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authorBart De Schuymer <bdschuym@pandora.be>2002-08-23 19:57:34 +0000
committerBart De Schuymer <bdschuym@pandora.be>2002-08-23 19:57:34 +0000
commitbfa68d6b7c8799e4566bd2b85a54610435fe94bc (patch)
tree3878a2e53b1a3d0d7b81e28726601633314401f5 /kernel/linux2.5/net/bridge/netfilter
parent7dd8dbee70f4824d874838160655c248ae124f6c (diff)
*** empty log message ***
Diffstat (limited to 'kernel/linux2.5/net/bridge/netfilter')
-rw-r--r--kernel/linux2.5/net/bridge/netfilter/Makefile20
-rw-r--r--kernel/linux2.5/net/bridge/netfilter/ebtables.c1484
2 files changed, 1504 insertions, 0 deletions
diff --git a/kernel/linux2.5/net/bridge/netfilter/Makefile b/kernel/linux2.5/net/bridge/netfilter/Makefile
new file mode 100644
index 0000000..a6e4bec
--- /dev/null
+++ b/kernel/linux2.5/net/bridge/netfilter/Makefile
@@ -0,0 +1,20 @@
+#
+# Makefile for the netfilter modules for Link Layer filtering on a bridge.
+#
+
+export-objs := ebtables.o
+
+obj-$(CONFIG_BRIDGE_EBT) += ebtables.o
+obj-$(CONFIG_BRIDGE_EBT_T_FILTER) += ebtable_filter.o
+obj-$(CONFIG_BRIDGE_EBT_T_NAT) += ebtable_nat.o
+obj-$(CONFIG_BRIDGE_EBT_BROUTE) += ebtable_broute.o
+obj-$(CONFIG_BRIDGE_EBT_IPF) += ebt_ip.o
+obj-$(CONFIG_BRIDGE_EBT_ARPF) += ebt_arp.o
+obj-$(CONFIG_BRIDGE_EBT_VLANF) += ebt_vlan.o
+obj-$(CONFIG_BRIDGE_EBT_MARKF) += ebt_mark_m.o
+obj-$(CONFIG_BRIDGE_EBT_LOG) += ebt_log.o
+obj-$(CONFIG_BRIDGE_EBT_SNAT) += ebt_snat.o
+obj-$(CONFIG_BRIDGE_EBT_DNAT) += ebt_dnat.o
+obj-$(CONFIG_BRIDGE_EBT_REDIRECT) += ebt_redirect.o
+obj-$(CONFIG_BRIDGE_EBT_MARK_T) += ebt_mark.o
+include $(TOPDIR)/Rules.make
diff --git a/kernel/linux2.5/net/bridge/netfilter/ebtables.c b/kernel/linux2.5/net/bridge/netfilter/ebtables.c
new file mode 100644
index 0000000..ab9e4c5
--- /dev/null
+++ b/kernel/linux2.5/net/bridge/netfilter/ebtables.c
@@ -0,0 +1,1484 @@
+/*
+ * ebtables
+ *
+ * Author:
+ * Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ * ebtables.c,v 2.0, July, 2002
+ *
+ * This code is stongly inspired on the iptables code which is
+ * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+// used for print_string
+#include <linux/sched.h>
+#include <linux/tty.h>
+
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/spinlock.h>
+#include <asm/uaccess.h>
+#include <linux/smp.h>
+#include <net/sock.h>
+// needed for logical [in,out]-dev filtering
+#include "../br_private.h"
+
+// list_named_find
+#define ASSERT_READ_LOCK(x)
+#define ASSERT_WRITE_LOCK(x)
+#include <linux/netfilter_ipv4/listhelp.h>
+
+#if 0 // use this for remote debugging
+// Copyright (C) 1998 by Ori Pomerantz
+// Print the string to the appropriate tty, the one
+// the current task uses
+static void print_string(char *str)
+{
+ struct tty_struct *my_tty;
+
+ /* The tty for the current task */
+ my_tty = current->tty;
+ if (my_tty != NULL) {
+ (*(my_tty->driver).write)(my_tty, 0, str, strlen(str));
+ (*(my_tty->driver).write)(my_tty, 0, "\015\012", 2);
+ }
+}
+
+#define BUGPRINT(args) print_string(args);
+#else
+#define BUGPRINT(format, args...) printk("kernel msg: ebtables bug: please "\
+ "report to author: "format, ## args)
+// #define BUGPRINT(format, args...)
+#endif
+#define MEMPRINT(format, args...) printk("kernel msg: ebtables "\
+ ": out of memory: "format, ## args)
+// #define MEMPRINT(format, args...)
+
+
+
+// Each cpu has its own set of counters, so there is no need for write_lock in
+// the softirq
+// For reading or updating the counters, the user context needs to
+// get a write_lock
+
+// The size of each set of counters is altered to get cache alignment
+#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
+#define COUNTER_OFFSET(n) (SMP_ALIGN(n * sizeof(struct ebt_counter)))
+#define COUNTER_BASE(c, n, cpu) ((struct ebt_counter *)(((char *)c) + \
+ COUNTER_OFFSET(n) * cpu))
+
+
+
+static DECLARE_MUTEX(ebt_mutex);
+static LIST_HEAD(ebt_tables);
+static LIST_HEAD(ebt_targets);
+static LIST_HEAD(ebt_matches);
+static LIST_HEAD(ebt_watchers);
+
+static struct ebt_target ebt_standard_target =
+{ {NULL, NULL}, EBT_STANDARD_TARGET, NULL, NULL, NULL, NULL};
+
+static inline int ebt_do_watcher (struct ebt_entry_watcher *w,
+ const struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out)
+{
+ w->u.watcher->watcher(skb, in, out, w->data,
+ w->watcher_size);
+ // watchers don't give a verdict
+ return 0;
+}
+
+static inline int ebt_do_match (struct ebt_entry_match *m,
+ const struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out)
+{
+ return m->u.match->match(skb, in, out, m->data,
+ m->match_size);
+}
+
+static inline int ebt_dev_check(char *entry, const struct net_device *device)
+{
+ if (*entry == '\0')
+ return 0;
+ if (!device)
+ return 1;
+ return !!strcmp(entry, device->name);
+}
+
+#define FWINV2(bool,invflg) ((bool) ^ !!(e->invflags & invflg))
+// process standard matches
+static inline int ebt_basic_match(struct ebt_entry *e, struct ethhdr *h,
+ const struct net_device *in, const struct net_device *out)
+{
+ int verdict, i;
+
+ if (e->bitmask & EBT_802_3) {
+ if (FWINV2(ntohs(h->h_proto) >= 1536, EBT_IPROTO))
+ return 1;
+ } else if (!(e->bitmask & EBT_NOPROTO) &&
+ FWINV2(e->ethproto != h->h_proto, EBT_IPROTO))
+ return 1;
+
+ if (FWINV2(ebt_dev_check(e->in, in), EBT_IIN))
+ return 1;
+ if (FWINV2(ebt_dev_check(e->out, out), EBT_IOUT))
+ return 1;
+ if ((!in || !in->br_port) ? 0 : FWINV2(ebt_dev_check(
+ e->logical_in, &in->br_port->br->dev), EBT_ILOGICALIN))
+ return 1;
+ if ((!out || !out->br_port) ? 0 : FWINV2(ebt_dev_check(
+ e->logical_out, &out->br_port->br->dev), EBT_ILOGICALOUT))
+ return 1;
+
+ if (e->bitmask & EBT_SOURCEMAC) {
+ verdict = 0;
+ for (i = 0; i < 6; i++)
+ verdict |= (h->h_source[i] ^ e->sourcemac[i]) &
+ e->sourcemsk[i];
+ if (FWINV2(verdict != 0, EBT_ISOURCE) )
+ return 1;
+ }
+ if (e->bitmask & EBT_DESTMAC) {
+ verdict = 0;
+ for (i = 0; i < 6; i++)
+ verdict |= (h->h_dest[i] ^ e->destmac[i]) &
+ e->destmsk[i];
+ if (FWINV2(verdict != 0, EBT_IDEST) )
+ return 1;
+ }
+ return 0;
+}
+
+// Do some firewalling
+unsigned int ebt_do_table (unsigned int hook, struct sk_buff **pskb,
+ const struct net_device *in, const struct net_device *out,
+ struct ebt_table *table)
+{
+ int i, nentries;
+ struct ebt_entry *point;
+ struct ebt_counter *counter_base, *cb_base;
+ struct ebt_entry_target *t;
+ int verdict, sp = 0;
+ struct ebt_chainstack *cs;
+ struct ebt_entries *chaininfo;
+ char *base;
+ struct ebt_table_info *private = table->private;
+
+ read_lock_bh(&table->lock);
+ cb_base = COUNTER_BASE(private->counters, private->nentries,
+ smp_processor_id());
+ if (private->chainstack)
+ cs = private->chainstack[smp_processor_id()];
+ else
+ cs = NULL;
+ chaininfo = private->hook_entry[hook];
+ nentries = private->hook_entry[hook]->nentries;
+ point = (struct ebt_entry *)(private->hook_entry[hook]->data);
+ counter_base = cb_base + private->hook_entry[hook]->counter_offset;
+ // base for chain jumps
+ base = (char *)chaininfo;
+ i = 0;
+ while (i < nentries) {
+ if (ebt_basic_match(point, (**pskb).mac.ethernet, in, out))
+ goto letscontinue;
+
+ if (EBT_MATCH_ITERATE(point, ebt_do_match, *pskb, in, out) != 0)
+ goto letscontinue;
+
+ // increase counter
+ (*(counter_base + i)).pcnt++;
+
+ // these should only watch: not modify, nor tell us
+ // what to do with the packet
+ EBT_WATCHER_ITERATE(point, ebt_do_watcher, *pskb, in,
+ out);
+
+ t = (struct ebt_entry_target *)
+ (((char *)point) + point->target_offset);
+ // standard target
+ if (!t->u.target->target)
+ verdict = ((struct ebt_standard_target *)t)->verdict;
+ else
+ verdict = t->u.target->target(pskb, hook,
+ in, out, t->data, t->target_size);
+ if (verdict == EBT_ACCEPT) {
+ read_unlock_bh(&table->lock);
+ return NF_ACCEPT;
+ }
+ if (verdict == EBT_DROP) {
+ read_unlock_bh(&table->lock);
+ return NF_DROP;
+ }
+ if (verdict == EBT_RETURN) {
+letsreturn:
+#ifdef CONFIG_NETFILTER_DEBUG
+ if (sp == 0) {
+ BUGPRINT("RETURN on base chain");
+ // act like this is EBT_CONTINUE
+ goto letscontinue;
+ }
+#endif
+ sp--;
+ // put all the local variables right
+ i = cs[sp].n;
+ chaininfo = cs[sp].chaininfo;
+ nentries = chaininfo->nentries;
+ point = cs[sp].e;
+ counter_base = cb_base +
+ chaininfo->counter_offset;
+ continue;
+ }
+ if (verdict == EBT_CONTINUE)
+ goto letscontinue;
+#ifdef CONFIG_NETFILTER_DEBUG
+ if (verdict < 0) {
+ BUGPRINT("bogus standard verdict\n");
+ read_unlock_bh(&table->lock);
+ return NF_DROP;
+ }
+#endif
+ // jump to a udc
+ cs[sp].n = i + 1;
+ cs[sp].chaininfo = chaininfo;
+ cs[sp].e = (struct ebt_entry *)
+ (((char *)point) + point->next_offset);
+ i = 0;
+ chaininfo = (struct ebt_entries *) (base + verdict);
+#ifdef CONFIG_NETFILTER_DEBUG
+ if (chaininfo->distinguisher) {
+ BUGPRINT("jump to non-chain\n");
+ read_unlock_bh(&table->lock);
+ return NF_DROP;
+ }
+#endif
+ nentries = chaininfo->nentries;
+ point = (struct ebt_entry *)chaininfo->data;
+ counter_base = cb_base + chaininfo->counter_offset;
+ sp++;
+ continue;
+letscontinue:
+ point = (struct ebt_entry *)
+ (((char *)point) + point->next_offset);
+ i++;
+ }
+
+ // I actually like this :)
+ if (chaininfo->policy == EBT_RETURN)
+ goto letsreturn;
+ if (chaininfo->policy == EBT_ACCEPT) {
+ read_unlock_bh(&table->lock);
+ return NF_ACCEPT;
+ }
+ read_unlock_bh(&table->lock);
+ return NF_DROP;
+}
+
+// If it succeeds, returns element and locks mutex
+static inline void *
+find_inlist_lock_noload(struct list_head *head, const char *name, int *error,
+ struct semaphore *mutex)
+{
+ void *ret;
+
+ *error = down_interruptible(mutex);
+ if (*error != 0)
+ return NULL;
+
+ ret = list_named_find(head, name);
+ if (!ret) {
+ *error = -ENOENT;
+ up(mutex);
+ }
+ return ret;
+}
+
+#ifndef CONFIG_KMOD
+#define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m))
+#else
+static void *
+find_inlist_lock(struct list_head *head, const char *name, const char *prefix,
+ int *error, struct semaphore *mutex)
+{
+ void *ret;
+
+ ret = find_inlist_lock_noload(head, name, error, mutex);
+ if (!ret) {
+ char modulename[EBT_FUNCTION_MAXNAMELEN + strlen(prefix) + 1];
+ strcpy(modulename, prefix);
+ strcat(modulename, name);
+ request_module(modulename);
+ ret = find_inlist_lock_noload(head, name, error, mutex);
+ }
+ return ret;
+}
+#endif
+
+static inline struct ebt_table *
+find_table_lock(const char *name, int *error, struct semaphore *mutex)
+{
+ return find_inlist_lock(&ebt_tables, name, "ebtable_", error, mutex);
+}
+
+static inline struct ebt_match *
+find_match_lock(const char *name, int *error, struct semaphore *mutex)
+{
+ return find_inlist_lock(&ebt_matches, name, "ebt_", error, mutex);
+}
+
+static inline struct ebt_watcher *
+find_watcher_lock(const char *name, int *error, struct semaphore *mutex)
+{
+ return find_inlist_lock(&ebt_watchers, name, "ebt_", error, mutex);
+}
+
+static inline struct ebt_target *
+find_target_lock(const char *name, int *error, struct semaphore *mutex)
+{
+ return find_inlist_lock(&ebt_targets, name, "ebt_", error, mutex);
+}
+
+static inline int
+ebt_check_match(struct ebt_entry_match *m, struct ebt_entry *e,
+ const char *name, unsigned int hookmask, unsigned int *cnt)
+{
+ struct ebt_match *match;
+ int ret;
+
+ if (((char *)m) + m->match_size + sizeof(struct ebt_entry_match) >
+ ((char *)e) + e->watchers_offset)
+ return -EINVAL;
+ match = find_match_lock(m->u.name, &ret, &ebt_mutex);
+ if (!match)
+ return ret;
+ m->u.match = match;
+ if (match->me)
+ __MOD_INC_USE_COUNT(match->me);
+ up(&ebt_mutex);
+ if (match->check &&
+ match->check(name, hookmask, e, m->data, m->match_size) != 0) {
+ BUGPRINT("match->check failed\n");
+ if (match->me)
+ __MOD_DEC_USE_COUNT(match->me);
+ return -EINVAL;
+ }
+ (*cnt)++;
+ return 0;
+}
+
+static inline int
+ebt_check_watcher(struct ebt_entry_watcher *w, struct ebt_entry *e,
+ const char *name, unsigned int hookmask, unsigned int *cnt)
+{
+ struct ebt_watcher *watcher;
+ int ret;
+
+ if (((char *)w) + w->watcher_size + sizeof(struct ebt_entry_watcher) >
+ ((char *)e) + e->target_offset)
+ return -EINVAL;
+ watcher = find_watcher_lock(w->u.name, &ret, &ebt_mutex);
+ if (!watcher)
+ return ret;
+ w->u.watcher = watcher;
+ if (watcher->me)
+ __MOD_INC_USE_COUNT(watcher->me);
+ up(&ebt_mutex);
+ if (watcher->check &&
+ watcher->check(name, hookmask, e, w->data, w->watcher_size) != 0) {
+ BUGPRINT("watcher->check failed\n");
+ if (watcher->me)
+ __MOD_DEC_USE_COUNT(watcher->me);
+ return -EINVAL;
+ }
+ (*cnt)++;
+ return 0;
+}
+
+// this one is very careful, as it is the first function
+// to parse the userspace data
+static inline int
+ebt_check_entry_size_and_hooks(struct ebt_entry *e,
+ struct ebt_table_info *newinfo, char *base, char *limit,
+ struct ebt_entries **hook_entries, unsigned int *n, unsigned int *cnt,
+ unsigned int *totalcnt, unsigned int *udc_cnt, unsigned int valid_hooks)
+{
+ int i;
+
+ for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+ if ((valid_hooks & (1 << i)) == 0)
+ continue;
+ if ( (char *)hook_entries[i] - base ==
+ (char *)e - newinfo->entries)
+ break;
+ }
+ // beginning of a new chain
+ // if i == NF_BR_NUMHOOKS it must be a user defined chain
+ if (i != NF_BR_NUMHOOKS || !(e->bitmask & EBT_ENTRY_OR_ENTRIES)) {
+ if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) != 0) {
+ // we make userspace set this right,
+ // so there is no misunderstanding
+ BUGPRINT("EBT_ENTRY_OR_ENTRIES shouldn't be set "
+ "in distinguisher\n");
+ return -EINVAL;
+ }
+ // this checks if the previous chain has as many entries
+ // as it said it has
+ if (*n != *cnt) {
+ BUGPRINT("nentries does not equal the nr of entries "
+ "in the chain\n");
+ return -EINVAL;
+ }
+ // before we look at the struct, be sure it is not too big
+ if ((char *)hook_entries[i] + sizeof(struct ebt_entries)
+ > limit) {
+ BUGPRINT("entries_size too small\n");
+ return -EINVAL;
+ }
+ if (((struct ebt_entries *)e)->policy != EBT_DROP &&
+ ((struct ebt_entries *)e)->policy != EBT_ACCEPT) {
+ // only RETURN from udc
+ if (i != NF_BR_NUMHOOKS ||
+ ((struct ebt_entries *)e)->policy != EBT_RETURN) {
+ BUGPRINT("bad policy\n");
+ return -EINVAL;
+ }
+ }
+ if (i == NF_BR_NUMHOOKS) // it's a user defined chain
+ (*udc_cnt)++;
+ else
+ newinfo->hook_entry[i] = (struct ebt_entries *)e;
+ if (((struct ebt_entries *)e)->counter_offset != *totalcnt) {
+ BUGPRINT("counter_offset != totalcnt");
+ return -EINVAL;
+ }
+ *n = ((struct ebt_entries *)e)->nentries;
+ *cnt = 0;
+ return 0;
+ }
+ // a plain old entry, heh
+ if (sizeof(struct ebt_entry) > e->watchers_offset ||
+ e->watchers_offset > e->target_offset ||
+ e->target_offset >= e->next_offset) {
+ BUGPRINT("entry offsets not in right order\n");
+ return -EINVAL;
+ }
+ // this is not checked anywhere else
+ if (e->next_offset - e->target_offset < sizeof(struct ebt_entry_target)) {
+ BUGPRINT("target size too small\n");
+ return -EINVAL;
+ }
+
+ (*cnt)++;
+ (*totalcnt)++;
+ return 0;
+}
+
+struct ebt_cl_stack
+{
+ struct ebt_chainstack cs;
+ int from;
+ unsigned int hookmask;
+};
+
+// we need these positions to check that the jumps to a different part of the
+// entries is a jump to the beginning of a new chain.
+static inline int
+ebt_get_udc_positions(struct ebt_entry *e, struct ebt_table_info *newinfo,
+ struct ebt_entries **hook_entries, unsigned int *n, unsigned int valid_hooks,
+ struct ebt_cl_stack *udc)
+{
+ int i;
+
+ // we're only interested in chain starts
+ if (e->bitmask & EBT_ENTRY_OR_ENTRIES)
+ return 0;
+ for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+ if ((valid_hooks & (1 << i)) == 0)
+ continue;
+ if (newinfo->hook_entry[i] == (struct ebt_entries *)e)
+ break;
+ }
+ // only care about udc
+ if (i != NF_BR_NUMHOOKS)
+ return 0;
+
+ udc[*n].cs.chaininfo = (struct ebt_entries *)e;
+ // these initialisations are depended on later in check_chainloops()
+ udc[*n].cs.n = 0;
+ udc[*n].hookmask = 0;
+
+ (*n)++;
+ return 0;
+}
+
+static inline int
+ebt_cleanup_match(struct ebt_entry_match *m, unsigned int *i)
+{
+ if (i && (*i)-- == 0)
+ return 1;
+ if (m->u.match->destroy)
+ m->u.match->destroy(m->data, m->match_size);
+ if (m->u.match->me)
+ __MOD_DEC_USE_COUNT(m->u.match->me);
+
+ return 0;
+}
+
+static inline int
+ebt_cleanup_watcher(struct ebt_entry_watcher *w, unsigned int *i)
+{
+ if (i && (*i)-- == 0)
+ return 1;
+ if (w->u.watcher->destroy)
+ w->u.watcher->destroy(w->data, w->watcher_size);
+ if (w->u.watcher->me)
+ __MOD_DEC_USE_COUNT(w->u.watcher->me);
+
+ return 0;
+}
+
+static inline int
+ebt_cleanup_entry(struct ebt_entry *e, unsigned int *cnt)
+{
+ struct ebt_entry_target *t;
+
+ if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0)
+ return 0;
+ // we're done
+ if (cnt && (*cnt)-- == 0)
+ return 1;
+ EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, NULL);
+ EBT_MATCH_ITERATE(e, ebt_cleanup_match, NULL);
+ t = (struct ebt_entry_target *)(((char *)e) + e->target_offset);
+ if (t->u.target->destroy)
+ t->u.target->destroy(t->data, t->target_size);
+ if (t->u.target->me)
+ __MOD_DEC_USE_COUNT(t->u.target->me);
+
+ return 0;
+}
+
+static inline int
+ebt_check_entry(struct ebt_entry *e, struct ebt_table_info *newinfo,
+ const char *name, unsigned int *cnt, unsigned int valid_hooks,
+ struct ebt_cl_stack *cl_s, unsigned int udc_cnt)
+{
+ struct ebt_entry_target *t;
+ struct ebt_target *target;
+ unsigned int i, j, hook = 0, hookmask = 0;
+ int ret;
+
+ // Don't mess with the struct ebt_entries
+ if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0)
+ return 0;
+
+ if (e->bitmask & ~EBT_F_MASK) {
+ BUGPRINT("Unknown flag for bitmask\n");
+ return -EINVAL;
+ }
+ if (e->invflags & ~EBT_INV_MASK) {
+ BUGPRINT("Unknown flag for inv bitmask\n");
+ return -EINVAL;
+ }
+ if ( (e->bitmask & EBT_NOPROTO) && (e->bitmask & EBT_802_3) ) {
+ BUGPRINT("NOPROTO & 802_3 not allowed\n");
+ return -EINVAL;
+ }
+ // what hook do we belong to?
+ for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+ if ((valid_hooks & (1 << i)) == 0)
+ continue;
+ if ((char *)newinfo->hook_entry[i] < (char *)e)
+ hook = i;
+ else
+ break;
+ }
+ // (1 << NF_BR_NUMHOOKS) tells the check functions the rule is on
+ // a base chain
+ if (i < NF_BR_NUMHOOKS)
+ hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS);
+ else {
+ for (i = 0; i < udc_cnt; i++)
+ if ((char *)(cl_s[i].cs.chaininfo) > (char *)e)
+ break;
+ if (i == 0)
+ hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS);
+ else
+ hookmask = cl_s[i - 1].hookmask;
+ }
+ i = 0;
+ ret = EBT_MATCH_ITERATE(e, ebt_check_match, e, name, hookmask, &i);
+ if (ret != 0)
+ goto cleanup_matches;
+ j = 0;
+ ret = EBT_WATCHER_ITERATE(e, ebt_check_watcher, e, name, hookmask, &j);
+ if (ret != 0)
+ goto cleanup_watchers;
+ t = (struct ebt_entry_target *)(((char *)e) + e->target_offset);
+ target = find_target_lock(t->u.name, &ret, &ebt_mutex);
+ if (!target)
+ goto cleanup_watchers;
+ if (target->me)
+ __MOD_INC_USE_COUNT(target->me);
+ up(&ebt_mutex);
+
+ t->u.target = target;
+ if (t->u.target == &ebt_standard_target) {
+ if (e->target_offset + sizeof(struct ebt_standard_target) >
+ e->next_offset) {
+ BUGPRINT("Standard target size too big\n");
+ ret = -EFAULT;
+ goto cleanup_watchers;
+ }
+ if (((struct ebt_standard_target *)t)->verdict <
+ -NUM_STANDARD_TARGETS) {
+ BUGPRINT("Invalid standard target\n");
+ ret = -EFAULT;
+ goto cleanup_watchers;
+ }
+ } else if ((e->target_offset + t->target_size +
+ sizeof(struct ebt_entry_target) > e->next_offset) ||
+ (t->u.target->check &&
+ t->u.target->check(name, hookmask, e, t->data, t->target_size) != 0)){
+ if (t->u.target->me)
+ __MOD_DEC_USE_COUNT(t->u.target->me);
+ ret = -EFAULT;
+ goto cleanup_watchers;
+ }
+ (*cnt)++;
+ return 0;
+cleanup_watchers:
+ EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, &j);
+cleanup_matches:
+ EBT_MATCH_ITERATE(e, ebt_cleanup_match, &i);
+ return ret;
+}
+
+// checks for loops and sets the hook mask for udc
+// the hook mask for udc tells us from which base chains the udc can be
+// accessed. This mask is a parameter to the check() functions of the extensions
+int check_chainloops(struct ebt_entries *chain, struct ebt_cl_stack *cl_s,
+ unsigned int udc_cnt, unsigned int hooknr, char *base)
+{
+ int i, chain_nr = -1, pos = 0, nentries = chain->nentries, verdict;
+ struct ebt_entry *e = (struct ebt_entry *)chain->data;
+ struct ebt_entry_target *t;
+
+ while (pos < nentries || chain_nr != -1) {
+ // end of udc, go back one 'recursion' step
+ if (pos == nentries) {
+ // put back values of the time when this chain was called
+ e = cl_s[chain_nr].cs.e;
+ if (cl_s[chain_nr].from != -1)
+ nentries =
+ cl_s[cl_s[chain_nr].from].cs.chaininfo->nentries;
+ else
+ nentries = chain->nentries;
+ pos = cl_s[chain_nr].cs.n;
+ // make sure we won't see a loop that isn't one
+ cl_s[chain_nr].cs.n = 0;
+ chain_nr = cl_s[chain_nr].from;
+ if (pos == nentries)
+ continue;
+ }
+ t = (struct ebt_entry_target *)
+ (((char *)e) + e->target_offset);
+ if (strcmp(t->u.name, EBT_STANDARD_TARGET))
+ goto letscontinue;
+ if (e->target_offset + sizeof(struct ebt_standard_target) >
+ e->next_offset) {
+ BUGPRINT("Standard target size too big\n");
+ return -1;
+ }
+ verdict = ((struct ebt_standard_target *)t)->verdict;
+ if (verdict >= 0) { // jump to another chain
+ struct ebt_entries *hlp2 =
+ (struct ebt_entries *)(base + verdict);
+ for (i = 0; i < udc_cnt; i++)
+ if (hlp2 == cl_s[i].cs.chaininfo)
+ break;
+ // bad destination or loop
+ if (i == udc_cnt) {
+ BUGPRINT("bad destination\n");
+ return -1;
+ }
+ if (cl_s[i].cs.n) {
+ BUGPRINT("loop\n");
+ return -1;
+ }
+ // this can't be 0, so the above test is correct
+ cl_s[i].cs.n = pos + 1;
+ pos = 0;
+ cl_s[i].cs.e = ((void *)e + e->next_offset);
+ e = (struct ebt_entry *)(hlp2->data);
+ nentries = hlp2->nentries;
+ cl_s[i].from = chain_nr;
+ chain_nr = i;
+ // this udc is accessible from the base chain for hooknr
+ cl_s[i].hookmask |= (1 << hooknr);
+ continue;
+ }
+letscontinue:
+ e = (void *)e + e->next_offset;
+ pos++;
+ }
+ return 0;
+}
+
+// do the parsing of the table/chains/entries/matches/watchers/targets, heh
+static int translate_table(struct ebt_replace *repl,
+ struct ebt_table_info *newinfo)
+{
+ unsigned int i, j, k, udc_cnt;
+ int ret;
+ struct ebt_cl_stack *cl_s = NULL; // used in the checking for chain loops
+
+ i = 0;
+ while (i < NF_BR_NUMHOOKS && !(repl->valid_hooks & (1 << i)))
+ i++;
+ if (i == NF_BR_NUMHOOKS) {
+ BUGPRINT("No valid hooks specified\n");
+ return -EINVAL;
+ }
+ if (repl->hook_entry[i] != (struct ebt_entries *)repl->entries) {
+ BUGPRINT("Chains don't start at beginning\n");
+ return -EINVAL;
+ }
+ // make sure chains are ordered after each other in same order
+ // as their corresponding hooks
+ for (j = i + 1; j < NF_BR_NUMHOOKS; j++) {
+ if (!(repl->valid_hooks & (1 << j)))
+ continue;
+ if ( repl->hook_entry[j] <= repl->hook_entry[i] ) {
+ BUGPRINT("Hook order must be followed\n");
+ return -EINVAL;
+ }
+ i = j;
+ }
+
+ for (i = 0; i < NF_BR_NUMHOOKS; i++)
+ newinfo->hook_entry[i] = NULL;
+
+ newinfo->entries_size = repl->entries_size;
+ newinfo->nentries = repl->nentries;
+
+ // do some early checkings and initialize some things
+ i = 0; // holds the expected nr. of entries for the chain
+ j = 0; // holds the up to now counted entries for the chain
+ k = 0; // holds the total nr. of entries, should equal
+ // newinfo->nentries afterwards
+ udc_cnt = 0; // will hold the nr. of user defined chains (udc)
+ ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+ ebt_check_entry_size_and_hooks, newinfo, repl->entries,
+ repl->entries + repl->entries_size, repl->hook_entry, &i, &j, &k,
+ &udc_cnt, repl->valid_hooks);
+
+ if (ret != 0)
+ return ret;
+
+ if (i != j) {
+ BUGPRINT("nentries does not equal the nr of entries in the "
+ "(last) chain\n");
+ return -EINVAL;
+ }
+ if (k != newinfo->nentries) {
+ BUGPRINT("Total nentries is wrong\n");
+ return -EINVAL;
+ }
+
+ // check if all valid hooks have a chain
+ for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+ if (newinfo->hook_entry[i] == NULL &&
+ (repl->valid_hooks & (1 << i))) {
+ BUGPRINT("Valid hook without chain\n");
+ return -EINVAL;
+ }
+ }
+
+ // Get the location of the udc, put them in an array
+ // While we're at it, allocate the chainstack
+ if (udc_cnt) {
+ // this will get free'd in do_replace()/ebt_register_table()
+ // if an error occurs
+ newinfo->chainstack = (struct ebt_chainstack **)
+ vmalloc(NR_CPUS * sizeof(struct ebt_chainstack));
+ if (!newinfo->chainstack)
+ return -ENOMEM;
+ for (i = 0; i < NR_CPUS; i++) {
+ newinfo->chainstack[i] =
+ vmalloc(udc_cnt * sizeof(struct ebt_chainstack));
+ if (!newinfo->chainstack[i]) {
+ while (i)
+ vfree(newinfo->chainstack[--i]);
+ vfree(newinfo->chainstack);
+ newinfo->chainstack = NULL;
+ return -ENOMEM;
+ }
+ }
+
+ cl_s = (struct ebt_cl_stack *)
+ vmalloc(udc_cnt * sizeof(struct ebt_cl_stack));
+ if (!cl_s)
+ return -ENOMEM;
+ i = 0; // the i'th udc
+ EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+ ebt_get_udc_positions, newinfo, repl->hook_entry, &i,
+ repl->valid_hooks, cl_s);
+ // sanity check
+ if (i != udc_cnt) {
+ BUGPRINT("i != udc_cnt\n");
+ vfree(cl_s);
+ return -EFAULT;
+ }
+ }
+
+ // Check for loops
+ for (i = 0; i < NF_BR_NUMHOOKS; i++)
+ if (repl->valid_hooks & (1 << i))
+ if (check_chainloops(newinfo->hook_entry[i],
+ cl_s, udc_cnt, i, newinfo->entries)) {
+ if (cl_s)
+ vfree(cl_s);
+ return -EINVAL;
+ }
+
+ // we now know the following (along with E=mc˛):
+ // - the nr of entries in each chain is right
+ // - the size of the allocated space is right
+ // - all valid hooks have a corresponding chain
+ // - there are no loops
+ // - wrong data can still be on the level of a single entry
+ // - could be there are jumps to places that are not the
+ // beginning of a chain. This can only occur in chains that
+ // are not accessible from any base chains, so we don't care.
+
+ // used to know what we need to clean up if something goes wrong
+ i = 0;
+ ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+ ebt_check_entry, newinfo, repl->name, &i, repl->valid_hooks,
+ cl_s, udc_cnt);
+ if (ret != 0) {
+ EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+ ebt_cleanup_entry, &i);
+ }
+ if (cl_s)
+ vfree(cl_s);
+ return ret;
+}
+
+// called under write_lock
+static void get_counters(struct ebt_counter *oldcounters,
+ struct ebt_counter *counters, unsigned int nentries)
+{
+ int i, cpu;
+ struct ebt_counter *counter_base;
+
+ // counters of cpu 0
+ memcpy(counters, oldcounters,
+ sizeof(struct ebt_counter) * nentries);
+ // add other counters to those of cpu 0
+ for (cpu = 1; cpu < NR_CPUS; cpu++) {
+ counter_base = COUNTER_BASE(oldcounters, nentries, cpu);
+ for (i = 0; i < nentries; i++)
+ counters[i].pcnt += counter_base[i].pcnt;
+ }
+}
+
+// replace the table
+static int do_replace(void *user, unsigned int len)
+{
+ int ret, i, countersize;
+ struct ebt_table_info *newinfo;
+ struct ebt_replace tmp;
+ struct ebt_table *t;
+ struct ebt_counter *counterstmp = NULL;
+ // used to be able to unlock earlier
+ struct ebt_table_info *table;
+
+ if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
+ return -EFAULT;
+
+ if (len != sizeof(tmp) + tmp.entries_size) {
+ BUGPRINT("Wrong len argument\n");
+ return -EINVAL;
+ }
+
+ if (tmp.entries_size == 0) {
+ BUGPRINT("Entries_size never zero\n");
+ return -EINVAL;
+ }
+ countersize = COUNTER_OFFSET(tmp.nentries) * NR_CPUS;
+ newinfo = (struct ebt_table_info *)
+ vmalloc(sizeof(struct ebt_table_info) + countersize);
+ if (!newinfo)
+ return -ENOMEM;
+
+ if (countersize)
+ memset(newinfo->counters, 0, countersize);
+
+ newinfo->entries = (char *)vmalloc(tmp.entries_size);
+ if (!newinfo->entries) {
+ ret = -ENOMEM;
+ goto free_newinfo;
+ }
+ if (copy_from_user(
+ newinfo->entries, tmp.entries, tmp.entries_size) != 0) {
+ BUGPRINT("Couldn't copy entries from userspace\n");
+ ret = -EFAULT;
+ goto free_entries;
+ }
+
+ // the user wants counters back
+ // the check on the size is done later, when we have the lock
+ if (tmp.num_counters) {
+ counterstmp = (struct ebt_counter *)
+ vmalloc(tmp.num_counters * sizeof(struct ebt_counter));
+ if (!counterstmp) {
+ ret = -ENOMEM;
+ goto free_entries;
+ }
+ }
+ else
+ counterstmp = NULL;
+
+ // this can get initialized by translate_table()
+ newinfo->chainstack = NULL;
+ ret = translate_table(&tmp, newinfo);
+
+ if (ret != 0)
+ goto free_counterstmp;
+
+ t = find_table_lock(tmp.name, &ret, &ebt_mutex);
+ if (!t)
+ goto free_iterate;
+
+ // the table doesn't like it
+ if (t->check && (ret = t->check(newinfo, tmp.valid_hooks)))
+ goto free_unlock;
+
+ if (tmp.num_counters && tmp.num_counters != t->private->nentries) {
+ BUGPRINT("Wrong nr. of counters requested\n");
+ ret = -EINVAL;
+ goto free_unlock;
+ }
+
+ // we have the mutex lock, so no danger in reading this pointer
+ table = t->private;
+ // we need an atomic snapshot of the counters
+ write_lock_bh(&t->lock);
+ if (tmp.num_counters)
+ get_counters(t->private->counters, counterstmp,
+ t->private->nentries);
+
+ t->private = newinfo;
+ write_unlock_bh(&t->lock);
+ up(&ebt_mutex);
+ // So, a user can change the chains while having messed up her counter
+ // allocation. Only reason why this is done is because this way the lock
+ // is held only once, while this doesn't bring the kernel into a
+ // dangerous state.
+ if (tmp.num_counters &&
+ copy_to_user(tmp.counters, counterstmp,
+ tmp.num_counters * sizeof(struct ebt_counter))) {
+ BUGPRINT("Couldn't copy counters to userspace\n");
+ ret = -EFAULT;
+ }
+ else
+ ret = 0;
+
+ // decrease module count and free resources
+ EBT_ENTRY_ITERATE(table->entries, table->entries_size,
+ ebt_cleanup_entry, NULL);
+
+ vfree(table->entries);
+ if (table->chainstack) {
+ for (i = 0; i < NR_CPUS; i++)
+ vfree(table->chainstack[i]);
+ vfree(table->chainstack);
+ }
+ vfree(table);
+
+ if (counterstmp)
+ vfree(counterstmp);
+ return ret;
+
+free_unlock:
+ up(&ebt_mutex);
+free_iterate:
+ EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+ ebt_cleanup_entry, NULL);
+free_counterstmp:
+ if (counterstmp)
+ vfree(counterstmp);
+ // can be initialized in translate_table()
+ if (newinfo->chainstack) {
+ for (i = 0; i < NR_CPUS; i++)
+ vfree(newinfo->chainstack[i]);
+ vfree(newinfo->chainstack);
+ }
+free_entries:
+ if (newinfo->entries)
+ vfree(newinfo->entries);
+free_newinfo:
+ if (newinfo)
+ vfree(newinfo);
+ return ret;
+}
+
+int ebt_register_target(struct ebt_target *target)
+{
+ int ret;
+
+ ret = down_interruptible(&ebt_mutex);
+ if (ret != 0)
+ return ret;
+ if (!list_named_insert(&ebt_targets, target)) {
+ up(&ebt_mutex);
+ return -EEXIST;
+ }
+ up(&ebt_mutex);
+ MOD_INC_USE_COUNT;
+
+ return 0;
+}
+
+void ebt_unregister_target(struct ebt_target *target)
+{
+ down(&ebt_mutex);
+ LIST_DELETE(&ebt_targets, target);
+ up(&ebt_mutex);
+ MOD_DEC_USE_COUNT;
+}
+
+int ebt_register_match(struct ebt_match *match)
+{
+ int ret;
+
+ ret = down_interruptible(&ebt_mutex);
+ if (ret != 0)
+ return ret;
+ if (!list_named_insert(&ebt_matches, match)) {
+ up(&ebt_mutex);
+ return -EEXIST;
+ }
+ up(&ebt_mutex);
+ MOD_INC_USE_COUNT;
+
+ return 0;
+}
+
+void ebt_unregister_match(struct ebt_match *match)
+{
+ down(&ebt_mutex);
+ LIST_DELETE(&ebt_matches, match);
+ up(&ebt_mutex);
+ MOD_DEC_USE_COUNT;
+}
+
+int ebt_register_watcher(struct ebt_watcher *watcher)
+{
+ int ret;
+
+ ret = down_interruptible(&ebt_mutex);
+ if (ret != 0)
+ return ret;
+ if (!list_named_insert(&ebt_watchers, watcher)) {
+ up(&ebt_mutex);
+ return -EEXIST;
+ }
+ up(&ebt_mutex);
+ MOD_INC_USE_COUNT;
+
+ return 0;
+}
+
+void ebt_unregister_watcher(struct ebt_watcher *watcher)
+{
+ down(&ebt_mutex);
+ LIST_DELETE(&ebt_watchers, watcher);
+ up(&ebt_mutex);
+ MOD_DEC_USE_COUNT;
+}
+
+int ebt_register_table(struct ebt_table *table)
+{
+ struct ebt_table_info *newinfo;
+ int ret, i, countersize;
+
+ if (!table || !table->table ||!table->table->entries ||
+ table->table->entries_size == 0 ||
+ table->table->counters || table->private) {
+ BUGPRINT("Bad table data for ebt_register_table!!!\n");
+ return -EINVAL;
+ }
+
+ countersize = COUNTER_OFFSET(table->table->nentries) * NR_CPUS;
+ newinfo = (struct ebt_table_info *)
+ vmalloc(sizeof(struct ebt_table_info) + countersize);
+ ret = -ENOMEM;
+ if (!newinfo)
+ return -ENOMEM;
+
+ newinfo->entries = (char *)vmalloc(table->table->entries_size);
+ if (!(newinfo->entries))
+ goto free_newinfo;
+
+ memcpy(newinfo->entries, table->table->entries,
+ table->table->entries_size);
+
+ if (countersize)
+ memset(newinfo->counters, 0, countersize);
+
+ // fill in newinfo and parse the entries
+ newinfo->chainstack = NULL;
+ ret = translate_table(table->table, newinfo);
+ if (ret != 0) {
+ BUGPRINT("Translate_table failed\n");
+ goto free_chainstack;
+ }
+
+ if (table->check && table->check(newinfo, table->valid_hooks)) {
+ BUGPRINT("The table doesn't like its own initial data, lol\n");
+ return -EINVAL;
+ }
+
+ table->private = newinfo;
+ table->lock = RW_LOCK_UNLOCKED;
+ ret = down_interruptible(&ebt_mutex);
+ if (ret != 0)
+ goto free_chainstack;
+
+ if (list_named_find(&ebt_tables, table->name)) {
+ ret = -EEXIST;
+ BUGPRINT("Table name already exists\n");
+ goto free_unlock;
+ }
+
+ list_prepend(&ebt_tables, table);
+ up(&ebt_mutex);
+ MOD_INC_USE_COUNT;
+ return 0;
+free_unlock:
+ up(&ebt_mutex);
+free_chainstack:
+ if (newinfo->chainstack) {
+ for (i = 0; i < NR_CPUS; i++)
+ vfree(newinfo->chainstack[i]);
+ vfree(newinfo->chainstack);
+ }
+ vfree(newinfo->entries);
+free_newinfo:
+ vfree(newinfo);
+ return ret;
+}
+
+void ebt_unregister_table(struct ebt_table *table)
+{
+ int i;
+
+ if (!table) {
+ BUGPRINT("Request to unregister NULL table!!!\n");
+ return;
+ }
+ down(&ebt_mutex);
+ LIST_DELETE(&ebt_tables, table);
+ up(&ebt_mutex);
+ EBT_ENTRY_ITERATE(table->private->entries,
+ table->private->entries_size, ebt_cleanup_entry, NULL);
+ if (table->private->entries)
+ vfree(table->private->entries);
+ if (table->private->chainstack) {
+ for (i = 0; i < NR_CPUS; i++)
+ vfree(table->private->chainstack[i]);
+ vfree(table->private->chainstack);
+ }
+ vfree(table->private);
+ MOD_DEC_USE_COUNT;
+}
+
+// userspace just supplied us with counters
+static int update_counters(void *user, unsigned int len)
+{
+ int i, ret;
+ struct ebt_counter *tmp;
+ struct ebt_replace hlp;
+ struct ebt_table *t;
+
+ if (copy_from_user(&hlp, user, sizeof(hlp)))
+ return -EFAULT;
+
+ if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter))
+ return -EINVAL;
+ if (hlp.num_counters == 0)
+ return -EINVAL;
+
+ if ( !(tmp = (struct ebt_counter *)
+ vmalloc(hlp.num_counters * sizeof(struct ebt_counter))) ){
+ MEMPRINT("Update_counters && nomemory\n");
+ return -ENOMEM;
+ }
+
+ t = find_table_lock(hlp.name, &ret, &ebt_mutex);
+ if (!t)
+ goto free_tmp;
+
+ if (hlp.num_counters != t->private->nentries) {
+ BUGPRINT("Wrong nr of counters\n");
+ ret = -EINVAL;
+ goto unlock_mutex;
+ }
+
+ if ( copy_from_user(tmp, hlp.counters,
+ hlp.num_counters * sizeof(struct ebt_counter)) ) {
+ BUGPRINT("Updata_counters && !cfu\n");
+ ret = -EFAULT;
+ goto unlock_mutex;
+ }
+
+ // we want an atomic add of the counters
+ write_lock_bh(&t->lock);
+
+ // we add to the counters of the first cpu
+ for (i = 0; i < hlp.num_counters; i++)
+ t->private->counters[i].pcnt += tmp[i].pcnt;
+
+ write_unlock_bh(&t->lock);
+ ret = 0;
+unlock_mutex:
+ up(&ebt_mutex);
+free_tmp:
+ vfree(tmp);
+ return ret;
+}
+
+static inline int ebt_make_matchname(struct ebt_entry_match *m,
+ char *base, char *ubase)
+{
+ char *hlp = ubase - base + (char *)m;
+ if (copy_to_user(hlp, m->u.match->name, EBT_FUNCTION_MAXNAMELEN))
+ return -EFAULT;
+ return 0;
+}
+
+static inline int ebt_make_watchername(struct ebt_entry_watcher *w,
+ char *base, char *ubase)
+{
+ char *hlp = ubase - base + (char *)w;
+ if (copy_to_user(hlp , w->u.watcher->name, EBT_FUNCTION_MAXNAMELEN))
+ return -EFAULT;
+ return 0;
+}
+
+static inline int ebt_make_names(struct ebt_entry *e, char *base, char *ubase)
+{
+ int ret;
+ char *hlp;
+ struct ebt_entry_target *t;
+
+ if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0)
+ return 0;
+
+ hlp = ubase - base + (char *)e + e->target_offset;
+ t = (struct ebt_entry_target *)(((char *)e) + e->target_offset);
+
+ ret = EBT_MATCH_ITERATE(e, ebt_make_matchname, base, ubase);
+ if (ret != 0)
+ return ret;
+ ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase);
+ if (ret != 0)
+ return ret;
+ if (copy_to_user(hlp, t->u.target->name, EBT_FUNCTION_MAXNAMELEN))
+ return -EFAULT;
+ return 0;
+}
+
+// called with ebt_mutex down
+static int copy_everything_to_user(struct ebt_table *t, void *user,
+ int *len, int cmd)
+{
+ struct ebt_replace tmp;
+ struct ebt_counter *counterstmp, *oldcounters;
+ unsigned int entries_size, nentries;
+ char *entries;
+
+ if (cmd == EBT_SO_GET_ENTRIES) {
+ entries_size = t->private->entries_size;
+ nentries = t->private->nentries;
+ entries = t->private->entries;
+ oldcounters = t->private->counters;
+ } else {
+ entries_size = t->table->entries_size;
+ nentries = t->table->nentries;
+ entries = t->table->entries;
+ oldcounters = t->table->counters;
+ }
+
+ if (copy_from_user(&tmp, user, sizeof(tmp))) {
+ BUGPRINT("Cfu didn't work\n");
+ return -EFAULT;
+ }
+
+ if (*len != sizeof(struct ebt_replace) + entries_size +
+ (tmp.num_counters? nentries * sizeof(struct ebt_counter): 0)) {
+ BUGPRINT("Wrong size\n");
+ return -EINVAL;
+ }
+
+ if (tmp.nentries != nentries) {
+ BUGPRINT("Nentries wrong\n");
+ return -EINVAL;
+ }
+
+ if (tmp.entries_size != entries_size) {
+ BUGPRINT("Wrong size\n");
+ return -EINVAL;
+ }
+
+ // userspace might not need the counters
+ if (tmp.num_counters) {
+ if (tmp.num_counters != nentries) {
+ BUGPRINT("Num_counters wrong\n");
+ return -EINVAL;
+ }
+ counterstmp = (struct ebt_counter *)
+ vmalloc(nentries * sizeof(struct ebt_counter));
+ if (!counterstmp) {
+ MEMPRINT("Couldn't copy counters, out of memory\n");
+ return -ENOMEM;
+ }
+ write_lock_bh(&t->lock);
+ get_counters(oldcounters, counterstmp, nentries);
+ write_unlock_bh(&t->lock);
+
+ if (copy_to_user(tmp.counters, counterstmp,
+ nentries * sizeof(struct ebt_counter))) {
+ BUGPRINT("Couldn't copy counters to userspace\n");
+ vfree(counterstmp);
+ return -EFAULT;
+ }
+ vfree(counterstmp);
+ }
+
+ if (copy_to_user(tmp.entries, entries, entries_size)) {
+ BUGPRINT("Couldn't copy entries to userspace\n");
+ return -EFAULT;
+ }
+ // set the match/watcher/target names right
+ return EBT_ENTRY_ITERATE(entries, entries_size,
+ ebt_make_names, entries, tmp.entries);
+}
+
+static int do_ebt_set_ctl(struct sock *sk,
+ int cmd, void *user, unsigned int len)
+{
+ int ret;
+
+ switch(cmd) {
+ case EBT_SO_SET_ENTRIES:
+ ret = do_replace(user, len);
+ break;
+ case EBT_SO_SET_COUNTERS:
+ ret = update_counters(user, len);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ return ret;
+}
+
+static int do_ebt_get_ctl(struct sock *sk, int cmd, void *user, int *len)
+{
+ int ret;
+ struct ebt_replace tmp;
+ struct ebt_table *t;
+
+ if (copy_from_user(&tmp, user, sizeof(tmp)))
+ return -EFAULT;
+
+ t = find_table_lock(tmp.name, &ret, &ebt_mutex);
+ if (!t)
+ return ret;
+
+ switch(cmd) {
+ case EBT_SO_GET_INFO:
+ case EBT_SO_GET_INIT_INFO:
+ if (*len != sizeof(struct ebt_replace)){
+ ret = -EINVAL;
+ up(&ebt_mutex);
+ break;
+ }
+ if (cmd == EBT_SO_GET_INFO) {
+ tmp.nentries = t->private->nentries;
+ tmp.entries_size = t->private->entries_size;
+ tmp.valid_hooks = t->valid_hooks;
+ } else {
+ tmp.nentries = t->table->nentries;
+ tmp.entries_size = t->table->entries_size;
+ tmp.valid_hooks = t->table->valid_hooks;
+ }
+ up(&ebt_mutex);
+ if (copy_to_user(user, &tmp, *len) != 0){
+ BUGPRINT("c2u Didn't work\n");
+ ret = -EFAULT;
+ break;
+ }
+ ret = 0;
+ break;
+
+ case EBT_SO_GET_ENTRIES:
+ case EBT_SO_GET_INIT_ENTRIES:
+ ret = copy_everything_to_user(t, user, len, cmd);
+ up(&ebt_mutex);
+ break;
+
+ default:
+ up(&ebt_mutex);
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static struct nf_sockopt_ops ebt_sockopts =
+{ { NULL, NULL }, PF_INET, EBT_BASE_CTL, EBT_SO_SET_MAX + 1, do_ebt_set_ctl,
+ EBT_BASE_CTL, EBT_SO_GET_MAX + 1, do_ebt_get_ctl, 0, NULL
+};
+
+static int __init init(void)
+{
+ int ret;
+
+ down(&ebt_mutex);
+ list_named_insert(&ebt_targets, &ebt_standard_target);
+ up(&ebt_mutex);
+ if ((ret = nf_register_sockopt(&ebt_sockopts)) < 0)
+ return ret;
+
+ printk("Ebtables v2.0 registered");
+ return 0;
+}
+
+static void __exit fini(void)
+{
+ nf_unregister_sockopt(&ebt_sockopts);
+ printk("Ebtables v2.0 unregistered");
+}
+
+EXPORT_SYMBOL(ebt_register_table);
+EXPORT_SYMBOL(ebt_unregister_table);
+EXPORT_SYMBOL(ebt_register_match);
+EXPORT_SYMBOL(ebt_unregister_match);
+EXPORT_SYMBOL(ebt_register_watcher);
+EXPORT_SYMBOL(ebt_unregister_watcher);
+EXPORT_SYMBOL(ebt_register_target);
+EXPORT_SYMBOL(ebt_unregister_target);
+EXPORT_SYMBOL(ebt_do_table);
+module_init(init);
+module_exit(fini);
+MODULE_LICENSE("GPL");