1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
/*
* 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. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* 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_error_code KRB5_CALLCONV
krb5_rd_rep(krb5_context context, krb5_auth_context auth_context,
const krb5_data *inbuf, krb5_ap_rep_enc_part **repl)
{
krb5_error_code retval;
krb5_ap_rep * reply;
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 */
scratch.length = reply->enc_part.ciphertext.length;
if (!(scratch.data = malloc(scratch.length))) {
krb5_free_ap_rep(context, reply);
return(ENOMEM);
}
if ((retval = krb5_c_decrypt(context, auth_context->keyblock,
KRB5_KEYUSAGE_AP_REP_ENCPART, 0,
&reply->enc_part, &scratch)))
goto clean_scratch;
/* now decode the decrypted stuff */
retval = decode_krb5_ap_rep_enc_part(&scratch, repl);
if (retval)
goto clean_scratch;
/* 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) {
if (auth_context->recv_subkey) {
krb5_free_keyblock(context, auth_context->recv_subkey);
auth_context->recv_subkey = NULL;
}
retval = krb5_copy_keyblock(context, (*repl)->subkey,
&auth_context->recv_subkey);
if (retval)
goto clean_scratch;
if (auth_context->send_subkey) {
krb5_free_keyblock(context, auth_context->send_subkey);
auth_context->send_subkey = NULL;
}
retval = krb5_copy_keyblock(context, (*repl)->subkey,
&auth_context->send_subkey);
if (retval) {
krb5_free_keyblock(context, auth_context->send_subkey);
auth_context->send_subkey = NULL;
}
}
/* Get remote sequence number */
auth_context->remote_seq_number = (*repl)->seq_number;
clean_scratch:
memset(scratch.data, 0, scratch.length);
krb5_free_ap_rep(context, reply);
free(scratch.data);
return retval;
}
|
