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
182
183
184
185
186
187
188
189
190
|
/*
* Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the Kungliga Tekniska
* Högskolan and its contributors.
*
* 4. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "krb_locl.h"
RCSID("$Id: get_ad_tkt.c,v 1.16 1997/05/30 17:43:34 bg Exp $");
/*
* get_ad_tkt obtains a new service ticket from Kerberos, using
* the ticket-granting ticket which must be in the ticket file.
* It is typically called by krb_mk_req() when the client side
* of an application is creating authentication information to be
* sent to the server side.
*
* get_ad_tkt takes four arguments: three pointers to strings which
* contain the name, instance, and realm of the service for which the
* ticket is to be obtained; and an integer indicating the desired
* lifetime of the ticket.
*
* It returns an error status if the ticket couldn't be obtained,
* or AD_OK if all went well. The ticket is stored in the ticket
* cache.
*
* The request sent to the Kerberos ticket-granting service looks
* like this:
*
* pkt->dat
*
* TEXT original contents of authenticator+ticket
* pkt->dat built in krb_mk_req call
*
* 4 bytes time_ws always 0 (?)
* char lifetime lifetime argument passed
* string service service name argument
* string sinstance service instance arg.
*
* See "prot.h" for the reply packet layout and definitions of the
* extraction macros like pkt_version(), pkt_msg_type(), etc.
*/
int
get_ad_tkt(char *service, char *sinstance, char *realm, int lifetime)
{
static KTEXT_ST pkt_st;
KTEXT pkt = & pkt_st; /* Packet to KDC */
static KTEXT_ST rpkt_st;
KTEXT rpkt = &rpkt_st; /* Returned packet */
CREDENTIALS cr;
char lrealm[REALM_SZ];
u_int32_t time_ws = 0;
int kerror;
unsigned char *p;
/*
* First check if we have a "real" TGT for the corresponding
* realm, if we don't, use ordinary inter-realm authentication.
*/
kerror = krb_get_cred(KRB_TICKET_GRANTING_TICKET, realm, realm, &cr);
if (kerror == KSUCCESS)
strncpy(lrealm, realm, REALM_SZ);
else
kerror = krb_get_tf_realm(TKT_FILE, lrealm);
if (kerror != KSUCCESS)
return(kerror);
/*
* Look for the session key (and other stuff we don't need)
* in the ticket file for krbtgt.realm@lrealm where "realm"
* is the service's realm (passed in "realm" argument) and
* lrealm is the realm of our initial ticket. If we don't
* have this, we will try to get it.
*/
if ((kerror = krb_get_cred(KRB_TICKET_GRANTING_TICKET,
realm, lrealm, &cr)) != KSUCCESS) {
/*
* If realm == lrealm, we have no hope, so let's not even try.
*/
if ((strncmp(realm, lrealm, REALM_SZ)) == 0)
return(AD_NOTGT);
else{
if ((kerror =
get_ad_tkt(KRB_TICKET_GRANTING_TICKET,
realm, lrealm, lifetime)) != KSUCCESS)
if (kerror == KDC_PR_UNKNOWN)
return(AD_INTR_RLM_NOTGT);
else
return(kerror);
if ((kerror = krb_get_cred(KRB_TICKET_GRANTING_TICKET,
realm, lrealm, &cr)) != KSUCCESS)
return(kerror);
}
}
/*
* Make up a request packet to the "krbtgt.realm@lrealm".
* Start by calling krb_mk_req() which puts ticket+authenticator
* into "pkt". Then tack other stuff on the end.
*/
kerror = krb_mk_req(pkt,
KRB_TICKET_GRANTING_TICKET,
realm,lrealm,0L);
if (kerror)
return(AD_NOTGT);
p = pkt->dat + pkt->length;
p += krb_put_int(time_ws, p, 4);
p += krb_put_int(lifetime, p, 1);
p += krb_put_nir(service, sinstance, NULL, p);
pkt->length = p - pkt->dat;
rpkt->length = 0;
/* Send the request to the local ticket-granting server */
if ((kerror = send_to_kdc(pkt, rpkt, realm))) return(kerror);
/* check packet version of the returned packet */
{
KTEXT_ST cip;
CREDENTIALS cred;
struct timeval tv;
kerror = kdc_reply_cipher(rpkt, &cip);
if(kerror != KSUCCESS)
return kerror;
encrypt_ktext(&cip, &cr.session, DES_DECRYPT);
kerror = kdc_reply_cred(&cip, &cred);
if(kerror != KSUCCESS)
return kerror;
if (strcmp(cred.service, service) || strcmp(cred.instance, sinstance) ||
strcmp(cred.realm, realm)) /* not what we asked for */
return INTK_ERR; /* we need a better code here XXX */
gettimeofday(&tv, NULL);
if (abs((int)(tv.tv_sec - cred.issue_date)) > CLOCK_SKEW) {
return RD_AP_TIME; /* XXX should probably be better code */
}
kerror = save_credentials(cred.service, cred.instance, cred.realm,
cred.session, cred.lifetime, cred.kvno,
&cred.ticket_st, tv.tv_sec);
return kerror;
}
}
|
