From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Michael Chang <[email protected]>
Date: Thu, 14 Jul 2016 18:45:14 +0800
Subject: [PATCH] bootp: Add processing DHCPACK packet from HTTP Boot

The vendor class identifier with the string "HTTPClient" is used to denote the
packet as responding to HTTP boot request. In DHCP4 config, the filename for
HTTP boot is the URL of the boot file while for PXE boot it is the path to the
boot file. As a consequence, the next-server becomes obseleted because the HTTP
URL already contains the server address for the boot file. For DHCP6 config,
there's no difference definition in existing config as dhcp6.bootfile-url can
be used to specify URL for both HTTP and PXE boot file.

This patch adds processing for "HTTPClient" vendor class identifier in DHCPACK
packet by treating it as HTTP format, not as the PXE format.

Signed-off-by: Michael Chang <[email protected]>
Signed-off-by: Ken Lin <[email protected]>
---
 grub-core/net/bootp.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++--
 include/grub/net.h    |  1 +
 2 files changed, 67 insertions(+), 2 deletions(-)

diff --git a/grub-core/net/bootp.c b/grub-core/net/bootp.c
index 242cd1f4cbd..8b6fc9f2411 100644
--- a/grub-core/net/bootp.c
+++ b/grub-core/net/bootp.c
@@ -20,6 +20,7 @@
 #include <grub/env.h>
 #include <grub/i18n.h>
 #include <grub/command.h>
+#include <grub/net.h>
 #include <grub/net/ip.h>
 #include <grub/net/netbuff.h>
 #include <grub/net/udp.h>
@@ -254,6 +255,11 @@ parse_dhcp_vendor (const char *name, const void *vend, int limit, int *mask)
                                      taglength);
           break;
 
+        case GRUB_NET_BOOTP_VENDOR_CLASS_IDENTIFIER:
+          grub_env_set_net_property (name, "vendor_class_identifier", (const char *) ptr,
+                                     taglength);
+	  break;
+
 	case GRUB_NET_BOOTP_EXTENSIONS_PATH:
           grub_env_set_net_property (name, "extensionspath", (const char *) ptr,
                                      taglength);
@@ -357,6 +363,66 @@ grub_net_configure_by_dhcp_ack (const char *name,
     }
 #endif
 
+  if (size > OFFSET_OF (vendor, bp))
+    {
+      char *cidvar;
+      const char *cid;
+
+      parse_dhcp_vendor (name, &bp->vendor, size - OFFSET_OF (vendor, bp), &mask);
+      cidvar = grub_xasprintf ("net_%s_%s", name, "vendor_class_identifier");
+      cid = grub_env_get (cidvar);
+      grub_free (cidvar);
+
+      if (cid && grub_strcmp (cid, "HTTPClient") == 0)
+	{
+	  char *proto, *ip, *pa;
+
+	  if (!dissect_url (bp->boot_file, &proto, &ip, &pa))
+	    return inter;
+
+	  grub_env_set_net_property (name, "boot_file", pa, grub_strlen (pa));
+	  if (is_def)
+	    {
+	      grub_net_default_server = grub_strdup (ip);
+	      grub_env_set ("net_default_interface", name);
+	      grub_env_export ("net_default_interface");
+	    }
+	  if (device && !*device)
+	    {
+	      *device = grub_xasprintf ("%s,%s", proto, ip);
+	      grub_print_error ();
+	    }
+	  if (path)
+	    {
+	      *path = grub_strdup (pa);
+	      grub_print_error ();
+	      if (*path)
+		{
+		  char *slash;
+		  slash = grub_strrchr (*path, '/');
+		  if (slash)
+		    *slash = 0;
+		  else
+		    **path = 0;
+		}
+	    }
+	  grub_net_add_ipv4_local (inter, mask);
+	  inter->dhcp_ack = grub_malloc (size);
+	  if (inter->dhcp_ack)
+	    {
+	      grub_memcpy (inter->dhcp_ack, bp, size);
+	      inter->dhcp_acklen = size;
+	    }
+	  else
+	    grub_errno = GRUB_ERR_NONE;
+
+	  grub_free (proto);
+	  grub_free (ip);
+	  grub_free (pa);
+	  return inter;
+	}
+    }
+
   if (size > OFFSET_OF (boot_file, bp))
     grub_env_set_net_property (name, "boot_file", bp->boot_file,
                                sizeof (bp->boot_file));
@@ -421,8 +487,6 @@ grub_net_configure_by_dhcp_ack (const char *name,
 	    **path = 0;
 	}
     }
-  if (size > OFFSET_OF (vendor, bp))
-    parse_dhcp_vendor (name, &bp->vendor, size - OFFSET_OF (vendor, bp), &mask);
   grub_net_add_ipv4_local (inter, mask);
   
   inter->dhcp_ack = grub_malloc (size);
diff --git a/include/grub/net.h b/include/grub/net.h
index 5f78b22e109..9cf6da68973 100644
--- a/include/grub/net.h
+++ b/include/grub/net.h
@@ -522,6 +522,7 @@ enum
     GRUB_NET_BOOTP_DOMAIN = 0x0f,
     GRUB_NET_BOOTP_ROOT_PATH = 0x11,
     GRUB_NET_BOOTP_EXTENSIONS_PATH = 0x12,
+    GRUB_NET_BOOTP_VENDOR_CLASS_IDENTIFIER = 0x3C,
     GRUB_NET_BOOTP_CLIENT_ID = 0x3d,
     GRUB_NET_BOOTP_CLIENT_UUID = 0x61,
     GRUB_NET_BOOTP_END = 0xff