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#include <u.h>
#include <libc.h>
#include <ip.h>
#include "dat.h"
#include "protos.h"
typedef struct Hdr Hdr;
struct Hdr
{
uchar vihl; /* Version and header length */
uchar tos; /* Type of service */
uchar length[2]; /* packet length */
uchar id[2]; /* ip->identification */
uchar frag[2]; /* Fragment information */
uchar ttl; /* Time to live */
uchar proto; /* Protocol */
uchar cksum[2]; /* Header checksum */
uchar src[4]; /* IP source */
uchar dst[4]; /* IP destination */
};
enum
{
IPHDR = 20, /* sizeof(Iphdr) */
IP_VER = 0x40, /* Using IP version 4 */
IP_DF = 0x4000, /* Don't fragment */
IP_MF = 0x2000, /* More fragments */
};
static Mux p_mux[] =
{
{ "icmp", 1, },
{ "igmp", 2, },
{ "ggp", 3, },
{ "ip", 4, },
{ "st", 5, },
{ "tcp", 6, },
{ "ucl", 7, },
{ "egp", 8, },
{ "igp", 9, },
{ "bbn-rcc-mon", 10, },
{ "nvp-ii", 11, },
{ "pup", 12, },
{ "argus", 13, },
{ "emcon", 14, },
{ "xnet", 15, },
{ "chaos", 16, },
{ "udp", 17, },
{ "mux", 18, },
{ "dcn-meas", 19, },
{ "hmp", 20, },
{ "prm", 21, },
{ "xns-idp", 22, },
{ "trunk-1", 23, },
{ "trunk-2", 24, },
{ "leaf-1", 25, },
{ "leaf-2", 26, },
{ "rdp", 27, },
{ "irtp", 28, },
{ "iso-tp4", 29, },
{ "netblt", 30, },
{ "mfe-nsp", 31, },
{ "merit-inp", 32, },
{ "sep", 33, },
{ "3pc", 34, },
{ "idpr", 35, },
{ "xtp", 36, },
{ "ddp", 37, },
{ "idpr-cmtp", 38, },
{ "tp++", 39, },
{ "il", 40, },
{ "sip", 41, },
{ "sdrp", 42, },
{ "sip-sr", 43, },
{ "sip-frag", 44, },
{ "idrp", 45, },
{ "rsvp", 46, },
{ "gre", 47, },
{ "mhrp", 48, },
{ "bna", 49, },
{ "sipp-esp", 50, },
{ "sipp-ah", 51, },
{ "i-nlsp", 52, },
{ "swipe", 53, },
{ "nhrp", 54, },
{ "any", 61, },
{ "cftp", 62, },
{ "any", 63, },
{ "sat-expak", 64, },
{ "kryptolan", 65, },
{ "rvd", 66, },
{ "ippc", 67, },
{ "any", 68, },
{ "sat-mon", 69, },
{ "visa", 70, },
{ "ipcv", 71, },
{ "cpnx", 72, },
{ "cphb", 73, },
{ "wsn", 74, },
{ "pvp", 75, },
{ "br-sat-mon", 76, },
{ "sun-nd", 77, },
{ "wb-mon", 78, },
{ "wb-expak", 79, },
{ "iso-ip", 80, },
{ "vmtp", 81, },
{ "secure-vmtp", 82, },
{ "vines", 83, },
{ "ttp", 84, },
{ "nsfnet-igp", 85, },
{ "dgp", 86, },
{ "tcf", 87, },
{ "igrp", 88, },
{ "ospf", 89, },
{ "sprite-rpc", 90, },
{ "larp", 91, },
{ "mtp", 92, },
{ "ax.25", 93, },
{ "ipip", 94, },
{ "micp", 95, },
{ "scc-sp", 96, },
{ "etherip", 97, },
{ "encap", 98, },
{ "any", 99, },
{ "gmtp", 100, },
{ "rudp", 254, },
{ 0 }
};
enum
{
Os, // source
Od, // destination
Osd, // source or destination
Ot, // type
};
static Field p_fields[] =
{
{"s", Fv4ip, Os, "source address", } ,
{"d", Fv4ip, Od, "destination address", } ,
{"a", Fv4ip, Osd, "source|destination address",} ,
{"sd", Fv4ip, Osd, "source|destination address",} ,
{"t", Fnum, Ot, "sub protocol number", } ,
{0}
};
static void
p_compile(Filter *f)
{
Mux *m;
if(f->op == '='){
compile_cmp(ip.name, f, p_fields);
return;
}
for(m = p_mux; m->name != nil; m++)
if(strcmp(f->s, m->name) == 0){
f->pr = m->pr;
f->ulv = m->val;
f->subop = Ot;
return;
}
sysfatal("unknown ip field or protocol: %s", f->s);
}
static int
p_filter(Filter *f, Msg *m)
{
Hdr *h;
if(m->pe - m->ps < IPHDR)
return 0;
h = (Hdr*)m->ps;
m->ps += ((h->vihl&0xf)<<2);
switch(f->subop){
case Os:
return NetL(h->src) == f->ulv;
case Od:
return NetL(h->dst) == f->ulv;
case Osd:
return NetL(h->src) == f->ulv || NetL(h->dst) == f->ulv;
case Ot:
return h->proto == f->ulv;
}
return 0;
}
static int
p_seprint(Msg *m)
{
Hdr *h;
int f;
int len;
if(m->pe - m->ps < IPHDR)
return -1;
h = (Hdr*)m->ps;
/* next protocol, just dump unless this is the first fragment */
m->pr = &dump;
f = NetS(h->frag);
if((f & ~(IP_DF|IP_MF)) == 0)
demux(p_mux, h->proto, h->proto, m, &dump);
/* truncate the message if there's extra */
len = NetS(h->length);
if(len < m->pe - m->ps)
m->pe = m->ps + len;
/* next header */
m->ps += ((h->vihl&0xf)<<2);
m->p = seprint(m->p, m->e, "s=%V d=%V id=%4.4ux frag=%4.4ux ttl=%3d pr=%d ln=%d",
h->src, h->dst,
NetS(h->id),
NetS(h->frag),
h->ttl,
h->proto,
NetS(h->length)
);
return 0;
}
Proto ip =
{
"ip",
p_compile,
p_filter,
p_seprint,
p_mux,
"%lud",
p_fields,
defaultframer,
};
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