From: treysis <trey...@gmx.net>
Intented for IPv6 only installations
that have to deal with software that prefers IPv4 above IPv6.
---
src/dnsmasq.h | 3 ++-
src/option.c | 3 +++
src/rfc1035.c | 11 +++++++++++
3 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/src/dnsmasq.h b/src/dnsmasq.h
index 95dc8ae..7eae110 100644
--- a/src/dnsmasq.h
+++ b/src/dnsmasq.h
@@ -272,7 +272,8 @@ struct event_desc {
#define OPT_LOG_DEBUG 62
#define OPT_UMBRELLA 63
#define OPT_UMBRELLA_DEVID 64
-#define OPT_LAST 65
+#define OPT_FILTER_A 65
+#define OPT_LAST 66
#define OPTION_BITS (sizeof(unsigned int)*8)
#define OPTION_SIZE (
(OPT_LAST/OPTION_BITS)+((OPT_LAST%OPTION_BITS)!=0) )
diff --git a/src/option.c b/src/option.c
index 23cf058..a81aa1f 100644
--- a/src/option.c
+++ b/src/option.c
@@ -171,6 +171,7 @@ struct myoption {
#define LOPT_DYNHOST 362
#define LOPT_LOG_DEBUG 363
#define LOPT_UMBRELLA 364
+#define LOPT_FILTER_A 365
#ifdef HAVE_GETOPT_LONG
static const struct option opts[] =
@@ -347,6 +348,7 @@ static const struct myoption opts[] =
{ "dynamic-host", 1, 0, LOPT_DYNHOST },
{ "log-debug", 0, 0, LOPT_LOG_DEBUG },
{ "umbrella", 2, 0, LOPT_UMBRELLA },
+ { "filter-a", 0, 0, LOPT_FILTER_A },
{ NULL, 0, 0, 0 }
};
@@ -530,6 +532,7 @@ static struct {
{ LOPT_DUMPMASK, ARG_ONE, "<hex>", gettext_noop("Mask which
packets to dump"), NULL },
{ LOPT_SCRIPT_TIME, OPT_LEASE_RENEW, NULL, gettext_noop("Call
dhcp-script when lease expiry changes."), NULL },
{ LOPT_UMBRELLA, ARG_ONE, "[=<optspec>]", gettext_noop("Send
Cisco Umbrella identifiers including remote IP."), NULL },
+ { LOPT_FILTER_A, OPT_FILTER_A, NULL, gettext_noop("Filter all A
requests."), NULL },
{ 0, 0, NULL, NULL, NULL }
};
diff --git a/src/rfc1035.c b/src/rfc1035.c
index 5a961b8..a7f83f2 100644
--- a/src/rfc1035.c
+++ b/src/rfc1035.c
@@ -1895,6 +1895,17 @@ size_t answer_request(struct dns_header
*header, char *limit, size_t qlen,
}
}
+ /* filter a forwards */
+ if (qtype == T_A && option_bool(OPT_FILTER_A))
+ {
+ /* return a null reply */
+ ans = 1;
+ if (!dryrun)
+ log_query(F_CONFIG | F_IPV6 | F_NEG, name, &addr, NULL);
+ break;
+ }
+ /* end of filtering a */
+
if (!ans)
return 0; /* failed to answer a question */
}
