ref: bdc1b187c45dbaeaa7dadce4d7999d9d550ec78f
dir: /sys/src/cmd/ndb/dblookup.c/
#include <u.h> #include <libc.h> #include <bio.h> #include <ndb.h> #include <ip.h> #include <ctype.h> #include "dns.h" enum { Nibwidth = 4, Nibmask = (1<<Nibwidth) - 1, V6maxrevdomdepth = 128 / Nibwidth, /* bits / bits-per-nibble */ /* * ttl for generated ptr records. it was zero, which might seem * like a good idea, but some dns implementations seem to be * confused by a zero ttl, and instead of using the data and then * discarding the RR, they conclude that they don't have valid data. */ Ptrttl = 2*Min, }; static Ndb *db; static Lock dblock; static RR* addrrr(Ndbtuple*, Ndbtuple*); static RR* cnamerr(Ndbtuple*, Ndbtuple*); static void createptrs(void); static RR* dblookup1(char*, int, int, int); static RR* doaxfr(Ndb*, char*); static Ndbtuple*look(Ndbtuple*, Ndbtuple*, char*); static RR* mxrr(Ndbtuple*, Ndbtuple*); static RR* nsrr(Ndbtuple*, Ndbtuple*); static RR* nullrr(Ndbtuple*, Ndbtuple*); static RR* ptrrr(Ndbtuple*, Ndbtuple*); static RR* soarr(Ndbtuple*, Ndbtuple*); static RR* srvrr(Ndbtuple*, Ndbtuple*); static RR* txtrr(Ndbtuple*, Ndbtuple*); static int implemented[Tall] = { [Ta] 1, [Taaaa] 1, [Tcname] 1, [Tmx] 1, [Tns] 1, [Tnull] 1, [Tptr] 1, [Tsoa] 1, [Tsrv] 1, [Ttxt] 1, }; /* straddle server configuration */ static Ndbtuple *indoms, *innmsrvs, *outnmsrvs; static void nstrcpy(char *to, char *from, int len) { strncpy(to, from, len); to[len-1] = 0; } int opendatabase(void) { char netdbnm[256]; Ndb *xdb, *netdb; if (db) return 0; xdb = ndbopen(dbfile); /* /lib/ndb */ snprint(netdbnm, sizeof netdbnm, "%s/ndb", mntpt); for(netdb = xdb; netdb; netdb = netdb->next) if(strcmp(netdb->file, netdbnm) == 0){ db = xdb; return 0; } netdb = ndbopen(netdbnm); /* /net/ndb */ if(netdb) netdb->nohash = 1; db = ndbcat(netdb, xdb); /* both */ return db? 0: -1; } /* * lookup an RR in the network database, look for matches * against both the domain name and the wildcarded domain name. * * the lock makes sure only one process can be accessing the data * base at a time. This is important since there's a lot of * shared state there. * * e.g. for x.research.bell-labs.com, first look for a match against * the x.research.bell-labs.com. If nothing matches, * try *.research.bell-labs.com. */ RR* dblookup(char *name, int class, int type, int auth, int ttl) { int err; char buf[Domlen], *wild; RR *rp, *tp; DN *dp, *ndp; /* so far only internet lookups are implemented */ if(class != Cin) return 0; err = Rname; rp = nil; if(type == Tall){ for (type = Ta; type < Tall; type++) if(implemented[type]) rrcat(&rp, dblookup(name, class, type, auth, ttl)); return rp; } lock(&dblock); dp = idnlookup(name, class, 1); if(opendatabase() < 0) goto out; if(dp->rr) err = 0; /* first try the given name */ if(cfg.cachedb) rp = rrlookup(dp, type, NOneg); else rp = dblookup1(name, type, auth, ttl); if(rp) goto out; /* walk the domain name trying the wildcard '*' at each position */ for(wild = strchr(name, '.'); wild; wild = strchr(wild+1, '.')){ snprint(buf, sizeof buf, "*%s", wild); ndp = idnlookup(buf, class, 1); if(ndp->rr) err = 0; if(cfg.cachedb) rp = rrlookup(ndp, type, NOneg); else rp = dblookup1(buf, type, auth, ttl); if(rp) break; } out: /* add owner to uncached records */ if(rp) for(tp = rp; tp; tp = tp->next) tp->owner = dp; else { /* * don't call it non-existent if it's not ours * (unless we're a resolver). */ if(err == Rname && (!inmyarea(dp->name) || cfg.resolver)) err = Rserver; dp->respcode = err; } unlock(&dblock); return rp; } static ulong intval(Ndbtuple *entry, Ndbtuple *pair, char *attr, ulong def) { Ndbtuple *t = look(entry, pair, attr); return (t? strtoul(t->val, 0, 10): def); } static void mklowcase(char *cp) { Rune r; while(*cp != 0){ chartorune(&r, cp); r = tolowerrune(r); cp += runetochar(cp, &r); } } /* * lookup an RR in the network database */ static RR* dblookup1(char *name, int type, int auth, int ttl) { Ndbtuple *t, *nt; RR *rp, *list, **l; Ndbs s; char dname[Domlen]; char *attr; DN *dp; RR *(*f)(Ndbtuple*, Ndbtuple*); int found, x; dp = nil; switch(type){ case Tptr: attr = "ptr"; f = ptrrr; break; case Ta: attr = "ip"; f = addrrr; break; case Taaaa: attr = "ipv6"; f = addrrr; break; case Tnull: attr = "nullrr"; f = nullrr; break; case Tns: attr = "ns"; f = nsrr; break; case Tsoa: attr = "soa"; f = soarr; break; case Tsrv: attr = "srv"; f = srvrr; break; case Tmx: attr = "mx"; f = mxrr; break; case Tcname: attr = "cname"; f = cnamerr; break; case Taxfr: case Tixfr: return doaxfr(db, name); default: // dnslog("dblookup1(%s) bad type", name); return nil; } /* * find a matching entry in the database */ nstrcpy(dname, name, sizeof dname); for(x=0; x<4; x++){ switch(x){ case 1: /* try unicode */ if(idn2utf(name, dname, sizeof dname) == nil){ nstrcpy(dname, name, sizeof dname); continue; } if(strcmp(name, dname) == 0) continue; break; case 3: /* try ascii (lower case) */ if(utf2idn(name, dname, sizeof dname) == nil) continue; case 2: mklowcase(dname); if(strcmp(name, dname) == 0) continue; break; } t = nil; free(ndbgetvalue(db, &s, "dom", dname, attr, &t)); if(t == nil && strchr(dname, '.') == nil) free(ndbgetvalue(db, &s, "sys", dname, attr, &t)); if(t != nil) break; } if(t == nil) { // dnslog("dblookup1(%s) name not found", name); return nil; } /* search whole entry for default domain name */ for(nt = t; nt; nt = nt->entry) if(strcmp(nt->attr, "dom") == 0){ nstrcpy(dname, nt->val, sizeof dname); break; } /* ttl is maximum of soa minttl and entry's ttl ala rfc883 */ x = intval(t, s.t, "ttl", 0); if(x > ttl) ttl = x; /* default ttl is one day */ if(ttl < 0) ttl = DEFTTL; /* * The database has 2 levels of precedence; line and entry. * Pairs on the same line bind tighter than pairs in the * same entry, so we search the line first. */ found = 0; list = 0; l = &list; for(nt = s.t;; ){ if(found == 0 && strcmp(nt->attr, "dom") == 0){ nstrcpy(dname, nt->val, sizeof dname); found = 1; } if(strcmp(attr, nt->attr) == 0){ rp = (*f)(t, nt); rp->auth = auth; rp->db = 1; if(ttl) rp->ttl = ttl; if(dp == nil) dp = idnlookup(dname, Cin, 1); rp->owner = dp; *l = rp; l = &rp->next; nt->ptr = 1; } nt = nt->line; if(nt == s.t) break; } /* search whole entry */ for(nt = t; nt; nt = nt->entry) if(nt->ptr == 0 && strcmp(attr, nt->attr) == 0){ rp = (*f)(t, nt); rp->db = 1; if(ttl) rp->ttl = ttl; rp->auth = auth; if(dp == nil) dp = idnlookup(dname, Cin, 1); rp->owner = dp; *l = rp; l = &rp->next; } ndbfree(t); // dnslog("dblookup1(%s) -> %#p", name, list); return list; } /* * make various types of resource records from a database entry */ static RR* addrrr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; uchar addr[IPaddrlen]; USED(entry); parseip(addr, pair->val); if(isv4(addr)) rp = rralloc(Ta); else rp = rralloc(Taaaa); rp->ip = dnlookup(pair->val, Cin, 1); return rp; } static RR* nullrr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; USED(entry); rp = rralloc(Tnull); rp->null->data = (uchar*)estrdup(pair->val); rp->null->dlen = strlen((char*)rp->null->data); return rp; } /* * txt rr strings are at most 255 bytes long. one * can represent longer strings by multiple concatenated * <= 255 byte ones. */ static RR* txtrr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; Txt *t, **l; int i, len, sofar; USED(entry); rp = rralloc(Ttxt); l = &rp->txt; rp->txt = nil; len = strlen(pair->val); sofar = 0; while(len > sofar){ t = emalloc(sizeof(*t)); t->next = nil; i = len-sofar; if(i > 255) i = 255; t->p = emalloc(i+1); memmove(t->p, pair->val+sofar, i); t->p[i] = 0; sofar += i; *l = t; l = &t->next; } return rp; } static RR* cnamerr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; USED(entry); rp = rralloc(Tcname); rp->host = idnlookup(pair->val, Cin, 1); return rp; } static RR* mxrr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; rp = rralloc(Tmx); rp->host = idnlookup(pair->val, Cin, 1); rp->pref = intval(entry, pair, "pref", 1); return rp; } static RR* nsrr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; Ndbtuple *t; rp = rralloc(Tns); rp->host = idnlookup(pair->val, Cin, 1); t = look(entry, pair, "soa"); if(t && t->val[0] == 0) rp->local = 1; return rp; } static RR* ptrrr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; USED(entry); rp = rralloc(Tns); rp->ptr = dnlookup(pair->val, Cin, 1); return rp; } static RR* soarr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; Ndbtuple *ns, *mb, *t; char mailbox[Domlen]; Ndb *ndb; char *p; rp = rralloc(Tsoa); rp->soa->serial = 1; for(ndb = db; ndb; ndb = ndb->next) if(ndb->mtime > rp->soa->serial) rp->soa->serial = ndb->mtime; rp->soa->retry = intval(entry, pair, "retry", Hour); rp->soa->expire = intval(entry, pair, "expire", Day); rp->soa->minttl = intval(entry, pair, "ttl", Day); rp->soa->refresh = intval(entry, pair, "refresh", Day); rp->soa->serial = intval(entry, pair, "serial", rp->soa->serial); ns = look(entry, pair, "ns"); if(ns == nil) ns = look(entry, pair, "dom"); rp->host = idnlookup(ns->val, Cin, 1); /* accept all of: * mbox=person * [email protected] * mbox=person.machine.dom */ mb = look(entry, pair, "mbox"); if(mb == nil) mb = look(entry, pair, "mb"); if(mb) if(strchr(mb->val, '.')) { p = strchr(mb->val, '@'); if(p != nil) *p = '.'; rp->rmb = idnlookup(mb->val, Cin, 1); } else { snprint(mailbox, sizeof mailbox, "%s.%s", mb->val, ns->val); rp->rmb = idnlookup(mailbox, Cin, 1); } else { snprint(mailbox, sizeof mailbox, "postmaster.%s", ns->val); rp->rmb = idnlookup(mailbox, Cin, 1); } /* * hang dns slaves off of the soa. this is * for managing the area. */ for(t = entry; t != nil; t = t->entry) if(strcmp(t->attr, "dnsslave") == 0) addserver(&rp->soa->slaves, t->val); return rp; } static RR* srvrr(Ndbtuple *entry, Ndbtuple *pair) { RR *rp; rp = rralloc(Tsrv); rp->host = idnlookup(pair->val, Cin, 1); rp->srv->pri = intval(entry, pair, "pri", 0); rp->srv->weight = intval(entry, pair, "weight", 0); /* TODO: translate service name to port # */ rp->port = intval(entry, pair, "port", 0); return rp; } /* * Look for a pair with the given attribute. look first on the same line, * then in the whole entry. */ static Ndbtuple* look(Ndbtuple *entry, Ndbtuple *line, char *attr) { Ndbtuple *nt; /* first look on same line (closer binding) */ for(nt = line;;){ if(strcmp(attr, nt->attr) == 0) return nt; nt = nt->line; if(nt == line) break; } /* search whole tuple */ for(nt = entry; nt; nt = nt->entry) if(strcmp(attr, nt->attr) == 0) return nt; return 0; } /* these are answered specially by the tcp version */ static RR* doaxfr(Ndb *db, char *name) { USED(db, name); return 0; } /* * read the database into the cache */ static void dbpair2cache(DN *dp, Ndbtuple *entry, Ndbtuple *pair) { RR *rp; static ulong ord; rp = 0; if(strcmp(pair->attr, "ip") == 0 || strcmp(pair->attr, "ipv6") == 0) { dp->ordinal = ord++; rp = addrrr(entry, pair); } else if(strcmp(pair->attr, "ns") == 0) rp = nsrr(entry, pair); else if(strcmp(pair->attr, "soa") == 0) { rp = soarr(entry, pair); addarea(dp, rp, pair); } else if(strcmp(pair->attr, "mx") == 0) rp = mxrr(entry, pair); else if(strcmp(pair->attr, "srv") == 0) rp = srvrr(entry, pair); else if(strcmp(pair->attr, "cname") == 0) rp = cnamerr(entry, pair); else if(strcmp(pair->attr, "nullrr") == 0) rp = nullrr(entry, pair); else if(strcmp(pair->attr, "txtrr") == 0) rp = txtrr(entry, pair); if(rp == nil) return; rp->owner = dp; rp->db = 1; rp->ttl = intval(entry, pair, "ttl", rp->ttl); rrattach(rp, Notauthoritative); dnagenever(dp); } static void dbtuple2cache(Ndbtuple *t) { Ndbtuple *et, *nt; DN *dp; for(et = t; et; et = et->entry) if(strcmp(et->attr, "dom") == 0){ dp = idnlookup(et->val, Cin, 1); /* first same line */ for(nt = et->line; nt != et; nt = nt->line){ dbpair2cache(dp, t, nt); nt->ptr = 1; } /* then rest of entry */ for(nt = t; nt; nt = nt->entry){ if(nt->ptr == 0) dbpair2cache(dp, t, nt); nt->ptr = 0; } } } static void dbfile2cache(Ndb *db) { Ndbtuple *t; if(debug) dnslog("rereading %s", db->file); Bseek(&db->b, 0, 0); while(t = ndbparse(db)){ dbtuple2cache(t); ndbfree(t); } } /* called with dblock held */ static void loaddomsrvs(void) { Ndbs s; if (!cfg.inside || !cfg.straddle || !cfg.serve) return; if (indoms) { ndbfree(indoms); ndbfree(innmsrvs); ndbfree(outnmsrvs); indoms = innmsrvs = outnmsrvs = nil; } if (db == nil) opendatabase(); free(ndbgetvalue(db, &s, "sys", "inside-dom", "dom", &indoms)); free(ndbgetvalue(db, &s, "sys", "inside-ns", "ip", &innmsrvs)); free(ndbgetvalue(db, &s, "sys", "outside-ns", "ip", &outnmsrvs)); dnslog("[%d] ndb changed: reloaded inside-dom, inside-ns, outside-ns", getpid()); } void db2cache(int doit) { ulong youngest; Ndb *ndb; Dir *d; static ulong lastcheck, lastyoungest; /* no faster than once every 2 minutes */ if(now < lastcheck + 2*Min && !doit) return; refresh_areas(owned); lock(&dblock); if(opendatabase() < 0){ unlock(&dblock); return; } /* * file may be changing as we are reading it, so loop till * mod times are consistent. * * we don't use the times in the ndb records because they may * change outside of refreshing our cached knowledge. */ for(;;){ lastcheck = now; youngest = 0; for(ndb = db; ndb; ndb = ndb->next) /* dirfstat avoids walking the mount table each time */ if((d = dirfstat(Bfildes(&ndb->b))) != nil || (d = dirstat(ndb->file)) != nil){ if(d->mtime > youngest) youngest = d->mtime; free(d); } if(!doit && youngest == lastyoungest) break; /* forget our area definition */ freearea(&owned); freearea(&delegated); /* reopen all the files (to get oldest for time stamp) */ for(ndb = db; ndb; ndb = ndb->next) ndbreopen(ndb); /* reload straddle-server configuration */ loaddomsrvs(); /* mark all db records as timed out */ dnagedb(); if(cfg.cachedb){ /* read in new entries */ for(ndb = db; ndb; ndb = ndb->next) dbfile2cache(ndb); } /* * mark as authoritative anything in our domain, * delete timed out db records */ dnauthdb(); /* remove old entries */ dnageall(1); doit = 0; lastyoungest = youngest; createptrs(); } unlock(&dblock); } extern char mntpt[Maxpath]; /* net mountpoint */ static uchar ipaddr[IPaddrlen]; /* my ip address */ /* * get all my xxx * caller ndbfrees the result */ Ndbtuple* lookupinfo(char *attr) { char buf[64]; char *a[2]; Ndbtuple *t; if(ipcmp(ipaddr, IPnoaddr) == 0) if(myipaddr(ipaddr, mntpt) < 0) return nil; snprint(buf, sizeof buf, "%I", ipaddr); a[0] = attr; lock(&dblock); if(opendatabase() < 0){ unlock(&dblock); return nil; } t = ndbipinfo(db, "ip", buf, a, 1); unlock(&dblock); return t; } /* * return non-zero if this is a bad delegation */ int baddelegation(RR *rp, RR *nsrp, uchar *addr) { static int whined; static Ndbtuple *t; Ndbtuple *nt; if(rp->type != Tns) return 0; if(t == nil) t = lookupinfo("dom"); if(t != nil){ /* see if delegating to us what we don't own */ for(nt = t; nt != nil; nt = nt->entry) if(rp->host && cistrcmp(rp->host->name, nt->val) == 0) break; if(nt != nil && !inmyarea(rp->owner->name)){ if (!whined) { whined = 1; dnslog("bad delegation %R from %I/%s; " "no further logging of them", rp, addr, nsrp->host->name); } return 1; } } return 0; } int myaddr(char *addr) { char *line, *sp; char buf[64]; Biobuf *bp; if(ipcmp(ipaddr, IPnoaddr) == 0) if(myipaddr(ipaddr, mntpt) < 0) return -1; snprint(buf, sizeof buf, "%I", ipaddr); if (strcmp(addr, buf) == 0) { dnslog("rejecting my ip %s as local dns server", addr); return 1; } snprint(buf, sizeof buf, "%s/ipselftab", mntpt); bp = Bopen(buf, OREAD); if (bp != nil) { while ((line = Brdline(bp, '\n')) != nil) { line[Blinelen(bp) - 1] = '\0'; sp = strchr(line, ' '); if (sp) { *sp = '\0'; if (strcmp(addr, line) == 0) { dnslog("rejecting my ip %s as local dns server", addr); return 1; } } } Bterm(bp); } return 0; } static char *locdns[20]; static QLock locdnslck; static void addlocaldnsserver(DN *dp, int class, char *ipaddr, int i) { int n; DN *nsdp; RR *rp; char buf[32]; uchar ip[IPaddrlen]; /* reject our own ip addresses so we don't query ourselves via udp */ if (myaddr(ipaddr)) return; qlock(&locdnslck); for (n = 0; n < i && n < nelem(locdns) && locdns[n]; n++) if (strcmp(locdns[n], ipaddr) == 0) { dnslog("rejecting duplicate local dns server ip %s", ipaddr); qunlock(&locdnslck); return; } if (n < nelem(locdns)) if (locdns[n] == nil || ++n < nelem(locdns)) locdns[n] = strdup(ipaddr); /* remember 1st few local ns */ qunlock(&locdnslck); /* ns record for name server, make up an impossible name */ rp = rralloc(Tns); snprint(buf, sizeof buf, "local#dns#server%d", i); nsdp = dnlookup(buf, class, 1); rp->host = nsdp; rp->owner = dp; /* e.g., local#dns#servers */ rp->local = 1; rp->db = 1; rp->ttl = 10*Min; rrattach(rp, Authoritative); /* will not attach rrs in my area */ dnagenever(dp); /* A or AAAA record */ if (parseip(ip, ipaddr) >= 0 && isv4(ip)) rp = rralloc(Ta); else rp = rralloc(Taaaa); rp->ip = dnlookup(ipaddr, class, 1); rp->owner = nsdp; rp->local = 1; rp->db = 1; rp->ttl = 10*Min; rrattach(rp, Authoritative); /* will not attach rrs in my area */ dnagenever(nsdp); dnslog("added local dns server %s at %s", buf, ipaddr); } /* * return list of dns server addresses to use when * acting just as a resolver. */ RR* dnsservers(int class) { int i, n; char *p; char *args[5]; Ndbtuple *t, *nt; RR *nsrp; DN *dp; dp = dnlookup("local#dns#servers", class, 1); nsrp = rrlookup(dp, Tns, NOneg); if(nsrp != nil) return nsrp; p = getenv("DNSSERVER"); /* list of ip addresses */ if(p != nil){ n = tokenize(p, args, nelem(args)); for(i = 0; i < n; i++) addlocaldnsserver(dp, class, args[i], i); free(p); } else { t = lookupinfo("@dns"); /* @dns=ip1 @dns=ip2 ... */ if(t == nil) return nil; i = 0; for(nt = t; nt != nil; nt = nt->entry){ addlocaldnsserver(dp, class, nt->val, i); i++; } ndbfree(t); } return rrlookup(dp, Tns, NOneg); } static void addlocaldnsdomain(DN *dp, int class, char *domain) { RR *rp; /* ptr record */ rp = rralloc(Tptr); rp->ptr = dnlookup(domain, class, 1); rp->owner = dp; rp->db = 1; rp->ttl = 10*Min; rrattach(rp, Authoritative); dnagenever(dp); } /* * return list of domains to use when resolving names without '.'s */ RR* domainlist(int class) { Ndbtuple *t, *nt; RR *rp; DN *dp; dp = dnlookup("local#dns#domains", class, 1); rp = rrlookup(dp, Tptr, NOneg); if(rp != nil) return rp; t = lookupinfo("dnsdomain"); if(t == nil) return nil; for(nt = t; nt != nil; nt = nt->entry) addlocaldnsdomain(dp, class, nt->val); ndbfree(t); return rrlookup(dp, Tptr, NOneg); } char *v4ptrdom = ".in-addr.arpa"; char *v6ptrdom = ".ip6.arpa"; /* ip6.int deprecated, rfc 3152 */ char *attribs[] = { "ipmask", 0 }; /* * create ptrs that are in our v4 areas */ static void createv4ptrs(void) { int len, dlen, n; char *dom; char buf[Domlen], ipa[48]; char *f[40]; uchar net[IPaddrlen], mask[IPaddrlen]; Area *s; Ndbtuple *t, *nt; dlen = strlen(v4ptrdom); for(s = owned; s; s = s->next){ dom = s->soarr->owner->name; len = strlen(dom); if((len <= dlen || cistrcmp(dom+len-dlen, v4ptrdom) != 0) && cistrcmp(dom, v4ptrdom+1) != 0) continue; /* get mask and net value */ nstrcpy(buf, dom, sizeof buf); /* buf contains something like 178.204.in-addr.arpa (n==4) */ n = getfields(buf, f, nelem(f), 0, "."); memset(mask, 0xff, IPaddrlen); ipmove(net, v4prefix); switch(n){ case 3: /* /8 */ net[IPv4off] = atoi(f[0]); mask[IPv4off+1] = 0; mask[IPv4off+2] = 0; mask[IPv4off+3] = 0; break; case 4: /* /16 */ net[IPv4off] = atoi(f[1]); net[IPv4off+1] = atoi(f[0]); mask[IPv4off+2] = 0; mask[IPv4off+3] = 0; break; case 5: /* /24 */ net[IPv4off] = atoi(f[2]); net[IPv4off+1] = atoi(f[1]); net[IPv4off+2] = atoi(f[0]); mask[IPv4off+3] = 0; break; case 6: /* rfc2317: classless in-addr.arpa delegation */ net[IPv4off] = atoi(f[3]); net[IPv4off+1] = atoi(f[2]); net[IPv4off+2] = atoi(f[1]); net[IPv4off+3] = atoi(f[0]); sprint(ipa, "%I", net); t = ndbipinfo(db, "ip", ipa, attribs, 1); if(t == nil) /* could be a reverse with no forward */ continue; nt = look(t, t, "ipmask"); if(nt == nil){ /* we're confused */ ndbfree(t); continue; } parseipmask(mask, nt->val); ndbfree(t); n = 5; break; default: continue; } /* * go through all domain entries looking for RR's * in this network and create ptrs. * +2 for ".in-addr.arpa". */ dnptr(net, mask, dom, Ta, 4+2-n, Ptrttl); } } /* convert bytes to nibbles, big-endian */ void bytes2nibbles(uchar *nibbles, uchar *bytes, int nbytes) { while (nbytes-- > 0) { *nibbles++ = *bytes >> Nibwidth; *nibbles++ = *bytes++ & Nibmask; } } void nibbles2bytes(uchar *bytes, uchar *nibbles, int nnibs) { for (; nnibs >= 2; nnibs -= 2) { *bytes++ = nibbles[0] << Nibwidth | (nibbles[1]&Nibmask); nibbles += 2; } if (nnibs > 0) *bytes = nibbles[0] << Nibwidth; } /* * create ptrs that are in our v6 areas. see rfc3596 */ static void createv6ptrs(void) { int len, dlen, i, n, pfxnibs; char *dom; char buf[Domlen]; char *f[40]; uchar net[IPaddrlen], mask[IPaddrlen]; uchar nibnet[IPaddrlen*2], nibmask[IPaddrlen*2]; Area *s; dlen = strlen(v6ptrdom); for(s = owned; s; s = s->next){ dom = s->soarr->owner->name; len = strlen(dom); if((len <= dlen || cistrcmp(dom+len-dlen, v6ptrdom) != 0) && cistrcmp(dom, v6ptrdom+1) != 0) continue; /* get mask and net value */ nstrcpy(buf, dom, sizeof buf); /* buf contains something like 2.0.0.2.ip6.arpa (n==6) */ n = getfields(buf, f, nelem(f), 0, "."); pfxnibs = n - 2; /* 2 for .ip6.arpa */ if (pfxnibs < 0 || pfxnibs > V6maxrevdomdepth) continue; memset(net, 0, IPaddrlen); memset(mask, 0xff, IPaddrlen); bytes2nibbles(nibnet, net, IPaddrlen); bytes2nibbles(nibmask, mask, IPaddrlen); /* copy prefix of f, in reverse order, to start of net. */ for (i = 0; i < pfxnibs; i++) nibnet[i] = strtol(f[pfxnibs - 1 - i], nil, 16); /* zero nibbles of mask after prefix in net */ memset(nibmask + pfxnibs, 0, V6maxrevdomdepth - pfxnibs); nibbles2bytes(net, nibnet, 2*IPaddrlen); nibbles2bytes(mask, nibmask, 2*IPaddrlen); /* * go through all domain entries looking for RR's * in this network and create ptrs. */ dnptr(net, mask, dom, Taaaa, V6maxrevdomdepth - pfxnibs, Ptrttl); } } /* * create ptrs that are in our areas */ static void createptrs(void) { createv4ptrs(); createv6ptrs(); } /* * is this domain (or DOMAIN or Domain or dOMAIN) * internal to our organisation (behind our firewall)? * only inside straddling servers care, everybody else gets told `yes', * so they'll use mntpt for their queries. */ int insideaddr(char *dom) { int domlen, vallen, rv; Ndbtuple *t; if (!cfg.inside || !cfg.straddle || !cfg.serve) return 1; if (dom[0] == '\0' || strcmp(dom, ".") == 0) /* dns root? */ return 1; /* hack for initialisation */ lock(&dblock); if (indoms == nil) loaddomsrvs(); if (indoms == nil) { unlock(&dblock); return 1; /* no "inside-dom" sys, try inside nameservers */ } rv = 0; domlen = strlen(dom); for (t = indoms; t != nil; t = t->entry) { if (strcmp(t->attr, "dom") != 0) continue; vallen = strlen(t->val); if (cistrcmp(dom, t->val) == 0 || domlen > vallen && cistrcmp(dom + domlen - vallen, t->val) == 0 && dom[domlen - vallen - 1] == '.') { rv = 1; break; } } unlock(&dblock); return rv; } int insidens(uchar *ip) { uchar ipa[IPaddrlen]; Ndbtuple *t; for (t = innmsrvs; t != nil; t = t->entry) if (strcmp(t->attr, "ip") == 0) { parseip(ipa, t->val); if (memcmp(ipa, ip, sizeof ipa) == 0) return 1; } return 0; } int outsidensip(int n, uchar *ip) { int i; Ndbtuple *t; i = 0; for (t = outnmsrvs; t != nil; t = t->entry) if (strcmp(t->attr, "ip") == 0 && i++ == n) { parseip(ip, t->val); return 0; } return -1; }