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/*
* $Source$
* $Author$
*
* Copyright 1990 by the Massachusetts Institute of Technology.
*
* For copying and distribution information, please see the file
* <krb5/mit-copyright.h>.
*
* krb5_decode_kdc_rep() function.
*/
#if !defined(lint) && !defined(SABER)
static char rcsid_decode_kdc_c[] =
"$Id$";
#endif /* !lint & !SABER */
#include <krb5/copyright.h>
#include <krb5/krb5.h>
#include <krb5/krb5_err.h>
#include <krb5/isode_err.h>
#include <krb5/asn1.h>
#include <errno.h>
#include <krb5/ext-proto.h>
/* array of pointers into encryption systems */
extern krb5_cs_table_entry *csarray[];
extern int max_cryptosystem;
/*
Takes a KDC_REP message and decrypts encrypted part using etype and
*key, putting result in *rep.
dec_rep->client,ticket,session.last_req,server,caddrs
are all set to allocated storage which should be freed by the caller
when finished with the response.
If the response isn't a KDC_REP (tgs or as), it returns an error from
the decoding routines (usually ISODE_50_LOCAL_ERR_BADDECODE).
returns errors from encryption routines, system errors
*/
krb5_error_code
krb5_decode_kdc_rep(enc_rep, key, etype, dec_rep)
krb5_data *enc_rep;
krb5_keyblock *key;
krb5_enctype etype;
krb5_kdc_rep **dec_rep;
{
krb5_error_code retval;
krb5_kdc_rep *local_dec_rep;
krb5_encrypt_block eblock;
krb5_data scratch;
krb5_enc_kdc_rep_part *local_encpart;
/* XXX maybe caller should specify type expected? */
retval = decode_krb5_as_rep(enc_rep, &local_dec_rep);
switch (retval) {
case ISODE_50_LOCAL_ERR_BADMSGTYPE:
retval = decode_krb5_tgs_rep(enc_rep, &local_dec_rep);
switch (retval) {
case 0:
break;
default:
return(retval);
}
case 0:
break;
default:
return (retval);
}
scratch.length = local_dec_rep->enc_part.length;
if (!(scratch.data = malloc(local_dec_rep->enc_part.length))) {
krb5_free_kdc_rep(local_dec_rep);
return(ENOMEM);
}
if (!valid_etype(local_dec_rep->etype))
return KRB5KDC_ERR_ETYPE_NOSUPP;
/* put together an eblock for this encryption */
eblock.crypto_entry = csarray[local_dec_rep->etype]->system;
/* do any necessary key pre-processing */
if (retval = (*eblock.crypto_entry->process_key)(&eblock, key)) {
krb5_free_kdc_rep(local_dec_rep);
free(scratch.data);
return(retval);
}
/* call the encryption routine */
if (retval =
(*eblock.crypto_entry->decrypt_func)((krb5_pointer) local_dec_rep->enc_part.data,
(krb5_pointer) scratch.data,
scratch.length, &eblock)) {
(void) (*eblock.crypto_entry->finish_key)(&eblock);
krb5_free_kdc_rep(local_dec_rep);
free(scratch.data);
return retval;
}
#define clean_scratch() {bzero(scratch.data, scratch.length); free(scratch.data);}
if (retval = (*eblock.crypto_entry->finish_key)(&eblock)) {
krb5_free_kdc_rep(local_dec_rep);
clean_scratch();
return retval;
}
if (retval = decode_krb5_enc_kdc_rep_part(&scratch, &local_encpart)) {
krb5_free_kdc_rep(local_dec_rep);
clean_scratch();
return retval;
}
clean_scratch();
local_dec_rep->enc_part2 = local_encpart;
*dec_rep = local_dec_rep;
return 0;
}
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