Date: Thu, 22 Jul 1999 16:22:13 -0400 (EDT) From: Jim Flowers <jflowers@ezo.net> To: Bill Paul <wpaul@ctr.columbia.edu> Cc: skip-info@skip-vpn.org, freebsd-security@freebsd.org Subject: Re: wi driver with SKIP Message-ID: <Pine.BSI.3.91.990722123700.26379A-100000@lily.ezo.net> In-Reply-To: <199907221412.KAA26519@startide.ctr.columbia.edu>
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Thanks for the response. Sorry for the hypertext. A new portable not fully configured yet. See comments below. Jim Flowers <jflowers@ezo.net> #4 ISP on C|NET, #1 in Ohio On Thu, 22 Jul 1999, Bill Paul wrote: > > Hm. My understanding is that in an Ethernet II frame, the type field > represents the payload type in the frame, which can be IP, ARP, reverse > ARP, to name a few. If SKIP packets have a different kind of header > than IP, then the frame type will be different from IP (which is 0x800). SKIP encapsulates the original packet and prepends a new IP header and recalculates the header checksum. The 8-bit protocol field is 57. Should look like a normal IP packet to the link layer. Just not TCP or UDP. Note the problem is in the outbound direction so I don't quite see how the Ethernet II type field would be wrong. Isn't this determined by the wi driver and hardware? > > As to why it works when the packets originate on another interface, > I'm not sure. I can only assume that in that case, the packets are > tunneled through IP, in which case the ethertype is correct and > wi_start() passes them correctly. Well, I think I misrepresented this. What works is to install SKIP on a FreeBSD Ethernet interface (lnc1) and then connect this to a WaveLAN/EC converter that then communicates with the Windows 98 skiphost. No wi driver involved but it is what leads me to think that the W98 implementation is OK. Before I try hacking the driver, I think I should try two FreeBSD machines over wi drivers and use a bpf packet sniffer to see whats going to / coming from the link layer. > > Oh yeah: and turn off 'send HTML and plain text mail' in your > browser/mail client/whatever. :) Sorry. I'll let you know. Jim To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message
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