/*
 * ASN.1 DER parsing
 * Copyright (c) 2006, Jouni Malinen <j@w1.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include <stdio.h>
#include <string.h>
#include <stdint.h>

#ifndef ASN1_H
#define ASN1_H

#define ASN1_TAG_EOC		0x00 /* not used with DER */
#define ASN1_TAG_BOOLEAN	0x01
#define ASN1_TAG_INTEGER	0x02
#define ASN1_TAG_BITSTRING	0x03
#define ASN1_TAG_OCTETSTRING	0x04
#define ASN1_TAG_NULL		0x05
#define ASN1_TAG_OID		0x06
#define ASN1_TAG_OBJECT_DESCRIPTOR	0x07 /* not yet parsed */
#define ASN1_TAG_EXTERNAL	0x08 /* not yet parsed */
#define ASN1_TAG_REAL		0x09 /* not yet parsed */
#define ASN1_TAG_ENUMERATED	0x0A /* not yet parsed */
#define ASN1_TAG_UTF8STRING	0x0C /* not yet parsed */
#define ANS1_TAG_RELATIVE_OID	0x0D
#define ASN1_TAG_SEQUENCE	0x10 /* shall be constructed */
#define ASN1_TAG_SET		0x11
#define ASN1_TAG_NUMERICSTRING	0x12 /* not yet parsed */
#define ASN1_TAG_PRINTABLESTRING	0x13
#define ASN1_TAG_TG1STRING	0x14 /* not yet parsed */
#define ASN1_TAG_VIDEOTEXSTRING	0x15 /* not yet parsed */
#define ASN1_TAG_IA5STRING	0x16
#define ASN1_TAG_UTCTIME	0x17
#define ASN1_TAG_GENERALIZEDTIME	0x18 /* not yet parsed */
#define ASN1_TAG_GRAPHICSTRING	0x19 /* not yet parsed */
#define ASN1_TAG_VISIBLESTRING	0x1A
#define ASN1_TAG_GENERALSTRING	0x1B /* not yet parsed */
#define ASN1_TAG_UNIVERSALSTRING	0x1C /* not yet parsed */
#define ASN1_TAG_BMPSTRING	0x1D /* not yet parsed */

#define ASN1_CLASS_UNIVERSAL		0
#define ASN1_CLASS_APPLICATION		1
#define ASN1_CLASS_CONTEXT_SPECIFIC	2
#define ASN1_CLASS_PRIVATE		3


struct asn1_hdr {
    const uint8_t *payload;
    uint8_t identifier, class, constructed;
    unsigned int tag, length;
};

#define ASN1_MAX_OID_LEN 20
struct asn1_oid {
    unsigned long oid[ASN1_MAX_OID_LEN];
    size_t len;
};


int asn1_get_next(const uint8_t *buf, size_t len, struct asn1_hdr *hdr);
int asn1_parse_oid(const uint8_t *buf, size_t len, struct asn1_oid *oid);
int asn1_get_oid(const uint8_t *buf, size_t len, struct asn1_oid *oid,
                 const uint8_t **next);
void asn1_oid_to_str(struct asn1_oid *oid, char *buf, size_t len);
unsigned long asn1_bit_string_to_long(const uint8_t *buf, size_t len);

#endif /* ASN1_H */
