From c3d10a1132ada7baa80914f61abb720f94400465 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Petr=20Men=C5=A1=C3=ADk?= <pemensik@redhat.com>

Date: Tue, 14 Mar 2017 15:23:22 +0100

Subject: [PATCH 1/2] Warn when using label in default mode

---

 src/dnsmasq.c |  2 ++

 src/dnsmasq.h |  3 ++-

 src/network.c | 13 +++++++++++++

 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/dnsmasq.c b/src/dnsmasq.c

index 456b0e8..d2cc7cc 100644

--- a/src/dnsmasq.c

+++ b/src/dnsmasq.c

@@ -771,6 +771,8 @@ int main (int argc, char **argv)

   if (option_bool(OPT_NOWILD))

     warn_bound_listeners();

+  else if (!option_bool(OPT_CLEVERBIND))

+    warn_wild_labels();

   warn_int_names();

diff --git a/src/dnsmasq.h b/src/dnsmasq.h

index a27fbc1..6b44e53 100644

--- a/src/dnsmasq.h

+++ b/src/dnsmasq.h

@@ -522,7 +522,7 @@ struct ipsets {

 struct irec {

   union mysockaddr addr;

   struct in_addr netmask; /* only valid for IPv4 */

-  int tftp_ok, dhcp_ok, mtu, done, warned, dad, dns_auth, index, multicast_done, found;

+  int tftp_ok, dhcp_ok, mtu, done, warned, dad, dns_auth, index, multicast_done, found, label;

   char *name; 

   struct irec *next;

 };

@@ -1252,6 +1252,7 @@ int enumerate_interfaces(int reset);

 void create_wildcard_listeners(void);

 void create_bound_listeners(int die);

 void warn_bound_listeners(void);

+void warn_wild_labels(void);

 void warn_int_names(void);

 int is_dad_listeners(void);

 int iface_check(int family, struct all_addr *addr, char *name, int *auth_dns);

diff --git a/src/network.c b/src/network.c

index eb41624..e5ceb76 100644

--- a/src/network.c

+++ b/src/network.c

@@ -244,6 +244,7 @@ static int iface_allowed(struct iface_param *param, int if_index, char *label,

   int tftp_ok = !!option_bool(OPT_TFTP);

   int dhcp_ok = 1;

   int auth_dns = 0;

+  int is_label = 0;

 #if defined(HAVE_DHCP) || defined(HAVE_TFTP)

   struct iname *tmp;

 #endif

@@ -264,6 +265,8 @@ static int iface_allowed(struct iface_param *param, int if_index, char *label,

   if (!label)

     label = ifr.ifr_name;

+  else

+    is_label = strcmp(label, ifr.ifr_name);

   /* maintain a list of all addresses on all interfaces for --local-service option */

   if (option_bool(OPT_LOCAL_SERVICE))

@@ -482,6 +485,7 @@ static int iface_allowed(struct iface_param *param, int if_index, char *label,

       iface->found = 1;

       iface->done = iface->multicast_done = iface->warned = 0;

       iface->index = if_index;

+      iface->label = is_label;

       if ((iface->name = whine_malloc(strlen(ifr.ifr_name)+1)))

 	{

 	  strcpy(iface->name, ifr.ifr_name);

@@ -1034,6 +1038,15 @@ void warn_bound_listeners(void)

     my_syslog(LOG_WARNING, _("LOUD WARNING: use --bind-dynamic rather than --bind-interfaces to avoid DNS amplification attacks via these interface(s)")); 

 }

+void warn_wild_labels(void)

+{

+  struct irec *iface;

+

+  for (iface = daemon->interfaces; iface; iface = iface->next)

+    if (iface->found && iface->name && iface->label)

+      my_syslog(LOG_WARNING, _("warning: using interface %s instead"), iface->name);

+}

+

 void warn_int_names(void)

 {

   struct interface_name *intname;

-- 

2.9.3