> On 8 Mar 2017, at 16:29, Jeremie Courreges-Anglas <j...@wxcvbn.org> wrote: > > > https://tools.ietf.org/html/draft-housley-etherip-01 > > still proposes a 1 byte header, the first nibble is the version (2). > The published RFC specifies version 3 and a two bytes header. > > https://tools.ietf.org/html/rfc3378 > > print-etherip.c almost gets it right when trying to interpret the > version. Here's a diff to fix it. > > Using tcpdump -envvvttt, before: > > Mar 08 04:21:03.258703 fe:e1:ba:d1:94:57 fe:e1:ba:d1:94:56 0800 134: etherip > 10.64.20.2 > 10.64.20.1 ver unknown len 100 [tos 0x10] (ttl 64, id 33731, len > 120) > Mar 08 04:21:03.259136 fe:e1:ba:d1:94:56 fe:e1:ba:d1:94:57 0800 134: etherip > 10.64.20.1 > 10.64.20.2 ver unknown len 100 [tos 0x10] (ttl 64, id 56533, len > 120) > > After: > > Mar 08 04:21:56.786890 fe:e1:ba:d1:94:57 fe:e1:ba:d1:94:56 0800 134: etherip > 10.64.20.2 > 10.64.20.1 ver 3 len 100: fe:e1:ba:d1:94:58 fe:e1:ba:d0:18:c3 > 0800 98: 10.64.64.3 > 10.64.64.1: icmp: echo request (id:9d1b seq:8359) (ttl > 255, id 7825, len 84) [tos 0x10] (ttl 64, id 61952, len 120) > Mar 08 04:21:56.787106 fe:e1:ba:d1:94:56 fe:e1:ba:d1:94:57 0800 134: etherip > 10.64.20.1 > 10.64.20.2 ver 3 len 100: fe:e1:ba:d0:18:c3 fe:e1:ba:d1:94:58 > 0800 98: 10.64.64.1 > 10.64.64.3: icmp: echo reply (id:9d1b seq:8359) (ttl > 255, id 31193, len 84) [tos 0x10] (ttl 64, id 35562, len 120) > > ok?
ok. > > > Index: print-etherip.c > =================================================================== > RCS file: /d/cvs/src/usr.sbin/tcpdump/print-etherip.c,v > retrieving revision 1.8 > diff -u -p -p -u -r1.8 print-etherip.c > --- print-etherip.c 16 Jan 2015 06:40:21 -0000 1.8 > +++ print-etherip.c 8 Mar 2017 06:21:22 -0000 > @@ -72,7 +72,7 @@ etherip_print(const u_char *bp, u_int ca > printf("etherip %s > %s ver ", ipaddr_string(&ip->ip_src), > ipaddr_string(&ip->ip_dst)); > > - switch ((*pbuf) & 0xf) { > + switch (*pbuf >> 4) { > case 2: > hlen = 1; > printf("%d", 2); > > > -- > jca | PGP : 0x1524E7EE / 5135 92C1 AD36 5293 2BDF DDCC 0DFA 74AE 1524 E7EE >