From 47b689b1af7bc0bb8c15ef96987b977c98c8ae0b Mon Sep 17 00:00:00 2001 From: Bart De Schuymer Date: Sat, 27 Sep 2003 17:47:56 +0000 Subject: only match non-ip if rule contains no ip specification --- kernel/linux/net/bridge/netfilter/ebt_among.c | 57 +++++++++++---------------- 1 file changed, 22 insertions(+), 35 deletions(-) (limited to 'kernel') diff --git a/kernel/linux/net/bridge/netfilter/ebt_among.c b/kernel/linux/net/bridge/netfilter/ebt_among.c index e4b2268..7c92bee 100644 --- a/kernel/linux/net/bridge/netfilter/ebt_among.c +++ b/kernel/linux/net/bridge/netfilter/ebt_among.c @@ -14,10 +14,6 @@ #include #include -/* -#define DEBUG -*/ - static int ebt_mac_wormhash_contains(const struct ebt_mac_wormhash *wh, const char *mac, uint32_t ip) { @@ -30,6 +26,7 @@ static int ebt_mac_wormhash_contains(const struct ebt_mac_wormhash *wh, int start, limit, i; uint32_t cmp[2] = { 0, 0 }; int key = (const unsigned char) mac[5]; + memcpy(((char *) cmp) + 2, mac, 6); start = wh->table[key]; limit = wh->table[key + 1]; @@ -46,7 +43,9 @@ static int ebt_mac_wormhash_contains(const struct ebt_mac_wormhash *wh, for (i = start; i < limit; i++) { p = &wh->pool[i]; if (cmp[1] == p->cmp[1] && cmp[0] == p->cmp[0]) { - return 1; + if (p->ip == 0) { + return 1; + } } } } @@ -57,7 +56,8 @@ static int ebt_mac_wormhash_check_integrity(const struct ebt_mac_wormhash *wh) { int i; - for (i=0; i<256; i++) { + + for (i = 0; i < 256; i++) { if (wh->table[i] > wh->table[i + 1]) return -0x100 - i; if (wh->table[i] < 0) @@ -70,59 +70,49 @@ static int ebt_mac_wormhash_check_integrity(const struct ebt_mac_wormhash return 0; } -static int get_ip_dst(const struct sk_buff *skb, uint32_t * addr) +static void get_ip_dst(const struct sk_buff *skb, uint32_t * addr) { - if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_IP)) { + if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_IP)) *addr = skb->nh.iph->daddr; - return 1; - } - if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_ARP)) { - + else if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_ARP)) { uint32_t arp_len = sizeof(struct arphdr) + (2 * (((*skb).nh.arph)->ar_hln)) + (2 * (((*skb).nh.arph)->ar_pln)); /* Make sure the packet is long enough. */ if ((((*skb).nh.raw) + arp_len) > (*skb).tail) - return 0; + return; /* IPv4 addresses are always 4 bytes. */ if (((*skb).nh.arph)->ar_pln != sizeof(uint32_t)) - return 0; + return; memcpy(addr, ((*skb).nh.raw) + sizeof(struct arphdr) + (2 * (((*skb).nh.arph)->ar_hln)) + (((*skb).nh.arph)->ar_pln), sizeof(uint32_t)); - return 2; } - return 0; } -static int get_ip_src(const struct sk_buff *skb, uint32_t * addr) +static void get_ip_src(const struct sk_buff *skb, uint32_t * addr) { - if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_IP)) { + if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_IP)) *addr = skb->nh.iph->saddr; - return 1; - } - if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_ARP)) { - + else if (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_ARP)) { uint32_t arp_len = sizeof(struct arphdr) + (2 * (((*skb).nh.arph)->ar_hln)) + (2 * (((*skb).nh.arph)->ar_pln)); /* Make sure the packet is long enough. */ if ((((*skb).nh.raw) + arp_len) > (*skb).tail) - return 0; + return; /* IPv4 addresses are always 4 bytes. */ if (((*skb).nh.arph)->ar_pln != sizeof(uint32_t)) - return 0; + return; memcpy(addr, ((*skb).nh.raw) + sizeof(struct arphdr) + ((((*skb).nh.arph)->ar_hln)), sizeof(uint32_t)); - return 2; } - return 0; } static int ebt_filter_among(const struct sk_buff *skb, @@ -143,14 +133,12 @@ static int ebt_filter_among(const struct sk_buff *skb, get_ip_src(skb, &sip); if (!(info->bitmask & EBT_AMONG_SRC_NEG)) { /* we match only if it contains */ - if (!ebt_mac_wormhash_contains(wh_src, smac, sip)) { + if (!ebt_mac_wormhash_contains(wh_src, smac, sip)) return EBT_NOMATCH; - } } else { /* we match only if it DOES NOT contain */ - if (ebt_mac_wormhash_contains(wh_src, smac, sip)) { + if (ebt_mac_wormhash_contains(wh_src, smac, sip)) return EBT_NOMATCH; - } } } @@ -159,14 +147,12 @@ static int ebt_filter_among(const struct sk_buff *skb, get_ip_dst(skb, &dip); if (!(info->bitmask & EBT_AMONG_DST_NEG)) { /* we match only if it contains */ - if (!ebt_mac_wormhash_contains(wh_dst, dmac, dip)) { + if (!ebt_mac_wormhash_contains(wh_dst, dmac, dip)) return EBT_NOMATCH; - } } else { /* we match only if it DOES NOT contain */ - if (ebt_mac_wormhash_contains(wh_dst, dmac, dip)) { + if (ebt_mac_wormhash_contains(wh_dst, dmac, dip)) return EBT_NOMATCH; - } } } @@ -181,12 +167,13 @@ static int ebt_among_check(const char *tablename, unsigned int hookmask, int expected_length = sizeof(struct ebt_among_info); const struct ebt_mac_wormhash *wh_dst, *wh_src; int err; + wh_dst = ebt_among_wh_dst(info); wh_src = ebt_among_wh_src(info); expected_length += ebt_mac_wormhash_size(wh_dst); expected_length += ebt_mac_wormhash_size(wh_src); - if (datalen < EBT_ALIGN(expected_length)) { + if (datalen != EBT_ALIGN(expected_length)) { printk(KERN_WARNING "ebtables: among: wrong size: %d" "against expected %d, rounded to %d\n", -- cgit v1.2.3