ref: 163dccbac04a3c9ab132005ebb4a96a0e0baec0b
dir: /sys/src/cmd/ip/dhcpd/ndb.c/
/* * this currently only works for ethernet bootp's -- presotto */ #include <u.h> #include <libc.h> #include <ip.h> #include <bio.h> #include <ndb.h> #include "dat.h" static Ndb *db; char *ndbfile; /* * open ndbfile as db if not already open. also check for stale data * and reload as needed. */ static Ndb * opendb(void) { static ulong lastcheck; /* check no more often than once every minute */ if(db == nil) { db = ndbopen(ndbfile); if(db != nil) lastcheck = now; } else if(now >= lastcheck + 60) { if (ndbchanged(db)) ndbreopen(db); lastcheck = now; } return db; } Iplifc* findlifc(uchar *ip) { uchar x[IPaddrlen]; Ipifc *ifc; Iplifc *lifc; for(ifc = ipifcs; ifc; ifc = ifc->next){ for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){ if(lifc->net[0] == 0) continue; maskip(ip, lifc->mask, x); if(memcmp(x, lifc->net, IPaddrlen) == 0) return lifc; } } return nil; } int forme(uchar *ip) { Ipifc *ifc; Iplifc *lifc; for(ifc = ipifcs; ifc; ifc = ifc->next){ for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next) if(memcmp(ip, lifc->ip, IPaddrlen) == 0) return 1; } return 0; } uchar noetheraddr[6]; static void setipaddr(uchar *addr, char *ip) { if(ipcmp(addr, IPnoaddr) == 0) parseip(addr, ip); } static void setipmask(uchar *mask, char *ip) { if(ipcmp(mask, IPnoaddr) == 0) parseipmask(mask, ip); } /* * do an ipinfo with defaults */ int lookupip(uchar *ipaddr, Info *iip, int gate) { char ip[32]; Ndbtuple *t, *nt; char *attrs[32], **p; if(opendb() == nil){ warning(1, "can't open db"); return -1; } p = attrs; *p++ = "ip"; *p++ = "ipmask"; *p++ = "@ipgw"; if(!gate){ *p++ = "bootf"; *p++ = "bootf2"; *p++ = "@tftp"; *p++ = "@tftp2"; *p++ = "rootpath"; *p++ = "dhcp"; *p++ = "vendorclass"; *p++ = "ether"; *p++ = "dom"; *p++ = "@fs"; *p++ = "@auth"; } *p = 0; memset(iip, 0, sizeof(*iip)); snprint(ip, sizeof(ip), "%I", ipaddr); t = ndbipinfo(db, "ip", ip, attrs, p - attrs); if(t == nil) return -1; for(nt = t; nt != nil; nt = nt->entry){ if(strcmp(nt->attr, "ip") == 0) setipaddr(iip->ipaddr, nt->val); else if(strcmp(nt->attr, "ipmask") == 0) setipmask(iip->ipmask, nt->val); else if(strcmp(nt->attr, "fs") == 0) setipaddr(iip->fsip, nt->val); else if(strcmp(nt->attr, "auth") == 0) setipaddr(iip->auip, nt->val); else if(strcmp(nt->attr, "tftp") == 0) setipaddr(iip->tftp, nt->val); else if(strcmp(nt->attr, "tftp2") == 0) setipaddr(iip->tftp2, nt->val); else if(strcmp(nt->attr, "ipgw") == 0) setipaddr(iip->gwip, nt->val); else if(strcmp(nt->attr, "ether") == 0){ /* * this is probably wrong for machines with multiple * ethers. bootp or dhcp requests could come from any * of the ethers listed in the ndb entry. */ if(memcmp(iip->etheraddr, noetheraddr, 6) == 0) parseether(iip->etheraddr, nt->val); iip->indb = 1; } else if(strcmp(nt->attr, "dhcp") == 0){ if(iip->dhcpgroup[0] == 0) strcpy(iip->dhcpgroup, nt->val); } else if(strcmp(nt->attr, "bootf") == 0){ if(iip->bootf[0] == 0) strcpy(iip->bootf, nt->val); } else if(strcmp(nt->attr, "bootf2") == 0){ if(iip->bootf2[0] == 0) strcpy(iip->bootf2, nt->val); } else if(strcmp(nt->attr, "vendor") == 0){ if(iip->vendor[0] == 0) strcpy(iip->vendor, nt->val); } else if(strcmp(nt->attr, "dom") == 0){ if(iip->domain[0] == 0) strcpy(iip->domain, nt->val); } else if(strcmp(nt->attr, "rootpath") == 0){ if(iip->rootpath[0] == 0) strcpy(iip->rootpath, nt->val); } } ndbfree(t); maskip(iip->ipaddr, iip->ipmask, iip->ipnet); return 0; } static uchar zeroes[6]; /* * lookup info about a client in the database. Find an address on the * same net as riip. */ int lookup(Bootp *bp, Info *iip, Info *riip) { Ndbtuple *t, *nt; Ndbs s; char *hwattr; char *hwval, hwbuf[33]; uchar ciaddr[IPaddrlen]; if(opendb() == nil){ warning(1, "can't open db"); return -1; } memset(iip, 0, sizeof(*iip)); /* client knows its address? */ v4tov6(ciaddr, bp->ciaddr); if(validip(ciaddr)){ if(lookupip(ciaddr, iip, 0) < 0) { if (debug) warning(0, "don't know %I", ciaddr); return -1; /* don't know anything about it */ } if(!samenet(riip->ipaddr, iip)){ warning(0, "%I not on %I", ciaddr, riip->ipnet); return -1; } /* * see if this is a masquerade, i.e., if the ether * address doesn't match what we expected it to be. */ if(memcmp(iip->etheraddr, zeroes, 6) != 0) if(memcmp(bp->chaddr, iip->etheraddr, 6) != 0) warning(0, "ciaddr %I rcvd from %E instead of %E", ciaddr, bp->chaddr, iip->etheraddr); return 0; } if(bp->hlen > Maxhwlen) return -1; switch(bp->htype){ case 1: hwattr = "ether"; hwval = hwbuf; snprint(hwbuf, sizeof(hwbuf), "%E", bp->chaddr); break; default: syslog(0, blog, "not ethernet %E, htype %d, hlen %d", bp->chaddr, bp->htype, bp->hlen); return -1; } /* * use hardware address to find an ip address on * same net as riip */ t = ndbsearch(db, &s, hwattr, hwval); while(t){ for(nt = t; nt; nt = nt->entry){ if(strcmp(nt->attr, "ip") != 0) continue; parseip(ciaddr, nt->val); if(lookupip(ciaddr, iip, 0) < 0) continue; if(samenet(riip->ipaddr, iip)){ ndbfree(t); return 0; } } ndbfree(t); t = ndbsnext(&s, hwattr, hwval); } return -1; } /* * interface to ndbipinfo */ Ndbtuple* lookupinfo(uchar *ipaddr, char **attr, int n) { char ip[32]; sprint(ip, "%I", ipaddr); return ndbipinfo(db, "ip", ip, attr, n); } /* * return the ip addresses for a type of server for system ip */ int lookupserver(char *attr, uchar **ipaddrs, Ndbtuple *t) { Ndbtuple *nt; int rv = 0; for(nt = t; rv < 2 && nt != nil; nt = nt->entry) if(strcmp(nt->attr, attr) == 0){ parseip(ipaddrs[rv], nt->val); rv++; } return rv; } /* * just lookup the name */ void lookupname(char *val, Ndbtuple *t) { Ndbtuple *nt; for(nt = t; nt != nil; nt = nt->entry) if(strcmp(nt->attr, "dom") == 0){ strcpy(val, nt->val); break; } }