ref: 82435c350a1d3530c87ea88ada68e984fc6b9b80
dir: /sys/src/cmd/ip/snoopy/ospf.c/
#include <u.h> #include <libc.h> #include <ip.h> #include <libsec.h> #include "dat.h" #include "protos.h" /* * OSPF packets */ typedef struct Ospfpkt Ospfpkt; struct Ospfpkt { uchar version; uchar type; uchar length[2]; uchar router[4]; uchar area[4]; uchar sum[2]; uchar autype[2]; uchar auth[8]; uchar data[1]; }; #define OSPF_HDRSIZE 24 enum { OSPFhello= 1, OSPFdd= 2, OSPFlsrequest= 3, OSPFlsupdate= 4, OSPFlsack= 5, }; char *ospftype[] = { [OSPFhello] "hello", [OSPFdd] "data definition", [OSPFlsrequest] "link state request", [OSPFlsupdate] "link state update", [OSPFlsack] "link state ack", }; char* ospfpkttype(int x) { static char type[16]; if(x > 0 && x <= OSPFlsack) return ospftype[x]; sprint(type, "type %d", x); return type; } char* ospfauth(Ospfpkt *ospf) { static char auth[100]; switch(ospf->type){ case 0: return "no authentication"; case 1: sprint(auth, "password(%8.8ux %8.8ux)", NetL(ospf->auth), NetL(ospf->auth+4)); break; case 2: sprint(auth, "crypto(plen %d id %d dlen %d)", NetS(ospf->auth), ospf->auth[2], ospf->auth[3]); break; default: sprint(auth, "auth%d(%8.8ux %8.8ux)", NetS(ospf->autype), NetL(ospf->auth), NetL(ospf->auth+4)); } return auth; } typedef struct Ospfhello Ospfhello; struct Ospfhello { uchar mask[4]; uchar interval[2]; uchar options; uchar pri; uchar deadint[4]; uchar designated[4]; uchar bdesignated[4]; uchar neighbor[1]; }; char* seprintospfhello(char *p, char *e, void *a) { Ospfhello *h = a; return seprint(p, e, "%s(mask %V interval %d opt %ux pri %ux deadt %d designated %V bdesignated %V)", ospftype[OSPFhello], h->mask, NetS(h->interval), h->options, h->pri, NetL(h->deadint), h->designated, h->bdesignated); } enum { LSARouter= 1, LSANetwork= 2, LSASummN= 3, LSASummR= 4, LSAASext= 5 }; char *lsatype[] = { [LSARouter] "Router LSA", [LSANetwork] "Network LSA", [LSASummN] "Summary LSA (Network)", [LSASummR] "Summary LSA (Router)", [LSAASext] "LSA AS external", }; char* lsapkttype(int x) { static char type[16]; if(x > 0 && x <= LSAASext) return lsatype[x]; sprint(type, "type %d", x); return type; } /* OSPF Link State Advertisement Header */ /* rfc2178 section 12.1 */ /* data of Ospfpkt point to a 4-uchar value that is the # of LSAs */ struct OspfLSAhdr { uchar lsage[2]; uchar options; /* 0x2=stub area, 0x1=TOS routing capable */ uchar lstype; /* 1=Router-LSAs * 2=Network-LSAs * 3=Summary-LSAs (to network) * 4=Summary-LSAs (to AS boundary routers) * 5=AS-External-LSAs */ uchar lsid[4]; uchar advtrt[4]; uchar lsseqno[4]; uchar lscksum[2]; uchar lsalen[2]; /* includes the 20 byte lsa header */ }; struct Ospfrt { uchar linkid[4]; uchar linkdata[4]; uchar typ; uchar numtos; uchar metric[2]; }; struct OspfrtLSA { struct OspfLSAhdr hdr; uchar netmask[4]; }; struct OspfntLSA { struct OspfLSAhdr hdr; uchar netmask[4]; uchar attrt[4]; }; /* Summary Link State Advertisement info */ struct Ospfsumm { uchar flag; /* always zero */ uchar metric[3]; }; struct OspfsummLSA { struct OspfLSAhdr hdr; uchar netmask[4]; struct Ospfsumm lsa; }; /* AS external Link State Advertisement info */ struct OspfASext { uchar flag; /* external */ uchar metric[3]; uchar fwdaddr[4]; uchar exrttag[4]; }; struct OspfASextLSA { struct OspfLSAhdr hdr; uchar netmask[4]; struct OspfASext lsa; }; /* OSPF Link State Update Packet */ struct OspfLSupdpkt { uchar lsacnt[4]; union { uchar hdr[1]; struct OspfrtLSA rt[1]; struct OspfntLSA nt[1]; struct OspfsummLSA sum[1]; struct OspfASextLSA as[1]; }; }; char* seprintospflsaheader(char *p, char *e, struct OspfLSAhdr *h) { return seprint(p, e, "age %d opt %ux type %ux lsid %V adv_rt %V seqno %ux c %4.4ux l %d", NetS(h->lsage), h->options&0xff, h->lstype, h->lsid, h->advtrt, NetL(h->lsseqno), NetS(h->lscksum), NetS(h->lsalen)); } /* OSPF Database Description Packet */ struct OspfDDpkt { uchar intMTU[2]; uchar options; uchar bits; uchar DDseqno[4]; struct OspfLSAhdr hdr[1]; /* LSA headers... */ }; char* seprintospfdatadesc(char *p, char *e, void *a, int len) { int nlsa, i; struct OspfDDpkt *g; g = (struct OspfDDpkt *)a; nlsa = len/sizeof(struct OspfLSAhdr); for (i=0; i<nlsa; i++) { p = seprint(p, e, "lsa%d(", i); p = seprintospflsaheader(p, e, &(g->hdr[i])); p = seprint(p, e, ")"); } return seprint(p, e, ")"); } char* seprintospflsupdate(char *p, char *e, void *a, int len) { int nlsa, i; struct OspfLSupdpkt *g; struct OspfLSAhdr *h; g = (struct OspfLSupdpkt *)a; nlsa = NetL(g->lsacnt); h = (struct OspfLSAhdr *)(g->hdr); p = seprint(p, e, "%d-%s(", nlsa, ospfpkttype(OSPFlsupdate)); switch(h->lstype) { case LSARouter: { /* struct OspfrtLSA *h; */ } break; case LSANetwork: { struct OspfntLSA *h; for (i=0; i<nlsa; i++) { h = &(g->nt[i]); p = seprint(p, e, "lsa%d(", i); p = seprintospflsaheader(p, e, &(h->hdr)); p = seprint(p, e, " mask %V attrt %V)", h->netmask, h->attrt); } } break; case LSASummN: case LSASummR: { struct OspfsummLSA *h; for (i=0; i<nlsa; i++) { h = &(g->sum[i]); p = seprint(p, e, "lsa%d(", i); p = seprintospflsaheader(p, e, &(h->hdr)); p = seprint(p, e, " mask %V met %d)", h->netmask, Net3(h->lsa.metric)); } } break; case LSAASext: { struct OspfASextLSA *h; for (i=0; i<nlsa; i++) { h = &(g->as[i]); p = seprint(p, e, " lsa%d(", i); p = seprintospflsaheader(p, e, &(h->hdr)); p = seprint(p, e, " mask %V extflg %1.1ux met %d fwdaddr %V extrtflg %ux)", h->netmask, h->lsa.flag, Net3(h->lsa.metric), h->lsa.fwdaddr, NetL(h->lsa.exrttag)); } } break; default: p = seprint(p, e, "Not an LS update, lstype %d ", h->lstype); p = seprint(p, e, " %.*H", len>64?64:len, a); break; } return seprint(p, e, ")"); } char* seprintospflsack(char *p, char *e, void *a, int len) { int nlsa, i; struct OspfLSAhdr *h; h = (struct OspfLSAhdr *)a; nlsa = len/sizeof(struct OspfLSAhdr); p = seprint(p, e, "%d-%s(", nlsa, ospfpkttype(OSPFlsack)); for (i=0; i<nlsa; i++) { p = seprint(p, e, " lsa%d(", i); p = seprintospflsaheader(p, e, &(h[i])); p = seprint(p, e, ")"); } return seprint(p, e, ")"); } int p_seprint(Msg *m) { Ospfpkt *ospf; int len, x; char *p, *e; len = m->pe - m->ps; if(len < OSPF_HDRSIZE) return -1; p = m->p; e = m->e; /* adjust packet size */ ospf = (Ospfpkt*)m->ps; x = NetS(ospf->length); if(x < len) return -1; x -= OSPF_HDRSIZE; p = seprint(p, e, "ver=%d type=%d len=%d r=%V a=%V c=%4.4ux %s ", ospf->version, ospf->type, x, ospf->router, ospf->area, NetS(ospf->sum), ospfauth(ospf)); switch (ospf->type) { case OSPFhello: p = seprintospfhello(p, e, ospf->data); break; case OSPFdd: p = seprintospfdatadesc(p, e, ospf->data, x); break; case OSPFlsrequest: p = seprint(p, e, " %s->", ospfpkttype(ospf->type)); goto Default; case OSPFlsupdate: p = seprintospflsupdate(p, e, ospf->data, x); break; case OSPFlsack: p = seprintospflsack(p, e, ospf->data, x); break; default: Default: p = seprint(p, e, " data=%.*H", x>64?64:x, ospf->data); } m->p = p; m->pr = nil; return 0; } Proto ospf = { "ospf", nil, nil, p_seprint, nil, nil, nil, defaultframer, };