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
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
|
/*
Unix SMB/CIFS implementation.
kerberos utility library
Copyright (C) Andrew Tridgell 2001
Copyright (C) Remus Koos 2001
Copyright (C) Luke Howard 2003
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "includes.h"
#ifdef HAVE_KRB5
/*
verify an incoming ticket and parse out the principal name and
authorization_data if available
*/
NTSTATUS ads_verify_ticket(ADS_STRUCT *ads, const DATA_BLOB *ticket,
char **principal, DATA_BLOB *auth_data,
DATA_BLOB *ap_rep,
uint8 session_key[16])
{
krb5_context context;
krb5_auth_context auth_context = NULL;
krb5_keytab keytab = NULL;
krb5_data packet;
krb5_ticket *tkt = NULL;
int ret, i;
krb5_keyblock * key;
krb5_principal host_princ;
char *host_princ_s;
fstring myname;
char *password_s;
krb5_data password;
krb5_enctype *enctypes = NULL;
BOOL auth_ok = False;
if (!secrets_init()) {
DEBUG(1,("secrets_init failed\n"));
return NT_STATUS_LOGON_FAILURE;
}
password_s = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
if (!password_s) {
DEBUG(1,("failed to fetch machine password\n"));
return NT_STATUS_LOGON_FAILURE;
}
password.data = password_s;
password.length = strlen(password_s);
ret = krb5_init_context(&context);
if (ret) {
DEBUG(1,("krb5_init_context failed (%s)\n", error_message(ret)));
return NT_STATUS_LOGON_FAILURE;
}
ret = krb5_set_default_realm(context, ads->auth.realm);
if (ret) {
DEBUG(1,("krb5_set_default_realm failed (%s)\n", error_message(ret)));
return NT_STATUS_LOGON_FAILURE;
}
/* this whole process is far more complex than I would
like. We have to go through all this to allow us to store
the secret internally, instead of using /etc/krb5.keytab */
ret = krb5_auth_con_init(context, &auth_context);
if (ret) {
DEBUG(1,("krb5_auth_con_init failed (%s)\n", error_message(ret)));
return NT_STATUS_LOGON_FAILURE;
}
fstrcpy(myname, global_myname());
strlower(myname);
asprintf(&host_princ_s, "HOST/%s@%s", myname, lp_realm());
ret = krb5_parse_name(context, host_princ_s, &host_princ);
if (ret) {
DEBUG(1,("krb5_parse_name(%s) failed (%s)\n", host_princ_s, error_message(ret)));
return NT_STATUS_LOGON_FAILURE;
}
if (!(key = (krb5_keyblock *)malloc(sizeof(*key)))) {
return NT_STATUS_NO_MEMORY;
}
if ((ret = get_kerberos_allowed_etypes(context, &enctypes))) {
DEBUG(1,("krb5_get_permitted_enctypes failed (%s)\n",
error_message(ret)));
return NT_STATUS_LOGON_FAILURE;
}
/* we need to setup a auth context with each possible encoding type in turn */
for (i=0;enctypes[i];i++) {
if (create_kerberos_key_from_string(context, host_princ, &password, key, enctypes[i])) {
continue;
}
krb5_auth_con_setuseruserkey(context, auth_context, key);
packet.length = ticket->length;
packet.data = (krb5_pointer)ticket->data;
if (!(ret = krb5_rd_req(context, &auth_context, &packet,
NULL, keytab, NULL, &tkt))) {
free_kerberos_etypes(context, enctypes);
auth_ok = True;
break;
}
}
if (!auth_ok) {
DEBUG(3,("krb5_rd_req with auth failed (%s)\n",
error_message(ret)));
return NT_STATUS_LOGON_FAILURE;
}
ret = krb5_mk_rep(context, auth_context, &packet);
if (ret) {
DEBUG(3,("Failed to generate mutual authentication reply (%s)\n",
error_message(ret)));
krb5_auth_con_free(context, auth_context);
return NT_STATUS_LOGON_FAILURE;
}
*ap_rep = data_blob(packet.data, packet.length);
free(packet.data);
get_krb5_smb_session_key(context, auth_context, session_key);
#ifdef DEBUG_PASSWORD
DEBUG(10,("SMB session key (from ticket) follows:\n"));
dump_data(10, session_key, 16);
#endif
#if 0
file_save("/tmp/ticket.dat", ticket->data, ticket->length);
#endif
get_auth_data_from_tkt(auth_data, tkt);
{
TALLOC_CTX *ctx = talloc_init("pac data");
decode_pac_data(auth_data, ctx);
talloc_destroy(ctx);
}
#if 0
if (tkt->enc_part2) {
file_save("/tmp/authdata.dat",
tkt->enc_part2->authorization_data[0]->contents,
tkt->enc_part2->authorization_data[0]->length);
#endif
if ((ret = krb5_unparse_name(context, get_principal_from_tkt(tkt),
principal))) {
DEBUG(3,("krb5_unparse_name failed (%s)\n",
error_message(ret)));
data_blob_free(auth_data);
data_blob_free(ap_rep);
krb5_auth_con_free(context, auth_context);
return NT_STATUS_LOGON_FAILURE;
}
krb5_auth_con_free(context, auth_context);
return NT_STATUS_OK;
}
#endif /* HAVE_KRB5 */
|
