[PATCH v2] http: Allow use of non-standard TCP/IP ports

[Stephen Balousek]

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>
---

Hi Daniel,

Happy New Year!

I apologize for the long delay. I really wanted to test the changes
for an HTTP server over IPv6, but not knowing much about setting up an
IPv6 network made for a pretty steep learning curve! Anyway, please
find attached a new version of the patch for allowing the use of
non-standard HTTP server ports.

I added some comments to the code for parsing the port number from an
IPv6 address, and added relevant examples to the INFO document.

Also, you mentioned:

    I think it should be "port_number == GRUB_ULONG_MAX" instead of
    "port_number == 0" here.

I took a closer look at  grub_strtoul() and that function actually
returns zero (0) when a non-numeric value is encounteded in the
string. So, functionally, I think these changes are correct.

Thank you for your patience and all the help!
- Steve


 docs/grub.texi       | 33 +++++++++++++++++++++++++++++++++
 grub-core/net/http.c | 39 +++++++++++++++++++++++++++++++++++++--
 2 files changed, 70 insertions(+), 2 deletions(-)

diff --git a/docs/grub.texi b/docs/grub.texi
index f8b4b3b21..a95d86f95 100644
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -3004,6 +3004,39 @@ 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{192.168.0.100} listening on the non-standard port of @samp{3000}.
+In these examples, the DNS name @samp{grub.example.com} is resolved
+to @samp{192.168.0.100}.
+
+@example
+(http,grub.example.com,3000)
+(http,grub.example.com:3000)
+(http,192.168.0.100,3000)
+(http,192.168.0.100:3000)
+@end example
+
+Referencing an @samp{http} server over IPv6 on the non-standard
+port of @samp{3000} would look like this:
+
+@example
+(http,2001:dead:beef::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.
 
diff --git a/grub-core/net/http.c b/grub-core/net/http.c
index b616cf40b..f457cd010 100644
--- a/grub-core/net/http.c
+++ b/grub-core/net/http.c
@@ -312,6 +312,9 @@ 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;
+  unsigned long port_number;
 
   nb = grub_netbuff_alloc (GRUB_NET_TCP_RESERVE_SIZE
                           + sizeof ("GET ") - 1
@@ -390,10 +393,42 @@ 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,
-                                 HTTP_PORT, http_receive,
+  port_string = grub_strrchr (file->device->net->server, ',');
+  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, 0, 10);
+      if (port_number == 0 && grub_errno == GRUB_ERR_BAD_NUMBER)
+         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);
-- 
2.34.1