1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * This is a module which is used for logging packets. |
4 | */ |
5 | |
6 | /* (C) 1999-2001 Paul `Rusty' Russell |
7 | * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> |
8 | */ |
9 | |
10 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
11 | #include <linux/module.h> |
12 | #include <linux/spinlock.h> |
13 | #include <linux/skbuff.h> |
14 | #include <linux/if_arp.h> |
15 | #include <linux/ip.h> |
16 | #include <net/ipv6.h> |
17 | #include <net/icmp.h> |
18 | #include <net/udp.h> |
19 | #include <net/tcp.h> |
20 | #include <net/route.h> |
21 | |
22 | #include <linux/netfilter.h> |
23 | #include <linux/netfilter/x_tables.h> |
24 | #include <linux/netfilter/xt_LOG.h> |
25 | #include <linux/netfilter_ipv6/ip6_tables.h> |
26 | #include <net/netfilter/nf_log.h> |
27 | |
28 | static unsigned int |
29 | log_tg(struct sk_buff *skb, const struct xt_action_param *par) |
30 | { |
31 | const struct xt_log_info *loginfo = par->targinfo; |
32 | struct net *net = xt_net(par); |
33 | struct nf_loginfo li; |
34 | |
35 | li.type = NF_LOG_TYPE_LOG; |
36 | li.u.log.level = loginfo->level; |
37 | li.u.log.logflags = loginfo->logflags; |
38 | |
39 | nf_log_packet(net, pf: xt_family(par), hooknum: xt_hooknum(par), skb, in: xt_in(par), |
40 | out: xt_out(par), li: &li, fmt: "%s" , loginfo->prefix); |
41 | return XT_CONTINUE; |
42 | } |
43 | |
44 | static int log_tg_check(const struct xt_tgchk_param *par) |
45 | { |
46 | const struct xt_log_info *loginfo = par->targinfo; |
47 | int ret; |
48 | |
49 | if (par->family != NFPROTO_IPV4 && par->family != NFPROTO_IPV6) |
50 | return -EINVAL; |
51 | |
52 | if (loginfo->level >= 8) { |
53 | pr_debug("level %u >= 8\n" , loginfo->level); |
54 | return -EINVAL; |
55 | } |
56 | |
57 | if (loginfo->prefix[sizeof(loginfo->prefix)-1] != '\0') { |
58 | pr_debug("prefix is not null-terminated\n" ); |
59 | return -EINVAL; |
60 | } |
61 | |
62 | ret = nf_logger_find_get(pf: par->family, type: NF_LOG_TYPE_LOG); |
63 | if (ret != 0 && !par->nft_compat) { |
64 | request_module("%s" , "nf_log_syslog" ); |
65 | |
66 | ret = nf_logger_find_get(pf: par->family, type: NF_LOG_TYPE_LOG); |
67 | } |
68 | |
69 | return ret; |
70 | } |
71 | |
72 | static void log_tg_destroy(const struct xt_tgdtor_param *par) |
73 | { |
74 | nf_logger_put(pf: par->family, type: NF_LOG_TYPE_LOG); |
75 | } |
76 | |
77 | static struct xt_target log_tg_regs[] __read_mostly = { |
78 | { |
79 | .name = "LOG" , |
80 | .family = NFPROTO_IPV4, |
81 | .target = log_tg, |
82 | .targetsize = sizeof(struct xt_log_info), |
83 | .checkentry = log_tg_check, |
84 | .destroy = log_tg_destroy, |
85 | .me = THIS_MODULE, |
86 | }, |
87 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
88 | { |
89 | .name = "LOG" , |
90 | .family = NFPROTO_IPV6, |
91 | .target = log_tg, |
92 | .targetsize = sizeof(struct xt_log_info), |
93 | .checkentry = log_tg_check, |
94 | .destroy = log_tg_destroy, |
95 | .me = THIS_MODULE, |
96 | }, |
97 | #endif |
98 | }; |
99 | |
100 | static int __init log_tg_init(void) |
101 | { |
102 | return xt_register_targets(target: log_tg_regs, ARRAY_SIZE(log_tg_regs)); |
103 | } |
104 | |
105 | static void __exit log_tg_exit(void) |
106 | { |
107 | xt_unregister_targets(target: log_tg_regs, ARRAY_SIZE(log_tg_regs)); |
108 | } |
109 | |
110 | module_init(log_tg_init); |
111 | module_exit(log_tg_exit); |
112 | |
113 | MODULE_LICENSE("GPL" ); |
114 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>" ); |
115 | MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>" ); |
116 | MODULE_DESCRIPTION("Xtables: IPv4/IPv6 packet logging" ); |
117 | MODULE_ALIAS("ipt_LOG" ); |
118 | MODULE_ALIAS("ip6t_LOG" ); |
119 | MODULE_SOFTDEP("pre: nf_log_syslog" ); |
120 | |