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netfilter: nf_log_common: merge with nf_log_syslog

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Remove nf_log_common.  Now that all per-af modules have been merged
there is no longer a need to provide a helper module.

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 18:25:10 +01:00 committed by Pablo Neira Ayuso
parent 77ccee96a6
commit e465cccd0b
5 changed files with 181 additions and 258 deletions
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24
include/net/netfilter/nf_log.h
View file

@ -98,28 +98,4 @@ struct nf_log_buf;
struct nf_log_buf *nf_log_buf_open(void);
__printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...);
void nf_log_buf_close(struct nf_log_buf *m);
/* common logging functions */
int nf_log_dump_udp_header(struct nf_log_buf *m, const struct sk_buff *skb,
u8 proto, int fragment, unsigned int offset);
int nf_log_dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb,
u8 proto, int fragment, unsigned int offset,
unsigned int logflags);
void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m,
struct sock *sk);
void nf_log_dump_vlan(struct nf_log_buf *m, const struct sk_buff *skb);
void nf_log_dump_packet_common(struct nf_log_buf *m, 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);
void nf_log_l2packet(struct net *net, u_int8_t pf,
__be16 protocol,
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);
#endif /* _NF_LOG_H */

8
net/netfilter/Kconfig
View file

@ -71,16 +71,13 @@ config NF_CONNTRACK
To compile it as a module, choose M here. If unsure, say N.
config NF_LOG_COMMON
tristate
config NF_LOG_SYSLOG
tristate "Syslog packet logging"
default m if NETFILTER_ADVANCED=n
select NF_LOG_COMMON
help
This option enable support for packet logging via syslog.
It supports IPv4 and common transport protocols such as TCP and UDP.
It supports IPv4, IPV6, ARP and common transport protocols such
as TCP and UDP.
This is a simpler but less flexible logging method compared to
CONFIG_NETFILTER_NETLINK_LOG.
If both are enabled the backend to use can be configured at run-time
@ -930,7 +927,6 @@ config NETFILTER_XT_TARGET_LED
config NETFILTER_XT_TARGET_LOG
tristate "LOG target support"
select NF_LOG_COMMON
select NF_LOG_SYSLOG
select NF_LOG_IPV6 if IP6_NF_IPTABLES
default m if NETFILTER_ADVANCED=n

2
net/netfilter/Makefile
View file

@ -48,8 +48,6 @@ obj-$(CONFIG_NF_CONNTRACK_TFTP) += nf_conntrack_tftp.o
nf_nat-y := nf_nat_core.o nf_nat_proto.o nf_nat_helper.o
# generic transport layer logging
obj-$(CONFIG_NF_LOG_COMMON) += nf_log_common.o
obj-$(CONFIG_NF_LOG_SYSLOG) += nf_log_syslog.o
obj-$(CONFIG_NF_NAT) += nf_nat.o

224
net/netfilter/nf_log_common.c
View file

@ -1,224 +0,0 @@
// SPDX-License-Identifier: GPL-2.0-only
/* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
*/
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/ip.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/tcp.h>
#include <net/route.h>
#include <linux/netfilter.h>
#include <linux/netfilter_bridge.h>
#include <linux/netfilter/xt_LOG.h>
#include <net/netfilter/nf_log.h>
int nf_log_dump_udp_header(struct nf_log_buf *m, const struct sk_buff *skb,
u8 proto, int fragment, unsigned int offset)
{
struct udphdr _udph;
const struct udphdr *uh;
if (proto == IPPROTO_UDP)
/* Max length: 10 "PROTO=UDP " */
nf_log_buf_add(m, "PROTO=UDP ");
else /* Max length: 14 "PROTO=UDPLITE " */
nf_log_buf_add(m, "PROTO=UDPLITE ");
if (fragment)
goto out;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
if (uh == NULL) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
return 1;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
nf_log_buf_add(m, "SPT=%u DPT=%u LEN=%u ",
ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len));
out:
return 0;
}
EXPORT_SYMBOL_GPL(nf_log_dump_udp_header);
int nf_log_dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb,
u8 proto, int fragment, unsigned int offset,
unsigned int logflags)
{
struct tcphdr _tcph;
const struct tcphdr *th;
/* Max length: 10 "PROTO=TCP " */
nf_log_buf_add(m, "PROTO=TCP ");
if (fragment)
return 0;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
if (th == NULL) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
return 1;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
nf_log_buf_add(m, "SPT=%u DPT=%u ",
ntohs(th->source), ntohs(th->dest));
/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
if (logflags & NF_LOG_TCPSEQ) {
nf_log_buf_add(m, "SEQ=%u ACK=%u ",
ntohl(th->seq), ntohl(th->ack_seq));
}
/* Max length: 13 "WINDOW=65535 " */
nf_log_buf_add(m, "WINDOW=%u ", ntohs(th->window));
/* Max length: 9 "RES=0x3C " */
nf_log_buf_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) &
TCP_RESERVED_BITS) >> 22));
/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
if (th->cwr)
nf_log_buf_add(m, "CWR ");
if (th->ece)
nf_log_buf_add(m, "ECE ");
if (th->urg)
nf_log_buf_add(m, "URG ");
if (th->ack)
nf_log_buf_add(m, "ACK ");
if (th->psh)
nf_log_buf_add(m, "PSH ");
if (th->rst)
nf_log_buf_add(m, "RST ");
if (th->syn)
nf_log_buf_add(m, "SYN ");
if (th->fin)
nf_log_buf_add(m, "FIN ");
/* Max length: 11 "URGP=65535 " */
nf_log_buf_add(m, "URGP=%u ", ntohs(th->urg_ptr));
if ((logflags & NF_LOG_TCPOPT) && th->doff*4 > sizeof(struct tcphdr)) {
u_int8_t _opt[60 - sizeof(struct tcphdr)];
const u_int8_t *op;
unsigned int i;
unsigned int optsize = th->doff*4 - sizeof(struct tcphdr);
op = skb_header_pointer(skb, offset + sizeof(struct tcphdr),
optsize, _opt);
if (op == NULL) {
nf_log_buf_add(m, "OPT (TRUNCATED)");
return 1;
}
/* Max length: 127 "OPT (" 15*4*2chars ") " */
nf_log_buf_add(m, "OPT (");
for (i = 0; i < optsize; i++)
nf_log_buf_add(m, "%02X", op[i]);
nf_log_buf_add(m, ") ");
}
return 0;
}
EXPORT_SYMBOL_GPL(nf_log_dump_tcp_header);
void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m,
struct sock *sk)
{
if (!sk || !sk_fullsock(sk) || !net_eq(net, sock_net(sk)))
return;
read_lock_bh(&sk->sk_callback_lock);
if (sk->sk_socket && sk->sk_socket->file) {
const struct cred *cred = sk->sk_socket->file->f_cred;
nf_log_buf_add(m, "UID=%u GID=%u ",
from_kuid_munged(&init_user_ns, cred->fsuid),
from_kgid_munged(&init_user_ns, cred->fsgid));
}
read_unlock_bh(&sk->sk_callback_lock);
}
EXPORT_SYMBOL_GPL(nf_log_dump_sk_uid_gid);
void
nf_log_dump_packet_common(struct nf_log_buf *m, 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)
{
const struct net_device *physoutdev __maybe_unused;
const struct net_device *physindev __maybe_unused;
nf_log_buf_add(m, KERN_SOH "%c%sIN=%s OUT=%s ",
'0' + loginfo->u.log.level, prefix,
in ? in->name : "",
out ? out->name : "");
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
physindev = nf_bridge_get_physindev(skb);
if (physindev && in != physindev)
nf_log_buf_add(m, "PHYSIN=%s ", physindev->name);
physoutdev = nf_bridge_get_physoutdev(skb);
if (physoutdev && out != physoutdev)
nf_log_buf_add(m, "PHYSOUT=%s ", physoutdev->name);
#endif
}
EXPORT_SYMBOL_GPL(nf_log_dump_packet_common);
void nf_log_dump_vlan(struct nf_log_buf *m, const struct sk_buff *skb)
{
u16 vid;
if (!skb_vlan_tag_present(skb))
return;
vid = skb_vlan_tag_get(skb);
nf_log_buf_add(m, "VPROTO=%04x VID=%u ", ntohs(skb->vlan_proto), vid);
}
EXPORT_SYMBOL_GPL(nf_log_dump_vlan);
/* bridge and netdev logging families share this code. */
void nf_log_l2packet(struct net *net, u_int8_t pf,
__be16 protocol,
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)
{
switch (protocol) {
case htons(ETH_P_IP):
nf_log_packet(net, NFPROTO_IPV4, hooknum, skb, in, out,
loginfo, "%s", prefix);
break;
case htons(ETH_P_IPV6):
nf_log_packet(net, NFPROTO_IPV6, hooknum, skb, in, out,
loginfo, "%s", prefix);
break;
case htons(ETH_P_ARP):
case htons(ETH_P_RARP):
nf_log_packet(net, NFPROTO_ARP, hooknum, skb, in, out,
loginfo, "%s", prefix);
break;
}
}
EXPORT_SYMBOL_GPL(nf_log_l2packet);
static int __init nf_log_common_init(void)
{
return 0;
}
static void __exit nf_log_common_exit(void) {}
module_init(nf_log_common_init);
module_exit(nf_log_common_exit);
MODULE_LICENSE("GPL");

181
net/netfilter/nf_log_syslog.c
View file

@ -18,6 +18,7 @@
#include <net/route.h>
#include <linux/netfilter.h>
#include <linux/netfilter_bridge.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter/xt_LOG.h>
#include <net/netfilter/nf_log.h>
@ -39,6 +40,16 @@ struct arppayload {
unsigned char ip_dst[4];
};
static void nf_log_dump_vlan(struct nf_log_buf *m, const struct sk_buff *skb)
{
u16 vid;
if (!skb_vlan_tag_present(skb))
return;
vid = skb_vlan_tag_get(skb);
nf_log_buf_add(m, "VPROTO=%04x VID=%u ", ntohs(skb->vlan_proto), vid);
}
static void noinline_for_stack
dump_arp_packet(struct nf_log_buf *m,
const struct nf_loginfo *info,
@ -89,6 +100,30 @@ dump_arp_packet(struct nf_log_buf *m,
ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst);
}
static void
nf_log_dump_packet_common(struct nf_log_buf *m, u8 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)
{
const struct net_device *physoutdev __maybe_unused;
const struct net_device *physindev __maybe_unused;
nf_log_buf_add(m, KERN_SOH "%c%sIN=%s OUT=%s ",
'0' + loginfo->u.log.level, prefix,
in ? in->name : "",
out ? out->name : "");
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
physindev = nf_bridge_get_physindev(skb);
if (physindev && in != physindev)
nf_log_buf_add(m, "PHYSIN=%s ", physindev->name);
physoutdev = nf_bridge_get_physoutdev(skb);
if (physoutdev && out != physoutdev)
nf_log_buf_add(m, "PHYSOUT=%s ", physoutdev->name);
#endif
}
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,
@ -121,6 +156,138 @@ static struct nf_logger nf_arp_logger __read_mostly = {
.me = THIS_MODULE,
};
static void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m,
struct sock *sk)
{
if (!sk || !sk_fullsock(sk) || !net_eq(net, sock_net(sk)))
return;
read_lock_bh(&sk->sk_callback_lock);
if (sk->sk_socket && sk->sk_socket->file) {
const struct cred *cred = sk->sk_socket->file->f_cred;
nf_log_buf_add(m, "UID=%u GID=%u ",
from_kuid_munged(&init_user_ns, cred->fsuid),
from_kgid_munged(&init_user_ns, cred->fsgid));
}
read_unlock_bh(&sk->sk_callback_lock);
}
static noinline_for_stack int
nf_log_dump_tcp_header(struct nf_log_buf *m,
const struct sk_buff *skb,
u8 proto, int fragment,
unsigned int offset,
unsigned int logflags)
{
struct tcphdr _tcph;
const struct tcphdr *th;
/* Max length: 10 "PROTO=TCP " */
nf_log_buf_add(m, "PROTO=TCP ");
if (fragment)
return 0;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
if (!th) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
return 1;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
nf_log_buf_add(m, "SPT=%u DPT=%u ",
ntohs(th->source), ntohs(th->dest));
/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
if (logflags & NF_LOG_TCPSEQ) {
nf_log_buf_add(m, "SEQ=%u ACK=%u ",
ntohl(th->seq), ntohl(th->ack_seq));
}
/* Max length: 13 "WINDOW=65535 " */
nf_log_buf_add(m, "WINDOW=%u ", ntohs(th->window));
/* Max length: 9 "RES=0x3C " */
nf_log_buf_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) &
TCP_RESERVED_BITS) >> 22));
/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
if (th->cwr)
nf_log_buf_add(m, "CWR ");
if (th->ece)
nf_log_buf_add(m, "ECE ");
if (th->urg)
nf_log_buf_add(m, "URG ");
if (th->ack)
nf_log_buf_add(m, "ACK ");
if (th->psh)
nf_log_buf_add(m, "PSH ");
if (th->rst)
nf_log_buf_add(m, "RST ");
if (th->syn)
nf_log_buf_add(m, "SYN ");
if (th->fin)
nf_log_buf_add(m, "FIN ");
/* Max length: 11 "URGP=65535 " */
nf_log_buf_add(m, "URGP=%u ", ntohs(th->urg_ptr));
if ((logflags & NF_LOG_TCPOPT) && th->doff * 4 > sizeof(struct tcphdr)) {
unsigned int optsize = th->doff * 4 - sizeof(struct tcphdr);
u8 _opt[60 - sizeof(struct tcphdr)];
unsigned int i;
const u8 *op;
op = skb_header_pointer(skb, offset + sizeof(struct tcphdr),
optsize, _opt);
if (!op) {
nf_log_buf_add(m, "OPT (TRUNCATED)");
return 1;
}
/* Max length: 127 "OPT (" 15*4*2chars ") " */
nf_log_buf_add(m, "OPT (");
for (i = 0; i < optsize; i++)
nf_log_buf_add(m, "%02X", op[i]);
nf_log_buf_add(m, ") ");
}
return 0;
}
static noinline_for_stack int
nf_log_dump_udp_header(struct nf_log_buf *m,
const struct sk_buff *skb,
u8 proto, int fragment,
unsigned int offset)
{
struct udphdr _udph;
const struct udphdr *uh;
if (proto == IPPROTO_UDP)
/* Max length: 10 "PROTO=UDP " */
nf_log_buf_add(m, "PROTO=UDP ");
else /* Max length: 14 "PROTO=UDPLITE " */
nf_log_buf_add(m, "PROTO=UDPLITE ");
if (fragment)
goto out;
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
if (!uh) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
return 1;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
nf_log_buf_add(m, "SPT=%u DPT=%u LEN=%u ",
ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len));
out:
return 0;
}
/* One level of recursion won't kill us */
static noinline_for_stack void
dump_ipv4_packet(struct net *net, struct nf_log_buf *m,
@ -776,8 +943,18 @@ static void nf_log_netdev_packet(struct net *net, u_int8_t pf,
const struct nf_loginfo *loginfo,
const char *prefix)
{
nf_log_l2packet(net, pf, skb->protocol, hooknum, skb, in, out,
loginfo, prefix);
switch (skb->protocol) {
case htons(ETH_P_IP):
nf_log_ip_packet(net, pf, hooknum, skb, in, out, loginfo, prefix);
break;
case htons(ETH_P_IPV6):
nf_log_ip6_packet(net, pf, hooknum, skb, in, out, loginfo, prefix);
break;
case htons(ETH_P_ARP):
case htons(ETH_P_RARP):
nf_log_arp_packet(net, pf, hooknum, skb, in, out, loginfo, prefix);
break;
}
}
static struct nf_logger nf_netdev_logger __read_mostly = {