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/*
* lib/krb5/krb/rd_rep.c
*
* Copyright 1990,1991 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. 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.
*
*
* krb5_rd_rep()
*/
#include "k5-int.h"
#include "auth_con.h"
/*
* Parses a KRB_AP_REP message, returning its contents.
*
* repl is filled in with with a pointer to allocated memory containing
* the fields from the encrypted response.
*
* the key in kblock is used to decrypt the message.
*
* returns system errors, encryption errors, replay errors
*/
KRB5_DLLIMP krb5_error_code KRB5_CALLCONV
krb5_rd_rep(context, auth_context, inbuf, repl)
krb5_context context;
krb5_auth_context auth_context;
const krb5_data FAR * inbuf;
krb5_ap_rep_enc_part FAR * FAR *repl;
{
krb5_error_code retval;
krb5_ap_rep * reply;
krb5_encrypt_block eblock;
krb5_data scratch;
if (!krb5_is_ap_rep(inbuf))
return KRB5KRB_AP_ERR_MSG_TYPE;
/* decode it */
if ((retval = decode_krb5_ap_rep(inbuf, &reply)))
return retval;
/* put together an eblock for this encryption */
if (!valid_enctype(reply->enc_part.enctype)) {
krb5_free_ap_rep(context, reply);
return KRB5_PROG_ETYPE_NOSUPP;
}
krb5_use_enctype(context, &eblock, reply->enc_part.enctype);
scratch.length = reply->enc_part.ciphertext.length;
if (!(scratch.data = malloc(scratch.length))) {
krb5_free_ap_rep(context, reply);
return(ENOMEM);
}
/* do any necessary key pre-processing */
if ((retval = krb5_process_key(context, &eblock,
auth_context->keyblock))) {
goto errout;
}
/* call the encryption routine */
if ((retval = krb5_decrypt(context,
(krb5_pointer) reply->enc_part.ciphertext.data,
(krb5_pointer) scratch.data,
scratch.length, &eblock, 0))) {
(void) krb5_finish_key(context, &eblock);
goto errout;
}
/* finished with the top-level encoding of the ap_rep */
if ((retval = krb5_finish_key(context, &eblock)))
goto clean_scratch;
/* now decode the decrypted stuff */
retval = decode_krb5_ap_rep_enc_part(&scratch, repl);
/* Check reply fields */
if (((*repl)->ctime != auth_context->authentp->ctime) ||
((*repl)->cusec != auth_context->authentp->cusec)) {
retval = KRB5_MUTUAL_FAILED;
goto clean_scratch;
}
/* Set auth subkey */
if ((*repl)->subkey) {
retval = krb5_copy_keyblock(context, (*repl)->subkey,
&auth_context->remote_subkey);
}
/* Get remote sequence number */
auth_context->remote_seq_number = (*repl)->seq_number;
clean_scratch:
memset(scratch.data, 0, scratch.length);
errout:
krb5_free_ap_rep(context, reply);
free(scratch.data);
return retval;
}
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