| /* |
| * 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 <linux/netfilter_ipv4.h> |
| |
| #define IPT_FUNCTION_MAXNAMELEN 30 |
| #define IPT_TABLE_MAXNAMELEN 32 |
| |
| /* 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; |
| }; |
| |
| struct ipt_entry_match |
| { |
| union { |
| struct { |
| u_int16_t match_size; |
| |
| /* Used by userspace */ |
| char name[IPT_FUNCTION_MAXNAMELEN-1]; |
| |
| u_int8_t revision; |
| } user; |
| struct { |
| u_int16_t match_size; |
| |
| /* Used inside the kernel */ |
| struct ipt_match *match; |
| } kernel; |
| |
| /* Total length */ |
| u_int16_t match_size; |
| } u; |
| |
| unsigned char data[0]; |
| }; |
| |
| struct ipt_entry_target |
| { |
| union { |
| struct { |
| u_int16_t target_size; |
| |
| /* Used by userspace */ |
| char name[IPT_FUNCTION_MAXNAMELEN-1]; |
| |
| u_int8_t revision; |
| } user; |
| struct { |
| u_int16_t target_size; |
| |
| /* Used inside the kernel */ |
| struct ipt_target *target; |
| } kernel; |
| |
| /* Total length */ |
| u_int16_t target_size; |
| } u; |
| |
| unsigned char data[0]; |
| }; |
| |
| struct ipt_standard_target |
| { |
| struct ipt_entry_target target; |
| int verdict; |
| }; |
| |
| struct ipt_counters |
| { |
| u_int64_t pcnt, bcnt; /* Packet and byte 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_MASK 0x01 /* 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 0x40 /* Invert the sense of 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 ipt_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 IPT_BASE_CTL 64 /* base for firewall socket options */ |
| |
| #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 |
| |
| /* CONTINUE verdict for targets */ |
| #define IPT_CONTINUE 0xFFFFFFFF |
| |
| /* For standard target */ |
| #define IPT_RETURN (-NF_MAX_VERDICT - 1) |
| |
| /* TCP matching stuff */ |
| struct ipt_tcp |
| { |
| u_int16_t spts[2]; /* Source port range. */ |
| u_int16_t dpts[2]; /* Destination port range. */ |
| u_int8_t option; /* TCP Option iff non-zero*/ |
| u_int8_t flg_mask; /* TCP flags mask byte */ |
| u_int8_t flg_cmp; /* TCP flags compare byte */ |
| u_int8_t invflags; /* Inverse flags */ |
| }; |
| |
| /* Values for "inv" field in struct ipt_tcp. */ |
| #define IPT_TCP_INV_SRCPT 0x01 /* Invert the sense of source ports. */ |
| #define IPT_TCP_INV_DSTPT 0x02 /* Invert the sense of dest ports. */ |
| #define IPT_TCP_INV_FLAGS 0x04 /* Invert the sense of TCP flags. */ |
| #define IPT_TCP_INV_OPTION 0x08 /* Invert the sense of option test. */ |
| #define IPT_TCP_INV_MASK 0x0F /* All possible flags. */ |
| |
| /* UDP matching stuff */ |
| struct ipt_udp |
| { |
| u_int16_t spts[2]; /* Source port range. */ |
| u_int16_t dpts[2]; /* Destination port range. */ |
| u_int8_t invflags; /* Inverse flags */ |
| }; |
| |
| /* Values for "invflags" field in struct ipt_udp. */ |
| #define IPT_UDP_INV_SRCPT 0x01 /* Invert the sense of source ports. */ |
| #define IPT_UDP_INV_DSTPT 0x02 /* Invert the sense of dest ports. */ |
| #define IPT_UDP_INV_MASK 0x03 /* All possible flags. */ |
| |
| /* 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_IP_NUMHOOKS]; |
| |
| /* Underflow points. */ |
| unsigned int underflow[NF_IP_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_IP_NUMHOOKS]; |
| |
| /* Underflow points. */ |
| unsigned int underflow[NF_IP_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 ipt_counters *counters; |
| |
| /* The entries (hang off end: not really an array). */ |
| struct ipt_entry entries[0]; |
| }; |
| |
| /* The argument to IPT_SO_ADD_COUNTERS. */ |
| struct ipt_counters_info |
| { |
| /* Which table. */ |
| char name[IPT_TABLE_MAXNAMELEN]; |
| |
| unsigned int num_counters; |
| |
| /* The counters (actually `number' of these). */ |
| struct ipt_counters counters[0]; |
| }; |
| |
| /* 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]; |
| }; |
| |
| /* The argument to IPT_SO_GET_REVISION_*. Returns highest revision |
| * kernel supports, if >= revision. */ |
| struct ipt_get_revision |
| { |
| char name[IPT_FUNCTION_MAXNAMELEN-1]; |
| |
| u_int8_t revision; |
| }; |
| |
| /* Standard return verdict, or do jump. */ |
| #define IPT_STANDARD_TARGET "" |
| /* Error verdict. */ |
| #define IPT_ERROR_TARGET "ERROR" |
| |
| /* 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...) \ |
| ({ \ |
| unsigned int __i; \ |
| int __ret = 0; \ |
| struct ipt_entry_match *__match; \ |
| \ |
| for (__i = sizeof(struct ipt_entry); \ |
| __i < (e)->target_offset; \ |
| __i += __match->u.match_size) { \ |
| __match = (void *)(e) + __i; \ |
| \ |
| __ret = fn(__match , ## args); \ |
| if (__ret != 0) \ |
| break; \ |
| } \ |
| __ret; \ |
| }) |
| |
| /* fn returns 0 to continue iteration */ |
| #define IPT_ENTRY_ITERATE(entries, size, fn, args...) \ |
| ({ \ |
| unsigned int __i; \ |
| int __ret = 0; \ |
| struct ipt_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. |
| */ |
| #endif /* _IPTABLES_H */ |