table of contents
NAME(3) | Library Functions Manual | NAME(3) |
NAME¶
krb5_checksum, krb5_checksum_disable, krb5_checksum_is_collision_proof, krb5_checksum_is_keyed, krb5_checksumsize, krb5_cksumtype_valid, krb5_copy_checksum, krb5_create_checksum, krb5_crypto_get_checksum_type krb5_free_checksum, krb5_free_checksum_contents, krb5_hmac, krb5_verify_checksum — creates, handles and verifies checksumsLIBRARY¶
Kerberos 5 Library (libkrb5, -lkrb5)SYNOPSIS¶
#include <krb5.h>typedef Checksum krb5_checksum;
void
krb5_checksum_disable(krb5_context context, krb5_cksumtype type); 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); krb5_error_code
krb5_cksumtype_valid(krb5_context context, krb5_cksumtype ctype); krb5_error_code
krb5_checksumsize(krb5_context context, krb5_cksumtype type, size_t *size); krb5_error_code
krb5_create_checksum(krb5_context context, krb5_crypto crypto, krb5_key_usage usage, int 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_error_code
krb5_crypto_get_checksum_type(krb5_context context, krb5_crypto crypto, krb5_cksumtype *type); void
krb5_free_checksum(krb5_context context, krb5_checksum *cksum); void
krb5_free_checksum_contents(krb5_context context, krb5_checksum *cksum); krb5_error_code
krb5_hmac(krb5_context context, krb5_cksumtype cktype, const void *data, size_t len, unsigned usage, krb5_keyblock *key, Checksum *result); krb5_error_code
krb5_copy_checksum(krb5_context context, const krb5_checksum *old, krb5_checksum **new);
DESCRIPTION¶
Thekrb5_checksum
structure holds a Kerberos checksum.
There is no component inside krb5_checksum
that is
directly referable.
The 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
RSA-MD5-DES. The “plain” hash functions MD5, and SHA1 are not
keyed.
krb5_crypto_get_checksum_type() returns the checksum type that
will be used when creating a checksum for the given
crypto context. This function is useful in combination
with krb5_checksumsize() when you want to know the size a
checksum will use when you create it.
krb5_cksumtype_valid() returns 0 or an error if the
checksumtype is implemented and not currently disabled in this kerberos
library.
krb5_checksumsize() returns the size of the outdata of
checksum function.
krb5_copy_checksum() returns a copy of the checksum
krb5_free_checksum() should use used to free the
new checksum.
krb5_free_checksum() free the checksum and the content of the
checksum.
krb5_free_checksum_contents() frees the content of checksum in
cksum.
krb5_hmac() calculates the HMAC over
data (with length len) using the
keyusage usage and keyblock key.
Note that keyusage is not always used in checksums.
krb5_checksum_disable globally disables the checksum type.
SEE ALSO¶
krb5_crypto_init(3), krb5_c_encrypt(3), krb5_encrypt(3)August 12, 2005 | HEIMDAL |