resolved: fix NSEC proofs for missing TLDs

For the wildcard NSEC check we need to generate an "asterisk" domain, by
prepend the common ancestor with "*.". So far we did that with a simple
strappenda() which is fine for most domains, but doesn't work if the
common ancestor is the root domain as we usually write that as "." in
normalized form, and "*." joined with "." is "*.." and not "*." as it
should be.

Hence, use the clean way out, let's just use dns_name_concat() which
only exists precisely for this reason, to properly concatenate labels.

There's a good chance this actually fixes #5029, as this NSEC proof is
triggered by lookups in the TLD "example", which doesn't exist in the
Internet.
This commit is contained in:
Lennart Poettering 2017-02-14 17:54:30 +01:00
parent c775838ad7
commit 97c2ea2645
1 changed files with 6 additions and 2 deletions

View File

@ -1710,7 +1710,8 @@ static int dnssec_nsec_covers(DnsResourceRecord *rr, const char *name) {
}
static int dnssec_nsec_covers_wildcard(DnsResourceRecord *rr, const char *name) {
const char *common_suffix, *wc;
_cleanup_free_ char *wc = NULL;
const char *common_suffix;
int r;
assert(rr);
@ -1734,7 +1735,10 @@ static int dnssec_nsec_covers_wildcard(DnsResourceRecord *rr, const char *name)
if (r <= 0)
return r;
wc = strjoina("*.", common_suffix);
r = dns_name_concat("*", common_suffix, &wc);
if (r < 0)
return r;
return dns_name_between(dns_resource_key_name(rr->key), wc, rr->nsec.next_domain_name);
}