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
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
|
/*
* lib/krb5/krb/send_tgs.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. 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_send_tgs()
*/
#include "k5-int.h"
/*
Sends a request to the TGS and waits for a response.
options is used for the options in the KRB_TGS_REQ.
timestruct values are used for from, till, rtime " " "
enctype is used for enctype " " ", and to encrypt the authorization data,
sname is used for sname " " "
addrs, if non-NULL, is used for addresses " " "
authorization_dat, if non-NULL, is used for authorization_dat " " "
second_ticket, if required by options, is used for the 2nd ticket in the req.
in_cred is used for the ticket & session key in the KRB_AP_REQ header " " "
(the KDC realm is extracted from in_cred->server's realm)
The response is placed into *rep.
rep->response.data is set to point at allocated storage which should be
freed by the caller when finished.
returns system errors
*/
static krb5_error_code
krb5_send_tgs_basic(context, in_data, in_cred, outbuf)
krb5_context context;
krb5_data * in_data;
krb5_creds * in_cred;
krb5_data * outbuf;
{
krb5_error_code retval;
krb5_checksum checksum;
krb5_authenticator authent;
krb5_ap_req request;
krb5_encrypt_block eblock;
krb5_data * scratch;
krb5_data * toutbuf;
/* Generate checksum */
checksum.length = krb5_checksum_size(context, context->kdc_req_sumtype);
if ((checksum.contents = (krb5_octet *) malloc(checksum.length)) == NULL)
return(ENOMEM);
if ((retval = krb5_calculate_checksum(context, context->kdc_req_sumtype,
in_data->data, in_data->length,
(krb5_pointer) in_cred->keyblock.contents,
in_cred->keyblock.length,
&checksum))) {
free(checksum.contents);
return(retval);
}
/* gen authenticator */
authent.subkey = 0;
authent.seq_number = 0;
authent.checksum = &checksum;
authent.client = in_cred->client;
authent.authorization_data = in_cred->authdata;
if ((retval = krb5_us_timeofday(context, &authent.ctime,
&authent.cusec))) {
free(checksum.contents);
return(retval);
}
/* encode the authenticator */
if ((retval = encode_krb5_authenticator(&authent, &scratch))) {
free(checksum.contents);
return(retval);
}
free(checksum.contents);
request.authenticator.ciphertext.data = 0;
request.authenticator.kvno = 0;
request.ap_options = 0;
request.ticket = 0;
if ((retval = decode_krb5_ticket(&(in_cred)->ticket, &request.ticket)))
/* Cleanup scratch and scratch data */
goto cleanup_data;
/* put together an eblock for this encryption */
krb5_use_enctype(context, &eblock, in_cred->keyblock.enctype);
request.authenticator.enctype = in_cred->keyblock.enctype;
request.authenticator.ciphertext.length =
krb5_encrypt_size(scratch->length, eblock.crypto_entry);
/* add padding area, and zero it */
if (!(scratch->data = realloc(scratch->data,
request.authenticator.ciphertext.length))) {
/* may destroy scratch->data */
krb5_free_ticket(context, request.ticket);
retval = ENOMEM;
goto cleanup_scratch;
}
memset(scratch->data + scratch->length, 0,
request.authenticator.ciphertext.length - scratch->length);
if (!(request.authenticator.ciphertext.data =
malloc(request.authenticator.ciphertext.length))) {
retval = ENOMEM;
goto cleanup_ticket;
}
/* do any necessary key pre-processing */
if ((retval = krb5_process_key(context, &eblock, &(in_cred)->keyblock)))
goto cleanup;
/* call the encryption routine */
if ((retval=krb5_encrypt(context, (krb5_pointer) scratch->data,
(krb5_pointer)request.authenticator.ciphertext.data,
scratch->length, &eblock, 0))) {
krb5_finish_key(context, &eblock);
goto cleanup;
}
if ((retval = krb5_finish_key(context, &eblock)))
goto cleanup;
retval = encode_krb5_ap_req(&request, &toutbuf);
*outbuf = *toutbuf;
krb5_xfree(toutbuf);
cleanup:
memset(request.authenticator.ciphertext.data, 0,
request.authenticator.ciphertext.length);
free(request.authenticator.ciphertext.data);
cleanup_ticket:
krb5_free_ticket(context, request.ticket);
cleanup_data:
memset(scratch->data, 0, scratch->length);
free(scratch->data);
cleanup_scratch:
free(scratch);
return retval;
}
krb5_error_code
krb5_send_tgs(context, kdcoptions, timestruct, ktypes, sname, addrs,
authorization_data, padata, second_ticket, in_cred, rep)
krb5_context context;
const krb5_flags kdcoptions;
const krb5_ticket_times * timestruct;
const krb5_enctype * ktypes;
krb5_const_principal sname;
krb5_address * const * addrs;
krb5_authdata * const * authorization_data;
krb5_pa_data * const * padata;
const krb5_data * second_ticket;
krb5_creds * in_cred;
krb5_response * rep;
{
krb5_error_code retval;
krb5_kdc_req tgsreq;
krb5_data *scratch, scratch2;
krb5_ticket *sec_ticket = 0;
krb5_ticket *sec_ticket_arr[2];
krb5_timestamp time_now;
krb5_pa_data **combined_padata;
krb5_pa_data ap_req_padata;
/*
* in_creds MUST be a valid credential NOT just a partially filled in
* place holder for us to get credentials for the caller.
*/
if (!in_cred->ticket.length)
return(KRB5_NO_TKT_SUPPLIED);
memset((char *)&tgsreq, 0, sizeof(tgsreq));
tgsreq.kdc_options = kdcoptions;
tgsreq.server = (krb5_principal) sname;
tgsreq.from = timestruct->starttime;
tgsreq.till = timestruct->endtime;
tgsreq.rtime = timestruct->renew_till;
if ((retval = krb5_timeofday(context, &time_now)))
return(retval);
/* XXX we know they are the same size... */
rep->expected_nonce = tgsreq.nonce = (krb5_int32) time_now;
rep->request_time = time_now;
tgsreq.addresses = (krb5_address **) addrs;
if (authorization_data) {
/* need to encrypt it in the request */
krb5_encrypt_block eblock;
if ((retval = encode_krb5_authdata((const krb5_authdata**)authorization_data,
&scratch)))
return(retval);
krb5_use_enctype(context, &eblock, in_cred->keyblock.enctype);
tgsreq.authorization_data.enctype = in_cred->keyblock.enctype;
tgsreq.authorization_data.kvno = 0; /* ticket session key has */
/* no version */
tgsreq.authorization_data.ciphertext.length =
krb5_encrypt_size(scratch->length, eblock.crypto_entry);
/* add padding area, and zero it */
if (!(scratch->data = realloc(scratch->data,
tgsreq.authorization_data.ciphertext.length))) {
/* may destroy scratch->data */
krb5_xfree(scratch);
return ENOMEM;
}
memset(scratch->data + scratch->length, 0,
tgsreq.authorization_data.ciphertext.length - scratch->length);
if (!(tgsreq.authorization_data.ciphertext.data =
malloc(tgsreq.authorization_data.ciphertext.length))) {
krb5_free_data(context, scratch);
return ENOMEM;
}
if ((retval = krb5_process_key(context, &eblock,
&in_cred->keyblock))) {
krb5_free_data(context, scratch);
return retval;
}
/* call the encryption routine */
if ((retval = krb5_encrypt(context, (krb5_pointer) scratch->data,
(krb5_pointer) tgsreq.authorization_data.ciphertext.data,
scratch->length, &eblock, 0))) {
(void) krb5_finish_key(context, &eblock);
krb5_xfree(tgsreq.authorization_data.ciphertext.data);
krb5_free_data(context, scratch);
return retval;
}
krb5_free_data(context, scratch);
if ((retval = krb5_finish_key(context, &eblock))) {
krb5_xfree(tgsreq.authorization_data.ciphertext.data);
return retval;
}
}
/* Get the encryption types list */
if (ktypes) {
/* Check passed ktypes and make sure they're valid. */
for (tgsreq.nktypes = 0; ktypes[tgsreq.nktypes]; tgsreq.nktypes++) {
if (!valid_enctype(ktypes[tgsreq.nktypes]))
return KRB5_PROG_ETYPE_NOSUPP;
}
tgsreq.ktype = (krb5_enctype *)ktypes;
} else {
/* Get the default ktypes */
krb5_get_tgs_ktypes(context, sname, &(tgsreq.ktype));
for(tgsreq.nktypes = 0; tgsreq.ktype[tgsreq.nktypes]; tgsreq.nktypes++);
}
if (second_ticket) {
if ((retval = decode_krb5_ticket(second_ticket, &sec_ticket)))
goto send_tgs_error_1;
sec_ticket_arr[0] = sec_ticket;
sec_ticket_arr[1] = 0;
tgsreq.second_ticket = sec_ticket_arr;
} else
tgsreq.second_ticket = 0;
/* encode the body; then checksum it */
if ((retval = encode_krb5_kdc_req_body(&tgsreq, &scratch)))
goto send_tgs_error_2;
/*
* Get an ap_req.
*/
if ((retval = krb5_send_tgs_basic(context, scratch, in_cred, &scratch2))) {
krb5_free_data(context, scratch);
goto send_tgs_error_2;
}
krb5_free_data(context, scratch);
ap_req_padata.pa_type = KRB5_PADATA_AP_REQ;
ap_req_padata.length = scratch2.length;
ap_req_padata.contents = (krb5_octet *)scratch2.data;
/* combine in any other supplied padata */
if (padata) {
krb5_pa_data * const * counter;
register int i = 0;
for (counter = padata; *counter; counter++, i++);
combined_padata = (krb5_pa_data **)malloc(i+2);
if (!combined_padata) {
krb5_xfree(ap_req_padata.contents);
retval = ENOMEM;
goto send_tgs_error_2;
}
combined_padata[0] = &ap_req_padata;
for (i = 1, counter = padata; *counter; counter++, i++)
combined_padata[i] = (krb5_pa_data *) *counter;
combined_padata[i] = 0;
} else {
combined_padata = (krb5_pa_data **)malloc(2*sizeof(*combined_padata));
if (!combined_padata) {
krb5_xfree(ap_req_padata.contents);
retval = ENOMEM;
goto send_tgs_error_2;
}
combined_padata[0] = &ap_req_padata;
combined_padata[1] = 0;
}
tgsreq.padata = combined_padata;
/* the TGS_REQ is assembled in tgsreq, so encode it */
if ((retval = encode_krb5_tgs_req(&tgsreq, &scratch))) {
krb5_xfree(ap_req_padata.contents);
krb5_xfree(combined_padata);
goto send_tgs_error_2;
}
krb5_xfree(ap_req_padata.contents);
krb5_xfree(combined_padata);
/* now send request & get response from KDC */
retval = krb5_sendto_kdc(context, scratch,
krb5_princ_realm(context, sname),
&rep->response);
krb5_free_data(context, scratch);
if (retval == 0) {
if (krb5_is_tgs_rep(&rep->response))
rep->message_type = KRB5_TGS_REP;
else /* assume it's an error */
rep->message_type = KRB5_ERROR;
}
send_tgs_error_2:;
if (sec_ticket)
krb5_free_ticket(context, sec_ticket);
send_tgs_error_1:;
if (ktypes == NULL)
krb5_xfree(tgsreq.ktype);
if (tgsreq.authorization_data.ciphertext.data) {
memset(tgsreq.authorization_data.ciphertext.data, 0,
tgsreq.authorization_data.ciphertext.length);
krb5_xfree(tgsreq.authorization_data.ciphertext.data);
}
return retval;
}
|