summaryrefslogtreecommitdiff
path: root/source3/smbd/smb2_sesssetup.c
blob: faf7bd3db311b7dd886863424f5b7e8f89182330 (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
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
/*
   Unix SMB/CIFS implementation.
   Core SMB2 server

   Copyright (C) Stefan Metzmacher 2009

   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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "smbd/globals.h"
#include "../source4/libcli/smb2/smb2_constants.h"

static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *req,
					uint64_t in_session_id,
					uint8_t in_security_mode,
					DATA_BLOB in_security_buffer,
					uint16_t *out_session_flags,
					DATA_BLOB *out_security_buffer,
					uint64_t *out_session_id);

NTSTATUS smbd_smb2_request_process_sesssetup(struct smbd_smb2_request *req)
{
	const uint8_t *inhdr;
	const uint8_t *inbody;
	int i = req->current_idx;
	uint8_t *outhdr;
	DATA_BLOB outbody;
	DATA_BLOB outdyn;
	size_t expected_body_size = 0x19;
	size_t body_size;
	uint64_t in_session_id;
	uint8_t in_security_mode;
	uint16_t in_security_offset;
	uint16_t in_security_length;
	DATA_BLOB in_security_buffer;
	uint16_t out_session_flags;
	uint64_t out_session_id;
	uint16_t out_security_offset;
	DATA_BLOB out_security_buffer;
	NTSTATUS status;

	inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;

	if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
	}

	inbody = (const uint8_t *)req->in.vector[i+1].iov_base;

	body_size = SVAL(inbody, 0x00);
	if (body_size != expected_body_size) {
		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
	}

	in_security_offset = SVAL(inbody, 0x0C);
	in_security_length = SVAL(inbody, 0x0E);

	if (in_security_offset != (SMB2_HDR_BODY + (body_size & 0xFFFFFFFE))) {
		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
	}

	if (in_security_length > req->in.vector[i+2].iov_len) {
		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
	}

	in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);
	in_security_mode = CVAL(inbody, 0x03);
	in_security_buffer.data = (uint8_t *)req->in.vector[i+2].iov_base;
	in_security_buffer.length = in_security_length;

	status = smbd_smb2_session_setup(req,
					 in_session_id,
					 in_security_mode,
					 in_security_buffer,
					 &out_session_flags,
					 &out_security_buffer,
					 &out_session_id);
	if (!NT_STATUS_IS_OK(status) &&
	    !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
		status = nt_status_squash(status);
		return smbd_smb2_request_error(req, status);
	}

	out_security_offset = SMB2_HDR_BODY + 0x08;

	outhdr = (uint8_t *)req->out.vector[i].iov_base;

	outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
	if (outbody.data == NULL) {
		return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
	}

	SBVAL(outhdr, SMB2_HDR_SESSION_ID, out_session_id);

	SSVAL(outbody.data, 0x00, 0x08 + 1);	/* struct size */
	SSVAL(outbody.data, 0x02,
	      out_session_flags);		/* session flags */
	SSVAL(outbody.data, 0x04,
	      out_security_offset);		/* security buffer offset */
	SSVAL(outbody.data, 0x06,
	      out_security_buffer.length);	/* security buffer length */

	outdyn = out_security_buffer;

	return smbd_smb2_request_done_ex(req, status, outbody, &outdyn);
}

static int smbd_smb2_session_destructor(struct smbd_smb2_session *session)
{
	if (session->conn == NULL) {
		return 0;
	}

	/* first free all tcons */
	while (session->tcons.list) {
		talloc_free(session->tcons.list);
	}

	idr_remove(session->conn->smb2.sessions.idtree, session->vuid);
	DLIST_REMOVE(session->conn->smb2.sessions.list, session);

	session->vuid = 0;
	session->status = NT_STATUS_USER_SESSION_DELETED;
	session->conn = NULL;

	return 0;
}

static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *req,
					uint64_t in_session_id,
					uint8_t in_security_mode,
					DATA_BLOB in_security_buffer,
					uint16_t *out_session_flags,
					DATA_BLOB *out_security_buffer,
					uint64_t *out_session_id)
{
	struct smbd_smb2_session *session;
	NTSTATUS status;

	*out_session_flags = 0;
	*out_session_id = 0;

	if (in_session_id == 0) {
		int id;

		/* create a new session */
		session = talloc_zero(req->conn, struct smbd_smb2_session);
		if (session == NULL) {
			return NT_STATUS_NO_MEMORY;
		}
		session->status = NT_STATUS_MORE_PROCESSING_REQUIRED;
		id = idr_get_new_random(req->conn->smb2.sessions.idtree,
					session,
					req->conn->smb2.sessions.limit);
		if (id == -1) {
			return NT_STATUS_INSUFFICIENT_RESOURCES;
		}
		session->vuid = id;

		session->tcons.idtree = idr_init(session);
		if (session->tcons.idtree == NULL) {
			return NT_STATUS_NO_MEMORY;
		}
		session->tcons.limit = 0x0000FFFE;
		session->tcons.list = NULL;

		DLIST_ADD_END(req->conn->smb2.sessions.list, session,
			      struct smbd_smb2_session *);
		session->conn = req->conn;
		talloc_set_destructor(session, smbd_smb2_session_destructor);
	} else {
		void *p;

		/* lookup an existing session */
		p = idr_find(req->conn->smb2.sessions.idtree, in_session_id);
		if (p == NULL) {
			return NT_STATUS_USER_SESSION_DELETED;
		}
		session = talloc_get_type_abort(p, struct smbd_smb2_session);
	}

	if (NT_STATUS_IS_OK(session->status)) {
		return NT_STATUS_REQUEST_NOT_ACCEPTED;
	}

	if (session->auth_ntlmssp_state == NULL) {
		status = auth_ntlmssp_start(&session->auth_ntlmssp_state);
		if (!NT_STATUS_IS_OK(status)) {
			TALLOC_FREE(session);
			return status;
		}
	}

	if (in_security_buffer.data[0] == ASN1_APPLICATION(0)) {
		DATA_BLOB secblob_in;
		DATA_BLOB chal_out;
		char *kerb_mech = NULL;

		status = parse_spnego_mechanisms(in_security_buffer,
				&secblob_in, &kerb_mech);
		if (!NT_STATUS_IS_OK(status)) {
			TALLOC_FREE(session);
			return nt_status_squash(status);
		}

		/* For now, just SPNEGO NTLMSSP - krb5 goes here later.. */
		status = auth_ntlmssp_update(session->auth_ntlmssp_state,
					     secblob_in,
					     &chal_out);

		if (!NT_STATUS_IS_OK(status) &&
				!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
			auth_ntlmssp_end(&session->auth_ntlmssp_state);
			TALLOC_FREE(session);
			return nt_status_squash(status);
		}

		*out_security_buffer = spnego_gen_auth_response(&chal_out,
                                status, OID_NTLMSSP);

		*out_session_id = session->vuid;
		return status;
	} else if (in_security_buffer.data[0] == ASN1_CONTEXT(1)) {
		DATA_BLOB auth = data_blob_null;
		DATA_BLOB auth_out = data_blob_null;

		/* its an auth packet */
		if (!spnego_parse_auth(in_security_buffer, &auth)) {
			TALLOC_FREE(session);
			return NT_STATUS_LOGON_FAILURE;
		}
		/* For now, just SPNEGO NTLMSSP - krb5 goes here later.. */
		status = auth_ntlmssp_update(session->auth_ntlmssp_state,
					     auth,
					     &auth_out);
		if (!NT_STATUS_IS_OK(status)) {
			auth_ntlmssp_end(&session->auth_ntlmssp_state);
			TALLOC_FREE(session);
			return nt_status_squash(status);
		}

		*out_security_buffer = spnego_gen_auth_response(&auth_out,
                                status, NULL);

		*out_session_id = session->vuid;
	} else if (strncmp((char *)(in_security_buffer.data), "NTLMSSP", 7) == 0) {

		/* RAW NTLMSSP */
		status = auth_ntlmssp_update(session->auth_ntlmssp_state,
					     in_security_buffer,
					     out_security_buffer);

		if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
			*out_session_id = session->vuid;
			return status;
		}
		if (!NT_STATUS_IS_OK(status)) {
			auth_ntlmssp_end(&session->auth_ntlmssp_state);
			TALLOC_FREE(session);
			return nt_status_squash(status);
		}
		*out_session_id = session->vuid;
	}

	/* TODO: setup session key for signing */

	if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
	    lp_server_signing() == Required) {
		session->do_signing = true;
	}

	if (session->auth_ntlmssp_state->server_info->guest) {
		/* we map anonymous to guest internally */
		*out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
		*out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
		/* force no signing */
		session->do_signing = false;
	}

	session->server_info = session->auth_ntlmssp_state->server_info;
	data_blob_free(&session->server_info->user_session_key);
	session->server_info->user_session_key =
			data_blob_talloc(
			session->server_info,
			session->auth_ntlmssp_state->ntlmssp_state->session_key.data,
			session->auth_ntlmssp_state->ntlmssp_state->session_key.length);
	if (session->auth_ntlmssp_state->ntlmssp_state->session_key.length > 0) {
		if (session->server_info->user_session_key.data == NULL) {
			TALLOC_FREE(session);
			return NT_STATUS_NO_MEMORY;
		}
	}
	session->session_key = session->server_info->user_session_key;

	session->compat_vuser = talloc_zero(session, user_struct);
	if (session->compat_vuser == NULL) {
		TALLOC_FREE(session);
		return NT_STATUS_NO_MEMORY;
	}
	session->compat_vuser->auth_ntlmssp_state = session->auth_ntlmssp_state;
	session->compat_vuser->homes_snum = -1;
	session->compat_vuser->server_info = session->server_info;
	session->compat_vuser->session_keystr = NULL;
	session->compat_vuser->vuid = session->vuid;
	DLIST_ADD(session->conn->smb1.sessions.validated_users, session->compat_vuser);

	session->status = NT_STATUS_OK;

	/*
	 * we attach the session to the request
	 * so that the response can be signed
	 */
	req->session = session;
	if (session->do_signing) {
		req->do_signing = true;
	}

	*out_session_id = session->vuid;
	return status;
}

NTSTATUS smbd_smb2_request_check_session(struct smbd_smb2_request *req)
{
	const uint8_t *inhdr;
	int i = req->current_idx;
	uint64_t in_session_id;
	void *p;
	struct smbd_smb2_session *session;

	inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;

	in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);

	/* lookup an existing session */
	p = idr_find(req->conn->smb2.sessions.idtree, in_session_id);
	if (p == NULL) {
		return NT_STATUS_USER_SESSION_DELETED;
	}
	session = talloc_get_type_abort(p, struct smbd_smb2_session);

	if (!NT_STATUS_IS_OK(session->status)) {
		return NT_STATUS_ACCESS_DENIED;
	}

	set_current_user_info(session->server_info->sanitized_username,
			      session->server_info->unix_name,
			      pdb_get_domain(session->server_info->sam_account));

	req->session = session;
	return NT_STATUS_OK;
}

NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req)
{
	const uint8_t *inbody;
	int i = req->current_idx;
	DATA_BLOB outbody;
	size_t expected_body_size = 0x04;
	size_t body_size;

	if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
	}

	inbody = (const uint8_t *)req->in.vector[i+1].iov_base;

	body_size = SVAL(inbody, 0x00);
	if (body_size != expected_body_size) {
		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
	}

	/*
	 * TODO: cancel all outstanding requests on the session
	 *       and delete all tree connections.
	 */
	smbd_smb2_session_destructor(req->session);
	/*
	 * we may need to sign the response, so we need to keep
	 * the session until the response is sent to the wire.
	 */
	talloc_steal(req, req->session);

	outbody = data_blob_talloc(req->out.vector, NULL, 0x04);
	if (outbody.data == NULL) {
		return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
	}

	SSVAL(outbody.data, 0x00, 0x04);	/* struct size */
	SSVAL(outbody.data, 0x02, 0);		/* reserved */

	return smbd_smb2_request_done(req, outbody, NULL);
}