text: /*
   * lib/krb5/krb/ser_cksum.c
   *
   * Copyright 1995 by the Massachusetts Institute of Technology.
   * All Rights Reserved.
   *
   * Export of this software from the United States of America may
   *   require a specific license from the United States Government.
   *   It is the responsibility of any person or organization contemplating
   *   export to obtain such a license before exporting.
   *
   * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
   * distribute this software and its documentation for any purpose and
   * without fee is hereby granted, provided that the above copyright
   * notice appear in all copies and that both that copyright notice and
   * this permission notice appear in supporting documentation, and that
   * the name of M.I.T. not be used in advertising or publicity pertaining
   * to distribution of the software without specific, written prior
   * permission.  Furthermore if you modify this software you must label
   * your software as modified software and not distribute it in such a
   * fashion that it might be confused with the original M.I.T. software.
   * M.I.T. makes no representations about the suitability of
   * this software for any purpose.  It is provided "as is" without express
   * or implied warranty.
   *
   */
  
  /*
   * ser_cksum.c - Serialize a krb5_checksum structure.
   */
  #include "k5-int.h"
  #include "int-proto.h"
  
  /*
   * Routines to deal with externalizing the krb5_checksum:
   *	krb5_checksum_esize();
   *	krb5_checksum_externalize();
   *	krb5_checksum_internalize();
   */
  static krb5_error_code krb5_checksum_esize
  	(krb5_context, krb5_pointer, size_t *);
  static krb5_error_code krb5_checksum_externalize
  	(krb5_context, krb5_pointer, krb5_octet **, size_t *);
  static krb5_error_code krb5_checksum_internalize
  	(krb5_context,krb5_pointer *, krb5_octet **, size_t *);
  
  /* Local data */
  static const krb5_ser_entry krb5_checksum_ser_entry = {
      KV5M_CHECKSUM,			/* Type			*/
      krb5_checksum_esize,		/* Sizer routine	*/
      krb5_checksum_externalize,		/* Externalize routine	*/
      krb5_checksum_internalize		/* Internalize routine	*/
  };
  
  /*
   * krb5_checksum_esize()	- Determine the size required to externalize
   *				  the krb5_checksum.
   */
  /*ARGSUSED*/
  static krb5_error_code
  krb5_checksum_esize(krb5_context kcontext, krb5_pointer arg, size_t *sizep)
  {
      krb5_error_code	kret;
      krb5_checksum	*checksum;
  
      /*
       * krb5_checksum requires:
       *	krb5_int32		for KV5M_CHECKSUM
       *	krb5_int32		for checksum_type
       *	krb5_int32		for length
       *	krb5_int32		for KV5M_CHECKSUM
       *	checksum->length	for contents
       */
      kret = EINVAL;
      /* Solaris Kerberos */
      checksum = (krb5_checksum *) arg;
      if (checksum) {
  	*sizep += (sizeof(krb5_int32) +
  		   sizeof(krb5_int32) +
  		   sizeof(krb5_int32) +
  		   sizeof(krb5_int32) +
  		   (size_t) checksum->length);
  	kret = 0;
      }
      return(kret);
  }
  
  /*
   * krb5_checksum_externalize()	- Externalize the krb5_checksum.
   */
  static krb5_error_code
  krb5_checksum_externalize(krb5_context kcontext, krb5_pointer arg, krb5_octet **buffer, size_t *lenremain)
  {
      krb5_error_code	kret;
      krb5_checksum	*checksum;
      size_t		required;
      krb5_octet		*bp;
      size_t		remain;
  
      required = 0;
      bp = *buffer;
      remain = *lenremain;
      kret = EINVAL;
      /* Solaris Kerberos */
      checksum = (krb5_checksum *) arg;
      if (checksum) {
  	kret = ENOMEM;
  	if (!krb5_checksum_esize(kcontext, arg, &required) &&
  	    (required <= remain)) {
  	    /* Our identifier */
  	    (void) krb5_ser_pack_int32(KV5M_CHECKSUM, &bp, &remain);
  		
  	    /* Our checksum_type */
  	    (void) krb5_ser_pack_int32((krb5_int32) checksum->checksum_type,
  				       &bp, &remain);
  
  	    /* Our length */
  	    (void) krb5_ser_pack_int32((krb5_int32) checksum->length,
  				       &bp, &remain);
  
  	    /* Our contents */
  	    (void) krb5_ser_pack_bytes(checksum->contents,
  				       (size_t) checksum->length,
  				       &bp, &remain);
  
  	    /* Finally, our trailer */
  	    (void) krb5_ser_pack_int32(KV5M_CHECKSUM, &bp, &remain);
  
  	    kret = 0;
  	    *buffer = bp;
  	    *lenremain = remain;
  	}
      }
      return(kret);
  }
  
  /*
   * krb5_checksum_internalize()	- Internalize the krb5_checksum.
   */
  /*ARGSUSED*/
  static krb5_error_code
  krb5_checksum_internalize(krb5_context kcontext, krb5_pointer *argp, krb5_octet **buffer, size_t *lenremain)
  {
      krb5_error_code	kret;
      krb5_checksum	*checksum;
      krb5_int32		ibuf;
      krb5_octet		*bp;
      size_t		remain;
  
      bp = *buffer;
      remain = *lenremain;
      kret = EINVAL;
      /* Read our magic number */
      if (krb5_ser_unpack_int32(&ibuf, &bp, &remain))
  	ibuf = 0;
      if (ibuf == KV5M_CHECKSUM) {
  	kret = ENOMEM;
  
  	/* Get a checksum */
  	if ((remain >= (2*sizeof(krb5_int32))) &&
  	    (checksum = (krb5_checksum *) MALLOC(sizeof(krb5_checksum)))) {
  	    (void) memset(checksum, 0, sizeof(krb5_checksum));
  
  	    /* Get the checksum_type */
  	    (void) krb5_ser_unpack_int32(&ibuf, &bp, &remain);
  	    checksum->checksum_type = (krb5_cksumtype) ibuf;
  
  	    /* Get the length */
  	    (void) krb5_ser_unpack_int32(&ibuf, &bp, &remain);
  	    checksum->length = (int) ibuf;
  
  	    /* Get the string */
  	    /* Solaris Kerberos */
  	    if (ibuf) 
  		checksum->contents = (krb5_octet *)
  		 			 MALLOC((size_t) (ibuf));
  
  	    if (!ibuf ||
  		((checksum->contents) &&
  		 !(kret = krb5_ser_unpack_bytes(checksum->contents,
  						(size_t) ibuf,
  						&bp, &remain)))) {
  
  		/* Get the trailer */
  		kret = krb5_ser_unpack_int32(&ibuf, &bp, &remain);
  		if (!kret && (ibuf == KV5M_CHECKSUM)) {
  		    checksum->magic = KV5M_CHECKSUM;
  		    *buffer = bp;
  		    *lenremain = remain;
  		    *argp = (krb5_pointer) checksum;
  		}
  		else
  		    kret = EINVAL;
  	    }
  	    if (kret) {
  		if (checksum->contents)
  		    FREE(checksum->contents, checksum->length);
  		FREE(checksum, sizeof (krb5_checksum));
  	    }
  	}
      }
      return(kret);
  }
  
  /*
   * Register the checksum serializer.
   */
  krb5_error_code
  krb5_ser_checksum_init(krb5_context kcontext)
  {
      return(krb5_register_serializer(kcontext, &krb5_checksum_ser_entry));
  }
  