| 1 | // SPDX-License-Identifier: GPL-2.0-only |
|---|---|
| 2 | /* |
| 3 | * Copyright (c) 2011 Patrick McHardy <kaber@trash.net> |
| 4 | */ |
| 5 | |
| 6 | #include <linux/module.h> |
| 7 | #include <linux/skbuff.h> |
| 8 | #include <linux/netdevice.h> |
| 9 | |
| 10 | #include <linux/netfilter/xt_devgroup.h> |
| 11 | #include <linux/netfilter/x_tables.h> |
| 12 | |
| 13 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |
| 14 | MODULE_LICENSE("GPL"); |
| 15 | MODULE_DESCRIPTION("Xtables: Device group match"); |
| 16 | MODULE_ALIAS("ipt_devgroup"); |
| 17 | MODULE_ALIAS("ip6t_devgroup"); |
| 18 | |
| 19 | static bool devgroup_mt(const struct sk_buff *skb, struct xt_action_param *par) |
| 20 | { |
| 21 | const struct xt_devgroup_info *info = par->matchinfo; |
| 22 | |
| 23 | if (info->flags & XT_DEVGROUP_MATCH_SRC && |
| 24 | (((info->src_group ^ xt_in(par)->group) & info->src_mask ? 1 : 0) ^ |
| 25 | ((info->flags & XT_DEVGROUP_INVERT_SRC) ? 1 : 0))) |
| 26 | return false; |
| 27 | |
| 28 | if (info->flags & XT_DEVGROUP_MATCH_DST && |
| 29 | (((info->dst_group ^ xt_out(par)->group) & info->dst_mask ? 1 : 0) ^ |
| 30 | ((info->flags & XT_DEVGROUP_INVERT_DST) ? 1 : 0))) |
| 31 | return false; |
| 32 | |
| 33 | return true; |
| 34 | } |
| 35 | |
| 36 | static int devgroup_mt_checkentry(const struct xt_mtchk_param *par) |
| 37 | { |
| 38 | const struct xt_devgroup_info *info = par->matchinfo; |
| 39 | |
| 40 | if (info->flags & ~(XT_DEVGROUP_MATCH_SRC | XT_DEVGROUP_INVERT_SRC | |
| 41 | XT_DEVGROUP_MATCH_DST | XT_DEVGROUP_INVERT_DST)) |
| 42 | return -EINVAL; |
| 43 | |
| 44 | if (info->flags & XT_DEVGROUP_MATCH_SRC && |
| 45 | par->hook_mask & ~((1 << NF_INET_PRE_ROUTING) | |
| 46 | (1 << NF_INET_LOCAL_IN) | |
| 47 | (1 << NF_INET_FORWARD))) |
| 48 | return -EINVAL; |
| 49 | |
| 50 | if (info->flags & XT_DEVGROUP_MATCH_DST && |
| 51 | par->hook_mask & ~((1 << NF_INET_FORWARD) | |
| 52 | (1 << NF_INET_LOCAL_OUT) | |
| 53 | (1 << NF_INET_POST_ROUTING))) |
| 54 | return -EINVAL; |
| 55 | |
| 56 | return 0; |
| 57 | } |
| 58 | |
| 59 | static struct xt_match devgroup_mt_reg __read_mostly = { |
| 60 | .name = "devgroup", |
| 61 | .match = devgroup_mt, |
| 62 | .checkentry = devgroup_mt_checkentry, |
| 63 | .matchsize = sizeof(struct xt_devgroup_info), |
| 64 | .family = NFPROTO_UNSPEC, |
| 65 | .me = THIS_MODULE |
| 66 | }; |
| 67 | |
| 68 | static int __init devgroup_mt_init(void) |
| 69 | { |
| 70 | return xt_register_match(target: &devgroup_mt_reg); |
| 71 | } |
| 72 | |
| 73 | static void __exit devgroup_mt_exit(void) |
| 74 | { |
| 75 | xt_unregister_match(target: &devgroup_mt_reg); |
| 76 | } |
| 77 | |
| 78 | module_init(devgroup_mt_init); |
| 79 | module_exit(devgroup_mt_exit); |
| 80 |