/*
 * Copyright 1994 by OpenVision Technologies, Inc.
 * 
 * Permission to use, copy, modify, distribute, and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appears in all copies and
 * that both that copyright notice and this permission notice appear in
 * supporting documentation, and that the name of OpenVision not be used
 * in advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission. OpenVision makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 * 
 * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, 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.
 */

#include <stdio.h>
#include "krb5.h"
#include <krb.h>
#include "krb524.h"

/*
 * I'm sure that this is reinventing the wheel, but I don't know where
 * the wheel is hidden.
 */

int  encode_v4tkt(KTEXT_ST *, char *, int *),
     encode_ktext(char **, int *, KTEXT_ST *),
     encode_bytes(char **, int *, char *, int),
     encode_int32(char **, int *, krb5_int32 *);

int  decode_v4tkt(KTEXT_ST *, char *, int *),
     decode_ktext(char **, int *, KTEXT_ST *),
     decode_bytes(char **, int *, char *, int),
     decode_int32(char **, int *, krb5_int32 *);

int encode_bytes(char **out, int *outlen, char *in, int len)
{
     if (len > *outlen)
	  return KRB524_ENCFULL;
     memcpy(*out, in, len);
     *out += len;
     *outlen -= len;
     return 0;
}

int encode_int32(char **out, int *outlen, krb5_int32 *v)
{
     int ret;
     int nv;

     nv = htonl(*v);
     return encode_bytes(out, outlen, (char *) &nv, sizeof(nv));
}

int encode_v4tkt(KTEXT_ST *v4tkt, char *buf, int *encoded_len)
{
     int buflen, ret;

     buflen = *encoded_len;

     if (ret = encode_int32(&buf, &buflen, &v4tkt->length))
	  return ret;
     if (ret = encode_bytes(&buf, &buflen, v4tkt->dat, MAX_KTXT_LEN))
	  return ret;
     if (ret = encode_int32(&buf, &buflen, &v4tkt->mbz))
	  return ret;

     *encoded_len -= buflen;
     return 0;
}

/* decode functions */

int decode_bytes(char **out, int *outlen, char *in, int len)
{
     if (len > *outlen)
	  return KRB524_DECEMPTY;
     memcpy(in, *out, len);
     *out += len;
     *outlen -= len;
     return 0;
}

int decode_int32(char **out, int *outlen, krb5_int32 *v)
{
     int ret;
     int nv;

     if (ret = decode_bytes(out, outlen, (char *) &nv, sizeof(nv)))
	  return ret;
     *v = ntohl(nv);
     return 0;
}

int decode_v4tkt(KTEXT_ST *v4tkt, char *buf, int *encoded_len)
{
     int buflen, ret;

     buflen = *encoded_len;
     if (ret = decode_int32(&buf, &buflen, &v4tkt->length))
	  return ret;
     if (ret = decode_bytes(&buf, &buflen, v4tkt->dat, MAX_KTXT_LEN))
	  return ret;
     if (ret = decode_int32(&buf, &buflen, &v4tkt->mbz))
	  return ret;
     *encoded_len -= buflen;
     return 0;
}