From eff91ee0070f85432e4926403b58ed10cbea1af5 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Tue, 4 Aug 2015 13:53:02 +0200 Subject: resolved: allow dns_cache_put() without a question Currently, dns_cache_put() does a number of things: 1) It unconditionally removes all keys contained in the passed question before adding keys from the newly arrived answers. 2) It puts positive entries into the cache for all RRs contained in the answer. 3) It creates negative entries in the cache for all keys in the question that are not answered. Allow passing q = NULL in the parameters and skip 1) and 3), so we can use that function for mDNS responses. In this case, the question is irrelevant, we are interested in all answers we got. --- src/resolve/resolved-dns-cache.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) (limited to 'src') diff --git a/src/resolve/resolved-dns-cache.c b/src/resolve/resolved-dns-cache.c index efc407dbc6..7ee098397c 100644 --- a/src/resolve/resolved-dns-cache.c +++ b/src/resolve/resolved-dns-cache.c @@ -411,16 +411,17 @@ int dns_cache_put( int owner_family, const union in_addr_union *owner_address) { - unsigned i; + unsigned cache_keys, i; int r; assert(c); - assert(q); - /* First, delete all matching old RRs, so that we only keep - * complete by_key in place. */ - for (i = 0; i < q->n_keys; i++) - dns_cache_remove(c, q->keys[i]); + if (q) { + /* First, if we were passed a question, delete all matching old RRs, + * so that we only keep complete by_key in place. */ + for (i = 0; i < q->n_keys; i++) + dns_cache_remove(c, q->keys[i]); + } if (!answer) return 0; @@ -435,8 +436,13 @@ int dns_cache_put( if (!IN_SET(rcode, DNS_RCODE_SUCCESS, DNS_RCODE_NXDOMAIN)) return 0; + cache_keys = answer->n_rrs; + + if (q) + cache_keys += q->n_keys; + /* Make some space for our new entries */ - dns_cache_make_space(c, answer->n_rrs + q->n_keys); + dns_cache_make_space(c, cache_keys); if (timestamp <= 0) timestamp = now(clock_boottime_or_monotonic()); @@ -448,6 +454,9 @@ int dns_cache_put( goto fail; } + if (!q) + return 0; + /* Third, add in negative entries for all keys with no RR */ for (i = 0; i < q->n_keys; i++) { DnsResourceRecord *soa = NULL; @@ -479,8 +488,11 @@ fail: /* Adding all RRs failed. Let's clean up what we already * added, just in case */ - for (i = 0; i < q->n_keys; i++) - dns_cache_remove(c, q->keys[i]); + if (q) { + for (i = 0; i < q->n_keys; i++) + dns_cache_remove(c, q->keys[i]); + } + for (i = 0; i < answer->n_rrs; i++) dns_cache_remove(c, answer->items[i].rr->key); -- cgit v1.2.3-54-g00ecf