projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| edf0e1fb MT |
1 | /* iptables module for the packet checksum mangling |
| 2 | * | |
| 3 | * (C) 2002 by Harald Welte <[email protected]> | |
| 4 | * (C) 2010 Red Hat, Inc. | |
| 5 | * | |
| 6 | * Author: Michael S. Tsirkin <[email protected]> | |
| 7 | * | |
| 8 | * This program is free software; you can redistribute it and/or modify | |
| 9 | * it under the terms of the GNU General Public License version 2 as | |
| 10 | * published by the Free Software Foundation. | |
| 11 | */ | |
| 12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
| 13 | #include <linux/module.h> | |
| 14 | #include <linux/skbuff.h> | |
| 15 | ||
| 16 | #include <linux/netfilter/x_tables.h> | |
| 17 | #include <linux/netfilter/xt_CHECKSUM.h> | |
| 18 | ||
| 19 | MODULE_LICENSE("GPL"); | |
| 20 | MODULE_AUTHOR("Michael S. Tsirkin <[email protected]>"); | |
| 21 | MODULE_DESCRIPTION("Xtables: checksum modification"); | |
| 22 | MODULE_ALIAS("ipt_CHECKSUM"); | |
| 23 | MODULE_ALIAS("ip6t_CHECKSUM"); | |
| 24 | ||
| 25 | static unsigned int | |
| 26 | checksum_tg(struct sk_buff *skb, const struct xt_action_param *par) | |
| 27 | { | |
| 28 | if (skb->ip_summed == CHECKSUM_PARTIAL) | |
| 29 | skb_checksum_help(skb); | |
| 30 | ||
| 31 | return XT_CONTINUE; | |
| 32 | } | |
| 33 | ||
| 34 | static int checksum_tg_check(const struct xt_tgchk_param *par) | |
| 35 | { | |
| 36 | const struct xt_CHECKSUM_info *einfo = par->targinfo; | |
| 37 | ||
| 38 | if (einfo->operation & ~XT_CHECKSUM_OP_FILL) { | |
| 39 | pr_info("unsupported CHECKSUM operation %x\n", einfo->operation); | |
| 40 | return -EINVAL; | |
| 41 | } | |
| 42 | if (!einfo->operation) { | |
| 43 | pr_info("no CHECKSUM operation enabled\n"); | |
| 44 | return -EINVAL; | |
| 45 | } | |
| 46 | return 0; | |
| 47 | } | |
| 48 | ||
| 49 | static struct xt_target checksum_tg_reg __read_mostly = { | |
| 50 | .name = "CHECKSUM", | |
| 51 | .family = NFPROTO_UNSPEC, | |
| 52 | .target = checksum_tg, | |
| 53 | .targetsize = sizeof(struct xt_CHECKSUM_info), | |
| 54 | .table = "mangle", | |
| 55 | .checkentry = checksum_tg_check, | |
| 56 | .me = THIS_MODULE, | |
| 57 | }; | |
| 58 | ||
| 59 | static int __init checksum_tg_init(void) | |
| 60 | { | |
| 61 | return xt_register_target(&checksum_tg_reg); | |
| 62 | } | |
| 63 | ||
| 64 | static void __exit checksum_tg_exit(void) | |
| 65 | { | |
| 66 | xt_unregister_target(&checksum_tg_reg); | |
| 67 | } | |
| 68 | ||
| 69 | module_init(checksum_tg_init); | |
| 70 | module_exit(checksum_tg_exit); |