alloc(sizeof(*gh)+sizeof(*golh)+GSMTAP_LOG_MAX_SIZE,
+			 "GSMTAP logging");
+
+	/* GSMTAP header */
+	gh = (struct gsmtap_hdr *) msgb_put(msg, sizeof(*gh));
+	memset(gh, 0, sizeof(*gh));
+	gh->version = GSMTAP_VERSION;
+	gh->hdr_len = sizeof(*gh)/4;
+	gh->type = GSMTAP_TYPE_OSMOCORE_LOG;
+
+	/* Logging header */
+	golh = (struct gsmtap_osmocore_log_hdr *) msgb_put(msg, sizeof(*golh));
+	osmo_strlcpy(golh->proc_name, target->tgt_gsmtap.ident,
+		     sizeof(golh->proc_name));
+	if (subsys_name)
+		osmo_strlcpy(golh->subsys, subsys_name+1, sizeof(golh->subsys));
+	else
+		golh->subsys[0] = '\0';
+	osmo_strlcpy(golh->src_file.name, file, sizeof(golh->src_file.name));
+	golh->src_file.line_nr = htonl(line);
+	golh->level = level;
+	/* we always store the timestamp in the message, irrespective
+	 * of hat prrint_[ext_]timestamp say */
+	golh->ts.sec = htonl(tv.tv_sec);
+	golh->ts.usec = htonl(tv.tv_usec);
+
+	rc = vsnprintf((char *) msg->tail, msgb_tailroom(msg), format, ap);
+	if (rc < 0)
+		return;
+	msgb_put(msg, rc);
+
+	gsmtap_sendmsg(target->tgt_gsmtap.gsmtap_inst, msg);
+}
+
+/*! \brief Create a new logging target for GSMTAP logging
+ *  \param[in] ident string identifier
+ *  \returns Log target in case of success, NULL in case of error
+ */
+struct log_target *log_target_create_gsmtap(const char *host, uint16_t port,
+					    const char *ident,
+					    bool ofd_wq_mode,
+					    bool add_sink)
+{
+	struct log_target *target;
+	struct gsmtap_inst *gti;
+
+	target = log_target_create();
+	if (!target)
+		return NULL;
+
+	gti = gsmtap_source_init(host, port, ofd_wq_mode);
+	if (!gti) {
+		log_target_destroy(target);
+		return NULL;
+	}
+
+	if (add_sink)
+		gsmtap_source_add_sink(gti);
+
+	target->tgt_gsmtap.gsmtap_inst = gti;
+	target->tgt_gsmtap.ident = talloc_strdup(target, ident);
+	target->tgt_gsmtap.hostname = talloc_strdup(target, host);
+
+	target->type = LOG_TGT_TYPE_GSMTAP;
+	target->raw_output = _gsmtap_raw_output;
+
+	return target;
+}
+
+/* @} */
diff --git a/src/vty/logging_vty.c b/src/vty/logging_vty.c
index d2fca819..cf3ec219 100644
--- a/src/vty/logging_vty.c
+++ b/src/vty/logging_vty.c
@@ -29,6 +29,7 @@
 #include <osmocom/core/utils.h>
 #include <osmocom/core/strrb.h>
 #include <osmocom/core/loggingrb.h>
+#include <osmocom/core/gsmtap.h>
 
 #include <osmocom/vty/command.h>
 #include <osmocom/vty/buffer.h>
@@ -498,6 +499,32 @@ DEFUN(cfg_no_log_syslog, cfg_no_log_syslog_cmd,
 }
 #endif /* HAVE_SYSLOG_H */
 
+DEFUN(cfg_log_gsmtap, cfg_log_gsmtap_cmd,
+	"log gsmtap [HOSTNAME]",
+	LOG_STR "Logging via GSMTAP\n")
+{
+	const char *hostname = argv[0];
+	struct log_target *tgt;
+
+	tgt = log_target_find(LOG_TGT_TYPE_GSMTAP, hostname);
+	if (!tgt) {
+		tgt = log_target_create_gsmtap(hostname, GSMTAP_UDP_PORT,
+					       host.app_info->name, false,
+					       true);
+		if (!tgt) {
+			vty_out(vty, "%% Unable to create GSMTAP log%s",
+				VTY_NEWLINE);
+			return CMD_WARNING;
+		}
+		log_add_target(tgt);
+	}
+
+	vty->index = tgt;
+	vty->node = CFG_LOG_NODE;
+
+	return CMD_SUCCESS;
+}
+
 DEFUN(cfg_log_stderr, cfg_log_stderr_cmd,
 	"log stderr",
 	LOG_STR "Logging via STDERR of the process\n")
@@ -652,6 +679,10 @@ static int config_write_log_single(struct vty *vty, struct log_target *tgt)
 		vty_out(vty, "log alarms %zu%s",
 			log_target_rb_avail_size(tgt), VTY_NEWLINE);
 		break;
+	case LOG_TGT_TYPE_GSMTAP:
+		vty_out(vty, "log gsmtap %s%s",
+			tgt->tgt_gsmtap.hostname, VTY_NEWLINE);
+		break;
 	}
 
 	vty_out(vty, "  logging filter all %u%s",
@@ -744,4 +775,5 @@ void logging_vty_add_cmds(const struct log_info *cat)
 	install_element(CONFIG_NODE, &cfg_log_syslog_local_cmd);
 	install_element(CONFIG_NODE, &cfg_no_log_syslog_cmd);
 #endif
+	install_element(CONFIG_NODE, &cfg_log_gsmtap_cmd);
 }