diff options
Diffstat (limited to 'package/network/services/dnsmasq/patches/0002-Change-behavior-when-RD-bit-unset-in-queries.patch')
| -rw-r--r-- | package/network/services/dnsmasq/patches/0002-Change-behavior-when-RD-bit-unset-in-queries.patch | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/package/network/services/dnsmasq/patches/0002-Change-behavior-when-RD-bit-unset-in-queries.patch b/package/network/services/dnsmasq/patches/0002-Change-behavior-when-RD-bit-unset-in-queries.patch new file mode 100644 index 0000000000..4f787e3cd5 --- /dev/null +++ b/package/network/services/dnsmasq/patches/0002-Change-behavior-when-RD-bit-unset-in-queries.patch @@ -0,0 +1,54 @@ +From 4139298d287eb5c57f4aa53c459cb02fc5be2495 Mon Sep 17 00:00:00 2001 +From: Simon Kelley <simon@thekelleys.org.uk> +Date: Wed, 19 Sep 2018 22:27:11 +0100 +Subject: [PATCH 2/2] Change behavior when RD bit unset in queries. + +Change anti cache-snooping behaviour with queries with the +recursion-desired bit unset. Instead to returning SERVFAIL, we +now always forward, and never answer from the cache. This +allows "dig +trace" command to work. + +Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk> +--- + CHANGELOG | 7 ++++++- + src/rfc1035.c | 8 +++----- + 2 files changed, 9 insertions(+), 6 deletions(-) + +--- a/CHANGELOG ++++ b/CHANGELOG +@@ -59,7 +59,12 @@ version 2.80 + Returning null addresses is a useful technique for ad-blocking. + Thanks to Peter Russell for the suggestion. + +- ++ Change anti cache-snooping behaviour with queries with the ++ recursion-desired bit unset. Instead to returning SERVFAIL, we ++ now always forward, and never answer from the cache. This ++ allows "dig +trace" command to work. ++ ++ + version 2.79 + Fix parsing of CNAME arguments, which are confused by extra spaces. + Thanks to Diego Aguirre for spotting the bug. +--- a/src/rfc1035.c ++++ b/src/rfc1035.c +@@ -1293,16 +1293,14 @@ size_t answer_request(struct dns_header + struct mx_srv_record *rec; + size_t len; + +- if (ntohs(header->ancount) != 0 || ++ /* never answer queries with RD unset, to avoid cache snooping. */ ++ if (!(header->hb3 & HB3_RD) || ++ ntohs(header->ancount) != 0 || + ntohs(header->nscount) != 0 || + ntohs(header->qdcount) == 0 || + OPCODE(header) != QUERY ) + return 0; + +- /* always servfail queries with RD unset, to avoid cache snooping. */ +- if (!(header->hb3 & HB3_RD)) +- return setup_reply(header, qlen, NULL, F_SERVFAIL, 0); +- + /* Don't return AD set if checking disabled. */ + if (header->hb4 & HB4_CD) + sec_data = 0; |