|
 |
85f98a |
From 10642f9fb350e118d88e995b8dfa2badc7be1c30 Mon Sep 17 00:00:00 2001
|
|
|
85f98a |
From: Petr Mensik <pemensik@redhat.com>
|
|
|
85f98a |
Date: Wed, 11 Dec 2019 13:41:57 +0100
|
|
|
85f98a |
Subject: [PATCH] Restore ability to answer non-recursive requests
|
|
|
85f98a |
|
|
|
85f98a |
Instead, check only local configured entries are answered without
|
|
|
85f98a |
rdbit set. All cached replies are still denied, but locally configured
|
|
|
85f98a |
names are available with both recursion and without it.
|
|
|
85f98a |
---
|
|
|
85f98a |
src/rfc1035.c | 27 ++++++++++++++-------------
|
|
|
85f98a |
1 file changed, 14 insertions(+), 13 deletions(-)
|
|
|
85f98a |
|
|
|
85f98a |
diff --git a/src/rfc1035.c b/src/rfc1035.c
|
|
|
85f98a |
index 6b3bb27..6a7c154 100644
|
|
|
85f98a |
--- a/src/rfc1035.c
|
|
|
85f98a |
+++ b/src/rfc1035.c
|
|
|
85f98a |
@@ -1262,7 +1262,11 @@ static unsigned long crec_ttl(struct crec *crecp, time_t now)
|
|
|
85f98a |
else
|
|
|
85f98a |
return daemon->max_ttl;
|
|
|
85f98a |
}
|
|
|
85f98a |
-
|
|
|
85f98a |
+
|
|
|
85f98a |
+static int cache_validated(const struct crec *crecp)
|
|
|
85f98a |
+{
|
|
|
85f98a |
+ return (option_bool(OPT_DNSSEC_VALID) && !(crecp->flags & F_DNSSECOK));
|
|
|
85f98a |
+}
|
|
|
85f98a |
|
|
|
85f98a |
/* return zero if we can't answer from cache, or packet size if we can */
|
|
|
85f98a |
size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
|
|
|
85f98a |
@@ -1281,6 +1285,7 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
|
|
|
85f98a |
int nxdomain = 0, auth = 1, trunc = 0, sec_data = 1;
|
|
|
85f98a |
struct mx_srv_record *rec;
|
|
|
85f98a |
size_t len;
|
|
|
85f98a |
+ int rd_bit;
|
|
|
85f98a |
// Make sure we do not underflow here too.
|
|
|
85f98a |
if (qlen > (limit - ((char *)header))) return 0;
|
|
|
85f98a |
|
|
|
85f98a |
@@ -1290,10 +1295,8 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
|
|
|
85f98a |
OPCODE(header) != QUERY )
|
|
|
85f98a |
return 0;
|
|
|
85f98a |
|
|
|
85f98a |
- /* always servfail queries with RD unset, to avoid cache snooping. */
|
|
|
85f98a |
- if (!(header->hb3 & HB3_RD))
|
|
|
85f98a |
- return setup_reply(header, qlen, NULL, F_SERVFAIL, 0);
|
|
|
85f98a |
-
|
|
|
85f98a |
+ rd_bit = (header->hb3 & HB3_RD);
|
|
|
85f98a |
+
|
|
|
85f98a |
/* Don't return AD set if checking disabled. */
|
|
|
85f98a |
if (header->hb4 & HB4_CD)
|
|
|
85f98a |
sec_data = 0;
|
|
|
85f98a |
@@ -1458,9 +1461,8 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
|
|
|
85f98a |
/* Don't use cache when DNSSEC data required, unless we know that
|
|
|
85f98a |
the zone is unsigned, which implies that we're doing
|
|
|
85f98a |
validation. */
|
|
|
85f98a |
- if ((crecp->flags & (F_HOSTS | F_DHCP | F_CONFIG)) ||
|
|
|
85f98a |
- !do_bit ||
|
|
|
85f98a |
- (option_bool(OPT_DNSSEC_VALID) && !(crecp->flags & F_DNSSECOK)))
|
|
|
85f98a |
+ if ((crecp->flags & (F_HOSTS | F_DHCP | F_CONFIG)) ||
|
|
|
85f98a |
+ (rd_bit && (!do_bit || cache_validated(crecp)) ))
|
|
|
85f98a |
{
|
|
|
85f98a |
do
|
|
|
85f98a |
{
|
|
|
85f98a |
@@ -1657,8 +1659,7 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
|
|
|
85f98a |
|
|
|
85f98a |
/* If the client asked for DNSSEC don't use cached data. */
|
|
|
85f98a |
if ((crecp->flags & (F_HOSTS | F_DHCP | F_CONFIG)) ||
|
|
|
85f98a |
- !do_bit ||
|
|
|
85f98a |
- (option_bool(OPT_DNSSEC_VALID) && !(crecp->flags & F_DNSSECOK)))
|
|
|
85f98a |
+ (rd_bit && (!do_bit || cache_validated(crecp)) ))
|
|
|
85f98a |
do
|
|
|
85f98a |
{
|
|
|
85f98a |
/* don't answer wildcard queries with data not from /etc/hosts
|
|
|
85f98a |
@@ -1741,8 +1742,8 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
|
|
|
85f98a |
if (qtype == T_CNAME || qtype == T_ANY)
|
|
|
85f98a |
{
|
|
|
85f98a |
if ((crecp = cache_find_by_name(NULL, name, now, F_CNAME | (dryrun ? F_NO_RR : 0))) &&
|
|
|
85f98a |
- (qtype == T_CNAME || (crecp->flags & F_CONFIG)) &&
|
|
|
85f98a |
- ((crecp->flags & F_CONFIG) || !do_bit || (option_bool(OPT_DNSSEC_VALID) && !(crecp->flags & F_DNSSECOK))))
|
|
|
85f98a |
+ ((qtype == T_CNAME && rd_bit) || (crecp->flags & F_CONFIG)) &&
|
|
|
85f98a |
+ ((crecp->flags & F_CONFIG) || (!do_bit || cache_validated(crecp))))
|
|
|
85f98a |
{
|
|
|
85f98a |
if (!(crecp->flags & F_DNSSECOK))
|
|
|
85f98a |
sec_data = 0;
|
|
|
85f98a |
@@ -1780,7 +1781,7 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
|
|
|
85f98a |
}
|
|
|
85f98a |
}
|
|
|
85f98a |
|
|
|
85f98a |
- if (!found && (option_bool(OPT_SELFMX) || option_bool(OPT_LOCALMX)) &&
|
|
|
85f98a |
+ if (!found && (option_bool(OPT_SELFMX) || option_bool(OPT_LOCALMX)) &&
|
|
|
85f98a |
cache_find_by_name(NULL, name, now, F_HOSTS | F_DHCP | F_NO_RR))
|
|
|
85f98a |
{
|
|
|
85f98a |
ans = 1;
|
|
|
85f98a |
--
|
|
|
85f98a |
2.21.0
|
|
|
85f98a |
|