ref: 28f4567ba615c4036c079021392825757ef2a008
dir: /sys/src/cmd/ip/snoopy/eapol.c/
#include <u.h> #include <libc.h> #include <ip.h> #include "dat.h" #include "protos.h" typedef struct Hdr Hdr; struct Hdr { uchar vi; /* version */ uchar type; uchar len[2]; /* length of data following this header */ }; enum { EAPOLHDR= 4, /* sizeof(Hdr) */ /* eapol types */ Eap = 0, Start, Logoff, Key, AsfAlert, }; enum { Ot, /* type */ }; static Mux p_mux[] = { { "eap", Eap, }, { "eapol_start", Start, }, { "eapol_logoff", Logoff, }, { "eapol_key", Key, }, { "asf_alert", AsfAlert, }, { 0 } }; static void p_compile(Filter *f) { Mux *m; 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 eapol field or type: %s", f->s); } static int p_filter(Filter *f, Msg *m) { Hdr *h; if(m->pe - m->ps < EAPOLHDR) return 0; h = (Hdr*)m->ps; /* len does not include header */ m->ps += EAPOLHDR; switch(f->subop){ case Ot: return h->type == f->ulv; } return 0; } static char* op(int i) { static char x[20]; switch(i){ case Eap: return "Eap"; case Start: return "Start"; case Logoff: return "Logoff"; case Key: return "Key"; case AsfAlert: return "AsfAlert"; default: sprint(x, "%1d", i); return x; } } static int p_seprint(Msg *m) { Hdr *h; int len; if(m->pe - m->ps < EAPOLHDR) return -1; h = (Hdr*)m->ps; /* len does not include header */ m->ps += EAPOLHDR; /* truncate the message if there's extra */ len = NetS(h->len); if(m->ps + len < m->pe) m->pe = m->ps + len; else if(m->ps+len > m->pe) return -1; /* next protocol depending on type*/ demux(p_mux, h->type, h->type, m, &dump); m->p = seprint(m->p, m->e, "type=%s version=%1d datalen=%1d", op(h->type), h->vi, len); return 0; } Proto eapol = { "eapol", p_compile, p_filter, p_seprint, p_mux, "%lud", nil, defaultframer, };