hostapd: Support showing neighbor list through hostapd_cli

This lets one know the current neighbor list, and could be used
to populate the neighbor list of other hostapd processes.

For instance:

$ hostapd_cli -i vap0001 show_neighbor
04:f0:21:1e:ae:b0 ssid=04f0211eaeb0af190000802809 nr=04f0211eaeb0af1900008028090603022a00
$ hostapd_cli -i vap0000 set_neighbor 04:f0:21:1e:ae:b0 ssid=04f0211eaeb0af190000802809 nr=04f0211eaeb0af1900008028090603022a00
OK
$ hostapd_cli -i vap0000 show_neighbor
04:f0:21:1e:ae:b0 ssid=04f0211eaeb0af190000802809 nr=04f0211eaeb0af1900008028090603022a00
04:f0:21:c3:b2:b0 ssid=04f021c3b2b0af190000802809 nr=04f021c3b2b0af1900008028090603022a00

Signed-off-by: Ben Greear <greearb@candelatech.com>

hostapd/ctrl_iface.c

@@ -2707,6 +2707,20 @@ static int hostapd_ctrl_iface_req_beacon(struct hostapd_data *hapd,
 }
 
 
+static int hostapd_ctrl_iface_show_neighbor(struct hostapd_data *hapd,
+					    char *buf, size_t buflen)
+{
+	if (!(hapd->conf->radio_measurements[0] &
+	      WLAN_RRM_CAPS_NEIGHBOR_REPORT)) {
+		wpa_printf(MSG_ERROR,
+			   "CTRL: SHOW_NEIGHBOR: Neighbor report is not enabled");
+		return -1;
+	}
+
+	return hostapd_neighbor_show(hapd, buf, buflen);
+}
+
+
 static int hostapd_ctrl_iface_set_neighbor(struct hostapd_data *hapd, char *buf)
 {
 	struct wpa_ssid_value ssid;
@@ -3255,6 +3269,9 @@ static int hostapd_ctrl_iface_receive_process(struct hostapd_data *hapd,
 	} else if (os_strncmp(buf, "SET_NEIGHBOR ", 13) == 0) {
 		if (hostapd_ctrl_iface_set_neighbor(hapd, buf + 13))
 			reply_len = -1;
+	} else if (os_strcmp(buf, "SHOW_NEIGHBOR") == 0) {
+		reply_len = hostapd_ctrl_iface_show_neighbor(hapd, reply,
+							     reply_size);
 	} else if (os_strncmp(buf, "REMOVE_NEIGHBOR ", 16) == 0) {
 		if (hostapd_ctrl_iface_remove_neighbor(hapd, buf + 16))
 			reply_len = -1;

hostapd/hostapd_cli.c

@@ -1312,6 +1312,13 @@ static int hostapd_cli_cmd_set_neighbor(struct wpa_ctrl *ctrl, int argc,
 }
 
 
+static int hostapd_cli_cmd_show_neighbor(struct wpa_ctrl *ctrl, int argc,
+					 char *argv[])
+{
+	return wpa_ctrl_command(ctrl, "SHOW_NEIGHBOR");
+}
+
+
 static int hostapd_cli_cmd_remove_neighbor(struct wpa_ctrl *ctrl, int argc,
 					   char *argv[])
 {
@@ -1622,6 +1629,8 @@ static const struct hostapd_cli_cmd hostapd_cli_commands[] = {
 	{ "set_neighbor", hostapd_cli_cmd_set_neighbor, NULL,
 	  "<addr> <ssid=> <nr=> [lci=] [civic=] [stat]\n"
 	  "  = add AP to neighbor database" },
+	{ "show_neighbor", hostapd_cli_cmd_show_neighbor, NULL,
+	  "  = show neighbor database entries" },
 	{ "remove_neighbor", hostapd_cli_cmd_remove_neighbor, NULL,
 	  "<addr> [ssid=<hex>] = remove AP from neighbor database" },
 	{ "req_lci", hostapd_cli_cmd_req_lci, hostapd_complete_stations,

src/ap/neighbor_db.c

@@ -34,6 +34,60 @@ hostapd_neighbor_get(struct hostapd_data *hapd, const u8 *bssid,
 }
 
 
+int hostapd_neighbor_show(struct hostapd_data *hapd, char *buf, size_t buflen)
+{
+	struct hostapd_neighbor_entry *nr;
+	char *pos, *end;
+
+	pos = buf;
+	end = buf + buflen;
+
+	dl_list_for_each(nr, &hapd->nr_db, struct hostapd_neighbor_entry,
+			 list) {
+		int ret;
+		char nrie[2 * 255 + 1];
+		char lci[2 * 255 + 1];
+		char civic[2 * 255 + 1];
+		char ssid[SSID_MAX_LEN * 2 + 1];
+
+		ssid[0] = '\0';
+		wpa_snprintf_hex(ssid, sizeof(ssid), nr->ssid.ssid,
+				 nr->ssid.ssid_len);
+
+		nrie[0] = '\0';
+		if (nr->nr)
+			wpa_snprintf_hex(nrie, sizeof(nrie),
+					 wpabuf_head(nr->nr),
+					 wpabuf_len(nr->nr));
+
+		lci[0] = '\0';
+		if (nr->lci)
+			wpa_snprintf_hex(lci, sizeof(lci),
+					 wpabuf_head(nr->lci),
+					 wpabuf_len(nr->lci));
+
+		civic[0] = '\0';
+		if (nr->civic)
+			wpa_snprintf_hex(civic, sizeof(civic),
+					 wpabuf_head(nr->civic),
+					 wpabuf_len(nr->civic));
+
+		ret = os_snprintf(pos, end - pos, MACSTR
+				  " ssid=%s%s%s%s%s%s%s%s\n",
+				  MAC2STR(nr->bssid), ssid,
+				  nr->nr ? " nr=" : "", nrie,
+				  nr->lci ? " lci=" : "", lci,
+				  nr->civic ? " civic=" : "", civic,
+				  nr->stationary ? " stat" : "");
+		if (os_snprintf_error(end - pos, ret))
+			break;
+		pos += ret;
+	}
+
+	return pos - buf;
+}
+
+
 static void hostapd_neighbor_clear_entry(struct hostapd_neighbor_entry *nr)
 {
 	wpabuf_free(nr->nr);

src/ap/neighbor_db.h

@@ -13,6 +13,7 @@
 struct hostapd_neighbor_entry *
 hostapd_neighbor_get(struct hostapd_data *hapd, const u8 *bssid,
 		     const struct wpa_ssid_value *ssid);
+int hostapd_neighbor_show(struct hostapd_data *hapd, char *buf, size_t buflen);
 int hostapd_neighbor_set(struct hostapd_data *hapd, const u8 *bssid,
 			 const struct wpa_ssid_value *ssid,
 			 const struct wpabuf *nr, const struct wpabuf *lci,