Commit 7200135b authored by Pablo Neira Ayuso's avatar Pablo Neira Ayuso

netfilter: kill ulog targets

This has been marked as deprecated for quite some time and the NFLOG
target replacement has been also available since 2006.
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 9500507c
......@@ -14,6 +14,5 @@ header-y += ebt_nflog.h
header-y += ebt_pkttype.h
header-y += ebt_redirect.h
header-y += ebt_stp.h
header-y += ebt_ulog.h
header-y += ebt_vlan.h
header-y += ebtables.h
#ifndef _EBT_ULOG_H
#define _EBT_ULOG_H
#include <linux/types.h>
#define EBT_ULOG_DEFAULT_NLGROUP 0
#define EBT_ULOG_DEFAULT_QTHRESHOLD 1
#define EBT_ULOG_MAXNLGROUPS 32 /* hardcoded netlink max */
#define EBT_ULOG_PREFIX_LEN 32
#define EBT_ULOG_MAX_QLEN 50
#define EBT_ULOG_WATCHER "ulog"
#define EBT_ULOG_VERSION 1
struct ebt_ulog_info {
__u32 nlgroup;
unsigned int cprange;
unsigned int qthreshold;
char prefix[EBT_ULOG_PREFIX_LEN];
};
typedef struct ebt_ulog_packet_msg {
int version;
char indev[IFNAMSIZ];
char outdev[IFNAMSIZ];
char physindev[IFNAMSIZ];
char physoutdev[IFNAMSIZ];
char prefix[EBT_ULOG_PREFIX_LEN];
struct timeval stamp;
unsigned long mark;
unsigned int hook;
size_t data_len;
/* The complete packet, including Ethernet header and perhaps
* the VLAN header is appended */
unsigned char data[0] __attribute__
((aligned (__alignof__(struct ebt_ulog_info))));
} ebt_ulog_packet_msg_t;
#endif /* _EBT_ULOG_H */
......@@ -5,7 +5,6 @@ header-y += ipt_ECN.h
header-y += ipt_LOG.h
header-y += ipt_REJECT.h
header-y += ipt_TTL.h
header-y += ipt_ULOG.h
header-y += ipt_ah.h
header-y += ipt_ecn.h
header-y += ipt_ttl.h
/* Header file for IP tables userspace logging, Version 1.8
*
* (C) 2000-2002 by Harald Welte <laforge@gnumonks.org>
*
* Distributed under the terms of GNU GPL */
#ifndef _IPT_ULOG_H
#define _IPT_ULOG_H
#ifndef NETLINK_NFLOG
#define NETLINK_NFLOG 5
#endif
#define ULOG_DEFAULT_NLGROUP 1
#define ULOG_DEFAULT_QTHRESHOLD 1
#define ULOG_MAC_LEN 80
#define ULOG_PREFIX_LEN 32
#define ULOG_MAX_QLEN 50
/* Why 50? Well... there is a limit imposed by the slab cache 131000
* bytes. So the multipart netlink-message has to be < 131000 bytes.
* Assuming a standard ethernet-mtu of 1500, we could define this up
* to 80... but even 50 seems to be big enough. */
/* private data structure for each rule with a ULOG target */
struct ipt_ulog_info {
unsigned int nl_group;
size_t copy_range;
size_t qthreshold;
char prefix[ULOG_PREFIX_LEN];
};
/* Format of the ULOG packets passed through netlink */
typedef struct ulog_packet_msg {
unsigned long mark;
long timestamp_sec;
long timestamp_usec;
unsigned int hook;
char indev_name[IFNAMSIZ];
char outdev_name[IFNAMSIZ];
size_t data_len;
char prefix[ULOG_PREFIX_LEN];
unsigned char mac_len;
unsigned char mac[ULOG_MAC_LEN];
unsigned char payload[0];
} ulog_packet_msg_t;
#endif /*_IPT_ULOG_H*/
......@@ -202,22 +202,6 @@ config BRIDGE_EBT_LOG
To compile it as a module, choose M here. If unsure, say N.
config BRIDGE_EBT_ULOG
tristate "ebt: ulog support (OBSOLETE)"
help
This option enables the old bridge-specific "ebt_ulog" implementation
which has been obsoleted by the new "nfnetlink_log" code (see
CONFIG_NETFILTER_NETLINK_LOG).
This option adds the ulog watcher, that you can use in any rule
in any ebtables table. The packet is passed to a userspace
logging daemon using netlink multicast sockets. This differs
from the log watcher in the sense that the complete packet is
sent to userspace instead of a descriptive text and that
netlink multicast sockets are used instead of the syslog.
To compile it as a module, choose M here. If unsure, say N.
config BRIDGE_EBT_NFLOG
tristate "ebt: nflog support"
help
......
/*
* netfilter module for userspace bridged Ethernet frames logging daemons
*
* Authors:
* Bart De Schuymer <bdschuym@pandora.be>
* Harald Welte <laforge@netfilter.org>
*
* November, 2004
*
* Based on ipt_ULOG.c, which is
* (C) 2000-2002 by Harald Welte <laforge@netfilter.org>
*
* This module accepts two parameters:
*
* nlbufsiz:
* The parameter specifies how big the buffer for each netlink multicast
* group is. e.g. If you say nlbufsiz=8192, up to eight kb of packets will
* get accumulated in the kernel until they are sent to userspace. It is
* NOT possible to allocate more than 128kB, and it is strongly discouraged,
* because atomically allocating 128kB inside the network rx softirq is not
* reliable. Please also keep in mind that this buffer size is allocated for
* each nlgroup you are using, so the total kernel memory usage increases
* by that factor.
*
* flushtimeout:
* Specify, after how many hundredths of a second the queue should be
* flushed even if it is not full yet.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/socket.h>
#include <linux/skbuff.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <net/netlink.h>
#include <linux/netdevice.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_ulog.h>
#include <net/netfilter/nf_log.h>
#include <net/netns/generic.h>
#include <net/sock.h>
#include "../br_private.h"
static unsigned int nlbufsiz = NLMSG_GOODSIZE;
module_param(nlbufsiz, uint, 0600);
MODULE_PARM_DESC(nlbufsiz, "netlink buffer size (number of bytes) "
"(defaults to 4096)");
static unsigned int flushtimeout = 10;
module_param(flushtimeout, uint, 0600);
MODULE_PARM_DESC(flushtimeout, "buffer flush timeout (hundredths ofa second) "
"(defaults to 10)");
typedef struct {
unsigned int qlen; /* number of nlmsgs' in the skb */
struct nlmsghdr *lastnlh; /* netlink header of last msg in skb */
struct sk_buff *skb; /* the pre-allocated skb */
struct timer_list timer; /* the timer function */
spinlock_t lock; /* the per-queue lock */
} ebt_ulog_buff_t;
static int ebt_ulog_net_id __read_mostly;
struct ebt_ulog_net {
unsigned int nlgroup[EBT_ULOG_MAXNLGROUPS];
ebt_ulog_buff_t ulog_buffers[EBT_ULOG_MAXNLGROUPS];
struct sock *ebtulognl;
};
static struct ebt_ulog_net *ebt_ulog_pernet(struct net *net)
{
return net_generic(net, ebt_ulog_net_id);
}
/* send one ulog_buff_t to userspace */
static void ulog_send(struct ebt_ulog_net *ebt, unsigned int nlgroup)
{
ebt_ulog_buff_t *ub = &ebt->ulog_buffers[nlgroup];
del_timer(&ub->timer);
if (!ub->skb)
return;
/* last nlmsg needs NLMSG_DONE */
if (ub->qlen > 1)
ub->lastnlh->nlmsg_type = NLMSG_DONE;
NETLINK_CB(ub->skb).dst_group = nlgroup + 1;
netlink_broadcast(ebt->ebtulognl, ub->skb, 0, nlgroup + 1, GFP_ATOMIC);
ub->qlen = 0;
ub->skb = NULL;
}
/* timer function to flush queue in flushtimeout time */
static void ulog_timer(unsigned long data)
{
struct ebt_ulog_net *ebt = container_of((void *)data,
struct ebt_ulog_net,
nlgroup[*(unsigned int *)data]);
ebt_ulog_buff_t *ub = &ebt->ulog_buffers[*(unsigned int *)data];
spin_lock_bh(&ub->lock);
if (ub->skb)
ulog_send(ebt, *(unsigned int *)data);
spin_unlock_bh(&ub->lock);
}
static struct sk_buff *ulog_alloc_skb(unsigned int size)
{
struct sk_buff *skb;
unsigned int n;
n = max(size, nlbufsiz);
skb = alloc_skb(n, GFP_ATOMIC | __GFP_NOWARN);
if (!skb) {
if (n > size) {
/* try to allocate only as much as we need for
* current packet */
skb = alloc_skb(size, GFP_ATOMIC);
if (!skb)
pr_debug("cannot even allocate buffer of size %ub\n",
size);
}
}
return skb;
}
static void ebt_ulog_packet(struct net *net, unsigned int hooknr,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct ebt_ulog_info *uloginfo,
const char *prefix)
{
ebt_ulog_packet_msg_t *pm;
size_t size, copy_len;
struct nlmsghdr *nlh;
struct ebt_ulog_net *ebt = ebt_ulog_pernet(net);
unsigned int group = uloginfo->nlgroup;
ebt_ulog_buff_t *ub = &ebt->ulog_buffers[group];
spinlock_t *lock = &ub->lock;
ktime_t kt;
if ((uloginfo->cprange == 0) ||
(uloginfo->cprange > skb->len + ETH_HLEN))
copy_len = skb->len + ETH_HLEN;
else
copy_len = uloginfo->cprange;
size = nlmsg_total_size(sizeof(*pm) + copy_len);
if (size > nlbufsiz) {
pr_debug("Size %Zd needed, but nlbufsiz=%d\n", size, nlbufsiz);
return;
}
spin_lock_bh(lock);
if (!ub->skb) {
if (!(ub->skb = ulog_alloc_skb(size)))
goto unlock;
} else if (size > skb_tailroom(ub->skb)) {
ulog_send(ebt, group);
if (!(ub->skb = ulog_alloc_skb(size)))
goto unlock;
}
nlh = nlmsg_put(ub->skb, 0, ub->qlen, 0,
size - NLMSG_ALIGN(sizeof(*nlh)), 0);
if (!nlh) {
kfree_skb(ub->skb);
ub->skb = NULL;
goto unlock;
}
ub->qlen++;
pm = nlmsg_data(nlh);
memset(pm, 0, sizeof(*pm));
/* Fill in the ulog data */
pm->version = EBT_ULOG_VERSION;
kt = ktime_get_real();
pm->stamp = ktime_to_timeval(kt);
if (ub->qlen == 1)
ub->skb->tstamp = kt;
pm->data_len = copy_len;
pm->mark = skb->mark;
pm->hook = hooknr;
if (uloginfo->prefix != NULL)
strcpy(pm->prefix, uloginfo->prefix);
if (in) {
strcpy(pm->physindev, in->name);
/* If in isn't a bridge, then physindev==indev */
if (br_port_exists(in))
/* rcu_read_lock()ed by nf_hook_slow */
strcpy(pm->indev, br_port_get_rcu(in)->br->dev->name);
else
strcpy(pm->indev, in->name);
}
if (out) {
/* If out exists, then out is a bridge port */
strcpy(pm->physoutdev, out->name);
/* rcu_read_lock()ed by nf_hook_slow */
strcpy(pm->outdev, br_port_get_rcu(out)->br->dev->name);
}
if (skb_copy_bits(skb, -ETH_HLEN, pm->data, copy_len) < 0)
BUG();
if (ub->qlen > 1)
ub->lastnlh->nlmsg_flags |= NLM_F_MULTI;
ub->lastnlh = nlh;
if (ub->qlen >= uloginfo->qthreshold)
ulog_send(ebt, group);
else if (!timer_pending(&ub->timer)) {
ub->timer.expires = jiffies + flushtimeout * HZ / 100;
add_timer(&ub->timer);
}
unlock:
spin_unlock_bh(lock);
}
/* this function is registered with the netfilter core */
static void ebt_log_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 *li,
const char *prefix)
{
struct ebt_ulog_info loginfo;
if (!li || li->type != NF_LOG_TYPE_ULOG) {
loginfo.nlgroup = EBT_ULOG_DEFAULT_NLGROUP;
loginfo.cprange = 0;
loginfo.qthreshold = EBT_ULOG_DEFAULT_QTHRESHOLD;
loginfo.prefix[0] = '\0';
} else {
loginfo.nlgroup = li->u.ulog.group;
loginfo.cprange = li->u.ulog.copy_len;
loginfo.qthreshold = li->u.ulog.qthreshold;
strlcpy(loginfo.prefix, prefix, sizeof(loginfo.prefix));
}
ebt_ulog_packet(net, hooknum, skb, in, out, &loginfo, prefix);
}
static unsigned int
ebt_ulog_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
struct net *net = dev_net(par->in ? par->in : par->out);
ebt_ulog_packet(net, par->hooknum, skb, par->in, par->out,
par->targinfo, NULL);
return EBT_CONTINUE;
}
static int ebt_ulog_tg_check(const struct xt_tgchk_param *par)
{
struct ebt_ulog_info *uloginfo = par->targinfo;
if (!par->net->xt.ebt_ulog_warn_deprecated) {
pr_info("ebt_ulog is deprecated and it will be removed soon, "
"use ebt_nflog instead\n");
par->net->xt.ebt_ulog_warn_deprecated = true;
}
if (uloginfo->nlgroup > 31)
return -EINVAL;
uloginfo->prefix[EBT_ULOG_PREFIX_LEN - 1] = '\0';
if (uloginfo->qthreshold > EBT_ULOG_MAX_QLEN)
uloginfo->qthreshold = EBT_ULOG_MAX_QLEN;
return 0;
}
static struct xt_target ebt_ulog_tg_reg __read_mostly = {
.name = "ulog",
.revision = 0,
.family = NFPROTO_BRIDGE,
.target = ebt_ulog_tg,
.checkentry = ebt_ulog_tg_check,
.targetsize = sizeof(struct ebt_ulog_info),
.me = THIS_MODULE,
};
static struct nf_logger ebt_ulog_logger __read_mostly = {
.name = "ebt_ulog",
.logfn = &ebt_log_packet,
.me = THIS_MODULE,
};
static int __net_init ebt_ulog_net_init(struct net *net)
{
int i;
struct ebt_ulog_net *ebt = ebt_ulog_pernet(net);
struct netlink_kernel_cfg cfg = {
.groups = EBT_ULOG_MAXNLGROUPS,
};
/* initialize ulog_buffers */
for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
ebt->nlgroup[i] = i;
setup_timer(&ebt->ulog_buffers[i].timer, ulog_timer,
(unsigned long)&ebt->nlgroup[i]);
spin_lock_init(&ebt->ulog_buffers[i].lock);
}
ebt->ebtulognl = netlink_kernel_create(net, NETLINK_NFLOG, &cfg);
if (!ebt->ebtulognl)
return -ENOMEM;
nf_log_set(net, NFPROTO_BRIDGE, &ebt_ulog_logger);
return 0;
}
static void __net_exit ebt_ulog_net_fini(struct net *net)
{
int i;
struct ebt_ulog_net *ebt = ebt_ulog_pernet(net);
nf_log_unset(net, &ebt_ulog_logger);
for (i = 0; i < EBT_ULOG_MAXNLGROUPS; i++) {
ebt_ulog_buff_t *ub = &ebt->ulog_buffers[i];
del_timer(&ub->timer);
if (ub->skb) {
kfree_skb(ub->skb);
ub->skb = NULL;
}
}
netlink_kernel_release(ebt->ebtulognl);
}
static struct pernet_operations ebt_ulog_net_ops = {
.init = ebt_ulog_net_init,
.exit = ebt_ulog_net_fini,
.id = &ebt_ulog_net_id,
.size = sizeof(struct ebt_ulog_net),
};
static int __init ebt_ulog_init(void)
{
int ret;
if (nlbufsiz >= 128*1024) {
pr_warn("Netlink buffer has to be <= 128kB,"
"please try a smaller nlbufsiz parameter.\n");
return -EINVAL;
}
ret = register_pernet_subsys(&ebt_ulog_net_ops);
if (ret)
goto out_pernet;
ret = xt_register_target(&ebt_ulog_tg_reg);
if (ret)
goto out_target;
nf_log_register(NFPROTO_BRIDGE, &ebt_ulog_logger);
return 0;
out_target:
unregister_pernet_subsys(&ebt_ulog_net_ops);
out_pernet:
return ret;
}
static void __exit ebt_ulog_fini(void)
{
nf_log_unregister(&ebt_ulog_logger);
xt_unregister_target(&ebt_ulog_tg_reg);
unregister_pernet_subsys(&ebt_ulog_net_ops);
}
module_init(ebt_ulog_init);
module_exit(ebt_ulog_fini);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Bart De Schuymer <bdschuym@pandora.be>");
MODULE_DESCRIPTION("Ebtables: Packet logging to netlink using ULOG");
......@@ -159,25 +159,6 @@ config IP_NF_TARGET_SYNPROXY
To compile it as a module, choose M here. If unsure, say N.
config IP_NF_TARGET_ULOG
tristate "ULOG target support (obsolete)"
default m if NETFILTER_ADVANCED=n
---help---
This option enables the old IPv4-only "ipt_ULOG" implementation
which has been obsoleted by the new "nfnetlink_log" code (see
CONFIG_NETFILTER_NETLINK_LOG).
This option adds a `ULOG' target, which allows you to create rules in
any iptables table. The packet is passed to a userspace logging
daemon using netlink multicast sockets; unlike the LOG target
which can only be viewed through syslog.
The appropriate userspace logging daemon (ulogd) may be obtained from
<http://www.netfilter.org/projects/ulogd/index.html>
To compile it as a module, choose M here. If unsure, say N.
# NAT + specific targets: nf_conntrack
config NF_NAT_IPV4
tristate "IPv4 NAT"
......
/*
* netfilter module for userspace packet logging daemons
*
* (C) 2000-2004 by Harald Welte <laforge@netfilter.org>
* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
* (C) 2005-2007 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This module accepts two parameters:
*
* nlbufsiz:
* The parameter specifies how big the buffer for each netlink multicast
* group is. e.g. If you say nlbufsiz=8192, up to eight kb of packets will
* get accumulated in the kernel until they are sent to userspace. It is
* NOT possible to allocate more than 128kB, and it is strongly discouraged,
* because atomically allocating 128kB inside the network rx softirq is not
* reliable. Please also keep in mind that this buffer size is allocated for
* each nlgroup you are using, so the total kernel memory usage increases
* by that factor.
*
* Actually you should use nlbufsiz a bit smaller than PAGE_SIZE, since
* nlbufsiz is used with alloc_skb, which adds another
* sizeof(struct skb_shared_info). Use NLMSG_GOODSIZE instead.
*
* flushtimeout:
* Specify, after how many hundredths of a second the queue should be
* flushed even if it is not full yet.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/socket.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <net/netlink.h>
#include <linux/netdevice.h>
#include <linux/mm.h>
#include <linux/moduleparam.h>
#include <linux/netfilter.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ipt_ULOG.h>
#include <net/netfilter/nf_log.h>
#include <net/netns/generic.h>
#include <net/sock.h>
#include <linux/bitops.h>
#include <asm/unaligned.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
MODULE_DESCRIPTION("Xtables: packet logging to netlink using ULOG");
MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NFLOG);
#define ULOG_NL_EVENT 111 /* Harald's favorite number */
#define ULOG_MAXNLGROUPS 32 /* numer of nlgroups */
static unsigned int nlbufsiz = NLMSG_GOODSIZE;
module_param(nlbufsiz, uint, 0400);
MODULE_PARM_DESC(nlbufsiz, "netlink buffer size");
static unsigned int flushtimeout = 10;
module_param(flushtimeout, uint, 0600);
MODULE_PARM_DESC(flushtimeout, "buffer flush timeout (hundredths of a second)");
static bool nflog = true;
module_param(nflog, bool, 0400);
MODULE_PARM_DESC(nflog, "register as internal netfilter logging module");
/* global data structures */
typedef struct {
unsigned int qlen; /* number of nlmsgs' in the skb */
struct nlmsghdr *lastnlh; /* netlink header of last msg in skb */
struct sk_buff *skb; /* the pre-allocated skb */
struct timer_list timer; /* the timer function */
} ulog_buff_t;
static int ulog_net_id __read_mostly;
struct ulog_net {
unsigned int nlgroup[ULOG_MAXNLGROUPS];
ulog_buff_t ulog_buffers[ULOG_MAXNLGROUPS];
struct sock *nflognl;
spinlock_t lock;
};
static struct ulog_net *ulog_pernet(struct net *net)
{
return net_generic(net, ulog_net_id);
}
/* send one ulog_buff_t to userspace */
static void ulog_send(struct ulog_net *ulog, unsigned int nlgroupnum)
{
ulog_buff_t *ub = &ulog->ulog_buffers[nlgroupnum];
pr_debug("ulog_send: timer is deleting\n");
del_timer(&ub->timer);
if (!ub->skb) {
pr_debug("ulog_send: nothing to send\n");
return;
}
/* last nlmsg needs NLMSG_DONE */
if (ub->qlen > 1)
ub->lastnlh->nlmsg_type = NLMSG_DONE;
NETLINK_CB(ub->skb).dst_group = nlgroupnum + 1;
pr_debug("throwing %d packets to netlink group %u\n",
ub->qlen, nlgroupnum + 1);
netlink_broadcast(ulog->nflognl, ub->skb, 0, nlgroupnum + 1,
GFP_ATOMIC);
ub->qlen = 0;
ub->skb = NULL;
ub->lastnlh = NULL;
}
/* timer function to flush queue in flushtimeout time */
static void ulog_timer(unsigned long data)
{
unsigned int groupnum = *((unsigned int *)data);
struct ulog_net *ulog = container_of((void *)data,
struct ulog_net,
nlgroup[groupnum]);
pr_debug("timer function called, calling ulog_send\n");
/* lock to protect against somebody modifying our structure
* from ipt_ulog_target at the same time */
spin_lock_bh(&ulog->lock);
ulog_send(ulog, groupnum);
spin_unlock_bh(&ulog->lock);
}
static struct sk_buff *ulog_alloc_skb(unsigned int size)
{
struct sk_buff *skb;
unsigned int n;
/* alloc skb which should be big enough for a whole
* multipart message. WARNING: has to be <= 131000
* due to slab allocator restrictions */
n = max(size, nlbufsiz);
skb = alloc_skb(n, GFP_ATOMIC | __GFP_NOWARN);
if (!skb) {
if (n > size) {
/* try to allocate only as much as we need for
* current packet */
skb = alloc_skb(size, GFP_ATOMIC);
if (!skb)
pr_debug("cannot even allocate %ub\n", size);
}
}
return skb;
}
static void ipt_ulog_packet(struct net *net,
unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const struct ipt_ulog_info *loginfo,
const char *prefix)
{
ulog_buff_t *ub;
ulog_packet_msg_t *pm;
size_t size, copy_len;
struct nlmsghdr *nlh;
struct timeval tv;
struct ulog_net *ulog = ulog_pernet(net);
/* ffs == find first bit set, necessary because userspace
* is already shifting groupnumber, but we need unshifted.
* ffs() returns [1..32], we need [0..31] */
unsigned int groupnum = ffs(loginfo->nl_group) - 1;
/* calculate the size of the skb needed */
if (loginfo->copy_range == 0 || loginfo->copy_range > skb->len)
copy_len = skb->len;
else
copy_len = loginfo->copy_range;
size = nlmsg_total_size(sizeof(*pm) + copy_len);
ub = &ulog->ulog_buffers[groupnum];
spin_lock_bh(&ulog->lock);
if (!ub->skb) {
if (!(ub->skb = ulog_alloc_skb(size)))
goto alloc_failure;
} else if (ub->qlen >= loginfo->qthreshold ||
size > skb_tailroom(ub->skb)) {
/* either the queue len is too high or we don't have
* enough room in nlskb left. send it to userspace. */
ulog_send(ulog, groupnum);
if (!(ub->skb = ulog_alloc_skb(size)))
goto alloc_failure;
}
pr_debug("qlen %d, qthreshold %Zu\n", ub->qlen, loginfo->qthreshold);
nlh = nlmsg_put(ub->skb, 0, ub->qlen, ULOG_NL_EVENT,
sizeof(*pm)+copy_len, 0);
if (!nlh) {
pr_debug("error during nlmsg_put\n");
goto out_unlock;
}
ub->qlen++;
pm = nlmsg_data(nlh);
memset(pm, 0, sizeof(*pm));
/* We might not have a timestamp, get one */
if (skb->tstamp.tv64 == 0)
__net_timestamp((struct sk_buff *)skb);
/* copy hook, prefix, timestamp, payload, etc. */
pm->data_len = copy_len;
tv = ktime_to_timeval(skb->tstamp);
put_unaligned(tv.tv_sec, &pm->timestamp_sec);
put_unaligned(tv.tv_usec, &pm->timestamp_usec);
put_unaligned(skb->mark, &pm->mark);
pm->hook = hooknum;
if (prefix != NULL) {
strncpy(pm->prefix, prefix, sizeof(pm->prefix) - 1);
pm->prefix[sizeof(pm->prefix) - 1] = '\0';
}
else if (loginfo->prefix[0] != '\0')
strncpy(pm->prefix, loginfo->prefix, sizeof(pm->prefix));
if (in && in->hard_header_len > 0 &&
skb->mac_header != skb->network_header &&
in->hard_header_len <= ULOG_MAC_LEN) {
memcpy(pm->mac, skb_mac_header(skb), in->hard_header_len);
pm->mac_len = in->hard_header_len;
} else
pm->mac_len = 0;
if (in)
strncpy(pm->indev_name, in->name, sizeof(pm->indev_name));
if (out)
strncpy(pm->outdev_name, out->name, sizeof(pm->outdev_name));
/* copy_len <= skb->len, so can't fail. */
if (skb_copy_bits(skb, 0, pm->payload, copy_len) < 0)
BUG();
/* check if we are building multi-part messages */
if (ub->qlen > 1)
ub->lastnlh->nlmsg_flags |= NLM_F_MULTI;
ub->lastnlh = nlh;
/* if timer isn't already running, start it */
if (!timer_pending(&ub->timer)) {
ub->timer.expires = jiffies + flushtimeout * HZ / 100;
add_timer(&ub->timer);
}
/* if threshold is reached, send message to userspace */
if (ub->qlen >= loginfo->qthreshold) {
if (loginfo->qthreshold > 1)
nlh->nlmsg_type = NLMSG_DONE;
ulog_send(ulog, groupnum);
}
out_unlock:
spin_unlock_bh(&ulog->lock);
return;
alloc_failure:
pr_debug("Error building netlink message\n");
spin_unlock_bh(&ulog->lock);
}
static unsigned int
ulog_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
struct net *net = dev_net(par->in ? par->in : par->out);
ipt_ulog_packet(net, par->hooknum, skb, par->in, par->out,
par->targinfo, NULL);
return XT_CONTINUE;
}
static void ipt_logfn(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 *li,
const char *prefix)
{
struct ipt_ulog_info loginfo;
if (!li || li->type != NF_LOG_TYPE_ULOG) {
loginfo.nl_group = ULOG_DEFAULT_NLGROUP;
loginfo.copy_range = 0;
loginfo.qthreshold = ULOG_DEFAULT_QTHRESHOLD;
loginfo.prefix[0] = '\0';
} else {
loginfo.nl_group = li->u.ulog.group;
loginfo.copy_range = li->u.ulog.copy_len;
loginfo.qthreshold = li->u.ulog.qthreshold;
strlcpy(loginfo.prefix, prefix, sizeof(loginfo.prefix));
}
ipt_ulog_packet(net, hooknum, skb, in, out, &loginfo, prefix);
}
static int ulog_tg_check(const struct xt_tgchk_param *par)
{
const struct ipt_ulog_info *loginfo = par->targinfo;
if (!par->net->xt.ulog_warn_deprecated) {
pr_info("ULOG is deprecated and it will be removed soon, "
"use NFLOG instead\n");
par->net->xt.ulog_warn_deprecated = true;
}
if (loginfo->prefix[sizeof(loginfo->prefix) - 1] != '\0') {
pr_debug("prefix not null-terminated\n");
return -EINVAL;
}
if (loginfo->qthreshold > ULOG_MAX_QLEN) {
pr_debug("queue threshold %Zu > MAX_QLEN\n",
loginfo->qthreshold);
return -EINVAL;
}
return 0;
}
#ifdef CONFIG_COMPAT
struct compat_ipt_ulog_info {
compat_uint_t nl_group;
compat_size_t copy_range;
compat_size_t qthreshold;
char prefix[ULOG_PREFIX_LEN];
};
static void ulog_tg_compat_from_user(void *dst, const void *src)
{
const struct compat_ipt_ulog_info *cl = src;
struct ipt_ulog_info l = {
.nl_group = cl->nl_group,
.copy_range = cl->copy_range,
.qthreshold = cl->qthreshold,
};
memcpy(l.prefix, cl->prefix, sizeof(l.prefix));
memcpy(dst, &l, sizeof(l));
}
static int ulog_tg_compat_to_user(void __user *dst, const void *src)
{
const struct ipt_ulog_info *l = src;
struct compat_ipt_ulog_info cl = {
.nl_group = l->nl_group,
.copy_range = l->copy_range,
.qthreshold = l->qthreshold,
};
memcpy(cl.prefix, l->prefix, sizeof(cl.prefix));
return copy_to_user(dst, &cl, sizeof(cl)) ? -EFAULT : 0;
}
#endif /* CONFIG_COMPAT */
static struct xt_target ulog_tg_reg __read_mostly = {
.name = "ULOG",
.family = NFPROTO_IPV4,
.target = ulog_tg,
.targetsize = sizeof(struct ipt_ulog_info),
.checkentry = ulog_tg_check,
#ifdef CONFIG_COMPAT
.compatsize = sizeof(struct compat_ipt_ulog_info),
.compat_from_user = ulog_tg_compat_from_user,
.compat_to_user = ulog_tg_compat_to_user,
#endif
.me = THIS_MODULE,
};
static struct nf_logger ipt_ulog_logger __read_mostly = {
.name = "ipt_ULOG",
.logfn = ipt_logfn,
.me = THIS_MODULE,
};
static int __net_init ulog_tg_net_init(struct net *net)
{
int i;
struct ulog_net *ulog = ulog_pernet(net);
struct netlink_kernel_cfg cfg = {
.groups = ULOG_MAXNLGROUPS,
};
spin_lock_init(&ulog->lock);
/* initialize ulog_buffers */
for (i = 0; i < ULOG_MAXNLGROUPS; i++) {
ulog->nlgroup[i] = i;
setup_timer(&ulog->ulog_buffers[i].timer, ulog_timer,
(unsigned long)&ulog->nlgroup[i]);
}
ulog->nflognl = netlink_kernel_create(net, NETLINK_NFLOG, &cfg);
if (!ulog->nflognl)
return -ENOMEM;
if (nflog)
nf_log_set(net, NFPROTO_IPV4, &ipt_ulog_logger);
return 0;
}
static void __net_exit ulog_tg_net_exit(struct net *net)
{
ulog_buff_t *ub;
int i;
struct ulog_net *ulog = ulog_pernet(net);
if (nflog)
nf_log_unset(net, &ipt_ulog_logger);
netlink_kernel_release(ulog->nflognl);
/* remove pending timers and free allocated skb's */
for (i = 0; i < ULOG_MAXNLGROUPS; i++) {
ub = &ulog->ulog_buffers[i];
pr_debug("timer is deleting\n");
del_timer(&ub->timer);
if (ub->skb) {
kfree_skb(ub->skb);
ub->skb = NULL;
}
}
}
static struct pernet_operations ulog_tg_net_ops = {
.init = ulog_tg_net_init,
.exit = ulog_tg_net_exit,
.id = &ulog_net_id,
.size = sizeof(struct ulog_net),
};
static int __init ulog_tg_init(void)
{
int ret;
pr_debug("init module\n");
if (nlbufsiz > 128*1024) {
pr_warn("Netlink buffer has to be <= 128kB\n");
return -EINVAL;
}
ret = register_pernet_subsys(&ulog_tg_net_ops);
if (ret)
goto out_pernet;
ret = xt_register_target(&ulog_tg_reg);
if (ret < 0)
goto out_target;
if (nflog)
nf_log_register(NFPROTO_IPV4, &ipt_ulog_logger);
return 0;
out_target:
unregister_pernet_subsys(&ulog_tg_net_ops);
out_pernet:
return ret;
}
static void __exit ulog_tg_exit(void)
{
pr_debug("cleanup_module\n");
if (nflog)
nf_log_unregister(&ipt_ulog_logger);
xt_unregister_target(&ulog_tg_reg);
unregister_pernet_subsys(&ulog_tg_net_ops);
}
module_init(ulog_tg_init);
module_exit(ulog_tg_exit);
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