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/*
* 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_
#include <libnetfilter_conntrack/libnetfilter_conntrack.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_ct;
struct nfnl_callback nfnl_cb_exp;
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);
/* second version of the expect callback: it includes netlink header */
int (*expect_cb2)(const struct nlmsghdr *nlh,
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;
};
#define __DIR_ORIG 0
#define __DIR_REPL 1
#define __DIR_MAX __DIR_REPL+1
#define __DIR_MASTER 2
union __nfct_protoinfo {
struct {
u_int8_t state;
struct {
u_int8_t value;
u_int8_t mask;
} flags[__DIR_MAX];
u_int8_t wscale[__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 nfct_tuple_head {
struct __nfct_tuple orig;
#define __NFCT_BITSET 3
u_int32_t set[__NFCT_BITSET];
};
struct nf_conntrack {
struct nfct_tuple_head head;
struct __nfct_tuple repl;
struct __nfct_tuple master;
u_int32_t timeout;
u_int32_t mark;
u_int32_t secmark;
u_int32_t status;
u_int32_t use;
u_int32_t id;
u_int16_t zone;
char helper_name[NFCT_HELPER_NAME_MAX];
/* According to Eric Paris <eparis@redhat.com> this field can be up to 4096
* bytes long. For that reason, we allocate this dynamically. */
char *secctx;
union __nfct_protoinfo protoinfo;
struct __nfct_counters counters[__DIR_MAX];
struct __nfct_nat snat;
struct __nfct_nat dnat;
struct {
u_int32_t correction_pos;
u_int32_t offset_before;
u_int32_t offset_after;
} natseq[__DIR_MAX];
struct {
u_int64_t start;
u_int64_t stop;
} timestamp;
void *helper_info;
size_t helper_info_len;
};
/*
* 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];
};
/*
* conntrack filter dump object
*/
struct nfct_filter_dump {
struct nfct_filter_dump_mark mark;
u_int8_t l3num;
u_int32_t set;
};
/*
* expectation object
*/
#define __NFCT_EXPECTFN_MAX 24 /* maximum symbol length. */
struct nf_expect {
struct nfct_tuple_head master;
struct nfct_tuple_head expected;
struct nfct_tuple_head mask;
struct nfct_tuple_head nat;
u_int32_t timeout;
u_int32_t id;
u_int16_t zone;
u_int32_t flags;
u_int32_t class;
char helper_name[NFCT_HELPER_NAME_MAX];
u_int32_t nat_dir;
char expectfn[__NFCT_EXPECTFN_MAX];
u_int32_t set[1];
};
#endif
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