misc/175645: tcpdump incorrectly decodes pflog'ged UDP packet as ATALK

[Dmitry Dvoinikov]

>Number:         175645
>Category:       misc
>Synopsis:       tcpdump incorrectly decodes pflog'ged UDP packet as ATALK
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jan 28 09:10:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Dmitry Dvoinikov
>Release:        8.3
>Organization:
www.infosysco.ru
>Environment:
FreeBSD foo 8.3-RELEASE-p5 FreeBSD 8.3-RELEASE-p5 #1: Wed Dec 12 23:29:24 YEKT 2012     admin at foo:/opt/obj/opt/src/sys/FOO  i386
>Description:
Some UDP packet, saved by pflog, is decoded incorrectly as ATALK.

tcpdump output:

# tcpdump -r packet.pcap 
reading from file packet.pcap, link-type PFLOG (OpenBSD pflog file)
11:22:11.296532 IP 115.61.0.254 > 143.12.228.91: at-#100 5

whereas the (presumably correct) wireshark output:

Frame 1: 110 bytes on wire (880 bits), 110 bytes captured (880 bits)
PF Log IPv4 pass on ifc by rule 0
Internet Protocol Version 4, Src: 172.30.0.11 (172.30.0.11), Dst: 193.120.212.22 (193.120.212.22)
User Datagram Protocol, Src Port: 55573 (55573), Dst Port: 16605 (16605)
Data (18 bytes)


>How-To-Repeat:
openssl base64 -d > packet.pcap << EOF
1MOyoQIABAAAAAAAAAAAAHQAAAB1AAAAAwsGUVSGBABuAAAAbgAAAD0CAABpZmMA
AAAAAAAAAAAAAAAAYW5jaG9yX25hbWUAAAAAAAAAABwAAAAC/////6CGAQAAAAAA
ggUAAAEAAABFAAAuAABAAEAR+QasHgALwXjUFtkVQN0AGrhGUxUCmI8Mcz3kAFv+
ZGyAi27Z
EOF

tcpdump -r packet.pcap
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: