From: Felix Fietkau <nbd@openwrt.org>
Date: Tue, 3 Jun 2014 23:17:46 +0000 (+0200)
Subject: cache: fix host length calculation
X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fmdnsd.git;a=commitdiff_plain;h=6a432a41b9629b6e70a41308f6d9487acf6f4621

cache: fix host length calculation

The previous version was returning negative values for some records due
to unchecked name matching

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---

diff --git a/cache.c b/cache.c
index b5653dd..be26fb6 100644
--- a/cache.c
+++ b/cache.c
@@ -248,6 +248,7 @@ cache_answer(struct uloop_fd *u, uint8_t *base, int blen, char *name, struct dns
 	char *p = NULL;
 	char *name_buf;
 	void *rdata_ptr, *txt_ptr;
+	int host_len = 0;
 
 	if (!(a->class & CLASS_IN))
 		return;
@@ -268,15 +269,11 @@ cache_answer(struct uloop_fd *u, uint8_t *base, int blen, char *name, struct dns
 
 		rdlength = strlen(rdata_buffer);
 
-		if (!strcmp(C_DNS_SD, name)) {
-			cache_entry(u, rdata_buffer, 0, a->ttl);
-			return;
-		}
-
-		if ((rdlength < nlen) && (rdlength - nlen - 1 > 0))
-			return;
+		if (strcmp(C_DNS_SD, name) != 0 &&
+		    nlen + 1 < rdlength && !strcmp(rdata_buffer + rdlength - nlen, name))
+			host_len = rdlength - nlen - 1;
 
-		cache_entry(u, rdata_buffer, rdlength - nlen - 1, a->ttl);
+		cache_entry(u, rdata_buffer, host_len, a->ttl);
 		return;
 
 	case TYPE_SRV: