/* * 25-Jul-1998 Major changes to allow for ip chain table * * 3-Jan-2000 Named tables to allow packet selection for different uses. */ /* * Format of an IP firewall descriptor * * src, dst, src_mask, dst_mask are always stored in network byte order. * flags are stored in host byte order (of course). * Port numbers are stored in HOST byte order. */ #ifndef _IPTABLES_H #define _IPTABLES_H #include #include #define IPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN #define IPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN #define ipt_match xt_match #define ipt_target xt_target #define ipt_table xt_table #define ipt_get_revision xt_get_revision /* Yes, Virginia, you have to zero the padding. */ struct ipt_ip { /* Source and destination IP addr */ struct in_addr src, dst; /* Mask for src and dest IP addr */ struct in_addr smsk, dmsk; char iniface[IFNAMSIZ], outiface[IFNAMSIZ]; unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ]; /* Protocol, 0 = ANY */ u_int16_t proto; /* Flags word */ u_int8_t flags; /* Inverse flags */ u_int8_t invflags; }; #define ipt_entry_match xt_entry_match #define ipt_entry_target xt_entry_target #define ipt_standard_target xt_standard_target #define ipt_counters xt_counters /* Values for "flag" field in struct ipt_ip (general ip structure). */ #define IPT_F_FRAG 0x01 /* Set if rule is a fragment rule */ #define IPT_F_GOTO 0x02 /* Set if jump is a goto */ #define IPT_F_MASK 0x03 /* All possible flag bits mask. */ /* Values for "inv" field in struct ipt_ip. */ #define IPT_INV_VIA_IN 0x01 /* Invert the sense of IN IFACE. */ #define IPT_INV_VIA_OUT 0x02 /* Invert the sense of OUT IFACE */ #define IPT_INV_TOS 0x04 /* Invert the sense of TOS. */ #define IPT_INV_SRCIP 0x08 /* Invert the sense of SRC IP. */ #define IPT_INV_DSTIP 0x10 /* Invert the sense of DST OP. */ #define IPT_INV_FRAG 0x20 /* Invert the sense of FRAG. */ #define IPT_INV_PROTO XT_INV_PROTO #define IPT_INV_MASK 0x7F /* All possible flag bits mask. */ /* This structure defines each of the firewall rules. Consists of 3 parts which are 1) general IP header stuff 2) match specific stuff 3) the target to perform if the rule matches */ struct ipt_entry { struct ipt_ip ip; /* Mark with fields that we care about. */ unsigned int nfcache; /* Size of ipt_entry + matches */ u_int16_t target_offset; /* Size of ipt_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. * * ATTENTION: check linux/in.h before adding new number here. */ #define IPT_BASE_CTL 64 #define IPT_SO_SET_REPLACE (IPT_BASE_CTL) #define IPT_SO_SET_ADD_COUNTERS (IPT_BASE_CTL + 1) #define IPT_SO_SET_MAX IPT_SO_SET_ADD_COUNTERS #define IPT_SO_GET_INFO (IPT_BASE_CTL) #define IPT_SO_GET_ENTRIES (IPT_BASE_CTL + 1) #define IPT_SO_GET_REVISION_MATCH (IPT_BASE_CTL + 2) #define IPT_SO_GET_REVISION_TARGET (IPT_BASE_CTL + 3) #define IPT_SO_GET_MAX IPT_SO_GET_REVISION_TARGET #define IPT_CONTINUE XT_CONTINUE #define IPT_RETURN XT_RETURN #include #define ipt_udp xt_udp #define ipt_tcp xt_tcp #define IPT_TCP_INV_SRCPT XT_TCP_INV_SRCPT #define IPT_TCP_INV_DSTPT XT_TCP_INV_DSTPT #define IPT_TCP_INV_FLAGS XT_TCP_INV_FLAGS #define IPT_TCP_INV_OPTION XT_TCP_INV_OPTION #define IPT_TCP_INV_MASK XT_TCP_INV_MASK #define IPT_UDP_INV_SRCPT XT_UDP_INV_SRCPT #define IPT_UDP_INV_DSTPT XT_UDP_INV_DSTPT #define IPT_UDP_INV_MASK XT_UDP_INV_MASK /* ICMP matching stuff */ struct ipt_icmp { u_int8_t type; /* type to match */ u_int8_t code[2]; /* range of code */ u_int8_t invflags; /* Inverse flags */ }; /* Values for "inv" field for struct ipt_icmp. */ #define IPT_ICMP_INV 0x01 /* Invert the sense of type/code test */ /* The argument to IPT_SO_GET_INFO */ struct ipt_getinfo { /* Which table: caller fills this in. */ char name[IPT_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_INET_NUMHOOKS]; /* Underflow points. */ unsigned int underflow[NF_INET_NUMHOOKS]; /* Number of entries */ unsigned int num_entries; /* Size of entries. */ unsigned int size; }; /* The argument to IPT_SO_SET_REPLACE. */ struct ipt_replace { /* Which table. */ char name[IPT_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_INET_NUMHOOKS]; /* Underflow points. */ unsigned int underflow[NF_INET_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 *counters; /* The entries (hang off end: not really an array). */ struct ipt_entry entries[0]; }; /* The argument to IPT_SO_ADD_COUNTERS. */ #define ipt_counters_info xt_counters_info /* The argument to IPT_SO_GET_ENTRIES. */ struct ipt_get_entries { /* Which table: user fills this in. */ char name[IPT_TABLE_MAXNAMELEN]; /* User fills this in: total entry size. */ unsigned int size; /* The entries. */ struct ipt_entry entrytable[0]; }; /* Standard return verdict, or do jump. */ #define IPT_STANDARD_TARGET XT_STANDARD_TARGET /* Error verdict. */ #define IPT_ERROR_TARGET XT_ERROR_TARGET /* Helper functions */ static __inline__ struct ipt_entry_target * ipt_get_target(struct ipt_entry *e) { return (void *)e + e->target_offset; } /* fn returns 0 to continue iteration */ #define IPT_MATCH_ITERATE(e, fn, args...) \ XT_MATCH_ITERATE(struct ipt_entry, e, fn, ## args) /* fn returns 0 to continue iteration */ #define IPT_ENTRY_ITERATE(entries, size, fn, args...) \ XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args) /* * Main firewall chains definitions and global var's definitions. */ #endif /* _IPTABLES_H */