/*
 * $Source$
 * $Author$
 * $Id$
 *
 * Copyright 1989,1990 by the Massachusetts Institute of Technology.
 *
 * For copying and distribution information, please see the file
 * <krb5/mit-copyright.h>.
 *
 * Encryption interface-related declarations
 */

#include <krb5/copyright.h>

#ifndef __KRB5_ENCRYPTION__
#define __KRB5_ENCRYPTION__

typedef struct _krb5_keyblock {
    krb5_keytype keytype;
    int length;
    krb5_octet contents[1];		/* actually can be more, depending
					   on length */
} krb5_keyblock;

typedef struct _krb5_checksum {
    krb5_cksumtype checksum_type;	/* checksum type */
    int length;
    krb5_octet contents[1];		/* actually can be more, depending
					   on length */
} krb5_checksum;

typedef struct _krb5_encrypt_block {
    struct _krb5_cryptosystem_entry *crypto_entry;
    krb5_keyblock *key;
    krb5_pointer priv;			/* for private use, e.g. DES
					   key schedules */
} krb5_encrypt_block;

/* could be used in a table to find an etype and initialize a block */
typedef struct _krb5_cryptosystem_entry {
    int (*encrypt_func) PROTOTYPE((krb5_pointer in, krb5_pointer out,
				   size_t length,
				   krb5_encrypt_block *block));
    int (*decrypt_func) PROTOTYPE((krb5_pointer in, krb5_pointer out,
				   size_t length,
				   krb5_encrypt_block *block));
    int (*process_key) PROTOTYPE((krb5_encrypt_block *block,
				  krb5_keyblock *key));
    int (*finish_key) PROTOTYPE((krb5_encrypt_block *block));
    int (*string_to_key) PROTOTYPE((krb5_keytype keytype, krb5_keyblock *key,
				    char *string, krb5_principal *client));
    int (*random_key) PROTOTYPE((krb5_pointer sequence));
    krb5_pointer  (*init_random_key) PROTOTYPE((krb5_keyblock *key));
    int block_length;
    int pad_minimum;			/* needed for cksum size computation */
    int keysize;
    krb5_enctype proto_enctype;		/* encryption type,
					   (assigned protocol number) */
} krb5_cryptosystem_entry;

/* could be used in a table to find a sumtype */
typedef struct _krb5_checksum_entry {
    krb5_pointer  (*sum_func) PROTOTYPE ((krb5_pointer in, krb5_pointer out,
					  krb5_pointer seed,
					  size_t in_length,
					  size_t seed_length));
    int checksum_length;		/* length of stuff returned by
					   sum_func */
} krb5_checksum_entry;

/* per Kerberos v5 protocol spec */
#define	KEYTYPE_NULL		0x0000
#define KEYTYPE_DES		0x0001	/* Data Encryption Standard,
					   FIPS 46,81 */
#define KEYTYPE_LUCIFER		0x0002	/* Lucifer */

#define	ETYPE_NULL		0x0000
#define	ETYPE_DES_CBC_CRC	0x0001	/* DES cbc mode with CRC-32 */
#define	ETYPE_LUCIFER_CRC	0x0002

#define	CKSUMTYPE_CRC32		0x0001
#define	CKSUMTYPE_XXX		0x0002
#define	CKSUMTYPE_XEROX		0x0003
#define	CKSUMTYPE_DESCBC	0x0004

/* macros to determine if a type is a local type */
#define KEYTYPE_IS_LOCAL(keytype) (keytype & 0x8000)
#define ETYPE_IS_LOCAL(etype) (etype & 0x8000)
#define CKSUMTYPE_IS_LOCAL(cksumtype) (cksumtype & 0x8000)

#endif /* __KRB5_ENCRYPTION__ */