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.\" $Id$
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.Dd March 20, 2004
.Dt KRB5_ENCRYPT 3
.Os HEIMDAL
.Sh NAME
.Nm krb5_crypto_getblocksize ,
.Nm krb5_crypto_getconfoundersize
.Nm krb5_crypto_getenctype ,
.Nm krb5_crypto_getpadsize ,
.Nm krb5_crypto_overhead ,
.Nm krb5_decrypt ,
.Nm krb5_decrypt_EncryptedData ,
.Nm krb5_decrypt_ivec ,
.Nm krb5_decrypt_ticket ,
.Nm krb5_encrypt ,
.Nm krb5_encrypt_EncryptedData ,
.Nm krb5_encrypt_ivec ,
.Nm krb5_enctype_disable ,
.Nm krb5_enctype_keysize ,
.Nm krb5_enctype_to_string ,
.Nm krb5_enctype_valid ,
.Nm krb5_get_wrapped_length ,
.Nm krb5_string_to_enctype
.Nd "encrypt and decrypt data, set and get encryption type parameters"
.Sh LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)
.Sh SYNOPSIS
.In krb5.h
.Ft krb5_error_code
.Fo krb5_encrypt
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "unsigned usage"
.Fa "void *data"
.Fa "size_t len"
.Fa "krb5_data *result"
.Fc
.Ft krb5_error_code
.Fo krb5_encrypt_EncryptedData
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "unsigned usage"
.Fa "void *data"
.Fa "size_t len"
.Fa "int kvno"
.Fa "EncryptedData *result"
.Fc
.Ft krb5_error_code
.Fo krb5_encrypt_ivec
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "unsigned usage"
.Fa "void *data"
.Fa "size_t len"
.Fa "krb5_data *result"
.Fa "void *ivec"
.Fc
.Ft krb5_error_code
.Fo krb5_decrypt
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "unsigned usage"
.Fa "void *data"
.Fa "size_t len"
.Fa "krb5_data *result"
.Fc
.Ft krb5_error_code
.Fo krb5_decrypt_EncryptedData
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "unsigned usage"
.Fa "EncryptedData *e"
.Fa "krb5_data *result"
.Fc
.Ft krb5_error_code
.Fo krb5_decrypt_ivec
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "unsigned usage"
.Fa "void *data"
.Fa "size_t len"
.Fa "krb5_data *result"
.Fa "void *ivec"
.Fc
.Ft krb5_error_code
.Fo krb5_decrypt_ticket
.Fa "krb5_context context"
.Fa "Ticket *ticket"
.Fa "krb5_keyblock *key"
.Fa "EncTicketPart *out"
.Fa "krb5_flags flags"
.Fc
.Ft krb5_error_code
.Fo krb5_crypto_getblocksize
.Fa "krb5_context context"
.Fa "size_t *blocksize"
.Fc
.Ft krb5_error_code
.Fo krb5_crypto_getenctype
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "krb5_enctype *enctype"
.Fc
.Ft krb5_error_code
.Fo krb5_crypto_getpadsize
.Fa "krb5_context context"
.Fa size_t *padsize"
.Fc
.Ft krb5_error_code
.Fo krb5_crypto_getconfoundersize
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa size_t *confoundersize"
.Fc
.Ft krb5_error_code
.Fo krb5_enctype_keysize
.Fa "krb5_context context"
.Fa "krb5_enctype type"
.Fa "size_t *keysize"
.Fc
.Ft krb5_error_code
.Fo krb5_crypto_overhead
.Fa "krb5_context context"
.Fa size_t *padsize"
.Fc
.Ft krb5_error_code
.Fo krb5_string_to_enctype
.Fa "krb5_context context"
.Fa "const char *string"
.Fa "krb5_enctype *etype"
.Fc
.Ft krb5_error_code
.Fo krb5_enctype_to_string
.Fa "krb5_context context"
.Fa "krb5_enctype etype"
.Fa "char **string"
.Fc
.Ft krb5_error_code
.Fo krb5_enctype_valid
.Fa "krb5_context context"
.Fa "krb5_enctype etype"
.Fc
.Ft void
.Fo krb5_enctype_disable
.Fa "krb5_context context"
.Fa "krb5_enctype etype"
.Fc
.Ft size_t
.Fo krb5_get_wrapped_length
.Fa "krb5_context context"
.Fa "krb5_crypto crypto"
.Fa "size_t data_len"
.Fc
.Sh DESCRIPTION
These functions are used to encrypt and decrypt data.
.Pp
.Fn krb5_encrypt_ivec
puts the encrypted version of
.Fa data
(of size
.Fa len )
in
.Fa result .
If the encryption type supports using derived keys,
.Fa usage
should be the appropriate key-usage.
.Fa ivec
is a pointer to a initial IV, it is modified to the end IV at the end of
the round.
Ivec should be the size of
If
.Dv NULL
is passed in, the default IV is used.
.Fn krb5_encrypt
does the same as
.Fn krb5_encrypt_ivec
but with
.Fa ivec
being
.Dv NULL .
.Fn krb5_encrypt_EncryptedData
does the same as
.Fn krb5_encrypt ,
but it puts the encrypted data in a
.Fa EncryptedData
structure instead. If
.Fa kvno
is not zero, it will be put in the (optional)
.Fa kvno
field in the
.Fa EncryptedData .
.Pp
.Fn krb5_decrypt_ivec ,
.Fn krb5_decrypt ,
and
.Fn krb5_decrypt_EncryptedData
works similarly.
.Pp
.Fn krb5_decrypt_ticket
decrypts the encrypted part of
.Fa ticket
with
.Fa key .
.Fn krb5_decrypt_ticket
also verifies the timestamp in the ticket, invalid flag and if the KDC
haven't verified the transited path, the transit path.
.Pp
.Fn krb5_enctype_keysize ,
.Fn krb5_crypto_getconfoundersize ,
.Fn krb5_crypto_getblocksize ,
.Fn krb5_crypto_getenctype ,
.Fn krb5_crypto_getpadsize ,
.Fn krb5_crypto_overhead
all returns various (sometimes) useful information from a crypto context.
.Fn krb5_crypto_overhead
is the combination of krb5_crypto_getconfoundersize,
krb5_crypto_getblocksize and krb5_crypto_getpadsize and return the
maximum overhead size.
.Pp
.Fn krb5_enctype_to_string
converts a encryption type number to a string that can be printable
and stored. The strings returned should be freed with
.Xr free 3 .
.Pp
.Fn krb5_string_to_enctype
converts a encryption type strings to a encryption type number that
can use used for other Kerberos crypto functions.
.Pp
.Fn krb5_enctype_valid
returns 0 if the encrypt is supported and not disabled, otherwise and
error code is returned.
.Pp
.Fn krb5_enctype_disable
(globally, for all contextes) disables the
.Fa enctype .
.Pp
.Fn krb5_get_wrapped_length
returns the size of an encrypted packet by
.Fa crypto
of length
.Fa data_len .
.\" .Sh EXAMPLE
.\" .Sh BUGS
.Sh SEE ALSO
.Xr krb5_create_checksum 3 ,
.Xr krb5_crypto_init 3