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Commit ff5d22a4 authored by David S. Miller's avatar David S. Miller
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Netfilter updates from Harald Welte and myself: 

1) implement missing ip_conntrack_protocol_unregister function
2) export ip_conntrack_unexpect_related symbol
3) add support for destination nat on locally initiated connections
4) add hooks for the filtering of ARP packets
parent abb85ec3
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Showing with 1980 additions and 38 deletions
include/linux/netfilter_arp.h 0 → 100644
View file @ ff5d22a4
#ifndef __LINUX_ARP_NETFILTER_H
#define __LINUX_ARP_NETFILTER_H
/* ARP-specific defines for netfilter.
* (C)2002 Rusty Russell IBM -- This code is GPL.
*/
#include <linux/config.h>
#include <linux/netfilter.h>
/* There is no PF_ARP. */
#define NF_ARP 0
/* ARP Hooks */
#define NF_ARP_IN 0
#define NF_ARP_OUT 1
#define NF_ARP_NUMHOOKS 2
#endif /* __LINUX_ARP_NETFILTER_H */
include/linux/netfilter_arp/arp_tables.h 0 → 100644
View file @ ff5d22a4
/*
* Format of an ARP firewall descriptor
*
* src, tgt, src_mask, tgt_mask, arpop, arpop_mask are always stored in
* network byte order.
* flags are stored in host byte order (of course).
*/
#ifndef _ARPTABLES_H
#define _ARPTABLES_H
#ifdef __KERNEL__
#include <linux/if.h>
#include <linux/types.h>
#include <linux/in.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#endif
#include <linux/netfilter_arp.h>
#define ARPT_FUNCTION_MAXNAMELEN 30
#define ARPT_TABLE_MAXNAMELEN 32
#define ARPT_DEV_ADDR_LEN_MAX 16
struct arpt_devaddr_info {
char addr[ARPT_DEV_ADDR_LEN_MAX];
char mask[ARPT_DEV_ADDR_LEN_MAX];
};
/* Yes, Virginia, you have to zero the padding. */
struct arpt_arp {
/* Source and target IP addr */
struct in_addr src, tgt;
/* Mask for src and target IP addr */
struct in_addr smsk, tmsk;
/* Device hw address length, src+target device addresses */
u_int8_t arhln, arhln_mask;
struct arpt_devaddr_info src_devaddr;
struct arpt_devaddr_info tgt_devaddr;
/* ARP operation code. */
u_int16_t arpop, arpop_mask;
/* ARP hardware address and protocol address format. */
u_int16_t arhrd, arhrd_mask;
u_int16_t arpro, arpro_mask;
/* The protocol address length is only accepted if it is 4
* so there is no use in offering a way to do filtering on it.
*/
char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];
/* Flags word */
u_int8_t flags;
/* Inverse flags */
u_int16_t invflags;
};
struct arpt_entry_target
{
union {
struct {
u_int16_t target_size;
/* Used by userspace */
char name[ARPT_FUNCTION_MAXNAMELEN];
} user;
struct {
u_int16_t target_size;
/* Used inside the kernel */
struct arpt_target *target;
} kernel;
/* Total length */
u_int16_t target_size;
} u;
unsigned char data[0];
};
struct arpt_standard_target
{
struct arpt_entry_target target;
int verdict;
};
struct arpt_counters
{
u_int64_t pcnt, bcnt; /* Packet and byte counters */
};
/* Values for "flag" field in struct arpt_ip (general arp structure).
* No flags defined yet.
*/
#define ARPT_F_MASK 0x00 /* All possible flag bits mask. */
/* Values for "inv" field in struct arpt_arp. */
#define ARPT_INV_VIA_IN 0x0001 /* Invert the sense of IN IFACE. */
#define ARPT_INV_VIA_OUT 0x0002 /* Invert the sense of OUT IFACE */
#define ARPT_INV_SRCIP 0x0004 /* Invert the sense of SRC IP. */
#define ARPT_INV_TGTIP 0x0008 /* Invert the sense of TGT IP. */
#define ARPT_INV_SRCDEVADDR 0x0010 /* Invert the sense of SRC DEV ADDR. */
#define ARPT_INV_TGTDEVADDR 0x0020 /* Invert the sense of TGT DEV ADDR. */
#define ARPT_INV_ARPOP 0x0040 /* Invert the sense of ARP OP. */
#define ARPT_INV_ARPHRD 0x0080 /* Invert the sense of ARP HRD. */
#define ARPT_INV_ARPPRO 0x0100 /* Invert the sense of ARP PRO. */
#define ARPT_INV_ARPHLN 0x0200 /* Invert the sense of ARP HLN. */
#define ARPT_INV_MASK 0x007F /* All possible flag bits mask. */
/* This structure defines each of the firewall rules. Consists of 3
parts which are 1) general ARP header stuff 2) match specific
stuff 3) the target to perform if the rule matches */
struct arpt_entry
{
struct arpt_arp arp;
/* Size of arpt_entry + matches */
u_int16_t target_offset;
/* Size of arpt_entry + matches + target */
u_int16_t next_offset;
/* Back pointer */
unsigned int comefrom;
/* Packet and byte counters. */
struct arpt_counters counters;
/* The matches (if any), then the target. */
unsigned char elems[0];
};
/*
* New IP firewall options for [gs]etsockopt at the RAW IP level.
* Unlike BSD Linux inherits IP options so you don't have to use a raw
* socket for this. Instead we check rights in the calls.
*/
#define ARPT_BASE_CTL 96 /* base for firewall socket options */
#define ARPT_SO_SET_REPLACE (ARPT_BASE_CTL)
#define ARPT_SO_SET_ADD_COUNTERS (ARPT_BASE_CTL + 1)
#define ARPT_SO_SET_MAX ARPT_SO_SET_ADD_COUNTERS
#define ARPT_SO_GET_INFO (ARPT_BASE_CTL)
#define ARPT_SO_GET_ENTRIES (ARPT_BASE_CTL + 1)
#define ARPT_SO_GET_MAX ARPT_SO_GET_ENTRIES
/* CONTINUE verdict for targets */
#define ARPT_CONTINUE 0xFFFFFFFF
/* For standard target */
#define ARPT_RETURN (-NF_MAX_VERDICT - 1)
/* The argument to ARPT_SO_GET_INFO */
struct arpt_getinfo
{
/* Which table: caller fills this in. */
char name[ARPT_TABLE_MAXNAMELEN];
/* Kernel fills these in. */
/* Which hook entry points are valid: bitmask */
unsigned int valid_hooks;
/* Hook entry points: one per netfilter hook. */
unsigned int hook_entry[NF_ARP_NUMHOOKS];
/* Underflow points. */
unsigned int underflow[NF_ARP_NUMHOOKS];
/* Number of entries */
unsigned int num_entries;
/* Size of entries. */
unsigned int size;
};
/* The argument to ARPT_SO_SET_REPLACE. */
struct arpt_replace
{
/* Which table. */
char name[ARPT_TABLE_MAXNAMELEN];
/* Which hook entry points are valid: bitmask. You can't
change this. */
unsigned int valid_hooks;
/* Number of entries */
unsigned int num_entries;
/* Total size of new entries */
unsigned int size;
/* Hook entry points. */
unsigned int hook_entry[NF_ARP_NUMHOOKS];
/* Underflow points. */
unsigned int underflow[NF_ARP_NUMHOOKS];
/* Information about old entries: */
/* Number of counters (must be equal to current number of entries). */
unsigned int num_counters;
/* The old entries' counters. */
struct arpt_counters *counters;
/* The entries (hang off end: not really an array). */
struct arpt_entry entries[0];
};
/* The argument to ARPT_SO_ADD_COUNTERS. */
struct arpt_counters_info
{
/* Which table. */
char name[ARPT_TABLE_MAXNAMELEN];
unsigned int num_counters;
/* The counters (actually `number' of these). */
struct arpt_counters counters[0];
};
/* The argument to ARPT_SO_GET_ENTRIES. */
struct arpt_get_entries
{
/* Which table: user fills this in. */
char name[ARPT_TABLE_MAXNAMELEN];
/* User fills this in: total entry size. */
unsigned int size;
/* The entries. */
struct arpt_entry entrytable[0];
};
/* Standard return verdict, or do jump. */
#define ARPT_STANDARD_TARGET ""
/* Error verdict. */
#define ARPT_ERROR_TARGET "ERROR"
/* Helper functions */
static __inline__ struct arpt_entry_target *arpt_get_target(struct arpt_entry *e)
{
return (void *)e + e->target_offset;
}
/* fn returns 0 to continue iteration */
#define ARPT_ENTRY_ITERATE(entries, size, fn, args...) \
({ \
unsigned int __i; \
int __ret = 0; \
struct arpt_entry *__entry; \
\
for (__i = 0; __i < (size); __i += __entry->next_offset) { \
__entry = (void *)(entries) + __i; \
\
__ret = fn(__entry , ## args); \
if (__ret != 0) \
break; \
} \
__ret; \
})
/*
* Main firewall chains definitions and global var's definitions.
*/
#ifdef __KERNEL__
/* Registration hooks for targets. */
struct arpt_target
{
struct list_head list;
const char name[ARPT_FUNCTION_MAXNAMELEN];
/* Returns verdict. */
unsigned int (*target)(struct sk_buff **pskb,
unsigned int hooknum,
const struct net_device *in,
const struct net_device *out,
const void *targinfo,
void *userdata);
/* Called when user tries to insert an entry of this type:
hook_mask is a bitmask of hooks from which it can be
called. */
/* Should return true or false. */
int (*checkentry)(const char *tablename,
const struct arpt_entry *e,
void *targinfo,
unsigned int targinfosize,
unsigned int hook_mask);
/* Called when entry of this type deleted. */
void (*destroy)(void *targinfo, unsigned int targinfosize);
/* Set this to THIS_MODULE if you are a module, otherwise NULL */
struct module *me;
};
extern int arpt_register_target(struct arpt_target *target);
extern void arpt_unregister_target(struct arpt_target *target);
/* Furniture shopping... */
struct arpt_table
{
struct list_head list;
/* A unique name... */
char name[ARPT_TABLE_MAXNAMELEN];
/* Seed table: copied in register_table */
struct arpt_replace *table;
/* What hooks you will enter on */
unsigned int valid_hooks;
/* Lock for the curtain */
rwlock_t lock;
/* Man behind the curtain... */
struct arpt_table_info *private;
/* Set this to THIS_MODULE if you are a module, otherwise NULL */
struct module *me;
};
extern int arpt_register_table(struct arpt_table *table);
extern void arpt_unregister_table(struct arpt_table *table);
extern unsigned int arpt_do_table(struct sk_buff **pskb,
unsigned int hook,
const struct net_device *in,
const struct net_device *out,
struct arpt_table *table,
void *userdata);
#define ARPT_ALIGN(s) (((s) + (__alignof__(struct arpt_entry)-1)) & ~(__alignof__(struct arpt_entry)-1))
#endif /*__KERNEL__*/
#endif /* _ARPTABLES_H */
include/linux/netfilter_ipv4/ip_nat.h
View file @ ff5d22a4
......@@ -11,8 +11,13 @@ enum ip_nat_manip_type
IP_NAT_MANIP_DST
};
#ifndef CONFIG_IP_NF_NAT_LOCAL
/* SRC manip occurs only on POST_ROUTING */
#define HOOK2MANIP(hooknum) ((hooknum) != NF_IP_POST_ROUTING)
#else
/* SRC manip occurs POST_ROUTING or LOCAL_IN */
#define HOOK2MANIP(hooknum) ((hooknum) != NF_IP_POST_ROUTING && (hooknum) != NF_IP_LOCAL_IN)
#endif
/* 2.3.19 (I hope) will define this in linux/netfilter_ipv4.h. */
#ifndef SO_ORIGINAL_DST
......
net/ipv4/arp.c
View file @ ff5d22a4
......@@ -112,7 +112,7 @@
#include <asm/system.h>
#include <asm/uaccess.h>
#include <linux/netfilter_arp.h>
/*
* Interface to generic neighbour cache.
......@@ -561,7 +561,8 @@ void arp_send(int type, int ptype, u32 dest_ip,
arp_ptr+=dev->addr_len;
memcpy(arp_ptr, &dest_ip, 4);
dev_queue_xmit(skb);
/* Send it off, maybe filter it using firewalling first. */
NF_HOOK(NF_ARP, NF_ARP_OUT, skb, NULL, dev, dev_queue_xmit);
return;
out:
......@@ -574,45 +575,31 @@ static void parp_redo(struct sk_buff *skb)
}
/*
* Receive an arp request by the device layer.
* Process an arp request.
*/
int arp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt)
int arp_process(struct sk_buff *skb)
{
struct arphdr *arp = skb->nh.arph;
unsigned char *arp_ptr= (unsigned char *)(arp+1);
struct net_device *dev = skb->dev;
struct in_device *in_dev = in_dev_get(dev);
struct arphdr *arp;
unsigned char *arp_ptr;
struct rtable *rt;
unsigned char *sha, *tha;
u32 sip, tip;
u16 dev_type = dev->type;
int addr_type;
struct in_device *in_dev = in_dev_get(dev);
struct neighbour *n;
/*
* The hardware length of the packet should match the hardware length
* of the device. Similarly, the hardware types should match. The
* device should be ARP-able. Also, if pln is not 4, then the lookup
* is not from an IP number. We can't currently handle this, so toss
* it.
/* arp_rcv below verifies the ARP header, verifies the device
* is ARP'able, and linearizes the SKB (if needed).
*/
if (in_dev == NULL ||
arp->ar_hln != dev->addr_len ||
dev->flags & IFF_NOARP ||
skb->pkt_type == PACKET_OTHERHOST ||
skb->pkt_type == PACKET_LOOPBACK ||
arp->ar_pln != 4)
goto out;
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
goto out_of_mem;
if (in_dev == NULL)
goto out;
if (skb_is_nonlinear(skb)) {
if (skb_linearize(skb, GFP_ATOMIC) != 0)
goto freeskb;
arp = skb->nh.arph;
arp_ptr= (unsigned char *)(arp+1);
}
switch (dev_type) {
default:
......@@ -827,13 +814,41 @@ int arp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt)
out:
if (in_dev)
in_dev_put(in_dev);
freeskb:
kfree_skb(skb);
out_of_mem:
return 0;
}
/*
* Receive an arp request from the device layer.
*/
int arp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt)
{
struct arphdr *arp = skb->nh.arph;
if (arp->ar_hln != dev->addr_len ||
dev->flags & IFF_NOARP ||
skb->pkt_type == PACKET_OTHERHOST ||
skb->pkt_type == PACKET_LOOPBACK ||
arp->ar_pln != 4)
goto freeskb;
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
goto out_of_mem;
if (skb_is_nonlinear(skb)) {
if (skb_linearize(skb, GFP_ATOMIC) != 0)
goto freeskb;
}
return NF_HOOK(NF_ARP, NF_ARP_IN, skb, dev, NULL, arp_process);
freeskb:
kfree_skb(skb);
out_of_mem:
return 0;
}
/*
* User level interface (ioctl, /proc)
......
net/ipv4/netfilter/Config.in
View file @ ff5d22a4
......@@ -47,6 +47,7 @@ if [ "$CONFIG_IP_NF_IPTABLES" != "n" ]; then
define_bool CONFIG_IP_NF_NAT_NEEDED y
dep_tristate ' MASQUERADE target support' CONFIG_IP_NF_TARGET_MASQUERADE $CONFIG_IP_NF_NAT
dep_tristate ' REDIRECT target support' CONFIG_IP_NF_TARGET_REDIRECT $CONFIG_IP_NF_NAT
bool ' NAT of local connections' CONFIG_IP_NF_NAT_LOCAL
if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
dep_tristate ' Basic SNMP-ALG support (EXPERIMENTAL)' CONFIG_IP_NF_NAT_SNMP_BASIC $CONFIG_IP_NF_NAT
fi
......@@ -79,6 +80,11 @@ if [ "$CONFIG_IP_NF_IPTABLES" != "n" ]; then
dep_tristate ' TCPMSS target support' CONFIG_IP_NF_TARGET_TCPMSS $CONFIG_IP_NF_IPTABLES
fi
tristate 'ARP tables support' CONFIG_IP_NF_ARPTABLES
if [ "$CONFIG_IP_NF_ARPTABLES" != "n" ]; then
dep_tristate ' ARP packet filtering' CONFIG_IP_NF_ARPFILTER $CONFIG_IP_NF_ARPTABLES
fi
# Backwards compatibility modules: only if you don't build in the others.
if [ "$CONFIG_IP_NF_CONNTRACK" != "y" ]; then
if [ "$CONFIG_IP_NF_IPTABLES" != "y" ]; then
......
net/ipv4/netfilter/Makefile
View file @ ff5d22a4
......@@ -9,7 +9,7 @@
O_TARGET := netfilter.o
export-objs = ip_conntrack_standalone.o ip_conntrack_ftp.o ip_fw_compat.o ip_nat_standalone.o ip_tables.o
export-objs = ip_conntrack_standalone.o ip_conntrack_ftp.o ip_fw_compat.o ip_nat_standalone.o ip_tables.o arp_tables.o
# Multipart objects.
list-multi := ip_conntrack.o iptable_nat.o ipfwadm.o ipchains.o
......@@ -75,6 +75,12 @@ obj-$(CONFIG_IP_NF_TARGET_LOG) += ipt_LOG.o
obj-$(CONFIG_IP_NF_TARGET_ULOG) += ipt_ULOG.o
obj-$(CONFIG_IP_NF_TARGET_TCPMSS) += ipt_TCPMSS.o
# generic ARP tables
obj-$(CONFIG_IP_NF_ARPTABLES) += arp_tables.o
# just filtering instance of ARP tables for now
obj-$(CONFIG_IP_NF_ARPFILTER) += arptable_filter.o
# backwards compatibility
obj-$(CONFIG_IP_NF_COMPAT_IPCHAINS) += ipchains.o
obj-$(CONFIG_IP_NF_COMPAT_IPFWADM) += ipfwadm.o
......
net/ipv4/netfilter/arp_tables.c 0 → 100644
View file @ ff5d22a4
/*
* Packet matching code for ARP packets.
*
* Based heavily, if not almost entirely, upon ip_tables.c framework.
*
* Some ARP specific bits are:
*
* Copyright (C) 2002 David S. Miller (davem@redhat.com)
*
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/kmod.h>
#include <linux/vmalloc.h>
#include <linux/proc_fs.h>
#include <linux/module.h>
#include <linux/init.h>
#include <asm/uaccess.h>
#include <asm/semaphore.h>
#include <linux/netfilter_arp/arp_tables.h>
/*#define DEBUG_ARP_TABLES*/
/*#define DEBUG_ARP_TABLES_USER*/
#ifdef DEBUG_ARP_TABLES
#define dprintf(format, args...) printk(format , ## args)
#else
#define dprintf(format, args...)
#endif
#ifdef DEBUG_ARP_TABLES_USER
#define duprintf(format, args...) printk(format , ## args)
#else
#define duprintf(format, args...)
#endif
#ifdef CONFIG_NETFILTER_DEBUG
#define ARP_NF_ASSERT(x) \
do { \
if (!(x)) \
printk("ARP_NF_ASSERT: %s:%s:%u\n", \
__FUNCTION__, __FILE__, __LINE__); \
} while(0)
#else
#define ARP_NF_ASSERT(x)
#endif
#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
static DECLARE_MUTEX(arpt_mutex);
#define ASSERT_READ_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0)
#define ASSERT_WRITE_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0)
#include <linux/netfilter_ipv4/lockhelp.h>
#include <linux/netfilter_ipv4/listhelp.h>
struct arpt_table_info {
unsigned int size;
unsigned int number;
unsigned int initial_entries;
unsigned int hook_entry[NF_ARP_NUMHOOKS];
unsigned int underflow[NF_ARP_NUMHOOKS];
char entries[0] __attribute__((aligned(SMP_CACHE_BYTES)));
};
static LIST_HEAD(arpt_target);
static LIST_HEAD(arpt_tables);
#define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0)
#ifdef CONFIG_SMP
#define TABLE_OFFSET(t,p) (SMP_ALIGN((t)->size)*(p))
#else
#define TABLE_OFFSET(t,p) 0
#endif
static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
char *hdr_addr, int len)
{
int i, ret;
if (len > ARPT_DEV_ADDR_LEN_MAX)
len = ARPT_DEV_ADDR_LEN_MAX;
ret = 0;
for (i = 0; i < len; i++)
ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i];
return (ret != 0);
}
/* Returns whether packet matches rule or not. */
static inline int arp_packet_match(const struct arphdr *arphdr,
struct net_device *dev,
const char *indev,
const char *outdev,
const struct arpt_arp *arpinfo)
{
char *arpptr = (char *)(arphdr + 1);
char *src_devaddr, *tgt_devaddr;
u32 *src_ipaddr, *tgt_ipaddr;
int i, ret;
#define FWINV(bool,invflg) ((bool) ^ !!(arpinfo->invflags & invflg))
if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop,
ARPT_INV_ARPOP)) {
dprintf("ARP operation field mismatch.\n");
dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n",
arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask);
return 0;
}
if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd,
ARPT_INV_ARPHRD)) {
dprintf("ARP hardware address format mismatch.\n");
dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n",
arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask);
return 0;
}
if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro,
ARPT_INV_ARPPRO)) {
dprintf("ARP protocol address format mismatch.\n");
dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n",
arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask);
return 0;
}
if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln,
ARPT_INV_ARPHLN)) {
dprintf("ARP hardware address length mismatch.\n");
dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n",
arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask);
}
src_devaddr = arpptr;
arpptr += dev->addr_len;
src_ipaddr = (u32 *) arpptr;
arpptr += sizeof(u32);
tgt_devaddr = arpptr;
arpptr += dev->addr_len;
tgt_ipaddr = (u32 *) arpptr;
if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len),
ARPT_INV_SRCDEVADDR) ||
FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len),
ARPT_INV_TGTDEVADDR)) {
dprintf("Source or target device address mismatch.\n");
return 0;
}
if (FWINV(((*src_ipaddr) & arpinfo->smsk.s_addr) != arpinfo->src.s_addr,
ARPT_INV_SRCIP) ||
FWINV((((*tgt_ipaddr) & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr),
ARPT_INV_TGTIP)) {
dprintf("Source or target IP address mismatch.\n");
dprintf("SRC: %u.%u.%u.%u. Mask: %u.%u.%u.%u. Target: %u.%u.%u.%u.%s\n",
NIPQUAD(*src_ipaddr),
NIPQUAD(arpinfo->smsk.s_addr),
NIPQUAD(arpinfo->src.s_addr),
arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : "");
dprintf("TGT: %u.%u.%u.%u Mask: %u.%u.%u.%u Target: %u.%u.%u.%u.%s\n",
NIPQUAD(*tgt_ipaddr),
NIPQUAD(arpinfo->tmsk.s_addr),
NIPQUAD(arpinfo->tgt.s_addr),
arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : "");
return 0;
}
/* Look for ifname matches; this should unroll nicely. */
for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
ret |= (((const unsigned long *)indev)[i]
^ ((const unsigned long *)arpinfo->iniface)[i])
& ((const unsigned long *)arpinfo->iniface_mask)[i];
}
if (FWINV(ret != 0, ARPT_INV_VIA_IN)) {
dprintf("VIA in mismatch (%s vs %s).%s\n",
indev, arpinfo->iniface,
arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":"");
return 0;
}
for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
ret |= (((const unsigned long *)outdev)[i]
^ ((const unsigned long *)arpinfo->outiface)[i])
& ((const unsigned long *)arpinfo->outiface_mask)[i];
}
if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) {
dprintf("VIA out mismatch (%s vs %s).%s\n",
outdev, arpinfo->outiface,
arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":"");
return 0;
}
return 1;
}
static inline int arp_checkentry(const struct arpt_arp *arp)
{
if (arp->flags & ~ARPT_F_MASK) {
duprintf("Unknown flag bits set: %08X\n",
arp->flags & ~ARPT_F_MASK);
return 0;
}
if (arp->invflags & ~ARPT_INV_MASK) {
duprintf("Unknown invflag bits set: %08X\n",
arp->invflags & ~ARPT_INV_MASK);
return 0;
}
return 1;
}
static unsigned int arpt_error(struct sk_buff **pskb,
unsigned int hooknum,
const struct net_device *in,
const struct net_device *out,
const void *targinfo,
void *userinfo)
{
if (net_ratelimit())
printk("arp_tables: error: '%s'\n", (char *)targinfo);
return NF_DROP;
}
static inline struct arpt_entry *get_entry(void *base, unsigned int offset)
{
return (struct arpt_entry *)(base + offset);
}
unsigned int arpt_do_table(struct sk_buff **pskb,
unsigned int hook,
const struct net_device *in,
const struct net_device *out,
struct arpt_table *table,
void *userdata)
{
static const char nulldevname[IFNAMSIZ] = { 0 };
unsigned int verdict = NF_DROP;
struct arphdr *arp = (*pskb)->nh.arph;
int hotdrop = 0;
struct arpt_entry *e, *back;
const char *indev, *outdev;
void *table_base;
indev = in ? in->name : nulldevname;
outdev = out ? out->name : nulldevname;
read_lock_bh(&table->lock);
table_base = (void *)table->private->entries
+ TABLE_OFFSET(table->private,
cpu_number_map(smp_processor_id()));
e = get_entry(table_base, table->private->hook_entry[hook]);
back = get_entry(table_base, table->private->underflow[hook]);
do {
if (arp_packet_match(arp, (*pskb)->dev, indev, outdev, &e->arp)) {
struct arpt_entry_target *t;
int hdr_len;
hdr_len = sizeof(*arp) + (2 * sizeof(struct in_addr)) +
(2 * (*pskb)->dev->addr_len);
ADD_COUNTER(e->counters, hdr_len, 1);
t = arpt_get_target(e);
/* Standard target? */
if (!t->u.kernel.target->target) {
int v;
v = ((struct arpt_standard_target *)t)->verdict;
if (v < 0) {
/* Pop from stack? */
if (v != ARPT_RETURN) {
verdict = (unsigned)(-v) - 1;
break;
}
e = back;
back = get_entry(table_base,
back->comefrom);
continue;
}
if (table_base + v
!= (void *)e + e->next_offset) {
/* Save old back ptr in next entry */
struct arpt_entry *next
= (void *)e + e->next_offset;
next->comefrom =
(void *)back - table_base;
/* set back pointer to next entry */
back = next;
}
e = get_entry(table_base, v);
} else {
/* Targets which reenter must return
* abs. verdicts
*/
verdict = t->u.kernel.target->target(pskb,
hook,
in, out,
t->data,
userdata);
/* Target might have changed stuff. */
arp = (*pskb)->nh.arph;
if (verdict == ARPT_CONTINUE)
e = (void *)e + e->next_offset;
else
/* Verdict */
break;
}
} else {
e = (void *)e + e->next_offset;
}
} while (!hotdrop);
read_unlock_bh(&table->lock);
if (hotdrop)
return NF_DROP;
else
return verdict;
}
static inline void *find_inlist_lock_noload(struct list_head *head,
const char *name,
int *error,
struct semaphore *mutex)
{
void *ret;
*error = down_interruptible(mutex);
if (*error != 0)
return NULL;
ret = list_named_find(head, name);
if (!ret) {
*error = -ENOENT;
up(mutex);
}
return ret;
}
#ifndef CONFIG_KMOD
#define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m))
#else
static void *
find_inlist_lock(struct list_head *head,
const char *name,
const char *prefix,
int *error,
struct semaphore *mutex)
{
void *ret;
ret = find_inlist_lock_noload(head, name, error, mutex);
if (!ret) {
char modulename[ARPT_FUNCTION_MAXNAMELEN + strlen(prefix) + 1];
strcpy(modulename, prefix);
strcat(modulename, name);
duprintf("find_inlist: loading `%s'.\n", modulename);
request_module(modulename);
ret = find_inlist_lock_noload(head, name, error, mutex);
}
return ret;
}
#endif
static inline struct arpt_table *find_table_lock(const char *name, int *error, struct semaphore *mutex)
{
return find_inlist_lock(&arpt_tables, name, "arptable_", error, mutex);
}
static inline struct arpt_target *find_target_lock(const char *name, int *error, struct semaphore *mutex)
{
return find_inlist_lock(&arpt_target, name, "arpt_", error, mutex);
}
/* All zeroes == unconditional rule. */
static inline int unconditional(const struct arpt_arp *arp)
{
unsigned int i;
for (i = 0; i < sizeof(*arp)/sizeof(__u32); i++)
if (((__u32 *)arp)[i])
return 0;
return 1;
}
/* Figures out from what hook each rule can be called: returns 0 if
* there are loops. Puts hook bitmask in comefrom.
*/
static int mark_source_chains(struct arpt_table_info *newinfo, unsigned int valid_hooks)
{
unsigned int hook;
/* No recursion; use packet counter to save back ptrs (reset
* to 0 as we leave), and comefrom to save source hook bitmask.
*/
for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
unsigned int pos = newinfo->hook_entry[hook];
struct arpt_entry *e
= (struct arpt_entry *)(newinfo->entries + pos);
if (!(valid_hooks & (1 << hook)))
continue;
/* Set initial back pointer. */
e->counters.pcnt = pos;
for (;;) {
struct arpt_standard_target *t
= (void *)arpt_get_target(e);
if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
printk("arptables: loop hook %u pos %u %08X.\n",
hook, pos, e->comefrom);
return 0;
}
e->comefrom
|= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
/* Unconditional return/END. */
if (e->target_offset == sizeof(struct arpt_entry)
&& (strcmp(t->target.u.user.name,
ARPT_STANDARD_TARGET) == 0)
&& t->verdict < 0
&& unconditional(&e->arp)) {
unsigned int oldpos, size;
/* Return: backtrack through the last
* big jump.
*/
do {
e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
oldpos = pos;
pos = e->counters.pcnt;
e->counters.pcnt = 0;
/* We're at the start. */
if (pos == oldpos)
goto next;
e = (struct arpt_entry *)
(newinfo->entries + pos);
} while (oldpos == pos + e->next_offset);
/* Move along one */
size = e->next_offset;
e = (struct arpt_entry *)
(newinfo->entries + pos + size);
e->counters.pcnt = pos;
pos += size;
} else {
int newpos = t->verdict;
if (strcmp(t->target.u.user.name,
ARPT_STANDARD_TARGET) == 0
&& newpos >= 0) {
/* This a jump; chase it. */
duprintf("Jump rule %u -> %u\n",
pos, newpos);
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;
}
e = (struct arpt_entry *)
(newinfo->entries + newpos);
e->counters.pcnt = pos;
pos = newpos;
}
}
next:
duprintf("Finished chain %u\n", hook);
}
return 1;
}
static inline int standard_check(const struct arpt_entry_target *t,
unsigned int max_offset)
{
struct arpt_standard_target *targ = (void *)t;
/* Check standard info. */
if (t->u.target_size
!= ARPT_ALIGN(sizeof(struct arpt_standard_target))) {
duprintf("arpt_standard_check: target size %u != %Zu\n",
t->u.target_size,
ARPT_ALIGN(sizeof(struct arpt_standard_target)));
return 0;
}
if (targ->verdict >= 0
&& targ->verdict > max_offset - sizeof(struct arpt_entry)) {
duprintf("arpt_standard_check: bad verdict (%i)\n",
targ->verdict);
return 0;
}
if (targ->verdict < -NF_MAX_VERDICT - 1) {
duprintf("arpt_standard_check: bad negative verdict (%i)\n",
targ->verdict);
return 0;
}
return 1;
}
static struct arpt_target arpt_standard_target;
static inline int check_entry(struct arpt_entry *e, const char *name, unsigned int size,
unsigned int *i)
{
struct arpt_entry_target *t;
struct arpt_target *target;
int ret;
if (!arp_checkentry(&e->arp)) {
duprintf("arp_tables: arp check failed %p %s.\n", e, name);
return -EINVAL;
}
t = arpt_get_target(e);
target = find_target_lock(t->u.user.name, &ret, &arpt_mutex);
if (!target) {
duprintf("check_entry: `%s' not found\n", t->u.user.name);
goto out;
}
if (target->me)
__MOD_INC_USE_COUNT(target->me);
t->u.kernel.target = target;
up(&arpt_mutex);
if (t->u.kernel.target == &arpt_standard_target) {
if (!standard_check(t, size)) {
ret = -EINVAL;
goto out;
}
} else if (t->u.kernel.target->checkentry
&& !t->u.kernel.target->checkentry(name, e, t->data,
t->u.target_size
- sizeof(*t),
e->comefrom)) {
if (t->u.kernel.target->me)
__MOD_DEC_USE_COUNT(t->u.kernel.target->me);
duprintf("arp_tables: check failed for `%s'.\n",
t->u.kernel.target->name);
ret = -EINVAL;
goto out;
}
(*i)++;
return 0;
out:
return ret;
}
static inline int check_entry_size_and_hooks(struct arpt_entry *e,
struct arpt_table_info *newinfo,
unsigned char *base,
unsigned char *limit,
const unsigned int *hook_entries,
const unsigned int *underflows,
unsigned int *i)
{
unsigned int h;
if ((unsigned long)e % __alignof__(struct arpt_entry) != 0
|| (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
duprintf("Bad offset %p\n", e);
return -EINVAL;
}
if (e->next_offset
< sizeof(struct arpt_entry) + sizeof(struct arpt_entry_target)) {
duprintf("checking: element %p size %u\n",
e, e->next_offset);
return -EINVAL;
}
/* Check hooks & underflows */
for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
if ((unsigned char *)e - base == hook_entries[h])
newinfo->hook_entry[h] = hook_entries[h];
if ((unsigned char *)e - base == underflows[h])
newinfo->underflow[h] = underflows[h];
}
/* FIXME: underflows must be unconditional, standard verdicts
< 0 (not ARPT_RETURN). --RR */
/* Clear counters and comefrom */
e->counters = ((struct arpt_counters) { 0, 0 });
e->comefrom = 0;
(*i)++;
return 0;
}
static inline int cleanup_entry(struct arpt_entry *e, unsigned int *i)
{
struct arpt_entry_target *t;
if (i && (*i)-- == 0)
return 1;
t = arpt_get_target(e);
if (t->u.kernel.target->destroy)
t->u.kernel.target->destroy(t->data,
t->u.target_size - sizeof(*t));
if (t->u.kernel.target->me)
__MOD_DEC_USE_COUNT(t->u.kernel.target->me);
return 0;
}
/* Checks and translates the user-supplied table segment (held in
* newinfo).
*/
static int translate_table(const char *name,
unsigned int valid_hooks,
struct arpt_table_info *newinfo,
unsigned int size,
unsigned int number,
const unsigned int *hook_entries,
const unsigned int *underflows)
{
unsigned int i;
int ret;
newinfo->size = size;
newinfo->number = number;
/* Init all hooks to impossible value. */
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
newinfo->hook_entry[i] = 0xFFFFFFFF;
newinfo->underflow[i] = 0xFFFFFFFF;
}
duprintf("translate_table: size %u\n", newinfo->size);
i = 0;
/* Walk through entries, checking offsets. */
ret = ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size,
check_entry_size_and_hooks,
newinfo,
newinfo->entries,
newinfo->entries + size,
hook_entries, underflows, &i);
duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret);
if (ret != 0)
return ret;
if (i != number) {
duprintf("translate_table: %u not %u entries\n",
i, number);
return -EINVAL;
}
/* Check hooks all assigned */
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
/* Only hooks which are valid */
if (!(valid_hooks & (1 << i)))
continue;
if (newinfo->hook_entry[i] == 0xFFFFFFFF) {
duprintf("Invalid hook entry %u %u\n",
i, hook_entries[i]);
return -EINVAL;
}
if (newinfo->underflow[i] == 0xFFFFFFFF) {
duprintf("Invalid underflow %u %u\n",
i, underflows[i]);
return -EINVAL;
}
}
if (!mark_source_chains(newinfo, valid_hooks)) {
duprintf("Looping hook\n");
return -ELOOP;
}
/* Finally, each sanity check must pass */
i = 0;
ret = ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size,
check_entry, name, size, &i);
if (ret != 0) {
ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size,
cleanup_entry, &i);
return ret;
}
/* And one copy for every other CPU */
for (i = 1; i < smp_num_cpus; i++) {
memcpy(newinfo->entries + SMP_ALIGN(newinfo->size)*i,
newinfo->entries,
SMP_ALIGN(newinfo->size));
}
return ret;
}
static struct arpt_table_info *replace_table(struct arpt_table *table,
unsigned int num_counters,
struct arpt_table_info *newinfo,
int *error)
{
struct arpt_table_info *oldinfo;
/* Do the substitution. */
write_lock_bh(&table->lock);
/* Check inside lock: is the old number correct? */
if (num_counters != table->private->number) {
duprintf("num_counters != table->private->number (%u/%u)\n",
num_counters, table->private->number);
write_unlock_bh(&table->lock);
*error = -EAGAIN;
return NULL;
}
oldinfo = table->private;
table->private = newinfo;
newinfo->initial_entries = oldinfo->initial_entries;
write_unlock_bh(&table->lock);
return oldinfo;
}
/* Gets counters. */
static inline int add_entry_to_counter(const struct arpt_entry *e,
struct arpt_counters total[],
unsigned int *i)
{
ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt);
(*i)++;
return 0;
}
static void get_counters(const struct arpt_table_info *t,
struct arpt_counters counters[])
{
unsigned int cpu;
unsigned int i;
for (cpu = 0; cpu < smp_num_cpus; cpu++) {
i = 0;
ARPT_ENTRY_ITERATE(t->entries + TABLE_OFFSET(t, cpu),
t->size,
add_entry_to_counter,
counters,
&i);
}
}
static int copy_entries_to_user(unsigned int total_size,
struct arpt_table *table,
void *userptr)
{
unsigned int off, num, countersize;
struct arpt_entry *e;
struct arpt_counters *counters;
int ret = 0;
/* We need atomic snapshot of counters: rest doesn't change
* (other than comefrom, which userspace doesn't care
* about).
*/
countersize = sizeof(struct arpt_counters) * table->private->number;
counters = vmalloc(countersize);
if (counters == NULL)
return -ENOMEM;
/* First, sum counters... */
memset(counters, 0, countersize);
write_lock_bh(&table->lock);
get_counters(table->private, counters);
write_unlock_bh(&table->lock);
/* ... then copy entire thing from CPU 0... */
if (copy_to_user(userptr, table->private->entries, total_size) != 0) {
ret = -EFAULT;
goto free_counters;
}
/* FIXME: use iterator macros --RR */
/* ... then go back and fix counters and names */
for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
struct arpt_entry_target *t;
e = (struct arpt_entry *)(table->private->entries + off);
if (copy_to_user(userptr + off
+ offsetof(struct arpt_entry, counters),
&counters[num],
sizeof(counters[num])) != 0) {
ret = -EFAULT;
goto free_counters;
}
t = arpt_get_target(e);
if (copy_to_user(userptr + off + e->target_offset
+ offsetof(struct arpt_entry_target,
u.user.name),
t->u.kernel.target->name,
strlen(t->u.kernel.target->name)+1) != 0) {
ret = -EFAULT;
goto free_counters;
}
}
free_counters:
vfree(counters);
return ret;
}
static int get_entries(const struct arpt_get_entries *entries,
struct arpt_get_entries *uptr)
{
int ret;
struct arpt_table *t;
t = find_table_lock(entries->name, &ret, &arpt_mutex);
if (t) {
duprintf("t->private->number = %u\n",
t->private->number);
if (entries->size == t->private->size)
ret = copy_entries_to_user(t->private->size,
t, uptr->entrytable);
else {
duprintf("get_entries: I've got %u not %u!\n",
t->private->size,
entries->size);
ret = -EINVAL;
}
up(&arpt_mutex);
} else
duprintf("get_entries: Can't find %s!\n",
entries->name);
return ret;
}
static int do_replace(void *user, unsigned int len)
{
int ret;
struct arpt_replace tmp;
struct arpt_table *t;
struct arpt_table_info *newinfo, *oldinfo;
struct arpt_counters *counters;
if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
return -EFAULT;
/* Hack: Causes ipchains to give correct error msg --RR */
if (len != sizeof(tmp) + tmp.size)
return -ENOPROTOOPT;
/* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
if ((SMP_ALIGN(tmp.size) >> PAGE_SHIFT) + 2 > num_physpages)
return -ENOMEM;
newinfo = vmalloc(sizeof(struct arpt_table_info)
+ SMP_ALIGN(tmp.size) * smp_num_cpus);
if (!newinfo)
return -ENOMEM;
if (copy_from_user(newinfo->entries, user + sizeof(tmp),
tmp.size) != 0) {
ret = -EFAULT;
goto free_newinfo;
}
counters = vmalloc(tmp.num_counters * sizeof(struct arpt_counters));
if (!counters) {
ret = -ENOMEM;
goto free_newinfo;
}
memset(counters, 0, tmp.num_counters * sizeof(struct arpt_counters));
ret = translate_table(tmp.name, tmp.valid_hooks,
newinfo, tmp.size, tmp.num_entries,
tmp.hook_entry, tmp.underflow);
if (ret != 0)
goto free_newinfo_counters;
duprintf("arp_tables: Translated table\n");
t = find_table_lock(tmp.name, &ret, &arpt_mutex);
if (!t)
goto free_newinfo_counters_untrans;
/* You lied! */
if (tmp.valid_hooks != t->valid_hooks) {
duprintf("Valid hook crap: %08X vs %08X\n",
tmp.valid_hooks, t->valid_hooks);
ret = -EINVAL;
goto free_newinfo_counters_untrans_unlock;
}
oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret);
if (!oldinfo)
goto free_newinfo_counters_untrans_unlock;
/* Update module usage count based on number of rules */
duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n",
oldinfo->number, oldinfo->initial_entries, newinfo->number);
if (t->me && (oldinfo->number <= oldinfo->initial_entries) &&
(newinfo->number > oldinfo->initial_entries))
__MOD_INC_USE_COUNT(t->me);
else if (t->me && (oldinfo->number > oldinfo->initial_entries) &&
(newinfo->number <= oldinfo->initial_entries))
__MOD_DEC_USE_COUNT(t->me);
/* Get the old counters. */
get_counters(oldinfo, counters);
/* Decrease module usage counts and free resource */
ARPT_ENTRY_ITERATE(oldinfo->entries, oldinfo->size, cleanup_entry,NULL);
vfree(oldinfo);
/* Silent error: too late now. */
copy_to_user(tmp.counters, counters,
sizeof(struct arpt_counters) * tmp.num_counters);
vfree(counters);
up(&arpt_mutex);
return 0;
free_newinfo_counters_untrans_unlock:
up(&arpt_mutex);
free_newinfo_counters_untrans:
ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size, cleanup_entry, NULL);
free_newinfo_counters:
vfree(counters);
free_newinfo:
vfree(newinfo);
return ret;
}
/* We're lazy, and add to the first CPU; overflow works its fey magic
* and everything is OK.
*/
static inline int add_counter_to_entry(struct arpt_entry *e,
const struct arpt_counters addme[],
unsigned int *i)
{
ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt);
(*i)++;
return 0;
}
static int do_add_counters(void *user, unsigned int len)
{
unsigned int i;
struct arpt_counters_info tmp, *paddc;
struct arpt_table *t;
int ret;
if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
return -EFAULT;
if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct arpt_counters))
return -EINVAL;
paddc = vmalloc(len);
if (!paddc)
return -ENOMEM;
if (copy_from_user(paddc, user, len) != 0) {
ret = -EFAULT;
goto free;
}
t = find_table_lock(tmp.name, &ret, &arpt_mutex);
if (!t)
goto free;
write_lock_bh(&t->lock);
if (t->private->number != paddc->num_counters) {
ret = -EINVAL;
goto unlock_up_free;
}
i = 0;
ARPT_ENTRY_ITERATE(t->private->entries,
t->private->size,
add_counter_to_entry,
paddc->counters,
&i);
unlock_up_free:
write_unlock_bh(&t->lock);
up(&arpt_mutex);
free:
vfree(paddc);
return ret;
}
static int do_arpt_set_ctl(struct sock *sk, int cmd, void *user, unsigned int len)
{
int ret;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
switch (cmd) {
case ARPT_SO_SET_REPLACE:
ret = do_replace(user, len);
break;
case ARPT_SO_SET_ADD_COUNTERS:
ret = do_add_counters(user, len);
break;
default:
duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
ret = -EINVAL;
}
return ret;
}
static int do_arpt_get_ctl(struct sock *sk, int cmd, void *user, int *len)
{
int ret;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
switch (cmd) {
case ARPT_SO_GET_INFO: {
char name[ARPT_TABLE_MAXNAMELEN];
struct arpt_table *t;
if (*len != sizeof(struct arpt_getinfo)) {
duprintf("length %u != %Zu\n", *len,
sizeof(struct arpt_getinfo));
ret = -EINVAL;
break;
}
if (copy_from_user(name, user, sizeof(name)) != 0) {
ret = -EFAULT;
break;
}
name[ARPT_TABLE_MAXNAMELEN-1] = '\0';
t = find_table_lock(name, &ret, &arpt_mutex);
if (t) {
struct arpt_getinfo info;
info.valid_hooks = t->valid_hooks;
memcpy(info.hook_entry, t->private->hook_entry,
sizeof(info.hook_entry));
memcpy(info.underflow, t->private->underflow,
sizeof(info.underflow));
info.num_entries = t->private->number;
info.size = t->private->size;
strcpy(info.name, name);
if (copy_to_user(user, &info, *len) != 0)
ret = -EFAULT;
else
ret = 0;
up(&arpt_mutex);
}
}
break;
case ARPT_SO_GET_ENTRIES: {
struct arpt_get_entries get;
if (*len < sizeof(get)) {
duprintf("get_entries: %u < %Zu\n", *len, sizeof(get));
ret = -EINVAL;
} else if (copy_from_user(&get, user, sizeof(get)) != 0) {
ret = -EFAULT;
} else if (*len != sizeof(struct arpt_get_entries) + get.size) {
duprintf("get_entries: %u != %Zu\n", *len,
sizeof(struct arpt_get_entries) + get.size);
ret = -EINVAL;
} else
ret = get_entries(&get, user);
break;
}
default:
duprintf("do_arpt_get_ctl: unknown request %i\n", cmd);
ret = -EINVAL;
}
return ret;
}
/* Registration hooks for targets. */
int arpt_register_target(struct arpt_target *target)
{
int ret;
MOD_INC_USE_COUNT;
ret = down_interruptible(&arpt_mutex);
if (ret != 0) {
MOD_DEC_USE_COUNT;
return ret;
}
if (!list_named_insert(&arpt_target, target)) {
duprintf("arpt_register_target: `%s' already in list!\n",
target->name);
ret = -EINVAL;
MOD_DEC_USE_COUNT;
}
up(&arpt_mutex);
return ret;
}
void arpt_unregister_target(struct arpt_target *target)
{
down(&arpt_mutex);
LIST_DELETE(&arpt_target, target);
up(&arpt_mutex);
MOD_DEC_USE_COUNT;
}
int arpt_register_table(struct arpt_table *table)
{
int ret;
struct arpt_table_info *newinfo;
static struct arpt_table_info bootstrap
= { 0, 0, 0, { 0 }, { 0 }, { } };
MOD_INC_USE_COUNT;
newinfo = vmalloc(sizeof(struct arpt_table_info)
+ SMP_ALIGN(table->table->size) * smp_num_cpus);
if (!newinfo) {
ret = -ENOMEM;
MOD_DEC_USE_COUNT;
return ret;
}
memcpy(newinfo->entries, table->table->entries, table->table->size);
ret = translate_table(table->name, table->valid_hooks,
newinfo, table->table->size,
table->table->num_entries,
table->table->hook_entry,
table->table->underflow);
duprintf("arpt_register_table: translate table gives %d\n", ret);
if (ret != 0) {
vfree(newinfo);
MOD_DEC_USE_COUNT;
return ret;
}
ret = down_interruptible(&arpt_mutex);
if (ret != 0) {
vfree(newinfo);
MOD_DEC_USE_COUNT;
return ret;
}
/* Don't autoload: we'd eat our tail... */
if (list_named_find(&arpt_tables, table->name)) {
ret = -EEXIST;
goto free_unlock;
}
/* Simplifies replace_table code. */
table->private = &bootstrap;
if (!replace_table(table, 0, newinfo, &ret))
goto free_unlock;
duprintf("table->private->number = %u\n",
table->private->number);
/* save number of initial entries */
table->private->initial_entries = table->private->number;
table->lock = RW_LOCK_UNLOCKED;
list_prepend(&arpt_tables, table);
unlock:
up(&arpt_mutex);
return ret;
free_unlock:
vfree(newinfo);
MOD_DEC_USE_COUNT;
goto unlock;
}
void arpt_unregister_table(struct arpt_table *table)
{
down(&arpt_mutex);
LIST_DELETE(&arpt_tables, table);
up(&arpt_mutex);
/* Decrease module usage counts and free resources */
ARPT_ENTRY_ITERATE(table->private->entries, table->private->size,
cleanup_entry, NULL);
vfree(table->private);
MOD_DEC_USE_COUNT;
}
/* The built-in targets: standard (NULL) and error. */
static struct arpt_target arpt_standard_target
= { { NULL, NULL }, ARPT_STANDARD_TARGET, NULL, NULL, NULL };
static struct arpt_target arpt_error_target
= { { NULL, NULL }, ARPT_ERROR_TARGET, arpt_error, NULL, NULL };
static struct nf_sockopt_ops arpt_sockopts
= { { NULL, NULL }, PF_INET, ARPT_BASE_CTL, ARPT_SO_SET_MAX+1, do_arpt_set_ctl,
ARPT_BASE_CTL, ARPT_SO_GET_MAX+1, do_arpt_get_ctl, 0, NULL };
#ifdef CONFIG_PROC_FS
static inline int print_name(const struct arpt_table *t,
off_t start_offset, char *buffer, int length,
off_t *pos, unsigned int *count)
{
if ((*count)++ >= start_offset) {
unsigned int namelen;
namelen = sprintf(buffer + *pos, "%s\n", t->name);
if (*pos + namelen > length) {
/* Stop iterating */
return 1;
}
*pos += namelen;
}
return 0;
}
static int arpt_get_tables(char *buffer, char **start, off_t offset, int length)
{
off_t pos = 0;
unsigned int count = 0;
if (down_interruptible(&arpt_mutex) != 0)
return 0;
LIST_FIND(&arpt_tables, print_name, struct arpt_table *,
offset, buffer, length, &pos, &count);
up(&arpt_mutex);
/* `start' hack - see fs/proc/generic.c line ~105 */
*start=(char *)((unsigned long)count-offset);
return pos;
}
#endif /*CONFIG_PROC_FS*/
static int __init init(void)
{
int ret;
/* Noone else will be downing sem now, so we won't sleep */
down(&arpt_mutex);
list_append(&arpt_target, &arpt_standard_target);
list_append(&arpt_target, &arpt_error_target);
up(&arpt_mutex);
/* Register setsockopt */
ret = nf_register_sockopt(&arpt_sockopts);
if (ret < 0) {
duprintf("Unable to register sockopts.\n");
return ret;
}
#ifdef CONFIG_PROC_FS
{
struct proc_dir_entry *proc;
proc = proc_net_create("arp_tables_names", 0, arpt_get_tables);
if (!proc) {
nf_unregister_sockopt(&arpt_sockopts);
return -ENOMEM;
}
proc->owner = THIS_MODULE;
}
#endif
printk("arp_tables: (C) 2002 David S. Miller\n");
return 0;
}
static void __exit fini(void)
{
nf_unregister_sockopt(&arpt_sockopts);
#ifdef CONFIG_PROC_FS
proc_net_remove("arp_tables_names");
#endif
}
EXPORT_SYMBOL(arpt_register_table);
EXPORT_SYMBOL(arpt_unregister_table);
EXPORT_SYMBOL(arpt_do_table);
EXPORT_SYMBOL(arpt_register_target);
EXPORT_SYMBOL(arpt_unregister_target);
module_init(init);
module_exit(fini);
MODULE_LICENSE("GPL");
net/ipv4/netfilter/arptable_filter.c 0 → 100644
View file @ ff5d22a4
/*
* Filtering ARP tables module.
*
* Copyright (C) 2002 David S. Miller (davem@redhat.com)
*
*/
#include <linux/module.h>
#include <linux/netfilter_arp/arp_tables.h>
#define FILTER_VALID_HOOKS ((1 << NF_ARP_IN) | (1 << NF_ARP_OUT))
/* Standard entry. */
struct arpt_standard
{
struct arpt_entry entry;
struct arpt_standard_target target;
};
struct arpt_error_target
{
struct arpt_entry_target target;
char errorname[ARPT_FUNCTION_MAXNAMELEN];
};
struct arpt_error
{
struct arpt_entry entry;
struct arpt_error_target target;
};
static struct
{
struct arpt_replace repl;
struct arpt_standard entries[2];
struct arpt_error term;
} initial_table __initdata
= { { "filter", FILTER_VALID_HOOKS, 3,
sizeof(struct arpt_standard) * 2 + sizeof(struct arpt_error),
{ [NF_ARP_IN] 0,
[NF_ARP_OUT] sizeof(struct arpt_standard) },
{ [NF_ARP_IN] 0,
[NF_ARP_OUT] sizeof(struct arpt_standard), },
0, NULL, { } },
{
/* ARP_IN */
{
{
{
{ 0 }, { 0 }, { 0 }, { 0 },
0, 0,
{ { 0, }, { 0, } },
{ { 0, }, { 0, } },
0, 0,
0, 0,
0, 0,
"", "", { 0 }, { 0 },
0, 0
},
sizeof(struct arpt_entry),
sizeof(struct arpt_standard),
0,
{ 0, 0 }, { } },
{ { { { ARPT_ALIGN(sizeof(struct arpt_standard_target)), "" } }, { } },
-NF_ACCEPT - 1 }
},
/* ARP_OUT */
{
{
{
{ 0 }, { 0 }, { 0 }, { 0 },
0, 0,
{ { 0, }, { 0, } },
{ { 0, }, { 0, } },
0, 0,
0, 0,
0, 0,
"", "", { 0 }, { 0 },
0, 0
},
sizeof(struct arpt_entry),
sizeof(struct arpt_standard),
0,
{ 0, 0 }, { } },
{ { { { ARPT_ALIGN(sizeof(struct arpt_standard_target)), "" } }, { } },
-NF_ACCEPT - 1 }
}
},
/* ERROR */
{
{
{
{ 0 }, { 0 }, { 0 }, { 0 },
0, 0,
{ { 0, }, { 0, } },
{ { 0, }, { 0, } },
0, 0,
0, 0,
0, 0,
"", "", { 0 }, { 0 },
0, 0
},
sizeof(struct arpt_entry),
sizeof(struct arpt_error),
0,
{ 0, 0 }, { } },
{ { { { ARPT_ALIGN(sizeof(struct arpt_error_target)), ARPT_ERROR_TARGET } },
{ } },
"ERROR"
}
}
};
static struct arpt_table packet_filter
= { { NULL, NULL }, "filter", &initial_table.repl,
FILTER_VALID_HOOKS, RW_LOCK_UNLOCKED, NULL, THIS_MODULE };
/* The work comes in here from netfilter.c */
static unsigned int arpt_hook(unsigned int hook,
struct sk_buff **pskb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
return arpt_do_table(pskb, hook, in, out, &packet_filter, NULL);
}
static struct nf_hook_ops arpt_ops[]
= { { { NULL, NULL }, arpt_hook, NF_ARP, NF_ARP_IN, 0 },
{ { NULL, NULL }, arpt_hook, NF_ARP, NF_ARP_OUT, 0 }
};
static int __init init(void)
{
int ret;
/* Register table */
ret = arpt_register_table(&packet_filter);
if (ret < 0)
return ret;
/* Register hooks */
ret = nf_register_hook(&arpt_ops[0]);
if (ret < 0)
goto cleanup_table;
ret = nf_register_hook(&arpt_ops[1]);
if (ret < 0)
goto cleanup_hook0;
return ret;
cleanup_hook0:
nf_unregister_hook(&arpt_ops[0]);
cleanup_table:
arpt_unregister_table(&packet_filter);
return ret;
}
static void __exit fini(void)
{
unsigned int i;
for (i = 0; i < sizeof(arpt_ops)/sizeof(struct nf_hook_ops); i++)
nf_unregister_hook(&arpt_ops[i]);
arpt_unregister_table(&packet_filter);
}
module_init(init);
module_exit(fini);
MODULE_LICENSE("GPL");
net/ipv4/netfilter/ip_conntrack_standalone.c
View file @ ff5d22a4
......@@ -15,6 +15,7 @@
#include <linux/skbuff.h>
#include <linux/proc_fs.h>
#include <linux/version.h>
#include <linux/brlock.h>
#include <net/checksum.h>
#define ASSERT_READ_LOCK(x) MUST_BE_READ_LOCKED(&ip_conntrack_lock)
......@@ -35,6 +36,11 @@
struct module *ip_conntrack_module = THIS_MODULE;
MODULE_LICENSE("GPL");
static int kill_proto(const struct ip_conntrack *i, void *data)
{
return (i->tuplehash[IP_CT_DIR_ORIGINAL].dst.protonum ==
*((u_int8_t *) data));
}
static unsigned int
print_tuple(char *buffer, const struct ip_conntrack_tuple *tuple,
......@@ -304,12 +310,24 @@ int ip_conntrack_protocol_register(struct ip_conntrack_protocol *proto)
return ret;
}
/* FIXME: Implement this --RR */
#if 0
void ip_conntrack_protocol_unregister(struct ip_conntrack_protocol *proto)
{
WRITE_LOCK(&ip_conntrack_lock);
/* find_proto() returns proto_generic in case there is no protocol
* helper. So this should be enough - HW */
LIST_DELETE(&protocol_list, proto);
WRITE_UNLOCK(&ip_conntrack_lock);
/* Somebody could be still looking at the proto in bh. */
br_write_lock_bh(BR_NETPROTO_LOCK);
br_write_unlock_bh(BR_NETPROTO_LOCK);
/* Remove all contrack entries for this protocol */
ip_ct_selective_cleanup(kill_proto, &proto->proto);
MOD_DEC_USE_COUNT;
}
#endif
static int __init init(void)
{
......@@ -325,6 +343,7 @@ module_init(init);
module_exit(fini);
EXPORT_SYMBOL(ip_conntrack_protocol_register);
EXPORT_SYMBOL(ip_conntrack_protocol_unregister);
EXPORT_SYMBOL(invert_tuplepr);
EXPORT_SYMBOL(ip_conntrack_alter_reply);
EXPORT_SYMBOL(ip_conntrack_destroyed);
......@@ -335,6 +354,7 @@ EXPORT_SYMBOL(ip_conntrack_helper_unregister);
EXPORT_SYMBOL(ip_ct_selective_cleanup);
EXPORT_SYMBOL(ip_ct_refresh);
EXPORT_SYMBOL(ip_conntrack_expect_related);
EXPORT_SYMBOL(ip_conntrack_unexpect_related);
EXPORT_SYMBOL(ip_conntrack_tuple_taken);
EXPORT_SYMBOL(ip_ct_gather_frags);
EXPORT_SYMBOL(ip_conntrack_htable_size);
net/ipv4/netfilter/ip_nat_core.c
View file @ ff5d22a4
......@@ -314,6 +314,7 @@ find_best_ips_proto(struct ip_conntrack_tuple *tuple,
* do_extra_mangle last time. */
*other_ipp = saved_ip;
#ifdef CONFIG_IP_NF_NAT_LOCAL
if (hooknum == NF_IP_LOCAL_OUT
&& *var_ipp != orig_dstip
&& !do_extra_mangle(*var_ipp, other_ipp)) {
......@@ -324,6 +325,7 @@ find_best_ips_proto(struct ip_conntrack_tuple *tuple,
* anyway. */
continue;
}
#endif
/* Count how many others map onto this. */
score = count_maps(tuple->src.ip, tuple->dst.ip,
......@@ -367,11 +369,13 @@ find_best_ips_proto_fast(struct ip_conntrack_tuple *tuple,
else {
/* Only do extra mangle when required (breaks
socket binding) */
#ifdef CONFIG_IP_NF_NAT_LOCAL
if (tuple->dst.ip != mr->range[0].min_ip
&& hooknum == NF_IP_LOCAL_OUT
&& !do_extra_mangle(mr->range[0].min_ip,
&tuple->src.ip))
return NULL;
#endif
tuple->dst.ip = mr->range[0].min_ip;
}
}
......@@ -494,7 +498,10 @@ helper_cmp(const struct ip_nat_helper *helper,
static unsigned int opposite_hook[NF_IP_NUMHOOKS]
= { [NF_IP_PRE_ROUTING] = NF_IP_POST_ROUTING,
[NF_IP_POST_ROUTING] = NF_IP_PRE_ROUTING,
[NF_IP_LOCAL_OUT] = NF_IP_POST_ROUTING
#ifdef CONFIG_IP_NF_NAT_LOCAL
[NF_IP_LOCAL_OUT] = NF_IP_LOCAL_IN,
[NF_IP_LOCAL_IN] = NF_IP_LOCAL_OUT,
#endif
};
unsigned int
......
net/ipv4/netfilter/ip_nat_rule.c
View file @ ff5d22a4
......@@ -140,8 +140,12 @@ static unsigned int ipt_dnat_target(struct sk_buff **pskb,
struct ip_conntrack *ct;
enum ip_conntrack_info ctinfo;
#ifdef CONFIG_IP_NF_NAT_LOCAL
IP_NF_ASSERT(hooknum == NF_IP_PRE_ROUTING
|| hooknum == NF_IP_LOCAL_OUT);
#else
IP_NF_ASSERT(hooknum == NF_IP_PRE_ROUTING);
#endif
ct = ip_conntrack_get(*pskb, &ctinfo);
......@@ -210,7 +214,7 @@ static int ipt_dnat_checkentry(const char *tablename,
/* Only allow these for NAT. */
if (strcmp(tablename, "nat") != 0) {
DEBUGP("SNAT: wrong table %s\n", tablename);
DEBUGP("DNAT: wrong table %s\n", tablename);
return 0;
}
......@@ -218,6 +222,14 @@ static int ipt_dnat_checkentry(const char *tablename,
DEBUGP("DNAT: hook mask 0x%x bad\n", hook_mask);
return 0;
}
#ifndef CONFIG_IP_NF_NAT_LOCAL
if (hook_mask & (1 << NF_IP_LOCAL_OUT)) {
DEBUGP("DNAT: CONFIG_IP_NF_NAT_LOCAL not enabled\n");
return 0;
}
#endif
return 1;
}
......
net/ipv4/netfilter/ip_nat_standalone.c
View file @ ff5d22a4
......@@ -42,6 +42,7 @@
#define HOOKNAME(hooknum) ((hooknum) == NF_IP_POST_ROUTING ? "POST_ROUTING" \
: ((hooknum) == NF_IP_PRE_ROUTING ? "PRE_ROUTING" \
: ((hooknum) == NF_IP_LOCAL_OUT ? "LOCAL_OUT" \
: ((hooknum) == NF_IP_LOCAL_IN ? "LOCAL_IN" \
: "*ERROR*")))
static unsigned int
......@@ -95,6 +96,12 @@ ip_nat_fn(unsigned int hooknum,
}
/* Fall thru... (Only ICMPs can be IP_CT_IS_REPLY) */
case IP_CT_NEW:
#ifdef CONFIG_IP_NF_NAT_LOCAL
/* LOCAL_IN hook doesn't have a chain and thus doesn't care
* about new packets -HW */
if (hooknum == NF_IP_LOCAL_IN)
return NF_ACCEPT;
#endif
info = &ct->nat.info;
WRITE_LOCK(&ip_nat_lock);
......@@ -205,6 +212,11 @@ static struct nf_hook_ops ip_nat_out_ops
static struct nf_hook_ops ip_nat_local_out_ops
= { { NULL, NULL }, ip_nat_local_fn, PF_INET, NF_IP_LOCAL_OUT, NF_IP_PRI_NAT_DST };
#ifdef CONFIG_IP_NF_NAT_LOCAL
static struct nf_hook_ops ip_nat_local_in_ops
= { { NULL, NULL }, ip_nat_fn, PF_INET, NF_IP_LOCAL_IN, NF_IP_PRI_NAT_SRC };
#endif
/* Protocol registration. */
int ip_nat_protocol_register(struct ip_nat_protocol *proto)
{
......@@ -273,6 +285,13 @@ static int init_or_cleanup(int init)
printk("ip_nat_init: can't register local out hook.\n");
goto cleanup_outops;
}
#ifdef CONFIG_IP_NF_NAT_LOCAL
ret = nf_register_hook(&ip_nat_local_in_ops);
if (ret < 0) {
printk("ip_nat_init: can't register local in hook.\n");
goto cleanup_localoutops;
}
#endif
if (ip_conntrack_module)
__MOD_INC_USE_COUNT(ip_conntrack_module);
return ret;
......@@ -280,6 +299,10 @@ static int init_or_cleanup(int init)
cleanup:
if (ip_conntrack_module)
__MOD_DEC_USE_COUNT(ip_conntrack_module);
#ifdef CONFIG_IP_NF_NAT_LOCAL
nf_unregister_hook(&ip_nat_local_in_ops);
cleanup_localoutops:
#endif
nf_unregister_hook(&ip_nat_local_out_ops);
cleanup_outops:
nf_unregister_hook(&ip_nat_out_ops);
......
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