diff options
authorRich Felker <>2016-01-28 19:23:06 -0500
committerRich Felker <>2016-01-28 19:37:35 -0500
commit0fef7ffac114befc94ab5fa794a1754442dcd531 (patch)
parentfe8453d2ee128cfcf8777a19659f1c1f19e052ac (diff)
fix handling of dns response codes
rcode of 3 (NxDomain) was treated as a hard EAI_NONAME failure, but it should instead return 0 (no results) so the caller can continue searching. this will be important for adding search domain support. the top-level caller will automatically return EAI_NONAME if there are zero results at the end. also, the case where rcode is 0 (success) but there are no results was not handled. this happens when the domain exists but there are no A or AAAA records for it. in this case a hard EAI_NONAME should be imposed to inhibit further search, since the name was defined and just does not have any address associated with it. previously a misleading hard failure of EAI_FAIL was reported.
1 files changed, 2 insertions, 1 deletions
diff --git a/src/network/lookup_name.c b/src/network/lookup_name.c
index df9e623e..fb7b5c12 100644
--- a/src/network/lookup_name.c
+++ b/src/network/lookup_name.c
@@ -152,7 +152,8 @@ static int name_from_dns(struct address buf[static MAXADDRS], char canon[static
if (ctx.cnt) return ctx.cnt;
if (alens[0] < 4 || (abuf[0][3] & 15) == 2) return EAI_AGAIN;
- if ((abuf[0][3] & 15) == 3) return EAI_NONAME;
+ if ((abuf[0][3] & 15) == 0) return EAI_NONAME;
+ if ((abuf[0][3] & 15) == 3) return 0;
return EAI_FAIL;