Commit f6ebe77f authored by Harald Welte's avatar Harald Welte Committed by David S. Miller
Browse files

[NETFILTER]: split net/core/netfilter.c into net/netfilter/*.c



This patch doesn't introduce any code changes, but merely splits the
core netfilter code into four separate files.  It also moves it from
it's old location in net/core/ to the recently-created net/netfilter/
directory.
Signed-off-by: default avatarHarald Welte <laforge@netfilter.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 210a9ebe
......@@ -12,7 +12,6 @@ obj-y += dev.o ethtool.o dev_mcast.o dst.o \
obj-$(CONFIG_XFRM) += flow.o
obj-$(CONFIG_SYSFS) += net-sysfs.o
obj-$(CONFIG_NETFILTER) += netfilter.o
obj-$(CONFIG_NET_DIVERT) += dv.o
obj-$(CONFIG_NET_PKTGEN) += pktgen.o
obj-$(CONFIG_NET_RADIO) += wireless.o
......
netfilter-objs := core.o nf_log.o nf_queue.o nf_sockopt.o
obj-$(CONFIG_NETFILTER) = netfilter.o
obj-$(CONFIG_NETFILTER_NETLINK) += nfnetlink.o
obj-$(CONFIG_NETFILTER_NETLINK_QUEUE) += nfnetlink_queue.o
obj-$(CONFIG_NETFILTER_NETLINK_LOG) += nfnetlink_log.o
/* netfilter.c: look after the filters for various protocols.
* Heavily influenced by the old firewall.c by David Bonn and Alan Cox.
*
* Thanks to Rob `CmdrTaco' Malda for not influencing this code in any
* way.
*
* Rusty Russell (C)2000 -- This code is GPL.
*
* February 2000: Modified by James Morris to have 1 queue per protocol.
* 15-Mar-2000: Added NF_REPEAT --RR.
* 08-May-2003: Internal logging interface added by Jozsef Kadlecsik.
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/netfilter.h>
#include <net/protocol.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/wait.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/if.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/proc_fs.h>
#include <net/sock.h>
#include "nf_internals.h"
/* In this code, we can be waiting indefinitely for userspace to
* service a packet if a hook returns NF_QUEUE. We could keep a count
* of skbuffs queued for userspace, and not deregister a hook unless
* this is zero, but that sucks. Now, we simply check when the
* packets come back: if the hook is gone, the packet is discarded. */
struct list_head nf_hooks[NPROTO][NF_MAX_HOOKS];
EXPORT_SYMBOL(nf_hooks);
static DEFINE_SPINLOCK(nf_hook_lock);
int nf_register_hook(struct nf_hook_ops *reg)
{
struct list_head *i;
spin_lock_bh(&nf_hook_lock);
list_for_each(i, &nf_hooks[reg->pf][reg->hooknum]) {
if (reg->priority < ((struct nf_hook_ops *)i)->priority)
break;
}
list_add_rcu(&reg->list, i->prev);
spin_unlock_bh(&nf_hook_lock);
synchronize_net();
return 0;
}
EXPORT_SYMBOL(nf_register_hook);
void nf_unregister_hook(struct nf_hook_ops *reg)
{
spin_lock_bh(&nf_hook_lock);
list_del_rcu(&reg->list);
spin_unlock_bh(&nf_hook_lock);
synchronize_net();
}
EXPORT_SYMBOL(nf_unregister_hook);
unsigned int nf_iterate(struct list_head *head,
struct sk_buff **skb,
int hook,
const struct net_device *indev,
const struct net_device *outdev,
struct list_head **i,
int (*okfn)(struct sk_buff *),
int hook_thresh)
{
unsigned int verdict;
/*
* The caller must not block between calls to this
* function because of risk of continuing from deleted element.
*/
list_for_each_continue_rcu(*i, head) {
struct nf_hook_ops *elem = (struct nf_hook_ops *)*i;
if (hook_thresh > elem->priority)
continue;
/* Optimization: we don't need to hold module
reference here, since function can't sleep. --RR */
verdict = elem->hook(hook, skb, indev, outdev, okfn);
if (verdict != NF_ACCEPT) {
#ifdef CONFIG_NETFILTER_DEBUG
if (unlikely((verdict & NF_VERDICT_MASK)
> NF_MAX_VERDICT)) {
NFDEBUG("Evil return from %p(%u).\n",
elem->hook, hook);
continue;
}
#endif
if (verdict != NF_REPEAT)
return verdict;
*i = (*i)->prev;
}
}
return NF_ACCEPT;
}
/* Returns 1 if okfn() needs to be executed by the caller,
* -EPERM for NF_DROP, 0 otherwise. */
int nf_hook_slow(int pf, unsigned int hook, struct sk_buff **pskb,
struct net_device *indev,
struct net_device *outdev,
int (*okfn)(struct sk_buff *),
int hook_thresh)
{
struct list_head *elem;
unsigned int verdict;
int ret = 0;
/* We may already have this, but read-locks nest anyway */
rcu_read_lock();
elem = &nf_hooks[pf][hook];
next_hook:
verdict = nf_iterate(&nf_hooks[pf][hook], pskb, hook, indev,
outdev, &elem, okfn, hook_thresh);
if (verdict == NF_ACCEPT || verdict == NF_STOP) {
ret = 1;
goto unlock;
} else if (verdict == NF_DROP) {
kfree_skb(*pskb);
ret = -EPERM;
} else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE) {
NFDEBUG("nf_hook: Verdict = QUEUE.\n");
if (!nf_queue(pskb, elem, pf, hook, indev, outdev, okfn,
verdict >> NF_VERDICT_BITS))
goto next_hook;
}
unlock:
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL(nf_hook_slow);
int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len)
{
struct sk_buff *nskb;
if (writable_len > (*pskb)->len)
return 0;
/* Not exclusive use of packet? Must copy. */
if (skb_shared(*pskb) || skb_cloned(*pskb))
goto copy_skb;
return pskb_may_pull(*pskb, writable_len);
copy_skb:
nskb = skb_copy(*pskb, GFP_ATOMIC);
if (!nskb)
return 0;
BUG_ON(skb_is_nonlinear(nskb));
/* Rest of kernel will get very unhappy if we pass it a
suddenly-orphaned skbuff */
if ((*pskb)->sk)
skb_set_owner_w(nskb, (*pskb)->sk);
kfree_skb(*pskb);
*pskb = nskb;
return 1;
}
EXPORT_SYMBOL(skb_make_writable);
/* This does not belong here, but locally generated errors need it if connection
tracking in use: without this, connection may not be in hash table, and hence
manufactured ICMP or RST packets will not be associated with it. */
void (*ip_ct_attach)(struct sk_buff *, struct sk_buff *);
EXPORT_SYMBOL(ip_ct_attach);
void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb)
{
void (*attach)(struct sk_buff *, struct sk_buff *);
if (skb->nfct && (attach = ip_ct_attach) != NULL) {
mb(); /* Just to be sure: must be read before executing this */
attach(new, skb);
}
}
EXPORT_SYMBOL(nf_ct_attach);
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *proc_net_netfilter;
EXPORT_SYMBOL(proc_net_netfilter);
#endif
void __init netfilter_init(void)
{
int i, h;
for (i = 0; i < NPROTO; i++) {
for (h = 0; h < NF_MAX_HOOKS; h++)
INIT_LIST_HEAD(&nf_hooks[i][h]);
}
#ifdef CONFIG_PROC_FS
proc_net_netfilter = proc_mkdir("netfilter", proc_net);
if (!proc_net_netfilter)
panic("cannot create netfilter proc entry");
#endif
if (netfilter_queue_init() < 0)
panic("cannot initialize nf_queue");
if (netfilter_log_init() < 0)
panic("cannot initialize nf_log");
}
#ifndef _NF_INTERNALS_H
#define _NF_INTERNALS_H
#include <linux/config.h>
#include <linux/list.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#ifdef CONFIG_NETFILTER_DEBUG
#define NFDEBUG(format, args...) printk(format , ## args)
#else
#define NFDEBUG(format, args...)
#endif
/* core.c */
extern unsigned int nf_iterate(struct list_head *head,
struct sk_buff **skb,
int hook,
const struct net_device *indev,
const struct net_device *outdev,
struct list_head **i,
int (*okfn)(struct sk_buff *),
int hook_thresh);
/* nf_queue.c */
extern int nf_queue(struct sk_buff **skb,
struct list_head *elem,
int pf, unsigned int hook,
struct net_device *indev,
struct net_device *outdev,
int (*okfn)(struct sk_buff *),
unsigned int queuenum);
extern int __init netfilter_queue_init(void);
/* nf_log.c */
extern int __init netfilter_log_init(void);
#endif
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/skbuff.h>
#include <linux/netfilter.h>
#include <net/protocol.h>
#include "nf_internals.h"
/* Internal logging interface, which relies on the real
LOG target modules */
#define NF_LOG_PREFIXLEN 128
static struct nf_logger *nf_logging[NPROTO]; /* = NULL */
static DEFINE_SPINLOCK(nf_log_lock);
int nf_log_register(int pf, struct nf_logger *logger)
{
int ret = -EBUSY;
/* Any setup of logging members must be done before
* substituting pointer. */
spin_lock(&nf_log_lock);
if (!nf_logging[pf]) {
rcu_assign_pointer(nf_logging[pf], logger);
ret = 0;
}
spin_unlock(&nf_log_lock);
return ret;
}
EXPORT_SYMBOL(nf_log_register);
void nf_log_unregister_pf(int pf)
{
spin_lock(&nf_log_lock);
nf_logging[pf] = NULL;
spin_unlock(&nf_log_lock);
/* Give time to concurrent readers. */
synchronize_net();
}
EXPORT_SYMBOL(nf_log_unregister_pf);
void nf_log_unregister_logger(struct nf_logger *logger)
{
int i;
spin_lock(&nf_log_lock);
for (i = 0; i < NPROTO; i++) {
if (nf_logging[i] == logger)
nf_logging[i] = NULL;
}
spin_unlock(&nf_log_lock);
synchronize_net();
}
EXPORT_SYMBOL(nf_log_unregister_logger);
void nf_log_packet(int pf,
unsigned int hooknum,
const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
struct nf_loginfo *loginfo,
const char *fmt, ...)
{
va_list args;
char prefix[NF_LOG_PREFIXLEN];
struct nf_logger *logger;
rcu_read_lock();
logger = rcu_dereference(nf_logging[pf]);
if (logger) {
va_start(args, fmt);
vsnprintf(prefix, sizeof(prefix), fmt, args);
va_end(args);
/* We must read logging before nf_logfn[pf] */
logger->logfn(pf, hooknum, skb, in, out, loginfo, prefix);
} else if (net_ratelimit()) {
printk(KERN_WARNING "nf_log_packet: can\'t log since "
"no backend logging module loaded in! Please either "
"load one, or disable logging explicitly\n");
}
rcu_read_unlock();
}
EXPORT_SYMBOL(nf_log_packet);
#ifdef CONFIG_PROC_FS
static void *seq_start(struct seq_file *seq, loff_t *pos)
{
rcu_read_lock();
if (*pos >= NPROTO)
return NULL;
return pos;
}
static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
{
(*pos)++;
if (*pos >= NPROTO)
return NULL;
return pos;
}
static void seq_stop(struct seq_file *s, void *v)
{
rcu_read_unlock();
}
static int seq_show(struct seq_file *s, void *v)
{
loff_t *pos = v;
const struct nf_logger *logger;
logger = rcu_dereference(nf_logging[*pos]);
if (!logger)
return seq_printf(s, "%2lld NONE\n", *pos);
return seq_printf(s, "%2lld %s\n", *pos, logger->name);
}
static struct seq_operations nflog_seq_ops = {
.start = seq_start,
.next = seq_next,
.stop = seq_stop,
.show = seq_show,
};
static int nflog_open(struct inode *inode, struct file *file)
{
return seq_open(file, &nflog_seq_ops);
}
static struct file_operations nflog_file_ops = {
.owner = THIS_MODULE,
.open = nflog_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
#endif /* PROC_FS */
int __init netfilter_log_init(void)
{
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *pde;
pde = create_proc_entry("nf_log", S_IRUGO, proc_net_netfilter);
#endif
if (!pde)
return -1;
pde->proc_fops = &nflog_file_ops;
return 0;
}
/* netfilter.c: look after the filters for various protocols.
* Heavily influenced by the old firewall.c by David Bonn and Alan Cox.
*
* Thanks to Rob `CmdrTaco' Malda for not influencing this code in any
* way.
*
* Rusty Russell (C)2000 -- This code is GPL.
*
* February 2000: Modified by James Morris to have 1 queue per protocol.
* 15-Mar-2000: Added NF_REPEAT --RR.
* 08-May-2003: Internal logging interface added by Jozsef Kadlecsik.
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/netfilter.h>
#include <net/protocol.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/wait.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/if.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/proc_fs.h>
#include <net/sock.h>
/* In this code, we can be waiting indefinitely for userspace to
* service a packet if a hook returns NF_QUEUE. We could keep a count
* of skbuffs queued for userspace, and not deregister a hook unless
* this is zero, but that sucks. Now, we simply check when the
* packets come back: if the hook is gone, the packet is discarded. */
#ifdef CONFIG_NETFILTER_DEBUG
#define NFDEBUG(format, args...) printk(format , ## args)
#else
#define NFDEBUG(format, args...)
#endif
/* Sockopts only registered and called from user context, so
net locking would be overkill. Also, [gs]etsockopt calls may
sleep. */
static DECLARE_MUTEX(nf_sockopt_mutex);
#include <linux/skbuff.h>
#include <linux/netfilter.h>
#include <net/protocol.h>
struct list_head nf_hooks[NPROTO][NF_MAX_HOOKS];
static LIST_HEAD(nf_sockopts);
static DEFINE_SPINLOCK(nf_hook_lock);
#include "nf_internals.h"
/*
* A queue handler may be registered for each protocol. Each is protected by
......@@ -59,183 +23,6 @@ static struct nf_queue_rerouter *queue_rerouter;
static DEFINE_RWLOCK(queue_handler_lock);
int nf_register_hook(struct nf_hook_ops *reg)
{
struct list_head *i;
spin_lock_bh(&nf_hook_lock);
list_for_each(i, &nf_hooks[reg->pf][reg->hooknum]) {
if (reg->priority < ((struct nf_hook_ops *)i)->priority)
break;
}
list_add_rcu(&reg->list, i->prev);
spin_unlock_bh(&nf_hook_lock);
synchronize_net();
return 0;
}
void nf_unregister_hook(struct nf_hook_ops *reg)
{
spin_lock_bh(&nf_hook_lock);
list_del_rcu(&reg->list);
spin_unlock_bh(&nf_hook_lock);
synchronize_net();
}
/* Do exclusive ranges overlap? */
static inline int overlap(int min1, int max1, int min2, int max2)
{
return max1 > min2 && min1 < max2;
}
/* Functions to register sockopt ranges (exclusive). */
int nf_register_sockopt(struct nf_sockopt_ops *reg)
{
struct list_head *i;
int ret = 0;
if (down_interruptible(&nf_sockopt_mutex) != 0)
return -EINTR;
list_for_each(i, &nf_sockopts) {
struct nf_sockopt_ops *ops = (struct nf_sockopt_ops *)i;
if (ops->pf == reg->pf
&& (overlap(ops->set_optmin, ops->set_optmax,
reg->set_optmin, reg->set_optmax)
|| overlap(ops->get_optmin, ops->get_optmax,
reg->get_optmin, reg->get_optmax))) {
NFDEBUG("nf_sock overlap: %u-%u/%u-%u v %u-%u/%u-%u\n",
ops->set_optmin, ops->set_optmax,
ops->get_optmin, ops->get_optmax,
reg->set_optmin, reg->set_optmax,
reg->get_optmin, reg->get_optmax);
ret = -EBUSY;
goto out;
}
}
list_add(&reg->list, &nf_sockopts);
out:
up(&nf_sockopt_mutex);
return ret;
}
void nf_unregister_sockopt(struct nf_sockopt_ops *reg)
{
/* No point being interruptible: we're probably in cleanup_module() */
restart:
down(&nf_sockopt_mutex);
if (reg->use != 0) {
/* To be woken by nf_sockopt call... */
/* FIXME: Stuart Young's name appears gratuitously. */
set_current_state(TASK_UNINTERRUPTIBLE);
reg->cleanup_task = current;
up(&nf_sockopt_mutex);
schedule();
goto restart;
}
list_del(&reg->list);
up(&nf_sockopt_mutex);
}
/* Call get/setsockopt() */
static int nf_sockopt(struct sock *sk, int pf, int val,
char __user *opt, int *len, int get)
{
struct list_head *i;
struct nf_sockopt_ops *ops;
int ret;
if (down_interruptible(&nf_sockopt_mutex) != 0)
return -EINTR;
list_for_each(i, &nf_sockopts) {
ops = (struct nf_sockopt_ops *)i;
if (ops->pf == pf) {
if (get) {
if (val >= ops->get_optmin
&& val < ops->get_optmax) {
ops->use++;
up(&nf_sockopt_mutex);
ret = ops->get(sk, val, opt, len);
goto out;
}
} else {
if (val >= ops->set_optmin
&& val < ops->set_optmax) {
ops->use++;
up(&nf_sockopt_mutex);
ret = ops->set(sk, val, opt, *len);
goto out;
}
}
}
}
up(&nf_sockopt_mutex);
return -ENOPROTOOPT;
out:
down(&nf_sockopt_mutex);
ops->use--;
if (ops->cleanup_task)
wake_up_process(ops->cleanup_task);
up(&nf_sockopt_mutex);
return ret;
}
int nf_setsockopt(struct sock *sk, int pf, int val, char __user *opt,
int len)