| /* |
| * ebt_log |
| * |
| * Authors: |
| * Bart De Schuymer <bdschuym@pandora.be> |
| * Harald Welte <laforge@netfilter.org> |
| * |
| * April, 2002 |
| * |
| */ |
| |
| #include <linux/netfilter_bridge/ebtables.h> |
| #include <linux/netfilter_bridge/ebt_log.h> |
| #include <linux/netfilter.h> |
| #include <linux/module.h> |
| #include <linux/ip.h> |
| #include <linux/if_arp.h> |
| #include <linux/spinlock.h> |
| |
| static DEFINE_SPINLOCK(ebt_log_lock); |
| |
| static int ebt_log_check(const char *tablename, unsigned int hookmask, |
| const struct ebt_entry *e, void *data, unsigned int datalen) |
| { |
| struct ebt_log_info *info = (struct ebt_log_info *)data; |
| |
| if (datalen != EBT_ALIGN(sizeof(struct ebt_log_info))) |
| return -EINVAL; |
| if (info->bitmask & ~EBT_LOG_MASK) |
| return -EINVAL; |
| if (info->loglevel >= 8) |
| return -EINVAL; |
| info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0'; |
| return 0; |
| } |
| |
| struct tcpudphdr |
| { |
| uint16_t src; |
| uint16_t dst; |
| }; |
| |
| struct arppayload |
| { |
| unsigned char mac_src[ETH_ALEN]; |
| unsigned char ip_src[4]; |
| unsigned char mac_dst[ETH_ALEN]; |
| unsigned char ip_dst[4]; |
| }; |
| |
| static void print_MAC(unsigned char *p) |
| { |
| int i; |
| |
| for (i = 0; i < ETH_ALEN; i++, p++) |
| printk("%02x%c", *p, i == ETH_ALEN - 1 ? ' ':':'); |
| } |
| |
| #define myNIPQUAD(a) a[0], a[1], a[2], a[3] |
| static void |
| ebt_log_packet(unsigned int pf, unsigned int hooknum, |
| const struct sk_buff *skb, const struct net_device *in, |
| const struct net_device *out, const struct nf_loginfo *loginfo, |
| const char *prefix) |
| { |
| unsigned int bitmask; |
| |
| spin_lock_bh(&ebt_log_lock); |
| printk("<%c>%s IN=%s OUT=%s MAC source = ", '0' + loginfo->u.log.level, |
| prefix, in ? in->name : "", out ? out->name : ""); |
| |
| print_MAC(eth_hdr(skb)->h_source); |
| printk("MAC dest = "); |
| print_MAC(eth_hdr(skb)->h_dest); |
| |
| printk("proto = 0x%04x", ntohs(eth_hdr(skb)->h_proto)); |
| |
| if (loginfo->type == NF_LOG_TYPE_LOG) |
| bitmask = loginfo->u.log.logflags; |
| else |
| bitmask = NF_LOG_MASK; |
| |
| if ((bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto == |
| htons(ETH_P_IP)){ |
| struct iphdr _iph, *ih; |
| |
| ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph); |
| if (ih == NULL) { |
| printk(" INCOMPLETE IP header"); |
| goto out; |
| } |
| printk(" IP SRC=%u.%u.%u.%u IP DST=%u.%u.%u.%u, IP " |
| "tos=0x%02X, IP proto=%d", NIPQUAD(ih->saddr), |
| NIPQUAD(ih->daddr), ih->tos, ih->protocol); |
| if (ih->protocol == IPPROTO_TCP || |
| ih->protocol == IPPROTO_UDP) { |
| struct tcpudphdr _ports, *pptr; |
| |
| pptr = skb_header_pointer(skb, ih->ihl*4, |
| sizeof(_ports), &_ports); |
| if (pptr == NULL) { |
| printk(" INCOMPLETE TCP/UDP header"); |
| goto out; |
| } |
| printk(" SPT=%u DPT=%u", ntohs(pptr->src), |
| ntohs(pptr->dst)); |
| } |
| goto out; |
| } |
| |
| if ((bitmask & EBT_LOG_ARP) && |
| ((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) || |
| (eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) { |
| struct arphdr _arph, *ah; |
| |
| ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph); |
| if (ah == NULL) { |
| printk(" INCOMPLETE ARP header"); |
| goto out; |
| } |
| printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d", |
| ntohs(ah->ar_hrd), ntohs(ah->ar_pro), |
| ntohs(ah->ar_op)); |
| |
| /* If it's for Ethernet and the lengths are OK, |
| * then log the ARP payload */ |
| if (ah->ar_hrd == htons(1) && |
| ah->ar_hln == ETH_ALEN && |
| ah->ar_pln == sizeof(uint32_t)) { |
| struct arppayload _arpp, *ap; |
| |
| ap = skb_header_pointer(skb, sizeof(_arph), |
| sizeof(_arpp), &_arpp); |
| if (ap == NULL) { |
| printk(" INCOMPLETE ARP payload"); |
| goto out; |
| } |
| printk(" ARP MAC SRC="); |
| print_MAC(ap->mac_src); |
| printk(" ARP IP SRC=%u.%u.%u.%u", |
| myNIPQUAD(ap->ip_src)); |
| printk(" ARP MAC DST="); |
| print_MAC(ap->mac_dst); |
| printk(" ARP IP DST=%u.%u.%u.%u", |
| myNIPQUAD(ap->ip_dst)); |
| } |
| } |
| out: |
| printk("\n"); |
| spin_unlock_bh(&ebt_log_lock); |
| |
| } |
| |
| static void ebt_log(const struct sk_buff *skb, unsigned int hooknr, |
| const struct net_device *in, const struct net_device *out, |
| const void *data, unsigned int datalen) |
| { |
| struct ebt_log_info *info = (struct ebt_log_info *)data; |
| struct nf_loginfo li; |
| |
| li.type = NF_LOG_TYPE_LOG; |
| li.u.log.level = info->loglevel; |
| li.u.log.logflags = info->bitmask; |
| |
| nf_log_packet(PF_BRIDGE, hooknr, skb, in, out, &li, info->prefix); |
| } |
| |
| static struct ebt_watcher log = |
| { |
| .name = EBT_LOG_WATCHER, |
| .watcher = ebt_log, |
| .check = ebt_log_check, |
| .me = THIS_MODULE, |
| }; |
| |
| static struct nf_logger ebt_log_logger = { |
| .name = "ebt_log", |
| .logfn = &ebt_log_packet, |
| .me = THIS_MODULE, |
| }; |
| |
| static int __init init(void) |
| { |
| int ret; |
| |
| ret = ebt_register_watcher(&log); |
| if (ret < 0) |
| return ret; |
| if (nf_log_register(PF_BRIDGE, &ebt_log_logger) < 0) { |
| printk(KERN_WARNING "ebt_log: not logging via system console " |
| "since somebody else already registered for PF_INET\n"); |
| /* we cannot make module load fail here, since otherwise |
| * ebtables userspace would abort */ |
| } |
| |
| return 0; |
| } |
| |
| static void __exit fini(void) |
| { |
| nf_log_unregister_logger(&ebt_log_logger); |
| ebt_unregister_watcher(&log); |
| } |
| |
| module_init(init); |
| module_exit(fini); |
| MODULE_LICENSE("GPL"); |