Justin Bradford's patch for increased proxy robustness.
[u/mdw/putty] / proxy.c
diff --git a/proxy.c b/proxy.c
index b9ed548..9e3684c 100644 (file)
--- a/proxy.c
+++ b/proxy.c
@@ -22,43 +22,50 @@ void proxy_activate (Proxy_Socket p)
 {
     void *data;
     int len;
-
+    long output_before, output_after;
+    
     p->state = PROXY_STATE_ACTIVE;
 
-    /* let's try to keep extra receive events from coming through */
+    /* we want to ignore new receive events until we have sent
+     * all of our buffered receive data.
+     */
     sk_set_frozen(p->sub_socket, 1);
 
+    /* how many bytes of output have we buffered? */
+    output_before = bufchain_size(&p->pending_oob_output_data) +
+       bufchain_size(&p->pending_output_data);
+    /* and keep track of how many bytes do not get sent. */
+    output_after = 0;
+    
     /* send buffered OOB writes */
     while (bufchain_size(&p->pending_oob_output_data) > 0) {
        bufchain_prefix(&p->pending_oob_output_data, &data, &len);
-       sk_write_oob(p->sub_socket, data, len);
+       output_after += sk_write_oob(p->sub_socket, data, len);
        bufchain_consume(&p->pending_oob_output_data, len);
     }
-    bufchain_clear(&p->pending_oob_output_data);
 
     /* send buffered normal writes */
     while (bufchain_size(&p->pending_output_data) > 0) {
        bufchain_prefix(&p->pending_output_data, &data, &len);
-       sk_write(p->sub_socket, data, len);
+       output_after += sk_write(p->sub_socket, data, len);
        bufchain_consume(&p->pending_output_data, len);
     }
-    bufchain_clear(&p->pending_output_data);
+
+    /* if we managed to send any data, let the higher levels know. */
+    if (output_after < output_before)
+       plug_sent(p->plug, output_after);
 
     /* if we were asked to flush the output during
      * the proxy negotiation process, do so now.
      */
     if (p->pending_flush) sk_flush(p->sub_socket);
 
-    /* forward buffered recv data to the backend */
-    while (bufchain_size(&p->pending_input_data) > 0) {
-       bufchain_prefix(&p->pending_input_data, &data, &len);
-       plug_receive(p->plug, 0, data, len);
-       bufchain_consume(&p->pending_input_data, len);
-    }
-    bufchain_clear(&p->pending_input_data);
-
-    /* now set the underlying socket to whatever freeze state they wanted */
-    sk_set_frozen(p->sub_socket, p->freeze);
+    /* if the backend wanted the socket unfrozen, try to unfreeze.
+     * our set_frozen handler will flush buffered receive data before
+     * unfreezing the actual underlying socket.
+     */
+    if (!p->freeze)
+       sk_set_frozen((Socket)p, 0);
 }
 
 /* basic proxy socket functions */
@@ -135,6 +142,30 @@ static void sk_proxy_set_frozen (Socket s, int is_frozen)
        ps->freeze = is_frozen;
        return;
     }
+    
+    /* handle any remaining buffered recv data first */
+    if (bufchain_size(&ps->pending_input_data) > 0) {
+       ps->freeze = is_frozen;
+
+       /* loop while we still have buffered data, and while we are
+        * unfrozen. the plug_receive call in the loop could result 
+        * in a call back into this function refreezing the socket, 
+        * so we have to check each time.
+        */
+        while (!ps->freeze && bufchain_size(&ps->pending_input_data) > 0) {
+           char * data;
+           int len;
+           bufchain_prefix(&ps->pending_input_data, &data, &len);
+           plug_receive(ps->plug, 0, data, len);
+           bufchain_consume(&ps->pending_input_data, len);
+       }
+
+       /* if we're still frozen, we'll have to wait for another
+        * call from the backend to finish unbuffering the data.
+        */
+       if (ps->freeze) return;
+    }
+    
     sk_set_frozen(ps->sub_socket, is_frozen);
 }
 
@@ -314,8 +345,6 @@ Socket new_connection(SockAddr addr, char *hostname,
        ret->remote_addr = addr;
        ret->remote_port = port;
 
-       /* XXX review these initialisations, and initialise other fields
-        * in Proxy_Socket structure */
        ret->error = NULL;
        ret->pending_flush = 0;
        ret->freeze = 0;
@@ -326,7 +355,8 @@ Socket new_connection(SockAddr addr, char *hostname,
 
        ret->sub_socket = NULL;
        ret->state = PROXY_STATE_NEW;
-
+       ret->negotiate = NULL;
+       
        if (cfg.proxy_type == PROXY_HTTP) {
            ret->negotiate = proxy_http_negotiate;
        } else if (cfg.proxy_type == PROXY_SOCKS) {
@@ -1069,7 +1099,7 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
        int so = 0, eo = 0;
 
        /* we need to escape \\, \%, \r, \n, \t, \x??, \0???, 
-        * %%, %host, and %port 
+        * %%, %host, %port, %user, and %pass
         */
 
        while (cfg.proxy_telnet_command[eo] != 0) {
@@ -1177,27 +1207,40 @@ int proxy_telnet_negotiate (Proxy_Socket p, int change)
                }
            } else {
 
-               /* % escape. we recognize %%, %host, %port. anything else,
-                * we just send unescaped (including the %). */
+               /* % escape. we recognize %%, %host, %port, %user, %pass. 
+                * anything else, we just send unescaped (including the %). 
+                */
 
                if (cfg.proxy_telnet_command[eo] == '%') {
                    sk_write(p->sub_socket, "%", 1);
                    eo++;
-               } 
+               }
                else if (strnicmp(cfg.proxy_telnet_command + eo,
                                  "host", 4) == 0) {
                    char dest[64];
                    sk_getaddr(p->remote_addr, dest, 64);
                    sk_write(p->sub_socket, dest, strlen(dest));
                    eo += 4;
-               } 
+               }
                else if (strnicmp(cfg.proxy_telnet_command + eo,
                                  "port", 4) == 0) {
                    char port[8];
                    sprintf(port, "%i", p->remote_port);
                    sk_write(p->sub_socket, port, strlen(port));
                    eo += 4;
-               } 
+               }
+               else if (strnicmp(cfg.proxy_telnet_command + eo,
+                                 "user", 4) == 0) {
+                   sk_write(p->sub_socket, cfg.proxy_username, 
+                       strlen(cfg.proxy_username));
+                   eo += 4;
+               }
+               else if (strnicmp(cfg.proxy_telnet_command + eo,
+                                 "pass", 4) == 0) {
+                   sk_write(p->sub_socket, cfg.proxy_password, 
+                       strlen(cfg.proxy_password));
+                   eo += 4;
+               }
                else {
                    /* we don't escape this, so send the % now, and
                     * don't advance eo, so that we'll consider the