src/types.c: Better record parsing for addr queries.

The parser now needs to know which kind of record it's meant to be
dealing with, so that it can convert it into the right kind of socket
address.  As a result, pap_findaddrs needs to pass in the right record
type when parsing addresses from the additional section, so we separate
out the main work into a separate function.

Signed-off-by: Mark Wooding <mdw@distorted.org.uk>

diff --git a/src/types.c b/src/types.c
index 28db797eb7a7e7a938a8484a28b7ef3391a45c8c..5e3735be4d5073d55810970a38d495430345ae4c 100644 (file)
--- a/src/types.c
+++ b/src/types.c
@@ -24,6 +24,7 @@
  *  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 
  */
 
+#include <stddef.h>
 #include <stdlib.h>
 
 #include <sys/types.h>
@@ -50,7 +51,7 @@
  * _inaddr                    (pa,di,cs
  *                             +search_sortlist, dip_genaddr, csp_genaddr)
  * _in6addr                  (pa,di,cs)
- * _addr                      (pa,di,div,csp,cs,gsz,qs
+ * _addr                      (pap,pa,di,div,csp,cs,gsz,qs
  *                             +search_sortlst_sa, dip_sockaddr,
  *                              addr_rrtypes, icb_addr)
  * _domain                    (pap,csp,cs)
@@ -343,7 +344,7 @@ static adns_status cs_in6addr(vbuf *vb, const void *datap) {
 }
 
 /*
- * _addr   (pa,di,div,csp,cs,gsz,qs
+ * _addr   (pap,pa,di,div,csp,cs,gsz,qs
  *             +search_sortlist_sa, dip_sockaddr, addr_rrtypes, icb_addr)
  */
 
@@ -376,16 +377,42 @@ static unsigned addr_rrtypeflag(adns_rrtype type) {
   return i < addr_nrrtypes ? 1 << i : 0;
 }
 
-static adns_status pa_addr(const parseinfo *pai, int cbyte,
-                          int max, void *datap) {
-  adns_rr_addr *storeto= datap;
+static adns_status pap_addr(const parseinfo *pai, int rrty, size_t rrsz,
+                           int *cbyte_io, int max, adns_rr_addr *storeto) {
   const byte *dgram= pai->dgram;
+  int af, addrlen, salen;
+  const void *oaddr= dgram + *cbyte_io;
+  int avail= max - *cbyte_io;
+  int step= -1;
+  void *addrp= 0;
+
+  switch (rrty) {
+  case adns_r_a:
+    af= AF_INET; addrlen= 4;
+    addrp= &storeto->addr.inet.sin_addr;
+    salen= sizeof(storeto->addr.inet);
+    break;
+  }
+  assert(addrp);
 
-  if (max-cbyte != 4) return adns_s_invaliddata;
-  storeto->len= sizeof(storeto->addr.inet);
-  memset(&storeto->addr,0,sizeof(storeto->addr.inet));
-  storeto->addr.inet.sin_family= AF_INET;
-  memcpy(&storeto->addr.inet.sin_addr,dgram+cbyte,4);
+  assert(offsetof(adns_rr_addr, addr) + salen <= rrsz);
+  if (addrlen < avail) return adns_s_invaliddata;
+  if (step < 0) step= addrlen;
+  *cbyte_io += step;
+  memset(&storeto->addr, 0, salen);
+  storeto->len= salen;
+  storeto->addr.sa.sa_family= af;
+  memcpy(addrp, oaddr, addrlen);
+
+  return adns_s_ok;
+}
+
+static adns_status pa_addr(const parseinfo *pai, int cbyte,
+                          int max, void *datap) {
+  int err= pap_addr(pai, pai->qu->answer->type & adns_rrt_typemask,
+                   pai->qu->answer->rrsz, &cbyte, max, datap);
+  if (err) return err;
+  if (cbyte != max) return adns_s_invaliddata;
   return adns_s_ok;
 }
 
@@ -664,7 +691,7 @@ static adns_status pap_findaddrs(const parseinfo *pai, adns_rr_hostaddr *ha,
                                 size_t addrsz,
                                 int *cbyte_io, int count, int dmstart) {
   int rri, naddrs;
-  int type, class, rdlen, rdstart, ownermatched;
+  int type, class, rdlen, rdstart, rdend, ownermatched;
   unsigned long ttl;
   adns_status st;
   
@@ -683,8 +710,11 @@ static adns_status pap_findaddrs(const parseinfo *pai, adns_rr_hostaddr *ha,
     if (!adns__vbuf_ensure(&pai->qu->vb, (naddrs+1)*addrsz))
       R_NOMEM;
     adns__update_expires(pai->qu,ttl,pai->now);
-    st= pa_addr(pai, rdstart,rdstart+rdlen, pai->qu->vb.buf + naddrs*addrsz);
+    rdend= rdstart + rdlen;
+    st= pap_addr(pai, adns_r_a, addrsz, &rdstart, rdend,
+                (adns_rr_addr *)(pai->qu->vb.buf + naddrs*addrsz));
     if (st) return st;
+    if (rdstart != rdend) return adns_s_invaliddata;
     naddrs++;
   }
   if (naddrs >= 0) {