| /* |
| * Format of an ARP firewall descriptor |
| * |
| * src, tgt, src_mask, tgt_mask, arpop, arpop_mask are always stored in |
| * network byte order. |
| * flags are stored in host byte order (of course). |
| */ |
| |
| #ifndef _ARPTABLES_H |
| #define _ARPTABLES_H |
| |
| #ifdef __KERNEL__ |
| #include <linux/if.h> |
| #include <linux/types.h> |
| #include <linux/in.h> |
| #include <linux/if_arp.h> |
| #include <linux/skbuff.h> |
| #endif |
| #include <linux/compiler.h> |
| #include <linux/netfilter_arp.h> |
| |
| #include <linux/netfilter/x_tables.h> |
| |
| #define ARPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN |
| #define ARPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN |
| #define arpt_target xt_target |
| #define arpt_table xt_table |
| |
| #define ARPT_DEV_ADDR_LEN_MAX 16 |
| |
| struct arpt_devaddr_info { |
| char addr[ARPT_DEV_ADDR_LEN_MAX]; |
| char mask[ARPT_DEV_ADDR_LEN_MAX]; |
| }; |
| |
| /* Yes, Virginia, you have to zero the padding. */ |
| struct arpt_arp { |
| /* Source and target IP addr */ |
| struct in_addr src, tgt; |
| /* Mask for src and target IP addr */ |
| struct in_addr smsk, tmsk; |
| |
| /* Device hw address length, src+target device addresses */ |
| u_int8_t arhln, arhln_mask; |
| struct arpt_devaddr_info src_devaddr; |
| struct arpt_devaddr_info tgt_devaddr; |
| |
| /* ARP operation code. */ |
| u_int16_t arpop, arpop_mask; |
| |
| /* ARP hardware address and protocol address format. */ |
| u_int16_t arhrd, arhrd_mask; |
| u_int16_t arpro, arpro_mask; |
| |
| /* The protocol address length is only accepted if it is 4 |
| * so there is no use in offering a way to do filtering on it. |
| */ |
| |
| char iniface[IFNAMSIZ], outiface[IFNAMSIZ]; |
| unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ]; |
| |
| /* Flags word */ |
| u_int8_t flags; |
| /* Inverse flags */ |
| u_int16_t invflags; |
| }; |
| |
| #define arpt_entry_target xt_entry_target |
| #define arpt_standard_target xt_standard_target |
| |
| /* Values for "flag" field in struct arpt_ip (general arp structure). |
| * No flags defined yet. |
| */ |
| #define ARPT_F_MASK 0x00 /* All possible flag bits mask. */ |
| |
| /* Values for "inv" field in struct arpt_arp. */ |
| #define ARPT_INV_VIA_IN 0x0001 /* Invert the sense of IN IFACE. */ |
| #define ARPT_INV_VIA_OUT 0x0002 /* Invert the sense of OUT IFACE */ |
| #define ARPT_INV_SRCIP 0x0004 /* Invert the sense of SRC IP. */ |
| #define ARPT_INV_TGTIP 0x0008 /* Invert the sense of TGT IP. */ |
| #define ARPT_INV_SRCDEVADDR 0x0010 /* Invert the sense of SRC DEV ADDR. */ |
| #define ARPT_INV_TGTDEVADDR 0x0020 /* Invert the sense of TGT DEV ADDR. */ |
| #define ARPT_INV_ARPOP 0x0040 /* Invert the sense of ARP OP. */ |
| #define ARPT_INV_ARPHRD 0x0080 /* Invert the sense of ARP HRD. */ |
| #define ARPT_INV_ARPPRO 0x0100 /* Invert the sense of ARP PRO. */ |
| #define ARPT_INV_ARPHLN 0x0200 /* Invert the sense of ARP HLN. */ |
| #define ARPT_INV_MASK 0x03FF /* All possible flag bits mask. */ |
| |
| /* This structure defines each of the firewall rules. Consists of 3 |
| parts which are 1) general ARP header stuff 2) match specific |
| stuff 3) the target to perform if the rule matches */ |
| struct arpt_entry |
| { |
| struct arpt_arp arp; |
| |
| /* Size of arpt_entry + matches */ |
| u_int16_t target_offset; |
| /* Size of arpt_entry + matches + target */ |
| u_int16_t next_offset; |
| |
| /* Back pointer */ |
| unsigned int comefrom; |
| |
| /* Packet and byte counters. */ |
| struct xt_counters counters; |
| |
| /* The matches (if any), then the target. */ |
| unsigned char elems[0]; |
| }; |
| |
| /* |
| * 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 ARPT_CTL_OFFSET 32 |
| #define ARPT_BASE_CTL (XT_BASE_CTL+ARPT_CTL_OFFSET) |
| |
| #define ARPT_SO_SET_REPLACE (XT_SO_SET_REPLACE+ARPT_CTL_OFFSET) |
| #define ARPT_SO_SET_ADD_COUNTERS (XT_SO_SET_ADD_COUNTERS+ARPT_CTL_OFFSET) |
| #define ARPT_SO_SET_MAX (XT_SO_SET_MAX+ARPT_CTL_OFFSET) |
| |
| #define ARPT_SO_GET_INFO (XT_SO_GET_INFO+ARPT_CTL_OFFSET) |
| #define ARPT_SO_GET_ENTRIES (XT_SO_GET_ENTRIES+ARPT_CTL_OFFSET) |
| /* #define ARPT_SO_GET_REVISION_MATCH XT_SO_GET_REVISION_MATCH */ |
| #define ARPT_SO_GET_REVISION_TARGET (XT_SO_GET_REVISION_TARGET+ARPT_CTL_OFFSET) |
| #define ARPT_SO_GET_MAX (XT_SO_GET_REVISION_TARGET+ARPT_CTL_OFFSET) |
| |
| /* CONTINUE verdict for targets */ |
| #define ARPT_CONTINUE XT_CONTINUE |
| |
| /* For standard target */ |
| #define ARPT_RETURN XT_RETURN |
| |
| /* The argument to ARPT_SO_GET_INFO */ |
| struct arpt_getinfo |
| { |
| /* Which table: caller fills this in. */ |
| char name[ARPT_TABLE_MAXNAMELEN]; |
| |
| /* Kernel fills these in. */ |
| /* Which hook entry points are valid: bitmask */ |
| unsigned int valid_hooks; |
| |
| /* Hook entry points: one per netfilter hook. */ |
| unsigned int hook_entry[NF_ARP_NUMHOOKS]; |
| |
| /* Underflow points. */ |
| unsigned int underflow[NF_ARP_NUMHOOKS]; |
| |
| /* Number of entries */ |
| unsigned int num_entries; |
| |
| /* Size of entries. */ |
| unsigned int size; |
| }; |
| |
| /* The argument to ARPT_SO_SET_REPLACE. */ |
| struct arpt_replace |
| { |
| /* Which table. */ |
| char name[ARPT_TABLE_MAXNAMELEN]; |
| |
| /* Which hook entry points are valid: bitmask. You can't |
| change this. */ |
| unsigned int valid_hooks; |
| |
| /* Number of entries */ |
| unsigned int num_entries; |
| |
| /* Total size of new entries */ |
| unsigned int size; |
| |
| /* Hook entry points. */ |
| unsigned int hook_entry[NF_ARP_NUMHOOKS]; |
| |
| /* Underflow points. */ |
| unsigned int underflow[NF_ARP_NUMHOOKS]; |
| |
| /* Information about old entries: */ |
| /* Number of counters (must be equal to current number of entries). */ |
| unsigned int num_counters; |
| /* The old entries' counters. */ |
| struct xt_counters __user *counters; |
| |
| /* The entries (hang off end: not really an array). */ |
| struct arpt_entry entries[0]; |
| }; |
| |
| /* The argument to ARPT_SO_ADD_COUNTERS. */ |
| #define arpt_counters_info xt_counters_info |
| |
| /* The argument to ARPT_SO_GET_ENTRIES. */ |
| struct arpt_get_entries |
| { |
| /* Which table: user fills this in. */ |
| char name[ARPT_TABLE_MAXNAMELEN]; |
| |
| /* User fills this in: total entry size. */ |
| unsigned int size; |
| |
| /* The entries. */ |
| struct arpt_entry entrytable[0]; |
| }; |
| |
| /* Standard return verdict, or do jump. */ |
| #define ARPT_STANDARD_TARGET XT_STANDARD_TARGET |
| /* Error verdict. */ |
| #define ARPT_ERROR_TARGET XT_ERROR_TARGET |
| |
| /* Helper functions */ |
| static __inline__ struct arpt_entry_target *arpt_get_target(struct arpt_entry *e) |
| { |
| return (void *)e + e->target_offset; |
| } |
| |
| /* fn returns 0 to continue iteration */ |
| #define ARPT_ENTRY_ITERATE(entries, size, fn, args...) \ |
| ({ \ |
| unsigned int __i; \ |
| int __ret = 0; \ |
| struct arpt_entry *__entry; \ |
| \ |
| for (__i = 0; __i < (size); __i += __entry->next_offset) { \ |
| __entry = (void *)(entries) + __i; \ |
| \ |
| __ret = fn(__entry , ## args); \ |
| if (__ret != 0) \ |
| break; \ |
| } \ |
| __ret; \ |
| }) |
| |
| /* |
| * Main firewall chains definitions and global var's definitions. |
| */ |
| #ifdef __KERNEL__ |
| |
| #define arpt_register_target(tgt) \ |
| ({ (tgt)->family = NF_ARP; \ |
| xt_register_target(tgt); }) |
| #define arpt_unregister_target(tgt) xt_unregister_target(tgt) |
| |
| extern int arpt_register_table(struct arpt_table *table, |
| const struct arpt_replace *repl); |
| extern void arpt_unregister_table(struct arpt_table *table); |
| extern unsigned int arpt_do_table(struct sk_buff **pskb, |
| unsigned int hook, |
| const struct net_device *in, |
| const struct net_device *out, |
| struct arpt_table *table, |
| void *userdata); |
| |
| #define ARPT_ALIGN(s) (((s) + (__alignof__(struct arpt_entry)-1)) & ~(__alignof__(struct arpt_entry)-1)) |
| #endif /*__KERNEL__*/ |
| #endif /* _ARPTABLES_H */ |