Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4ae89ad9 authored by Joe Perches's avatar Joe Perches Committed by Pablo Neira Ayuso
Browse files

etherdevice.h & bridge: netfilter: Add and use ether_addr_equal_masked 



There are code duplications of a masked ethernet address comparison here
so make it a separate function instead.

Miscellanea:

o Neaten alignment of FWINV macro uses to make it clearer for the reader

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 468b021b

include/linux/etherdevice.h

+23 −0
Original line number Diff line number Diff line
@@ -373,6 +373,29 @@ static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2) 
#endif

}



/**

 * ether_addr_equal_masked - Compare two Ethernet addresses with a mask

 * @addr1: Pointer to a six-byte array containing the 1st Ethernet address

 * @addr2: Pointer to a six-byte array containing the 2nd Ethernet address

 * @mask: Pointer to a six-byte array containing the Ethernet address bitmask

 *

 * Compare two Ethernet addresses with a mask, returns true if for every bit

 * set in the bitmask the equivalent bits in the ethernet addresses are equal.

 * Using a mask with all bits set is a slower ether_addr_equal.

 */

static inline bool ether_addr_equal_masked(const u8 *addr1, const u8 *addr2,

					   const u8 *mask)

{

	int i;



	for (i = 0; i < ETH_ALEN; i++) {

		if ((addr1[i] ^ addr2[i]) & mask[i])

			return false;

	}



	return true;

}



/**

 * is_etherdev_addr - Tell if given Ethernet address belongs to the device.

 * @dev: Pointer to a device structure

net/bridge/netfilter/ebt_arp.c

+6 −11
Original line number Diff line number Diff line
@@ -65,7 +65,6 @@ ebt_arp_mt(const struct sk_buff *skb, struct xt_action_param *par) 
	if (info->bitmask & (EBT_ARP_SRC_MAC | EBT_ARP_DST_MAC)) {

		const unsigned char *mp;

		unsigned char _mac[ETH_ALEN];

		uint8_t verdict, i;



		if (ah->ar_hln != ETH_ALEN || ah->ar_hrd != htons(ARPHRD_ETHER))

			return false;
@@ -74,11 +73,9 @@ ebt_arp_mt(const struct sk_buff *skb, struct xt_action_param *par) 
						sizeof(_mac), &_mac);

			if (mp == NULL)

				return false;

			verdict = 0;

			for (i = 0; i < 6; i++)

				verdict |= (mp[i] ^ info->smaddr[i]) &

				       info->smmsk[i];

			if (FWINV(verdict != 0, EBT_ARP_SRC_MAC))

			if (FWINV(!ether_addr_equal_masked(mp, info->smaddr,

							   info->smmsk),

				  EBT_ARP_SRC_MAC))

				return false;

		}
@@ -88,11 +85,9 @@ ebt_arp_mt(const struct sk_buff *skb, struct xt_action_param *par) 
						sizeof(_mac), &_mac);

			if (mp == NULL)

				return false;

			verdict = 0;

			for (i = 0; i < 6; i++)

				verdict |= (mp[i] ^ info->dmaddr[i]) &

					info->dmmsk[i];

			if (FWINV(verdict != 0, EBT_ARP_DST_MAC))

			if (FWINV(!ether_addr_equal_masked(mp, info->dmaddr,

							   info->dmmsk),

				  EBT_ARP_DST_MAC))

				return false;

		}

	}

net/bridge/netfilter/ebt_stp.c

+22 −27
Original line number Diff line number Diff line
@@ -46,7 +46,6 @@ static bool ebt_filter_config(const struct ebt_stp_info *info, 
	const struct ebt_stp_config_info *c;

	u16 v16;

	u32 v32;

	int verdict, i;



	c = &info->config;

	if ((info->bitmask & EBT_STP_FLAGS) &&
@@ -54,66 +53,62 @@ static bool ebt_filter_config(const struct ebt_stp_info *info, 
		return false;

	if (info->bitmask & EBT_STP_ROOTPRIO) {

		v16 = NR16(stpc->root);

		if (FWINV(v16 < c->root_priol ||

		    v16 > c->root_priou, EBT_STP_ROOTPRIO))

		if (FWINV(v16 < c->root_priol || v16 > c->root_priou,

			  EBT_STP_ROOTPRIO))

			return false;

	}

	if (info->bitmask & EBT_STP_ROOTADDR) {

		verdict = 0;

		for (i = 0; i < 6; i++)

			verdict |= (stpc->root[2+i] ^ c->root_addr[i]) &

				   c->root_addrmsk[i];

		if (FWINV(verdict != 0, EBT_STP_ROOTADDR))

		if (FWINV(!ether_addr_equal_masked(&stpc->root[2], c->root_addr,

						   c->root_addrmsk),

			  EBT_STP_ROOTADDR))

			return false;

	}

	if (info->bitmask & EBT_STP_ROOTCOST) {

		v32 = NR32(stpc->root_cost);

		if (FWINV(v32 < c->root_costl ||

		    v32 > c->root_costu, EBT_STP_ROOTCOST))

		if (FWINV(v32 < c->root_costl || v32 > c->root_costu,

			  EBT_STP_ROOTCOST))

			return false;

	}

	if (info->bitmask & EBT_STP_SENDERPRIO) {

		v16 = NR16(stpc->sender);

		if (FWINV(v16 < c->sender_priol ||

		    v16 > c->sender_priou, EBT_STP_SENDERPRIO))

		if (FWINV(v16 < c->sender_priol || v16 > c->sender_priou,

			  EBT_STP_SENDERPRIO))

			return false;

	}

	if (info->bitmask & EBT_STP_SENDERADDR) {

		verdict = 0;

		for (i = 0; i < 6; i++)

			verdict |= (stpc->sender[2+i] ^ c->sender_addr[i]) &

				   c->sender_addrmsk[i];

		if (FWINV(verdict != 0, EBT_STP_SENDERADDR))

		if (FWINV(!ether_addr_equal_masked(&stpc->sender[2],

						   c->sender_addr,

						   c->sender_addrmsk),

			  EBT_STP_SENDERADDR))

			return false;

	}

	if (info->bitmask & EBT_STP_PORT) {

		v16 = NR16(stpc->port);

		if (FWINV(v16 < c->portl ||

		    v16 > c->portu, EBT_STP_PORT))

		if (FWINV(v16 < c->portl || v16 > c->portu, EBT_STP_PORT))

			return false;

	}

	if (info->bitmask & EBT_STP_MSGAGE) {

		v16 = NR16(stpc->msg_age);

		if (FWINV(v16 < c->msg_agel ||

		    v16 > c->msg_ageu, EBT_STP_MSGAGE))

		if (FWINV(v16 < c->msg_agel || v16 > c->msg_ageu,

			  EBT_STP_MSGAGE))

			return false;

	}

	if (info->bitmask & EBT_STP_MAXAGE) {

		v16 = NR16(stpc->max_age);

		if (FWINV(v16 < c->max_agel ||

		    v16 > c->max_ageu, EBT_STP_MAXAGE))

		if (FWINV(v16 < c->max_agel || v16 > c->max_ageu,

			  EBT_STP_MAXAGE))

			return false;

	}

	if (info->bitmask & EBT_STP_HELLOTIME) {

		v16 = NR16(stpc->hello_time);

		if (FWINV(v16 < c->hello_timel ||

		    v16 > c->hello_timeu, EBT_STP_HELLOTIME))

		if (FWINV(v16 < c->hello_timel || v16 > c->hello_timeu,

			  EBT_STP_HELLOTIME))

			return false;

	}

	if (info->bitmask & EBT_STP_FWDD) {

		v16 = NR16(stpc->forward_delay);

		if (FWINV(v16 < c->forward_delayl ||

		    v16 > c->forward_delayu, EBT_STP_FWDD))

		if (FWINV(v16 < c->forward_delayl || v16 > c->forward_delayu,

			  EBT_STP_FWDD))

			return false;

	}

	return true;

net/bridge/netfilter/ebtables.c

+6 −11
Original line number Diff line number Diff line
@@ -130,7 +130,6 @@ ebt_basic_match(const struct ebt_entry *e, const struct sk_buff *skb, 
	const struct ethhdr *h = eth_hdr(skb);

	const struct net_bridge_port *p;

	__be16 ethproto;

	int verdict, i;



	if (skb_vlan_tag_present(skb))

		ethproto = htons(ETH_P_8021Q);
@@ -157,19 +156,15 @@ ebt_basic_match(const struct ebt_entry *e, const struct sk_buff *skb, 
		return 1;



	if (e->bitmask & EBT_SOURCEMAC) {

		verdict = 0;

		for (i = 0; i < 6; i++)

			verdict |= (h->h_source[i] ^ e->sourcemac[i]) &

			   e->sourcemsk[i];

		if (FWINV2(verdict != 0, EBT_ISOURCE))

		if (FWINV2(!ether_addr_equal_masked(h->h_source,

						    e->sourcemac, e->sourcemsk),

			   EBT_ISOURCE))

			return 1;

	}

	if (e->bitmask & EBT_DESTMAC) {

		verdict = 0;

		for (i = 0; i < 6; i++)

			verdict |= (h->h_dest[i] ^ e->destmac[i]) &

			   e->destmsk[i];

		if (FWINV2(verdict != 0, EBT_IDEST))

		if (FWINV2(!ether_addr_equal_masked(h->h_dest,

						    e->destmac, e->destmsk),

			   EBT_IDEST))

			return 1;

	}

	return 0;