From 9436e8cae4709b50ed57f2f5858a3ffad03d5d32 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Wed, 29 Jul 2015 12:22:55 +0200 Subject: resolved: never attempt to resolve loopback addresses via DNS/LLMNR/mDNS We already refuse to resolve "localhost", hence we should also refuse resolving "127.0.0.1" and friends. --- src/resolve/resolved-dns-scope.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'src/resolve') diff --git a/src/resolve/resolved-dns-scope.c b/src/resolve/resolved-dns-scope.c index 927a1ddc26..4bc4157028 100644 --- a/src/resolve/resolved-dns-scope.c +++ b/src/resolve/resolved-dns-scope.c @@ -313,6 +313,11 @@ DnsScopeMatch dns_scope_good_domain(DnsScope *s, int ifindex, uint64_t flags, co if (is_localhost(domain)) return DNS_SCOPE_NO; + /* Never resolve any loopback IP address via DNS, LLMNR or mDNS */ + if (dns_name_endswith(domain, "127.in-addr.arpa") > 0 || + dns_name_equal(domain, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0) + return DNS_SCOPE_NO; + if (s->protocol == DNS_PROTOCOL_DNS) { if (dns_name_endswith(domain, "254.169.in-addr.arpa") == 0 && dns_name_endswith(domain, "0.8.e.f.ip6.arpa") == 0 && -- cgit v1.2.3-54-g00ecf