>Synopsis: eigrpd: multiple issues
>Category: user
>Environment:
System : OpenBSD 7.8
Details : OpenBSD 7.8 (GENERIC) #54: Sun Oct 12 12:45:58 MDT 2025
[email protected]:/usr/src/sys/arch/amd64/compile/GENERIC
Architecture: OpenBSD.amd64
Machine : amd64
>Description:
eigrpd: multiple issues
>How-To-Repeat:
At first, eigrp daemon exited with error just after start:
# cat eigrpd.conf
address-family ipv4 {
autonomous-system 1 {
interface vio1
interface vio2
}
}
# eigrpd -d -v -f eigrpd.conf
startup
...
fatal in eigrpe: in_cksum: packet too big
...
waiting for children to terminate
terminating
I found that in_cksum() is called with uninitialized data
because of swapped source and destination in ibuf_from_ibuf().
I fixed that. Then the daemon started but was unable to make
an adjacency with a Cisco router. Cisco complained on wrong
checksum in incoming EIGRP packets. In fact, the checksums were
in wrong byte order. I added a call to htons(). Then eigrpd and
Cisco made an adjacency and exchanged routes.
Unfortunately, redistribution of static routes didn't work.
It looks like children processes get configuration with
empty redist_list despite of that list being correctly filled
in the master process. I was unable to fix this issue.
>Fix:
(partial fix)
--- packet.c
+++ packet.c
@@ -175,7 +175,7 @@ send_packet(struct eigrp_iface *ei, struct nbr *nbr,
uint32_t flags,
rtp_ack_stop_timer(nbr);
}
- ibuf_from_ibuf(buf, &ebuf);
+ ibuf_from_ibuf(&ebuf, buf);
if (ibuf_get(&ebuf, &eigrp_hdr, sizeof(eigrp_hdr)) == -1)
fatalx("send_packet: get hdr failed");
@@ -189,7 +189,7 @@ send_packet(struct eigrp_iface *ei, struct nbr *nbr,
uint32_t flags,
if (ibuf_set_n16(buf, offsetof(struct eigrp_hdr, chksum), 0) == -1)
fatalx("send_packet: set of chksum failed");
if (ibuf_set_n16(buf, offsetof(struct eigrp_hdr, chksum),
- in_cksum(ibuf_data(buf), ibuf_size(buf))) == -1)
+ htons(in_cksum(ibuf_data(buf), ibuf_size(buf)))) == -1)
fatalx("send_packet: set of chksum failed");
/* log packet being sent */
