NAME    [Toc]    [Back]

     krb5_checksum_is_collision_proof, krb5_checksum_is_keyed,
     krb5_checksumsize,                     krb5_create_checksum,
krb5_verify_checksum - creates
     and verifies checksums

LIBRARY    [Toc]    [Back]

     Kerberos 5 Library (libkrb5, -lkrb5)

SYNOPSIS    [Toc]    [Back]

     #include <krb5.h>

     krb5_error_code
     krb5_create_checksum(krb5_context    context,    krb5_crypto
crypto,
             unsigned usage_or_type, void *data, size_t len,
             Checksum *result);

     krb5_error_code
     krb5_verify_checksum(krb5_context    context,    krb5_crypto
crypto,
             krb5_key_usage   usage,   void  *data,  size_t  len,
Checksum *cksum);

     krb5_boolean
     krb5_checksum_is_collision_proof(krb5_context context,
             krb5_cksumtype type);

     krb5_boolean
     krb5_checksum_is_keyed(krb5_context context,  krb5_cksumtype
type);

DESCRIPTION    [Toc]    [Back]

     These functions are used to create and verify checksums.
     krb5_create_checksum()  creates  a checksum of the specified
data, and puts
     it in result.  If crypto is  NULL,  usage_or_type  specifies
the checksum
     type  to  use;  it must not be keyed. Otherwise crypto is an
encryption context
 created by krb5_crypto_init(), and usage_or_type specifies a key-usage.


     krb5_verify_checksum()  verifies  the  checksum, against the
provided data.

     krb5_checksum_is_collision_proof() returns true is the specified checksum
     is collision proof (that it's very unlikely that two strings
has the same
     hash value, and that it's hard to find two strings that  has
the same
     hash).  Examples  of  collision proof checksums are MD5, and
SHA1, while
     CRC32 is not.

     krb5_checksum_is_keyed()  returns  true  if  the   specified
checksum type is
     keyed  (that  the hash value is a function of both the data,
and a separate
     key). Examples of keyed hash algorithms are  HMAC-SHA1-DES3,
and RSAMD5-DES.
  The ``plain'' hash functions MD5, and SHA1 are not
keyed.

SEE ALSO    [Toc]    [Back]

     krb5_crypto_init(3), krb5_encrypt(3)

 HEIMDAL                               April       7,        1999