1 /* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */ 2 /* lib/krb5/krb/decode_kdc.c */ 3 /* 4 * Copyright 1990 by the Massachusetts Institute of Technology. 5 * All Rights Reserved. 6 * 7 * Export of this software from the United States of America may 8 * require a specific license from the United States Government. 9 * It is the responsibility of any person or organization contemplating 10 * export to obtain such a license before exporting. 11 * 12 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and 13 * distribute this software and its documentation for any purpose and 14 * without fee is hereby granted, provided that the above copyright 15 * notice appear in all copies and that both that copyright notice and 16 * this permission notice appear in supporting documentation, and that 17 * the name of M.I.T. not be used in advertising or publicity pertaining 18 * to distribution of the software without specific, written prior 19 * permission. Furthermore if you modify this software you must label 20 * your software as modified software and not distribute it in such a 21 * fashion that it might be confused with the original M.I.T. software. 22 * M.I.T. makes no representations about the suitability of 23 * this software for any purpose. It is provided "as is" without express 24 * or implied warranty. 25 */ 26 27 #include "k5-int.h" 28 #include "int-proto.h" 29 #include "fast.h" 30 31 /* 32 Takes a KDC_REP message and decrypts encrypted part using etype and 33 *key, putting result in *rep. 34 dec_rep->client,ticket,session,last_req,server,caddrs 35 are all set to allocated storage which should be freed by the caller 36 when finished with the response. 37 38 If the response isn't a KDC_REP (tgs or as), it returns an error from 39 the decoding routines. 40 41 returns errors from encryption routines, system errors 42 */ 43 44 krb5_error_code 45 krb5int_decode_tgs_rep(krb5_context context, 46 struct krb5int_fast_request_state *fast_state, 47 krb5_data *enc_rep, const krb5_keyblock *key, 48 krb5_keyusage usage, krb5_kdc_rep **dec_rep_out) 49 { 50 krb5_error_code retval; 51 krb5_kdc_rep *dec_rep = NULL; 52 krb5_keyblock *strengthen_key = NULL, tgs_key; 53 54 tgs_key.contents = NULL; 55 if (krb5_is_as_rep(enc_rep)) 56 retval = decode_krb5_as_rep(enc_rep, &dec_rep); 57 else if (krb5_is_tgs_rep(enc_rep)) 58 retval = decode_krb5_tgs_rep(enc_rep, &dec_rep); 59 else 60 retval = KRB5KRB_AP_ERR_MSG_TYPE; 61 if (retval) 62 goto cleanup; 63 64 retval = krb5int_fast_process_response(context, fast_state, dec_rep, 65 &strengthen_key); 66 if (retval == KRB5_ERR_FAST_REQUIRED) 67 retval = 0; 68 else if (retval) 69 goto cleanup; 70 retval = krb5int_fast_reply_key(context, strengthen_key, key, &tgs_key); 71 if (retval) 72 goto cleanup; 73 74 retval = krb5_kdc_rep_decrypt_proc(context, &tgs_key, &usage, dec_rep); 75 if (retval) 76 goto cleanup; 77 78 *dec_rep_out = dec_rep; 79 dec_rep = NULL; 80 81 cleanup: 82 krb5_free_kdc_rep(context, dec_rep); 83 krb5_free_keyblock(context, strengthen_key); 84 krb5_free_keyblock_contents(context, &tgs_key); 85 return retval; 86 } 87