projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| a0ca215a MN |
1 | /* |
| 2 | * Copyright (C)2006 USAGI/WIDE Project | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License version 2 as | |
| 6 | * published by the Free Software Foundation. | |
| 7 | * | |
| 8 | * Author: | |
| 9 | * Masahide NAKAMURA @USAGI <masahide.nakamura.cz@hitachi.com> | |
| 10 | * | |
| 11 | * Based on net/netfilter/xt_tcpudp.c | |
| 12 | * | |
| 13 | */ | |
| 14 | #include <linux/types.h> | |
| 15 | #include <linux/module.h> | |
| 16 | #include <net/ip.h> | |
| 17 | #include <linux/ipv6.h> | |
| 18 | #include <net/ipv6.h> | |
| 19 | #include <net/mip6.h> | |
| 20 | ||
| 21 | #include <linux/netfilter/x_tables.h> | |
| 22 | #include <linux/netfilter_ipv6/ip6t_mh.h> | |
| 23 | ||
| 24 | MODULE_DESCRIPTION("ip6t_tables match for MH"); | |
| 25 | MODULE_LICENSE("GPL"); | |
| 26 | ||
| 27 | #ifdef DEBUG_IP_FIREWALL_USER | |
| 28 | #define duprintf(format, args...) printk(format , ## args) | |
| 29 | #else | |
| 30 | #define duprintf(format, args...) | |
| 31 | #endif | |
| 32 | ||
| 33 | /* Returns 1 if the type is matched by the range, 0 otherwise */ | |
| 34 | static inline int | |
| 35 | type_match(u_int8_t min, u_int8_t max, u_int8_t type, int invert) | |
| 36 | { | |
| 37 | int ret; | |
| 38 | ||
| 39 | ret = (type >= min && type <= max) ^ invert; | |
| 40 | return ret; | |
| 41 | } | |
| 42 | ||
| 43 | static int | |
| 44 | match(const struct sk_buff *skb, | |
| 45 | const struct net_device *in, | |
| 46 | const struct net_device *out, | |
| 47 | const struct xt_match *match, | |
| 48 | const void *matchinfo, | |
| 49 | int offset, | |
| 50 | unsigned int protoff, | |
| 51 | int *hotdrop) | |
| 52 | { | |
| 53 | struct ip6_mh _mh, *mh; | |
| 54 | const struct ip6t_mh *mhinfo = matchinfo; | |
| 55 | ||
| 56 | /* Must not be a fragment. */ | |
| 57 | if (offset) | |
| 58 | return 0; | |
| 59 | ||
| 60 | mh = skb_header_pointer(skb, protoff, sizeof(_mh), &_mh); | |
| 61 | if (mh == NULL) { | |
| 62 | /* We've been asked to examine this packet, and we | |
| 63 | can't. Hence, no choice but to drop. */ | |
| 64 | duprintf("Dropping evil MH tinygram.\n"); | |
| 65 | *hotdrop = 1; | |
| 66 | return 0; | |
| 67 | } | |
| 68 | ||
| 69 | return type_match(mhinfo->types[0], mhinfo->types[1], mh->ip6mh_type, | |
| 70 | !!(mhinfo->invflags & IP6T_MH_INV_TYPE)); | |
| 71 | } | |
| 72 | ||
| 73 | /* Called when user tries to insert an entry of this type. */ | |
| 74 | static int | |
| 75 | mh_checkentry(const char *tablename, | |
| 76 | const void *entry, | |
| 77 | const struct xt_match *match, | |
| 78 | void *matchinfo, | |
| 79 | unsigned int hook_mask) | |
| 80 | { | |
| 81 | const struct ip6t_mh *mhinfo = matchinfo; | |
| 82 | ||
| 83 | /* Must specify no unknown invflags */ | |
| 84 | return !(mhinfo->invflags & ~IP6T_MH_INV_MASK); | |
| 85 | } | |
| 86 | ||
| 87 | static struct xt_match mh_match = { | |
| 88 | .name = "mh", | |
| 89 | .family = AF_INET6, | |
| 90 | .checkentry = mh_checkentry, | |
| 91 | .match = match, | |
| 92 | .matchsize = sizeof(struct ip6t_mh), | |
| 93 | .proto = IPPROTO_MH, | |
| 94 | .me = THIS_MODULE, | |
| 95 | }; | |
| 96 | ||
| 97 | static int __init ip6t_mh_init(void) | |
| 98 | { | |
| 99 | return xt_register_match(&mh_match); | |
| 100 | } | |
| 101 | ||
| 102 | static void __exit ip6t_mh_fini(void) | |
| 103 | { | |
| 104 | xt_unregister_match(&mh_match); | |
| 105 | } | |
| 106 | ||
| 107 | module_init(ip6t_mh_init); | |
| 108 | module_exit(ip6t_mh_fini); |