netfilter: nf_log_arp: merge with nf_log_syslog

similar to previous change: nf_log_syslog now covers ARP logging
as well, the old nf_log_arp module is removed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2021-03-25 18:25:06 +01:00 committed by Pablo Neira Ayuso
parent db3187ae21
commit f11d61e795
4 changed files with 115 additions and 178 deletions

View File

@ -76,7 +76,10 @@ config NF_DUP_IPV4
config NF_LOG_ARP
tristate "ARP packet logging"
default m if NETFILTER_ADVANCED=n
select NF_LOG_COMMON
select NF_LOG_SYSLOG
help
This is a backwards-compat option for the user's convenience
(e.g. when running oldconfig). It selects CONFIG_NF_LOG_SYSLOG.
config NF_LOG_IPV4
tristate "IPv4 packet logging"

View File

@ -9,9 +9,6 @@ obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o
obj-$(CONFIG_NF_SOCKET_IPV4) += nf_socket_ipv4.o
obj-$(CONFIG_NF_TPROXY_IPV4) += nf_tproxy_ipv4.o
# logging
obj-$(CONFIG_NF_LOG_ARP) += nf_log_arp.o
# reject
obj-$(CONFIG_NF_REJECT_IPV4) += nf_reject_ipv4.o

View File

@ -1,172 +0,0 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* (C) 2014 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* Based on code from ebt_log from:
*
* Bart De Schuymer <bdschuym@pandora.be>
* Harald Welte <laforge@netfilter.org>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/ip.h>
#include <net/route.h>
#include <linux/netfilter.h>
#include <linux/netfilter/xt_LOG.h>
#include <net/netfilter/nf_log.h>
static const struct nf_loginfo default_loginfo = {
.type = NF_LOG_TYPE_LOG,
.u = {
.log = {
.level = LOGLEVEL_NOTICE,
.logflags = NF_LOG_DEFAULT_MASK,
},
},
};
struct arppayload {
unsigned char mac_src[ETH_ALEN];
unsigned char ip_src[4];
unsigned char mac_dst[ETH_ALEN];
unsigned char ip_dst[4];
};
static void dump_arp_packet(struct nf_log_buf *m,
const struct nf_loginfo *info,
const struct sk_buff *skb, unsigned int nhoff)
{
const struct arppayload *ap;
struct arppayload _arpp;
const struct arphdr *ah;
unsigned int logflags;
struct arphdr _arph;
ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
if (ah == NULL) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
else
logflags = NF_LOG_DEFAULT_MASK;
if (logflags & NF_LOG_MACDECODE) {
nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM ",
eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest);
nf_log_dump_vlan(m, skb);
nf_log_buf_add(m, "MACPROTO=%04x ",
ntohs(eth_hdr(skb)->h_proto));
}
nf_log_buf_add(m, "ARP HTYPE=%d PTYPE=0x%04x OPCODE=%d",
ntohs(ah->ar_hrd), ntohs(ah->ar_pro), ntohs(ah->ar_op));
/* If it's for Ethernet and the lengths are OK, then log the ARP
* payload.
*/
if (ah->ar_hrd != htons(ARPHRD_ETHER) ||
ah->ar_hln != ETH_ALEN ||
ah->ar_pln != sizeof(__be32))
return;
ap = skb_header_pointer(skb, sizeof(_arph), sizeof(_arpp), &_arpp);
if (ap == NULL) {
nf_log_buf_add(m, " INCOMPLETE [%zu bytes]",
skb->len - sizeof(_arph));
return;
}
nf_log_buf_add(m, " MACSRC=%pM IPSRC=%pI4 MACDST=%pM IPDST=%pI4",
ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst);
}
static void nf_log_arp_packet(struct net *net, u_int8_t pf,
unsigned int hooknum, const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo,
const char *prefix)
{
struct nf_log_buf *m;
/* FIXME: Disabled from containers until syslog ns is supported */
if (!net_eq(net, &init_net) && !sysctl_nf_log_all_netns)
return;
m = nf_log_buf_open();
if (!loginfo)
loginfo = &default_loginfo;
nf_log_dump_packet_common(m, pf, hooknum, skb, in, out, loginfo,
prefix);
dump_arp_packet(m, loginfo, skb, 0);
nf_log_buf_close(m);
}
static struct nf_logger nf_arp_logger __read_mostly = {
.name = "nf_log_arp",
.type = NF_LOG_TYPE_LOG,
.logfn = nf_log_arp_packet,
.me = THIS_MODULE,
};
static int __net_init nf_log_arp_net_init(struct net *net)
{
return nf_log_set(net, NFPROTO_ARP, &nf_arp_logger);
}
static void __net_exit nf_log_arp_net_exit(struct net *net)
{
nf_log_unset(net, &nf_arp_logger);
}
static struct pernet_operations nf_log_arp_net_ops = {
.init = nf_log_arp_net_init,
.exit = nf_log_arp_net_exit,
};
static int __init nf_log_arp_init(void)
{
int ret;
ret = register_pernet_subsys(&nf_log_arp_net_ops);
if (ret < 0)
return ret;
ret = nf_log_register(NFPROTO_ARP, &nf_arp_logger);
if (ret < 0) {
pr_err("failed to register logger\n");
goto err1;
}
return 0;
err1:
unregister_pernet_subsys(&nf_log_arp_net_ops);
return ret;
}
static void __exit nf_log_arp_exit(void)
{
unregister_pernet_subsys(&nf_log_arp_net_ops);
nf_log_unregister(&nf_arp_logger);
}
module_init(nf_log_arp_init);
module_exit(nf_log_arp_exit);
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
MODULE_DESCRIPTION("Netfilter ARP packet logging");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NF_LOGGER(3, 0);

View File

@ -31,6 +31,95 @@ static const struct nf_loginfo default_loginfo = {
},
};
struct arppayload {
unsigned char mac_src[ETH_ALEN];
unsigned char ip_src[4];
unsigned char mac_dst[ETH_ALEN];
unsigned char ip_dst[4];
};
static void noinline_for_stack
dump_arp_packet(struct nf_log_buf *m,
const struct nf_loginfo *info,
const struct sk_buff *skb, unsigned int nhoff)
{
const struct arppayload *ap;
struct arppayload _arpp;
const struct arphdr *ah;
unsigned int logflags;
struct arphdr _arph;
ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
if (!ah) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
else
logflags = NF_LOG_DEFAULT_MASK;
if (logflags & NF_LOG_MACDECODE) {
nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM ",
eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest);
nf_log_dump_vlan(m, skb);
nf_log_buf_add(m, "MACPROTO=%04x ",
ntohs(eth_hdr(skb)->h_proto));
}
nf_log_buf_add(m, "ARP HTYPE=%d PTYPE=0x%04x OPCODE=%d",
ntohs(ah->ar_hrd), ntohs(ah->ar_pro), ntohs(ah->ar_op));
/* If it's for Ethernet and the lengths are OK, then log the ARP
* payload.
*/
if (ah->ar_hrd != htons(ARPHRD_ETHER) ||
ah->ar_hln != ETH_ALEN ||
ah->ar_pln != sizeof(__be32))
return;
ap = skb_header_pointer(skb, sizeof(_arph), sizeof(_arpp), &_arpp);
if (!ap) {
nf_log_buf_add(m, " INCOMPLETE [%zu bytes]",
skb->len - sizeof(_arph));
return;
}
nf_log_buf_add(m, " MACSRC=%pM IPSRC=%pI4 MACDST=%pM IPDST=%pI4",
ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst);
}
static void nf_log_arp_packet(struct net *net, u_int8_t pf,
unsigned int hooknum, const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct nf_loginfo *loginfo,
const char *prefix)
{
struct nf_log_buf *m;
/* FIXME: Disabled from containers until syslog ns is supported */
if (!net_eq(net, &init_net) && !sysctl_nf_log_all_netns)
return;
m = nf_log_buf_open();
if (!loginfo)
loginfo = &default_loginfo;
nf_log_dump_packet_common(m, pf, hooknum, skb, in, out, loginfo,
prefix);
dump_arp_packet(m, loginfo, skb, 0);
nf_log_buf_close(m);
}
static struct nf_logger nf_arp_logger __read_mostly = {
.name = "nf_log_arp",
.type = NF_LOG_TYPE_LOG,
.logfn = nf_log_arp_packet,
.me = THIS_MODULE,
};
/* One level of recursion won't kill us */
static noinline_for_stack void
dump_ipv4_packet(struct net *net, struct nf_log_buf *m,
@ -343,12 +432,23 @@ static struct nf_logger nf_ip_logger __read_mostly = {
static int __net_init nf_log_syslog_net_init(struct net *net)
{
return nf_log_set(net, NFPROTO_IPV4, &nf_ip_logger);
int ret = nf_log_set(net, NFPROTO_IPV4, &nf_ip_logger);
if (ret)
return ret;
ret = nf_log_set(net, NFPROTO_ARP, &nf_arp_logger);
if (ret)
goto err1;
err1:
nf_log_unset(net, &nf_arp_logger);
return ret;
}
static void __net_exit nf_log_syslog_net_exit(struct net *net)
{
nf_log_unset(net, &nf_ip_logger);
nf_log_unset(net, &nf_arp_logger);
}
static struct pernet_operations nf_log_syslog_net_ops = {
@ -368,9 +468,15 @@ static int __init nf_log_syslog_init(void)
if (ret < 0)
goto err1;
return 0;
ret = nf_log_register(NFPROTO_ARP, &nf_arp_logger);
if (ret < 0)
goto err2;
return 0;
err2:
nf_log_unregister(&nf_arp_logger);
err1:
pr_err("failed to register logger\n");
unregister_pernet_subsys(&nf_log_syslog_net_ops);
return ret;
}
@ -379,6 +485,7 @@ static void __exit nf_log_syslog_exit(void)
{
unregister_pernet_subsys(&nf_log_syslog_net_ops);
nf_log_unregister(&nf_ip_logger);
nf_log_unregister(&nf_arp_logger);
}
module_init(nf_log_syslog_init);
@ -387,5 +494,7 @@ module_exit(nf_log_syslog_exit);
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
MODULE_DESCRIPTION("Netfilter syslog packet logging");
MODULE_LICENSE("GPL");
MODULE_ALIAS("nf_log_arp");
MODULE_ALIAS("nf_log_ipv4");
MODULE_ALIAS_NF_LOGGER(AF_INET, 0);
MODULE_ALIAS_NF_LOGGER(3, 0);