Linux-2.6.33.2/net/ipv6/netfilter/ip6_tables.c
/*
* Packet matching code.
*
* Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
* Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/capability.h>
#include <linux/in.h>
#include <linux/skbuff.h>
#include <linux/kmod.h>
#include <linux/vmalloc.h>
#include <linux/netdevice.h>
#include <linux/module.h>
#include <linux/poison.h>
#include <linux/icmpv6.h>
#include <net/ipv6.h>
#include <net/compat.h>
#include <asm/uaccess.h>
#include <linux/mutex.h>
#include <linux/proc_fs.h>
#include <linux/err.h>
#include <linux/cpumask.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter/x_tables.h>
#include <net/netfilter/nf_log.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
MODULE_DESCRIPTION("IPv6 packet filter");
/*#define DEBUG_IP_FIREWALL*/
/*#define DEBUG_ALLOW_ALL*/ /* Useful for remote debugging */
/*#define DEBUG_IP_FIREWALL_USER*/
#ifdef DEBUG_IP_FIREWALL
#define dprintf(format, args...) printk(format , ## args)
#else
#define dprintf(format, args...)
#endif
#ifdef DEBUG_IP_FIREWALL_USER
#define duprintf(format, args...) printk(format , ## args)
#else
#define duprintf(format, args...)
#endif
#ifdef CONFIG_NETFILTER_DEBUG
#define IP_NF_ASSERT(x) \
do { \
if (!(x)) \
printk("IP_NF_ASSERT: %s:%s:%u\n", \
__func__, __FILE__, __LINE__); \
} while(0)
#else
#define IP_NF_ASSERT(x)
#endif
#if 0
/* All the better to debug you with... */
#define static
#define inline
#endif
/*
We keep a set of rules for each CPU, so we can avoid write-locking
them in the softirq when updating the counters and therefore
only need to read-lock in the softirq; doing a write_lock_bh() in user
context stops packets coming through and allows user context to read
the counters or update the rules.
Hence the start of any table is given by get_table() below. */
/* Check for an extension */
int
ip6t_ext_hdr(u8 nexthdr)
{
return ( (nexthdr == IPPROTO_HOPOPTS) ||
(nexthdr == IPPROTO_ROUTING) ||
(nexthdr == IPPROTO_FRAGMENT) ||
(nexthdr == IPPROTO_ESP) ||
(nexthdr == IPPROTO_AH) ||
(nexthdr == IPPROTO_NONE) ||
(nexthdr == IPPROTO_DSTOPTS) );
}
/* Returns whether matches rule or not. */
/* Performance critical - called for every packet */
static inline bool
ip6_packet_match(const struct sk_buff *skb,
const char *indev,
const char *outdev,
const struct ip6t_ip6 *ip6info,
unsigned int *protoff,
int *fragoff, bool *hotdrop)
{
unsigned long ret;
const struct ipv6hdr *ipv6 = ipv6_hdr(skb);
#define FWINV(bool, invflg) ((bool) ^ !!(ip6info->invflags & (invflg)))
if (FWINV(ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk,
&ip6info->src), IP6T_INV_SRCIP) ||
FWINV(ipv6_masked_addr_cmp(&ipv6->daddr, &ip6info->dmsk,
&ip6info->dst), IP6T_INV_DSTIP)) {
dprintf("Source or dest mismatch.\n");
/*
dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr,
ipinfo->smsk.s_addr, ipinfo->src.s_addr,
ipinfo->invflags & IP6T_INV_SRCIP ? " (INV)" : "");
dprintf("DST: %u. Mask: %u. Target: %u.%s\n", ip->daddr,
ipinfo->dmsk.s_addr, ipinfo->dst.s_addr,
ipinfo->invflags & IP6T_INV_DSTIP ? " (INV)" : "");*/
return false;
}
ret = ifname_compare_aligned(indev, ip6info->iniface, ip6info->iniface_mask);
if (FWINV(ret != 0, IP6T_INV_VIA_IN)) {
dprintf("VIA in mismatch (%s vs %s).%s\n",
indev, ip6info->iniface,
ip6info->invflags&IP6T_INV_VIA_IN ?" (INV)":"");
return false;
}
ret = ifname_compare_aligned(outdev, ip6info->outiface, ip6info->outiface_mask);
if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) {
dprintf("VIA out mismatch (%s vs %s).%s\n",
outdev, ip6info->outiface,
ip6info->invflags&IP6T_INV_VIA_OUT ?" (INV)":"");
return false;
}
/* ... might want to do something with class and flowlabel here ... */
/* look for the desired protocol header */
if((ip6info->flags & IP6T_F_PROTO)) {
int protohdr;
unsigned short _frag_off;
protohdr = ipv6_find_hdr(skb, protoff, -1, &_frag_off);
if (protohdr < 0) {
if (_frag_off == 0)
*hotdrop = true;
return false;
}
*fragoff = _frag_off;
dprintf("Packet protocol %hi ?= %s%hi.\n",
protohdr,
ip6info->invflags & IP6T_INV_PROTO ? "!":"",
ip6info->proto);
if (ip6info->proto == protohdr) {
if(ip6info->invflags & IP6T_INV_PROTO) {
return false;
}
return true;
}
/* We need match for the '-p all', too! */
if ((ip6info->proto != 0) &&
!(ip6info->invflags & IP6T_INV_PROTO))
return false;
}
return true;
}
/* should be ip6 safe */
static bool
ip6_checkentry(const struct ip6t_ip6 *ipv6)
{
if (ipv6->flags & ~IP6T_F_MASK) {
duprintf("Unknown flag bits set: %08X\n",
ipv6->flags & ~IP6T_F_MASK);
return false;
}
if (ipv6->invflags & ~IP6T_INV_MASK) {
duprintf("Unknown invflag bits set: %08X\n",
ipv6->invflags & ~IP6T_INV_MASK);
return false;
}
return true;
}
static unsigned int
ip6t_error(struct sk_buff *skb, const struct xt_target_param *par)
{
if (net_ratelimit())
printk("ip6_tables: error: `%s'\n",
(const char *)par->targinfo);
return NF_DROP;
}
/* Performance critical - called for every packet */
static inline bool
do_match(struct ip6t_entry_match *m, const struct sk_buff *skb,
struct xt_match_param *par)
{
par->match = m->u.kernel.match;
par->matchinfo = m->data;
/* Stop iteration if it doesn't match */
if (!m->u.kernel.match->match(skb, par))
return true;
else
return false;
}
static inline struct ip6t_entry *
get_entry(void *base, unsigned int offset)
{
return (struct ip6t_entry *)(base + offset);
}
/* All zeroes == unconditional rule. */
/* Mildly perf critical (only if packet tracing is on) */
static inline bool unconditional(const struct ip6t_ip6 *ipv6)
{
static const struct ip6t_ip6 uncond;
return memcmp(ipv6, &uncond, sizeof(uncond)) == 0;
}
#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
/* This cries for unification! */
static const char *const hooknames[] = {
[NF_INET_PRE_ROUTING] = "PREROUTING",
[NF_INET_LOCAL_IN] = "INPUT",
[NF_INET_FORWARD] = "FORWARD",
[NF_INET_LOCAL_OUT] = "OUTPUT",
[NF_INET_POST_ROUTING] = "POSTROUTING",
};
enum nf_ip_trace_comments {
NF_IP6_TRACE_COMMENT_RULE,
NF_IP6_TRACE_COMMENT_RETURN,
NF_IP6_TRACE_COMMENT_POLICY,
};
static const char *const comments[] = {
[NF_IP6_TRACE_COMMENT_RULE] = "rule",
[NF_IP6_TRACE_COMMENT_RETURN] = "return",
[NF_IP6_TRACE_COMMENT_POLICY] = "policy",
};
static struct nf_loginfo trace_loginfo = {
.type = NF_LOG_TYPE_LOG,
.u = {
.log = {
.level = 4,
.logflags = NF_LOG_MASK,
},
},
};
/* Mildly perf critical (only if packet tracing is on) */
static inline int
get_chainname_rulenum(struct ip6t_entry *s, struct ip6t_entry *e,
const char *hookname, const char **chainname,
const char **comment, unsigned int *rulenum)
{
struct ip6t_standard_target *t = (void *)ip6t_get_target(s);
if (strcmp(t->target.u.kernel.target->name, IP6T_ERROR_TARGET) == 0) {
/* Head of user chain: ERROR target with chainname */
*chainname = t->target.data;
(*rulenum) = 0;
} else if (s == e) {
(*rulenum)++;
if (s->target_offset == sizeof(struct ip6t_entry) &&
strcmp(t->target.u.kernel.target->name,
IP6T_STANDARD_TARGET) == 0 &&
t->verdict < 0 &&
unconditional(&s->ipv6)) {
/* Tail of chains: STANDARD target (return/policy) */
*comment = *chainname == hookname
? comments[NF_IP6_TRACE_COMMENT_POLICY]
: comments[NF_IP6_TRACE_COMMENT_RETURN];
}
return 1;
} else
(*rulenum)++;
return 0;
}
static void trace_packet(struct sk_buff *skb,
unsigned int hook,
const struct net_device *in,
const struct net_device *out,
const char *tablename,
struct xt_table_info *private,
struct ip6t_entry *e)
{
void *table_base;
const struct ip6t_entry *root;
const char *hookname, *chainname, *comment;
unsigned int rulenum = 0;
table_base = private->entries[smp_processor_id()];
root = get_entry(table_base, private->hook_entry[hook]);
hookname = chainname = hooknames[hook];
comment = comments[NF_IP6_TRACE_COMMENT_RULE];
IP6T_ENTRY_ITERATE(root,
private->size - private->hook_entry[hook],
get_chainname_rulenum,
e, hookname, &chainname, &comment, &rulenum);
nf_log_packet(AF_INET6, hook, skb, in, out, &trace_loginfo,
"TRACE: %s:%s:%s:%u ",
tablename, chainname, comment, rulenum);
}
#endif
static inline __pure struct ip6t_entry *
ip6t_next_entry(const struct ip6t_entry *entry)
{
return (void *)entry + entry->next_offset;
}
/* Returns one of the generic firewall policies, like NF_ACCEPT. */
unsigned int
ip6t_do_table(struct sk_buff *skb,
unsigned int hook,
const struct net_device *in,
const struct net_device *out,
struct xt_table *table)
{
#define tb_comefrom ((struct ip6t_entry *)table_base)->comefrom
static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
bool hotdrop = false;
/* Initializing verdict to NF_DROP keeps gcc happy. */
unsigned int verdict = NF_DROP;
const char *indev, *outdev;
void *table_base;
struct ip6t_entry *e, *back;
struct xt_table_info *private;
struct xt_match_param mtpar;
struct xt_target_param tgpar;
/* Initialization */
indev = in ? in->name : nulldevname;
outdev = out ? out->name : nulldevname;
/* We handle fragments by dealing with the first fragment as
* if it was a normal packet. All other fragments are treated
* normally, except that they will NEVER match rules that ask
* things we don't know, ie. tcp syn flag or ports). If the
* rule is also a fragment-specific rule, non-fragments won't
* match it. */
mtpar.hotdrop = &hotdrop;
mtpar.in = tgpar.in = in;
mtpar.out = tgpar.out = out;
mtpar.family = tgpar.family = NFPROTO_IPV6;
mtpar.hooknum = tgpar.hooknum = hook;
IP_NF_ASSERT(table->valid_hooks & (1 << hook));
xt_info_rdlock_bh();
private = table->private;
table_base = private->entries[smp_processor_id()];
e = get_entry(table_base, private->hook_entry[hook]);
/* For return from builtin chain */
back = get_entry(table_base, private->underflow[hook]);
do {
struct ip6t_entry_target *t;
IP_NF_ASSERT(e);
IP_NF_ASSERT(back);
if (!ip6_packet_match(skb, indev, outdev, &e->ipv6,
&mtpar.thoff, &mtpar.fragoff, &hotdrop) ||
IP6T_MATCH_ITERATE(e, do_match, skb, &mtpar) != 0) {
e = ip6t_next_entry(e);
continue;
}
ADD_COUNTER(e->counters,
ntohs(ipv6_hdr(skb)->payload_len) +
sizeof(struct ipv6hdr), 1);
t = ip6t_get_target(e);
IP_NF_ASSERT(t->u.kernel.target);
#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
/* The packet is traced: log it */
if (unlikely(skb->nf_trace))
trace_packet(skb, hook, in, out,
table->name, private, e);
#endif
/* 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 != ip6t_next_entry(e) &&
!(e->ipv6.flags & IP6T_F_GOTO)) {
/* Save old back ptr in next entry */
struct ip6t_entry *next = ip6t_next_entry(e);
next->comefrom = (void *)back - table_base;
/* set back pointer to next entry */
back = next;
}
e = get_entry(table_base, v);
continue;
}
/* Targets which reenter must return
abs. verdicts */
tgpar.target = t->u.kernel.target;
tgpar.targinfo = t->data;
#ifdef CONFIG_NETFILTER_DEBUG
tb_comefrom = 0xeeeeeeec;
#endif
verdict = t->u.kernel.target->target(skb, &tgpar);
#ifdef CONFIG_NETFILTER_DEBUG
if (tb_comefrom != 0xeeeeeeec && verdict == IP6T_CONTINUE) {
printk("Target %s reentered!\n",
t->u.kernel.target->name);
verdict = NF_DROP;
}
tb_comefrom = 0x57acc001;
#endif
if (verdict == IP6T_CONTINUE)
e = ip6t_next_entry(e);
else
/* Verdict */
break;
} while (!hotdrop);
#ifdef CONFIG_NETFILTER_DEBUG
tb_comefrom = NETFILTER_LINK_POISON;
#endif
xt_info_rdunlock_bh();
#ifdef DEBUG_ALLOW_ALL
return NF_ACCEPT;
#else
if (hotdrop)
return NF_DROP;
else return verdict;
#endif
#undef tb_comefrom
}
/* 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 xt_table_info *newinfo,
unsigned int valid_hooks, void *entry0)
{
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_INET_NUMHOOKS; hook++) {
unsigned int pos = newinfo->hook_entry[hook];
struct ip6t_entry *e = (struct ip6t_entry *)(entry0 + 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);
int visited = e->comefrom & (1 << hook);
if (e->comefrom & (1 << NF_INET_NUMHOOKS)) {
printk("iptables: loop hook %u pos %u %08X.\n",
hook, pos, e->comefrom);
return 0;
}
e->comefrom |= ((1 << hook) | (1 << NF_INET_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)) || visited) {
unsigned int oldpos, size;
if ((strcmp(t->target.u.user.name,
IP6T_STANDARD_TARGET) == 0) &&
t->verdict < -NF_MAX_VERDICT - 1) {
duprintf("mark_source_chains: bad "
"negative verdict (%i)\n",
t->verdict);
return 0;
}
/* Return: backtrack through the last
big jump. */
do {
e->comefrom ^= (1<<NF_INET_NUMHOOKS);
#ifdef DEBUG_IP_FIREWALL_USER
if (e->comefrom
& (1 << NF_INET_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 *)
(entry0 + pos);
} while (oldpos == pos + e->next_offset);
/* Move along one */
size = e->next_offset;
e = (struct ip6t_entry *)
(entry0 + 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) {
if (newpos > newinfo->size -
sizeof(struct ip6t_entry)) {
duprintf("mark_source_chains: "
"bad verdict (%i)\n",
newpos);
return 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 *)
(entry0 + newpos);
e->counters.pcnt = pos;
pos = newpos;
}
}
next:
duprintf("Finished chain %u\n", hook);
}
return 1;
}
static int
cleanup_match(struct ip6t_entry_match *m, unsigned int *i)
{
struct xt_mtdtor_param par;
if (i && (*i)-- == 0)
return 1;
par.match = m->u.kernel.match;
par.matchinfo = m->data;
par.family = NFPROTO_IPV6;
if (par.match->destroy != NULL)
par.match->destroy(&par);
module_put(par.match->me);
return 0;
}
static int
check_entry(struct ip6t_entry *e, const char *name)
{
struct ip6t_entry_target *t;
if (!ip6_checkentry(&e->ipv6)) {
duprintf("ip_tables: ip check failed %p %s.\n", e, name);
return -EINVAL;
}
if (e->target_offset + sizeof(struct ip6t_entry_target) >
e->next_offset)
return -EINVAL;
t = ip6t_get_target(e);
if (e->target_offset + t->u.target_size > e->next_offset)
return -EINVAL;
return 0;
}
static int check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par,
unsigned int *i)
{
const struct ip6t_ip6 *ipv6 = par->entryinfo;
int ret;
par->match = m->u.kernel.match;
par->matchinfo = m->data;
ret = xt_check_match(par, m->u.match_size - sizeof(*m),
ipv6->proto, ipv6->invflags & IP6T_INV_PROTO);
if (ret < 0) {
duprintf("ip_tables: check failed for `%s'.\n",
par.match->name);
return ret;
}
++*i;
return 0;
}
static int
find_check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par,
unsigned int *i)
{
struct xt_match *match;
int ret;
match = try_then_request_module(xt_find_match(AF_INET6, m->u.user.name,
m->u.user.revision),
"ip6t_%s", m->u.user.name);
if (IS_ERR(match) || !match) {
duprintf("find_check_match: `%s' not found\n", m->u.user.name);
return match ? PTR_ERR(match) : -ENOENT;
}
m->u.kernel.match = match;
ret = check_match(m, par, i);
if (ret)
goto err;
return 0;
err:
module_put(m->u.kernel.match->me);
return ret;
}
static int check_target(struct ip6t_entry *e, const char *name)
{
struct ip6t_entry_target *t = ip6t_get_target(e);
struct xt_tgchk_param par = {
.table = name,
.entryinfo = e,
.target = t->u.kernel.target,
.targinfo = t->data,
.hook_mask = e->comefrom,
.family = NFPROTO_IPV6,
};
int ret;
t = ip6t_get_target(e);
ret = xt_check_target(&par, t->u.target_size - sizeof(*t),
e->ipv6.proto, e->ipv6.invflags & IP6T_INV_PROTO);
if (ret < 0) {
duprintf("ip_tables: check failed for `%s'.\n",
t->u.kernel.target->name);
return ret;
}
return 0;
}
static int
find_check_entry(struct ip6t_entry *e, const char *name, unsigned int size,
unsigned int *i)
{
struct ip6t_entry_target *t;
struct xt_target *target;
int ret;
unsigned int j;
struct xt_mtchk_param mtpar;
ret = check_entry(e, name);
if (ret)
return ret;
j = 0;
mtpar.table = name;
mtpar.entryinfo = &e->ipv6;
mtpar.hook_mask = e->comefrom;
mtpar.family = NFPROTO_IPV6;
ret = IP6T_MATCH_ITERATE(e, find_check_match, &mtpar, &j);
if (ret != 0)
goto cleanup_matches;
t = ip6t_get_target(e);
target = try_then_request_module(xt_find_target(AF_INET6,
t->u.user.name,
t->u.user.revision),
"ip6t_%s", t->u.user.name);
if (IS_ERR(target) || !target) {
duprintf("find_check_entry: `%s' not found\n", t->u.user.name);
ret = target ? PTR_ERR(target) : -ENOENT;
goto cleanup_matches;
}
t->u.kernel.target = target;
ret = check_target(e, name);
if (ret)
goto err;
(*i)++;
return 0;
err:
module_put(t->u.kernel.target->me);
cleanup_matches:
IP6T_MATCH_ITERATE(e, cleanup_match, &j);
return ret;
}
static bool check_underflow(struct ip6t_entry *e)
{
const struct ip6t_entry_target *t;
unsigned int verdict;
if (!unconditional(&e->ipv6))
return false;
t = ip6t_get_target(e);
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
return false;
verdict = ((struct ip6t_standard_target *)t)->verdict;
verdict = -verdict - 1;
return verdict == NF_DROP || verdict == NF_ACCEPT;
}
static int
check_entry_size_and_hooks(struct ip6t_entry *e,
struct xt_table_info *newinfo,
unsigned char *base,
unsigned char *limit,
const unsigned int *hook_entries,
const unsigned int *underflows,
unsigned int valid_hooks,
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_INET_NUMHOOKS; h++) {
if (!(valid_hooks & (1 << h)))
continue;
if ((unsigned char *)e - base == hook_entries[h])
newinfo->hook_entry[h] = hook_entries[h];
if ((unsigned char *)e - base == underflows[h]) {
if (!check_underflow(e)) {
pr_err("Underflows must be unconditional and "
"use the STANDARD target with "
"ACCEPT/DROP\n");
return -EINVAL;
}
newinfo->underflow[h] = underflows[h];
}
}
/* Clear counters and comefrom */
e->counters = ((struct xt_counters) { 0, 0 });
e->comefrom = 0;
(*i)++;
return 0;
}
static int
cleanup_entry(struct ip6t_entry *e, unsigned int *i)
{
struct xt_tgdtor_param par;
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);
par.target = t->u.kernel.target;
par.targinfo = t->data;
par.family = NFPROTO_IPV6;
if (par.target->destroy != NULL)
par.target->destroy(&par);
module_put(par.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 xt_table_info *newinfo,
void *entry0,
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_INET_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(entry0, newinfo->size,
check_entry_size_and_hooks,
newinfo,
entry0,
entry0 + size,
hook_entries, underflows, valid_hooks, &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_INET_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, entry0))
return -ELOOP;
/* Finally, each sanity check must pass */
i = 0;
ret = IP6T_ENTRY_ITERATE(entry0, newinfo->size,
find_check_entry, name, size, &i);
if (ret != 0) {
IP6T_ENTRY_ITERATE(entry0, newinfo->size,
cleanup_entry, &i);
return ret;
}
/* And one copy for every other CPU */
for_each_possible_cpu(i) {
if (newinfo->entries[i] && newinfo->entries[i] != entry0)
memcpy(newinfo->entries[i], entry0, newinfo->size);
}
return ret;
}
/* Gets counters. */
static inline int
add_entry_to_counter(const struct ip6t_entry *e,
struct xt_counters total[],
unsigned int *i)
{
ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt);
(*i)++;
return 0;
}
static inline int
set_entry_to_counter(const struct ip6t_entry *e,
struct ip6t_counters total[],
unsigned int *i)
{
SET_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt);
(*i)++;
return 0;
}
static void
get_counters(const struct xt_table_info *t,
struct xt_counters counters[])
{
unsigned int cpu;
unsigned int i;
unsigned int curcpu;
/* Instead of clearing (by a previous call to memset())
* the counters and using adds, we set the counters
* with data used by 'current' CPU
*
* Bottom half has to be disabled to prevent deadlock
* if new softirq were to run and call ipt_do_table
*/
local_bh_disable();
curcpu = smp_processor_id();
i = 0;
IP6T_ENTRY_ITERATE(t->entries[curcpu],
t->size,
set_entry_to_counter,
counters,
&i);
for_each_possible_cpu(cpu) {
if (cpu == curcpu)
continue;
i = 0;
xt_info_wrlock(cpu);
IP6T_ENTRY_ITERATE(t->entries[cpu],
t->size,
add_entry_to_counter,
counters,
&i);
xt_info_wrunlock(cpu);
}
local_bh_enable();
}
static struct xt_counters *alloc_counters(struct xt_table *table)
{
unsigned int countersize;
struct xt_counters *counters;
struct xt_table_info *private = table->private;
/* We need atomic snapshot of counters: rest doesn't change
(other than comefrom, which userspace doesn't care
about). */
countersize = sizeof(struct xt_counters) * private->number;
counters = vmalloc_node(countersize, numa_node_id());
if (counters == NULL)
return ERR_PTR(-ENOMEM);
get_counters(private, counters);
return counters;
}
static int
copy_entries_to_user(unsigned int total_size,
struct xt_table *table,
void __user *userptr)
{
unsigned int off, num;
struct ip6t_entry *e;
struct xt_counters *counters;
const struct xt_table_info *private = table->private;
int ret = 0;
const void *loc_cpu_entry;
counters = alloc_counters(table);
if (IS_ERR(counters))
return PTR_ERR(counters);
/* choose the copy that is on our node/cpu, ...
* This choice is lazy (because current thread is
* allowed to migrate to another cpu)
*/
loc_cpu_entry = private->entries[raw_smp_processor_id()];
if (copy_to_user(userptr, loc_cpu_entry, 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;
const struct ip6t_entry_match *m;
const struct ip6t_entry_target *t;
e = (struct ip6t_entry *)(loc_cpu_entry + 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;
}
#ifdef CONFIG_COMPAT
static void compat_standard_from_user(void *dst, void *src)
{
int v = *(compat_int_t *)src;
if (v > 0)
v += xt_compat_calc_jump(AF_INET6, v);
memcpy(dst, &v, sizeof(v));
}
static int compat_standard_to_user(void __user *dst, void *src)
{
compat_int_t cv = *(int *)src;
if (cv > 0)
cv -= xt_compat_calc_jump(AF_INET6, cv);
return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
}
static inline int
compat_calc_match(struct ip6t_entry_match *m, int *size)
{
*size += xt_compat_match_offset(m->u.kernel.match);
return 0;
}
static int compat_calc_entry(struct ip6t_entry *e,
const struct xt_table_info *info,
void *base, struct xt_table_info *newinfo)
{
struct ip6t_entry_target *t;
unsigned int entry_offset;
int off, i, ret;
off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
entry_offset = (void *)e - base;
IP6T_MATCH_ITERATE(e, compat_calc_match, &off);
t = ip6t_get_target(e);
off += xt_compat_target_offset(t->u.kernel.target);
newinfo->size -= off;
ret = xt_compat_add_offset(AF_INET6, entry_offset, off);
if (ret)
return ret;
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
if (info->hook_entry[i] &&
(e < (struct ip6t_entry *)(base + info->hook_entry[i])))
newinfo->hook_entry[i] -= off;
if (info->underflow[i] &&
(e < (struct ip6t_entry *)(base + info->underflow[i])))
newinfo->underflow[i] -= off;
}
return 0;
}
static int compat_table_info(const struct xt_table_info *info,
struct xt_table_info *newinfo)
{
void *loc_cpu_entry;
if (!newinfo || !info)
return -EINVAL;
/* we dont care about newinfo->entries[] */
memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
newinfo->initial_entries = 0;
loc_cpu_entry = info->entries[raw_smp_processor_id()];
return IP6T_ENTRY_ITERATE(loc_cpu_entry, info->size,
compat_calc_entry, info, loc_cpu_entry,
newinfo);
}
#endif
static int get_info(struct net *net, void __user *user, int *len, int compat)
{
char name[IP6T_TABLE_MAXNAMELEN];
struct xt_table *t;
int ret;
if (*len != sizeof(struct ip6t_getinfo)) {
duprintf("length %u != %zu\n", *len,
sizeof(struct ip6t_getinfo));
return -EINVAL;
}
if (copy_from_user(name, user, sizeof(name)) != 0)
return -EFAULT;
name[IP6T_TABLE_MAXNAMELEN-1] = '\0';
#ifdef CONFIG_COMPAT
if (compat)
xt_compat_lock(AF_INET6);
#endif
t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name),
"ip6table_%s", name);
if (t && !IS_ERR(t)) {
struct ip6t_getinfo info;
const struct xt_table_info *private = t->private;
#ifdef CONFIG_COMPAT
struct xt_table_info tmp;
if (compat) {
ret = compat_table_info(private, &tmp);
xt_compat_flush_offsets(AF_INET6);
private = &tmp;
}
#endif
info.valid_hooks = t->valid_hooks;
memcpy(info.hook_entry, private->hook_entry,
sizeof(info.hook_entry));
memcpy(info.underflow, private->underflow,
sizeof(info.underflow));
info.num_entries = private->number;
info.size = private->size;
strcpy(info.name, name);
if (copy_to_user(user, &info, *len) != 0)
ret = -EFAULT;
else
ret = 0;
xt_table_unlock(t);
module_put(t->me);
} else
ret = t ? PTR_ERR(t) : -ENOENT;
#ifdef CONFIG_COMPAT
if (compat)
xt_compat_unlock(AF_INET6);
#endif
return ret;
}
static int
get_entries(struct net *net, struct ip6t_get_entries __user *uptr, int *len)
{
int ret;
struct ip6t_get_entries get;
struct xt_table *t;
if (*len < sizeof(get)) {
duprintf("get_entries: %u < %zu\n", *len, sizeof(get));
return -EINVAL;
}
if (copy_from_user(&get, uptr, sizeof(get)) != 0)
return -EFAULT;
if (*len != sizeof(struct ip6t_get_entries) + get.size) {
duprintf("get_entries: %u != %zu\n",
*len, sizeof(get) + get.size);
return -EINVAL;
}
t = xt_find_table_lock(net, AF_INET6, get.name);
if (t && !IS_ERR(t)) {
struct xt_table_info *private = t->private;
duprintf("t->private->number = %u\n", private->number);
if (get.size == private->size)
ret = copy_entries_to_user(private->size,
t, uptr->entrytable);
else {
duprintf("get_entries: I've got %u not %u!\n",
private->size, get.size);
ret = -EAGAIN;
}
module_put(t->me);
xt_table_unlock(t);
} else
ret = t ? PTR_ERR(t) : -ENOENT;
return ret;
}
static int
__do_replace(struct net *net, const char *name, unsigned int valid_hooks,
struct xt_table_info *newinfo, unsigned int num_counters,
void __user *counters_ptr)
{
int ret;
struct xt_table *t;
struct xt_table_info *oldinfo;
struct xt_counters *counters;
const void *loc_cpu_old_entry;
ret = 0;
counters = vmalloc_node(num_counters * sizeof(struct xt_counters),
numa_node_id());
if (!counters) {
ret = -ENOMEM;
goto out;
}
t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name),
"ip6table_%s", name);
if (!t || IS_ERR(t)) {
ret = t ? PTR_ERR(t) : -ENOENT;
goto free_newinfo_counters_untrans;
}
/* You lied! */
if (valid_hooks != t->valid_hooks) {
duprintf("Valid hook crap: %08X vs %08X\n",
valid_hooks, t->valid_hooks);
ret = -EINVAL;
goto put_module;
}
oldinfo = xt_replace_table(t, 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, and synchronize with replace */
get_counters(oldinfo, counters);
/* Decrease module usage counts and free resource */
loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()];
IP6T_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,
NULL);
xt_free_table_info(oldinfo);
if (copy_to_user(counters_ptr, counters,
sizeof(struct xt_counters) * num_counters) != 0)
ret = -EFAULT;
vfree(counters);
xt_table_unlock(t);
return ret;
put_module:
module_put(t->me);
xt_table_unlock(t);
free_newinfo_counters_untrans:
vfree(counters);
out:
return ret;
}
static int
do_replace(struct net *net, void __user *user, unsigned int len)
{
int ret;
struct ip6t_replace tmp;
struct xt_table_info *newinfo;
void *loc_cpu_entry;
if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
return -EFAULT;
/* overflow check */
if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
return -ENOMEM;
newinfo = xt_alloc_table_info(tmp.size);
if (!newinfo)
return -ENOMEM;
/* choose the copy that is on our node/cpu */
loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
tmp.size) != 0) {
ret = -EFAULT;
goto free_newinfo;
}
ret = translate_table(tmp.name, tmp.valid_hooks,
newinfo, loc_cpu_entry, tmp.size, tmp.num_entries,
tmp.hook_entry, tmp.underflow);
if (ret != 0)
goto free_newinfo;
duprintf("ip_tables: Translated table\n");
ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
tmp.num_counters, tmp.counters);
if (ret)
goto free_newinfo_untrans;
return 0;
free_newinfo_untrans:
IP6T_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL);
free_newinfo:
xt_free_table_info(newinfo);
return ret;
}
/* We're lazy, and add to the first CPU; overflow works its fey magic
* and everything is OK. */
static int
add_counter_to_entry(struct ip6t_entry *e,
const struct xt_counters addme[],
unsigned int *i)
{
ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt);
(*i)++;
return 0;
}
static int
do_add_counters(struct net *net, void __user *user, unsigned int len,
int compat)
{
unsigned int i, curcpu;
struct xt_counters_info tmp;
struct xt_counters *paddc;
unsigned int num_counters;
char *name;
int size;
void *ptmp;
struct xt_table *t;
const struct xt_table_info *private;
int ret = 0;
const void *loc_cpu_entry;
#ifdef CONFIG_COMPAT
struct compat_xt_counters_info compat_tmp;
if (compat) {
ptmp = &compat_tmp;
size = sizeof(struct compat_xt_counters_info);
} else
#endif
{
ptmp = &tmp;
size = sizeof(struct xt_counters_info);
}
if (copy_from_user(ptmp, user, size) != 0)
return -EFAULT;
#ifdef CONFIG_COMPAT
if (compat) {
num_counters = compat_tmp.num_counters;
name = compat_tmp.name;
} else
#endif
{
num_counters = tmp.num_counters;
name = tmp.name;
}
if (len != size + num_counters * sizeof(struct xt_counters))
return -EINVAL;
paddc = vmalloc_node(len - size, numa_node_id());
if (!paddc)
return -ENOMEM;
if (copy_from_user(paddc, user + size, len - size) != 0) {
ret = -EFAULT;
goto free;
}
t = xt_find_table_lock(net, AF_INET6, name);
if (!t || IS_ERR(t)) {
ret = t ? PTR_ERR(t) : -ENOENT;
goto free;
}
local_bh_disable();
private = t->private;
if (private->number != num_counters) {
ret = -EINVAL;
goto unlock_up_free;
}
i = 0;
/* Choose the copy that is on our node */
curcpu = smp_processor_id();
xt_info_wrlock(curcpu);
loc_cpu_entry = private->entries[curcpu];
IP6T_ENTRY_ITERATE(loc_cpu_entry,
private->size,
add_counter_to_entry,
paddc,
&i);
xt_info_wrunlock(curcpu);
unlock_up_free:
local_bh_enable();
xt_table_unlock(t);
module_put(t->me);
free:
vfree(paddc);
return ret;
}
#ifdef CONFIG_COMPAT
struct compat_ip6t_replace {
char name[IP6T_TABLE_MAXNAMELEN];
u32 valid_hooks;
u32 num_entries;
u32 size;
u32 hook_entry[NF_INET_NUMHOOKS];
u32 underflow[NF_INET_NUMHOOKS];
u32 num_counters;
compat_uptr_t counters; /* struct ip6t_counters * */
struct compat_ip6t_entry entries[0];
};
static int
compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr,
unsigned int *size, struct xt_counters *counters,
unsigned int *i)
{
struct ip6t_entry_target *t;
struct compat_ip6t_entry __user *ce;
u_int16_t target_offset, next_offset;
compat_uint_t origsize;
int ret;
ret = -EFAULT;
origsize = *size;
ce = (struct compat_ip6t_entry __user *)*dstptr;
if (copy_to_user(ce, e, sizeof(struct ip6t_entry)))
goto out;
if (copy_to_user(&ce->counters, &counters[*i], sizeof(counters[*i])))
goto out;
*dstptr += sizeof(struct compat_ip6t_entry);
*size -= sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
ret = IP6T_MATCH_ITERATE(e, xt_compat_match_to_user, dstptr, size);
target_offset = e->target_offset - (origsize - *size);
if (ret)
goto out;
t = ip6t_get_target(e);
ret = xt_compat_target_to_user(t, dstptr, size);
if (ret)
goto out;
ret = -EFAULT;
next_offset = e->next_offset - (origsize - *size);
if (put_user(target_offset, &ce->target_offset))
goto out;
if (put_user(next_offset, &ce->next_offset))
goto out;
(*i)++;
return 0;
out:
return ret;
}
static int
compat_find_calc_match(struct ip6t_entry_match *m,
const char *name,
const struct ip6t_ip6 *ipv6,
unsigned int hookmask,
int *size, unsigned int *i)
{
struct xt_match *match;
match = try_then_request_module(xt_find_match(AF_INET6, m->u.user.name,
m->u.user.revision),
"ip6t_%s", m->u.user.name);
if (IS_ERR(match) || !match) {
duprintf("compat_check_calc_match: `%s' not found\n",
m->u.user.name);
return match ? PTR_ERR(match) : -ENOENT;
}
m->u.kernel.match = match;
*size += xt_compat_match_offset(match);
(*i)++;
return 0;
}
static int
compat_release_match(struct ip6t_entry_match *m, unsigned int *i)
{
if (i && (*i)-- == 0)
return 1;
module_put(m->u.kernel.match->me);
return 0;
}
static int
compat_release_entry(struct compat_ip6t_entry *e, unsigned int *i)
{
struct ip6t_entry_target *t;
if (i && (*i)-- == 0)
return 1;
/* Cleanup all matches */
COMPAT_IP6T_MATCH_ITERATE(e, compat_release_match, NULL);
t = compat_ip6t_get_target(e);
module_put(t->u.kernel.target->me);
return 0;
}
static int
check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
struct xt_table_info *newinfo,
unsigned int *size,
unsigned char *base,
unsigned char *limit,
unsigned int *hook_entries,
unsigned int *underflows,
unsigned int *i,
const char *name)
{
struct ip6t_entry_target *t;
struct xt_target *target;
unsigned int entry_offset;
unsigned int j;
int ret, off, h;
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 ||
(unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit) {
duprintf("Bad offset %p, limit = %p\n", e, limit);
return -EINVAL;
}
if (e->next_offset < sizeof(struct compat_ip6t_entry) +
sizeof(struct compat_xt_entry_target)) {
duprintf("checking: element %p size %u\n",
e, e->next_offset);
return -EINVAL;
}
/* For purposes of check_entry casting the compat entry is fine */
ret = check_entry((struct ip6t_entry *)e, name);
if (ret)
return ret;
off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
entry_offset = (void *)e - (void *)base;
j = 0;
ret = COMPAT_IP6T_MATCH_ITERATE(e, compat_find_calc_match, name,
&e->ipv6, e->comefrom, &off, &j);
if (ret != 0)
goto release_matches;
t = compat_ip6t_get_target(e);
target = try_then_request_module(xt_find_target(AF_INET6,
t->u.user.name,
t->u.user.revision),
"ip6t_%s", t->u.user.name);
if (IS_ERR(target) || !target) {
duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
t->u.user.name);
ret = target ? PTR_ERR(target) : -ENOENT;
goto release_matches;
}
t->u.kernel.target = target;
off += xt_compat_target_offset(target);
*size += off;
ret = xt_compat_add_offset(AF_INET6, entry_offset, off);
if (ret)
goto out;
/* Check hooks & underflows */
for (h = 0; h < NF_INET_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];
}
/* Clear counters and comefrom */
memset(&e->counters, 0, sizeof(e->counters));
e->comefrom = 0;
(*i)++;
return 0;
out:
module_put(t->u.kernel.target->me);
release_matches:
IP6T_MATCH_ITERATE(e, compat_release_match, &j);
return ret;
}
static int
compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
unsigned int *size, const char *name,
struct xt_table_info *newinfo, unsigned char *base)
{
struct ip6t_entry_target *t;
struct xt_target *target;
struct ip6t_entry *de;
unsigned int origsize;
int ret, h;
ret = 0;
origsize = *size;
de = (struct ip6t_entry *)*dstptr;
memcpy(de, e, sizeof(struct ip6t_entry));
memcpy(&de->counters, &e->counters, sizeof(e->counters));
*dstptr += sizeof(struct ip6t_entry);
*size += sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
ret = COMPAT_IP6T_MATCH_ITERATE(e, xt_compat_match_from_user,
dstptr, size);
if (ret)
return ret;
de->target_offset = e->target_offset - (origsize - *size);
t = compat_ip6t_get_target(e);
target = t->u.kernel.target;
xt_compat_target_from_user(t, dstptr, size);
de->next_offset = e->next_offset - (origsize - *size);
for (h = 0; h < NF_INET_NUMHOOKS; h++) {
if ((unsigned char *)de - base < newinfo->hook_entry[h])
newinfo->hook_entry[h] -= origsize - *size;
if ((unsigned char *)de - base < newinfo->underflow[h])
newinfo->underflow[h] -= origsize - *size;
}
return ret;
}
static int compat_check_entry(struct ip6t_entry *e, const char *name,
unsigned int *i)
{
unsigned int j;
int ret;
struct xt_mtchk_param mtpar;
j = 0;
mtpar.table = name;
mtpar.entryinfo = &e->ipv6;
mtpar.hook_mask = e->comefrom;
mtpar.family = NFPROTO_IPV6;
ret = IP6T_MATCH_ITERATE(e, check_match, &mtpar, &j);
if (ret)
goto cleanup_matches;
ret = check_target(e, name);
if (ret)
goto cleanup_matches;
(*i)++;
return 0;
cleanup_matches:
IP6T_MATCH_ITERATE(e, cleanup_match, &j);
return ret;
}
static int
translate_compat_table(const char *name,
unsigned int valid_hooks,
struct xt_table_info **pinfo,
void **pentry0,
unsigned int total_size,
unsigned int number,
unsigned int *hook_entries,
unsigned int *underflows)
{
unsigned int i, j;
struct xt_table_info *newinfo, *info;
void *pos, *entry0, *entry1;
unsigned int size;
int ret;
info = *pinfo;
entry0 = *pentry0;
size = total_size;
info->number = number;
/* Init all hooks to impossible value. */
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
info->hook_entry[i] = 0xFFFFFFFF;
info->underflow[i] = 0xFFFFFFFF;
}
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(AF_INET6);
/* Walk through entries, checking offsets. */
ret = COMPAT_IP6T_ENTRY_ITERATE(entry0, total_size,
check_compat_entry_size_and_hooks,
info, &size, entry0,
entry0 + total_size,
hook_entries, underflows, &j, name);
if (ret != 0)
goto out_unlock;
ret = -EINVAL;
if (j != number) {
duprintf("translate_compat_table: %u not %u entries\n",
j, number);
goto out_unlock;
}
/* Check hooks all assigned */
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
/* Only hooks which are valid */
if (!(valid_hooks & (1 << i)))
continue;
if (info->hook_entry[i] == 0xFFFFFFFF) {
duprintf("Invalid hook entry %u %u\n",
i, hook_entries[i]);
goto out_unlock;
}
if (info->underflow[i] == 0xFFFFFFFF) {
duprintf("Invalid underflow %u %u\n",
i, underflows[i]);
goto out_unlock;
}
}
ret = -ENOMEM;
newinfo = xt_alloc_table_info(size);
if (!newinfo)
goto out_unlock;
newinfo->number = number;
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
newinfo->hook_entry[i] = info->hook_entry[i];
newinfo->underflow[i] = info->underflow[i];
}
entry1 = newinfo->entries[raw_smp_processor_id()];
pos = entry1;
size = total_size;
ret = COMPAT_IP6T_ENTRY_ITERATE(entry0, total_size,
compat_copy_entry_from_user,
&pos, &size, name, newinfo, entry1);
xt_compat_flush_offsets(AF_INET6);
xt_compat_unlock(AF_INET6);
if (ret)
goto free_newinfo;
ret = -ELOOP;
if (!mark_source_chains(newinfo, valid_hooks, entry1))
goto free_newinfo;
i = 0;
ret = IP6T_ENTRY_ITERATE(entry1, newinfo->size, compat_check_entry,
name, &i);
if (ret) {
j -= i;
COMPAT_IP6T_ENTRY_ITERATE_CONTINUE(entry0, newinfo->size, i,
compat_release_entry, &j);
IP6T_ENTRY_ITERATE(entry1, newinfo->size, cleanup_entry, &i);
xt_free_table_info(newinfo);
return ret;
}
/* And one copy for every other CPU */
for_each_possible_cpu(i)
if (newinfo->entries[i] && newinfo->entries[i] != entry1)
memcpy(newinfo->entries[i], entry1, newinfo->size);
*pinfo = newinfo;
*pentry0 = entry1;
xt_free_table_info(info);
return 0;
free_newinfo:
xt_free_table_info(newinfo);
out:
COMPAT_IP6T_ENTRY_ITERATE(entry0, total_size, compat_release_entry, &j);
return ret;
out_unlock:
xt_compat_flush_offsets(AF_INET6);
xt_compat_unlock(AF_INET6);
goto out;
}
static int
compat_do_replace(struct net *net, void __user *user, unsigned int len)
{
int ret;
struct compat_ip6t_replace tmp;
struct xt_table_info *newinfo;
void *loc_cpu_entry;
if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
return -EFAULT;
/* overflow check */
if (tmp.size >= INT_MAX / num_possible_cpus())
return -ENOMEM;
if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
return -ENOMEM;
newinfo = xt_alloc_table_info(tmp.size);
if (!newinfo)
return -ENOMEM;
/* choose the copy that is on our node/cpu */
loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
tmp.size) != 0) {
ret = -EFAULT;
goto free_newinfo;
}
ret = translate_compat_table(tmp.name, tmp.valid_hooks,
&newinfo, &loc_cpu_entry, tmp.size,
tmp.num_entries, tmp.hook_entry,
tmp.underflow);
if (ret != 0)
goto free_newinfo;
duprintf("compat_do_replace: Translated table\n");
ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
tmp.num_counters, compat_ptr(tmp.counters));
if (ret)
goto free_newinfo_untrans;
return 0;
free_newinfo_untrans:
IP6T_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL);
free_newinfo:
xt_free_table_info(newinfo);
return ret;
}
static int
compat_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 = compat_do_replace(sock_net(sk), user, len);
break;
case IP6T_SO_SET_ADD_COUNTERS:
ret = do_add_counters(sock_net(sk), user, len, 1);
break;
default:
duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd);
ret = -EINVAL;
}
return ret;
}
struct compat_ip6t_get_entries {
char name[IP6T_TABLE_MAXNAMELEN];
compat_uint_t size;
struct compat_ip6t_entry entrytable[0];
};
static int
compat_copy_entries_to_user(unsigned int total_size, struct xt_table *table,
void __user *userptr)
{
struct xt_counters *counters;
const struct xt_table_info *private = table->private;
void __user *pos;
unsigned int size;
int ret = 0;
const void *loc_cpu_entry;
unsigned int i = 0;
counters = alloc_counters(table);
if (IS_ERR(counters))
return PTR_ERR(counters);
/* choose the copy that is on our node/cpu, ...
* This choice is lazy (because current thread is
* allowed to migrate to another cpu)
*/
loc_cpu_entry = private->entries[raw_smp_processor_id()];
pos = userptr;
size = total_size;
ret = IP6T_ENTRY_ITERATE(loc_cpu_entry, total_size,
compat_copy_entry_to_user,
&pos, &size, counters, &i);
vfree(counters);
return ret;
}
static int
compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr,
int *len)
{
int ret;
struct compat_ip6t_get_entries get;
struct xt_table *t;
if (*len < sizeof(get)) {
duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get));
return -EINVAL;
}
if (copy_from_user(&get, uptr, sizeof(get)) != 0)
return -EFAULT;
if (*len != sizeof(struct compat_ip6t_get_entries) + get.size) {
duprintf("compat_get_entries: %u != %zu\n",
*len, sizeof(get) + get.size);
return -EINVAL;
}
xt_compat_lock(AF_INET6);
t = xt_find_table_lock(net, AF_INET6, get.name);
if (t && !IS_ERR(t)) {
const struct xt_table_info *private = t->private;
struct xt_table_info info;
duprintf("t->private->number = %u\n", private->number);
ret = compat_table_info(private, &info);
if (!ret && get.size == info.size) {
ret = compat_copy_entries_to_user(private->size,
t, uptr->entrytable);
} else if (!ret) {
duprintf("compat_get_entries: I've got %u not %u!\n",
private->size, get.size);
ret = -EAGAIN;
}
xt_compat_flush_offsets(AF_INET6);
module_put(t->me);
xt_table_unlock(t);
} else
ret = t ? PTR_ERR(t) : -ENOENT;
xt_compat_unlock(AF_INET6);
return ret;
}
static int do_ip6t_get_ctl(struct sock *, int, void __user *, int *);
static int
compat_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:
ret = get_info(sock_net(sk), user, len, 1);
break;
case IP6T_SO_GET_ENTRIES:
ret = compat_get_entries(sock_net(sk), user, len);
break;
default:
ret = do_ip6t_get_ctl(sk, cmd, user, len);
}
return ret;
}
#endif
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(sock_net(sk), user, len);
break;
case IP6T_SO_SET_ADD_COUNTERS:
ret = do_add_counters(sock_net(sk), user, len, 0);
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:
ret = get_info(sock_net(sk), user, len, 0);
break;
case IP6T_SO_GET_ENTRIES:
ret = get_entries(sock_net(sk), user, len);
break;
case IP6T_SO_GET_REVISION_MATCH:
case IP6T_SO_GET_REVISION_TARGET: {
struct ip6t_get_revision rev;
int target;
if (*len != sizeof(rev)) {
ret = -EINVAL;
break;
}
if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
ret = -EFAULT;
break;
}
if (cmd == IP6T_SO_GET_REVISION_TARGET)
target = 1;
else
target = 0;
try_then_request_module(xt_find_revision(AF_INET6, rev.name,
rev.revision,
target, &ret),
"ip6t_%s", rev.name);
break;
}
default:
duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd);
ret = -EINVAL;
}
return ret;
}
struct xt_table *ip6t_register_table(struct net *net,
const struct xt_table *table,
const struct ip6t_replace *repl)
{
int ret;
struct xt_table_info *newinfo;
struct xt_table_info bootstrap
= { 0, 0, 0, { 0 }, { 0 }, { } };
void *loc_cpu_entry;
struct xt_table *new_table;
newinfo = xt_alloc_table_info(repl->size);
if (!newinfo) {
ret = -ENOMEM;
goto out;
}
/* choose the copy on our node/cpu, but dont care about preemption */
loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
memcpy(loc_cpu_entry, repl->entries, repl->size);
ret = translate_table(table->name, table->valid_hooks,
newinfo, loc_cpu_entry, repl->size,
repl->num_entries,
repl->hook_entry,
repl->underflow);
if (ret != 0)
goto out_free;
new_table = xt_register_table(net, table, &bootstrap, newinfo);
if (IS_ERR(new_table)) {
ret = PTR_ERR(new_table);
goto out_free;
}
return new_table;
out_free:
xt_free_table_info(newinfo);
out:
return ERR_PTR(ret);
}
void ip6t_unregister_table(struct xt_table *table)
{
struct xt_table_info *private;
void *loc_cpu_entry;
struct module *table_owner = table->me;
private = xt_unregister_table(table);
/* Decrease module usage counts and free resources */
loc_cpu_entry = private->entries[raw_smp_processor_id()];
IP6T_ENTRY_ITERATE(loc_cpu_entry, private->size, cleanup_entry, NULL);
if (private->number > private->initial_entries)
module_put(table_owner);
xt_free_table_info(private);
}
/* Returns 1 if the type and code is matched by the range, 0 otherwise */
static inline bool
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,
bool invert)
{
return (type == test_type && code >= min_code && code <= max_code)
^ invert;
}
static bool
icmp6_match(const struct sk_buff *skb, const struct xt_match_param *par)
{
const struct icmp6hdr *ic;
struct icmp6hdr _icmph;
const struct ip6t_icmp *icmpinfo = par->matchinfo;
/* Must not be a fragment. */
if (par->fragoff != 0)
return false;
ic = skb_header_pointer(skb, par->thoff, sizeof(_icmph), &_icmph);
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");
*par->hotdrop = true;
return false;
}
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 bool icmp6_checkentry(const struct xt_mtchk_param *par)
{
const struct ip6t_icmp *icmpinfo = par->matchinfo;
/* Must specify no unknown invflags */
return !(icmpinfo->invflags & ~IP6T_ICMP_INV);
}
/* The built-in targets: standard (NULL) and error. */
static struct xt_target ip6t_standard_target __read_mostly = {
.name = IP6T_STANDARD_TARGET,
.targetsize = sizeof(int),
.family = NFPROTO_IPV6,
#ifdef CONFIG_COMPAT
.compatsize = sizeof(compat_int_t),
.compat_from_user = compat_standard_from_user,
.compat_to_user = compat_standard_to_user,
#endif
};
static struct xt_target ip6t_error_target __read_mostly = {
.name = IP6T_ERROR_TARGET,
.target = ip6t_error,
.targetsize = IP6T_FUNCTION_MAXNAMELEN,
.family = NFPROTO_IPV6,
};
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,
#ifdef CONFIG_COMPAT
.compat_set = compat_do_ip6t_set_ctl,
#endif
.get_optmin = IP6T_BASE_CTL,
.get_optmax = IP6T_SO_GET_MAX+1,
.get = do_ip6t_get_ctl,
#ifdef CONFIG_COMPAT
.compat_get = compat_do_ip6t_get_ctl,
#endif
.owner = THIS_MODULE,
};
static struct xt_match icmp6_matchstruct __read_mostly = {
.name = "icmp6",
.match = icmp6_match,
.matchsize = sizeof(struct ip6t_icmp),
.checkentry = icmp6_checkentry,
.proto = IPPROTO_ICMPV6,
.family = NFPROTO_IPV6,
};
static int __net_init ip6_tables_net_init(struct net *net)
{
return xt_proto_init(net, NFPROTO_IPV6);
}
static void __net_exit ip6_tables_net_exit(struct net *net)
{
xt_proto_fini(net, NFPROTO_IPV6);
}
static struct pernet_operations ip6_tables_net_ops = {
.init = ip6_tables_net_init,
.exit = ip6_tables_net_exit,
};
static int __init ip6_tables_init(void)
{
int ret;
ret = register_pernet_subsys(&ip6_tables_net_ops);
if (ret < 0)
goto err1;
/* Noone else will be downing sem now, so we won't sleep */
ret = xt_register_target(&ip6t_standard_target);
if (ret < 0)
goto err2;
ret = xt_register_target(&ip6t_error_target);
if (ret < 0)
goto err3;
ret = xt_register_match(&icmp6_matchstruct);
if (ret < 0)
goto err4;
/* Register setsockopt */
ret = nf_register_sockopt(&ip6t_sockopts);
if (ret < 0)
goto err5;
printk(KERN_INFO "ip6_tables: (C) 2000-2006 Netfilter Core Team\n");
return 0;
err5:
xt_unregister_match(&icmp6_matchstruct);
err4:
xt_unregister_target(&ip6t_error_target);
err3:
xt_unregister_target(&ip6t_standard_target);
err2:
unregister_pernet_subsys(&ip6_tables_net_ops);
err1:
return ret;
}
static void __exit ip6_tables_fini(void)
{
nf_unregister_sockopt(&ip6t_sockopts);
xt_unregister_match(&icmp6_matchstruct);
xt_unregister_target(&ip6t_error_target);
xt_unregister_target(&ip6t_standard_target);
unregister_pernet_subsys(&ip6_tables_net_ops);
}
/*
* find the offset to specified header or the protocol number of last header
* if target < 0. "last header" is transport protocol header, ESP, or
* "No next header".
*
* If target header is found, its offset is set in *offset and return protocol
* number. Otherwise, return -1.
*
* If the first fragment doesn't contain the final protocol header or
* NEXTHDR_NONE it is considered invalid.
*
* Note that non-1st fragment is special case that "the protocol number
* of last header" is "next header" field in Fragment header. In this case,
* *offset is meaningless and fragment offset is stored in *fragoff if fragoff
* isn't NULL.
*
*/
int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
int target, unsigned short *fragoff)
{
unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr);
u8 nexthdr = ipv6_hdr(skb)->nexthdr;
unsigned int len = skb->len - start;
if (fragoff)
*fragoff = 0;
while (nexthdr != target) {
struct ipv6_opt_hdr _hdr, *hp;
unsigned int hdrlen;
if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) {
if (target < 0)
break;
return -ENOENT;
}
hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr);
if (hp == NULL)
return -EBADMSG;
if (nexthdr == NEXTHDR_FRAGMENT) {
unsigned short _frag_off;
__be16 *fp;
fp = skb_header_pointer(skb,
start+offsetof(struct frag_hdr,
frag_off),
sizeof(_frag_off),
&_frag_off);
if (fp == NULL)
return -EBADMSG;
_frag_off = ntohs(*fp) & ~0x7;
if (_frag_off) {
if (target < 0 &&
((!ipv6_ext_hdr(hp->nexthdr)) ||
hp->nexthdr == NEXTHDR_NONE)) {
if (fragoff)
*fragoff = _frag_off;
return hp->nexthdr;
}
return -ENOENT;
}
hdrlen = 8;
} else if (nexthdr == NEXTHDR_AUTH)
hdrlen = (hp->hdrlen + 2) << 2;
else
hdrlen = ipv6_optlen(hp);
nexthdr = hp->nexthdr;
len -= hdrlen;
start += hdrlen;
}
*offset = start;
return nexthdr;
}
EXPORT_SYMBOL(ip6t_register_table);
EXPORT_SYMBOL(ip6t_unregister_table);
EXPORT_SYMBOL(ip6t_do_table);
EXPORT_SYMBOL(ip6t_ext_hdr);
EXPORT_SYMBOL(ipv6_find_hdr);
module_init(ip6_tables_init);
module_exit(ip6_tables_fini);