diff options
Diffstat (limited to 'net/bridge/netfilter/ebt_ip6.c')
| -rw-r--r-- | net/bridge/netfilter/ebt_ip6.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/net/bridge/netfilter/ebt_ip6.c b/net/bridge/netfilter/ebt_ip6.c new file mode 100644 index 000000000..f3225bc31 --- /dev/null +++ b/net/bridge/netfilter/ebt_ip6.c @@ -0,0 +1,164 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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) && + NF_INVF(info, EBT_IP6_TCLASS, + info->tclass != ipv6_get_dsfield(ih6))) + return false; + if (((info->bitmask & EBT_IP6_SOURCE) && + NF_INVF(info, EBT_IP6_SOURCE, + ipv6_masked_addr_cmp(&ih6->saddr, &info->smsk, + &info->saddr))) || + ((info->bitmask & EBT_IP6_DEST) && + NF_INVF(info, EBT_IP6_DEST, + ipv6_masked_addr_cmp(&ih6->daddr, &info->dmsk, + &info->daddr)))) + 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 (NF_INVF(info, EBT_IP6_PROTO, info->protocol != nexthdr)) + 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 (NF_INVF(info, EBT_IP6_DPORT, + dst < info->dport[0] || + dst > info->dport[1])) + return false; + } + if (info->bitmask & EBT_IP6_SPORT) { + u16 src = ntohs(pptr->tcpudphdr.src); + if (NF_INVF(info, EBT_IP6_SPORT, + src < info->sport[0] || + src > info->sport[1])) + return false; + } + if ((info->bitmask & EBT_IP6_ICMP6) && + NF_INVF(info, EBT_IP6_ICMP6, + 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])) + 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"); |