/*
 * Copyright (c) 2001-2003
 *	Fraunhofer Institute for Open Communication Systems (FhG Fokus).
 *	All rights reserved.
 *
 * Author: Harti Brandt <harti@freebsd.org>
 * 
 * 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 AUTHOR 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 AUTHOR 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.
 *
 * $Begemot: bsnmp/lib/snmpagent.h,v 1.13 2004/08/06 08:46:56 brandt Exp $
 *
 * Header file for SNMP functions. This requires snmp.h to be included.
 */
#ifndef snmp_agent_h_
#define snmp_agent_h_

struct snmp_dependency;

enum snmp_ret {
	/* OK, generate a response */
	SNMP_RET_OK	= 0,
	/* Error, ignore packet (no response) */
	SNMP_RET_IGN	= 1,
	/* Error, generate response from original packet */
	SNMP_RET_ERR	= 2
};

/* Semi-Opaque object for SET operations */
struct snmp_context {
	u_int	var_index;
	struct snmp_scratch *scratch;
	struct snmp_dependency *dep;
	void	*data;		/* user data */
	enum snmp_ret code;	/* return code */
};

struct snmp_scratch {
	void		*ptr1;
	void		*ptr2;
	uint32_t	int1;
	uint32_t	int2;
};

enum snmp_depop {
	SNMP_DEPOP_COMMIT,
	SNMP_DEPOP_ROLLBACK,
	SNMP_DEPOP_FINISH
};

typedef int (*snmp_depop_t)(struct snmp_context *, struct snmp_dependency *,
    enum snmp_depop);

struct snmp_dependency {
	struct asn_oid	obj;
	struct asn_oid	idx;
};

/*
 * The TREE
 */
enum snmp_node_type {
	SNMP_NODE_LEAF = 1,
	SNMP_NODE_COLUMN
};

enum snmp_op {
	SNMP_OP_GET 	= 1,
	SNMP_OP_GETNEXT,
	SNMP_OP_SET,
	SNMP_OP_COMMIT,
	SNMP_OP_ROLLBACK,
};

typedef int (*snmp_op_t)(struct snmp_context *, struct snmp_value *,
    u_int, u_int, enum snmp_op);

struct snmp_node {
	struct asn_oid oid;
	const char	*name;		/* name of the leaf */
	enum snmp_node_type type;	/* type of this node */
	enum snmp_syntax syntax;
	snmp_op_t	op;
	u_int		flags;
	uint32_t	index;		/* index data */
	void		*data;		/* application data */
	void		*tree_data;	/* application data */
};
extern struct snmp_node *tree;
extern u_int  tree_size;

#define SNMP_NODE_CANSET	0x0001	/* SET allowed */

#define SNMP_INDEXES_MAX	7
#define SNMP_INDEX_SHIFT	4
#define SNMP_INDEX_MASK	0xf
#define SNMP_INDEX_COUNT(V)	((V) & SNMP_INDEX_MASK)
#define SNMP_INDEX(V,I) \
	(((V) >> (((I) + 1) * SNMP_INDEX_SHIFT)) & SNMP_INDEX_MASK)

enum {
	SNMP_TRACE_GET		= 0x00000001,
	SNMP_TRACE_GETNEXT	= 0x00000002,
	SNMP_TRACE_SET		= 0x00000004,
	SNMP_TRACE_DEPEND	= 0x00000008,
	SNMP_TRACE_FIND		= 0x00000010,
};
/* trace flag for the following functions */
extern u_int snmp_trace;

/* called to write the trace */
extern void (*snmp_debug)(const char *fmt, ...);

enum snmp_ret snmp_get(struct snmp_pdu *pdu, struct asn_buf *resp_b,
    struct snmp_pdu *resp, void *);
enum snmp_ret snmp_getnext(struct snmp_pdu *pdu, struct asn_buf *resp_b,
    struct snmp_pdu *resp, void *);
enum snmp_ret snmp_getbulk(struct snmp_pdu *pdu, struct asn_buf *resp_b,
    struct snmp_pdu *resp, void *);
enum snmp_ret snmp_set(struct snmp_pdu *pdu, struct asn_buf *resp_b,
    struct snmp_pdu *resp, void *);

enum snmp_ret snmp_make_errresp(const struct snmp_pdu *, struct asn_buf *,
    struct asn_buf *);

struct snmp_dependency *snmp_dep_lookup(struct snmp_context *,
    const struct asn_oid *, const struct asn_oid *, size_t, snmp_depop_t);

struct snmp_context *snmp_init_context(void);
int snmp_dep_commit(struct snmp_context *);
int snmp_dep_rollback(struct snmp_context *);
void snmp_dep_finish(struct snmp_context *);

#endif