sys/src/cmd/ip/snoopy/pppoe_disc.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <ip.h>
   4 #include "dat.h"
   5 #include "protos.h"
   6
   7 typedef struct Hdr Hdr;
   8 struct Hdr {
   9         uchar verstype;
  10         uchar code;
  11         uchar sessid[2];
  12         uchar length[2];        /* of payload */
  13 };
  14 enum
  15 {
  16         HDRSIZE = 1+1+2+2
  17 };
  18
  19 static Mux p_mux[] =
  20 {
  21         {"ppp",         0,      } ,
  22         {0}
  23 };
  24
  25 enum
  26 {
  27         Overs,
  28         Otype,
  29         Ocode,
  30         Osess,
  31 };
  32
  33 static Field p_fields[] =
  34 {
  35         {"v",   Fnum,   Overs,  "version",      } ,
  36         {"t",   Fnum,   Otype,  "type", } ,
  37         {"c",   Fnum,   Ocode,  "code" } ,
  38         {"s",   Fnum,   Osess,  "sessid" } ,
  39         {0}
  40 };
  41
  42 static void
  43 p_compilesess(Filter *f)
  44 {
  45 //      Mux *m;
  46
  47         if(f->op == '='){
  48                 compile_cmp(pppoe_sess.name, f, p_fields);
  49                 return;
  50         }
  51 /*
  52         for(m = p_mux; m->name != nil; m++)
  53                 if(strcmp(f->s, m->name) == 0){
  54                         f->pr = m->pr;
  55                         f->ulv = m->val;
  56                         f->subop = Ot;
  57                         return;
  58                 }
  59 */
  60         sysfatal("unknown pppoe field or protocol: %s", f->s);
  61 }
  62 static void
  63 p_compiledisc(Filter *f)
  64 {
  65 //      Mux *m;
  66
  67         if(f->op == '='){
  68                 compile_cmp(pppoe_disc.name, f, p_fields);
  69                 return;
  70         }
  71 /*
  72         for(m = p_mux; m->name != nil; m++)
  73                 if(strcmp(f->s, m->name) == 0){
  74                         f->pr = m->pr;
  75                         f->ulv = m->val;
  76                         f->subop = Ot;
  77                         return;
  78                 }
  79 */
  80         sysfatal("unknown pppoe field or protocol: %s", f->s);
  81 }
  82
  83 static int
  84 p_filter(Filter *f, Msg *m)
  85 {
  86         Hdr *h;
  87
  88         if(m->pe - m->ps < HDRSIZE)
  89                 return 0;
  90
  91         h = (Hdr*)m->ps;
  92         m->ps += HDRSIZE;
  93
  94         switch(f->subop){
  95         case Overs:
  96                 return (h->verstype>>4) == f->ulv;
  97         case Otype:
  98                 return (h->verstype&0xF) == f->ulv;
  99         case Ocode:
 100                 return h->code == f->ulv;
 101         case Osess:
 102                 return NetS(h->sessid) == f->ulv;
 103         }
 104         return 0;
 105 }
 106
 107 /* BUG: print all the discovery types */
 108 static int
 109 p_seprintdisc(Msg *m)
 110 {
 111         Hdr *h;
 112         int len;
 113
 114         len = m->pe - m->ps;
 115         if(len < HDRSIZE)
 116                 return -1;
 117
 118         h = (Hdr*)m->ps;
 119         m->ps += HDRSIZE;
 120
 121         m->pr = nil;
 122
 123         m->p = seprint(m->p, m->e, "v=%d t=%d c=0x%x s=0x%ux, len=%d",
 124                 h->verstype>>4, h->verstype&0xF, h->code, NetS(h->sessid), NetS(h->length));
 125
 126         return 0;
 127 }
 128
 129 static int
 130 p_seprintsess(Msg *m)
 131 {
 132         Hdr *h;
 133         int len;
 134
 135         len = m->pe - m->ps;
 136         if(len < HDRSIZE)
 137                 return -1;
 138
 139         h = (Hdr*)m->ps;
 140         m->ps += HDRSIZE;
 141
 142         /* this will call ppp for me */
 143         demux(p_mux, 0, 0, m, &dump);
 144
 145         m->p = seprint(m->p, m->e, "v=%d t=%d c=0x%x s=0x%ux, len=%d",
 146                 h->verstype>>4, h->verstype&0xF, h->code, NetS(h->sessid), NetS(h->length));
 147
 148         return 0;
 149 }
 150
 151 Proto pppoe_disc =
 152 {
 153         "pppoe_disc",
 154         p_compiledisc,
 155         p_filter,
 156         p_seprintdisc,
 157         p_mux,
 158         "%lud",
 159         p_fields,
 160         defaultframer
 161 };
 162
 163 Proto pppoe_sess =
 164 {
 165         "pppoe_sess",
 166         p_compilesess,
 167         p_filter,
 168         p_seprintsess,
 169         p_mux,
 170         "%lud",
 171         p_fields,
 172         defaultframer
 173 };
 174