5 * Bart De Schuymer <bdschuym@pandora.be>
11 #include <linux/netfilter_bridge/ebtables.h>
12 #include <linux/netfilter_bridge/ebt_log.h>
13 #include <linux/module.h>
15 #include <linux/if_arp.h>
16 #include <linux/spinlock.h>
18 static spinlock_t ebt_log_lock = SPIN_LOCK_UNLOCKED;
20 static int ebt_log_check(const char *tablename, unsigned int hookmask,
21 const struct ebt_entry *e, void *data, unsigned int datalen)
23 struct ebt_log_info *info = (struct ebt_log_info *)data;
25 if (datalen != EBT_ALIGN(sizeof(struct ebt_log_info)))
27 if (info->bitmask & ~EBT_LOG_MASK)
29 if (info->loglevel >= 8)
31 info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0';
43 unsigned char mac_src[ETH_ALEN];
44 unsigned char ip_src[4];
45 unsigned char mac_dst[ETH_ALEN];
46 unsigned char ip_dst[4];
49 static void print_MAC(unsigned char *p)
53 for (i = 0; i < ETH_ALEN; i++, p++)
54 printk("%02x%c", *p, i == ETH_ALEN - 1 ? ' ':':');
57 #define myNIPQUAD(a) a[0], a[1], a[2], a[3]
58 static void ebt_log(const struct sk_buff *skb, const struct net_device *in,
59 const struct net_device *out, const void *data, unsigned int datalen)
61 struct ebt_log_info *info = (struct ebt_log_info *)data;
62 char level_string[4] = "< >";
63 union {struct iphdr iph; struct tcpudphdr ports;
64 struct arphdr arph; struct arppayload arpp;} u;
66 level_string[1] = '0' + info->loglevel;
67 spin_lock_bh(&ebt_log_lock);
69 printk("%s IN=%s OUT=%s ", info->prefix, in ? in->name : "",
70 out ? out->name : "");
72 printk("MAC source = ");
73 print_MAC(eth_hdr(skb)->h_source);
74 printk("MAC dest = ");
75 print_MAC(eth_hdr(skb)->h_dest);
77 printk("proto = 0x%04x", ntohs(eth_hdr(skb)->h_proto));
79 if ((info->bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto ==
81 struct iphdr _iph, *ih;
83 ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
85 printk(" INCOMPLETE IP header");
88 printk(" IP SRC=%u.%u.%u.%u IP DST=%u.%u.%u.%u,",
89 NIPQUAD(ih->saddr), NIPQUAD(ih->daddr));
90 printk(" IP tos=0x%02X, IP proto=%d", u.iph.tos,
92 if (ih->protocol == IPPROTO_TCP ||
93 ih->protocol == IPPROTO_UDP) {
94 struct tcpudphdr _ports, *pptr;
96 pptr = skb_header_pointer(skb, ih->ihl*4,
97 sizeof(_ports), &_ports);
99 printk(" INCOMPLETE TCP/UDP header");
102 printk(" SPT=%u DPT=%u", ntohs(pptr->src),
108 if ((info->bitmask & EBT_LOG_ARP) &&
109 ((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) ||
110 (eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) {
111 struct arphdr _arph, *ah;
113 ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
115 printk(" INCOMPLETE ARP header");
118 printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d",
119 ntohs(ah->ar_hrd), ntohs(ah->ar_pro),
122 /* If it's for Ethernet and the lengths are OK,
123 * then log the ARP payload */
124 if (ah->ar_hrd == htons(1) &&
125 ah->ar_hln == ETH_ALEN &&
126 ah->ar_pln == sizeof(uint32_t)) {
127 struct arppayload _arpp, *ap;
129 ap = skb_header_pointer(skb, sizeof(u.arph),
130 sizeof(_arpp), &_arpp);
132 printk(" INCOMPLETE ARP payload");
135 printk(" ARP MAC SRC=");
136 print_MAC(ap->mac_src);
137 printk(" ARP IP SRC=%u.%u.%u.%u",
138 myNIPQUAD(ap->ip_src));
139 printk(" ARP MAC DST=");
140 print_MAC(ap->mac_dst);
141 printk(" ARP IP DST=%u.%u.%u.%u",
142 myNIPQUAD(ap->ip_dst));
147 spin_unlock_bh(&ebt_log_lock);
150 static struct ebt_watcher log =
152 .name = EBT_LOG_WATCHER,
154 .check = ebt_log_check,
158 static int __init init(void)
160 return ebt_register_watcher(&log);
163 static void __exit fini(void)
165 ebt_unregister_watcher(&log);
170 MODULE_LICENSE("GPL");