diff options
| -rw-r--r-- | LICENSE | 339 | ||||
| -rw-r--r-- | Makefile | 24 | ||||
| -rw-r--r-- | README | 3 | ||||
| -rw-r--r-- | dkms.conf | 7 | ||||
| -rw-r--r-- | ip6t_MAP66.c | 307 | ||||
| -rw-r--r-- | ip6t_MAP66.h | 22 | ||||
| -rw-r--r-- | libip6t_MAP66.c | 170 |
7 files changed, 872 insertions, 0 deletions
@@ -0,0 +1,339 @@ + GNU GENERAL PUBLIC LICENSE + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change free +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Lesser General Public License instead.) You can apply it to +your programs, too. + + When we speak of free software, we are referring to freedom, not +price. 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It is safest +to attach them to the start of each source file to most effectively +convey the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + <one line to give the program's name and a brief idea of what it does.> + Copyright (C) <year> <name of author> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + +Also add information on how to contact you by electronic and paper mail. + +If the program is interactive, make it output a short notice like this +when it starts in an interactive mode: + + Gnomovision version 69, Copyright (C) year name of author + Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, the commands you use may +be called something other than `show w' and `show c'; they could even be +mouse-clicks or menu items--whatever suits your program. + +You should also get your employer (if you work as a programmer) or your +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the program + `Gnomovision' (which makes passes at compilers) written by James Hacker. + + <signature of Ty Coon>, 1 April 1989 + Ty Coon, President of Vice + +This General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may +consider it more useful to permit linking proprietary applications with the +library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..a3f5a2c --- /dev/null +++ b/Makefile @@ -0,0 +1,24 @@ +obj-m := ip6t_MAP66.o +KVERSION := $(shell uname -r) +KPATH := /lib/modules/$(KVERSION)/build +IPTABLES_VERSION := $(shell ip6tables --version|sed 's/^.*\([[:digit:]]\+\.[[:digit:]]\+\.[[:digit:]]\+\).*/\1/') +IPTABLES_VERSION_CODE := $(shell echo $$(( $$(echo $(IPTABLES_VERSION)|sed 's/^.*\([[:digit:]]\+\)\.\([[:digit:]]\+\)\.\([[:digit:]]\+\).*/\1 * 65536 + \2 * 256 + \3/') ))) + +all: libip6t_MAP66.so + $(MAKE) -C $(KPATH) M=$(PWD) modules + +libip6t_MAP66.so: libip6t_MAP66.o + gcc -shared -o $@ $< + +libip6t_MAP66.o: libip6t_MAP66.c ip6t_MAP66.h Makefile + gcc $(CFLAGS) -DIPTABLES_VERSION=\"$(IPTABLES_VERSION)\" -DIPTABLES_VERSION_CODE=$(IPTABLES_VERSION_CODE) -D_LARGEFILE_SOURCE=1 -D_LARGE_FILES -D_FILE_OFFSET_BITS=64 -D_REENTRANT -Werror -Wall -Waggregate-return -Wmissing-declarations -Wmissing-prototypes -Wredundant-decls -Wshadow -Winline -pipe -DXTABLES_LIBDIR=\"/usr/local/libexec/xtables\" -D_INIT=libip6t_MAP66_init -DPIC -fPIC -g -O2 -o $@ -c $< + +clean: + $(MAKE) -C /lib/modules/$(KVERSION)/build M=$(PWD) clean + rm -f *.so + rm -f *~ + +install: /lib/xtables/libip6t_MAP66.so + +/lib/xtables/libip6t_MAP66.so: libip6t_MAP66.so + cp $< $@ @@ -0,0 +1,3 @@ +You need "iptables-dev", "dkms" and "linux-headers". For a DKMS +template, see https://wiki.kubuntu.org/Kernel/Dev/DKMSPackaging + diff --git a/dkms.conf b/dkms.conf new file mode 100644 index 0000000..d5ecc43 --- /dev/null +++ b/dkms.conf @@ -0,0 +1,7 @@ +PACKAGE_NAME="ip6t_MAP66" +PACKAGE_VERSION="0.2" +CLEAN="make clean" +MAKE[0]="make all KVERSION=$kernelver" +BUILT_MODULE_NAME[0]="ip6t_MAP66" +DEST_MODULE_LOCATION[0]="/updates" +AUTOINSTALL="yes" diff --git a/ip6t_MAP66.c b/ip6t_MAP66.c new file mode 100644 index 0000000..fb0a243 --- /dev/null +++ b/ip6t_MAP66.c @@ -0,0 +1,307 @@ +/* + * MAP66: Network Address Translation IPv6-to-IPv6 as + * proposed in the IETF's second NAT66 draft document. + * (c) 2010 sven-ola()gmx.de + */ + +#include <linux/module.h> +#include <linux/version.h> +#include <linux/netfilter_ipv6/ip6_tables.h> +#include <net/ipv6.h> + +#include "ip6t_MAP66.h" + +MODULE_AUTHOR("Sven-Ola <sven-ola()gmx.de>"); +MODULE_DESCRIPTION("Xtables: MAP66 - IPv6 to IPv6 SNAT"); +MODULE_LICENSE("GPL"); + +#undef MAP66_DEBUG +#ifdef MAP66_DEBUG +/* Use lock to serialize, so printks don't overlap */ +static DEFINE_SPINLOCK(MAP66_lock); +#endif + +/* One's complement add */ +static inline u_int16_t add16( + u_int16_t a, + u_int16_t b) +{ + a += b; + return a + (a < b); +} + +/* Calc one's complement csum */ +static inline u_int16_t csum16(const u_int16_t *buf, int len) +{ + u_int16_t csum = 0; + while(len--) csum = add16(csum, *buf++); + return csum; +} + +/* Perform checksum neutral mapping */ +static void map16( + struct in6_addr* addr, + unsigned char mask, + const struct in6_addr* to, + u_int16_t csum) +{ + csum = add16( + *((u_int16_t*)addr + mask), + add16(csum16((const u_int16_t *)addr, mask), csum) + ); + if (csum == 0xffff) csum = 0x0000; + *((u_int16_t *)addr + mask) = csum; + memcpy(addr, to, sizeof(u_int16_t) * mask); +} + +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0) +# define rcu_dereference(p) p +# define ipv6_addr_equal(a, b) 0 == ipv6_addr_cmp(a, b) +# define ipv6_hdr(sbk) skb->nh.ipv6h +# ifndef bool +# define bool int +# define false 0 +# define true 0 +# endif +# define xt_target ip6t_target +# define __read_mostly +# define xt_register_target ip6t_register_target +# define xt_unregister_target ip6t_unregister_target +#endif + +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,24) +# define NF_INET_PRE_ROUTING NF_IP6_PRE_ROUTING +# define NF_INET_POST_ROUTING NF_IP6_POST_ROUTING +#endif + +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,26) + +struct xt_target_param { + const struct net_device *in, *out; + const void *targinfo; + unsigned int hooknum; +}; + +struct xt_tgchk_param { + void *targinfo; +}; + +#endif + +static bool is_my_ipv6_addr( + const struct net_device *dev, + const struct in6_addr *addr) +{ +#ifdef MAP66_DEBUG +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,28) + printk("MAP66: is_my_ipv6_addr(%s, " NIP6_FMT ")\n", NULL != dev ? dev->name : "", NIP6(*addr)); +#else + printk("MAP66: is_my_ipv6_addr(%s, %pI6)\n", NULL != dev ? dev->name : "", addr); +#endif +#endif + if (NULL != dev) { + const struct inet6_ifaddr *ifa; + const struct inet6_dev *idev = rcu_dereference(dev->ip6_ptr); + for (ifa = idev->addr_list; NULL != ifa; ifa = ifa->if_next) { +#ifdef MAP66_DEBUG +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,28) + printk("MAP66: cmp " NIP6_FMT "\n", NIP6(ifa->addr)); +#else + printk("MAP66: cmp %pI6\n", &ifa->addr); +#endif +#endif + if (ipv6_addr_equal(&ifa->addr, addr)) return true; + } + } + return false; +} + +static unsigned int MAP66_tg6( + struct sk_buff *skb, + const struct xt_target_param *par) +{ + struct ipv6hdr *hdr = ipv6_hdr(skb); + const struct ip6t_MAP66_info *info = (const struct ip6t_MAP66_info *)par->targinfo; + +#ifdef MAP66_DEBUG + spin_lock_bh(&MAP66_lock); +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,28) + printk("MAP66i: in=%s, out=%s, saddr=" NIP6_FMT ", daddr=" NIP6_FMT "\n", + NULL != par->in ? par->in->name : "", + NULL != par->out ? par->out->name : "", + NIP6(hdr->saddr), NIP6(hdr->daddr)); +#else + printk("MAP66i: in=%s, out=%s, saddr=%pI6, daddr=%pI6\n", + NULL != par->in ? par->in->name : "", + NULL != par->out ? par->out->name : "", + &hdr->saddr, &hdr->daddr); +#endif +#endif + + switch(par->hooknum) { + case NF_INET_PRE_ROUTING: +#ifdef MAP66_DEBUG + printk("MAP66 PRE, spoof=%d\n", 0 != (IP6T_MAP66_OPT_NOSPOOF & info->mapflags)); +#endif + if (0 != (IP6T_MAP66_OPT_NOSPOOF & info->mapflags) || + !is_my_ipv6_addr(par->in, &hdr->daddr)) + { + map16(&hdr->daddr, info->prefixlength, &info->prefix, info->prefixcsum); + } + break; + case NF_INET_POST_ROUTING: +#ifdef MAP66_DEBUG + printk("MAP66 POST, spoof=%d\n", 0 != (IP6T_MAP66_OPT_NOSPOOF & info->mapflags)); +#endif + map16(&hdr->saddr, info->prefixlength, &info->prefix, info->prefixcsum); + if (0 == (IP6T_MAP66_OPT_NOSPOOF & info->mapflags) && + is_my_ipv6_addr(par->out, &hdr->saddr)) + { +#ifdef MAP66_DEBUG + spin_unlock_bh(&MAP66_lock); +#endif + return NF_DROP; + } + break; + default: +#ifdef MAP66_DEBUG + printk("MAP66: unsupported hook: %d\n", par->hooknum); +#endif + break; + } + +#ifdef MAP66_DEBUG +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,28) + printk("MAP66i: in=%s, out=%s, saddr=" NIP6_FMT ", daddr=" NIP6_FMT "\n", + NULL != par->in ? par->in->name : "", + NULL != par->out ? par->out->name : "", + NIP6(hdr->saddr), NIP6(hdr->daddr)); +#else + printk("MAP66i: in=%s, out=%s, saddr=%pI6, daddr=%pI6\n", + NULL != par->in ? par->in->name : "", + NULL != par->out ? par->out->name : "", + &hdr->saddr, &hdr->daddr); +#endif + spin_unlock_bh(&MAP66_lock); +#endif + + return IP6T_CONTINUE; +} + +static bool MAP66_tg6_check( + const struct xt_tgchk_param *par) +{ + const struct ip6t_MAP66_info *info = (const struct ip6t_MAP66_info *)par->targinfo; + + if (0 >= info->prefixlength || 8 <= info->prefixlength) { + printk("MAP66: Unsupported prefix length /%d\n", 16 * info->prefixlength); + return false; + } + return true; +} + +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0) + +static unsigned int MAP66_tg6_24( + struct sk_buff **pskb, + unsigned int hooknum, + const struct net_device *in, + const struct net_device *out, + const void *targinfo, + void *userinfo) +{ + const struct xt_target_param par = { + .in = in, + .out = out, + .hooknum = hooknum, + .targinfo = targinfo, + }; + return MAP66_tg6(*pskb, &par); +} + +static int MAP66_tg6_check_24( + const char *table, + const struct ip6t_entry *entry, + void *targinfo, + unsigned int targinfosize, + unsigned int hook_mask) +{ + const struct xt_tgchk_param par = { + .targinfo = targinfo, + }; + if (0 != (hook_mask & ~((1 << NF_IP6_PRE_ROUTING) | (1 << NF_IP6_POST_ROUTING)))) { + printk("MAP66: Only valid for PRE_ROUTING or POST_ROUTING.\n"); + return 0; + } + return MAP66_tg6_check(&par); +} + +#elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28) + +static unsigned int MAP66_tg6_26( + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + unsigned int hooknum, + const struct xt_target *target, + const void *targinfo) +{ + const struct xt_target_param par = { + .in = in, + .out = out, + .hooknum = hooknum, + .targinfo = targinfo, + }; + return MAP66_tg6(skb, &par); +} + +static bool MAP66_tg6_check_26( + const char *table, + const void *entryinfo, + const struct xt_target *target, + void *targinfo, + unsigned int hook_mask) +{ + const struct xt_tgchk_param par = { + .targinfo = targinfo, + }; + return MAP66_tg6_check(&par); +} + +#endif + +static struct xt_target MAP66_tg6_reg __read_mostly = { + .name = "MAP66", +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0) + .target = MAP66_tg6_24, + .checkentry = MAP66_tg6_check_24, +#else +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28) + .family = AF_INET6, + .target = MAP66_tg6_26, + .checkentry = MAP66_tg6_check_26, + .destroy = NULL, +#else + .family = NFPROTO_IPV6, + .target = MAP66_tg6, + .checkentry = MAP66_tg6_check, +#endif + .targetsize = sizeof(struct ip6t_MAP66_info), + .table = "mangle", + .hooks = (1 << NF_INET_POST_ROUTING) | (1 << NF_INET_PRE_ROUTING), +#endif + .me = THIS_MODULE, +}; + +static int __init MAP66_tg6_init(void) +{ + return xt_register_target(&MAP66_tg6_reg); +} + +static void __exit MAP66_tg6_exit(void) +{ + xt_unregister_target(&MAP66_tg6_reg); +} + +module_init(MAP66_tg6_init); +module_exit(MAP66_tg6_exit); diff --git a/ip6t_MAP66.h b/ip6t_MAP66.h new file mode 100644 index 0000000..652c1c2 --- /dev/null +++ b/ip6t_MAP66.h @@ -0,0 +1,22 @@ +/* + * MAP66: Network Address Translation IPv6-to-IPv6 as + * proposed in the IETF's second NAT66 draft document. + * (c) 2010 sven-ola()gmx.de + */ + +#ifndef _IP6T_MAP66_H +#define _IP6T_MAP66_H + +#define IP6T_MAP66_OPT_TO 0x01 +#define IP6T_MAP66_OPT_NOSPOOF 0x02 + +struct ip6t_MAP66_info { + struct in6_addr prefix; /* The prefix to map to */ + u_int16_t prefixcsum; /* Pre-calculated csum */ + u_int8_t prefixlength; /* Prefix length DIV sizeof(u_int16_t) */ + u_int8_t mapflags; /* Some flags */ +}; + +extern void _init(void); + +#endif /*_IPT_MAP66_H*/ diff --git a/libip6t_MAP66.c b/libip6t_MAP66.c new file mode 100644 index 0000000..a8a0f72 --- /dev/null +++ b/libip6t_MAP66.c @@ -0,0 +1,170 @@ +/* + * MAP66: Network Address Translation IPv6-to-IPv6 as + * proposed in the IETF's second NAT66 draft document. + * (c) 2010 sven-ola()gmx.de + */ + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <getopt.h> +#include <arpa/inet.h> + +#define IPTABLES_VERSION_CMP(a,b,c) (((a) << 16) + ((b) << 8) + (c)) + +#if IPTABLES_VERSION_CODE < IPTABLES_VERSION_CMP(1,4,0) +# include <ip6tables.h> +# define xt_entry_target ip6t_entry_target +# define void_entry struct ip6t_entry +# define void_ip6 struct ip6t_ip6 +# define XT_ALIGN IP6T_ALIGN +#else +# include <xtables.h> +# define void_entry void +# define void_ip6 void +#endif + +#if IPTABLES_VERSION_CODE < IPTABLES_VERSION_CMP(1,4,1) +# define xtables_target ip6tables_target +# define XTABLES_VERSION IPTABLES_VERSION +# define xtables_register_target register_target6 +#endif + +#if IPTABLES_VERSION_CODE < IPTABLES_VERSION_CMP(1,4,3) +# define xtables_error exit_error +# define xtables_check_inverse check_inverse +# define NFPROTO_IPV6 PF_INET6 +#endif + +#include "ip6t_MAP66.h" + +/* One's complement add */ +static inline u_int16_t add16( + u_int16_t a, + u_int16_t b) +{ + a += b; + return a + (a < b); +} + +/* Calc one's complement csum */ +static inline u_int16_t csum16(const u_int16_t *buf, int len) +{ + u_int16_t csum = 0; + while(len--) csum = add16(csum, *buf++); + return csum; +} + +static void MAP66_help(void) +{ + printf( +"MAP66 target options\n" +" --to ipv6addr/prefixlength (External IPv6 address)\n" +" --nospoof (Disables spoof check)\n" +"\n" +"Note: you need two ip6tables rules to map an internal network\n" +"using ULAs to an external network with official IPv6 address.\n" +"\n" +"Example:\n" +"\n" +"ip6tables -t mangle -I PREROUTING -i eth0 -d 2001:0DB8:0001::/48 -j MAP66 --to FD01:0203:0405::/48\n" +"ip6tables -t mangle -I POSTROUTING -o eth0 -s FD01:0203:0405::/48 -j MAP66 --to 2001:0DB8:0001::/48\n"); +} + +static int MAP66_parse( + int c, + char **argv, + int invert, + unsigned int *flags, + const void_entry *entry, + struct xt_entry_target **target) +{ + int i; + char *p; + struct ip6t_MAP66_info* info = (struct ip6t_MAP66_info*)(*target)->data; + + switch(c) { + case '1': + if (!optarg) { + xtables_error(PARAMETER_PROBLEM, "--to: You must specify a value"); + } + if (xtables_check_inverse(optarg, &invert, NULL, 0 +#if IPTABLES_VERSION_CODE >= IPTABLES_VERSION_CMP(1,4,6) + ,argv +#endif + )) { + xtables_error(PARAMETER_PROBLEM, "Unexpected `!' after --to"); + } + if (0 != (IP6T_MAP66_OPT_TO & *flags)) { + xtables_error(PARAMETER_PROBLEM, "Multiple --to not supported"); + } + *flags |= IP6T_MAP66_OPT_TO; + if (NULL == (p = strchr(optarg, '/'))) { + xtables_error(PARAMETER_PROBLEM, "Missing '/' character in --to: \"%s\"", optarg); + } + *p = '\0'; + if (1 != inet_pton(AF_INET6, optarg, &info->prefix)) { + xtables_error(PARAMETER_PROBLEM, "Invalid IPv6 address in --to: \"%s\"", optarg); + } + i = atoi(p + 1); + if (0 >= i || 128 <= i || 0 != i % 16) { + xtables_error(PARAMETER_PROBLEM, "Invalid prefix length in --to: \"%s\" (use /112, /96 .. /16)", p + 1); + } + info->prefixlength = i / 16; + info->prefixcsum = ~csum16((const u_int16_t *)&info->prefix, info->prefixlength); + return 1; + break; + case '2': + if (0 != (IP6T_MAP66_OPT_NOSPOOF & *flags)) { + xtables_error(PARAMETER_PROBLEM, "Multiple --nospoof not supported"); + } + info->mapflags |= IP6T_MAP66_OPT_NOSPOOF; + *flags |= IP6T_MAP66_OPT_NOSPOOF; + return 1; + break; + } + return 0; +} + +static void MAP66_check(unsigned int flags) +{ + if (!(flags & IP6T_MAP66_OPT_TO)) { + xtables_error(PARAMETER_PROBLEM, "You must specify --to"); + } +} + +static void MAP66_save( + const void_ip6 *ip, + const struct xt_entry_target *target) +{ + char s[50+1]; + const struct ip6t_MAP66_info* info = (struct ip6t_MAP66_info*)target->data; + printf("--to %s/%d ", inet_ntop(AF_INET6, &info->prefix, s, sizeof(s)), 16 * info->prefixlength); + if (0 != (IP6T_MAP66_OPT_NOSPOOF & info->mapflags)) printf("--nospoof "); +} + +static struct option MAP66_opts[] = { + { .name = "to", .has_arg = 1, .flag = NULL, .val = '1' }, + { .name = "nospoof", .has_arg = 0, .flag = NULL, .val = '2' }, + { .name = NULL } +}; + +static struct xtables_target MAP66_tg6_reg = { + .name = "MAP66", + .version = XTABLES_VERSION, +#if IPTABLES_VERSION_CODE >= IPTABLES_VERSION_CMP(1,4,1) + .family = NFPROTO_IPV6, +#endif + .size = XT_ALIGN(sizeof(struct ip6t_MAP66_info)), + .userspacesize = XT_ALIGN(sizeof(struct ip6t_MAP66_info)), + .help = MAP66_help, + .parse = MAP66_parse, + .final_check = MAP66_check, + .save = MAP66_save, + .extra_opts = MAP66_opts, +}; + +void _init(void) +{ + xtables_register_target(&MAP66_tg6_reg); +} |