| /* |
| * ebt_ip6 |
| * |
| * Authors: |
| * Manohar Castelino <manohar.r.castelino@intel.com> |
| * Kuo-Lang Tseng <kuo-lang.tseng@intel.com> |
| * Jan Engelhardt <jengelh@medozas.de> |
| * |
| * Summary: |
| * This is just a modification of the IPv4 code written by |
| * Bart De Schuymer <bdschuym@pandora.be> |
| * with the changes required to support IPv6 |
| * |
| * Jan, 2008 |
| */ |
| #include <linux/ipv6.h> |
| #include <net/ipv6.h> |
| #include <linux/in.h> |
| #include <linux/module.h> |
| #include <net/dsfield.h> |
| #include <linux/netfilter/x_tables.h> |
| #include <linux/netfilter_bridge/ebtables.h> |
| #include <linux/netfilter_bridge/ebt_ip6.h> |
| |
| union pkthdr { |
| struct { |
| __be16 src; |
| __be16 dst; |
| } tcpudphdr; |
| struct { |
| u8 type; |
| u8 code; |
| } icmphdr; |
| }; |
| |
| static bool |
| ebt_ip6_mt(const struct sk_buff *skb, struct xt_action_param *par) |
| { |
| const struct ebt_ip6_info *info = par->matchinfo; |
| const struct ipv6hdr *ih6; |
| struct ipv6hdr _ip6h; |
| const union pkthdr *pptr; |
| union pkthdr _pkthdr; |
| |
| ih6 = skb_header_pointer(skb, 0, sizeof(_ip6h), &_ip6h); |
| if (ih6 == NULL) |
| return false; |
| if (info->bitmask & EBT_IP6_TCLASS && |
| FWINV(info->tclass != ipv6_get_dsfield(ih6), EBT_IP6_TCLASS)) |
| return false; |
| if ((info->bitmask & EBT_IP6_SOURCE && |
| FWINV(ipv6_masked_addr_cmp(&ih6->saddr, &info->smsk, |
| &info->saddr), EBT_IP6_SOURCE)) || |
| (info->bitmask & EBT_IP6_DEST && |
| FWINV(ipv6_masked_addr_cmp(&ih6->daddr, &info->dmsk, |
| &info->daddr), EBT_IP6_DEST))) |
| return false; |
| if (info->bitmask & EBT_IP6_PROTO) { |
| uint8_t nexthdr = ih6->nexthdr; |
| __be16 frag_off; |
| int offset_ph; |
| |
| offset_ph = ipv6_skip_exthdr(skb, sizeof(_ip6h), &nexthdr, &frag_off); |
| if (offset_ph == -1) |
| return false; |
| if (FWINV(info->protocol != nexthdr, EBT_IP6_PROTO)) |
| return false; |
| if (!(info->bitmask & ( EBT_IP6_DPORT | |
| EBT_IP6_SPORT | EBT_IP6_ICMP6))) |
| return true; |
| |
| /* min icmpv6 headersize is 4, so sizeof(_pkthdr) is ok. */ |
| pptr = skb_header_pointer(skb, offset_ph, sizeof(_pkthdr), |
| &_pkthdr); |
| if (pptr == NULL) |
| return false; |
| if (info->bitmask & EBT_IP6_DPORT) { |
| u16 dst = ntohs(pptr->tcpudphdr.dst); |
| if (FWINV(dst < info->dport[0] || |
| dst > info->dport[1], EBT_IP6_DPORT)) |
| return false; |
| } |
| if (info->bitmask & EBT_IP6_SPORT) { |
| u16 src = ntohs(pptr->tcpudphdr.src); |
| if (FWINV(src < info->sport[0] || |
| src > info->sport[1], EBT_IP6_SPORT)) |
| return false; |
| } |
| if ((info->bitmask & EBT_IP6_ICMP6) && |
| FWINV(pptr->icmphdr.type < info->icmpv6_type[0] || |
| pptr->icmphdr.type > info->icmpv6_type[1] || |
| pptr->icmphdr.code < info->icmpv6_code[0] || |
| pptr->icmphdr.code > info->icmpv6_code[1], |
| EBT_IP6_ICMP6)) |
| return false; |
| } |
| return true; |
| } |
| |
| static int ebt_ip6_mt_check(const struct xt_mtchk_param *par) |
| { |
| const struct ebt_entry *e = par->entryinfo; |
| struct ebt_ip6_info *info = par->matchinfo; |
| |
| if (e->ethproto != htons(ETH_P_IPV6) || e->invflags & EBT_IPROTO) |
| return -EINVAL; |
| if (info->bitmask & ~EBT_IP6_MASK || info->invflags & ~EBT_IP6_MASK) |
| return -EINVAL; |
| if (info->bitmask & (EBT_IP6_DPORT | EBT_IP6_SPORT)) { |
| if (info->invflags & EBT_IP6_PROTO) |
| return -EINVAL; |
| if (info->protocol != IPPROTO_TCP && |
| info->protocol != IPPROTO_UDP && |
| info->protocol != IPPROTO_UDPLITE && |
| info->protocol != IPPROTO_SCTP && |
| info->protocol != IPPROTO_DCCP) |
| return -EINVAL; |
| } |
| if (info->bitmask & EBT_IP6_DPORT && info->dport[0] > info->dport[1]) |
| return -EINVAL; |
| if (info->bitmask & EBT_IP6_SPORT && info->sport[0] > info->sport[1]) |
| return -EINVAL; |
| if (info->bitmask & EBT_IP6_ICMP6) { |
| if ((info->invflags & EBT_IP6_PROTO) || |
| info->protocol != IPPROTO_ICMPV6) |
| return -EINVAL; |
| if (info->icmpv6_type[0] > info->icmpv6_type[1] || |
| info->icmpv6_code[0] > info->icmpv6_code[1]) |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static struct xt_match ebt_ip6_mt_reg __read_mostly = { |
| .name = "ip6", |
| .revision = 0, |
| .family = NFPROTO_BRIDGE, |
| .match = ebt_ip6_mt, |
| .checkentry = ebt_ip6_mt_check, |
| .matchsize = sizeof(struct ebt_ip6_info), |
| .me = THIS_MODULE, |
| }; |
| |
| static int __init ebt_ip6_init(void) |
| { |
| return xt_register_match(&ebt_ip6_mt_reg); |
| } |
| |
| static void __exit ebt_ip6_fini(void) |
| { |
| xt_unregister_match(&ebt_ip6_mt_reg); |
| } |
| |
| module_init(ebt_ip6_init); |
| module_exit(ebt_ip6_fini); |
| MODULE_DESCRIPTION("Ebtables: IPv6 protocol packet match"); |
| MODULE_AUTHOR("Kuo-Lang Tseng <kuo-lang.tseng@intel.com>"); |
| MODULE_LICENSE("GPL"); |