diff options
author | Harald Welte <laforge@netfilter.org> | 2006-01-12 13:30:04 -0800 |
---|---|---|
committer | David S. Miller <davem@sunset.davemloft.net> | 2006-01-12 14:06:43 -0800 |
commit | 2e4e6a17af35be359cc8f1c924f8f198fbd478cc (patch) | |
tree | cb4b5438dcf9ff9d57518a26124308bcbfffd214 /net/ipv4/netfilter/ip_tables.c | |
parent | 880b005f294454d989783d0984dc554dfe3c8214 (diff) |
[NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables
This monster-patch tries to do the best job for unifying the data
structures and backend interfaces for the three evil clones ip_tables,
ip6_tables and arp_tables. In an ideal world we would never have
allowed this kind of copy+paste programming... but well, our world
isn't (yet?) ideal.
o introduce a new x_tables module
o {ip,arp,ip6}_tables depend on this x_tables module
o registration functions for tables, matches and targets are only
wrappers around x_tables provided functions
o all matches/targets that are used from ip_tables and ip6_tables
are now implemented as xt_FOOBAR.c files and provide module aliases
to ipt_FOOBAR and ip6t_FOOBAR
o header files for xt_matches are in include/linux/netfilter/,
include/linux/netfilter_{ipv4,ipv6} contains compatibility wrappers
around the xt_FOOBAR.h headers
Based on this patchset we're going to further unify the code,
gradually getting rid of all the layer 3 specific assumptions.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/netfilter/ip_tables.c')
-rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 842 |
1 files changed, 95 insertions, 747 deletions
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 877bc96d333..2371b2062c2 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -2,7 +2,7 @@ * Packet matching code. * * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling - * Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org> + * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -11,6 +11,8 @@ * 19 Jan 2002 Harald Welte <laforge@gnumonks.org> * - increase module usage count as soon as we have rules inside * a table + * 08 Oct 2005 Harald Welte <lafore@netfilter.org> + * - Generalize into "x_tables" layer and "{ip,ip6,arp}_tables" */ #include <linux/config.h> #include <linux/cache.h> @@ -20,8 +22,6 @@ #include <linux/vmalloc.h> #include <linux/netdevice.h> #include <linux/module.h> -#include <linux/tcp.h> -#include <linux/udp.h> #include <linux/icmp.h> #include <net/ip.h> #include <asm/uaccess.h> @@ -30,6 +30,7 @@ #include <linux/err.h> #include <linux/cpumask.h> +#include <linux/netfilter/x_tables.h> #include <linux/netfilter_ipv4/ip_tables.h> MODULE_LICENSE("GPL"); @@ -62,14 +63,6 @@ do { \ #else #define IP_NF_ASSERT(x) #endif -#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) - -static DECLARE_MUTEX(ipt_mutex); - -/* Must have mutex */ -#define ASSERT_READ_LOCK(x) IP_NF_ASSERT(down_trylock(&ipt_mutex) != 0) -#define ASSERT_WRITE_LOCK(x) IP_NF_ASSERT(down_trylock(&ipt_mutex) != 0) -#include <linux/netfilter_ipv4/listhelp.h> #if 0 /* All the better to debug you with... */ @@ -86,36 +79,6 @@ static DECLARE_MUTEX(ipt_mutex); Hence the start of any table is given by get_table() below. */ -/* The table itself */ -struct ipt_table_info -{ - /* Size per table */ - unsigned int size; - /* Number of entries: FIXME. --RR */ - unsigned int number; - /* Initial number of entries. Needed for module usage count */ - unsigned int initial_entries; - - /* Entry points and underflows */ - unsigned int hook_entry[NF_IP_NUMHOOKS]; - unsigned int underflow[NF_IP_NUMHOOKS]; - - /* ipt_entry tables: one per CPU */ - void *entries[NR_CPUS]; -}; - -static LIST_HEAD(ipt_target); -static LIST_HEAD(ipt_match); -static LIST_HEAD(ipt_tables); -#define SET_COUNTER(c,b,p) do { (c).bcnt = (b); (c).pcnt = (p); } while(0) -#define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0) - -#if 0 -#define down(x) do { printk("DOWN:%u:" #x "\n", __LINE__); down(x); } while(0) -#define down_interruptible(x) ({ int __r; printk("DOWNi:%u:" #x "\n", __LINE__); __r = down_interruptible(x); if (__r != 0) printk("ABORT-DOWNi:%u\n", __LINE__); __r; }) -#define up(x) do { printk("UP:%u:" #x "\n", __LINE__); up(x); } while(0) -#endif - /* Returns whether matches rule or not. */ static inline int ip_packet_match(const struct iphdr *ip, @@ -234,7 +197,8 @@ int do_match(struct ipt_entry_match *m, int *hotdrop) { /* Stop iteration if it doesn't match */ - if (!m->u.kernel.match->match(skb, in, out, m->data, offset, hotdrop)) + if (!m->u.kernel.match->match(skb, in, out, m->data, offset, + skb->nh.iph->ihl*4, hotdrop)) return 1; else return 0; @@ -265,6 +229,7 @@ ipt_do_table(struct sk_buff **pskb, const char *indev, *outdev; void *table_base; struct ipt_entry *e, *back; + struct xt_table_info *private = table->private; /* Initialization */ ip = (*pskb)->nh.iph; @@ -281,24 +246,11 @@ ipt_do_table(struct sk_buff **pskb, read_lock_bh(&table->lock); IP_NF_ASSERT(table->valid_hooks & (1 << hook)); - table_base = (void *)table->private->entries[smp_processor_id()]; - e = get_entry(table_base, table->private->hook_entry[hook]); - -#ifdef CONFIG_NETFILTER_DEBUG - /* Check noone else using our table */ - if (((struct ipt_entry *)table_base)->comefrom != 0xdead57ac - && ((struct ipt_entry *)table_base)->comefrom != 0xeeeeeeec) { - printk("ASSERT: CPU #%u, %s comefrom(%p) = %X\n", - smp_processor_id(), - table->name, - &((struct ipt_entry *)table_base)->comefrom, - ((struct ipt_entry *)table_base)->comefrom); - } - ((struct ipt_entry *)table_base)->comefrom = 0x57acc001; -#endif + table_base = (void *)private->entries[smp_processor_id()]; + e = get_entry(table_base, private->hook_entry[hook]); /* For return from builtin chain */ - back = get_entry(table_base, table->private->underflow[hook]); + back = get_entry(table_base, private->underflow[hook]); do { IP_NF_ASSERT(e); @@ -384,9 +336,6 @@ ipt_do_table(struct sk_buff **pskb, } } while (!hotdrop); -#ifdef CONFIG_NETFILTER_DEBUG - ((struct ipt_entry *)table_base)->comefrom = 0xdead57ac; -#endif read_unlock_bh(&table->lock); #ifdef DEBUG_ALLOW_ALL @@ -398,145 +347,6 @@ ipt_do_table(struct sk_buff **pskb, #endif } -/* - * These are weird, but module loading must not be done with mutex - * held (since they will register), and we have to have a single - * function to use try_then_request_module(). - */ - -/* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ -static inline struct ipt_table *find_table_lock(const char *name) -{ - struct ipt_table *t; - - if (down_interruptible(&ipt_mutex) != 0) - return ERR_PTR(-EINTR); - - list_for_each_entry(t, &ipt_tables, list) - if (strcmp(t->name, name) == 0 && try_module_get(t->me)) - return t; - up(&ipt_mutex); - return NULL; -} - -/* Find match, grabs ref. Returns ERR_PTR() on error. */ -static inline struct ipt_match *find_match(const char *name, u8 revision) -{ - struct ipt_match *m; - int err = 0; - - if (down_interruptible(&ipt_mutex) != 0) - return ERR_PTR(-EINTR); - - list_for_each_entry(m, &ipt_match, list) { - if (strcmp(m->name, name) == 0) { - if (m->revision == revision) { - if (try_module_get(m->me)) { - up(&ipt_mutex); - return m; - } - } else - err = -EPROTOTYPE; /* Found something. */ - } - } - up(&ipt_mutex); - return ERR_PTR(err); -} - -/* Find target, grabs ref. Returns ERR_PTR() on error. */ -static inline struct ipt_target *find_target(const char *name, u8 revision) -{ - struct ipt_target *t; - int err = 0; - - if (down_interruptible(&ipt_mutex) != 0) - return ERR_PTR(-EINTR); - - list_for_each_entry(t, &ipt_target, list) { - if (strcmp(t->name, name) == 0) { - if (t->revision == revision) { - if (try_module_get(t->me)) { - up(&ipt_mutex); - return t; - } - } else - err = -EPROTOTYPE; /* Found something. */ - } - } - up(&ipt_mutex); - return ERR_PTR(err); -} - -struct ipt_target *ipt_find_target(const char *name, u8 revision) -{ - struct ipt_target *target; - - target = try_then_request_module(find_target(name, revision), - "ipt_%s", name); - if (IS_ERR(target) || !target) - return NULL; - return target; -} - -static int match_revfn(const char *name, u8 revision, int *bestp) -{ - struct ipt_match *m; - int have_rev = 0; - - list_for_each_entry(m, &ipt_match, list) { - if (strcmp(m->name, name) == 0) { - if (m->revision > *bestp) - *bestp = m->revision; - if (m->revision == revision) - have_rev = 1; - } - } - return have_rev; -} - -static int target_revfn(const char *name, u8 revision, int *bestp) -{ - struct ipt_target *t; - int have_rev = 0; - - list_for_each_entry(t, &ipt_target, list) { - if (strcmp(t->name, name) == 0) { - if (t->revision > *bestp) - *bestp = t->revision; - if (t->revision == revision) - have_rev = 1; - } - } - return have_rev; -} - -/* Returns true or false (if no such extension at all) */ -static inline int find_revision(const char *name, u8 revision, - int (*revfn)(const char *, u8, int *), - int *err) -{ - int have_rev, best = -1; - - if (down_interruptible(&ipt_mutex) != 0) { - *err = -EINTR; - return 1; - } - have_rev = revfn(name, revision, &best); - up(&ipt_mutex); - - /* Nothing at all? Return 0 to try loading module. */ - if (best == -1) { - *err = -ENOENT; - return 0; - } - - *err = best; - if (!have_rev) - *err = -EPROTONOSUPPORT; - return 1; -} - - /* All zeroes == unconditional rule. */ static inline int unconditional(const struct ipt_ip *ip) @@ -553,7 +363,7 @@ unconditional(const struct ipt_ip *ip) /* Figures out from what hook each rule can be called: returns 0 if there are loops. Puts hook bitmask in comefrom. */ static int -mark_source_chains(struct ipt_table_info *newinfo, +mark_source_chains(struct xt_table_info *newinfo, unsigned int valid_hooks, void *entry0) { unsigned int hook; @@ -699,7 +509,7 @@ check_match(struct ipt_entry_match *m, { struct ipt_match *match; - match = try_then_request_module(find_match(m->u.user.name, + match = try_then_request_module(xt_find_match(AF_INET, m->u.user.name, m->u.user.revision), "ipt_%s", m->u.user.name); if (IS_ERR(match) || !match) { @@ -744,7 +554,8 @@ check_entry(struct ipt_entry *e, const char *name, unsigned int size, goto cleanup_matches; t = ipt_get_target(e); - target = try_then_request_module(find_target(t->u.user.name, + target = try_then_request_module(xt_find_target(AF_INET, + t->u.user.name, t->u.user.revision), "ipt_%s", t->u.user.name); if (IS_ERR(target) || !target) { @@ -781,7 +592,7 @@ check_entry(struct ipt_entry *e, const char *name, unsigned int size, static inline int check_entry_size_and_hooks(struct ipt_entry *e, - struct ipt_table_info *newinfo, + struct xt_table_info *newinfo, unsigned char *base, unsigned char *limit, const unsigned int *hook_entries, @@ -815,7 +626,7 @@ check_entry_size_and_hooks(struct ipt_entry *e, < 0 (not IPT_RETURN). --RR */ /* Clear counters and comefrom */ - e->counters = ((struct ipt_counters) { 0, 0 }); + e->counters = ((struct xt_counters) { 0, 0 }); e->comefrom = 0; (*i)++; @@ -845,7 +656,7 @@ cleanup_entry(struct ipt_entry *e, unsigned int *i) static int translate_table(const char *name, unsigned int valid_hooks, - struct ipt_table_info *newinfo, + struct xt_table_info *newinfo, void *entry0, unsigned int size, unsigned int number, @@ -922,48 +733,10 @@ translate_table(const char *name, return ret; } -static struct ipt_table_info * -replace_table(struct ipt_table *table, - unsigned int num_counters, - struct ipt_table_info *newinfo, - int *error) -{ - struct ipt_table_info *oldinfo; - -#ifdef CONFIG_NETFILTER_DEBUG - { - int cpu; - - for_each_cpu(cpu) { - struct ipt_entry *table_base = newinfo->entries[cpu]; - if (table_base) - table_base->comefrom = 0xdead57ac; - } - } -#endif - - /* Do the substitution. */ - write_lock_bh(&table->lock); - /* Check inside lock: is the old number correct? */ - if (num_counters != table->private->number) { - duprintf("num_counters != table->private->number (%u/%u)\n", - num_counters, table->private->number); - write_unlock_bh(&table->lock); - *error = -EAGAIN; - return NULL; - } - oldinfo = table->private; - table->private = newinfo; - newinfo->initial_entries = oldinfo->initial_entries; - write_unlock_bh(&table->lock); - - return oldinfo; -} - /* Gets counters. */ static inline int add_entry_to_counter(const struct ipt_entry *e, - struct ipt_counters total[], + struct xt_counters total[], unsigned int *i) { ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); @@ -984,8 +757,8 @@ set_entry_to_counter(const struct ipt_entry *e, } static void -get_counters(const struct ipt_table_info *t, - struct ipt_counters counters[]) +get_counters(const struct xt_table_info *t, + struct xt_counters counters[]) { unsigned int cpu; unsigned int i; @@ -1024,14 +797,15 @@ copy_entries_to_user(unsigned int total_size, { unsigned int off, num, countersize; struct ipt_entry *e; - struct ipt_counters *counters; + struct xt_counters *counters; + struct xt_table_info *private = table->private; int ret = 0; void *loc_cpu_entry; /* We need atomic snapshot of counters: rest doesn't change (other than comefrom, which userspace doesn't care about). */ - countersize = sizeof(struct ipt_counters) * table->private->number; + countersize = sizeof(struct xt_counters) * private->number; counters = vmalloc_node(countersize, numa_node_id()); if (counters == NULL) @@ -1039,14 +813,14 @@ copy_entries_to_user(unsigned int total_size, /* First, sum counters... */ write_lock_bh(&table->lock); - get_counters(table->private, counters); + get_counters(private, counters); write_unlock_bh(&table->lock); /* choose the copy that is on our node/cpu, ... * This choice is lazy (because current thread is * allowed to migrate to another cpu) */ - loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; + loc_cpu_entry = private->entries[raw_smp_processor_id()]; /* ... then copy entire thing ... */ if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { ret = -EFAULT; @@ -1108,74 +882,36 @@ get_entries(const struct ipt_get_entries *entries, int ret; struct ipt_table *t; - t = find_table_lock(entries->name); + t = xt_find_table_lock(AF_INET, entries->name); if (t && !IS_ERR(t)) { + struct xt_table_info *private = t->private; duprintf("t->private->number = %u\n", - t->private->number); - if (entries->size == t->private->size) - ret = copy_entries_to_user(t->private->size, + private->number); + if (entries->size == private->size) + ret = copy_entries_to_user(private->size, t, uptr->entrytable); else { duprintf("get_entries: I've got %u not %u!\n", - t->private->size, + private->size, entries->size); ret = -EINVAL; } module_put(t->me); - up(&ipt_mutex); + xt_table_unlock(t); } else ret = t ? PTR_ERR(t) : -ENOENT; return ret; } -static void free_table_info(struct ipt_table_info *info) -{ - int cpu; - for_each_cpu(cpu) { - if (info->size <= PAGE_SIZE) - kfree(info->entries[cpu]); - else - vfree(info->entries[cpu]); - } - kfree(info); -} - -static struct ipt_table_info *alloc_table_info(unsigned int size) -{ - struct ipt_table_info *newinfo; - int cpu; - - newinfo = kzalloc(sizeof(struct ipt_table_info), GFP_KERNEL); - if (!newinfo) - return NULL; - - newinfo->size = size; - - for_each_cpu(cpu) { - if (size <= PAGE_SIZE) - newinfo->entries[cpu] = kmalloc_node(size, - GFP_KERNEL, - cpu_to_node(cpu)); - else - newinfo->entries[cpu] = vmalloc_node(size, cpu_to_node(cpu)); - if (newinfo->entries[cpu] == 0) { - free_table_info(newinfo); - return NULL; - } - } - - return newinfo; -} - static int do_replace(void __user *user, unsigned int len) { int ret; struct ipt_replace tmp; struct ipt_table *t; - struct ipt_table_info *newinfo, *oldinfo; - struct ipt_counters *counters; + struct xt_table_info *newinfo, *oldinfo; + struct xt_counters *counters; void *loc_cpu_entry, *loc_cpu_old_entry; if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) @@ -1185,11 +921,7 @@ do_replace(void __user *user, unsigned int len) if (len != sizeof(tmp) + tmp.size) return -ENOPROTOOPT; - /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ - if ((SMP_ALIGN(tmp.size) >> PAGE_SHIFT) + 2 > num_physpages) - return -ENOMEM; - - newinfo = alloc_table_info(tmp.size); + newinfo = xt_alloc_table_info(tmp.size); if (!newinfo) return -ENOMEM; @@ -1201,7 +933,7 @@ do_replace(void __user *user, unsigned int len) goto free_newinfo; } - counters = vmalloc(tmp.num_counters * sizeof(struct ipt_counters)); + counters = vmalloc(tmp.num_counters * sizeof(struct xt_counters)); if (!counters) { ret = -ENOMEM; goto free_newinfo; @@ -1215,7 +947,7 @@ do_replace(void __user *user, unsigned int len) duprintf("ip_tables: Translated table\n"); - t = try_then_request_module(find_table_lock(tmp.name), + t = try_then_request_module(xt_find_table_lock(AF_INET, tmp.name), "iptable_%s", tmp.name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; @@ -1230,7 +962,7 @@ do_replace(void __user *user, unsigned int len) goto put_module; } - oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret); + oldinfo = xt_replace_table(t, tmp.num_counters, newinfo, &ret); if (!oldinfo) goto put_module; @@ -1249,23 +981,23 @@ do_replace(void __user *user, unsigned int len) /* Decrease module usage counts and free resource */ loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; IPT_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL); - free_table_info(oldinfo); + xt_free_table_info(oldinfo); if (copy_to_user(tmp.counters, counters, - sizeof(struct ipt_counters) * tmp.num_counters) != 0) + sizeof(struct xt_counters) * tmp.num_counters) != 0) ret = -EFAULT; vfree(counters); - up(&ipt_mutex); + xt_table_unlock(t); return ret; put_module: module_put(t->me); - up(&ipt_mutex); + xt_table_unlock(t); free_newinfo_counters_untrans: IPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry,NULL); free_newinfo_counters: vfree(counters); free_newinfo: - free_table_info(newinfo); + xt_free_table_info(newinfo); return ret; } @@ -1273,7 +1005,7 @@ do_replace(void __user *user, unsigned int len) * and everything is OK. */ static inline int add_counter_to_entry(struct ipt_entry *e, - const struct ipt_counters addme[], + const struct xt_counters addme[], unsigned int *i) { #if 0 @@ -1295,15 +1027,16 @@ static int do_add_counters(void __user *user, unsigned int len) { unsigned int i; - struct ipt_counters_info tmp, *paddc; + struct xt_counters_info tmp, *paddc; struct ipt_table *t; + struct xt_table_info *private; int ret = 0; void *loc_cpu_entry; if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) return -EFAULT; - if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct ipt_counters)) + if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct xt_counters)) return -EINVAL; paddc = vmalloc_node(len, numa_node_id()); @@ -1315,29 +1048,30 @@ do_add_counters(void __user *user, unsigned int len) goto free; } - t = find_table_lock(tmp.name); + t = xt_find_table_lock(AF_INET, tmp.name); if (!t || IS_ERR(t)) { ret = t ? PTR_ERR(t) : -ENOENT; goto free; } write_lock_bh(&t->lock); - if (t->private->number != paddc->num_counters) { + private = t->private; + if (private->number != paddc->num_counters) { ret = -EINVAL; goto unlock_up_free; } i = 0; /* Choose the copy that is on our node */ - loc_cpu_entry = t->private->entries[raw_smp_processor_id()]; + loc_cpu_entry = private->entries[raw_smp_processor_id()]; IPT_ENTRY_ITERATE(loc_cpu_entry, - t->private->size, + private->size, add_counter_to_entry, paddc->counters, &i); unlock_up_free: write_unlock_bh(&t->lock); - up(&ipt_mutex); + xt_table_unlock(t); module_put(t->me); free: vfree(paddc); @@ -1396,25 +1130,26 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) } name[IPT_TABLE_MAXNAMELEN-1] = '\0'; - t = try_then_request_module(find_table_lock(name), + t = try_then_request_module(xt_find_table_lock(AF_INET, name), "iptable_%s", name); if (t && !IS_ERR(t)) { struct ipt_getinfo info; + struct xt_table_info *private = t->private; info.valid_hooks = t->valid_hooks; - memcpy(info.hook_entry, t->private->hook_entry, + memcpy(info.hook_entry, private->hook_entry, sizeof(info.hook_entry)); - memcpy(info.underflow, t->private->underflow, + memcpy(info.underflow, private->underflow, sizeof(info.underflow)); - info.num_entries = t->private->number; - info.size = t->private->size; + info.num_entries = private->number; + info.size = private->size; memcpy(info.name, name, sizeof(info.name)); if (copy_to_user(user, &info, *len) != 0) ret = -EFAULT; else ret = 0; - up(&ipt_mutex); + xt_table_unlock(t); module_put(t->me); } else ret = t ? PTR_ERR(t) : -ENOENT; @@ -1441,7 +1176,7 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) case IPT_SO_GET_REVISION_MATCH: case IPT_SO_GET_REVISION_TARGET: { struct ipt_get_revision rev; - int (*revfn)(const char *, u8, int *); + int target; if (*len != sizeof(rev)) { ret = -EINVAL; @@ -1453,12 +1188,13 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) } if (cmd == IPT_SO_GET_REVISION_TARGET) - revfn = target_revfn; + target = 1; else - revfn = match_revfn; + target = 0; - try_then_request_module(find_revision(rev.name, rev.revision, - revfn, &ret), + try_then_request_module(xt_find_revision(AF_INET, rev.name, + rev.revision, + target, &ret), "ipt_%s", rev.name); break; } @@ -1471,60 +1207,15 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) return ret; } -/* Registration hooks for targets. */ -int -ipt_register_target(struct ipt_target *target) +int ipt_register_table(struct xt_table *table, const struct ipt_replace *repl) { int ret; - - ret = down_interruptible(&ipt_mutex); - if (ret != 0) - return ret; - list_add(&target->list, &ipt_target); - up(&ipt_mutex); - return ret; -} - -void -ipt_unregister_target(struct ipt_target *target) -{ - down(&ipt_mutex); - LIST_DELETE(&ipt_target, target); - up(&ipt_mutex); -} - -int -ipt_register_match(struct ipt_match *match) -{ - int ret; - - ret = down_interruptible(&ipt_mutex); - if (ret != 0) - return ret; - - list_add(&match->list, &ipt_match); - up(&ipt_mutex); - - return ret; -} - -void -ipt_unregister_match(struct ipt_match *match) -{ - down(&ipt_mutex); - LIST_DELETE(&ipt_match, match); - up(&ipt_mutex); -} - -int ipt_register_table(struct ipt_table *table, const struct ipt_replace *repl) -{ - int ret; - struct ipt_table_info *newinfo; - static struct ipt_table_info bootstrap + struct xt_table_info *newinfo; + static struct xt_table_info bootstrap = { 0, 0, 0, { 0 }, { 0 }, { } }; void *loc_cpu_entry; - newinfo = alloc_table_info(repl->size); + newinfo = xt_alloc_table_info(repl->size); if (!newinfo) return -ENOMEM; @@ -1540,246 +1231,29 @@ int ipt_register_table(struct ipt_table *table, const struct ipt_replace *repl) repl->hook_entry, repl->underflow); if (ret != 0) { - free_table_info(newinfo); + xt_free_table_info(newinfo); return ret; } - ret = down_interruptible(&ipt_mutex); - if (ret != 0) { - free_table_info(newinfo); + if (xt_register_table(table, &bootstrap, newinfo) != 0) { + xt_free_table_info(newinfo); return ret; } - /* Don't autoload: we'd eat our tail... */ - if (list_named_find(&ipt_tables, table->name)) { - ret = -EEXIST; - goto free_unlock; - } - - /* Simplifies replace_table code. */ - table->private = &bootstrap; - if (!replace_table(table, 0, newinfo, &ret)) - goto free_unlock; - - duprintf("table->private->number = %u\n", - table->private->number); - - /* save number of initial entries */ - table->private->initial_entries = table->private->number; - - rwlock_init(&table->lock); - list_prepend(&ipt_tables, table); - - unlock: - up(&ipt_mutex); - return ret; - - free_unlock: - free_table_info(newinfo); - goto unlock; + return 0; } void ipt_unregister_table(struct ipt_table *table) { + struct xt_table_info *private; void *loc_cpu_entry; - down(&ipt_mutex); - LIST_DELETE(&ipt_tables, table); - up(&ipt_mutex); + private = xt_unregister_table(table); /* Decrease module usage counts and free resources */ - loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; - IPT_ENTRY_ITERATE(loc_cpu_entry, table->private->size, - cleanup_entry, NULL); - free_table_info(table->private); -} - -/* Returns 1 if the port is matched by the range, 0 otherwise */ -static inline int -port_match(u_int16_t min, u_int16_t max, u_int16_t port, int invert) -{ - int ret; - - ret = (port >= min && port <= max) ^ invert; - return ret; -} - -static int -tcp_find_option(u_int8_t option, - const struct sk_buff *skb, - unsigned int optlen, - int invert, - int *hotdrop) -{ - /* tcp.doff is only 4 bits, ie. max 15 * 4 bytes */ - u_int8_t _opt[60 - sizeof(struct tcphdr)], *op; - unsigned int i; - - duprintf("tcp_match: finding option\n"); - - if (!optlen) - return invert; - - /* If we don't have the whole header, drop packet. */ - op = skb_header_pointer(skb, - skb->nh.iph->ihl*4 + sizeof(struct tcphdr), - optlen, _opt); - if (op == NULL) { - *hotdrop = 1; - return 0; - } - - for (i = 0; i < optlen; ) { - if (op[i] == option) return !invert; - if (op[i] < 2) i++; - else i += op[i+1]?:1; - } - - return invert; -} - -static int -tcp_match(const struct sk_buff *skb, - const struct net_device *in, - const struct net_device *out, - const void *matchinfo, - int offset, - int *hotdrop) -{ - struct tcphdr _tcph, *th; - const struct ipt_tcp *tcpinfo = matchinfo; - - if (offset) { - /* To quote Alan: - - Don't allow a fragment of TCP 8 bytes in. Nobody normal - causes this. Its a cracker trying to break in by doing a - flag overwrite to pass the direction checks. - */ - if (offset == 1) { - duprintf("Dropping evil TCP offset=1 frag.\n"); - *hotdrop = 1; - } - /* Must not be a fragment. */ - return 0; - } - -#define FWINVTCP(bool,invflg) ((bool) ^ !!(tcpinfo->invflags & invflg)) - - th = skb_header_pointer(skb, skb->nh.iph->ihl*4, - sizeof(_tcph), &_tcph); - if (th == NULL) { - /* We've been asked to examine this packet, and we - can't. Hence, no choice but to drop. */ - duprintf("Dropping evil TCP offset=0 tinygram.\n"); - *hotdrop = 1; - return 0; - } - - if (!port_match(tcpinfo->spts[0], tcpinfo->spts[1], - ntohs(th->source), - !!(tcpinfo->invflags & IPT_TCP_INV_SRCPT))) - return 0; - if (!port_match(tcpinfo->dpts[0], tcpinfo->dpts[1], - ntohs(th->dest), - !!(tcpinfo->invflags & IPT_TCP_INV_DSTPT))) - return 0; - if (!FWINVTCP((((unsigned char *)th)[13] & tcpinfo->flg_mask) - == tcpinfo->flg_cmp, - IPT_TCP_INV_FLAGS)) - return 0; - if (tcpinfo->option) { - if (th->doff * 4 < sizeof(_tcph)) { - *hotdrop = 1; - return 0; - } - if (!tcp_find_option(tcpinfo->option, skb, - th->doff*4 - sizeof(_tcph), - tcpinfo->invflags & IPT_TCP_INV_OPTION, - hotdrop)) - return 0; - } - return 1; -} - -/* Called when user tries to insert an entry of this type. */ -static int -tcp_checkentry(const char *tablename, - const struct ipt_ip *ip, - void *matchinfo, - unsigned int matchsize, - unsigned int hook_mask) -{ - const struct ipt_tcp *tcpinfo = matchinfo; - - /* Must specify proto == TCP, and no unknown invflags */ - return ip->proto == IPPROTO_TCP - && !(ip->invflags & IPT_INV_PROTO) - && matchsize == IPT_ALIGN(sizeof(struct ipt_tcp)) - && !(tcpinfo->invflags & ~IPT_TCP_INV_MASK); -} - -static int -udp_match(const struct sk_buff *skb, - const struct net_device *in, - const struct net_device *out, - const void *matchinfo, - int offset, - int *hotdrop) -{ - struct udphdr _udph, *uh; - const struct ipt_udp *udpinfo = matchinfo; - - /* Must not be a fragment. */ - if (offset) - return 0; - - uh = skb_header_pointer(skb, skb->nh.iph->ihl*4, - sizeof(_udph), &_udph); - if (uh == NULL) { - /* We've been asked to examine this packet, and we - can't. Hence, no choice but to drop. */ - duprintf("Dropping evil UDP tinygram.\n"); - *hotdrop = 1; - return 0; - } - - return port_match(udpinfo->spts[0], udpinfo->spts[1], - ntohs(uh->source), - !!(udpinfo->invflags & IPT_UDP_INV_SRCPT)) - && port_match(udpinfo->dpts[0], udpinfo->dpts[1], - ntohs(uh->dest), - !!(udpinfo->invflags & IPT_UDP_INV_DSTPT)); -} - -/* Called when user tries to insert an entry of this type. */ -static int -udp_checkentry(const char *tablename, - const struct ipt_ip *ip, - void *matchinfo, - unsigned int matchinfosize, - unsigned int hook_mask) -{ - const struct ipt_udp *udpinfo = matchinfo; - - /* Must specify proto == UDP, and no unknown invflags */ - if (ip->proto != IPPROTO_UDP || (ip->invflags & IPT_INV_PROTO)) { - duprintf("ipt_udp: Protocol %u != %u\n", ip->proto, - IPPROTO_UDP); - return 0; - } - if (matchinfosize != IPT_ALIGN(sizeof(struct ipt_udp))) { - duprintf("ipt_udp: matchsize %u != %u\n", - matchinfosize, IPT_ALIGN(sizeof(struct ipt_udp))); - return 0; - } - if (udpinfo->invflags & ~IPT_UDP_INV_MASK) { - duprintf("ipt_udp: unknown flags %X\n", - udpinfo->invflags); - return 0; - } - - return 1; + loc_cpu_entry = private->entries[raw_smp_processor_id()]; + IPT_ENTRY_ITERATE(loc_cpu_entry, private->size, cleanup_entry, NULL); + xt_free_table_info(private); } /* Returns 1 if the type and code is matched by the range, 0 otherwise */ @@ -1798,6 +1272,7 @@ icmp_match(const struct sk_buff *skb, const struct net_device *out, const void *matchinfo, int offset, + unsigned int protoff, int *hotdrop) { struct icmphdr _icmph, *ic; @@ -1807,8 +1282,7 @@ icmp_match(const struct sk_buff *skb, if (offset) return 0; - ic = skb_header_pointer(skb, skb->nh.iph->ihl*4, - sizeof(_icmph), &_icmph); + ic = skb_header_pointer(skb, protoff, sizeof(_icmph), &_icmph); if (ic == NULL) { /* We've been asked to examine this packet, and we * can't. Hence, no choice but to drop. @@ -1828,11 +1302,12 @@ icmp_match(const struct sk_buff *skb, /* Called when user tries to insert an entry of this type. */ static int icmp_checkentry(const char *tablename, - const struct ipt_ip *ip, + const void *info, void *matchinfo, unsigned int matchsize, unsigned int hook_mask) { + const struct ipt_ip *ip = info; const struct ipt_icmp *icmpinfo = matchinfo; /* Must specify proto == ICMP, and no unknown invflags */ @@ -1862,123 +1337,22 @@ static struct nf_sockopt_ops ipt_sockopts = { .get = do_ipt_get_ctl, }; -static struct ipt_match tcp_matchstruct = { - .name = "tcp", - .match = &tcp_match, - .checkentry = &tcp_checkentry, -}; - -static struct ipt_match udp_matchstruct = { - .name = "udp", - .match = &udp_match, - .checkentry = &udp_checkentry, -}; - static struct ipt_match icmp_matchstruct = { .name = "icmp", .match = &icmp_match, .checkentry = &icmp_checkentry, }; -#ifdef CONFIG_PROC_FS -static inline int print_name(const char *i, - off_t start_offset, char *buffer, int length, - off_t *pos, unsigned int *count) -{ - if ((*count)++ >= start_offset) { - unsigned int namelen; - - namelen = sprintf(buffer + *pos, "%s\n", - i + sizeof(struct list_head)); - if (*pos + namelen > length) { - /* Stop iterating */ - return 1; - } - *pos += namelen; - } - return 0; -} - -static inline int print_target(const struct ipt_target *t, - off_t start_offset, char *buffer, int length, - off_t *pos, unsigned int *count) -{ - if (t == &ipt_standard_target || t == &ipt_error_target) - return 0; - return print_name((char *)t, start_offset, buffer, length, pos, count); -} - -static int ipt_get_tables(char *buffer, char **start, off_t offset, int length) -{ - off_t pos = 0; - unsigned int count = 0; - - if (down_interruptible(&ipt_mutex) != 0) - return 0; - - LIST_FIND(&ipt_tables, print_name, void *, - offset, buffer, length, &pos, &count); - - up(&ipt_mutex); - - /* `start' hack - see fs/proc/generic.c line ~105 */ - *start=(char *)((unsigned long)count-offset); - return pos; -} - -static int ipt_get_targets(char *buffer, char **start, off_t offset, int length) -{ - off_t pos = 0; - unsigned int count = 0; - - if (down_interruptible(&ipt_mutex) != 0) - return 0; - - LIST_FIND(&ipt_target, print_target, struct ipt_target *, - offset, buffer, length, &pos, &count); - - up(&ipt_mutex); - - *start = (char *)((unsigned long)count - offset); - return pos; -} - -static int ipt_get_matches(char *buffer, char **start, off_t offset, int length) -{ - off_t pos = 0; - unsigned int count = 0; - - if (down_interruptible(&ipt_mutex) != 0) - return 0; - - LIST_FIND(&ipt_match, print_name, void *, - offset, buffer, length, &pos, &count); - - up(&ipt_mutex); - - *start = (char *)((unsigned long)count - offset); - return pos; -} - -static const struct { char *name; get_info_t *get_info; } ipt_proc_entry[] = -{ { "ip_tables_names", ipt_get_tables }, - { "ip_tables_targets", ipt_get_targets }, - { "ip_tables_matches", ipt_get_matches }, - { NULL, NULL} }; -#endif /*CONFIG_PROC_FS*/ - static int __init init(void) { int ret; + xt_proto_init(AF_INET); + /* Noone else will be downing sem now, so we won't sleep */ - down(&ipt_mutex); - list_append(&ipt_target, &ipt_standard_target); - list_append(&ipt_target, &ipt_error_target); - list_append(&ipt_match, &tcp_matchstruct); - list_append(&ipt_match, &udp_matchstruct); - list_append(&ipt_match, &icmp_matchstruct); - up(&ipt_mutex); + xt_register_target(AF_INET, &ipt_standard_target); + xt_register_target(AF_INET, &ipt_error_target); + xt_register_match(AF_INET, &icmp_matchstruct); /* Register setsockopt */ ret = nf_register_sockopt(&ipt_sockopts); @@ -1987,49 +1361,23 @@ static int __init init(void) return ret; } -#ifdef CONFIG_PROC_FS - { - struct proc_dir_entry *proc; - int i; - - for (i = 0; ipt_proc_entry[i].name; i++) { - proc = proc_net_create(ipt_proc_entry[i].name, 0, - ipt_proc_entry[i].get_info); - if (!proc) { - while (--i >= 0) - proc_net_remove(ipt_proc_entry[i].name); - nf_unregister_sockopt(&ipt_sockopts); - return -ENOMEM; - } - proc->owner = THIS_MODULE; - } - } -#endif - - printk("ip_tables: (C) 2000-2002 Netfilter core team\n"); + printk("ip_tables: (C) 2000-2006 Netfilter Core Team\n"); return 0; } static void __exit fini(void) { nf_unregister_sockopt(&ipt_sockopts); -#ifdef CONFIG_PROC_FS - { - int i; - for (i = 0; ipt_proc_entry[i].name; i++) - proc_net_remove(ipt_proc_entry[i].name); - } -#endif + + xt_unregister_match(AF_INET, &icmp_matchstruct); + xt_unregister_target(AF_INET, &ipt_error_target); + xt_unregister_target(AF_INET, &ipt_standard_target); + + xt_proto_fini(AF_INET); } EXPORT_SYMBOL(ipt_register_table); EXPORT_SYMBOL(ipt_unregister_table); -EXPORT_SYMBOL(ipt_register_match); -EXPORT_SYMBOL(ipt_unregister_match); EXPORT_SYMBOL(ipt_do_table); -EXPORT_SYMBOL(ipt_register_target); -EXPORT_SYMBOL(ipt_unregister_target); -EXPORT_SYMBOL(ipt_find_target); - module_init(init); module_exit(fini); |