/* * WARNING: Do *NOT* ever include this file, only for internal use! * Use the set/get API in order to set/get the conntrack attributes */ #ifndef _NFCT_OBJECT_H_ #define _NFCT_OBJECT_H_ /* * nfct callback handler object */ struct nfct_handle { struct nfnl_handle *nfnlh; struct nfnl_subsys_handle *nfnlssh_ct; struct nfnl_subsys_handle *nfnlssh_exp; /* callback handler for the new API */ struct nfnl_callback nfnl_cb; int (*cb)(enum nf_conntrack_msg_type type, struct nf_conntrack *ct, void *data); /* This is the second version of the callback that includes * the Netlink header. This is the result of an early design * error, hiding Netlink details is evil. You end needing some * internal information at some point like the Netlink PortID. */ int (*cb2)(const struct nlmsghdr *nlh, enum nf_conntrack_msg_type type, struct nf_conntrack *ct, void *data); int (*expect_cb)(enum nf_conntrack_msg_type type, struct nf_expect *exp, void *data); }; /* container used to pass data to nfnl callbacks */ struct __data_container { struct nfct_handle *h; enum nf_conntrack_msg_type type; void *data; }; /* * conntrack object */ union __nfct_l4_src { /* Add other protocols here. */ u_int16_t all; struct { u_int16_t port; } tcp; struct { u_int16_t port; } udp; struct { u_int16_t id; } icmp; struct { u_int16_t port; } sctp; struct { u_int16_t port; } dccp; }; union __nfct_l4_dst { /* Add other protocols here. */ u_int16_t all; struct { u_int16_t port; } tcp; struct { u_int16_t port; } udp; struct { u_int8_t type, code; } icmp; struct { u_int16_t port; } sctp; struct { u_int16_t port; } dccp; }; union __nfct_address { u_int32_t v4; struct in6_addr v6; }; struct __nfct_tuple { union __nfct_address src; union __nfct_address dst; u_int8_t l3protonum; u_int8_t protonum; union __nfct_l4_src l4src; union __nfct_l4_dst l4dst; struct { u_int32_t correction_pos; u_int32_t offset_before; u_int32_t offset_after; } natseq; }; #define __DIR_ORIG 0 #define __DIR_REPL 1 #define __DIR_MASTER 2 #define __DIR_MAX __DIR_MASTER+1 union __nfct_protoinfo { struct { u_int8_t state; struct { u_int8_t value; u_int8_t mask; } flags[__DIR_MAX]; } tcp; struct { u_int8_t state; u_int32_t vtag[__DIR_MAX]; } sctp; struct { u_int8_t state; u_int8_t role; u_int64_t handshake_seq; } dccp; }; struct __nfct_counters { u_int64_t packets; u_int64_t bytes; }; struct __nfct_nat { u_int32_t min_ip, max_ip; union __nfct_l4_src l4min, l4max; }; struct nf_conntrack { struct __nfct_tuple tuple[__DIR_MAX]; u_int32_t timeout; u_int32_t mark; u_int32_t secmark; u_int32_t status; u_int32_t use; u_int32_t id; /* xt_helper uses a length size of 30 bytes, however, no helper name in * the tree has exceeded 16 bytes length. Since 2.6.29, the maximum * length accepted is 16 bytes, this limit is enforced during module load. */ #define __NFCT_HELPER_NAMELEN 16 char helper_name[__NFCT_HELPER_NAMELEN]; union __nfct_protoinfo protoinfo; struct __nfct_counters counters[__DIR_MAX]; struct __nfct_nat snat; struct __nfct_nat dnat; #define __NFCT_BITSET 2 u_int32_t set[__NFCT_BITSET]; }; /* * conntrack filter object */ struct nfct_filter { /* * As many other objects in this library, the attributes are * private. This gives us the chance to modify the layout and * object size. * * Another observation, although this object might seem too * memory consuming, it is only needed to build the filter. Thus, * once it is attached, you can release this object. */ /* * filter logic: use positive or negative logic */ enum nfct_filter_logic logic[NFCT_FILTER_MAX]; /* * This the layer 4 protocol map for filtering. Not more than * 255 protocols (maximum is IPPROTO_MAX which is 256). Actually, * I doubt that anyone can reach such a limit. */ #define __FILTER_L4PROTO_MAX 255 u_int32_t l4proto_map[IPPROTO_MAX/32]; u_int32_t l4proto_len; struct { /* * No limitations in the protocol filtering. We use a map of * 16 bits per protocol. As for now, DCCP has 10 states, TCP has * 10 states, SCTP has 8 state. Therefore, 16 bits is enough. */ #define __FILTER_PROTO_MAX 16 u_int16_t map; u_int16_t len; } l4proto_state[IPPROTO_MAX]; #define __FILTER_ADDR_SRC 0 #define __FILTER_ADDR_DST 1 /* * FIXME: For IPv4 filtering, up to 127 IPs by now. * This limitation is related to the existing autogenerated BSF code * (two BSF lines per comparison) and the fact that the maximum * jump offset is 0xff which is 255. */ u_int32_t l3proto_elems[2]; struct { #define __FILTER_ADDR_MAX 127 u_int32_t addr; u_int32_t mask; } l3proto[2][__FILTER_ADDR_MAX]; /* * FIXME: For IPv6 filtering, up to 20 IPs/masks (12 BSF lines * per comparison). I think that it is not worthy to try to support * more than that for performance reasons. It seems that oprofile * shows bad numbers for very large BSF code. */ u_int32_t l3proto_elems_ipv6[2]; struct { #define __FILTER_IPV6_MAX 20 u_int32_t addr[4]; u_int32_t mask[4]; } l3proto_ipv6[2][__FILTER_IPV6_MAX]; u_int32_t set[1]; }; /* * expectation object */ struct nf_expect { struct nf_conntrack master; struct nf_conntrack expected; struct nf_conntrack mask; u_int32_t timeout; u_int32_t id; u_int16_t expectfn_queue_id; u_int32_t set[1]; }; #endif