* 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>
#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)) {
+ &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,
/* All zeroes == unconditional rule. */
/* Mildly perf critical (only if packet tracing is on) */
-static inline int
-unconditional(const struct ip6t_ip6 *ipv6)
+static inline bool unconditional(const struct ip6t_ip6 *ipv6)
{
- unsigned int i;
+ static const struct ip6t_ip6 uncond;
- for (i = 0; i < sizeof(*ipv6); i++)
- if (((char *)ipv6)[i])
- break;
-
- return (i == sizeof(*ipv6));
+ return memcmp(ipv6, &uncond, sizeof(uncond)) == 0;
}
#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
} 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)) {
+ 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]
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. */
mtpar.in = tgpar.in = in;
mtpar.out = tgpar.out = out;
mtpar.family = tgpar.family = NFPROTO_IPV6;
- tgpar.hooknum = hook;
+ mtpar.hooknum = tgpar.hooknum = hook;
IP_NF_ASSERT(table->valid_hooks & (1 << hook));
back = get_entry(table_base, back->comefrom);
continue;
}
- if (table_base + v != ip6t_next_entry(e)
- && !(e->ipv6.flags & IP6T_F_GOTO)) {
+ 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;
tgpar.targinfo = t->data;
#ifdef CONFIG_NETFILTER_DEBUG
- ((struct ip6t_entry *)table_base)->comefrom = 0xeeeeeeec;
+ tb_comefrom = 0xeeeeeeec;
#endif
verdict = t->u.kernel.target->target(skb, &tgpar);
#ifdef CONFIG_NETFILTER_DEBUG
- if (((struct ip6t_entry *)table_base)->comefrom != 0xeeeeeeec &&
- verdict == IP6T_CONTINUE) {
+ if (tb_comefrom != 0xeeeeeeec && verdict == IP6T_CONTINUE) {
printk("Target %s reentered!\n",
t->u.kernel.target->name);
verdict = NF_DROP;
}
- ((struct ip6t_entry *)table_base)->comefrom = 0x57acc001;
+ tb_comefrom = 0x57acc001;
#endif
if (verdict == IP6T_CONTINUE)
e = ip6t_next_entry(e);
} while (!hotdrop);
#ifdef CONFIG_NETFILTER_DEBUG
- ((struct ip6t_entry *)table_base)->comefrom = NETFILTER_LINK_POISON;
+ tb_comefrom = NETFILTER_LINK_POISON;
#endif
xt_info_rdunlock_bh();
return NF_DROP;
else return verdict;
#endif
+
+#undef tb_comefrom
}
/* Figures out from what hook each rule can be called: returns 0 if
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) {
+ 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,
int newpos = t->verdict;
if (strcmp(t->target.u.user.name,
- IP6T_STANDARD_TARGET) == 0
- && newpos >= 0) {
+ IP6T_STANDARD_TARGET) == 0 &&
+ newpos >= 0) {
if (newpos > newinfo->size -
sizeof(struct ip6t_entry)) {
duprintf("mark_source_chains: "
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 *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) {
+ 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;
}
/* 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 ((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];
+ }
}
- /* FIXME: underflows must be unconditional, standard verdicts
- < 0 (not IP6T_RETURN). --RR */
-
/* Clear counters and comefrom */
e->counters = ((struct xt_counters) { 0, 0 });
e->comefrom = 0;
newinfo,
entry0,
entry0 + size,
- hook_entries, underflows, &i);
+ hook_entries, underflows, valid_hooks, &i);
if (ret != 0)
return ret;
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) {
- struct xt_table_info tmp;
ret = compat_table_info(private, &tmp);
xt_compat_flush_offsets(AF_INET6);
private = &tmp;
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) {
+ 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;
}
return ret;
}
-struct xt_table *ip6t_register_table(struct net *net, struct xt_table *table,
+struct xt_table *ip6t_register_table(struct net *net,
+ const struct xt_table *table,
const struct ip6t_replace *repl)
{
int ret;