From 2e4e6a17af35be359cc8f1c924f8f198fbd478cc Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Thu, 12 Jan 2006 13:30:04 -0800 Subject: [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 Signed-off-by: David S. Miller --- include/linux/netfilter/x_tables.h | 224 +++++++++++++++++++++++++++++++++++++ 1 file changed, 224 insertions(+) create mode 100644 include/linux/netfilter/x_tables.h (limited to 'include/linux/netfilter/x_tables.h') diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h new file mode 100644 index 00000000000..472f0483480 --- /dev/null +++ b/include/linux/netfilter/x_tables.h @@ -0,0 +1,224 @@ +#ifndef _X_TABLES_H +#define _X_TABLES_H + +#define XT_FUNCTION_MAXNAMELEN 30 +#define XT_TABLE_MAXNAMELEN 32 + +/* The argument to IPT_SO_GET_REVISION_*. Returns highest revision + * kernel supports, if >= revision. */ +struct xt_get_revision +{ + char name[XT_FUNCTION_MAXNAMELEN-1]; + + u_int8_t revision; +}; + +/* CONTINUE verdict for targets */ +#define XT_CONTINUE 0xFFFFFFFF + +/* For standard target */ +#define XT_RETURN (-NF_REPEAT - 1) + +#define XT_ALIGN(s) (((s) + (__alignof__(void *)-1)) & ~(__alignof__(void *)-1)) + +/* Standard return verdict, or do jump. */ +#define XT_STANDARD_TARGET "" +/* Error verdict. */ +#define XT_ERROR_TARGET "ERROR" + +/* + * New IP firewall options for [gs]etsockopt at the RAW IP level. + * Unlike BSD Linux inherits IP options so you don't have to use a raw + * socket for this. Instead we check rights in the calls. */ +#define XT_BASE_CTL 64 /* base for firewall socket options */ + +#define XT_SO_SET_REPLACE (XT_BASE_CTL) +#define XT_SO_SET_ADD_COUNTERS (XT_BASE_CTL + 1) +#define XT_SO_SET_MAX XT_SO_SET_ADD_COUNTERS + +#define XT_SO_GET_INFO (XT_BASE_CTL) +#define XT_SO_GET_ENTRIES (XT_BASE_CTL + 1) +#define XT_SO_GET_REVISION_MATCH (XT_BASE_CTL + 2) +#define XT_SO_GET_REVISION_TARGET (XT_BASE_CTL + 3) +#define XT_SO_GET_MAX XT_SO_GET_REVISION_TARGET + +#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) + +struct xt_counters +{ + u_int64_t pcnt, bcnt; /* Packet and byte counters */ +}; + +/* The argument to IPT_SO_ADD_COUNTERS. */ +struct xt_counters_info +{ + /* Which table. */ + char name[XT_TABLE_MAXNAMELEN]; + + unsigned int num_counters; + + /* The counters (actually `number' of these). */ + struct xt_counters counters[0]; +}; + +#define XT_INV_PROTO 0x40 /* Invert the sense of PROTO. */ + +#ifdef __KERNEL__ + +#include + +#define ASSERT_READ_LOCK(x) +#define ASSERT_WRITE_LOCK(x) +#include + +struct xt_match +{ + struct list_head list; + + const char name[XT_FUNCTION_MAXNAMELEN-1]; + + u_int8_t revision; + + /* Return true or false: return FALSE and set *hotdrop = 1 to + force immediate packet drop. */ + /* Arguments changed since 2.6.9, as this must now handle + non-linear skb, using skb_header_pointer and + skb_ip_make_writable. */ + int (*match)(const struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + const void *matchinfo, + int offset, + unsigned int protoff, + int *hotdrop); + + /* Called when user tries to insert an entry of this type. */ + /* Should return true or false. */ + int (*checkentry)(const char *tablename, + const void *ip, + void *matchinfo, + unsigned int matchinfosize, + unsigned int hook_mask); + + /* Called when entry of this type deleted. */ + void (*destroy)(void *matchinfo, unsigned int matchinfosize); + + /* Set this to THIS_MODULE if you are a module, otherwise NULL */ + struct module *me; +}; + +/* Registration hooks for targets. */ +struct xt_target +{ + struct list_head list; + + const char name[XT_FUNCTION_MAXNAMELEN-1]; + + u_int8_t revision; + + /* Returns verdict. Argument order changed since 2.6.9, as this + must now handle non-linear skbs, using skb_copy_bits and + skb_ip_make_writable. */ + unsigned int (*target)(struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + unsigned int hooknum, + const void *targinfo, + void *userdata); + + /* Called when user tries to insert an entry of this type: + hook_mask is a bitmask of hooks from which it can be + called. */ + /* Should return true or false. */ + int (*checkentry)(const char *tablename, + const void *entry, + void *targinfo, + unsigned int targinfosize, + unsigned int hook_mask); + + /* Called when entry of this type deleted. */ + void (*destroy)(void *targinfo, unsigned int targinfosize); + + /* Set this to THIS_MODULE if you are a module, otherwise NULL */ + struct module *me; +}; + +/* Furniture shopping... */ +struct xt_table +{ + struct list_head list; + + /* A unique name... */ + char name[XT_TABLE_MAXNAMELEN]; + + /* What hooks you will enter on */ + unsigned int valid_hooks; + + /* Lock for the curtain */ + rwlock_t lock; + + /* Man behind the curtain... */ + //struct ip6t_table_info *private; + void *private; + + /* Set this to THIS_MODULE if you are a module, otherwise NULL */ + struct module *me; + + int af; /* address/protocol family */ +}; + +#include + +/* The table itself */ +struct xt_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 */ + char *entries[NR_CPUS]; +}; + +extern int xt_register_target(int af, struct xt_target *target); +extern void xt_unregister_target(int af, struct xt_target *target); +extern int xt_register_match(int af, struct xt_match *target); +extern void xt_unregister_match(int af, struct xt_match *target); + +extern int xt_register_table(struct xt_table *table, + struct xt_table_info *bootstrap, + struct xt_table_info *newinfo); +extern void *xt_unregister_table(struct xt_table *table); + +extern struct xt_table_info *xt_replace_table(struct xt_table *table, + unsigned int num_counters, + struct xt_table_info *newinfo, + int *error); + +extern struct xt_match *xt_find_match(int af, const char *name, u8 revision); +extern struct xt_target *xt_find_target(int af, const char *name, u8 revision); +extern struct xt_target *xt_request_find_target(int af, const char *name, + u8 revision); +extern int xt_find_revision(int af, const char *name, u8 revision, int target, + int *err); + +extern struct xt_table *xt_find_table_lock(int af, const char *name); +extern void xt_table_unlock(struct xt_table *t); + +extern int xt_proto_init(int af); +extern void xt_proto_fini(int af); + +extern struct xt_table_info *xt_alloc_table_info(unsigned int size); +extern void xt_free_table_info(struct xt_table_info *info); + +#endif /* __KERNEL__ */ + +#endif /* _X_TABLES_H */ -- cgit v1.2.3