monitor: Add --noies option

To help understand scanning results a bit better and cut down on scan
output add an option to not print the contents of the IEs.  Only the
SSID IE will be printed.

monitor/main.c

@@ -671,6 +671,7 @@ static void usage(void)
 		"\t-n, --nortnl           Don't show RTNL output\n"
 		"\t-y, --nowiphy          Don't show 'New Wiphy' output\n"
 		"\t-s, --noscan           Don't show scan result output\n"
+		"\t-e, --noies            Don't show IEs except SSID\n"
 		"\t-h, --help             Show help options\n");
 }
 
@@ -683,6 +684,7 @@ static const struct option main_options[] = {
 	{ "nortnl",    no_argument,       NULL, 'n' },
 	{ "nowiphy",   no_argument,       NULL, 'y' },
 	{ "noscan",    no_argument,       NULL, 's' },
+	{ "noies",     no_argument,       NULL, 'e' },
 	{ "version",   no_argument,       NULL, 'v' },
 	{ "help",      no_argument,       NULL, 'h' },
 	{ }
@@ -746,6 +748,9 @@ int main(int argc, char *argv[])
 		case 's':
 			config.noscan = true;
 			break;
+		case 'e':
+			config.noies = true;
+			break;
 		case 'v':
 			printf("%s\n", VERSION);
 			return EXIT_SUCCESS;

monitor/nlmon.c

@@ -82,6 +82,8 @@
 #define BSS_CAPABILITY_APSD		(1<<11)
 #define BSS_CAPABILITY_DSSS_OFDM	(1<<13)
 
+struct nlmon *cur_nlmon;
+
 enum msg_type {
 	MSG_REQUEST,
 	MSG_RESPONSE,
@@ -99,6 +101,7 @@ struct nlmon {
 	bool nortnl;
 	bool nowiphy;
 	bool noscan;
+	bool noies;
 };
 
 struct nlmon_req {
@@ -2124,6 +2127,9 @@ static void print_ie(unsigned int level, const char *label,
 			}
 		}
 
+		if (cur_nlmon && cur_nlmon->noies && tag != IE_TYPE_SSID)
+			continue;
+
 		if (entry && entry->function)
 			entry->function(level + 1, entry->str,
 					iter.data, iter.len);
@@ -3966,6 +3972,9 @@ static void print_management_ies(unsigned int level, const char *label,
 
 	print_ie(level, label, data, size);
 
+	if (cur_nlmon && cur_nlmon->noies)
+		return;
+
 	wsc_data = ie_tlv_extract_wsc_payload(data, size, &wsc_len);
 	if (wsc_data) {
 		print_wsc_attributes(level + 1, "WSC Payload",
@@ -6325,6 +6334,8 @@ static void print_message(struct nlmon *nlmon, const struct timeval *tv,
 	case MSG_REQUEST:
 	case MSG_RESULT:
 	case MSG_EVENT:
+		cur_nlmon = nlmon;
+
 		switch (cmd) {
 		case NL80211_CMD_CONTROL_PORT_FRAME:
 			print_attributes(0, control_port_attr_table, data, len);
@@ -6332,6 +6343,8 @@ static void print_message(struct nlmon *nlmon, const struct timeval *tv,
 		default:
 			print_attributes(0, attr_table, data, len);
 		}
+
+		cur_nlmon = NULL;
 		break;
 	case MSG_RESPONSE:
 		print_field("Status: %s (%d)", strerror(status), status);
@@ -7692,6 +7705,7 @@ struct nlmon *nlmon_open(const char *ifname, uint16_t id, const char *pathname,
 	nlmon->nortnl = config->nortnl;
 	nlmon->nowiphy = config->nowiphy;
 	nlmon->noscan = config->noscan;
+	nlmon->noies = config->noies;
 
 	l_io_set_read_handler(nlmon->io, nlmon_receive, nlmon, NULL);
 	l_io_set_read_handler(nlmon->pae_io, pae_receive, nlmon, NULL);

monitor/nlmon.h

@@ -29,6 +29,7 @@ struct nlmon_config {
 	bool nortnl;
 	bool nowiphy;
 	bool noscan;
+	bool noies;
 };
 
 struct nlmon *nlmon_open(const char *ifname, uint16_t id, const char *pathname,