Add manually triggered network scan command

commandline.c

@@ -1874,6 +1874,33 @@ int app_reverse_lookup(int argc, const char *const *argv, struct command_line_op
   return 0;
 }
 
+int app_network_scan(int argc, const char *const *argv, struct command_line_option *o, void *context)
+{
+  overlay_mdp_frame mdp;
+  bzero(&mdp,sizeof(mdp));
+  
+  mdp.packetTypeAndFlags=MDP_SCAN;
+  
+  struct overlay_mdp_scan *scan = (struct overlay_mdp_scan *)&mdp.raw;
+  const char *address;
+  if (cli_arg(argc, argv, o, "address", &address, NULL, NULL) == -1)
+    return -1;
+  
+  if (address){
+    DEBUGF("Parsing arg %s", address);
+    if (!inet_aton(address, &scan->addr))
+      return WHY("Unable to parse the address");
+  }else
+    DEBUGF("Scanning local networks");
+  
+  overlay_mdp_send(&mdp,MDP_AWAITREPLY,5000);
+  if (mdp.packetTypeAndFlags!=MDP_ERROR)
+    return -1;
+  cli_puts(mdp.error.message);
+  cli_delim("\n");
+  return mdp.error.error;
+}
+
 /* NULL marks ends of command structure.
    "<anystring>" marks an arg that can take any value.
    "[<anystring>]" marks an optional arg that can take any value.
@@ -1963,6 +1990,8 @@ struct command_line_option command_line_options[]={
    "Return identity of all known peers as URIs"},
   {app_route_print, {"route","print",NULL},0,
   "Print the routing table"},
+  {app_network_scan, {"scan","[<address>]",NULL},0,
+    "Scan the network for serval peers. If no argument is supplied, all local addresses will be scanned."},
   {app_node_info,{"node","info","<sid>",NULL},0,
    "Return routing information about a SID"},
   {app_count_peers,{"peer","count",NULL},0,

constants.h

@@ -147,6 +147,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #define MDP_ROUTING_TABLE 7
 #define MDP_NODEINFO 8
 #define MDP_GOODBYE 9
+#define MDP_SCAN 10
 
 // These are back-compatible with the old values of 'mode' when it was 'selfP'
 #define MDP_ADDRLIST_MODE_ROUTABLE_PEERS 0

mdp_client.c

@@ -294,6 +294,9 @@ int overlay_mdp_relevant_bytes(overlay_mdp_frame *mdp)
     case MDP_BIND:
       len=(&mdp->raw[0] - (char *)mdp) + sizeof(sockaddr_mdp);
       break;
+    case MDP_SCAN:
+      len=(&mdp->raw[0] - (char *)mdp) + sizeof(struct overlay_mdp_scan);
+      break;
     case MDP_ERROR: 
       /* This formulation is used so that we don't copy any bytes after the
        end of the string, to avoid information leaks */

mdp_client.h

@@ -21,6 +21,16 @@
 
 #include "serval.h"
 
+struct overlay_route_record{
+  unsigned char sid[SID_SIZE];
+  int reachable;
+  unsigned char neighbour[SID_SIZE];
+};
+
+struct overlay_mdp_scan{
+  struct in_addr addr;
+};
+
 /* Client-side MDP function */
 extern int mdp_client_socket;
 int overlay_mdp_client_init();

overlay_interface.c

@@ -484,6 +484,9 @@ overlay_interface_init(char *name, struct in_addr src_addr, struct in_addr netma
     char option_name[64];
     snprintf(option_name, sizeof(option_name), "mdp.%s.tick_ms", (*name=='>'?name+1:name));
     interface->tick_ms = confValueGetInt64Range(option_name, interface->tick_ms, 1LL, 3600000LL);
+    
+    snprintf(option_name, sizeof(option_name), "interface.%s.default_route", (*name=='>'?name+1:name));
+    interface->default_route=confValueGetBoolean(option_name,0);
   }
   
   // disable announcements and other broadcasts if tick_ms=0. 

overlay_mdp.c

@@ -859,6 +859,39 @@ static int routing_table(struct subscriber *subscriber, void *context){
   return 0;
 }
 
+struct scan_state{
+  struct sched_ent alarm;
+  overlay_interface *interface;
+  uint32_t current;
+  uint32_t last;
+};
+struct scan_state scans[OVERLAY_MAX_INTERFACES];
+
+static void overlay_mdp_scan(struct sched_ent *alarm)
+{
+  struct sockaddr_in addr={
+    .sin_family=AF_INET,
+    .sin_port=htons(PORT_DNA),
+  };
+  struct scan_state *state = (struct scan_state *)alarm;
+  
+  while(state->current <= state->last){
+    addr.sin_addr.s_addr=htonl(state->current);
+    if (overlay_send_probe(NULL, addr, state->interface))
+      break;
+    state->current++;
+  }
+  
+  if (state->current <= state->last){
+    alarm->alarm=gettime_ms()+500;
+    schedule(alarm);
+  }else{
+    state->interface=NULL;
+    state->current=0;
+    state->last=0;
+  }
+}
+
 void overlay_mdp_poll(struct sched_ent *alarm)
 {
   if (alarm->poll.revents & POLLIN) {
@@ -905,7 +938,7 @@ void overlay_mdp_poll(struct sched_ent *alarm)
 	  
 	}
 	return;
-	  
+      
       case MDP_GETADDRS:
 	{
 	  overlay_mdp_frame mdpreply;
@@ -955,6 +988,52 @@ void overlay_mdp_poll(struct sched_ent *alarm)
 	}
 	break;
 	  
+      case MDP_SCAN:
+	{
+	  struct overlay_mdp_scan *scan = (struct overlay_mdp_scan *)&mdp->raw;
+	  time_ms_t start=gettime_ms();
+	  
+	  if (scan->addr.s_addr==0){
+	    int i=0;
+	    for (i=0;i<OVERLAY_MAX_INTERFACES;i++){
+	      // skip any interface that is already being scanned
+	      if (scans[i].interface)
+		continue;
+	      
+	      struct overlay_interface *interface = &overlay_interfaces[i];
+	      if (interface->state!=INTERFACE_STATE_UP)
+		continue;
+	      
+	      scans[i].interface = interface;
+	      scans[i].current = ntohl(interface->address.sin_addr.s_addr & interface->netmask.s_addr);
+	      scans[i].last = ntohl(interface->broadcast_address.sin_addr.s_addr);
+	      scans[i].alarm.alarm=start;
+	      scans[i].alarm.function=overlay_mdp_scan;
+	      start+=100;
+	      schedule(&scans[i].alarm);
+	    }
+	  }else{
+	    struct overlay_interface *interface = overlay_interface_find(scan->addr);
+	    if (!interface){
+	      overlay_mdp_reply_error(alarm->poll.fd,recvaddr_un,recvaddrlen, 1, "Unable to find matching interface");
+	      return;
+	    }
+	    int i = interface - overlay_interfaces;
+	    
+	    if (!scans[i].interface){
+	      scans[i].interface = interface;
+	      scans[i].current = ntohl(scan->addr.s_addr);
+	      scans[i].last = ntohl(scan->addr.s_addr);
+	      scans[i].alarm.alarm=start;
+	      scans[i].alarm.function=overlay_mdp_scan;
+	      schedule(&scans[i].alarm);
+	    }
+	  }
+	  
+	  overlay_mdp_reply_ok(alarm->poll.fd,recvaddr_un,recvaddrlen,"Scan initiated");
+	}
+	break;
+	
       default:
 	/* Client is not allowed to send any other frame type */
 	WARNF("Unsupported MDP frame type: %d", mdp_type);

serval.h

@@ -560,12 +560,6 @@ typedef struct overlay_mdp_addrlist {
   unsigned char sids[MDP_MAX_SID_REQUEST][SID_SIZE];
 } overlay_mdp_addrlist;
 
-struct overlay_route_record{
-  unsigned char sid[SID_SIZE];
-  int reachable;
-  unsigned char neighbour[SID_SIZE];
-};
-
 typedef struct overlay_mdp_nodeinfo {
   unsigned char sid[SID_SIZE];
   int sid_prefix_length; /* must be long enough to be unique */