ref: a1c3c34c70431447a89fbe08c3475dbfaee7b672
dir: /sys/src/cmd/ip/snoopy/dhcp.c/
#include <u.h> #include <libc.h> #include <ip.h> #include "dat.h" #include "protos.h" #include "../dhcp.h" /* * convert a byte array to hex */ static char hex(int x) { if(x < 10) return x + '0'; return x - 10 + 'a'; } static char* phex(char *p, char *e, char *tag, uchar *o, int n) { p = seprint(p, e, "%s=", tag); for(; p+2 < e && n > 0; n--){ *p++ = hex(*o >> 4); *p++ = hex(*o & 0xf); o++; } return p; } static char* pstring(char *p, char *e, char *tag, uchar *o, int n) { char msg[256]; if(n > sizeof msg - 1) n = sizeof msg - 1; memmove(msg, o, n); msg[n] = 0; return seprint(p, e, "%s=%s", tag, msg); } static char* pint(char *p, char *e, char *tag, uchar *o, int n) { int x; x = *(char*)o++; for(; n > 1; n--) x = x<<8 | *o++; return seprint(p, e, "%s=%d", tag, x); } static char* puint(char *p, char *e, char *tag, uchar *o, int n) { uint x; x = *o++; for(; n > 1; n--) x = x<<8 | *o++; return seprint(p, e, "%s=%ud", tag, x); } static char* pserver(char *p, char *e, char *tag, uchar *o, int n) { int i; p = seprint(p, e, "%s=(", tag); i = 0; while(n >= 4){ if(i++ > 0) p = seprint(p, e, " "); p = seprint(p, e, "%V", o); n -= 4; o += 4; } p = seprint(p, e, ")"); return p; } static char* pcfroutes(char *p, char *e, char *tag, uchar *o, int n) { int i; p = seprint(p, e, "%s=(", tag); i = 0; while(n >= 8){ if(i++ > 0) p = seprint(p, e, " "); p = seprint(p, e, "%V→%V", o, o+4); o += 8; n -= 8; } p = seprint(p, e, ")"); return p; } static char* pclroutes(char *p, char *e, char *tag, uchar *o, int n) { uchar addr[4]; int i, nbits, nocts; p = seprint(p, e, "%s=(", tag); i = 0; while(n >= 5){ nbits = *o++; n--; nocts = nbits <= 32 ? (nbits+7)/8 : 4; if(n < nocts+4) break; memset(addr, 0, 4); memmove(addr, o, nocts); o += nocts; n -= nocts; if(i++ > 0) p = seprint(p, e, " "); p = seprint(p, e, "%V/%d→%V", addr, nbits, o); o += 4; n -= 4; } p = seprint(p, e, ")"); return p; } static char *dhcptype[256] = { [Discover] "Discover", [Offer] "Offer", [Request] "Request", [Decline] "Decline", [Ack] "Ack", [Nak] "Nak", [Release] "Release", [Inform] "Inform", }; static char* ptype(char *p, char *e, uchar val) { char *x; x = dhcptype[val]; if(x != nil) return seprint(p, e, "t=%s", x); else return seprint(p, e, "t=%d", val); } static int p_seprint(Msg *m) { int i, n, code; uchar *o, *ps; char *p, *e; char msg[64]; /* no next proto */ m->pr = nil; p = m->p; e = m->e; ps = m->ps; while(ps < m->pe){ code = *ps++; if(code == 255) break; if(code == 0) continue; /* ignore anything that's too long */ n = *ps++; o = ps; ps += n; if(ps > m->pe) break; switch(code){ case ODipaddr: /* requested ip address */ p = pserver(p, e, "ipaddr", o, n); break; case ODlease: /* requested lease time */ p = pint(p, e, "lease", o, n); break; case ODtype: p = ptype(p, e, *o); break; case ODserverid: p = pserver(p, e, "serverid", o, n); break; case ODmessage: p = pstring(p, e, "message", o, n); break; case ODmaxmsg: p = puint(p, e, "maxmsg", o, n); break; case ODclientid: p = phex(p, e, "clientid", o, n); break; case ODparams: p = seprint(p, e, " requested=("); for(i = 0; i < n; i++){ if(i != 0) p = seprint(p, e, " "); p = seprint(p, e, "%ud", o[i]); } p = seprint(p, e, ")"); break; case ODvendorclass: p = pstring(p, e, "vendorclass", o, n); break; case OBmask: p = pserver(p, e, "mask", o, n); break; case OBtimeoff: p = pint(p, e, "timeoff", o, n); break; case OBrouter: p = pserver(p, e, "router", o, n); break; case OBtimeserver: p = pserver(p, e, "timesrv", o, n); break; case OBnameserver: p = pserver(p, e, "namesrv", o, n); break; case OBdnserver: p = pserver(p, e, "dnssrv", o, n); break; case OBlogserver: p = pserver(p, e, "logsrv", o, n); break; case OBcookieserver: p = pserver(p, e, "cookiesrv", o, n); break; case OBlprserver: p = pserver(p, e, "lprsrv", o, n); break; case OBimpressserver: p = pserver(p, e, "impresssrv", o, n); break; case OBrlserver: p = pserver(p, e, "rlsrv", o, n); break; case OBhostname: p = pstring(p, e, "hostname", o, n); break; case OBbflen: break; case OBdumpfile: p = pstring(p, e, "dumpfile", o, n); break; case OBdomainname: p = pstring(p, e, "domname", o, n); break; case OBrootserver: p = pserver(p, e, "rootsrv", o, n); break; case OBrootpath: p = pstring(p, e, "rootpath", o, n); break; case OBextpath: p = pstring(p, e, "extpath", o, n); break; case OBipforward: p = phex(p, e, "ipforward", o, n); break; case OBnonlocal: p = phex(p, e, "nonlocal", o, n); break; case OBpolicyfilter: p = phex(p, e, "policyfilter", o, n); break; case OBmaxdatagram: p = phex(p, e, "maxdatagram", o, n); break; case OBttl: p = puint(p, e, "ttl", o, n); break; case OBpathtimeout: p = puint(p, e, "pathtimeout", o, n); break; case OBpathplateau: p = phex(p, e, "pathplateau", o, n); break; case OBmtu: p = puint(p, e, "mtu", o, n); break; case OBsubnetslocal: p = pserver(p, e, "subnet", o, n); break; case OBbaddr: p = pserver(p, e, "baddr", o, n); break; case OBdiscovermask: p = pserver(p, e, "discovermsak", o, n); break; case OBsupplymask: p = pserver(p, e, "rousupplymaskter", o, n); break; case OBdiscoverrouter: p = pserver(p, e, "discoverrouter", o, n); break; case OBrsserver: p = pserver(p, e, "rsrouter", o, n); break; case OBstaticroutes: p = pcfroutes(p, e, "cf-routes", o, n); break; case ODclasslessroutes: p = pclroutes(p, e, "cl-routes", o, n); break; case OBtrailerencap: p = phex(p, e, "trailerencap", o, n); break; case OBarptimeout: p = puint(p, e, "arptimeout", o, n); break; case OBetherencap: p = phex(p, e, "etherencap", o, n); break; case OBtcpttl: p = puint(p, e, "tcpttl", o, n); break; case OBtcpka: p = puint(p, e, "tcpka", o, n); break; case OBtcpkag: p = phex(p, e, "tcpkag", o, n); break; case OBnisdomain: p = pstring(p, e, "nisdomain", o, n); break; case OBniserver: p = pserver(p, e, "nisrv", o, n); break; case OBntpserver: p = pserver(p, e, "ntpsrv", o, n); break; case OBvendorinfo: p = phex(p, e, "vendorinfo", o, n); break; case OBnetbiosns: p = pserver(p, e, "biosns", o, n); break; case OBnetbiosdds: p = phex(p, e, "biosdds", o, n); break; case OBnetbiostype: p = phex(p, e, "biostype", o, n); break; case OBnetbiosscope: p = phex(p, e, "biosscope", o, n); break; case OBxfontserver: p = pserver(p, e, "fontsrv", o, n); break; case OBxdispmanager: p = pserver(p, e, "xdispmgr", o, n); break; case OBnisplusdomain: p = pstring(p, e, "nisplusdomain", o, n); break; case OBnisplusserver: p = pserver(p, e, "nisplussrv", o, n); break; case OBhomeagent: p = pserver(p, e, "homeagent", o, n); break; case OBsmtpserver: p = pserver(p, e, "smtpsrv", o, n); break; case OBpop3server: p = pserver(p, e, "pop3srv", o, n); break; case OBnntpserver: p = pserver(p, e, "ntpsrv", o, n); break; case OBwwwserver: p = pserver(p, e, "wwwsrv", o, n); break; case OBfingerserver: p = pserver(p, e, "fingersrv", o, n); break; case OBircserver: p = pserver(p, e, "ircsrv", o, n); break; case OBstserver: p = pserver(p, e, "stsrv", o, n); break; case OBstdaserver: p = pserver(p, e, "stdasrv", o, n); break; case OBend: goto out; default: snprint(msg, sizeof msg, "T%ud", code); p = phex(p, e, msg, o, n); break; } if(*ps != OBend) p = seprint(p, e, " "); } out: m->p = p; m->ps = ps; return 0; } Proto dhcp = { "dhcp", nil, nil, p_seprint, nil, nil, nil, defaultframer, };