Implement initial connection protocol.

Author: larsbrinkhoff

src/ncp.c

@@ -54,6 +54,15 @@
 #define ERR_SOCKET      4 //Request on a non-existent socket.
 #define ERR_CONNECT     5 //Socket (link) not connected.
 
+#define ICP_NONE            0
+#define ICP_SERVER_LISTEN   1
+#define ICP_SERVER_STR      2
+#define ICP_SERVER_SOCKET   3
+#define ICP_CLIENT_RTS     11
+#define ICP_CLIENT_ALL     12
+#define ICP_CLIENT_CLS     13
+#define ICP_CLIENT_RTS2    14
+
 #define CONNECTIONS 20
 
 static int fd;
@@ -71,6 +80,7 @@ struct
 {
   client_t client;
   int host;
+  int icp;
   struct { int link, size; uint32_t lsock, rsock; } rcv, snd;
 } connection[CONNECTIONS];
 
@@ -168,6 +178,7 @@ static void destroy (int i)
     connection[i].snd.size = connection[i].rcv.size = -1;
   connection[i].rcv.lsock = connection[i].rcv.rsock =
     connection[i].snd.lsock = connection[i].snd.rsock = 0;
+  connection[i].icp = ICP_NONE;
 }
 
 static void send_imp (int flags, int type, int destination, int link, int id,
@@ -277,7 +288,7 @@ void ncp_rts (uint8_t destination, uint32_t lsock, uint32_t rsock, uint8_t link)
 void ncp_all (uint8_t destination, uint8_t link, uint16_t msg_space, uint32_t bit_space)
 {
   packet[22] = link;
-  packet[23] = msg_space >> 16;
+  packet[23] = msg_space >> 8;
   packet[24] = msg_space;
   packet[25] = bit_space >> 24;
   packet[26] = bit_space >> 16;
@@ -438,20 +449,34 @@ static int process_rts (uint8_t source, uint8_t *data)
 {
   int i;
   uint32_t lsock, rsock;
+  uint8_t link;
+
   rsock = sock (&data[0]);
   lsock = sock (&data[4]);
+  link = data[8];
 
-  fprintf (stderr, "NCP: Received RTS %u:%u from %03o.\n",
-           lsock, rsock, source);
+  fprintf (stderr, "NCP: Received RTS sockets %u:%u link %u from %03o.\n",
+           rsock, lsock, link, source);
 
-  if (data[8] < LINK_MIN || data[8] > LINK_MAX) {
+  if (link < LINK_MIN || link > LINK_MAX) {
     ncp_err (source, ERR_PARAM, data - 1, 10);
     return 9;
   }
 
   if (find_listen (lsock) == -1) {
     i = find_sockets (source, lsock, rsock);
     if (i == -1) {
+      i = find_socket (source, lsock-3);
+      if (i != -1) {
+        fprintf (stderr, "NCP: ICP from %03o, RTS %u:%u link %u.\n",
+                 source, rsock, lsock, link);
+        i = make_open (source, 0, 0, lsock, rsock);
+        connection[i].snd.link = link;
+        connection[i].snd.size = 8;
+        ncp_str (source, lsock, rsock, connection[i].snd.size);
+        return 9;
+      }
+
       fprintf (stderr, "NCP: Not listening to %u, no outgoing RFC, rejecting.\n", lsock);
       ncp_cls (source, lsock, rsock);
       return 9;
@@ -468,18 +493,23 @@ static int process_rts (uint8_t source, uint8_t *data)
       fprintf (stderr, "NCP: Listening to %u: connection %d.\n", lsock, i);
     }
   }
-  connection[i].snd.link = data[8]; //Send link.
-  if (connection[i].rcv.size == -1) {
+  connection[i].snd.link = link; //Send link.
+  if (connection[i].icp == ICP_SERVER_LISTEN) {
+    connection[i].rcv.size = 32; //Send byte size for ICP.
+    connection[i].icp = ICP_SERVER_STR;
+    ncp_str (connection[i].host, lsock, rsock, connection[i].rcv.size);
+  }
+  else if (connection[i].rcv.size == -1) {
     connection[i].rcv.size = 8; //Send byte size.
     ncp_str (connection[i].host, lsock, rsock, connection[i].rcv.size);
     if (connection[i].rcv.link != -1) {
       fprintf (stderr, "NCP: Completing incoming RFC.\n");
-      reply_listen (source, connection[i].snd.lsock, i);
+      //reply_listen (source, connection[i].snd.lsock, i);
     }
   } else {
     if (connection[i].snd.size != -1) {
       fprintf (stderr, "NCP: Completing outgoing RFC.\n");
-      reply_open (source, connection[i].rcv.rsock, i);
+      //reply_open (source, connection[i].rcv.rsock, i);
     }
   }
 
@@ -490,25 +520,39 @@ static int process_str (uint8_t source, uint8_t *data)
 {
   int i;
   uint32_t lsock, rsock;
+  uint8_t size;
+
   rsock = sock (&data[0]);
   lsock = sock (&data[4]);
-
-  fprintf (stderr, "NCP: Received STR %u:%u from %03o.\n",
-           lsock, rsock, source);
-
-  if (data[8] < LINK_MIN || data[8] > LINK_MAX) {
-    ncp_err (source, ERR_PARAM, data - 1, 10);
-    return 9;
-  }
+  size = data[8];
 
   if (find_listen (lsock) == -1) {
     i = find_sockets (source, lsock, rsock);
     if (i == -1) {
+      i = find_socket (source, lsock-2);
+      if (i != -1) {
+        fprintf (stderr, "NCP: ICP STR %u:%u size %u.\n",
+                 rsock, lsock, size);
+        i = make_open (source, lsock, rsock, 0, 0);
+        connection[i].rcv.size = size;
+        connection[i].rcv.link = 43;
+        ncp_rts (source, lsock, rsock, connection[i].rcv.link);
+        reply_open (source, 23, i);
+        return 9;
+      }
+
       fprintf (stderr, "NCP: Not listening to %u, no outgoing RFC, rejecting.\n", lsock);
       ncp_cls (source, lsock, rsock);
       return 9;
     }
-    fprintf (stderr, "NCP: Outgoing RFC socket %u.\n", lsock);
+    if (connection[i].icp == ICP_CLIENT_RTS) {
+      fprintf (stderr, "NCP: Received from %03o ICP STR %u:%u, size %u.\n",
+               source, rsock, lsock, size);
+      connection[i].rcv.size = size;
+      connection[i].icp = ICP_CLIENT_ALL;
+      ncp_all (source, connection[i].rcv.link, 1, 200);
+      return 9;
+    }
   } else {
     i = find_socket (source, lsock - 1);
     if (i == -1) {
@@ -520,7 +564,7 @@ static int process_str (uint8_t source, uint8_t *data)
       fprintf (stderr, "NCP: Listening to %u: connection %d.\n", lsock, i);
     }
   }
-  connection[i].snd.size = data[8]; //Receive byte size.
+  connection[i].snd.size = size; //Receive byte size.
   if (connection[i].rcv.link == -1) {
     connection[i].rcv.link = 42; //Receive link.
     ncp_rts (connection[i].host, lsock, rsock, connection[i].rcv.link);
@@ -531,7 +575,7 @@ static int process_str (uint8_t source, uint8_t *data)
   } else {
     if (connection[i].snd.link != -1) {
       fprintf (stderr, "NCP: Completing outgoing RFC.\n");
-      reply_open (source, connection[i].rcv.rsock, i);
+      //reply_open (source, connection[i].rcv.rsock, i);
     }
   }
 
@@ -546,9 +590,21 @@ static int process_cls (uint8_t source, uint8_t *data)
   lsock = sock (&data[4]);
   i = find_sockets (source, lsock, rsock);
   if (i == -1) {
+    fprintf (stderr, "NCP: Remote tried to close %u:%u which does not exist.\n",
+             lsock, rsock);
     ncp_err (source, ERR_SOCKET, data - 1, 9);
     return 8;
   }
+
+  if (connection[i].icp == ICP_CLIENT_CLS) {
+    ncp_rts (source,
+             connection[i].rcv.lsock,
+             connection[i].rcv.rsock,
+             connection[i].rcv.link);
+    connection[i].icp = ICP_CLIENT_RTS2;
+    return 8;
+  }
+
   if (connection[i].rcv.lsock == lsock)
     connection[i].rcv.lsock = connection[i].rcv.rsock = 0;
   if (connection[i].snd.lsock == lsock)
@@ -568,7 +624,7 @@ static int process_cls (uint8_t source, uint8_t *data)
     if (connection[i].rcv.lsock == 0 && connection[i].snd.lsock == 0) {
       fprintf (stderr, "NCP: Connection %u closed by remote.\n", i);
       destroy (i);
-      reply_close (i);
+      //reply_close (i);
     }
   }
 
@@ -578,12 +634,26 @@ static int process_cls (uint8_t source, uint8_t *data)
 static int process_all (uint8_t source, uint8_t *data)
 {
   int i;
+  uint8_t link = data[0];
+
   fprintf (stderr, "NCP: Received ALL from %03o, link %u.\n",
-           source, data[0]);
-  i = find_link (source, data[0]);
-  if (i == -1)
+           source, link);
+  i = find_link (source, link);
+  if (i == -1) {
     ncp_err (source, ERR_SOCKET, data - 1, 10);
-  return 9;
+  } else if (connection[i].icp == ICP_SERVER_STR) {
+    uint8_t tmp[4];
+    uint32_t s = 0200;
+    tmp[0] = (s >> 24) & 0xFF;
+    tmp[1] = (s >> 16) & 0xFF;
+    tmp[2] = (s >>  8) & 0xFF;
+    tmp[3] = (s >>  0) & 0xFF;
+    fprintf (stderr, "NCP: Send socket %u for ICP.\n", s);
+    send_imp (0, IMP_REGULAR, connection[i].host, connection[i].snd.link,
+              0, 0, &tmp, 4);
+    connection[i].icp = ICP_SERVER_SOCKET;
+  }
+  return 7;
 }
 
 static int process_gvb (uint8_t source, uint8_t *data)
@@ -656,7 +726,6 @@ static int process_erp (uint8_t source, uint8_t *data)
 {
   fprintf (stderr, "NCP: recieved ERP %03o from %03o.\n",
            *data, source);
-  hosts[source].flags |= HOST_ALIVE;
   reply_echo (source, *data, 0x10);
   hosts[source].echo.len = 0;
   return 1;
@@ -804,6 +873,16 @@ static void process_regular (uint8_t *packet, int length)
     }
     length = 2 * (length - 2);
     fprintf (stderr, "NCP: Connection %u, length %u.\n", i, length);
+
+    if (connection[i].icp == ICP_CLIENT_ALL) {
+      uint32_t s = sock (&packet[5]);
+      fprintf (stderr, "NCP: ICP link %u socket %u.\n", link, s);
+      ncp_cls (source, connection[i].rcv.lsock, connection[i].rcv.rsock);
+      connection[i].icp = ICP_CLIENT_CLS;
+      connection[i].snd.rsock = s;
+      return;
+    }
+
     reply_read (i, packet + 4, length);
   }
 }
@@ -997,8 +1076,8 @@ static void app_open (void)
   int i;
 
   socket = app[2] << 24 | app[3] << 16 | app[4] << 8 | app[5];
-  fprintf (stderr, "NCP: Application open sockets %u,%u on host %03o.\n",
-           socket, socket+1, host);
+  fprintf (stderr, "NCP: Application open socket %u on host %03o.\n",
+           socket, host);
 
   if ((hosts[host].flags & HOST_ALIVE) == 0) {
     // We haven't communicated with this host yet.
@@ -1007,17 +1086,15 @@ static void app_open (void)
   }
 
   // Initiate a connection.
-  i = make_open (host, 1002, socket, 1003, socket+1);
+  i = make_open (host, 1002, socket, 0, 0);
   connection[i].rcv.link = 42; //Receive link.
-  connection[i].rcv.size = 8;  //Send byte size.
   memcpy (&connection[i].client.addr, &client, len);
   connection[i].client.len = len;
 
-  // Send RFC messages.
+  // Send first ICP RTS.
   ncp_rts (connection[i].host, connection[i].rcv.lsock,
            connection[i].rcv.rsock, connection[i].rcv.link);
-  ncp_str (connection[i].host, connection[i].snd.lsock,
-           connection[i].snd.rsock, connection[i].rcv.size);
+  connection[i].icp = ICP_CLIENT_RTS;
 }
 
 static void app_listen (void)
@@ -1041,6 +1118,7 @@ static void app_listen (void)
   listening[i].sock = socket;
   memcpy (&connection[i].client.addr, &client, len);
   connection[i].client.len = len;
+  connection[i].icp = ICP_SERVER_LISTEN;
 }
 
 static void app_read (void)