libxtables: Extend MAC address printing/parsing support

Adding a parser which supports common names for special MAC/mask
combinations and a print routine detecting those special addresses and
printing the respective name allows to consolidate all the various
duplicated implementations.

The side-effects of this change are manageable:

* arptables now accepts "BGA" as alias for the bridge group address
* "mac" match now prints MAC addresses in lower-case which is consistent
  with the remaining code at least

Signed-off-by: Phil Sutter <phil@nwl.cc>

1 files changed, 2 insertions, 48 deletions

diff --git a/iptables/xtables-arp.c b/iptables/xtables-arp.c
index 8632774d..e56bbb4d 100644
--- a/iptables/xtables-arp.c
+++ b/iptables/xtables-arp.c
@@ -135,52 +135,6 @@ static int inverse_for_options[] =
 /* ARPTABLES SPECIFIC NEW FUNCTIONS ADDED HERE */
 /***********************************************/
 
-static unsigned char mac_type_unicast[ETH_ALEN] =   {0,0,0,0,0,0};
-static unsigned char msk_type_unicast[ETH_ALEN] =   {1,0,0,0,0,0};
-static unsigned char mac_type_multicast[ETH_ALEN] = {1,0,0,0,0,0};
-static unsigned char msk_type_multicast[ETH_ALEN] = {1,0,0,0,0,0};
-static unsigned char mac_type_broadcast[ETH_ALEN] = {255,255,255,255,255,255};
-static unsigned char msk_type_broadcast[ETH_ALEN] = {255,255,255,255,255,255};
-
-/*
- * put the mac address into 6 (ETH_ALEN) bytes
- */
-static int getmac_and_mask(char *from, char *to, char *mask)
-{
-	char *p;
-	int i;
-	struct ether_addr *addr;
-
-	if (strcasecmp(from, "Unicast") == 0) {
-		memcpy(to, mac_type_unicast, ETH_ALEN);
-		memcpy(mask, msk_type_unicast, ETH_ALEN);
-		return 0;
-	}
-	if (strcasecmp(from, "Multicast") == 0) {
-		memcpy(to, mac_type_multicast, ETH_ALEN);
-		memcpy(mask, msk_type_multicast, ETH_ALEN);
-		return 0;
-	}
-	if (strcasecmp(from, "Broadcast") == 0) {
-		memcpy(to, mac_type_broadcast, ETH_ALEN);
-		memcpy(mask, msk_type_broadcast, ETH_ALEN);
-		return 0;
-	}
-	if ( (p = strrchr(from, '/')) != NULL) {
-		*p = '\0';
-		if (!(addr = ether_aton(p + 1)))
-			return -1;
-		memcpy(mask, addr, ETH_ALEN);
-	} else
-		memset(mask, 0xff, ETH_ALEN);
-	if (!(addr = ether_aton(from)))
-		return -1;
-	memcpy(to, addr, ETH_ALEN);
-	for (i = 0; i < ETH_ALEN; i++)
-		to[i] &= mask[i];
-	return 0;
-}
-
 static int getlength_and_mask(char *from, uint8_t *to, uint8_t *mask)
 {
 	char *p, *buffer;
@@ -686,7 +640,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table,
 			check_inverse(optarg, &invert, &optind, argc);
 			set_option(&options, OPT_S_MAC, &cs.arp.arp.invflags,
 				   invert);
-			if (getmac_and_mask(argv[optind - 1],
+			if (xtables_parse_mac_and_mask(argv[optind - 1],
 			    cs.arp.arp.src_devaddr.addr, cs.arp.arp.src_devaddr.mask))
 				xtables_error(PARAMETER_PROBLEM, "Problem with specified "
 						"source mac");
@@ -697,7 +651,7 @@ int do_commandarp(struct nft_handle *h, int argc, char *argv[], char **table,
 			set_option(&options, OPT_D_MAC, &cs.arp.arp.invflags,
 				   invert);
 
-			if (getmac_and_mask(argv[optind - 1],
+			if (xtables_parse_mac_and_mask(argv[optind - 1],
 			    cs.arp.arp.tgt_devaddr.addr, cs.arp.arp.tgt_devaddr.mask))
 				xtables_error(PARAMETER_PROBLEM, "Problem with specified "
 						"destination mac");