chan_pjsip: Make logger togglable without loading/unloading

This patch makes the res_pjsip_logger do a few things... First, it
will be built and installed by default now, so end users won't need
to enable it in menuselect. Second, while it is loaded, it no longer
will immediately issue log messages. Upon loading, it is in the
disabled state and must be turned on with the new CLI command. The
CLI command 'pjsip set logger <on/off/host> has been added and can be
used to do the following:
pjsip set logger on:
    Enables logger for all PJSIP traffic
pjsip set logger off:
    Disables logger for all PJSIP traffic
pjsip set logger host <host>:
    Enables logger for the specific host

Review: https://reviewboard.asterisk.org/r/2900/
........

Merged revisions 400542 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@400543 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_pjsip_logger.c

@@ -19,7 +19,7 @@
 /*** MODULEINFO
 	<depend>pjproject</depend>
 	<depend>res_pjsip</depend>
-	<defaultenabled>no</defaultenabled>
+	<defaultenabled>yes</defaultenabled>
 	<support_level>core</support_level>
  ***/
 
@@ -30,9 +30,79 @@
 #include "asterisk/res_pjsip.h"
 #include "asterisk/module.h"
 #include "asterisk/logger.h"
+#include "asterisk/cli.h"
+#include "asterisk/netsock2.h"
+
+enum pjsip_logging_mode {
+	LOGGING_MODE_DISABLED,    /* No logging is enabled */
+	LOGGING_MODE_ENABLED,     /* Logging is enabled */
+};
+
+static enum pjsip_logging_mode logging_mode;
+static struct ast_sockaddr log_addr;
+
+/*! \brief  Return the first entry from ast_sockaddr_resolve filtered by address family
+ *
+ * \warning Using this function probably means you have a faulty design.
+ * \note This function was taken from the function of the same name in chan_sip.c
+ */
+static int ast_sockaddr_resolve_first_af(struct ast_sockaddr *addr,
+				      const char* name, int flag, int family)
+{
+	struct ast_sockaddr *addrs;
+	int addrs_cnt;
+
+	addrs_cnt = ast_sockaddr_resolve(&addrs, name, flag, family);
+	if (addrs_cnt <= 0) {
+		return 1;
+	}
+	if (addrs_cnt > 1) {
+		ast_debug(1, "Multiple addresses, using the first one only\n");
+	}
+
+	ast_sockaddr_copy(addr, &addrs[0]);
+
+	ast_free(addrs);
+	return 0;
+}
+
+/*! \brief See if we pass debug IP filter */
+static inline int pjsip_log_test_addr(const char *address, int port)
+{
+	struct ast_sockaddr test_addr;
+	if (logging_mode == LOGGING_MODE_DISABLED) {
+		return 0;
+	}
+
+	/* A null logging address means we'll debug any address */
+	if (ast_sockaddr_isnull(&log_addr)) {
+		return 1;
+	}
+
+	/* A null address was passed in. Just reject it. */
+	if (ast_strlen_zero(address)) {
+		return 0;
+	}
+
+	ast_sockaddr_parse(&test_addr, address, PARSE_PORT_IGNORE);
+	ast_sockaddr_set_port(&test_addr, port);
+
+	/* If no port was specified for a debug address, just compare the
+	 * addresses, otherwise compare the address and port
+	 */
+	if (ast_sockaddr_port(&log_addr)) {
+		return !ast_sockaddr_cmp(&log_addr, &test_addr);
+	} else {
+		return !ast_sockaddr_cmp_addr(&log_addr, &test_addr);
+	}
+}
 
 static pj_status_t logging_on_tx_msg(pjsip_tx_data *tdata)
 {
+	if (!pjsip_log_test_addr(tdata->tp_info.dst_name, tdata->tp_info.dst_port)) {
+		return PJ_SUCCESS;
+	}
+
 	ast_verbose("<--- Transmitting SIP %s (%d bytes) to %s:%s:%d --->\n%.*s\n",
 		    tdata->msg->type == PJSIP_REQUEST_MSG ? "request" : "response",
 		    (int) (tdata->buf.cur - tdata->buf.start),
@@ -45,6 +115,10 @@ static pj_status_t logging_on_tx_msg(pjsip_tx_data *tdata)
 
 static pj_bool_t logging_on_rx_msg(pjsip_rx_data *rdata)
 {
+	if (!pjsip_log_test_addr(rdata->pkt_info.src_name, rdata->pkt_info.src_port)) {
+		return PJ_FALSE;
+	}
+
 	ast_verbose("<--- Received SIP %s (%d bytes) from %s:%s:%d --->\n%s\n",
 		    rdata->msg_info.msg->type == PJSIP_REQUEST_MSG ? "request" : "response",
 		    rdata->msg_info.len,
@@ -64,14 +138,71 @@ static pjsip_module logging_module = {
 	.on_tx_response = logging_on_tx_msg,
 };
 
+static char *pjsip_enable_logger_host(int fd, const char *arg)
+{
+	if (ast_sockaddr_resolve_first_af(&log_addr, arg, 0, AST_AF_UNSPEC)) {
+		return CLI_SHOWUSAGE;
+	}
+
+	ast_cli(fd, "PJSIP Logging Enabled for host: %s\n", ast_sockaddr_stringify_addr(&log_addr));
+	logging_mode = LOGGING_MODE_ENABLED;
+
+	return CLI_SUCCESS;
+}
+
+static char *pjsip_set_logger(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
+{
+	const char *what;
+
+	if (cmd == CLI_INIT) {
+		e->command = "pjsip set logger {on|off|host}";
+		e->usage =
+			"Usage: pjsip set logger {on|off}\n"
+			"       Enables or disabling logging of SIP packets\n"
+			"       read on ports bound to PJSIP transports either\n"
+			"       globally or enables logging for an individual\n"
+			"       host.\n";
+		return NULL;
+	} else if (cmd == CLI_GENERATE) {
+		return NULL;
+	}
+
+	what = a->argv[e->args - 1];     /* Guaranteed to exist */
+
+	if (a->argc == e->args) {        /* on/off */
+		if (!strcasecmp(what, "on")) {
+			logging_mode = LOGGING_MODE_ENABLED;
+			ast_cli(a->fd, "PJSIP Logging enabled\n");
+			ast_sockaddr_setnull(&log_addr);
+			return CLI_SUCCESS;
+		} else if (!strcasecmp(what, "off")) {
+			logging_mode = LOGGING_MODE_DISABLED;
+			ast_cli(a->fd, "PJSIP Logging disabled\n");
+			return CLI_SUCCESS;
+		}
+	} else if (a->argc == e->args + 1) {
+		if (!strcasecmp(what, "host")) {
+			return pjsip_enable_logger_host(a->fd, a->argv[e->args]);
+		}
+	}
+
+	return CLI_SHOWUSAGE;
+}
+
+static struct ast_cli_entry cli_pjsip[] = {
+	AST_CLI_DEFINE(pjsip_set_logger, "Enable/Disable PJSIP Logger Output")
+};
+
 static int load_module(void)
 {
 	ast_sip_register_service(&logging_module);
+	ast_cli_register_multiple(cli_pjsip, ARRAY_LEN(cli_pjsip));
 	return AST_MODULE_LOAD_SUCCESS;
 }
 
 static int unload_module(void)
 {
+	ast_cli_unregister_multiple(cli_pjsip, ARRAY_LEN(cli_pjsip));
 	ast_sip_unregister_service(&logging_module);
 	return 0;
 }