1969 lines
48 KiB
C
1969 lines
48 KiB
C
![]() |
/*
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* Packet matching code.
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*
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* Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
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* Copyright (C) 2000-2002 Netfilter core team <coreteam@netfilter.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* 19 Jan 2002 Harald Welte <laforge@gnumonks.org>
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* - increase module usage count as soon as we have rules inside
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* a table
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* 06 Jun 2002 Andras Kis-Szabo <kisza@sch.bme.hu>
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* - new extension header parser code
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*/
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#include <linux/config.h>
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#include <linux/skbuff.h>
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#include <linux/kmod.h>
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#include <linux/vmalloc.h>
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#include <linux/netdevice.h>
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#include <linux/module.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/icmpv6.h>
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#include <net/ip.h>
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#include <net/ipv6.h>
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#include <asm/uaccess.h>
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#include <asm/semaphore.h>
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#include <linux/proc_fs.h>
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#include <linux/netfilter_ipv6/ip6_tables.h>
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
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MODULE_DESCRIPTION("IPv6 packet filter");
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#define IPV6_HDR_LEN (sizeof(struct ipv6hdr))
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#define IPV6_OPTHDR_LEN (sizeof(struct ipv6_opt_hdr))
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/*#define DEBUG_IP_FIREWALL*/
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/*#define DEBUG_ALLOW_ALL*/ /* Useful for remote debugging */
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/*#define DEBUG_IP_FIREWALL_USER*/
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#ifdef DEBUG_IP_FIREWALL
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#define dprintf(format, args...) printk(format , ## args)
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#else
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#define dprintf(format, args...)
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#endif
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#ifdef DEBUG_IP_FIREWALL_USER
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#define duprintf(format, args...) printk(format , ## args)
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#else
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#define duprintf(format, args...)
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#endif
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#ifdef CONFIG_NETFILTER_DEBUG
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#define IP_NF_ASSERT(x) \
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do { \
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if (!(x)) \
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printk("IP_NF_ASSERT: %s:%s:%u\n", \
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__FUNCTION__, __FILE__, __LINE__); \
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} while(0)
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#else
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#define IP_NF_ASSERT(x)
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#endif
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#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
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static DECLARE_MUTEX(ip6t_mutex);
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/* Must have mutex */
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#define ASSERT_READ_LOCK(x) IP_NF_ASSERT(down_trylock(&ip6t_mutex) != 0)
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#define ASSERT_WRITE_LOCK(x) IP_NF_ASSERT(down_trylock(&ip6t_mutex) != 0)
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#include <linux/netfilter_ipv4/listhelp.h>
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#if 0
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/* All the better to debug you with... */
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#define static
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#define inline
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#endif
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/* Locking is simple: we assume at worst case there will be one packet
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in user context and one from bottom halves (or soft irq if Alexey's
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softnet patch was applied).
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We keep a set of rules for each CPU, so we can avoid write-locking
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them; doing a readlock_bh() stops packets coming through if we're
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in user context.
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To be cache friendly on SMP, we arrange them like so:
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[ n-entries ]
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... cache-align padding ...
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[ n-entries ]
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Hence the start of any table is given by get_table() below. */
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/* The table itself */
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struct ip6t_table_info
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{
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/* Size per table */
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unsigned int size;
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/* Number of entries: FIXME. --RR */
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unsigned int number;
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/* Initial number of entries. Needed for module usage count */
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unsigned int initial_entries;
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/* Entry points and underflows */
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unsigned int hook_entry[NF_IP6_NUMHOOKS];
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unsigned int underflow[NF_IP6_NUMHOOKS];
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/* ip6t_entry tables: one per CPU */
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char entries[0] ____cacheline_aligned;
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};
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static LIST_HEAD(ip6t_target);
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static LIST_HEAD(ip6t_match);
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static LIST_HEAD(ip6t_tables);
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#define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0)
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#ifdef CONFIG_SMP
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#define TABLE_OFFSET(t,p) (SMP_ALIGN((t)->size)*(p))
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#else
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#define TABLE_OFFSET(t,p) 0
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#endif
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#if 0
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#define down(x) do { printk("DOWN:%u:" #x "\n", __LINE__); down(x); } while(0)
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#define down_interruptible(x) ({ int __r; printk("DOWNi:%u:" #x "\n", __LINE__); __r = down_interruptible(x); if (__r != 0) printk("ABORT-DOWNi:%u\n", __LINE__); __r; })
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#define up(x) do { printk("UP:%u:" #x "\n", __LINE__); up(x); } while(0)
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#endif
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static int ip6_masked_addrcmp(struct in6_addr addr1, struct in6_addr mask,
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struct in6_addr addr2)
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{
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int i;
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for( i = 0; i < 16; i++){
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if((addr1.s6_addr[i] & mask.s6_addr[i]) !=
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(addr2.s6_addr[i] & mask.s6_addr[i]))
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return 1;
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}
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return 0;
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}
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/* Check for an extension */
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int
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ip6t_ext_hdr(u8 nexthdr)
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{
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return ( (nexthdr == IPPROTO_HOPOPTS) ||
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(nexthdr == IPPROTO_ROUTING) ||
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(nexthdr == IPPROTO_FRAGMENT) ||
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(nexthdr == IPPROTO_ESP) ||
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(nexthdr == IPPROTO_AH) ||
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(nexthdr == IPPROTO_NONE) ||
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(nexthdr == IPPROTO_DSTOPTS) );
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}
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/* Returns whether matches rule or not. */
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static inline int
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ip6_packet_match(const struct sk_buff *skb,
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const char *indev,
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const char *outdev,
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const struct ip6t_ip6 *ip6info,
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unsigned int *protoff,
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int *fragoff)
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{
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size_t i;
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unsigned long ret;
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const struct ipv6hdr *ipv6 = skb->nh.ipv6h;
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#define FWINV(bool,invflg) ((bool) ^ !!(ip6info->invflags & invflg))
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if (FWINV(ip6_masked_addrcmp(ipv6->saddr,ip6info->smsk,ip6info->src),
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IP6T_INV_SRCIP)
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|| FWINV(ip6_masked_addrcmp(ipv6->daddr,ip6info->dmsk,ip6info->dst),
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IP6T_INV_DSTIP)) {
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dprintf("Source or dest mismatch.\n");
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/*
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dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr,
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ipinfo->smsk.s_addr, ipinfo->src.s_addr,
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ipinfo->invflags & IP6T_INV_SRCIP ? " (INV)" : "");
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dprintf("DST: %u. Mask: %u. Target: %u.%s\n", ip->daddr,
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ipinfo->dmsk.s_addr, ipinfo->dst.s_addr,
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ipinfo->invflags & IP6T_INV_DSTIP ? " (INV)" : "");*/
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return 0;
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}
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/* Look for ifname matches; this should unroll nicely. */
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for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
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ret |= (((const unsigned long *)indev)[i]
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^ ((const unsigned long *)ip6info->iniface)[i])
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& ((const unsigned long *)ip6info->iniface_mask)[i];
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}
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if (FWINV(ret != 0, IP6T_INV_VIA_IN)) {
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dprintf("VIA in mismatch (%s vs %s).%s\n",
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indev, ip6info->iniface,
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ip6info->invflags&IP6T_INV_VIA_IN ?" (INV)":"");
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return 0;
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}
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for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
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ret |= (((const unsigned long *)outdev)[i]
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^ ((const unsigned long *)ip6info->outiface)[i])
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& ((const unsigned long *)ip6info->outiface_mask)[i];
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}
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if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) {
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dprintf("VIA out mismatch (%s vs %s).%s\n",
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outdev, ip6info->outiface,
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ip6info->invflags&IP6T_INV_VIA_OUT ?" (INV)":"");
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return 0;
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}
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/* ... might want to do something with class and flowlabel here ... */
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/* look for the desired protocol header */
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if((ip6info->flags & IP6T_F_PROTO)) {
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u_int8_t currenthdr = ipv6->nexthdr;
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struct ipv6_opt_hdr _hdr, *hp;
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u_int16_t ptr; /* Header offset in skb */
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u_int16_t hdrlen; /* Header */
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u_int16_t _fragoff = 0, *fp = NULL;
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ptr = IPV6_HDR_LEN;
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while (ip6t_ext_hdr(currenthdr)) {
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/* Is there enough space for the next ext header? */
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if (skb->len - ptr < IPV6_OPTHDR_LEN)
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return 0;
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/* NONE or ESP: there isn't protocol part */
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/* If we want to count these packets in '-p all',
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* we will change the return 0 to 1*/
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if ((currenthdr == IPPROTO_NONE) ||
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(currenthdr == IPPROTO_ESP))
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break;
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hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
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BUG_ON(hp == NULL);
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/* Size calculation */
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if (currenthdr == IPPROTO_FRAGMENT) {
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fp = skb_header_pointer(skb,
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ptr+offsetof(struct frag_hdr,
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frag_off),
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sizeof(_fragoff),
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&_fragoff);
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if (fp == NULL)
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return 0;
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_fragoff = ntohs(*fp) & ~0x7;
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hdrlen = 8;
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} else if (currenthdr == IPPROTO_AH)
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hdrlen = (hp->hdrlen+2)<<2;
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else
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hdrlen = ipv6_optlen(hp);
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currenthdr = hp->nexthdr;
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ptr += hdrlen;
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/* ptr is too large */
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if ( ptr > skb->len )
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return 0;
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if (_fragoff) {
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if (ip6t_ext_hdr(currenthdr))
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return 0;
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break;
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}
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}
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*protoff = ptr;
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*fragoff = _fragoff;
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/* currenthdr contains the protocol header */
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dprintf("Packet protocol %hi ?= %s%hi.\n",
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currenthdr,
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ip6info->invflags & IP6T_INV_PROTO ? "!":"",
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ip6info->proto);
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if (ip6info->proto == currenthdr) {
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if(ip6info->invflags & IP6T_INV_PROTO) {
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return 0;
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}
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return 1;
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}
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/* We need match for the '-p all', too! */
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if ((ip6info->proto != 0) &&
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!(ip6info->invflags & IP6T_INV_PROTO))
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return 0;
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}
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return 1;
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}
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/* should be ip6 safe */
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static inline int
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ip6_checkentry(const struct ip6t_ip6 *ipv6)
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{
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if (ipv6->flags & ~IP6T_F_MASK) {
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duprintf("Unknown flag bits set: %08X\n",
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ipv6->flags & ~IP6T_F_MASK);
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return 0;
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}
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if (ipv6->invflags & ~IP6T_INV_MASK) {
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duprintf("Unknown invflag bits set: %08X\n",
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ipv6->invflags & ~IP6T_INV_MASK);
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return 0;
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}
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return 1;
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}
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static unsigned int
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ip6t_error(struct sk_buff **pskb,
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const struct net_device *in,
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const struct net_device *out,
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unsigned int hooknum,
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const void *targinfo,
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void *userinfo)
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{
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if (net_ratelimit())
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printk("ip6_tables: error: `%s'\n", (char *)targinfo);
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return NF_DROP;
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}
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static inline
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int do_match(struct ip6t_entry_match *m,
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const struct sk_buff *skb,
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const struct net_device *in,
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const struct net_device *out,
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int offset,
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unsigned int protoff,
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int *hotdrop)
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{
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/* Stop iteration if it doesn't match */
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if (!m->u.kernel.match->match(skb, in, out, m->data,
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offset, protoff, hotdrop))
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return 1;
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else
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return 0;
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}
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static inline struct ip6t_entry *
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get_entry(void *base, unsigned int offset)
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{
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return (struct ip6t_entry *)(base + offset);
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}
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/* Returns one of the generic firewall policies, like NF_ACCEPT. */
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unsigned int
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ip6t_do_table(struct sk_buff **pskb,
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unsigned int hook,
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const struct net_device *in,
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const struct net_device *out,
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struct ip6t_table *table,
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void *userdata)
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{
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static const char nulldevname[IFNAMSIZ];
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int offset = 0;
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unsigned int protoff = 0;
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int hotdrop = 0;
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/* Initializing verdict to NF_DROP keeps gcc happy. */
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unsigned int verdict = NF_DROP;
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const char *indev, *outdev;
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void *table_base;
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struct ip6t_entry *e, *back;
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/* Initialization */
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indev = in ? in->name : nulldevname;
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outdev = out ? out->name : nulldevname;
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/* We handle fragments by dealing with the first fragment as
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* if it was a normal packet. All other fragments are treated
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* normally, except that they will NEVER match rules that ask
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* things we don't know, ie. tcp syn flag or ports). If the
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* rule is also a fragment-specific rule, non-fragments won't
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* match it. */
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read_lock_bh(&table->lock);
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IP_NF_ASSERT(table->valid_hooks & (1 << hook));
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table_base = (void *)table->private->entries
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+ TABLE_OFFSET(table->private, smp_processor_id());
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e = get_entry(table_base, table->private->hook_entry[hook]);
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#ifdef CONFIG_NETFILTER_DEBUG
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/* Check noone else using our table */
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if (((struct ip6t_entry *)table_base)->comefrom != 0xdead57ac
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&& ((struct ip6t_entry *)table_base)->comefrom != 0xeeeeeeec) {
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printk("ASSERT: CPU #%u, %s comefrom(%p) = %X\n",
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smp_processor_id(),
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table->name,
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&((struct ip6t_entry *)table_base)->comefrom,
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((struct ip6t_entry *)table_base)->comefrom);
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}
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((struct ip6t_entry *)table_base)->comefrom = 0x57acc001;
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#endif
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/* For return from builtin chain */
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back = get_entry(table_base, table->private->underflow[hook]);
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do {
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IP_NF_ASSERT(e);
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IP_NF_ASSERT(back);
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if (ip6_packet_match(*pskb, indev, outdev, &e->ipv6,
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&protoff, &offset)) {
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struct ip6t_entry_target *t;
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if (IP6T_MATCH_ITERATE(e, do_match,
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*pskb, in, out,
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offset, protoff, &hotdrop) != 0)
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||
|
goto no_match;
|
||
|
|
||
|
ADD_COUNTER(e->counters,
|
||
|
ntohs((*pskb)->nh.ipv6h->payload_len)
|
||
|
+ IPV6_HDR_LEN,
|
||
|
1);
|
||
|
|
||
|
t = ip6t_get_target(e);
|
||
|
IP_NF_ASSERT(t->u.kernel.target);
|
||
|
/* Standard target? */
|
||
|
if (!t->u.kernel.target->target) {
|
||
|
int v;
|
||
|
|
||
|
v = ((struct ip6t_standard_target *)t)->verdict;
|
||
|
if (v < 0) {
|
||
|
/* Pop from stack? */
|
||
|
if (v != IP6T_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 ip6t_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 */
|
||
|
#ifdef CONFIG_NETFILTER_DEBUG
|
||
|
((struct ip6t_entry *)table_base)->comefrom
|
||
|
= 0xeeeeeeec;
|
||
|
#endif
|
||
|
verdict = t->u.kernel.target->target(pskb,
|
||
|
in, out,
|
||
|
hook,
|
||
|
t->data,
|
||
|
userdata);
|
||
|
|
||
|
#ifdef CONFIG_NETFILTER_DEBUG
|
||
|
if (((struct ip6t_entry *)table_base)->comefrom
|
||
|
!= 0xeeeeeeec
|
||
|
&& verdict == IP6T_CONTINUE) {
|
||
|
printk("Target %s reentered!\n",
|
||
|
t->u.kernel.target->name);
|
||
|
verdict = NF_DROP;
|
||
|
}
|
||
|
((struct ip6t_entry *)table_base)->comefrom
|
||
|
= 0x57acc001;
|
||
|
#endif
|
||
|
if (verdict == IP6T_CONTINUE)
|
||
|
e = (void *)e + e->next_offset;
|
||
|
else
|
||
|
/* Verdict */
|
||
|
break;
|
||
|
}
|
||
|
} else {
|
||
|
|
||
|
no_match:
|
||
|
e = (void *)e + e->next_offset;
|
||
|
}
|
||
|
} while (!hotdrop);
|
||
|
|
||
|
#ifdef CONFIG_NETFILTER_DEBUG
|
||
|
((struct ip6t_entry *)table_base)->comefrom = 0xdead57ac;
|
||
|
#endif
|
||
|
read_unlock_bh(&table->lock);
|
||
|
|
||
|
#ifdef DEBUG_ALLOW_ALL
|
||
|
return NF_ACCEPT;
|
||
|
#else
|
||
|
if (hotdrop)
|
||
|
return NF_DROP;
|
||
|
else return verdict;
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
/* If it succeeds, returns element and locks mutex */
|
||
|
static inline void *
|
||
|
find_inlist_lock_noload(struct list_head *head,
|
||
|
const char *name,
|
||
|
int *error,
|
||
|
struct semaphore *mutex)
|
||
|
{
|
||
|
void *ret;
|
||
|
|
||
|
#if 1
|
||
|
duprintf("find_inlist: searching for `%s' in %s.\n",
|
||
|
name, head == &ip6t_target ? "ip6t_target"
|
||
|
: head == &ip6t_match ? "ip6t_match"
|
||
|
: head == &ip6t_tables ? "ip6t_tables" : "UNKNOWN");
|
||
|
#endif
|
||
|
|
||
|
*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) {
|
||
|
duprintf("find_inlist: loading `%s%s'.\n", prefix, name);
|
||
|
request_module("%s%s", prefix, name);
|
||
|
ret = find_inlist_lock_noload(head, name, error, mutex);
|
||
|
}
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
static inline struct ip6t_table *
|
||
|
ip6t_find_table_lock(const char *name, int *error, struct semaphore *mutex)
|
||
|
{
|
||
|
return find_inlist_lock(&ip6t_tables, name, "ip6table_", error, mutex);
|
||
|
}
|
||
|
|
||
|
static inline struct ip6t_match *
|
||
|
find_match_lock(const char *name, int *error, struct semaphore *mutex)
|
||
|
{
|
||
|
return find_inlist_lock(&ip6t_match, name, "ip6t_", error, mutex);
|
||
|
}
|
||
|
|
||
|
static struct ip6t_target *
|
||
|
ip6t_find_target_lock(const char *name, int *error, struct semaphore *mutex)
|
||
|
{
|
||
|
return find_inlist_lock(&ip6t_target, name, "ip6t_", error, mutex);
|
||
|
}
|
||
|
|
||
|
/* All zeroes == unconditional rule. */
|
||
|
static inline int
|
||
|
unconditional(const struct ip6t_ip6 *ipv6)
|
||
|
{
|
||
|
unsigned int i;
|
||
|
|
||
|
for (i = 0; i < sizeof(*ipv6); i++)
|
||
|
if (((char *)ipv6)[i])
|
||
|
break;
|
||
|
|
||
|
return (i == sizeof(*ipv6));
|
||
|
}
|
||
|
|
||
|
/* 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 ip6t_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_IP6_NUMHOOKS; hook++) {
|
||
|
unsigned int pos = newinfo->hook_entry[hook];
|
||
|
struct ip6t_entry *e
|
||
|
= (struct ip6t_entry *)(newinfo->entries + pos);
|
||
|
|
||
|
if (!(valid_hooks & (1 << hook)))
|
||
|
continue;
|
||
|
|
||
|
/* Set initial back pointer. */
|
||
|
e->counters.pcnt = pos;
|
||
|
|
||
|
for (;;) {
|
||
|
struct ip6t_standard_target *t
|
||
|
= (void *)ip6t_get_target(e);
|
||
|
|
||
|
if (e->comefrom & (1 << NF_IP6_NUMHOOKS)) {
|
||
|
printk("iptables: loop hook %u pos %u %08X.\n",
|
||
|
hook, pos, e->comefrom);
|
||
|
return 0;
|
||
|
}
|
||
|
e->comefrom
|
||
|
|= ((1 << hook) | (1 << NF_IP6_NUMHOOKS));
|
||
|
|
||
|
/* Unconditional return/END. */
|
||
|
if (e->target_offset == sizeof(struct ip6t_entry)
|
||
|
&& (strcmp(t->target.u.user.name,
|
||
|
IP6T_STANDARD_TARGET) == 0)
|
||
|
&& t->verdict < 0
|
||
|
&& unconditional(&e->ipv6)) {
|
||
|
unsigned int oldpos, size;
|
||
|
|
||
|
/* Return: backtrack through the last
|
||
|
big jump. */
|
||
|
do {
|
||
|
e->comefrom ^= (1<<NF_IP6_NUMHOOKS);
|
||
|
#ifdef DEBUG_IP_FIREWALL_USER
|
||
|
if (e->comefrom
|
||
|
& (1 << NF_IP6_NUMHOOKS)) {
|
||
|
duprintf("Back unset "
|
||
|
"on hook %u "
|
||
|
"rule %u\n",
|
||
|
hook, pos);
|
||
|
}
|
||
|
#endif
|
||
|
oldpos = pos;
|
||
|
pos = e->counters.pcnt;
|
||
|
e->counters.pcnt = 0;
|
||
|
|
||
|
/* We're at the start. */
|
||
|
if (pos == oldpos)
|
||
|
goto next;
|
||
|
|
||
|
e = (struct ip6t_entry *)
|
||
|
(newinfo->entries + pos);
|
||
|
} while (oldpos == pos + e->next_offset);
|
||
|
|
||
|
/* Move along one */
|
||
|
size = e->next_offset;
|
||
|
e = (struct ip6t_entry *)
|
||
|
(newinfo->entries + pos + size);
|
||
|
e->counters.pcnt = pos;
|
||
|
pos += size;
|
||
|
} else {
|
||
|
int newpos = t->verdict;
|
||
|
|
||
|
if (strcmp(t->target.u.user.name,
|
||
|
IP6T_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 ip6t_entry *)
|
||
|
(newinfo->entries + newpos);
|
||
|
e->counters.pcnt = pos;
|
||
|
pos = newpos;
|
||
|
}
|
||
|
}
|
||
|
next:
|
||
|
duprintf("Finished chain %u\n", hook);
|
||
|
}
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
static inline int
|
||
|
cleanup_match(struct ip6t_entry_match *m, unsigned int *i)
|
||
|
{
|
||
|
if (i && (*i)-- == 0)
|
||
|
return 1;
|
||
|
|
||
|
if (m->u.kernel.match->destroy)
|
||
|
m->u.kernel.match->destroy(m->data,
|
||
|
m->u.match_size - sizeof(*m));
|
||
|
module_put(m->u.kernel.match->me);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static inline int
|
||
|
standard_check(const struct ip6t_entry_target *t,
|
||
|
unsigned int max_offset)
|
||
|
{
|
||
|
struct ip6t_standard_target *targ = (void *)t;
|
||
|
|
||
|
/* Check standard info. */
|
||
|
if (t->u.target_size
|
||
|
!= IP6T_ALIGN(sizeof(struct ip6t_standard_target))) {
|
||
|
duprintf("standard_check: target size %u != %u\n",
|
||
|
t->u.target_size,
|
||
|
IP6T_ALIGN(sizeof(struct ip6t_standard_target)));
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
if (targ->verdict >= 0
|
||
|
&& targ->verdict > max_offset - sizeof(struct ip6t_entry)) {
|
||
|
duprintf("ip6t_standard_check: bad verdict (%i)\n",
|
||
|
targ->verdict);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
if (targ->verdict < -NF_MAX_VERDICT - 1) {
|
||
|
duprintf("ip6t_standard_check: bad negative verdict (%i)\n",
|
||
|
targ->verdict);
|
||
|
return 0;
|
||
|
}
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
static inline int
|
||
|
check_match(struct ip6t_entry_match *m,
|
||
|
const char *name,
|
||
|
const struct ip6t_ip6 *ipv6,
|
||
|
unsigned int hookmask,
|
||
|
unsigned int *i)
|
||
|
{
|
||
|
int ret;
|
||
|
struct ip6t_match *match;
|
||
|
|
||
|
match = find_match_lock(m->u.user.name, &ret, &ip6t_mutex);
|
||
|
if (!match) {
|
||
|
// duprintf("check_match: `%s' not found\n", m->u.name);
|
||
|
return ret;
|
||
|
}
|
||
|
if (!try_module_get(match->me)) {
|
||
|
up(&ip6t_mutex);
|
||
|
return -ENOENT;
|
||
|
}
|
||
|
m->u.kernel.match = match;
|
||
|
up(&ip6t_mutex);
|
||
|
|
||
|
if (m->u.kernel.match->checkentry
|
||
|
&& !m->u.kernel.match->checkentry(name, ipv6, m->data,
|
||
|
m->u.match_size - sizeof(*m),
|
||
|
hookmask)) {
|
||
|
module_put(m->u.kernel.match->me);
|
||
|
duprintf("ip_tables: check failed for `%s'.\n",
|
||
|
m->u.kernel.match->name);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
(*i)++;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static struct ip6t_target ip6t_standard_target;
|
||
|
|
||
|
static inline int
|
||
|
check_entry(struct ip6t_entry *e, const char *name, unsigned int size,
|
||
|
unsigned int *i)
|
||
|
{
|
||
|
struct ip6t_entry_target *t;
|
||
|
struct ip6t_target *target;
|
||
|
int ret;
|
||
|
unsigned int j;
|
||
|
|
||
|
if (!ip6_checkentry(&e->ipv6)) {
|
||
|
duprintf("ip_tables: ip check failed %p %s.\n", e, name);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
j = 0;
|
||
|
ret = IP6T_MATCH_ITERATE(e, check_match, name, &e->ipv6, e->comefrom, &j);
|
||
|
if (ret != 0)
|
||
|
goto cleanup_matches;
|
||
|
|
||
|
t = ip6t_get_target(e);
|
||
|
target = ip6t_find_target_lock(t->u.user.name, &ret, &ip6t_mutex);
|
||
|
if (!target) {
|
||
|
duprintf("check_entry: `%s' not found\n", t->u.user.name);
|
||
|
goto cleanup_matches;
|
||
|
}
|
||
|
if (!try_module_get(target->me)) {
|
||
|
up(&ip6t_mutex);
|
||
|
ret = -ENOENT;
|
||
|
goto cleanup_matches;
|
||
|
}
|
||
|
t->u.kernel.target = target;
|
||
|
up(&ip6t_mutex);
|
||
|
if (!t->u.kernel.target) {
|
||
|
ret = -EBUSY;
|
||
|
goto cleanup_matches;
|
||
|
}
|
||
|
if (t->u.kernel.target == &ip6t_standard_target) {
|
||
|
if (!standard_check(t, size)) {
|
||
|
ret = -EINVAL;
|
||
|
goto cleanup_matches;
|
||
|
}
|
||
|
} else if (t->u.kernel.target->checkentry
|
||
|
&& !t->u.kernel.target->checkentry(name, e, t->data,
|
||
|
t->u.target_size
|
||
|
- sizeof(*t),
|
||
|
e->comefrom)) {
|
||
|
module_put(t->u.kernel.target->me);
|
||
|
duprintf("ip_tables: check failed for `%s'.\n",
|
||
|
t->u.kernel.target->name);
|
||
|
ret = -EINVAL;
|
||
|
goto cleanup_matches;
|
||
|
}
|
||
|
|
||
|
(*i)++;
|
||
|
return 0;
|
||
|
|
||
|
cleanup_matches:
|
||
|
IP6T_MATCH_ITERATE(e, cleanup_match, &j);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static inline int
|
||
|
check_entry_size_and_hooks(struct ip6t_entry *e,
|
||
|
struct ip6t_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 ip6t_entry) != 0
|
||
|
|| (unsigned char *)e + sizeof(struct ip6t_entry) >= limit) {
|
||
|
duprintf("Bad offset %p\n", e);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
if (e->next_offset
|
||
|
< sizeof(struct ip6t_entry) + sizeof(struct ip6t_entry_target)) {
|
||
|
duprintf("checking: element %p size %u\n",
|
||
|
e, e->next_offset);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* Check hooks & underflows */
|
||
|
for (h = 0; h < NF_IP6_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 IP6T_RETURN). --RR */
|
||
|
|
||
|
/* Clear counters and comefrom */
|
||
|
e->counters = ((struct ip6t_counters) { 0, 0 });
|
||
|
e->comefrom = 0;
|
||
|
|
||
|
(*i)++;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static inline int
|
||
|
cleanup_entry(struct ip6t_entry *e, unsigned int *i)
|
||
|
{
|
||
|
struct ip6t_entry_target *t;
|
||
|
|
||
|
if (i && (*i)-- == 0)
|
||
|
return 1;
|
||
|
|
||
|
/* Cleanup all matches */
|
||
|
IP6T_MATCH_ITERATE(e, cleanup_match, NULL);
|
||
|
t = ip6t_get_target(e);
|
||
|
if (t->u.kernel.target->destroy)
|
||
|
t->u.kernel.target->destroy(t->data,
|
||
|
t->u.target_size - sizeof(*t));
|
||
|
module_put(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 ip6t_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_IP6_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 = IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size,
|
||
|
check_entry_size_and_hooks,
|
||
|
newinfo,
|
||
|
newinfo->entries,
|
||
|
newinfo->entries + size,
|
||
|
hook_entries, underflows, &i);
|
||
|
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_IP6_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))
|
||
|
return -ELOOP;
|
||
|
|
||
|
/* Finally, each sanity check must pass */
|
||
|
i = 0;
|
||
|
ret = IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size,
|
||
|
check_entry, name, size, &i);
|
||
|
|
||
|
if (ret != 0) {
|
||
|
IP6T_ENTRY_ITERATE(newinfo->entries, newinfo->size,
|
||
|
cleanup_entry, &i);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
/* And one copy for every other CPU */
|
||
|
for (i = 1; i < num_possible_cpus(); i++) {
|
||
|
memcpy(newinfo->entries + SMP_ALIGN(newinfo->size)*i,
|
||
|
newinfo->entries,
|
||
|
SMP_ALIGN(newinfo->size));
|
||
|
}
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static struct ip6t_table_info *
|
||
|
replace_table(struct ip6t_table *table,
|
||
|
unsigned int num_counters,
|
||
|
struct ip6t_table_info *newinfo,
|
||
|
int *error)
|
||
|
{
|
||
|
struct ip6t_table_info *oldinfo;
|
||
|
|
||
|
#ifdef CONFIG_NETFILTER_DEBUG
|
||
|
{
|
||
|
struct ip6t_entry *table_base;
|
||
|
unsigned int i;
|
||
|
|
||
|
for (i = 0; i < num_possible_cpus(); i++) {
|
||
|
table_base =
|
||
|
(void *)newinfo->entries
|
||
|
+ TABLE_OFFSET(newinfo, i);
|
||
|
|
||
|
table_base->comefrom = 0xdead57ac;
|
||
|
}
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
/* 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 ip6t_entry *e,
|
||
|
struct ip6t_counters total[],
|
||
|
unsigned int *i)
|
||
|
{
|
||
|
ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt);
|
||
|
|
||
|
(*i)++;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
get_counters(const struct ip6t_table_info *t,
|
||
|
struct ip6t_counters counters[])
|
||
|
{
|
||
|
unsigned int cpu;
|
||
|
unsigned int i;
|
||
|
|
||
|
for (cpu = 0; cpu < num_possible_cpus(); cpu++) {
|
||
|
i = 0;
|
||
|
IP6T_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 ip6t_table *table,
|
||
|
void __user *userptr)
|
||
|
{
|
||
|
unsigned int off, num, countersize;
|
||
|
struct ip6t_entry *e;
|
||
|
struct ip6t_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 ip6t_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++){
|
||
|
unsigned int i;
|
||
|
struct ip6t_entry_match *m;
|
||
|
struct ip6t_entry_target *t;
|
||
|
|
||
|
e = (struct ip6t_entry *)(table->private->entries + off);
|
||
|
if (copy_to_user(userptr + off
|
||
|
+ offsetof(struct ip6t_entry, counters),
|
||
|
&counters[num],
|
||
|
sizeof(counters[num])) != 0) {
|
||
|
ret = -EFAULT;
|
||
|
goto free_counters;
|
||
|
}
|
||
|
|
||
|
for (i = sizeof(struct ip6t_entry);
|
||
|
i < e->target_offset;
|
||
|
i += m->u.match_size) {
|
||
|
m = (void *)e + i;
|
||
|
|
||
|
if (copy_to_user(userptr + off + i
|
||
|
+ offsetof(struct ip6t_entry_match,
|
||
|
u.user.name),
|
||
|
m->u.kernel.match->name,
|
||
|
strlen(m->u.kernel.match->name)+1)
|
||
|
!= 0) {
|
||
|
ret = -EFAULT;
|
||
|
goto free_counters;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
t = ip6t_get_target(e);
|
||
|
if (copy_to_user(userptr + off + e->target_offset
|
||
|
+ offsetof(struct ip6t_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 ip6t_get_entries *entries,
|
||
|
struct ip6t_get_entries __user *uptr)
|
||
|
{
|
||
|
int ret;
|
||
|
struct ip6t_table *t;
|
||
|
|
||
|
t = ip6t_find_table_lock(entries->name, &ret, &ip6t_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(&ip6t_mutex);
|
||
|
} else
|
||
|
duprintf("get_entries: Can't find %s!\n",
|
||
|
entries->name);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
do_replace(void __user *user, unsigned int len)
|
||
|
{
|
||
|
int ret;
|
||
|
struct ip6t_replace tmp;
|
||
|
struct ip6t_table *t;
|
||
|
struct ip6t_table_info *newinfo, *oldinfo;
|
||
|
struct ip6t_counters *counters;
|
||
|
|
||
|
if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
|
||
|
return -EFAULT;
|
||
|
|
||
|
/* 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 ip6t_table_info)
|
||
|
+ SMP_ALIGN(tmp.size) * num_possible_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 ip6t_counters));
|
||
|
if (!counters) {
|
||
|
ret = -ENOMEM;
|
||
|
goto free_newinfo;
|
||
|
}
|
||
|
memset(counters, 0, tmp.num_counters * sizeof(struct ip6t_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("ip_tables: Translated table\n");
|
||
|
|
||
|
t = ip6t_find_table_lock(tmp.name, &ret, &ip6t_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;
|
||
|
}
|
||
|
|
||
|
/* Get a reference in advance, we're not allowed fail later */
|
||
|
if (!try_module_get(t->me)) {
|
||
|
ret = -EBUSY;
|
||
|
goto free_newinfo_counters_untrans_unlock;
|
||
|
}
|
||
|
|
||
|
oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret);
|
||
|
if (!oldinfo)
|
||
|
goto put_module;
|
||
|
|
||
|
/* 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 ((oldinfo->number > oldinfo->initial_entries) ||
|
||
|
(newinfo->number <= oldinfo->initial_entries))
|
||
|
module_put(t->me);
|
||
|
if ((oldinfo->number > oldinfo->initial_entries) &&
|
||
|
(newinfo->number <= oldinfo->initial_entries))
|
||
|
module_put(t->me);
|
||
|
|
||
|
/* Get the old counters. */
|
||
|
get_counters(oldinfo, counters);
|
||
|
/* Decrease module usage counts and free resource */
|
||
|
IP6T_ENTRY_ITERATE(oldinfo->entries, oldinfo->size, cleanup_entry,NULL);
|
||
|
vfree(oldinfo);
|
||
|
/* Silent error: too late now. */
|
||
|
if (copy_to_user(tmp.counters, counters,
|
||
|
sizeof(struct ip6t_counters) * tmp.num_counters) != 0)
|
||
|
ret = -EFAULT;
|
||
|
vfree(counters);
|
||
|
up(&ip6t_mutex);
|
||
|
return ret;
|
||
|
|
||
|
put_module:
|
||
|
module_put(t->me);
|
||
|
free_newinfo_counters_untrans_unlock:
|
||
|
up(&ip6t_mutex);
|
||
|
free_newinfo_counters_untrans:
|
||
|
IP6T_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 ip6t_entry *e,
|
||
|
const struct ip6t_counters addme[],
|
||
|
unsigned int *i)
|
||
|
{
|
||
|
#if 0
|
||
|
duprintf("add_counter: Entry %u %lu/%lu + %lu/%lu\n",
|
||
|
*i,
|
||
|
(long unsigned int)e->counters.pcnt,
|
||
|
(long unsigned int)e->counters.bcnt,
|
||
|
(long unsigned int)addme[*i].pcnt,
|
||
|
(long unsigned int)addme[*i].bcnt);
|
||
|
#endif
|
||
|
|
||
|
ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt);
|
||
|
|
||
|
(*i)++;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
do_add_counters(void __user *user, unsigned int len)
|
||
|
{
|
||
|
unsigned int i;
|
||
|
struct ip6t_counters_info tmp, *paddc;
|
||
|
struct ip6t_table *t;
|
||
|
int ret;
|
||
|
|
||
|
if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
|
||
|
return -EFAULT;
|
||
|
|
||
|
if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct ip6t_counters))
|
||
|
return -EINVAL;
|
||
|
|
||
|
paddc = vmalloc(len);
|
||
|
if (!paddc)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
if (copy_from_user(paddc, user, len) != 0) {
|
||
|
ret = -EFAULT;
|
||
|
goto free;
|
||
|
}
|
||
|
|
||
|
t = ip6t_find_table_lock(tmp.name, &ret, &ip6t_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;
|
||
|
IP6T_ENTRY_ITERATE(t->private->entries,
|
||
|
t->private->size,
|
||
|
add_counter_to_entry,
|
||
|
paddc->counters,
|
||
|
&i);
|
||
|
unlock_up_free:
|
||
|
write_unlock_bh(&t->lock);
|
||
|
up(&ip6t_mutex);
|
||
|
free:
|
||
|
vfree(paddc);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
|
||
|
{
|
||
|
int ret;
|
||
|
|
||
|
if (!capable(CAP_NET_ADMIN))
|
||
|
return -EPERM;
|
||
|
|
||
|
switch (cmd) {
|
||
|
case IP6T_SO_SET_REPLACE:
|
||
|
ret = do_replace(user, len);
|
||
|
break;
|
||
|
|
||
|
case IP6T_SO_SET_ADD_COUNTERS:
|
||
|
ret = do_add_counters(user, len);
|
||
|
break;
|
||
|
|
||
|
default:
|
||
|
duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd);
|
||
|
ret = -EINVAL;
|
||
|
}
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
|
||
|
{
|
||
|
int ret;
|
||
|
|
||
|
if (!capable(CAP_NET_ADMIN))
|
||
|
return -EPERM;
|
||
|
|
||
|
switch (cmd) {
|
||
|
case IP6T_SO_GET_INFO: {
|
||
|
char name[IP6T_TABLE_MAXNAMELEN];
|
||
|
struct ip6t_table *t;
|
||
|
|
||
|
if (*len != sizeof(struct ip6t_getinfo)) {
|
||
|
duprintf("length %u != %u\n", *len,
|
||
|
sizeof(struct ip6t_getinfo));
|
||
|
ret = -EINVAL;
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
if (copy_from_user(name, user, sizeof(name)) != 0) {
|
||
|
ret = -EFAULT;
|
||
|
break;
|
||
|
}
|
||
|
name[IP6T_TABLE_MAXNAMELEN-1] = '\0';
|
||
|
t = ip6t_find_table_lock(name, &ret, &ip6t_mutex);
|
||
|
if (t) {
|
||
|
struct ip6t_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;
|
||
|
memcpy(info.name, name, sizeof(info.name));
|
||
|
|
||
|
if (copy_to_user(user, &info, *len) != 0)
|
||
|
ret = -EFAULT;
|
||
|
else
|
||
|
ret = 0;
|
||
|
|
||
|
up(&ip6t_mutex);
|
||
|
}
|
||
|
}
|
||
|
break;
|
||
|
|
||
|
case IP6T_SO_GET_ENTRIES: {
|
||
|
struct ip6t_get_entries get;
|
||
|
|
||
|
if (*len < sizeof(get)) {
|
||
|
duprintf("get_entries: %u < %u\n", *len, sizeof(get));
|
||
|
ret = -EINVAL;
|
||
|
} else if (copy_from_user(&get, user, sizeof(get)) != 0) {
|
||
|
ret = -EFAULT;
|
||
|
} else if (*len != sizeof(struct ip6t_get_entries) + get.size) {
|
||
|
duprintf("get_entries: %u != %u\n", *len,
|
||
|
sizeof(struct ip6t_get_entries) + get.size);
|
||
|
ret = -EINVAL;
|
||
|
} else
|
||
|
ret = get_entries(&get, user);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
default:
|
||
|
duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd);
|
||
|
ret = -EINVAL;
|
||
|
}
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
/* Registration hooks for targets. */
|
||
|
int
|
||
|
ip6t_register_target(struct ip6t_target *target)
|
||
|
{
|
||
|
int ret;
|
||
|
|
||
|
ret = down_interruptible(&ip6t_mutex);
|
||
|
if (ret != 0)
|
||
|
return ret;
|
||
|
|
||
|
if (!list_named_insert(&ip6t_target, target)) {
|
||
|
duprintf("ip6t_register_target: `%s' already in list!\n",
|
||
|
target->name);
|
||
|
ret = -EINVAL;
|
||
|
}
|
||
|
up(&ip6t_mutex);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
void
|
||
|
ip6t_unregister_target(struct ip6t_target *target)
|
||
|
{
|
||
|
down(&ip6t_mutex);
|
||
|
LIST_DELETE(&ip6t_target, target);
|
||
|
up(&ip6t_mutex);
|
||
|
}
|
||
|
|
||
|
int
|
||
|
ip6t_register_match(struct ip6t_match *match)
|
||
|
{
|
||
|
int ret;
|
||
|
|
||
|
ret = down_interruptible(&ip6t_mutex);
|
||
|
if (ret != 0)
|
||
|
return ret;
|
||
|
|
||
|
if (!list_named_insert(&ip6t_match, match)) {
|
||
|
duprintf("ip6t_register_match: `%s' already in list!\n",
|
||
|
match->name);
|
||
|
ret = -EINVAL;
|
||
|
}
|
||
|
up(&ip6t_mutex);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
void
|
||
|
ip6t_unregister_match(struct ip6t_match *match)
|
||
|
{
|
||
|
down(&ip6t_mutex);
|
||
|
LIST_DELETE(&ip6t_match, match);
|
||
|
up(&ip6t_mutex);
|
||
|
}
|
||
|
|
||
|
int ip6t_register_table(struct ip6t_table *table,
|
||
|
const struct ip6t_replace *repl)
|
||
|
{
|
||
|
int ret;
|
||
|
struct ip6t_table_info *newinfo;
|
||
|
static struct ip6t_table_info bootstrap
|
||
|
= { 0, 0, 0, { 0 }, { 0 }, { } };
|
||
|
|
||
|
newinfo = vmalloc(sizeof(struct ip6t_table_info)
|
||
|
+ SMP_ALIGN(repl->size) * num_possible_cpus());
|
||
|
if (!newinfo)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
memcpy(newinfo->entries, repl->entries, repl->size);
|
||
|
|
||
|
ret = translate_table(table->name, table->valid_hooks,
|
||
|
newinfo, repl->size,
|
||
|
repl->num_entries,
|
||
|
repl->hook_entry,
|
||
|
repl->underflow);
|
||
|
if (ret != 0) {
|
||
|
vfree(newinfo);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
ret = down_interruptible(&ip6t_mutex);
|
||
|
if (ret != 0) {
|
||
|
vfree(newinfo);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
/* Don't autoload: we'd eat our tail... */
|
||
|
if (list_named_find(&ip6t_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;
|
||
|
|
||
|
rwlock_init(&table->lock);
|
||
|
list_prepend(&ip6t_tables, table);
|
||
|
|
||
|
unlock:
|
||
|
up(&ip6t_mutex);
|
||
|
return ret;
|
||
|
|
||
|
free_unlock:
|
||
|
vfree(newinfo);
|
||
|
goto unlock;
|
||
|
}
|
||
|
|
||
|
void ip6t_unregister_table(struct ip6t_table *table)
|
||
|
{
|
||
|
down(&ip6t_mutex);
|
||
|
LIST_DELETE(&ip6t_tables, table);
|
||
|
up(&ip6t_mutex);
|
||
|
|
||
|
/* Decrease module usage counts and free resources */
|
||
|
IP6T_ENTRY_ITERATE(table->private->entries, table->private->size,
|
||
|
cleanup_entry, NULL);
|
||
|
vfree(table->private);
|
||
|
}
|
||
|
|
||
|
/* Returns 1 if the port is matched by the range, 0 otherwise */
|
||
|
static inline int
|
||
|
port_match(u_int16_t min, u_int16_t max, u_int16_t port, int invert)
|
||
|
{
|
||
|
int ret;
|
||
|
|
||
|
ret = (port >= min && port <= max) ^ invert;
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
tcp_find_option(u_int8_t option,
|
||
|
const struct sk_buff *skb,
|
||
|
unsigned int tcpoff,
|
||
|
unsigned int optlen,
|
||
|
int invert,
|
||
|
int *hotdrop)
|
||
|
{
|
||
|
/* tcp.doff is only 4 bits, ie. max 15 * 4 bytes */
|
||
|
u_int8_t _opt[60 - sizeof(struct tcphdr)], *op;
|
||
|
unsigned int i;
|
||
|
|
||
|
duprintf("tcp_match: finding option\n");
|
||
|
if (!optlen)
|
||
|
return invert;
|
||
|
/* If we don't have the whole header, drop packet. */
|
||
|
op = skb_header_pointer(skb, tcpoff + sizeof(struct tcphdr), optlen,
|
||
|
_opt);
|
||
|
if (op == NULL) {
|
||
|
*hotdrop = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
for (i = 0; i < optlen; ) {
|
||
|
if (op[i] == option) return !invert;
|
||
|
if (op[i] < 2) i++;
|
||
|
else i += op[i+1]?:1;
|
||
|
}
|
||
|
|
||
|
return invert;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
tcp_match(const struct sk_buff *skb,
|
||
|
const struct net_device *in,
|
||
|
const struct net_device *out,
|
||
|
const void *matchinfo,
|
||
|
int offset,
|
||
|
unsigned int protoff,
|
||
|
int *hotdrop)
|
||
|
{
|
||
|
struct tcphdr _tcph, *th;
|
||
|
const struct ip6t_tcp *tcpinfo = matchinfo;
|
||
|
|
||
|
if (offset) {
|
||
|
/* To quote Alan:
|
||
|
|
||
|
Don't allow a fragment of TCP 8 bytes in. Nobody normal
|
||
|
causes this. Its a cracker trying to break in by doing a
|
||
|
flag overwrite to pass the direction checks.
|
||
|
*/
|
||
|
if (offset == 1) {
|
||
|
duprintf("Dropping evil TCP offset=1 frag.\n");
|
||
|
*hotdrop = 1;
|
||
|
}
|
||
|
/* Must not be a fragment. */
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
#define FWINVTCP(bool,invflg) ((bool) ^ !!(tcpinfo->invflags & invflg))
|
||
|
|
||
|
th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
|
||
|
if (th == NULL) {
|
||
|
/* We've been asked to examine this packet, and we
|
||
|
can't. Hence, no choice but to drop. */
|
||
|
duprintf("Dropping evil TCP offset=0 tinygram.\n");
|
||
|
*hotdrop = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
if (!port_match(tcpinfo->spts[0], tcpinfo->spts[1],
|
||
|
ntohs(th->source),
|
||
|
!!(tcpinfo->invflags & IP6T_TCP_INV_SRCPT)))
|
||
|
return 0;
|
||
|
if (!port_match(tcpinfo->dpts[0], tcpinfo->dpts[1],
|
||
|
ntohs(th->dest),
|
||
|
!!(tcpinfo->invflags & IP6T_TCP_INV_DSTPT)))
|
||
|
return 0;
|
||
|
if (!FWINVTCP((((unsigned char *)th)[13] & tcpinfo->flg_mask)
|
||
|
== tcpinfo->flg_cmp,
|
||
|
IP6T_TCP_INV_FLAGS))
|
||
|
return 0;
|
||
|
if (tcpinfo->option) {
|
||
|
if (th->doff * 4 < sizeof(_tcph)) {
|
||
|
*hotdrop = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
if (!tcp_find_option(tcpinfo->option, skb, protoff,
|
||
|
th->doff*4 - sizeof(*th),
|
||
|
tcpinfo->invflags & IP6T_TCP_INV_OPTION,
|
||
|
hotdrop))
|
||
|
return 0;
|
||
|
}
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
/* Called when user tries to insert an entry of this type. */
|
||
|
static int
|
||
|
tcp_checkentry(const char *tablename,
|
||
|
const struct ip6t_ip6 *ipv6,
|
||
|
void *matchinfo,
|
||
|
unsigned int matchsize,
|
||
|
unsigned int hook_mask)
|
||
|
{
|
||
|
const struct ip6t_tcp *tcpinfo = matchinfo;
|
||
|
|
||
|
/* Must specify proto == TCP, and no unknown invflags */
|
||
|
return ipv6->proto == IPPROTO_TCP
|
||
|
&& !(ipv6->invflags & IP6T_INV_PROTO)
|
||
|
&& matchsize == IP6T_ALIGN(sizeof(struct ip6t_tcp))
|
||
|
&& !(tcpinfo->invflags & ~IP6T_TCP_INV_MASK);
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
udp_match(const struct sk_buff *skb,
|
||
|
const struct net_device *in,
|
||
|
const struct net_device *out,
|
||
|
const void *matchinfo,
|
||
|
int offset,
|
||
|
unsigned int protoff,
|
||
|
int *hotdrop)
|
||
|
{
|
||
|
struct udphdr _udph, *uh;
|
||
|
const struct ip6t_udp *udpinfo = matchinfo;
|
||
|
|
||
|
/* Must not be a fragment. */
|
||
|
if (offset)
|
||
|
return 0;
|
||
|
|
||
|
uh = skb_header_pointer(skb, protoff, sizeof(_udph), &_udph);
|
||
|
if (uh == NULL) {
|
||
|
/* We've been asked to examine this packet, and we
|
||
|
can't. Hence, no choice but to drop. */
|
||
|
duprintf("Dropping evil UDP tinygram.\n");
|
||
|
*hotdrop = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
return port_match(udpinfo->spts[0], udpinfo->spts[1],
|
||
|
ntohs(uh->source),
|
||
|
!!(udpinfo->invflags & IP6T_UDP_INV_SRCPT))
|
||
|
&& port_match(udpinfo->dpts[0], udpinfo->dpts[1],
|
||
|
ntohs(uh->dest),
|
||
|
!!(udpinfo->invflags & IP6T_UDP_INV_DSTPT));
|
||
|
}
|
||
|
|
||
|
/* Called when user tries to insert an entry of this type. */
|
||
|
static int
|
||
|
udp_checkentry(const char *tablename,
|
||
|
const struct ip6t_ip6 *ipv6,
|
||
|
void *matchinfo,
|
||
|
unsigned int matchinfosize,
|
||
|
unsigned int hook_mask)
|
||
|
{
|
||
|
const struct ip6t_udp *udpinfo = matchinfo;
|
||
|
|
||
|
/* Must specify proto == UDP, and no unknown invflags */
|
||
|
if (ipv6->proto != IPPROTO_UDP || (ipv6->invflags & IP6T_INV_PROTO)) {
|
||
|
duprintf("ip6t_udp: Protocol %u != %u\n", ipv6->proto,
|
||
|
IPPROTO_UDP);
|
||
|
return 0;
|
||
|
}
|
||
|
if (matchinfosize != IP6T_ALIGN(sizeof(struct ip6t_udp))) {
|
||
|
duprintf("ip6t_udp: matchsize %u != %u\n",
|
||
|
matchinfosize, IP6T_ALIGN(sizeof(struct ip6t_udp)));
|
||
|
return 0;
|
||
|
}
|
||
|
if (udpinfo->invflags & ~IP6T_UDP_INV_MASK) {
|
||
|
duprintf("ip6t_udp: unknown flags %X\n",
|
||
|
udpinfo->invflags);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
/* Returns 1 if the type and code is matched by the range, 0 otherwise */
|
||
|
static inline int
|
||
|
icmp6_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code,
|
||
|
u_int8_t type, u_int8_t code,
|
||
|
int invert)
|
||
|
{
|
||
|
return (type == test_type && code >= min_code && code <= max_code)
|
||
|
^ invert;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
icmp6_match(const struct sk_buff *skb,
|
||
|
const struct net_device *in,
|
||
|
const struct net_device *out,
|
||
|
const void *matchinfo,
|
||
|
int offset,
|
||
|
unsigned int protoff,
|
||
|
int *hotdrop)
|
||
|
{
|
||
|
struct icmp6hdr _icmp, *ic;
|
||
|
const struct ip6t_icmp *icmpinfo = matchinfo;
|
||
|
|
||
|
/* Must not be a fragment. */
|
||
|
if (offset)
|
||
|
return 0;
|
||
|
|
||
|
ic = skb_header_pointer(skb, protoff, sizeof(_icmp), &_icmp);
|
||
|
if (ic == NULL) {
|
||
|
/* We've been asked to examine this packet, and we
|
||
|
can't. Hence, no choice but to drop. */
|
||
|
duprintf("Dropping evil ICMP tinygram.\n");
|
||
|
*hotdrop = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
return icmp6_type_code_match(icmpinfo->type,
|
||
|
icmpinfo->code[0],
|
||
|
icmpinfo->code[1],
|
||
|
ic->icmp6_type, ic->icmp6_code,
|
||
|
!!(icmpinfo->invflags&IP6T_ICMP_INV));
|
||
|
}
|
||
|
|
||
|
/* Called when user tries to insert an entry of this type. */
|
||
|
static int
|
||
|
icmp6_checkentry(const char *tablename,
|
||
|
const struct ip6t_ip6 *ipv6,
|
||
|
void *matchinfo,
|
||
|
unsigned int matchsize,
|
||
|
unsigned int hook_mask)
|
||
|
{
|
||
|
const struct ip6t_icmp *icmpinfo = matchinfo;
|
||
|
|
||
|
/* Must specify proto == ICMP, and no unknown invflags */
|
||
|
return ipv6->proto == IPPROTO_ICMPV6
|
||
|
&& !(ipv6->invflags & IP6T_INV_PROTO)
|
||
|
&& matchsize == IP6T_ALIGN(sizeof(struct ip6t_icmp))
|
||
|
&& !(icmpinfo->invflags & ~IP6T_ICMP_INV);
|
||
|
}
|
||
|
|
||
|
/* The built-in targets: standard (NULL) and error. */
|
||
|
static struct ip6t_target ip6t_standard_target = {
|
||
|
.name = IP6T_STANDARD_TARGET,
|
||
|
};
|
||
|
|
||
|
static struct ip6t_target ip6t_error_target = {
|
||
|
.name = IP6T_ERROR_TARGET,
|
||
|
.target = ip6t_error,
|
||
|
};
|
||
|
|
||
|
static struct nf_sockopt_ops ip6t_sockopts = {
|
||
|
.pf = PF_INET6,
|
||
|
.set_optmin = IP6T_BASE_CTL,
|
||
|
.set_optmax = IP6T_SO_SET_MAX+1,
|
||
|
.set = do_ip6t_set_ctl,
|
||
|
.get_optmin = IP6T_BASE_CTL,
|
||
|
.get_optmax = IP6T_SO_GET_MAX+1,
|
||
|
.get = do_ip6t_get_ctl,
|
||
|
};
|
||
|
|
||
|
static struct ip6t_match tcp_matchstruct = {
|
||
|
.name = "tcp",
|
||
|
.match = &tcp_match,
|
||
|
.checkentry = &tcp_checkentry,
|
||
|
};
|
||
|
|
||
|
static struct ip6t_match udp_matchstruct = {
|
||
|
.name = "udp",
|
||
|
.match = &udp_match,
|
||
|
.checkentry = &udp_checkentry,
|
||
|
};
|
||
|
|
||
|
static struct ip6t_match icmp6_matchstruct = {
|
||
|
.name = "icmp6",
|
||
|
.match = &icmp6_match,
|
||
|
.checkentry = &icmp6_checkentry,
|
||
|
};
|
||
|
|
||
|
#ifdef CONFIG_PROC_FS
|
||
|
static inline int print_name(const char *i,
|
||
|
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",
|
||
|
i + sizeof(struct list_head));
|
||
|
if (*pos + namelen > length) {
|
||
|
/* Stop iterating */
|
||
|
return 1;
|
||
|
}
|
||
|
*pos += namelen;
|
||
|
}
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static inline int print_target(const struct ip6t_target *t,
|
||
|
off_t start_offset, char *buffer, int length,
|
||
|
off_t *pos, unsigned int *count)
|
||
|
{
|
||
|
if (t == &ip6t_standard_target || t == &ip6t_error_target)
|
||
|
return 0;
|
||
|
return print_name((char *)t, start_offset, buffer, length, pos, count);
|
||
|
}
|
||
|
|
||
|
static int ip6t_get_tables(char *buffer, char **start, off_t offset, int length)
|
||
|
{
|
||
|
off_t pos = 0;
|
||
|
unsigned int count = 0;
|
||
|
|
||
|
if (down_interruptible(&ip6t_mutex) != 0)
|
||
|
return 0;
|
||
|
|
||
|
LIST_FIND(&ip6t_tables, print_name, char *,
|
||
|
offset, buffer, length, &pos, &count);
|
||
|
|
||
|
up(&ip6t_mutex);
|
||
|
|
||
|
/* `start' hack - see fs/proc/generic.c line ~105 */
|
||
|
*start=(char *)((unsigned long)count-offset);
|
||
|
return pos;
|
||
|
}
|
||
|
|
||
|
static int ip6t_get_targets(char *buffer, char **start, off_t offset, int length)
|
||
|
{
|
||
|
off_t pos = 0;
|
||
|
unsigned int count = 0;
|
||
|
|
||
|
if (down_interruptible(&ip6t_mutex) != 0)
|
||
|
return 0;
|
||
|
|
||
|
LIST_FIND(&ip6t_target, print_target, struct ip6t_target *,
|
||
|
offset, buffer, length, &pos, &count);
|
||
|
|
||
|
up(&ip6t_mutex);
|
||
|
|
||
|
*start = (char *)((unsigned long)count - offset);
|
||
|
return pos;
|
||
|
}
|
||
|
|
||
|
static int ip6t_get_matches(char *buffer, char **start, off_t offset, int length)
|
||
|
{
|
||
|
off_t pos = 0;
|
||
|
unsigned int count = 0;
|
||
|
|
||
|
if (down_interruptible(&ip6t_mutex) != 0)
|
||
|
return 0;
|
||
|
|
||
|
LIST_FIND(&ip6t_match, print_name, char *,
|
||
|
offset, buffer, length, &pos, &count);
|
||
|
|
||
|
up(&ip6t_mutex);
|
||
|
|
||
|
*start = (char *)((unsigned long)count - offset);
|
||
|
return pos;
|
||
|
}
|
||
|
|
||
|
static struct { char *name; get_info_t *get_info; } ip6t_proc_entry[] =
|
||
|
{ { "ip6_tables_names", ip6t_get_tables },
|
||
|
{ "ip6_tables_targets", ip6t_get_targets },
|
||
|
{ "ip6_tables_matches", ip6t_get_matches },
|
||
|
{ NULL, NULL} };
|
||
|
#endif /*CONFIG_PROC_FS*/
|
||
|
|
||
|
static int __init init(void)
|
||
|
{
|
||
|
int ret;
|
||
|
|
||
|
/* Noone else will be downing sem now, so we won't sleep */
|
||
|
down(&ip6t_mutex);
|
||
|
list_append(&ip6t_target, &ip6t_standard_target);
|
||
|
list_append(&ip6t_target, &ip6t_error_target);
|
||
|
list_append(&ip6t_match, &tcp_matchstruct);
|
||
|
list_append(&ip6t_match, &udp_matchstruct);
|
||
|
list_append(&ip6t_match, &icmp6_matchstruct);
|
||
|
up(&ip6t_mutex);
|
||
|
|
||
|
/* Register setsockopt */
|
||
|
ret = nf_register_sockopt(&ip6t_sockopts);
|
||
|
if (ret < 0) {
|
||
|
duprintf("Unable to register sockopts.\n");
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_PROC_FS
|
||
|
{
|
||
|
struct proc_dir_entry *proc;
|
||
|
int i;
|
||
|
|
||
|
for (i = 0; ip6t_proc_entry[i].name; i++) {
|
||
|
proc = proc_net_create(ip6t_proc_entry[i].name, 0,
|
||
|
ip6t_proc_entry[i].get_info);
|
||
|
if (!proc) {
|
||
|
while (--i >= 0)
|
||
|
proc_net_remove(ip6t_proc_entry[i].name);
|
||
|
nf_unregister_sockopt(&ip6t_sockopts);
|
||
|
return -ENOMEM;
|
||
|
}
|
||
|
proc->owner = THIS_MODULE;
|
||
|
}
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
printk("ip6_tables: (C) 2000-2002 Netfilter core team\n");
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static void __exit fini(void)
|
||
|
{
|
||
|
nf_unregister_sockopt(&ip6t_sockopts);
|
||
|
#ifdef CONFIG_PROC_FS
|
||
|
{
|
||
|
int i;
|
||
|
for (i = 0; ip6t_proc_entry[i].name; i++)
|
||
|
proc_net_remove(ip6t_proc_entry[i].name);
|
||
|
}
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(ip6t_register_table);
|
||
|
EXPORT_SYMBOL(ip6t_unregister_table);
|
||
|
EXPORT_SYMBOL(ip6t_do_table);
|
||
|
EXPORT_SYMBOL(ip6t_register_match);
|
||
|
EXPORT_SYMBOL(ip6t_unregister_match);
|
||
|
EXPORT_SYMBOL(ip6t_register_target);
|
||
|
EXPORT_SYMBOL(ip6t_unregister_target);
|
||
|
EXPORT_SYMBOL(ip6t_ext_hdr);
|
||
|
|
||
|
module_init(init);
|
||
|
module_exit(fini);
|