From: Lukas Tribus <lukas@ltri.eu>
Date: Thu, 27 Feb 2020 14:47:24 +0000 (+0100)
Subject: BUG/MINOR: dns: ignore trailing dot
X-Git-Tag: v2.2-dev4~109
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=81725b867c20a688c3877421383bfe1ba9348a09;p=thirdparty%2Fhaproxy.git

BUG/MINOR: dns: ignore trailing dot

As per issue #435 a hostname with a trailing dot confuses our DNS code,
as for a zero length DNS label we emit a null-byte. This change makes us
ignore the zero length label instead.

Must be backported to 1.8.
---

diff --git a/src/dns.c b/src/dns.c
index 86147a4170..bbc4f4ac1d 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -1450,6 +1450,12 @@ int dns_str_to_dn_label(const char *str, int str_len, char *dn, int dn_len)
 			if (i == offset)
 				return -1;
 
+			/* ignore trailing dot */
+			if (i + 2 == str_len) {
+				i++;
+				break;
+			}
+
 			dn[offset] = (i - offset);
 			offset = i+1;
 			continue;