Rydeen, Mike said:
> Hopefully this will be a quick question/answer, but you never know.
> Looking through the Ethereal supported protocols it appears that you
> support a large part of the Fibre Channel standard protocols (FC, FC-dns,
> FC-FCS, etc). After decoding the libpcap file format, I was able to
> create a supported Ethereal file out of a series of raw Fibre Channel
> frames. Currently I am using the IP over FC (122 - 0x7a) as my link layer
> type, but it appears that this LL does not decode the Common Transport
> layer, it is only looking for the payload IP contents from the Network
> Header, SNAP and down the list.
Correct.
To quote the comment in libpcap 0.8[.x]'s "pcap-bpf.h" before the
definition of DLT_IP_OVER_FC:
/*
* This is for RFC 2625 IP-over-Fibre Channel.
*
* This is not for use with raw Fibre Channel, where the link-layer
* header starts with a Fibre Channel frame header; it's for IP-over-FC,
* where the link-layer header starts with an RFC 2625 Network_Header
* field.
*/
On the systems where DLT_IP_OVER_FC (122 - DLT_ values are given in
decimal, not hex, as the people who assign them have only 10 fingers :-))
is used, the link-layer header on packets supplied by the packet capture
mechanism is the Network_Header field specified in RFC 2625; the
lower-layer FC headers aren't supplied (perhaps because the FC card strips
them off before supplying IP-over-FC frames to the host).
> Looking through the libpcap/tcpdump code I did not really see any other LL
> type.
If you want a link-layer type for raw Fibre Channel, send mail to
"tcpdump-workers@xxxxxxxxxxx" asking for one; once one is assigned,
support for it could be added to Ethereal.
Please indicate whether the frames would start with the R_CTL field or if
there'd be some other stuff before it.
