summaryrefslogtreecommitdiff
path: root/source4/libcli/auth/gensec_gssapi.c
blob: 43113412f722c40c0418656e3322f1a479c06c24 (plain)
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
378
/* 
   Unix SMB/CIFS implementation.

   Kerberos backend for GENSEC
   
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004

   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"
#include "system/kerberos.h"
#include "system/time.h"
#include "libcli/auth/kerberos.h"
#include "auth/auth.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_AUTH

struct gensec_gssapi_state {
	gss_ctx_id_t gssapi_context;
	struct gss_channel_bindings_struct *input_chan_bindings;
	gss_name_t server_name;
	gss_name_t client_name;
	OM_uint32 want_flags, got_flags;
	const gss_OID_desc *gss_oid;
};
static int gensec_gssapi_destory(void *ptr) 
{
	struct gensec_gssapi_state *gensec_gssapi_state = ptr;
	OM_uint32 maj_stat, min_stat;

	if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
		maj_stat = gss_delete_sec_context (&min_stat,
						   &gensec_gssapi_state->gssapi_context,
						   GSS_C_NO_BUFFER);
	}

	if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
		maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
	}
	if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
		maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
	}
	return 0;
}

static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
{
	struct gensec_gssapi_state *gensec_gssapi_state;

	gensec_gssapi_state = talloc(gensec_security, struct gensec_gssapi_state);
	if (!gensec_gssapi_state) {
		return NT_STATUS_NO_MEMORY;
	}

	gensec_security->private_data = gensec_gssapi_state;

	gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
	gensec_gssapi_state->server_name = GSS_C_NO_NAME;
	gensec_gssapi_state->client_name = GSS_C_NO_NAME;

	talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destory); 

	/* TODO: Fill in channel bindings */
	gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
	
	gensec_gssapi_state->want_flags = 0;
	gensec_gssapi_state->got_flags = 0;

	if (gensec_security->want_features & GENSEC_FEATURE_SESSION_KEY) {
		/* GSSAPI won't give us the session keys */
		return NT_STATUS_INVALID_PARAMETER;
	}
	if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
		gensec_gssapi_state->want_flags |= GSS_C_INTEG_FLAG;
	}
	if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
		gensec_gssapi_state->want_flags |= GSS_C_CONF_FLAG;
	}

	if (strcmp(gensec_security->ops->oid, GENSEC_OID_KERBEROS5) == 0) {
		static const gss_OID_desc gensec_gss_krb5_mechanism_oid_desc =
			{9, (void *)discard_const_p(char, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02")};

		gensec_gssapi_state->gss_oid = &gensec_gss_krb5_mechanism_oid_desc;
	} else if (strcmp(gensec_security->ops->oid, GENSEC_OID_SPNEGO) == 0) {
		static const gss_OID_desc gensec_gss_spnego_mechanism_oid_desc =
			{6, (void *)discard_const_p(char, "\x2b\x06\x01\x05\x05\x02")};
		gensec_gssapi_state->gss_oid = &gensec_gss_spnego_mechanism_oid_desc;
	} else {
		return NT_STATUS_INVALID_PARAMETER;
	}

	return NT_STATUS_OK;
}

static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
{
	NTSTATUS nt_status;
	struct gensec_gssapi_state *gensec_gssapi_state;

	nt_status = gensec_gssapi_start(gensec_security);
	if (!NT_STATUS_IS_OK(nt_status)) {
		return nt_status;
	}

	gensec_gssapi_state = gensec_security->private_data;

	return NT_STATUS_OK;
}

static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
{
	struct gensec_gssapi_state *gensec_gssapi_state;
	NTSTATUS nt_status;
	gss_buffer_desc name_token;
	OM_uint32 maj_stat, min_stat;

	gss_OID_desc hostbased = {10, 
				  (void *)discard_const_p(char, "\x2a\x86\x48\x86\xf7\x12"
							  "\x01\x02\x01\x04")};

	nt_status = gensec_gssapi_start(gensec_security);
	if (!NT_STATUS_IS_OK(nt_status)) {
		return nt_status;
	}

	gensec_gssapi_state = gensec_security->private_data;

	name_token.value = talloc_asprintf(gensec_gssapi_state, "%s@%s", gensec_get_target_service(gensec_security), 
					   gensec_get_target_hostname(gensec_security));
	DEBUG(0, ("name: %s\n", (char *)name_token.value));
	name_token.length = strlen(name_token.value);

	maj_stat = gss_import_name (&min_stat,
				    &name_token,
				    &hostbased,
				    &gensec_gssapi_state->server_name);


	if (maj_stat) {
		return NT_STATUS_UNSUCCESSFUL;
	}
	return NT_STATUS_OK;
}



/**
 * Next state function for the GSSAPI GENSEC mechanism
 * 
 * @param gensec_gssapi_state GSSAPI State
 * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 * @param in The request, as a DATA_BLOB
 * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent, 
 *                or NT_STATUS_OK if the user is authenticated. 
 */

static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security, 
				   TALLOC_CTX *out_mem_ctx, 
				   const DATA_BLOB in, DATA_BLOB *out) 
{
	struct gensec_gssapi_state *gensec_gssapi_state = gensec_security->private_data;
	NTSTATUS nt_status = NT_STATUS_UNSUCCESSFUL;
	OM_uint32 maj_stat, min_stat;
	OM_uint32 min_stat2;
	gss_buffer_desc input_token, output_token;
	gss_OID gss_oid_p;
	input_token.length = in.length;
	input_token.value = in.data;

	switch (gensec_security->gensec_role) {
	case GENSEC_CLIENT:
	{
		maj_stat = gss_init_sec_context(&min_stat, 
						GSS_C_NO_CREDENTIAL, 
						&gensec_gssapi_state->gssapi_context, 
						gensec_gssapi_state->server_name, 
						discard_const_p(gss_OID_desc, gensec_gssapi_state->gss_oid),
						gensec_gssapi_state->want_flags, 
						0, 
						gensec_gssapi_state->input_chan_bindings,
						&input_token, 
						NULL, 
						&output_token, 
						&gensec_gssapi_state->got_flags, /* ret flags */
						NULL);
		break;
	}
	case GENSEC_SERVER:
	{
		maj_stat = gss_accept_sec_context(&min_stat, 
						  &gensec_gssapi_state->gssapi_context, 
						  GSS_C_NO_CREDENTIAL, 
						  &input_token, 
						  gensec_gssapi_state->input_chan_bindings,
						  &gensec_gssapi_state->client_name, 
						  &gss_oid_p,
						  &output_token, 
						  &gensec_gssapi_state->got_flags, 
						  NULL, 
						  NULL);
		gensec_gssapi_state->gss_oid = gss_oid_p;
		break;
	}
	default:
		return NT_STATUS_INVALID_PARAMETER;
		
	}

	*out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
	gss_release_buffer(&min_stat2, &output_token);

	if (maj_stat == GSS_S_COMPLETE) {
		return NT_STATUS_OK;
	} else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
		return NT_STATUS_MORE_PROCESSING_REQUIRED;
	} else {
		gss_buffer_desc msg1, msg2;
		OM_uint32 msg_ctx = 0;
		
		msg1.value = NULL;
		msg2.value = NULL;
		gss_display_status(&min_stat2, maj_stat, GSS_C_GSS_CODE,
				   GSS_C_NULL_OID, &msg_ctx, &msg1);
		gss_display_status(&min_stat2, min_stat, GSS_C_MECH_CODE,
				   GSS_C_NULL_OID, &msg_ctx, &msg2);
		DEBUG(1, ("gensec_gssapi_update: %s : %s\n", (char *)msg1.value, (char *)msg2.value));
		gss_release_buffer(&min_stat2, &msg1);
		gss_release_buffer(&min_stat2, &msg2);

		return nt_status;
	}
	
}

static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security, 
				   TALLOC_CTX *mem_ctx, 
				   const DATA_BLOB *in, 
				   DATA_BLOB *out)
{
	struct gensec_gssapi_state *gensec_gssapi_state = gensec_security->private_data;
	OM_uint32 maj_stat, min_stat;
	gss_buffer_desc input_token, output_token;
	int conf_state;
	input_token.length = in->length;
	input_token.value = in->data;
	
	maj_stat = gss_wrap(&min_stat, 
			    gensec_gssapi_state->gssapi_context, 
			    gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
			    GSS_C_QOP_DEFAULT,
			    &input_token,
			    &conf_state,
			    &output_token);
	if (GSS_ERROR(maj_stat)) {
		return NT_STATUS_ACCESS_DENIED;
	}
	*out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);

	gss_release_buffer(&min_stat, &output_token);

	if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
	    && !conf_state) {
		return NT_STATUS_ACCESS_DENIED;
	}
	return NT_STATUS_OK;
}

static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security, 
				     TALLOC_CTX *mem_ctx, 
				     const DATA_BLOB *in, 
				     DATA_BLOB *out)
{
	struct gensec_gssapi_state *gensec_gssapi_state = gensec_security->private_data;
	OM_uint32 maj_stat, min_stat;
	gss_buffer_desc input_token, output_token;
	int conf_state;
	gss_qop_t qop_state;
	input_token.length = in->length;
	input_token.value = in->data;
	
	maj_stat = gss_unwrap(&min_stat, 
			      gensec_gssapi_state->gssapi_context, 
			      &input_token,
			      &output_token, 
			      &conf_state,
			      &qop_state);
	if (GSS_ERROR(maj_stat)) {
		return NT_STATUS_ACCESS_DENIED;
	}
	*out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);

	gss_release_buffer(&min_stat, &output_token);
	
	if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
	    && !conf_state) {
		return NT_STATUS_ACCESS_DENIED;
	}
	return NT_STATUS_OK;
}

static BOOL gensec_gssapi_have_feature(struct gensec_security *gensec_security, 
				       uint32 feature) 
{
	struct gensec_gssapi_state *gensec_gssapi_state = gensec_security->private_data;
	if (feature & GENSEC_FEATURE_SIGN) {
		return gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG;
	}
	if (feature & GENSEC_FEATURE_SEAL) {
		return gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG;
	}
	return False;
}

/* As a server, this could in theory accept any GSSAPI mech */
static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
	.name		= "gssapi_krb5",
	.sasl_name	= "GSSAPI",
	.oid            = GENSEC_OID_KERBEROS5,
	.client_start   = gensec_gssapi_client_start,
	.server_start   = gensec_gssapi_server_start,
	.update 	= gensec_gssapi_update,
	.wrap           = gensec_gssapi_wrap,
	.unwrap         = gensec_gssapi_unwrap,
	.have_feature   = gensec_gssapi_have_feature,
	.enabled        = False

};

static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
	.name		= "gssapi_spnego",
	.sasl_name	= "GSS-SPNEGO",
	.oid            = GENSEC_OID_SPNEGO,
	.client_start   = gensec_gssapi_client_start,
	.server_start   = gensec_gssapi_server_start,
	.update 	= gensec_gssapi_update,
	.wrap           = gensec_gssapi_wrap,
	.unwrap         = gensec_gssapi_unwrap,
	.have_feature   = gensec_gssapi_have_feature,
	.enabled        = False
};

NTSTATUS gensec_gssapi_init(void)
{
	NTSTATUS ret;

	ret = gensec_register(&gensec_gssapi_krb5_security_ops);
	if (!NT_STATUS_IS_OK(ret)) {
		DEBUG(0,("Failed to register '%s' gensec backend!\n",
			gensec_gssapi_krb5_security_ops.name));
		return ret;
	}

	ret = gensec_register(&gensec_gssapi_spnego_security_ops);
	if (!NT_STATUS_IS_OK(ret)) {
		DEBUG(0,("Failed to register '%s' gensec backend!\n",
			gensec_gssapi_spnego_security_ops.name));
		return ret;
	}

	return ret;
}