From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Andrzej Kacprowski <andrzej.kacprowski@intel.com>
Date: Fri, 21 Apr 2017 09:20:38 +0200
Subject: [PATCH] Use xid to match DHCP replies

Transaction identifier (xid) from DHCP request
packet is stored in network level interface and used
to match request with the responses it generates.

Resolves: rhbz#1370642

Signed-off-by: Andrzej Kacprowski <andrzej.kacprowski@intel.com>
---
 grub-core/net/bootp.c | 3 ++-
 grub-core/net/ip.c    | 1 +
 include/grub/net.h    | 3 ++-
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/grub-core/net/bootp.c b/grub-core/net/bootp.c
index 7df7f55110e..dfdf7e08d90 100644
--- a/grub-core/net/bootp.c
+++ b/grub-core/net/bootp.c
@@ -769,7 +769,8 @@ grub_cmd_bootp (struct grub_command *cmd __attribute__ ((unused)),
 	      grub_errno = GRUB_ERR_NONE;
 	      t = 0;
 	    }
-	  pack->ident = grub_cpu_to_be32 (t);
+	  pack->xid = grub_cpu_to_be32 (t);
+	  ifaces[j].dhcp_xid = pack->xid;
 	  pack->seconds = grub_cpu_to_be16 (t);
 
 	  grub_memcpy (&pack->mac_addr, &ifaces[j].hwaddress.mac, 6); 
diff --git a/grub-core/net/ip.c b/grub-core/net/ip.c
index 5a609544403..9e7930caa03 100644
--- a/grub-core/net/ip.c
+++ b/grub-core/net/ip.c
@@ -271,6 +271,7 @@ handle_dgram (struct grub_net_buff *nb,
 	FOR_NET_NETWORK_LEVEL_INTERFACES (inf)
 	  if (inf->card == card
 	      && inf->address.type == GRUB_NET_NETWORK_LEVEL_PROTOCOL_DHCP_RECV
+	      && inf->dhcp_xid == bootp->xid
 	      && inf->hwaddress.type == GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET
 	      && grub_memcmp (inf->hwaddress.mac, &bootp->mac_addr,
 			      sizeof (inf->hwaddress.mac)) == 0)
diff --git a/include/grub/net.h b/include/grub/net.h
index bd930f4dd8c..b1bc23048f1 100644
--- a/include/grub/net.h
+++ b/include/grub/net.h
@@ -279,6 +279,7 @@ struct grub_net_network_level_interface
   grub_net_interface_flags_t flags;
   struct grub_net_bootp_packet *dhcp_ack;
   grub_size_t dhcp_acklen;
+  grub_uint32_t dhcp_xid;
   void *data;
 };
 
@@ -405,7 +406,7 @@ struct grub_net_bootp_packet
   grub_uint8_t hw_type;		/* hardware type.  */
   grub_uint8_t hw_len;		/* hardware addr len.  */
   grub_uint8_t gate_hops;	/* zero it.  */
-  grub_uint32_t ident;		/* random number chosen by client.  */
+  grub_uint32_t xid;		/* transaction id chosen by client.  */
   grub_uint16_t seconds;	/* seconds since did initial bootstrap.  */
   grub_uint16_t flags;
   grub_uint32_t	client_ip;