1 /*
2  * lib/krb5/krb/kdc_rep_dc.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  * krb5_kdc_rep_decrypt_proc()
28  */
29 
30 #include "k5-int.h"
31 
32 /*
33  * Decrypt the encrypted portion of the KDC_REP message, using the key
34  * passed.
35  *
36  */
37 
38 /*ARGSUSED*/
39 krb5_error_code
krb5_kdc_rep_decrypt_proc(krb5_context context,const krb5_keyblock * key,krb5_const_pointer decryptarg,krb5_kdc_rep * dec_rep)40 krb5_kdc_rep_decrypt_proc(krb5_context context, const krb5_keyblock *key, krb5_const_pointer decryptarg, krb5_kdc_rep *dec_rep)
41 {
42     krb5_error_code retval;
43     krb5_data scratch;
44     krb5_enc_kdc_rep_part *local_encpart;
45     krb5_keyusage usage;
46 
47     if (decryptarg) {
48 	usage = *(const krb5_keyusage *) decryptarg;
49     } else {
50 	usage = KRB5_KEYUSAGE_AS_REP_ENCPART;
51     }
52 
53     /* set up scratch decrypt/decode area */
54 
55     scratch.length = dec_rep->enc_part.ciphertext.length;
56     if (!(scratch.data = malloc(dec_rep->enc_part.ciphertext.length))) {
57 	return(ENOMEM);
58     }
59 
60     /*dec_rep->enc_part.enctype;*/
61 
62     if ((retval = krb5_c_decrypt(context, key, usage, 0, &dec_rep->enc_part,
63 				 &scratch))) {
64 	free(scratch.data);
65 	return(retval);
66     }
67 
68 #define clean_scratch() {memset(scratch.data, 0, scratch.length); \
69 free(scratch.data);}
70 
71     /* and do the decode */
72     retval = decode_krb5_enc_kdc_rep_part(&scratch, &local_encpart);
73     clean_scratch();
74     if (retval)
75 	return retval;
76 
77     dec_rep->enc_part2 = local_encpart;
78 
79     return 0;
80 }
81