From 6ecea9453ba158edb1949dcac2fc46e1ad4b5bf2 Mon Sep 17 00:00:00 2001 From: "Steinar H. Gunderson" Date: Sat, 29 Sep 2007 13:38:17 +0000 Subject: [PATCH] Handle the root of the DNS tree correctly in ares_expand_name. --- ares/ares_expand_name.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/ares/ares_expand_name.c b/ares/ares_expand_name.c index 7fe025fe4..ffa26e6b5 100644 --- a/ares/ares_expand_name.c +++ b/ares/ares_expand_name.c @@ -74,6 +74,14 @@ int ares_expand_name(const unsigned char *encoded, const unsigned char *abuf, return ARES_ENOMEM; q = *s; + if (len == 0) { + // RFC2181 says this should be ".": the root of the DNS tree. + // Since this function strips trailing dots though, it becomes "" + q[0] = '\0'; + *enclen = 1; // the caller should move one byte to get past this + return ARES_SUCCESS; + } + /* No error-checking necessary; it was all done by name_length(). */ p = encoded; while (*p) -- 2.40.0