net/http: Allow use of non-standard TCP/IP ports

Allow the use of HTTP servers listening on ports other 80. This is done
with an extension to the http notation:

  (http[,server[,port]])

 - or -

  (http[,server[:port]])

Signed-off-by: Stephen Balousek <sbalousek@wickedloop.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

docs/grub.texi

@@ -3011,6 +3011,39 @@ environment variable @samp{net_default_server} is used.
 Before using the network drive, you must initialize the network.
 @xref{Network}, for more information.
 
+For the @samp{http} network protocol, @code{@var{server}} may specify a
+port number other than the default value of @samp{80}. The server name
+and port number are separated by either @samp{,} or @samp{:}.
+For IPv6 addresses, the server name and port number may only be separated
+by @samp{,}.
+
+@itemize @bullet
+@item
+@code{(http,@var{server},@var{port})}
+
+@item
+@code{(http,@var{server}:@var{port})}
+@end itemize
+
+These examples all reference an @samp{http} server at address
+@samp{192.0.2.1} listening on the non-standard port of @samp{3000}.
+In these examples, the DNS name @samp{grub.example.com} is resolved
+to @samp{192.0.2.1}.
+
+@example
+(http,grub.example.com,3000)
+(http,grub.example.com:3000)
+(http,192.0.2.1,3000)
+(http,192.0.2.1:3000)
+@end example
+
+Referencing an @samp{http} server over IPv6 on the non-standard
+port of @samp{3000} would look like this:
+
+@example
+(http,2001:db8::1,3000)
+@end example
+
 If you boot GRUB from a CD-ROM, @samp{(cd)} is available. @xref{Making
 a GRUB bootable CD-ROM}, for details.
 

grub-core/net/http.c

@@ -312,6 +312,10 @@ http_establish (struct grub_file *file, grub_off_t offset, int initial)
   int i;
   struct grub_net_buff *nb;
   grub_err_t err;
+  char *server_name;
+  char *port_string;
+  const char *port_string_end;
+  unsigned long port_number;
 
   nb = grub_netbuff_alloc (GRUB_NET_TCP_RESERVE_SIZE
 			   + sizeof ("GET ") - 1
@@ -390,10 +394,42 @@ http_establish (struct grub_file *file, grub_off_t offset, int initial)
   grub_netbuff_put (nb, 2);
   grub_memcpy (ptr, "\r\n", 2);
 
-  data->sock = grub_net_tcp_open (file->device->net->server,
+  port_string = grub_strrchr (file->device->net->server, ',');
-				  HTTP_PORT, http_receive,
+  if (port_string == NULL)
+    {
+      /* If ",port" is not found in the http server string, look for ":port". */
+      port_string = grub_strrchr (file->device->net->server, ':');
+      /* For IPv6 addresses, the ":port" syntax is not supported and ",port" must be used. */
+      if (port_string != NULL && grub_strchr (file->device->net->server, ':') != port_string)
+	  port_string = NULL;
+    }
+  if (port_string != NULL)
+    {
+      port_number = grub_strtoul (port_string + 1, &port_string_end, 10);
+      if (*(port_string + 1) == '\0' || *port_string_end != '\0')
+	  return grub_error (GRUB_ERR_BAD_NUMBER, N_("non-numeric or invalid port number `%s'"), port_string + 1);
+      if (port_number == 0 || port_number > 65535)
+	  return grub_error (GRUB_ERR_OUT_OF_RANGE, N_("port number `%s' not in the range of 1 to 65535"), port_string + 1);
+
+      server_name = grub_strdup (file->device->net->server);
+      if (server_name == NULL)
+	  return grub_errno;
+      server_name[port_string - file->device->net->server] = '\0';
+    }
+  else
+    {
+      port_number = HTTP_PORT;
+      server_name = file->device->net->server;
+    }
+
+  data->sock = grub_net_tcp_open (server_name,
+				  port_number, http_receive,
 				  http_err, NULL,
 				  file);
+
+  if (server_name != file->device->net->server)
+      grub_free (server_name);
+
   if (!data->sock)
     {
       grub_netbuff_free (nb);