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
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
/*
* lib/krb5/krb/rd_cred.c
*
* Copyright 1994 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. 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_cred()
*/
/* XXX This API is going to change; what's here isn't general enough! */
/* XXX Once we finalize the API, it should go into func-proto.h and */
/* into the API doc. */
#include <krb5/krb5.h>
#include <krb5/ext-proto.h>
#include <krb5/los-proto.h>
#include <krb5/asn1.h>
extern krb5_deltat krb5_clockskew;
#define in_clock_skew(date) (labs((date)-currenttime) < krb5_clockskew)
/* Decode the KRB-CRED message, and return creds */
krb5_error_code INTERFACE
krb5_rd_cred(context, inbuf, key, creds, sender_addr, recv_addr)
krb5_context context;
const krb5_data *inbuf;
const krb5_keyblock *key;
krb5_creds *creds; /* Filled in */
const krb5_address *sender_addr; /* optional */
const krb5_address *recv_addr; /* optional */
{
krb5_error_code retval;
krb5_encrypt_block eblock;
krb5_cred *credmsg;
krb5_cred_enc_part *credmsg_enc_part;
krb5_data *scratch;
krb5_timestamp currenttime;
if (!krb5_is_krb_cred(inbuf))
return KRB5KRB_AP_ERR_MSG_TYPE;
/* decode private message */
if (retval = decode_krb5_cred(inbuf, &credmsg)) {
return retval;
}
#define cleanup_credmsg() {(void)krb5_xfree(credmsg->enc_part.ciphertext.data); (void)krb5_xfree(credmsg);}
if (!(scratch = (krb5_data *) malloc(sizeof(*scratch)))) {
cleanup_credmsg();
return ENOMEM;
}
#define cleanup_scratch() {(void)memset(scratch->data, 0, scratch->length); (void)krb5_xfree(scratch->data);}
if (retval = encode_krb5_ticket(credmsg->tickets[0], &scratch)) {
cleanup_credmsg();
cleanup_scratch();
return(retval);
}
creds->ticket = *scratch;
if (!(creds->ticket.data = malloc(scratch->length))) {
krb5_xfree(creds->ticket.data);
return ENOMEM;
}
memcpy((char *)creds->ticket.data, (char *) scratch->data, scratch->length);
cleanup_scratch();
if (!valid_etype(credmsg->enc_part.etype)) {
cleanup_credmsg();
return KRB5_PROG_ETYPE_NOSUPP;
}
/* put together an eblock for this decryption */
krb5_use_cstype(context, &eblock, credmsg->enc_part.etype);
scratch->length = credmsg->enc_part.ciphertext.length;
if (!(scratch->data = malloc(scratch->length))) {
cleanup_credmsg();
return ENOMEM;
}
/* do any necessary key pre-processing */
if (retval = krb5_process_key(context, &eblock, key)) {
cleanup_credmsg();
cleanup_scratch();
return retval;
}
#define cleanup_prockey() {(void) krb5_finish_key(context, &eblock);}
/* call the decryption routine */
if (retval = krb5_decrypt(context, (krb5_pointer) credmsg->enc_part.ciphertext.data,
(krb5_pointer) scratch->data,
scratch->length, &eblock,
0)) {
cleanup_credmsg();
cleanup_scratch();
cleanup_prockey();
return retval;
}
/* cred message is now decrypted -- do some cleanup */
cleanup_credmsg();
if (retval = krb5_finish_key(context, &eblock)) {
cleanup_scratch();
return retval;
}
/* now decode the decrypted stuff */
if (retval = decode_krb5_enc_cred_part(scratch, &credmsg_enc_part)) {
cleanup_scratch();
return retval;
}
cleanup_scratch();
#define cleanup_mesg() {(void)krb5_xfree(credmsg_enc_part);}
if (retval = krb5_timeofday(context, ¤ttime)) {
cleanup_mesg();
return retval;
}
if (!in_clock_skew(credmsg_enc_part->timestamp)) {
cleanup_mesg();
return KRB5KRB_AP_ERR_SKEW;
}
if (sender_addr && credmsg_enc_part->s_address &&
!krb5_address_compare(context, sender_addr,
credmsg_enc_part->s_address)) {
cleanup_mesg();
return KRB5KRB_AP_ERR_BADADDR;
}
if (recv_addr && credmsg_enc_part->r_address &&
!krb5_address_compare(context, recv_addr,
credmsg_enc_part->r_address)) {
cleanup_mesg();
return KRB5KRB_AP_ERR_BADADDR;
}
if (credmsg_enc_part->r_address) {
krb5_address **our_addrs;
if (retval = krb5_os_localaddr(&our_addrs)) {
cleanup_mesg();
return retval;
}
if (!krb5_address_search(context, credmsg_enc_part->r_address,
our_addrs)) {
krb5_free_addresses(context, our_addrs);
cleanup_mesg();
return KRB5KRB_AP_ERR_BADADDR;
}
krb5_free_addresses(context, our_addrs);
}
if (retval = krb5_copy_principal(context, credmsg_enc_part->ticket_info[0]->client,
&creds->client)) {
return(retval);
}
if (retval = krb5_copy_principal(context, credmsg_enc_part->ticket_info[0]->server,
&creds->server)) {
return(retval);
}
if (retval =
krb5_copy_keyblock_contents(context, credmsg_enc_part->ticket_info[0]->session,
&creds->keyblock)) {
return(retval);
}
creds->keyblock.magic = KV5M_KEYBLOCK;
creds->keyblock.etype = credmsg->tickets[0]->enc_part.etype;
#undef clean
#define clean() {\
memset((char *)creds->keyblock.contents, 0, creds->keyblock.length);}
creds->times = credmsg_enc_part->ticket_info[0]->times;
creds->is_skey = FALSE;
creds->ticket_flags = credmsg_enc_part->ticket_info[0]->flags;
if (retval = krb5_copy_addresses(context, credmsg_enc_part->ticket_info[0]->caddrs,
&creds->addresses)) {
clean();
return(retval);
}
creds->second_ticket.length = 0;
creds->authdata = 0;
cleanup_mesg();
return 0;
#undef clean
#undef cleanup_credmsg
#undef cleanup_scratch
#undef cleanup_prockey
#undef cleanup_mesg
}
|
