vbatts/grub
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

bootp: ignore gateway_ip (relay) field.

Browse source 
From RFC1542:

   The 'giaddr' field is rather poorly named.  It exists to facilitate
   the transfer of BOOTREQUEST messages from a client, through BOOTP
   relay agents, to servers on different networks than the client.
   Similarly, it facilitates the delivery of BOOTREPLY messages from the
   servers, through BOOTP relay agents, back to the client.  In no case
   does it represent a general IP router to be used by the client.  A
   BOOTP client MUST set the 'giaddr' field to zero (0.0.0.0) in all
   BOOTREQUEST messages it generates.

   A BOOTP client MUST NOT interpret the 'giaddr' field of a BOOTREPLY
   message to be the IP address of an IP router.  A BOOTP client SHOULD
   completely ignore the contents of the 'giaddr' field in BOOTREPLY
   messages.

Leave code ifdef'd out for the time being in case we see regression.

Suggested by: Rink Springer <rink@rink.nu>
Closes: 43396
This commit is contained in:
Andrei Borzenkov 2015-05-17 22:38:30 +03:00
parent 2498dc7a3a
commit a666c8bd18
2 changed files with 11 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
docs/grub.texi
View file

@ -5162,8 +5162,10 @@ by @var{shortname} which can be used to remove it (@pxref{net_del_route}).
Perform configuration of @var{card} using DHCP protocol. If no card name
is specified, try to configure all existing cards. If configuration was
successful, interface with name @var{card}@samp{:dhcp} and configured
address is added to @var{card}. If server provided gateway information in
DHCP ACK packet, it is added as route entry with the name @var{card}@samp{:dhcp:gw}. Additionally the following DHCP options are recognized and processed:
address is added to @var{card}.
@comment If server provided gateway information in
@comment DHCP ACK packet, it is added as route entry with the name @var{card}@samp{:dhcp:gw}.
Additionally the following DHCP options are recognized and processed:
@table @samp
@item 1 (Subnet Mask)

7
grub-core/net/bootp.c
View file

@ -157,6 +157,12 @@ grub_net_configure_by_dhcp_ack (const char *name,
hwaddr.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
inter = grub_net_add_addr (name, card, &addr, &hwaddr, flags);
#if 0
/* This is likely based on misunderstanding. gateway_ip refers to
address of BOOTP relay and should not be used after BOOTP transaction
is complete.
See RFC1542, 3.4 Interpretation of the 'giaddr' field
*/
if (bp->gateway_ip)
{
grub_net_network_level_netaddress_t target;
@ -178,6 +184,7 @@ grub_net_configure_by_dhcp_ack (const char *name,
target.ipv4.masksize = 32;
grub_net_add_route (name, target, inter);
}
#endif
if (size > OFFSET_OF (boot_file, bp))
grub_env_set_net_property (name, "boot_file", bp->boot_file,