1 3e0d8fb3 2005-12-27 devnull #include <u.h>
2 3e0d8fb3 2005-12-27 devnull #include <libc.h>
3 3e0d8fb3 2005-12-27 devnull #include <ip.h>
4 3e0d8fb3 2005-12-27 devnull #include <bio.h>
5 3e0d8fb3 2005-12-27 devnull #include <ndb.h>
6 3e0d8fb3 2005-12-27 devnull #include "dns.h"
8 3e0d8fb3 2005-12-27 devnull static RR* doextquery(DNSmsg*, Request*, int);
9 3e0d8fb3 2005-12-27 devnull static void hint(RR**, RR*);
11 3e0d8fb3 2005-12-27 devnull extern char *logfile;
14 3e0d8fb3 2005-12-27 devnull * answer a dns request
17 3e0d8fb3 2005-12-27 devnull dnserver(DNSmsg *reqp, DNSmsg *repp, Request *req)
19 3e0d8fb3 2005-12-27 devnull RR *tp, *neg;
20 3e0d8fb3 2005-12-27 devnull char *cp;
21 3e0d8fb3 2005-12-27 devnull DN *nsdp, *dp;
22 3e0d8fb3 2005-12-27 devnull Area *myarea;
23 3e0d8fb3 2005-12-27 devnull char tname[32];
25 3e0d8fb3 2005-12-27 devnull dncheck(nil, 1);
27 3e0d8fb3 2005-12-27 devnull memset(repp, 0, sizeof(*repp));
28 3e0d8fb3 2005-12-27 devnull repp->id = reqp->id;
29 3e0d8fb3 2005-12-27 devnull repp->flags = Fresp | Fcanrec | Oquery;
31 3e0d8fb3 2005-12-27 devnull /* move one question from reqp to repp */
32 3e0d8fb3 2005-12-27 devnull tp = reqp->qd;
33 3e0d8fb3 2005-12-27 devnull reqp->qd = tp->next;
34 3e0d8fb3 2005-12-27 devnull tp->next = 0;
35 3e0d8fb3 2005-12-27 devnull repp->qd = tp;
37 3e0d8fb3 2005-12-27 devnull if(!rrsupported(repp->qd->type)){
38 3e0d8fb3 2005-12-27 devnull syslog(0, logfile, "server: request %s", rrname(repp->qd->type, tname, sizeof tname));
39 3e0d8fb3 2005-12-27 devnull repp->flags = Runimplimented | Fresp | Fcanrec | Oquery;
43 3e0d8fb3 2005-12-27 devnull if(repp->qd->owner->class != Cin){
44 3e0d8fb3 2005-12-27 devnull syslog(0, logfile, "server: class %d", repp->qd->owner->class);
45 3e0d8fb3 2005-12-27 devnull repp->flags = Runimplimented | Fresp | Fcanrec | Oquery;
49 3e0d8fb3 2005-12-27 devnull myarea = inmyarea(repp->qd->owner->name);
50 3e0d8fb3 2005-12-27 devnull if(myarea != nil && (repp->qd->type == Tixfr || repp->qd->type == Taxfr)){
51 3e0d8fb3 2005-12-27 devnull syslog(0, logfile, "server: request %s", rrname(repp->qd->type, tname, sizeof tname));
52 3e0d8fb3 2005-12-27 devnull repp->flags = Runimplimented | Fresp | Fcanrec | Oquery;
57 3e0d8fb3 2005-12-27 devnull * get the answer if we can
59 3e0d8fb3 2005-12-27 devnull if(reqp->flags & Frecurse)
60 3e0d8fb3 2005-12-27 devnull neg = doextquery(repp, req, Recurse);
62 3e0d8fb3 2005-12-27 devnull neg = doextquery(repp, req, Dontrecurse);
64 3e0d8fb3 2005-12-27 devnull /* authority is transitive */
65 3e0d8fb3 2005-12-27 devnull if(myarea != nil || (repp->an && repp->an->auth))
66 3e0d8fb3 2005-12-27 devnull repp->flags |= Fauth;
68 3e0d8fb3 2005-12-27 devnull /* pass on error codes */
69 3e0d8fb3 2005-12-27 devnull if(repp->an == 0){
70 3e0d8fb3 2005-12-27 devnull dp = dnlookup(repp->qd->owner->name, repp->qd->owner->class, 0);
71 3e0d8fb3 2005-12-27 devnull if(dp->rr == 0)
72 3e0d8fb3 2005-12-27 devnull if(reqp->flags & Frecurse)
73 3e0d8fb3 2005-12-27 devnull repp->flags |= dp->nonexistent|Fauth;
76 3e0d8fb3 2005-12-27 devnull if(myarea == nil){
78 3e0d8fb3 2005-12-27 devnull * add name server if we know
80 3e0d8fb3 2005-12-27 devnull for(cp = repp->qd->owner->name; cp; cp = walkup(cp)){
81 3e0d8fb3 2005-12-27 devnull nsdp = dnlookup(cp, repp->qd->owner->class, 0);
82 3e0d8fb3 2005-12-27 devnull if(nsdp == 0)
83 3e0d8fb3 2005-12-27 devnull continue;
85 3e0d8fb3 2005-12-27 devnull repp->ns = rrlookup(nsdp, Tns, OKneg);
86 3e0d8fb3 2005-12-27 devnull if(repp->ns){
87 3e0d8fb3 2005-12-27 devnull /* don't pass on anything we know is wrong */
88 3e0d8fb3 2005-12-27 devnull if(repp->ns->negative){
89 3e0d8fb3 2005-12-27 devnull rrfreelist(repp->ns);
90 3e0d8fb3 2005-12-27 devnull repp->ns = nil;
95 3e0d8fb3 2005-12-27 devnull repp->ns = dblookup(cp, repp->qd->owner->class, Tns, 0, 0);
96 3e0d8fb3 2005-12-27 devnull if(repp->ns)
102 3e0d8fb3 2005-12-27 devnull * add ip addresses as hints
104 3e0d8fb3 2005-12-27 devnull if(repp->qd->type != Taxfr && repp->qd->type != Tixfr){
105 3e0d8fb3 2005-12-27 devnull for(tp = repp->ns; tp; tp = tp->next)
106 3e0d8fb3 2005-12-27 devnull hint(&repp->ar, tp);
107 3e0d8fb3 2005-12-27 devnull for(tp = repp->an; tp; tp = tp->next)
108 3e0d8fb3 2005-12-27 devnull hint(&repp->ar, tp);
112 3e0d8fb3 2005-12-27 devnull * add an soa to the authority section to help client with negative caching
114 3e0d8fb3 2005-12-27 devnull if(repp->an == nil){
115 3e0d8fb3 2005-12-27 devnull if(myarea != nil){
116 3e0d8fb3 2005-12-27 devnull rrcopy(myarea->soarr, &tp);
117 3e0d8fb3 2005-12-27 devnull rrcat(&repp->ns, tp);
118 3e0d8fb3 2005-12-27 devnull } else if(neg != nil) {
119 3e0d8fb3 2005-12-27 devnull if(neg->negsoaowner != nil)
120 3e0d8fb3 2005-12-27 devnull rrcat(&repp->ns, rrlookup(neg->negsoaowner, Tsoa, NOneg));
121 3e0d8fb3 2005-12-27 devnull repp->flags |= neg->negrcode;
126 3e0d8fb3 2005-12-27 devnull * get rid of duplicates
128 3e0d8fb3 2005-12-27 devnull unique(repp->an);
129 3e0d8fb3 2005-12-27 devnull unique(repp->ns);
130 3e0d8fb3 2005-12-27 devnull unique(repp->ar);
132 3e0d8fb3 2005-12-27 devnull rrfreelist(neg);
134 3e0d8fb3 2005-12-27 devnull dncheck(nil, 1);
138 3e0d8fb3 2005-12-27 devnull * satisfy a recursive request. dnlookup will handle cnames.
140 3e0d8fb3 2005-12-27 devnull static RR*
141 3e0d8fb3 2005-12-27 devnull doextquery(DNSmsg *mp, Request *req, int recurse)
143 3e0d8fb3 2005-12-27 devnull int type;
144 3e0d8fb3 2005-12-27 devnull char *name;
145 3e0d8fb3 2005-12-27 devnull RR *rp, *neg;
147 3e0d8fb3 2005-12-27 devnull name = mp->qd->owner->name;
148 3e0d8fb3 2005-12-27 devnull type = mp->qd->type;
149 3e0d8fb3 2005-12-27 devnull rp = dnresolve(name, Cin, type, req, &mp->an, 0, recurse, 1, 0);
151 3e0d8fb3 2005-12-27 devnull /* don't return soa hints as answers, it's wrong */
152 3e0d8fb3 2005-12-27 devnull if(rp && rp->db && !rp->auth && rp->type == Tsoa)
153 3e0d8fb3 2005-12-27 devnull rrfreelist(rp);
155 3e0d8fb3 2005-12-27 devnull /* don't let negative cached entries escape */
156 3e0d8fb3 2005-12-27 devnull neg = rrremneg(&rp);
157 3e0d8fb3 2005-12-27 devnull rrcat(&mp->an, rp);
158 3e0d8fb3 2005-12-27 devnull return neg;
161 3e0d8fb3 2005-12-27 devnull static void
162 3e0d8fb3 2005-12-27 devnull hint(RR **last, RR *rp)
166 3e0d8fb3 2005-12-27 devnull switch(rp->type){
167 3e0d8fb3 2005-12-27 devnull case Tns:
168 3e0d8fb3 2005-12-27 devnull case Tmx:
169 3e0d8fb3 2005-12-27 devnull case Tmb:
170 3e0d8fb3 2005-12-27 devnull case Tmf:
171 3e0d8fb3 2005-12-27 devnull case Tmd:
172 3e0d8fb3 2005-12-27 devnull hp = rrlookup(rp->host, Ta, NOneg);
173 3e0d8fb3 2005-12-27 devnull if(hp == nil)
174 3e0d8fb3 2005-12-27 devnull hp = dblookup(rp->host->name, Cin, Ta, 0, 0);
175 3e0d8fb3 2005-12-27 devnull rrcat(last, hp);