/*      $OpenBSD: ber.h,v 1.5 2021/10/31 16:42:08 tb Exp $ */

/*
 * Copyright (c) 2007, 2012 Reyk Floeter <reyk@openbsd.org>
 * Copyright (c) 2006, 2007 Claudio Jeker <claudio@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _BER_H
#define _BER_H

struct ber_octetstring {
        size_t                   ostr_len;
        const void              *ostr_val;
};

struct ber_element {
        struct ber_element      *be_next;
        unsigned int             be_type;
        unsigned int             be_encoding;
        size_t                   be_len;
        off_t                    be_offs;
        int                      be_free;
        u_int8_t                 be_class;
        void                    (*be_cb)(void *, size_t);
        void                    *be_cbarg;
        union {
                struct ber_element      *bv_sub;
                void                    *bv_val;
                long long                bv_numeric;
        } be_union;
#define be_sub          be_union.bv_sub
#define be_val          be_union.bv_val
#define be_numeric      be_union.bv_numeric
};

struct ber {
        off_t    br_offs;
        u_char  *br_wbuf;
        u_char  *br_wptr;
        u_char  *br_wend;
        u_char  *br_rbuf;
        u_char  *br_rptr;
        u_char  *br_rend;

        unsigned int    (*br_application)(struct ber_element *);
};

/* well-known ber_element types */
#define BER_TYPE_DEFAULT        ((unsigned int)-1)
#define BER_TYPE_EOC            0
#define BER_TYPE_BOOLEAN        1
#define BER_TYPE_INTEGER        2
#define BER_TYPE_BITSTRING      3
#define BER_TYPE_OCTETSTRING    4
#define BER_TYPE_NULL           5
#define BER_TYPE_OBJECT         6
#define BER_TYPE_ENUMERATED     10
#define BER_TYPE_SEQUENCE       16
#define BER_TYPE_SET            17

/* ber classes */
#define BER_CLASS_UNIVERSAL     0x0
#define BER_CLASS_UNIV          BER_CLASS_UNIVERSAL
#define BER_CLASS_APPLICATION   0x1
#define BER_CLASS_APP           BER_CLASS_APPLICATION
#define BER_CLASS_CONTEXT       0x2
#define BER_CLASS_PRIVATE       0x3
#define BER_CLASS_MASK          0x3

/* common definitions */
#define BER_MIN_OID_LEN         2               /* X.690 section 8.19.5 */
#define BER_MAX_OID_LEN         128             /* RFC 2578 section 7.1.3 */
#define BER_MAX_SEQ_ELEMENTS    USHRT_MAX       /* 65535 */

struct ber_oid {
        u_int32_t       bo_id[BER_MAX_OID_LEN + 1];
        size_t          bo_n;
};

__BEGIN_DECLS
struct ber_element      *ober_get_element(unsigned int);
void                     ober_set_header(struct ber_element *, int,
                            unsigned int);
void                     ober_link_elements(struct ber_element *,
                            struct ber_element *);
struct ber_element      *ober_unlink_elements(struct ber_element *);
void                     ober_replace_elements(struct ber_element *,
                            struct ber_element *);
struct ber_element      *ober_add_sequence(struct ber_element *);
struct ber_element      *ober_add_set(struct ber_element *);
struct ber_element      *ober_add_integer(struct ber_element *, long long);
int                      ober_get_integer(struct ber_element *, long long *);
struct ber_element      *ober_add_enumerated(struct ber_element *, long long);
int                      ober_get_enumerated(struct ber_element *, long long *);
struct ber_element      *ober_add_boolean(struct ber_element *, int);
int                      ober_get_boolean(struct ber_element *, int *);
struct ber_element      *ober_add_string(struct ber_element *, const char *);
struct ber_element      *ober_add_nstring(struct ber_element *, const char *,
                            size_t);
struct ber_element      *ober_add_ostring(struct ber_element *,
                            struct ber_octetstring *);
int                      ober_get_string(struct ber_element *, char **);
int                      ober_get_nstring(struct ber_element *, void **,
                            size_t *);
int                      ober_get_ostring(struct ber_element *,
                            struct ber_octetstring *);
struct ber_element      *ober_add_bitstring(struct ber_element *, const void *,
                            size_t);
int                      ober_get_bitstring(struct ber_element *, void **,
                            size_t *);
struct ber_element      *ober_add_null(struct ber_element *);
int                      ober_get_null(struct ber_element *);
struct ber_element      *ober_add_eoc(struct ber_element *);
int                      ober_get_eoc(struct ber_element *);
struct ber_element      *ober_add_oid(struct ber_element *, struct ber_oid *);
struct ber_element      *ober_add_noid(struct ber_element *, struct ber_oid *, int);
struct ber_element      *ober_add_oidstring(struct ber_element *, const char *);
int                      ober_get_oid(struct ber_element *, struct ber_oid *);
size_t                   ober_oid2ber(struct ber_oid *, u_int8_t *, size_t);
int                      ober_string2oid(const char *, struct ber_oid *);
struct ber_element      *ober_printf_elements(struct ber_element *, char *, ...);
int                      ober_scanf_elements(struct ber_element *, char *, ...);
ssize_t                  ober_get_writebuf(struct ber *, void **);
ssize_t                  ober_write_elements(struct ber *, struct ber_element *);
void                     ober_set_readbuf(struct ber *, void *, size_t);
struct ber_element      *ober_read_elements(struct ber *, struct ber_element *);
off_t                    ober_getpos(struct ber_element *);
struct ber_element      *ober_dup(struct ber_element *);
void                     ober_free_element(struct ber_element *);
void                     ober_free_elements(struct ber_element *);
size_t                   ober_calc_len(struct ber_element *);
void                     ober_set_application(struct ber *,
                            unsigned int (*)(struct ber_element *));
void                     ober_set_writecallback(struct ber_element *,
                            void (*)(void *, size_t), void *);
void                     ober_free(struct ber *);
int                      ober_oid_cmp(struct ber_oid *, struct ber_oid *);

__END_DECLS

#endif /* _BER_H */