/*-
 * Copyright (c) 2009-2014 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This material is based upon work partially supported by The
 * NetBSD Foundation under a contract with Mindaugas Rasiukevicius.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Public NPF interfaces.
 */

#ifndef _NPF_NET_H_
#define _NPF_NET_H_

#include <sys/param.h>
#include <sys/types.h>

#define	NPF_VERSION		22

#if defined(_NPF_STANDALONE)
#include "npf_stand.h"
#else
#include <sys/ioctl.h>
#include <netinet/in_systm.h>
#include <netinet/in.h>
#endif

struct npf;
typedef struct npf npf_t;

/*
 * Storage of address (both for IPv4 and IPv6) and netmask.
 */
typedef union {
	uint8_t			word8[16];
	uint16_t		word16[8];
	uint32_t		word32[4];
} npf_addr_t;

typedef uint8_t			npf_netmask_t;

#define	NPF_MAX_NETMASK		(128)
#define	NPF_NO_NETMASK		((npf_netmask_t)~0)

/* BPF coprocessor. */
#if defined(NPF_BPFCOP)
#define	NPF_COP_L3		0
#define	NPF_COP_TABLE		1

#define	BPF_MW_IPVER		0
#define	BPF_MW_L4OFF		1
#define	BPF_MW_L4PROTO		2
#endif
/* The number of words used. */
#define	NPF_BPF_NWORDS		3

/*
 * In-kernel declarations and definitions.
 */

#if defined(_KERNEL) || defined(_NPF_STANDALONE)

#define	NPF_DECISION_BLOCK	0
#define	NPF_DECISION_PASS	1

#define	NPF_EXT_MODULE(name, req)	\
    MODULE(MODULE_CLASS_MISC, name, (sizeof(req) - 1) ? ("npf," req) : "npf")

#include <net/if.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/icmp6.h>

/*
 * Network buffer interface.
 */

#define	NBUF_DATAREF_RESET	0x01

struct mbuf;
struct nbuf;
typedef struct nbuf nbuf_t;

void		nbuf_init(npf_t *, nbuf_t *, struct mbuf *, const ifnet_t *);
void		nbuf_reset(nbuf_t *);
struct mbuf *	nbuf_head_mbuf(nbuf_t *);

bool		nbuf_flag_p(const nbuf_t *, int);
void		nbuf_unset_flag(nbuf_t *, int);

void *		nbuf_dataptr(nbuf_t *);
size_t		nbuf_offset(const nbuf_t *);
void *		nbuf_advance(nbuf_t *, size_t, size_t);

void *		nbuf_ensure_contig(nbuf_t *, size_t);
void *		nbuf_ensure_writable(nbuf_t *, size_t);

bool		nbuf_cksum_barrier(nbuf_t *, int);
int		nbuf_add_tag(nbuf_t *, uint32_t);
int		nbuf_find_tag(nbuf_t *, uint32_t *);

/*
 * Packet information cache.
 */

#define	NPC_IP4		0x01	/* Indicates IPv4 header. */
#define	NPC_IP6		0x02	/* Indicates IPv6 header. */
#define	NPC_IPFRAG	0x04	/* IPv4/IPv6 fragment. */
#define	NPC_LAYER4	0x08	/* Layer 4 has been fetched. */

#define	NPC_TCP		0x10	/* TCP header. */
#define	NPC_UDP		0x20	/* UDP header. */
#define	NPC_ICMP	0x40	/* ICMP header. */
#define	NPC_ICMP_ID	0x80	/* ICMP with query ID. */

#define	NPC_ALG_EXEC	0x100	/* ALG execution. */

#define	NPC_FMTERR	0x200	/* Format error. */

#define	NPC_IP46	(NPC_IP4|NPC_IP6)

struct npf_connkey;

typedef struct {
	/* NPF context, information flags and the nbuf. */
	npf_t *			npc_ctx;
	uint32_t		npc_info;
	nbuf_t *		npc_nbuf;

	/*
	 * Pointers to the IP source and destination addresses,
	 * and the address length (4 for IPv4 or 16 for IPv6).
	 */
	npf_addr_t *		npc_ips[2];
	uint8_t			npc_alen;

	/* IP header length and L4 protocol. */
	uint32_t		npc_hlen;
	uint16_t		npc_proto;

	/* IPv4, IPv6. */
	union {
		struct ip *		v4;
		struct ip6_hdr *	v6;
	} npc_ip;

	/* TCP, UDP, ICMP or other protocols. */
	union {
		struct tcphdr *		tcp;
		struct udphdr *		udp;
		struct icmp *		icmp;
		struct icmp6_hdr *	icmp6;
		void *			hdr;
	} npc_l4;

	/*
	 * Override the connection key, if not NULL.  This affects the
	 * behaviour of npf_conn_lookup() and npf_conn_establish().
	 * Note: npc_ckey is of npf_connkey_t type.
	 */
	const void *		npc_ckey;
} npf_cache_t;

static inline bool
npf_iscached(const npf_cache_t *npc, const int inf)
{
	KASSERT(npc->npc_nbuf != NULL);
	return __predict_true((npc->npc_info & inf) != 0);
}

/*
 * Misc.
 */

bool		npf_autounload_p(void);

#endif	/* _KERNEL */

#define	NPF_SRC		0
#define	NPF_DST		1

/* Rule attributes. */
#define	NPF_RULE_PASS			0x00000001
#define	NPF_RULE_GROUP			0x00000002
#define	NPF_RULE_FINAL			0x00000004
#define	NPF_RULE_STATEFUL		0x00000008
#define	NPF_RULE_RETRST			0x00000010
#define	NPF_RULE_RETICMP		0x00000020
#define	NPF_RULE_DYNAMIC		0x00000040
#define	NPF_RULE_GSTATEFUL		0x00000080

#define	NPF_DYNAMIC_GROUP		(NPF_RULE_GROUP | NPF_RULE_DYNAMIC)

#define	NPF_RULE_IN			0x10000000
#define	NPF_RULE_OUT			0x20000000
#define	NPF_RULE_DIMASK			(NPF_RULE_IN | NPF_RULE_OUT)
#define	NPF_RULE_FORW			0x40000000

/* Private range of rule attributes (not public and should not be set). */
#define	NPF_RULE_PRIVMASK		0x0f000000

#define	NPF_RULE_MAXNAMELEN		64
#define	NPF_RULE_MAXKEYLEN		32

/* Priority values. */
#define	NPF_PRI_FIRST			(-2)
#define	NPF_PRI_LAST			(-1)

/* Types of code. */
#define	NPF_CODE_BPF			1

/* Address translation types and flags. */
#define	NPF_NATIN			1
#define	NPF_NATOUT			2

#define	NPF_NAT_PORTS			0x01
#define	NPF_NAT_PORTMAP			0x02
#define	NPF_NAT_STATIC			0x04

#define	NPF_NAT_PRIVMASK		0x0f000000

#define	NPF_ALGO_NONE			0
#define	NPF_ALGO_NETMAP			1
#define	NPF_ALGO_IPHASH			2
#define	NPF_ALGO_RR			3
#define	NPF_ALGO_NPT66			4

/* Table types. */
#define	NPF_TABLE_IPSET			1
#define	NPF_TABLE_LPM			2
#define	NPF_TABLE_CONST			3
#define	NPF_TABLE_IFADDR		4

#define	NPF_TABLE_MAXNAMELEN		32

/* Layers. */
#define	NPF_LAYER_2			2
#define	NPF_LAYER_3			3

/*
 * Flags passed via nbuf tags.
 */
#define	NPF_NTAG_PASS			0x0001

/*
 * Rule commands (non-ioctl).
 */

#define	NPF_CMD_RULE_ADD		1
#define	NPF_CMD_RULE_INSERT		2
#define	NPF_CMD_RULE_REMOVE		3
#define	NPF_CMD_RULE_REMKEY		4
#define	NPF_CMD_RULE_LIST		5
#define	NPF_CMD_RULE_FLUSH		6

/*
 * NPF ioctl(2): table commands and structures.
 */

#define	NPF_CMD_TABLE_LOOKUP		1
#define	NPF_CMD_TABLE_ADD		2
#define	NPF_CMD_TABLE_REMOVE		3
#define	NPF_CMD_TABLE_LIST		4
#define	NPF_CMD_TABLE_FLUSH		5

typedef struct npf_ioctl_ent {
	int			alen;
	npf_addr_t		addr;
	npf_netmask_t		mask;
} npf_ioctl_ent_t;

typedef struct npf_ioctl_buf {
	void *			buf;
	size_t			len;
} npf_ioctl_buf_t;

typedef struct npf_ioctl_table {
	int			nct_cmd;
	const char *		nct_name;
	union {
		npf_ioctl_ent_t	ent;
		npf_ioctl_buf_t	buf;
	} nct_data;
} npf_ioctl_table_t;

/*
 * IOCTL operations.
 */

#define	IOC_NPF_VERSION		_IOR('N', 100, int)
#define	IOC_NPF_SWITCH		_IOW('N', 101, int)
#define	IOC_NPF_LOAD		_IOWR('N', 102, nvlist_ref_t)
#define	IOC_NPF_TABLE		_IOW('N', 103, struct npf_ioctl_table)
#define	IOC_NPF_STATS		_IOW('N', 104, void *)
#define	IOC_NPF_SAVE		_IOR('N', 105, nvlist_ref_t)
#define	IOC_NPF_RULE		_IOWR('N', 107, nvlist_ref_t)
#define	IOC_NPF_CONN_LOOKUP	_IOWR('N', 108, nvlist_ref_t)
#define	IOC_NPF_TABLE_REPLACE	_IOWR('N', 109, nvlist_ref_t)

/*
 * NPF error report.
 */

typedef struct {
	int64_t		id;
	char *		error_msg;
	char *		source_file;
	unsigned	source_line;
} npf_error_t;

/*
 * Statistics counters.
 */

typedef enum {
	/* Packets passed. */
	NPF_STAT_PASS_DEFAULT,
	NPF_STAT_PASS_RULESET,
	NPF_STAT_PASS_CONN,
	/* Packets blocked. */
	NPF_STAT_BLOCK_DEFAULT,
	NPF_STAT_BLOCK_RULESET,
	/* Connection and NAT entries. */
	NPF_STAT_CONN_CREATE,
	NPF_STAT_CONN_DESTROY,
	NPF_STAT_NAT_CREATE,
	NPF_STAT_NAT_DESTROY,
	/* Invalid state cases. */
	NPF_STAT_INVALID_STATE,
	NPF_STAT_INVALID_STATE_TCP1,
	NPF_STAT_INVALID_STATE_TCP2,
	NPF_STAT_INVALID_STATE_TCP3,
	/* Raced packets. */
	NPF_STAT_RACE_CONN,
	NPF_STAT_RACE_NAT,
	/* Fragments. */
	NPF_STAT_FRAGMENTS,
	NPF_STAT_REASSEMBLY,
	NPF_STAT_REASSFAIL,
	/* Other errors. */
	NPF_STAT_ERROR,
	/* nbuf non-contiguous cases. */
	NPF_STAT_NBUF_NONCONTIG,
	NPF_STAT_NBUF_CONTIG_FAIL,
	/* Count (last). */
	NPF_STATS_COUNT
} npf_stats_t;

#define	NPF_STATS_SIZE		(sizeof(uint64_t) * NPF_STATS_COUNT)

#endif	/* _NPF_NET_H_ */