the DNS record type that is being sought
The output from the program is written to stdout. It is supposed to be in
-exactly the same format as a traditional namserver response (see RFC 1035) so
+exactly the same format as a traditional nameserver response (see RFC 1035) so
that Exim can process it as normal. At present, no compression is used.
Error messages are written to stderr.
Any DNS record line in a zone file can be prefixed with "DELAY=" and
a number of milliseconds (followed by one space).
-Any DNS record line in a zone file can be prefixed with "DNSSEC ";
+Any DNS record line can be prefixed with "DNSSEC ";
if all the records found by a lookup are marked
as such then the response will have the "AD" bit set.
-Any DNS record line in a zone file can be prefixed with "AA "
+Any DNS record line can be prefixed with "NXDOMAIN ";
+The record will be ignored (but the prefix set still applied);
+This lets us return a DNSSEC NXDOMAIN.
+
+Any DNS record line can be prefixed with "AA "
if all the records found by a lookup are marked
as such then the response will have the "AA" bit set.
rrdomain[0] = 0; /* No previous domain */
(void)fseek(f, 0, SEEK_SET); /* Start again at the beginning */
-if (dnssec) *dnssec = TRUE; /* cancelled by first nonsecure rec found */
-if (aa) *aa = TRUE; /* cancelled by first non-aa rec found */
-
/* Scan for RRs */
while (fgets(CS buffer, sizeof(buffer), f) != NULL)
int qtlen = qtypelen;
BOOL rr_sec = FALSE;
BOOL rr_aa = FALSE;
+ BOOL rr_ignore = FALSE;
int delay = 0;
uint ttl = DEFAULT_TTL;
rr_sec = TRUE;
p += 7;
}
- else if (Ustrncmp(p, US"AA ", 3) == 0) /* tagged as authoritive */
+ if (Ustrncmp(p, US"NXDOMAIN ", 9) == 0) /* ignore record content */
+ {
+ rr_ignore = TRUE;
+ p += 9;
+ }
+ else if (Ustrncmp(p, US"AA ", 3) == 0) /* tagged as authoritative */
{
rr_aa = TRUE;
p += 3;
/* The domain matches */
- if (yield == HOST_NOT_FOUND) yield = NO_DATA;
+ if (yield == HOST_NOT_FOUND)
+ {
+ yield = NO_DATA;
+ if (dnssec) *dnssec = TRUE; /* cancelled by first nonsecure rec found */
+ if (aa) *aa = TRUE; /* cancelled by first non-aa rec found */
+ }
/* Compare RR types; a CNAME record is always returned */
if (aa && !rr_aa)
*aa = FALSE; /* cancel AA return */
+ if (rr_ignore) continue;
+
yield = 0;
*countptr = *countptr + 1;
header->ancount = htons(count);
/* If the AA bit should be set (as indicated by the AA prefix in the zone file),
-we are expected to return some records in the authortive section. Bind9: If
-there is data in the answer section, the authoritive section contains the NS
+we are expected to return some records in the authoritative section. Bind9: If
+there is data in the answer section, the authoritative section contains the NS
records, otherwise it contains the SOA record. Currently we mimic this
behaviour for the first case (there is some answer record).
*/