diff options
Diffstat (limited to 'src/resolve/resolved-dns-answer.c')
| -rw-r--r-- | src/resolve/resolved-dns-answer.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/src/resolve/resolved-dns-answer.c b/src/resolve/resolved-dns-answer.c index c359432a7a..f74e440531 100644 --- a/src/resolve/resolved-dns-answer.c +++ b/src/resolve/resolved-dns-answer.c @@ -821,3 +821,40 @@ void dns_answer_dump(DnsAnswer *answer, FILE *f) { fputc('\n', f); } } + +bool dns_answer_has_dname_for_cname(DnsAnswer *a, DnsResourceRecord *cname) { + DnsResourceRecord *rr; + int r; + + assert(cname); + + /* Checks whether the answer contains a DNAME record that indicates that the specified CNAME record is + * synthesized from it */ + + if (cname->key->type != DNS_TYPE_CNAME) + return 0; + + DNS_ANSWER_FOREACH(rr, a) { + _cleanup_free_ char *n = NULL; + + if (rr->key->type != DNS_TYPE_DNAME) + continue; + if (rr->key->class != cname->key->class) + continue; + + r = dns_name_change_suffix(cname->cname.name, rr->dname.name, DNS_RESOURCE_KEY_NAME(rr->key), &n); + if (r < 0) + return r; + if (r == 0) + continue; + + r = dns_name_equal(n, DNS_RESOURCE_KEY_NAME(cname->key)); + if (r < 0) + return r; + if (r > 0) + return 1; + + } + + return 0; +} |