// SPDX-License-Identifier: GPL-2.0-only
|
/*
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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) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
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* Copyright (c) 2006-2010 Patrick McHardy <kaber@trash.net>
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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|
#include <linux/kernel.h>
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#include <linux/capability.h>
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#include <linux/in.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>
|
#include <linux/netdevice.h>
|
#include <linux/module.h>
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#include <linux/poison.h>
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#include <linux/icmpv6.h>
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#include <net/ipv6.h>
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#include <net/compat.h>
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#include <linux/uaccess.h>
|
#include <linux/mutex.h>
|
#include <linux/proc_fs.h>
|
#include <linux/err.h>
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#include <linux/cpumask.h>
|
|
#include <linux/netfilter_ipv6/ip6_tables.h>
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#include <linux/netfilter/x_tables.h>
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#include <net/netfilter/nf_log.h>
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#include "../../netfilter/xt_repldata.h"
|
|
MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
|
MODULE_DESCRIPTION("IPv6 packet filter");
|
MODULE_ALIAS("ip6t_icmp6");
|
|
void *ip6t_alloc_initial_table(const struct xt_table *info)
|
{
|
return xt_alloc_initial_table(ip6t, IP6T);
|
}
|
EXPORT_SYMBOL_GPL(ip6t_alloc_initial_table);
|
|
/* 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);
|
|
if (NF_INVF(ip6info, IP6T_INV_SRCIP,
|
ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk,
|
&ip6info->src)) ||
|
NF_INVF(ip6info, IP6T_INV_DSTIP,
|
ipv6_masked_addr_cmp(&ipv6->daddr, &ip6info->dmsk,
|
&ip6info->dst)))
|
return false;
|
|
ret = ifname_compare_aligned(indev, ip6info->iniface, ip6info->iniface_mask);
|
|
if (NF_INVF(ip6info, IP6T_INV_VIA_IN, ret != 0))
|
return false;
|
|
ret = ifname_compare_aligned(outdev, ip6info->outiface, ip6info->outiface_mask);
|
|
if (NF_INVF(ip6info, IP6T_INV_VIA_OUT, ret != 0))
|
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, NULL);
|
if (protohdr < 0) {
|
if (_frag_off == 0)
|
*hotdrop = true;
|
return false;
|
}
|
*fragoff = _frag_off;
|
|
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)
|
return false;
|
if (ipv6->invflags & ~IP6T_INV_MASK)
|
return false;
|
|
return true;
|
}
|
|
static unsigned int
|
ip6t_error(struct sk_buff *skb, const struct xt_action_param *par)
|
{
|
net_info_ratelimited("error: `%s'\n", (const char *)par->targinfo);
|
|
return NF_DROP;
|
}
|
|
static inline struct ip6t_entry *
|
get_entry(const 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_entry *e)
|
{
|
static const struct ip6t_ip6 uncond;
|
|
return e->target_offset == sizeof(struct ip6t_entry) &&
|
memcmp(&e->ipv6, &uncond, sizeof(uncond)) == 0;
|
}
|
|
static inline const struct xt_entry_target *
|
ip6t_get_target_c(const struct ip6t_entry *e)
|
{
|
return ip6t_get_target((struct ip6t_entry *)e);
|
}
|
|
#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
|
/* 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 const struct nf_loginfo trace_loginfo = {
|
.type = NF_LOG_TYPE_LOG,
|
.u = {
|
.log = {
|
.level = LOGLEVEL_WARNING,
|
.logflags = NF_LOG_DEFAULT_MASK,
|
},
|
},
|
};
|
|
/* Mildly perf critical (only if packet tracing is on) */
|
static inline int
|
get_chainname_rulenum(const struct ip6t_entry *s, const struct ip6t_entry *e,
|
const char *hookname, const char **chainname,
|
const char **comment, unsigned int *rulenum)
|
{
|
const struct xt_standard_target *t = (void *)ip6t_get_target_c(s);
|
|
if (strcmp(t->target.u.kernel.target->name, XT_ERROR_TARGET) == 0) {
|
/* Head of user chain: ERROR target with chainname */
|
*chainname = t->target.data;
|
(*rulenum) = 0;
|
} else if (s == e) {
|
(*rulenum)++;
|
|
if (unconditional(s) &&
|
strcmp(t->target.u.kernel.target->name,
|
XT_STANDARD_TARGET) == 0 &&
|
t->verdict < 0) {
|
/* 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 net *net,
|
const struct sk_buff *skb,
|
unsigned int hook,
|
const struct net_device *in,
|
const struct net_device *out,
|
const char *tablename,
|
const struct xt_table_info *private,
|
const struct ip6t_entry *e)
|
{
|
const struct ip6t_entry *root;
|
const char *hookname, *chainname, *comment;
|
const struct ip6t_entry *iter;
|
unsigned int rulenum = 0;
|
|
root = get_entry(private->entries, private->hook_entry[hook]);
|
|
hookname = chainname = hooknames[hook];
|
comment = comments[NF_IP6_TRACE_COMMENT_RULE];
|
|
xt_entry_foreach(iter, root, private->size - private->hook_entry[hook])
|
if (get_chainname_rulenum(iter, e, hookname,
|
&chainname, &comment, &rulenum) != 0)
|
break;
|
|
nf_log_trace(net, AF_INET6, hook, skb, in, out, &trace_loginfo,
|
"TRACE: %s:%s:%s:%u ",
|
tablename, chainname, comment, rulenum);
|
}
|
#endif
|
|
static inline 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,
|
const struct nf_hook_state *state,
|
struct xt_table *table)
|
{
|
unsigned int hook = state->hook;
|
static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
|
/* Initializing verdict to NF_DROP keeps gcc happy. */
|
unsigned int verdict = NF_DROP;
|
const char *indev, *outdev;
|
const void *table_base;
|
struct ip6t_entry *e, **jumpstack;
|
unsigned int stackidx, cpu;
|
const struct xt_table_info *private;
|
struct xt_action_param acpar;
|
unsigned int addend;
|
|
/* Initialization */
|
stackidx = 0;
|
indev = state->in ? state->in->name : nulldevname;
|
outdev = state->out ? state->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. */
|
acpar.fragoff = 0;
|
acpar.hotdrop = false;
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acpar.state = state;
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|
WARN_ON(!(table->valid_hooks & (1 << hook)));
|
|
local_bh_disable();
|
addend = xt_write_recseq_begin();
|
private = READ_ONCE(table->private); /* Address dependency. */
|
cpu = smp_processor_id();
|
table_base = private->entries;
|
jumpstack = (struct ip6t_entry **)private->jumpstack[cpu];
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|
/* Switch to alternate jumpstack if we're being invoked via TEE.
|
* TEE issues XT_CONTINUE verdict on original skb so we must not
|
* clobber the jumpstack.
|
*
|
* For recursion via REJECT or SYNPROXY the stack will be clobbered
|
* but it is no problem since absolute verdict is issued by these.
|
*/
|
if (static_key_false(&xt_tee_enabled))
|
jumpstack += private->stacksize * __this_cpu_read(nf_skb_duplicated);
|
|
e = get_entry(table_base, private->hook_entry[hook]);
|
|
do {
|
const struct xt_entry_target *t;
|
const struct xt_entry_match *ematch;
|
struct xt_counters *counter;
|
|
WARN_ON(!e);
|
acpar.thoff = 0;
|
if (!ip6_packet_match(skb, indev, outdev, &e->ipv6,
|
&acpar.thoff, &acpar.fragoff, &acpar.hotdrop)) {
|
no_match:
|
e = ip6t_next_entry(e);
|
continue;
|
}
|
|
xt_ematch_foreach(ematch, e) {
|
acpar.match = ematch->u.kernel.match;
|
acpar.matchinfo = ematch->data;
|
if (!acpar.match->match(skb, &acpar))
|
goto no_match;
|
}
|
|
counter = xt_get_this_cpu_counter(&e->counters);
|
ADD_COUNTER(*counter, skb->len, 1);
|
|
t = ip6t_get_target_c(e);
|
WARN_ON(!t->u.kernel.target);
|
|
#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
|
/* The packet is traced: log it */
|
if (unlikely(skb->nf_trace))
|
trace_packet(state->net, skb, hook, state->in,
|
state->out, table->name, private, e);
|
#endif
|
/* Standard target? */
|
if (!t->u.kernel.target->target) {
|
int v;
|
|
v = ((struct xt_standard_target *)t)->verdict;
|
if (v < 0) {
|
/* Pop from stack? */
|
if (v != XT_RETURN) {
|
verdict = (unsigned int)(-v) - 1;
|
break;
|
}
|
if (stackidx == 0)
|
e = get_entry(table_base,
|
private->underflow[hook]);
|
else
|
e = ip6t_next_entry(jumpstack[--stackidx]);
|
continue;
|
}
|
if (table_base + v != ip6t_next_entry(e) &&
|
!(e->ipv6.flags & IP6T_F_GOTO)) {
|
if (unlikely(stackidx >= private->stacksize)) {
|
verdict = NF_DROP;
|
break;
|
}
|
jumpstack[stackidx++] = e;
|
}
|
|
e = get_entry(table_base, v);
|
continue;
|
}
|
|
acpar.target = t->u.kernel.target;
|
acpar.targinfo = t->data;
|
|
verdict = t->u.kernel.target->target(skb, &acpar);
|
if (verdict == XT_CONTINUE)
|
e = ip6t_next_entry(e);
|
else
|
/* Verdict */
|
break;
|
} while (!acpar.hotdrop);
|
|
xt_write_recseq_end(addend);
|
local_bh_enable();
|
|
if (acpar.hotdrop)
|
return NF_DROP;
|
else return verdict;
|
}
|
|
/* 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(const struct xt_table_info *newinfo,
|
unsigned int valid_hooks, void *entry0,
|
unsigned int *offsets)
|
{
|
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 = entry0 + pos;
|
|
if (!(valid_hooks & (1 << hook)))
|
continue;
|
|
/* Set initial back pointer. */
|
e->counters.pcnt = pos;
|
|
for (;;) {
|
const struct xt_standard_target *t
|
= (void *)ip6t_get_target_c(e);
|
int visited = e->comefrom & (1 << hook);
|
|
if (e->comefrom & (1 << NF_INET_NUMHOOKS))
|
return 0;
|
|
e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS));
|
|
/* Unconditional return/END. */
|
if ((unconditional(e) &&
|
(strcmp(t->target.u.user.name,
|
XT_STANDARD_TARGET) == 0) &&
|
t->verdict < 0) || visited) {
|
unsigned int oldpos, size;
|
|
/* Return: backtrack through the last
|
big jump. */
|
do {
|
e->comefrom ^= (1<<NF_INET_NUMHOOKS);
|
oldpos = pos;
|
pos = e->counters.pcnt;
|
e->counters.pcnt = 0;
|
|
/* We're at the start. */
|
if (pos == oldpos)
|
goto next;
|
|
e = entry0 + pos;
|
} while (oldpos == pos + e->next_offset);
|
|
/* Move along one */
|
size = e->next_offset;
|
e = entry0 + pos + size;
|
if (pos + size >= newinfo->size)
|
return 0;
|
e->counters.pcnt = pos;
|
pos += size;
|
} else {
|
int newpos = t->verdict;
|
|
if (strcmp(t->target.u.user.name,
|
XT_STANDARD_TARGET) == 0 &&
|
newpos >= 0) {
|
/* This a jump; chase it. */
|
if (!xt_find_jump_offset(offsets, newpos,
|
newinfo->number))
|
return 0;
|
} else {
|
/* ... this is a fallthru */
|
newpos = pos + e->next_offset;
|
if (newpos >= newinfo->size)
|
return 0;
|
}
|
e = entry0 + newpos;
|
e->counters.pcnt = pos;
|
pos = newpos;
|
}
|
}
|
next: ;
|
}
|
return 1;
|
}
|
|
static void cleanup_match(struct xt_entry_match *m, struct net *net)
|
{
|
struct xt_mtdtor_param par;
|
|
par.net = net;
|
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);
|
}
|
|
static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
|
{
|
const struct ip6t_ip6 *ipv6 = par->entryinfo;
|
|
par->match = m->u.kernel.match;
|
par->matchinfo = m->data;
|
|
return xt_check_match(par, m->u.match_size - sizeof(*m),
|
ipv6->proto, ipv6->invflags & IP6T_INV_PROTO);
|
}
|
|
static int
|
find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
|
{
|
struct xt_match *match;
|
int ret;
|
|
match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name,
|
m->u.user.revision);
|
if (IS_ERR(match))
|
return PTR_ERR(match);
|
|
m->u.kernel.match = match;
|
|
ret = check_match(m, par);
|
if (ret)
|
goto err;
|
|
return 0;
|
err:
|
module_put(m->u.kernel.match->me);
|
return ret;
|
}
|
|
static int check_target(struct ip6t_entry *e, struct net *net, const char *name)
|
{
|
struct xt_entry_target *t = ip6t_get_target(e);
|
struct xt_tgchk_param par = {
|
.net = net,
|
.table = name,
|
.entryinfo = e,
|
.target = t->u.kernel.target,
|
.targinfo = t->data,
|
.hook_mask = e->comefrom,
|
.family = NFPROTO_IPV6,
|
};
|
|
return xt_check_target(&par, t->u.target_size - sizeof(*t),
|
e->ipv6.proto,
|
e->ipv6.invflags & IP6T_INV_PROTO);
|
}
|
|
static int
|
find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
|
unsigned int size,
|
struct xt_percpu_counter_alloc_state *alloc_state)
|
{
|
struct xt_entry_target *t;
|
struct xt_target *target;
|
int ret;
|
unsigned int j;
|
struct xt_mtchk_param mtpar;
|
struct xt_entry_match *ematch;
|
|
if (!xt_percpu_counter_alloc(alloc_state, &e->counters))
|
return -ENOMEM;
|
|
j = 0;
|
memset(&mtpar, 0, sizeof(mtpar));
|
mtpar.net = net;
|
mtpar.table = name;
|
mtpar.entryinfo = &e->ipv6;
|
mtpar.hook_mask = e->comefrom;
|
mtpar.family = NFPROTO_IPV6;
|
xt_ematch_foreach(ematch, e) {
|
ret = find_check_match(ematch, &mtpar);
|
if (ret != 0)
|
goto cleanup_matches;
|
++j;
|
}
|
|
t = ip6t_get_target(e);
|
target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name,
|
t->u.user.revision);
|
if (IS_ERR(target)) {
|
ret = PTR_ERR(target);
|
goto cleanup_matches;
|
}
|
t->u.kernel.target = target;
|
|
ret = check_target(e, net, name);
|
if (ret)
|
goto err;
|
return 0;
|
err:
|
module_put(t->u.kernel.target->me);
|
cleanup_matches:
|
xt_ematch_foreach(ematch, e) {
|
if (j-- == 0)
|
break;
|
cleanup_match(ematch, net);
|
}
|
|
xt_percpu_counter_free(&e->counters);
|
|
return ret;
|
}
|
|
static bool check_underflow(const struct ip6t_entry *e)
|
{
|
const struct xt_entry_target *t;
|
unsigned int verdict;
|
|
if (!unconditional(e))
|
return false;
|
t = ip6t_get_target_c(e);
|
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
|
return false;
|
verdict = ((struct xt_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,
|
const unsigned char *base,
|
const unsigned char *limit,
|
const unsigned int *hook_entries,
|
const unsigned int *underflows,
|
unsigned int valid_hooks)
|
{
|
unsigned int h;
|
int err;
|
|
if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 ||
|
(unsigned char *)e + sizeof(struct ip6t_entry) >= limit ||
|
(unsigned char *)e + e->next_offset > limit)
|
return -EINVAL;
|
|
if (e->next_offset
|
< sizeof(struct ip6t_entry) + sizeof(struct xt_entry_target))
|
return -EINVAL;
|
|
if (!ip6_checkentry(&e->ipv6))
|
return -EINVAL;
|
|
err = xt_check_entry_offsets(e, e->elems, e->target_offset,
|
e->next_offset);
|
if (err)
|
return err;
|
|
/* 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))
|
return -EINVAL;
|
|
newinfo->underflow[h] = underflows[h];
|
}
|
}
|
|
/* Clear counters and comefrom */
|
e->counters = ((struct xt_counters) { 0, 0 });
|
e->comefrom = 0;
|
return 0;
|
}
|
|
static void cleanup_entry(struct ip6t_entry *e, struct net *net)
|
{
|
struct xt_tgdtor_param par;
|
struct xt_entry_target *t;
|
struct xt_entry_match *ematch;
|
|
/* Cleanup all matches */
|
xt_ematch_foreach(ematch, e)
|
cleanup_match(ematch, net);
|
t = ip6t_get_target(e);
|
|
par.net = net;
|
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);
|
xt_percpu_counter_free(&e->counters);
|
}
|
|
/* Checks and translates the user-supplied table segment (held in
|
newinfo) */
|
static int
|
translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0,
|
const struct ip6t_replace *repl)
|
{
|
struct xt_percpu_counter_alloc_state alloc_state = { 0 };
|
struct ip6t_entry *iter;
|
unsigned int *offsets;
|
unsigned int i;
|
int ret = 0;
|
|
newinfo->size = repl->size;
|
newinfo->number = repl->num_entries;
|
|
/* Init all hooks to impossible value. */
|
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
|
newinfo->hook_entry[i] = 0xFFFFFFFF;
|
newinfo->underflow[i] = 0xFFFFFFFF;
|
}
|
|
offsets = xt_alloc_entry_offsets(newinfo->number);
|
if (!offsets)
|
return -ENOMEM;
|
i = 0;
|
/* Walk through entries, checking offsets. */
|
xt_entry_foreach(iter, entry0, newinfo->size) {
|
ret = check_entry_size_and_hooks(iter, newinfo, entry0,
|
entry0 + repl->size,
|
repl->hook_entry,
|
repl->underflow,
|
repl->valid_hooks);
|
if (ret != 0)
|
goto out_free;
|
if (i < repl->num_entries)
|
offsets[i] = (void *)iter - entry0;
|
++i;
|
if (strcmp(ip6t_get_target(iter)->u.user.name,
|
XT_ERROR_TARGET) == 0)
|
++newinfo->stacksize;
|
}
|
|
ret = -EINVAL;
|
if (i != repl->num_entries)
|
goto out_free;
|
|
ret = xt_check_table_hooks(newinfo, repl->valid_hooks);
|
if (ret)
|
goto out_free;
|
|
if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) {
|
ret = -ELOOP;
|
goto out_free;
|
}
|
kvfree(offsets);
|
|
/* Finally, each sanity check must pass */
|
i = 0;
|
xt_entry_foreach(iter, entry0, newinfo->size) {
|
ret = find_check_entry(iter, net, repl->name, repl->size,
|
&alloc_state);
|
if (ret != 0)
|
break;
|
++i;
|
}
|
|
if (ret != 0) {
|
xt_entry_foreach(iter, entry0, newinfo->size) {
|
if (i-- == 0)
|
break;
|
cleanup_entry(iter, net);
|
}
|
return ret;
|
}
|
|
return ret;
|
out_free:
|
kvfree(offsets);
|
return ret;
|
}
|
|
static void
|
get_counters(const struct xt_table_info *t,
|
struct xt_counters counters[])
|
{
|
struct ip6t_entry *iter;
|
unsigned int cpu;
|
unsigned int i;
|
|
for_each_possible_cpu(cpu) {
|
seqcount_t *s = &per_cpu(xt_recseq, cpu);
|
|
i = 0;
|
xt_entry_foreach(iter, t->entries, t->size) {
|
struct xt_counters *tmp;
|
u64 bcnt, pcnt;
|
unsigned int start;
|
|
tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
|
do {
|
start = read_seqcount_begin(s);
|
bcnt = tmp->bcnt;
|
pcnt = tmp->pcnt;
|
} while (read_seqcount_retry(s, start));
|
|
ADD_COUNTER(counters[i], bcnt, pcnt);
|
++i;
|
cond_resched();
|
}
|
}
|
}
|
|
static void get_old_counters(const struct xt_table_info *t,
|
struct xt_counters counters[])
|
{
|
struct ip6t_entry *iter;
|
unsigned int cpu, i;
|
|
for_each_possible_cpu(cpu) {
|
i = 0;
|
xt_entry_foreach(iter, t->entries, t->size) {
|
const struct xt_counters *tmp;
|
|
tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
|
ADD_COUNTER(counters[i], tmp->bcnt, tmp->pcnt);
|
++i;
|
}
|
cond_resched();
|
}
|
}
|
|
static struct xt_counters *alloc_counters(const struct xt_table *table)
|
{
|
unsigned int countersize;
|
struct xt_counters *counters;
|
const 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 = vzalloc(countersize);
|
|
if (counters == NULL)
|
return ERR_PTR(-ENOMEM);
|
|
get_counters(private, counters);
|
|
return counters;
|
}
|
|
static int
|
copy_entries_to_user(unsigned int total_size,
|
const struct xt_table *table,
|
void __user *userptr)
|
{
|
unsigned int off, num;
|
const 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);
|
|
loc_cpu_entry = private->entries;
|
|
/* 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 xt_entry_match *m;
|
const struct xt_entry_target *t;
|
|
e = loc_cpu_entry + off;
|
if (copy_to_user(userptr + off, e, sizeof(*e))) {
|
ret = -EFAULT;
|
goto free_counters;
|
}
|
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 (xt_match_to_user(m, userptr + off + i)) {
|
ret = -EFAULT;
|
goto free_counters;
|
}
|
}
|
|
t = ip6t_get_target_c(e);
|
if (xt_target_to_user(t, userptr + off + e->target_offset)) {
|
ret = -EFAULT;
|
goto free_counters;
|
}
|
}
|
|
free_counters:
|
vfree(counters);
|
return ret;
|
}
|
|
#ifdef CONFIG_COMPAT
|
static void compat_standard_from_user(void *dst, const 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, const 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 int compat_calc_entry(const struct ip6t_entry *e,
|
const struct xt_table_info *info,
|
const void *base, struct xt_table_info *newinfo)
|
{
|
const struct xt_entry_match *ematch;
|
const struct xt_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;
|
xt_ematch_foreach(ematch, e)
|
off += xt_compat_match_offset(ematch->u.kernel.match);
|
t = ip6t_get_target_c(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)
|
{
|
struct ip6t_entry *iter;
|
const void *loc_cpu_entry;
|
int ret;
|
|
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;
|
ret = xt_compat_init_offsets(AF_INET6, info->number);
|
if (ret)
|
return ret;
|
xt_entry_foreach(iter, loc_cpu_entry, info->size) {
|
ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
|
if (ret != 0)
|
return ret;
|
}
|
return 0;
|
}
|
#endif
|
|
static int get_info(struct net *net, void __user *user, const int *len)
|
{
|
char name[XT_TABLE_MAXNAMELEN];
|
struct xt_table *t;
|
int ret;
|
|
if (*len != sizeof(struct ip6t_getinfo))
|
return -EINVAL;
|
|
if (copy_from_user(name, user, sizeof(name)) != 0)
|
return -EFAULT;
|
|
name[XT_TABLE_MAXNAMELEN-1] = '\0';
|
#ifdef CONFIG_COMPAT
|
if (in_compat_syscall())
|
xt_compat_lock(AF_INET6);
|
#endif
|
t = xt_request_find_table_lock(net, AF_INET6, name);
|
if (!IS_ERR(t)) {
|
struct ip6t_getinfo info;
|
const struct xt_table_info *private = t->private;
|
#ifdef CONFIG_COMPAT
|
struct xt_table_info tmp;
|
|
if (in_compat_syscall()) {
|
ret = compat_table_info(private, &tmp);
|
xt_compat_flush_offsets(AF_INET6);
|
private = &tmp;
|
}
|
#endif
|
memset(&info, 0, sizeof(info));
|
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 = PTR_ERR(t);
|
#ifdef CONFIG_COMPAT
|
if (in_compat_syscall())
|
xt_compat_unlock(AF_INET6);
|
#endif
|
return ret;
|
}
|
|
static int
|
get_entries(struct net *net, struct ip6t_get_entries __user *uptr,
|
const int *len)
|
{
|
int ret;
|
struct ip6t_get_entries get;
|
struct xt_table *t;
|
|
if (*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)
|
return -EINVAL;
|
|
get.name[sizeof(get.name) - 1] = '\0';
|
|
t = xt_find_table_lock(net, AF_INET6, get.name);
|
if (!IS_ERR(t)) {
|
struct xt_table_info *private = t->private;
|
if (get.size == private->size)
|
ret = copy_entries_to_user(private->size,
|
t, uptr->entrytable);
|
else
|
ret = -EAGAIN;
|
|
module_put(t->me);
|
xt_table_unlock(t);
|
} else
|
ret = PTR_ERR(t);
|
|
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;
|
struct ip6t_entry *iter;
|
|
ret = 0;
|
counters = xt_counters_alloc(num_counters);
|
if (!counters) {
|
ret = -ENOMEM;
|
goto out;
|
}
|
|
t = xt_request_find_table_lock(net, AF_INET6, name);
|
if (IS_ERR(t)) {
|
ret = PTR_ERR(t);
|
goto free_newinfo_counters_untrans;
|
}
|
|
/* You lied! */
|
if (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 */
|
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);
|
|
xt_table_unlock(t);
|
|
get_old_counters(oldinfo, counters);
|
|
/* Decrease module usage counts and free resource */
|
xt_entry_foreach(iter, oldinfo->entries, oldinfo->size)
|
cleanup_entry(iter, net);
|
|
xt_free_table_info(oldinfo);
|
if (copy_to_user(counters_ptr, counters,
|
sizeof(struct xt_counters) * num_counters) != 0) {
|
/* Silent error, can't fail, new table is already in place */
|
net_warn_ratelimited("ip6tables: counters copy to user failed while replacing table\n");
|
}
|
vfree(counters);
|
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, sockptr_t arg, unsigned int len)
|
{
|
int ret;
|
struct ip6t_replace tmp;
|
struct xt_table_info *newinfo;
|
void *loc_cpu_entry;
|
struct ip6t_entry *iter;
|
|
if (copy_from_sockptr(&tmp, arg, sizeof(tmp)) != 0)
|
return -EFAULT;
|
|
/* overflow check */
|
if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
|
return -ENOMEM;
|
if (tmp.num_counters == 0)
|
return -EINVAL;
|
|
tmp.name[sizeof(tmp.name)-1] = 0;
|
|
newinfo = xt_alloc_table_info(tmp.size);
|
if (!newinfo)
|
return -ENOMEM;
|
|
loc_cpu_entry = newinfo->entries;
|
if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
|
tmp.size) != 0) {
|
ret = -EFAULT;
|
goto free_newinfo;
|
}
|
|
ret = translate_table(net, newinfo, loc_cpu_entry, &tmp);
|
if (ret != 0)
|
goto free_newinfo;
|
|
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:
|
xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
|
cleanup_entry(iter, net);
|
free_newinfo:
|
xt_free_table_info(newinfo);
|
return ret;
|
}
|
|
static int
|
do_add_counters(struct net *net, sockptr_t arg, unsigned int len)
|
{
|
unsigned int i;
|
struct xt_counters_info tmp;
|
struct xt_counters *paddc;
|
struct xt_table *t;
|
const struct xt_table_info *private;
|
int ret = 0;
|
struct ip6t_entry *iter;
|
unsigned int addend;
|
|
paddc = xt_copy_counters(arg, len, &tmp);
|
if (IS_ERR(paddc))
|
return PTR_ERR(paddc);
|
t = xt_find_table_lock(net, AF_INET6, tmp.name);
|
if (IS_ERR(t)) {
|
ret = PTR_ERR(t);
|
goto free;
|
}
|
|
local_bh_disable();
|
private = t->private;
|
if (private->number != tmp.num_counters) {
|
ret = -EINVAL;
|
goto unlock_up_free;
|
}
|
|
i = 0;
|
addend = xt_write_recseq_begin();
|
xt_entry_foreach(iter, private->entries, private->size) {
|
struct xt_counters *tmp;
|
|
tmp = xt_get_this_cpu_counter(&iter->counters);
|
ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
|
++i;
|
}
|
xt_write_recseq_end(addend);
|
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[XT_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 xt_counters * */
|
struct compat_ip6t_entry entries[];
|
};
|
|
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 xt_entry_target *t;
|
struct compat_ip6t_entry __user *ce;
|
u_int16_t target_offset, next_offset;
|
compat_uint_t origsize;
|
const struct xt_entry_match *ematch;
|
int ret = 0;
|
|
origsize = *size;
|
ce = *dstptr;
|
if (copy_to_user(ce, e, sizeof(struct ip6t_entry)) != 0 ||
|
copy_to_user(&ce->counters, &counters[i],
|
sizeof(counters[i])) != 0)
|
return -EFAULT;
|
|
*dstptr += sizeof(struct compat_ip6t_entry);
|
*size -= sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
|
|
xt_ematch_foreach(ematch, e) {
|
ret = xt_compat_match_to_user(ematch, dstptr, size);
|
if (ret != 0)
|
return ret;
|
}
|
target_offset = e->target_offset - (origsize - *size);
|
t = ip6t_get_target(e);
|
ret = xt_compat_target_to_user(t, dstptr, size);
|
if (ret)
|
return ret;
|
next_offset = e->next_offset - (origsize - *size);
|
if (put_user(target_offset, &ce->target_offset) != 0 ||
|
put_user(next_offset, &ce->next_offset) != 0)
|
return -EFAULT;
|
return 0;
|
}
|
|
static int
|
compat_find_calc_match(struct xt_entry_match *m,
|
const struct ip6t_ip6 *ipv6,
|
int *size)
|
{
|
struct xt_match *match;
|
|
match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name,
|
m->u.user.revision);
|
if (IS_ERR(match))
|
return PTR_ERR(match);
|
|
m->u.kernel.match = match;
|
*size += xt_compat_match_offset(match);
|
return 0;
|
}
|
|
static void compat_release_entry(struct compat_ip6t_entry *e)
|
{
|
struct xt_entry_target *t;
|
struct xt_entry_match *ematch;
|
|
/* Cleanup all matches */
|
xt_ematch_foreach(ematch, e)
|
module_put(ematch->u.kernel.match->me);
|
t = compat_ip6t_get_target(e);
|
module_put(t->u.kernel.target->me);
|
}
|
|
static int
|
check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
|
struct xt_table_info *newinfo,
|
unsigned int *size,
|
const unsigned char *base,
|
const unsigned char *limit)
|
{
|
struct xt_entry_match *ematch;
|
struct xt_entry_target *t;
|
struct xt_target *target;
|
unsigned int entry_offset;
|
unsigned int j;
|
int ret, off;
|
|
if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 ||
|
(unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit ||
|
(unsigned char *)e + e->next_offset > limit)
|
return -EINVAL;
|
|
if (e->next_offset < sizeof(struct compat_ip6t_entry) +
|
sizeof(struct compat_xt_entry_target))
|
return -EINVAL;
|
|
if (!ip6_checkentry(&e->ipv6))
|
return -EINVAL;
|
|
ret = xt_compat_check_entry_offsets(e, e->elems,
|
e->target_offset, e->next_offset);
|
if (ret)
|
return ret;
|
|
off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
|
entry_offset = (void *)e - (void *)base;
|
j = 0;
|
xt_ematch_foreach(ematch, e) {
|
ret = compat_find_calc_match(ematch, &e->ipv6, &off);
|
if (ret != 0)
|
goto release_matches;
|
++j;
|
}
|
|
t = compat_ip6t_get_target(e);
|
target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name,
|
t->u.user.revision);
|
if (IS_ERR(target)) {
|
ret = PTR_ERR(target);
|
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;
|
|
return 0;
|
|
out:
|
module_put(t->u.kernel.target->me);
|
release_matches:
|
xt_ematch_foreach(ematch, e) {
|
if (j-- == 0)
|
break;
|
module_put(ematch->u.kernel.match->me);
|
}
|
return ret;
|
}
|
|
static void
|
compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
|
unsigned int *size,
|
struct xt_table_info *newinfo, unsigned char *base)
|
{
|
struct xt_entry_target *t;
|
struct ip6t_entry *de;
|
unsigned int origsize;
|
int h;
|
struct xt_entry_match *ematch;
|
|
origsize = *size;
|
de = *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);
|
|
xt_ematch_foreach(ematch, e)
|
xt_compat_match_from_user(ematch, dstptr, size);
|
|
de->target_offset = e->target_offset - (origsize - *size);
|
t = compat_ip6t_get_target(e);
|
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;
|
}
|
}
|
|
static int
|
translate_compat_table(struct net *net,
|
struct xt_table_info **pinfo,
|
void **pentry0,
|
const struct compat_ip6t_replace *compatr)
|
{
|
unsigned int i, j;
|
struct xt_table_info *newinfo, *info;
|
void *pos, *entry0, *entry1;
|
struct compat_ip6t_entry *iter0;
|
struct ip6t_replace repl;
|
unsigned int size;
|
int ret;
|
|
info = *pinfo;
|
entry0 = *pentry0;
|
size = compatr->size;
|
info->number = compatr->num_entries;
|
|
j = 0;
|
xt_compat_lock(AF_INET6);
|
ret = xt_compat_init_offsets(AF_INET6, compatr->num_entries);
|
if (ret)
|
goto out_unlock;
|
/* Walk through entries, checking offsets. */
|
xt_entry_foreach(iter0, entry0, compatr->size) {
|
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
|
entry0,
|
entry0 + compatr->size);
|
if (ret != 0)
|
goto out_unlock;
|
++j;
|
}
|
|
ret = -EINVAL;
|
if (j != compatr->num_entries)
|
goto out_unlock;
|
|
ret = -ENOMEM;
|
newinfo = xt_alloc_table_info(size);
|
if (!newinfo)
|
goto out_unlock;
|
|
memset(newinfo->entries, 0, size);
|
|
newinfo->number = compatr->num_entries;
|
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
|
newinfo->hook_entry[i] = compatr->hook_entry[i];
|
newinfo->underflow[i] = compatr->underflow[i];
|
}
|
entry1 = newinfo->entries;
|
pos = entry1;
|
size = compatr->size;
|
xt_entry_foreach(iter0, entry0, compatr->size)
|
compat_copy_entry_from_user(iter0, &pos, &size,
|
newinfo, entry1);
|
|
/* all module references in entry0 are now gone. */
|
xt_compat_flush_offsets(AF_INET6);
|
xt_compat_unlock(AF_INET6);
|
|
memcpy(&repl, compatr, sizeof(*compatr));
|
|
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
|
repl.hook_entry[i] = newinfo->hook_entry[i];
|
repl.underflow[i] = newinfo->underflow[i];
|
}
|
|
repl.num_counters = 0;
|
repl.counters = NULL;
|
repl.size = newinfo->size;
|
ret = translate_table(net, newinfo, entry1, &repl);
|
if (ret)
|
goto free_newinfo;
|
|
*pinfo = newinfo;
|
*pentry0 = entry1;
|
xt_free_table_info(info);
|
return 0;
|
|
free_newinfo:
|
xt_free_table_info(newinfo);
|
return ret;
|
out_unlock:
|
xt_compat_flush_offsets(AF_INET6);
|
xt_compat_unlock(AF_INET6);
|
xt_entry_foreach(iter0, entry0, compatr->size) {
|
if (j-- == 0)
|
break;
|
compat_release_entry(iter0);
|
}
|
return ret;
|
}
|
|
static int
|
compat_do_replace(struct net *net, sockptr_t arg, unsigned int len)
|
{
|
int ret;
|
struct compat_ip6t_replace tmp;
|
struct xt_table_info *newinfo;
|
void *loc_cpu_entry;
|
struct ip6t_entry *iter;
|
|
if (copy_from_sockptr(&tmp, arg, sizeof(tmp)) != 0)
|
return -EFAULT;
|
|
/* overflow check */
|
if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
|
return -ENOMEM;
|
if (tmp.num_counters == 0)
|
return -EINVAL;
|
|
tmp.name[sizeof(tmp.name)-1] = 0;
|
|
newinfo = xt_alloc_table_info(tmp.size);
|
if (!newinfo)
|
return -ENOMEM;
|
|
loc_cpu_entry = newinfo->entries;
|
if (copy_from_sockptr_offset(loc_cpu_entry, arg, sizeof(tmp),
|
tmp.size) != 0) {
|
ret = -EFAULT;
|
goto free_newinfo;
|
}
|
|
ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
|
if (ret != 0)
|
goto free_newinfo;
|
|
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:
|
xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
|
cleanup_entry(iter, net);
|
free_newinfo:
|
xt_free_table_info(newinfo);
|
return ret;
|
}
|
|
struct compat_ip6t_get_entries {
|
char name[XT_TABLE_MAXNAMELEN];
|
compat_uint_t size;
|
struct compat_ip6t_entry entrytable[];
|
};
|
|
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;
|
unsigned int i = 0;
|
struct ip6t_entry *iter;
|
|
counters = alloc_counters(table);
|
if (IS_ERR(counters))
|
return PTR_ERR(counters);
|
|
pos = userptr;
|
size = total_size;
|
xt_entry_foreach(iter, private->entries, total_size) {
|
ret = compat_copy_entry_to_user(iter, &pos,
|
&size, counters, i++);
|
if (ret != 0)
|
break;
|
}
|
|
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))
|
return -EINVAL;
|
|
if (copy_from_user(&get, uptr, sizeof(get)) != 0)
|
return -EFAULT;
|
|
if (*len != sizeof(struct compat_ip6t_get_entries) + get.size)
|
return -EINVAL;
|
|
get.name[sizeof(get.name) - 1] = '\0';
|
|
xt_compat_lock(AF_INET6);
|
t = xt_find_table_lock(net, AF_INET6, get.name);
|
if (!IS_ERR(t)) {
|
const struct xt_table_info *private = t->private;
|
struct xt_table_info info;
|
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)
|
ret = -EAGAIN;
|
|
xt_compat_flush_offsets(AF_INET6);
|
module_put(t->me);
|
xt_table_unlock(t);
|
} else
|
ret = PTR_ERR(t);
|
|
xt_compat_unlock(AF_INET6);
|
return ret;
|
}
|
#endif
|
|
static int
|
do_ip6t_set_ctl(struct sock *sk, int cmd, sockptr_t arg, unsigned int len)
|
{
|
int ret;
|
|
if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
|
return -EPERM;
|
|
switch (cmd) {
|
case IP6T_SO_SET_REPLACE:
|
#ifdef CONFIG_COMPAT
|
if (in_compat_syscall())
|
ret = compat_do_replace(sock_net(sk), arg, len);
|
else
|
#endif
|
ret = do_replace(sock_net(sk), arg, len);
|
break;
|
|
case IP6T_SO_SET_ADD_COUNTERS:
|
ret = do_add_counters(sock_net(sk), arg, len);
|
break;
|
|
default:
|
ret = -EINVAL;
|
}
|
|
return ret;
|
}
|
|
static int
|
do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
|
{
|
int ret;
|
|
if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
|
return -EPERM;
|
|
switch (cmd) {
|
case IP6T_SO_GET_INFO:
|
ret = get_info(sock_net(sk), user, len);
|
break;
|
|
case IP6T_SO_GET_ENTRIES:
|
#ifdef CONFIG_COMPAT
|
if (in_compat_syscall())
|
ret = compat_get_entries(sock_net(sk), user, len);
|
else
|
#endif
|
ret = get_entries(sock_net(sk), user, len);
|
break;
|
|
case IP6T_SO_GET_REVISION_MATCH:
|
case IP6T_SO_GET_REVISION_TARGET: {
|
struct xt_get_revision rev;
|
int target;
|
|
if (*len != sizeof(rev)) {
|
ret = -EINVAL;
|
break;
|
}
|
if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
|
ret = -EFAULT;
|
break;
|
}
|
rev.name[sizeof(rev.name)-1] = 0;
|
|
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:
|
ret = -EINVAL;
|
}
|
|
return ret;
|
}
|
|
static void __ip6t_unregister_table(struct net *net, struct xt_table *table)
|
{
|
struct xt_table_info *private;
|
void *loc_cpu_entry;
|
struct module *table_owner = table->me;
|
struct ip6t_entry *iter;
|
|
private = xt_unregister_table(table);
|
|
/* Decrease module usage counts and free resources */
|
loc_cpu_entry = private->entries;
|
xt_entry_foreach(iter, loc_cpu_entry, private->size)
|
cleanup_entry(iter, net);
|
if (private->number > private->initial_entries)
|
module_put(table_owner);
|
xt_free_table_info(private);
|
}
|
|
int ip6t_register_table(struct net *net, const struct xt_table *table,
|
const struct ip6t_replace *repl,
|
const struct nf_hook_ops *ops,
|
struct xt_table **res)
|
{
|
int ret;
|
struct xt_table_info *newinfo;
|
struct xt_table_info bootstrap = {0};
|
void *loc_cpu_entry;
|
struct xt_table *new_table;
|
|
newinfo = xt_alloc_table_info(repl->size);
|
if (!newinfo)
|
return -ENOMEM;
|
|
loc_cpu_entry = newinfo->entries;
|
memcpy(loc_cpu_entry, repl->entries, repl->size);
|
|
ret = translate_table(net, newinfo, loc_cpu_entry, repl);
|
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;
|
}
|
|
/* set res now, will see skbs right after nf_register_net_hooks */
|
WRITE_ONCE(*res, new_table);
|
if (!ops)
|
return 0;
|
|
ret = nf_register_net_hooks(net, ops, hweight32(table->valid_hooks));
|
if (ret != 0) {
|
__ip6t_unregister_table(net, new_table);
|
*res = NULL;
|
}
|
|
return ret;
|
|
out_free:
|
xt_free_table_info(newinfo);
|
return ret;
|
}
|
|
void ip6t_unregister_table_pre_exit(struct net *net, struct xt_table *table,
|
const struct nf_hook_ops *ops)
|
{
|
nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
|
}
|
|
void ip6t_unregister_table_exit(struct net *net, struct xt_table *table)
|
{
|
__ip6t_unregister_table(net, table);
|
}
|
|
void ip6t_unregister_table(struct net *net, struct xt_table *table,
|
const struct nf_hook_ops *ops)
|
{
|
if (ops)
|
ip6t_unregister_table_pre_exit(net, table, ops);
|
__ip6t_unregister_table(net, table);
|
}
|
|
/* 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, struct xt_action_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.
|
*/
|
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 int 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) ? -EINVAL : 0;
|
}
|
|
/* The built-in targets: standard (NULL) and error. */
|
static struct xt_target ip6t_builtin_tg[] __read_mostly = {
|
{
|
.name = XT_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
|
},
|
{
|
.name = XT_ERROR_TARGET,
|
.target = ip6t_error,
|
.targetsize = XT_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,
|
.get_optmin = IP6T_BASE_CTL,
|
.get_optmax = IP6T_SO_GET_MAX+1,
|
.get = do_ip6t_get_ctl,
|
.owner = THIS_MODULE,
|
};
|
|
static struct xt_match ip6t_builtin_mt[] __read_mostly = {
|
{
|
.name = "icmp6",
|
.match = icmp6_match,
|
.matchsize = sizeof(struct ip6t_icmp),
|
.checkentry = icmp6_checkentry,
|
.proto = IPPROTO_ICMPV6,
|
.family = NFPROTO_IPV6,
|
.me = THIS_MODULE,
|
},
|
};
|
|
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;
|
|
/* No one else will be downing sem now, so we won't sleep */
|
ret = xt_register_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
|
if (ret < 0)
|
goto err2;
|
ret = xt_register_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt));
|
if (ret < 0)
|
goto err4;
|
|
/* Register setsockopt */
|
ret = nf_register_sockopt(&ip6t_sockopts);
|
if (ret < 0)
|
goto err5;
|
|
return 0;
|
|
err5:
|
xt_unregister_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt));
|
err4:
|
xt_unregister_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
|
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_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt));
|
xt_unregister_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
|
unregister_pernet_subsys(&ip6_tables_net_ops);
|
}
|
|
EXPORT_SYMBOL(ip6t_register_table);
|
EXPORT_SYMBOL(ip6t_unregister_table);
|
EXPORT_SYMBOL(ip6t_unregister_table_pre_exit);
|
EXPORT_SYMBOL(ip6t_unregister_table_exit);
|
EXPORT_SYMBOL(ip6t_do_table);
|
|
module_init(ip6_tables_init);
|
module_exit(ip6_tables_fini);
|
