1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2006 Patrick McHardy <kaber@trash.net> 4 */ 5 6 #include <linux/module.h> 7 #include <linux/init.h> 8 #include <linux/skbuff.h> 9 10 #include <linux/netfilter/x_tables.h> 11 #include <linux/netfilter/xt_NFLOG.h> 12 #include <net/netfilter/nf_log.h> 13 14 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); 15 MODULE_DESCRIPTION("Xtables: packet logging to netlink using NFLOG"); 16 MODULE_LICENSE("GPL"); 17 MODULE_ALIAS("ipt_NFLOG"); 18 MODULE_ALIAS("ip6t_NFLOG"); 19 20 static unsigned int 21 nflog_tg(struct sk_buff *skb, const struct xt_action_param *par) 22 { 23 const struct xt_nflog_info *info = par->targinfo; 24 struct net *net = xt_net(par); 25 struct nf_loginfo li; 26 27 li.type = NF_LOG_TYPE_ULOG; 28 li.u.ulog.copy_len = info->len; 29 li.u.ulog.group = info->group; 30 li.u.ulog.qthreshold = info->threshold; 31 li.u.ulog.flags = 0; 32 33 if (info->flags & XT_NFLOG_F_COPY_LEN) 34 li.u.ulog.flags |= NF_LOG_F_COPY_LEN; 35 36 nf_log_packet(net, xt_family(par), xt_hooknum(par), skb, xt_in(par), 37 xt_out(par), &li, "%s", info->prefix); 38 39 return XT_CONTINUE; 40 } 41 42 static int nflog_tg_check(const struct xt_tgchk_param *par) 43 { 44 const struct xt_nflog_info *info = par->targinfo; 45 int ret; 46 47 if (info->flags & ~XT_NFLOG_MASK) 48 return -EINVAL; 49 if (info->prefix[sizeof(info->prefix) - 1] != '\0') 50 return -EINVAL; 51 52 ret = nf_logger_find_get(par->family, NF_LOG_TYPE_ULOG); 53 if (ret != 0 && !par->nft_compat) { 54 request_module("%s", "nfnetlink_log"); 55 56 ret = nf_logger_find_get(par->family, NF_LOG_TYPE_ULOG); 57 } 58 59 return ret; 60 } 61 62 static void nflog_tg_destroy(const struct xt_tgdtor_param *par) 63 { 64 nf_logger_put(par->family, NF_LOG_TYPE_ULOG); 65 } 66 67 static struct xt_target nflog_tg_reg __read_mostly = { 68 .name = "NFLOG", 69 .revision = 0, 70 .family = NFPROTO_UNSPEC, 71 .checkentry = nflog_tg_check, 72 .destroy = nflog_tg_destroy, 73 .target = nflog_tg, 74 .targetsize = sizeof(struct xt_nflog_info), 75 .me = THIS_MODULE, 76 }; 77 78 static int __init nflog_tg_init(void) 79 { 80 return xt_register_target(&nflog_tg_reg); 81 } 82 83 static void __exit nflog_tg_exit(void) 84 { 85 xt_unregister_target(&nflog_tg_reg); 86 } 87 88 module_init(nflog_tg_init); 89 module_exit(nflog_tg_exit); 90 MODULE_SOFTDEP("pre: nfnetlink_log"); 91