forked from msktutil/msktutil
-
Notifications
You must be signed in to change notification settings - Fork 0
/
krb5wrap.cpp
377 lines (323 loc) · 11.6 KB
/
krb5wrap.cpp
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
365
366
367
368
369
370
371
372
373
374
375
376
377
/*
*----------------------------------------------------------------------------
*
* krb5wrap.cpp
*
* (C) 2004-2006 Dan Perry (dperry@pppl.gov)
* (C) 2006 Brian Elliott Finley (finley@anl.gov)
* (C) 2009-2010 Doug Engert (deengert@anl.gov)
* (C) 2010 James Y Knight (foom@fuhm.net)
* (C) 2010-2013 Ken Dreyer <ktdreyer at ktdreyer.com>
* (C) 2012-2017 Mark Proehl <mark at mproehl.net>
* (C) 2012-2017 Olaf Flebbe <of at oflebbe.de>
* (C) 2013-2017 Daniel Kobras <d.kobras at science-computing.de>
*
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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*-----------------------------------------------------------------------------
*/
#include "msktutil.h"
void krb5_error_exit( const char *func, int err_code) {
v_error_exit("error_exit: krb5 function %s failed: %s", func, error_message(err_code));
}
void krb5_warn( const char *func, int err_code) {
fprintf( stderr, "Warning: krb5 function %s failed: %s", func, error_message(err_code));
}
#ifdef HEIMDAL
krb5_error_code krb5_free_keytab_entry_contents(krb5_context context,
krb5_keytab_entry *entry)
{
if (entry) {
krb5_free_principal(context, entry->principal);
if (entry->keyblock.keyvalue.data) {
memset(entry->keyblock.keyvalue.data,
0,
entry->keyblock.keyvalue.length);
free(entry->keyblock.keyvalue.data);
}
return 0;
}
return -1;
}
#endif
void
initialize_g_context() {
VERBOSE("Creating Kerberos context");
krb5_error_code ret = krb5_init_context(&g_context);
if (ret) {
krb5_error_exit("krb5_init_context", ret);
}
}
void
destroy_g_context() {
VERBOSE("Destroying Kerberos context");
krb5_free_context(g_context);
g_context = 0;
}
void KRB5CCache::initialize(KRB5Principal &principal)
{
krb5_error_code ret = krb5_cc_initialize(g_context,
m_ccache,
principal.get());
if (ret) {
throw KRB5Exception("krb5_cc_initialize", ret);
}
}
void KRB5CCache::store(KRB5Creds &creds)
{
krb5_error_code ret = krb5_cc_store_cred(g_context,
m_ccache,
creds.get());
if (ret) {
throw KRB5Exception("krb5_cc_store_cred", ret);
}
}
KRB5Creds::KRB5Creds(KRB5Principal &principal,
KRB5Keytab &keytab,
const char *tkt_service) : m_creds()
{
krb5_error_code ret =
krb5_get_init_creds_keytab(g_context,
&m_creds,
principal.get(),
keytab.get(),
0,
const_cast<char*>(tkt_service), NULL);
if (ret) {
throw KRB5Exception("krb5_get_init_creds_keytab", ret);
}
}
KRB5Creds::KRB5Creds(KRB5Principal &principal,
const std::string &password,
const char *tkt_service) : m_creds()
{
krb5_error_code ret =
krb5_get_init_creds_password(g_context,
&m_creds,
principal.get(),
const_cast<char*>(password.c_str()),
NULL,
NULL,
0,
const_cast<char*>(tkt_service),
NULL);
if (ret) {
throw KRB5Exception("krb5_get_init_creds_keytab", ret);
}
}
std::string KRB5Principal::name()
{
char *principal_string;
krb5_error_code ret = krb5_unparse_name(g_context,
m_princ,
&principal_string);
if (ret) {
throw KRB5Exception("krb5_unparse_name", ret);
}
std::string result(principal_string);
#ifdef HEIMDAL
krb5_xfree(principal_string);
#else
krb5_free_unparsed_name(g_context, principal_string);
#endif
return result;
}
void KRB5Keytab::addEntry(const KRB5Principal &princ,
krb5_kvno kvno,
krb5_keyblock &keyblock)
{
krb5_keytab_entry entry;
entry.principal = princ.get();
entry.vno = kvno;
#ifdef HEIMDAL
entry.keyblock = keyblock;
#else
entry.key = keyblock;
#endif
// avoid duplicate entries
(void) krb5_kt_remove_entry(g_context,
m_keytab,
&entry);
krb5_error_code ret = krb5_kt_add_entry(g_context,
m_keytab,
&entry);
if (ret) {
if (errno != 0) {
fprintf(stderr,"Error: keytab write error: %s\n", strerror(errno));
}
throw KRB5Exception("krb5_kt_add_entry failed", ret);
}
}
void KRB5Keytab::addEntry(const KRB5Principal &princ,
krb5_kvno kvno,
krb5_enctype enctype,
const std::string &password,
const std::string &salt)
{
krb5_keyblock keyblock;
#ifdef HEIMDAL
krb5_data pass_data;
krb5_salt salt_data;
salt_data.salttype = KRB5_PW_SALT;
salt_data.saltvalue.data = const_cast<char *>(salt.c_str());
salt_data.saltvalue.length = salt.length();
pass_data.data = const_cast<char *>(password.c_str());
pass_data.length = password.length();
krb5_error_code ret = krb5_string_to_key_data_salt(g_context,
enctype,
pass_data,
salt_data,
&keyblock);
if (ret) {
throw KRB5Exception("krb5_string_to_key_data_salt", ret);
}
#else
krb5_error_code ret;
krb5_data salt_data, pass_data;
krb5_data *saltparam = &salt_data;
krb5_data *s2kparams = NULL;
salt_data.data = const_cast<char *>(salt.c_str());
salt_data.length = salt.length();
pass_data.data = const_cast<char *>(password.c_str());
pass_data.length = password.length();
/* MIT Kerberos v1.17+ allows us to replace the supplied salt (guessed by
* heuristics) with proper salt info as returned by the KDC. We'll always
* fall back to the previous behaviour for backward compatibility.
*/
# if HAVE_KRB5_GET_ETYPE_INFO
krb5_get_init_creds_opt *opt = NULL;
ret = krb5_get_init_creds_opt_alloc(g_context, &opt);
if (ret) {
throw KRB5Exception("krb5_get_init_creds_opt_alloc", ret);
}
krb5_get_init_creds_opt_set_etype_list(opt, &enctype, 1);
krb5_enctype kdc_enctype;
krb5_data kdc_salt;
krb5_data kdc_s2kparams;
ret = krb5_get_etype_info(g_context,
princ.get(),
opt,
&kdc_enctype,
&kdc_salt,
&kdc_s2kparams);
krb5_get_init_creds_opt_free(g_context, opt);
/* We query info for a single enctype, so this test should only ever fail
* if the KDC returns ENCTYPE_NULL, indicating that the requested enctype
* is not supported on its end. At this point, we could refuse to add
* the requested enctype to the keytab. For consistency with previous
* behaviour, though, we just keep going and add an entry with the salt
* value supplied by the caller.
*/
if (!ret && kdc_enctype == enctype) {
s2kparams = (kdc_s2kparams.length > 0) ? &kdc_s2kparams : NULL;
saltparam = &kdc_salt;
}
# endif
ret = krb5_c_string_to_key_with_params(g_context,
enctype,
&pass_data,
saltparam,
s2kparams,
&keyblock);
if (s2kparams) {
krb5_free_data_contents(g_context, s2kparams);
}
if (saltparam != &salt_data) {
krb5_free_data_contents(g_context, saltparam);
}
if (ret) {
throw KRB5Exception("krb5_c_string_to_key_with_params", ret);
}
#endif
addEntry(princ, kvno, keyblock);
}
void KRB5Keytab::removeEntry(const KRB5Principal &princ,
krb5_kvno kvno,
krb5_enctype enctype)
{
krb5_keytab_entry entry;
entry.principal = princ.get();
entry.vno = kvno;
#ifdef HEIMDAL
entry.keyblock.keytype = enctype;
#else
entry.key.enctype = enctype;
#endif
krb5_error_code ret = krb5_kt_remove_entry(g_context,
m_keytab,
&entry);
if (ret) {
if (errno != 0) {
fprintf(stderr,"Error: keytab write error: %s\n", strerror(errno));
}
throw KRB5Exception("krb5_kt_remove_entry", ret);
}
}
KRB5Keytab::cursor::cursor(KRB5Keytab &keytab) : m_keytab(keytab),
m_cursor(),
m_entry(),
m_princ(),
m_ok(true)
{
memset(&m_entry, 0, sizeof(m_entry));
krb5_error_code ret = krb5_kt_start_seq_get(g_context,
m_keytab.m_keytab,
&m_cursor);
if (ret) {
m_ok = false;
}
}
KRB5Keytab::cursor::~cursor()
{
if (!m_ok) {
m_princ.reset_no_free(NULL);
return;
}
krb5_free_keytab_entry_contents(g_context, &m_entry);
memset(&m_entry, 0, sizeof(m_entry));
/* Tell m_princ to not free its contents! */
m_princ.reset_no_free(NULL);
krb5_error_code ret = krb5_kt_end_seq_get(g_context,
m_keytab.m_keytab,
&m_cursor);
if (ret) {
krb5_warn("krb5_kt_end_seq_get", ret);
}
}
void KRB5Keytab::cursor::reset()
{
if (!m_ok) {
return;
}
krb5_error_code ret = krb5_kt_start_seq_get(g_context,
m_keytab.m_keytab,
&m_cursor);
if (ret) {
m_ok = false;
}
}
bool KRB5Keytab::cursor::next()
{
if (!m_ok) {
return false;
}
krb5_free_keytab_entry_contents(g_context, &m_entry);
memset(&m_entry, 0, sizeof(m_entry));
krb5_error_code ret = krb5_kt_next_entry(g_context,
m_keytab.m_keytab,
&m_entry,
&m_cursor);
m_princ.reset_no_free(m_entry.principal);
return ret == 0;
}
krb5_context g_context = NULL;