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(&devgroup_mt_reg); 71 } 72 73 static void __exit devgroup_mt_exit(void) 74 { 75 xt_unregister_match(&devgroup_mt_reg); 76 } 77 78 module_init(devgroup_mt_init); 79 module_exit(devgroup_mt_exit); 80