summaryrefslogtreecommitdiff
path: root/source4/smb_server/smb2/negprot.c
blob: bc896aa9240869ee3112b38f4b6a39dda2d4c86a (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
/* 
   Unix SMB2 implementation.
   
   Copyright (C) Andrew Bartlett	2001-2005
   Copyright (C) Stefan Metzmacher	2005
   
   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 "auth/credentials/credentials.h"
#include "auth/auth.h"
#include "auth/gensec/gensec.h"
#include "libcli/raw/libcliraw.h"
#include "libcli/raw/raw_proto.h"
#include "libcli/smb2/smb2.h"
#include "libcli/smb2/smb2_calls.h"
#include "smb_server/smb_server.h"
#include "smb_server/smb2/smb2_server.h"
#include "smbd/service_stream.h"
#include "param/param.h"

static NTSTATUS smb2srv_negprot_secblob(struct smb2srv_request *req, DATA_BLOB *_blob)
{
	struct gensec_security *gensec_security;
	DATA_BLOB null_data_blob = data_blob(NULL, 0);
	DATA_BLOB blob;
	NTSTATUS nt_status;
	struct cli_credentials *server_credentials;

	server_credentials = cli_credentials_init(req);
	if (!server_credentials) {
		smbsrv_terminate_connection(req->smb_conn, "Failed to init server credentials\n");
		return NT_STATUS_NO_MEMORY;
	}

	cli_credentials_set_conf(server_credentials, req->smb_conn->lp_ctx);
	nt_status = cli_credentials_set_machine_account(server_credentials, req->smb_conn->lp_ctx);
	if (!NT_STATUS_IS_OK(nt_status)) {
		DEBUG(10, ("Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(nt_status)));
		talloc_free(server_credentials);
		server_credentials = NULL;
	}

	req->smb_conn->negotiate.server_credentials = talloc_steal(req->smb_conn, server_credentials);

	nt_status = samba_server_gensec_start(req,
					      req->smb_conn->connection->event.ctx,
					      req->smb_conn->connection->msg_ctx,
					      req->smb_conn->lp_ctx,
					      server_credentials,
					      "cifs",
					      &gensec_security);
	if (!NT_STATUS_IS_OK(nt_status)) {
		DEBUG(0, ("Failed to start GENSEC: %s\n", nt_errstr(nt_status)));
		smbsrv_terminate_connection(req->smb_conn, "Failed to start GENSEC\n");
		return nt_status;
	}

	gensec_set_target_service(gensec_security, "cifs");

	gensec_set_credentials(gensec_security, server_credentials);

	nt_status = gensec_start_mech_by_oid(gensec_security, GENSEC_OID_SPNEGO);
	if (!NT_STATUS_IS_OK(nt_status)) {
		DEBUG(0, ("Failed to start SPNEGO: %s\n", nt_errstr(nt_status)));
		smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO\n");
		return nt_status;
	}

	nt_status = gensec_update(gensec_security, req, null_data_blob, &blob);
	if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
		DEBUG(0, ("Failed to get SPNEGO to give us the first token: %s\n", nt_errstr(nt_status)));
		smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO - no first token\n");
		return nt_status;
	}

	*_blob = blob;
	return NT_STATUS_OK;
}

static NTSTATUS smb2srv_negprot_backend(struct smb2srv_request *req, struct smb2_negprot *io)
{
	NTSTATUS status;
	struct timeval current_time;
	struct timeval boot_time;
	uint16_t i;
	uint16_t dialect = 0;

	/* we only do one dialect for now */
	if (io->in.dialect_count < 1) {
		return NT_STATUS_NOT_SUPPORTED;
	}
	for (i=0; i < io->in.dialect_count; i++) {
		dialect = io->in.dialects[i];
		if (dialect == SMB2_DIALECT_REVISION_202) {
			break;
		}
	}
	if (dialect != SMB2_DIALECT_REVISION_202) {
		DEBUG(0,("Got unexpected SMB2 dialect %u\n", dialect));
		return NT_STATUS_NOT_SUPPORTED;
	}

	req->smb_conn->negotiate.protocol = PROTOCOL_SMB2_02;

	current_time = timeval_current(); /* TODO: handle timezone?! */
	boot_time = timeval_current(); /* TODO: fix me */

	ZERO_STRUCT(io->out);
	switch (lpcfg_server_signing(req->smb_conn->lp_ctx)) {
	case SMB_SIGNING_OFF:
		io->out.security_mode = 0;
		break;
	case SMB_SIGNING_SUPPORTED:
	case SMB_SIGNING_AUTO:
		io->out.security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED;
		break;
	case SMB_SIGNING_REQUIRED:
		io->out.security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED;
		/* force signing on immediately */
		req->smb_conn->smb2_signing_required = true;
		break;
	}
	io->out.dialect_revision   = dialect;
	io->out.capabilities       = 0;
	io->out.max_transact_size  = lpcfg_parm_ulong(req->smb_conn->lp_ctx, NULL,
						   "smb2", "max transaction size", 0x10000);
	io->out.max_read_size      = lpcfg_parm_ulong(req->smb_conn->lp_ctx, NULL,
						   "smb2", "max read size", 0x10000);
	io->out.max_write_size     = lpcfg_parm_ulong(req->smb_conn->lp_ctx, NULL,
						   "smb2", "max write size", 0x10000);
	io->out.system_time	   = timeval_to_nttime(&current_time);
	io->out.server_start_time  = timeval_to_nttime(&boot_time);
	io->out.reserved2          = 0;
	status = smb2srv_negprot_secblob(req, &io->out.secblob);
	NT_STATUS_NOT_OK_RETURN(status);

	return NT_STATUS_OK;
}

static void smb2srv_negprot_send(struct smb2srv_request *req, struct smb2_negprot *io)
{
	NTSTATUS status;

	if (NT_STATUS_IS_ERR(req->status)) {
		smb2srv_send_error(req, req->status); /* TODO: is this correct? */
		return;
	}

	status = smb2srv_setup_reply(req, 0x40, true, io->out.secblob.length);
	if (!NT_STATUS_IS_OK(status)) {
		smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
		talloc_free(req);
		return;
	}

	SSVAL(req->out.body, 0x02, io->out.security_mode);
	SIVAL(req->out.body, 0x04, io->out.dialect_revision);
	SIVAL(req->out.body, 0x06, io->out.reserved);
	status = smbcli_push_guid(req->out.body, 0x08, &io->out.server_guid);
	if (!NT_STATUS_IS_OK(status)) {
		smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
		talloc_free(req);
		return;
	}
	SIVAL(req->out.body, 0x18, io->out.capabilities);
	SIVAL(req->out.body, 0x1C, io->out.max_transact_size);
	SIVAL(req->out.body, 0x20, io->out.max_read_size);
	SIVAL(req->out.body, 0x24, io->out.max_write_size);
	push_nttime(req->out.body, 0x28, io->out.system_time);
	push_nttime(req->out.body, 0x30, io->out.server_start_time);
	SIVAL(req->out.body, 0x3C, io->out.reserved2);
	status = smb2_push_o16s16_blob(&req->out, 0x38, io->out.secblob);
	if (!NT_STATUS_IS_OK(status)) {
		smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
		talloc_free(req);
		return;
	}

	smb2srv_send_reply(req);
}

void smb2srv_negprot_recv(struct smb2srv_request *req)
{
	struct smb2_negprot *io;
	int i;

	if (req->in.body_size < 0x26) {
		smbsrv_terminate_connection(req->smb_conn, "Bad body size in SMB2 negprot");
		return;
	}

	io = talloc(req, struct smb2_negprot);
	if (!io) {
		smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
		talloc_free(req);
		return;
	}

	io->in.dialect_count = SVAL(req->in.body, 0x02);
	io->in.security_mode = SVAL(req->in.body, 0x04);
	io->in.reserved      = SVAL(req->in.body, 0x06);
	io->in.capabilities  = IVAL(req->in.body, 0x08);
	req->status = smbcli_pull_guid(req->in.body, 0xC, &io->in.client_guid);
	if (!NT_STATUS_IS_OK(req->status)) {
		smbsrv_terminate_connection(req->smb_conn, "Bad GUID in SMB2 negprot");
		talloc_free(req);
		return;
	}
	io->in.start_time = smbcli_pull_nttime(req->in.body, 0x1C);

	io->in.dialects = talloc_array(req, uint16_t, io->in.dialect_count);
	if (io->in.dialects == NULL) {
		smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
		talloc_free(req);
		return;
	}
	for (i=0;i<io->in.dialect_count;i++) {
		io->in.dialects[i] = SVAL(req->in.body, 0x24+i*2);
	}

	req->status = smb2srv_negprot_backend(req, io);

	if (req->control_flags & SMB2SRV_REQ_CTRL_FLAG_NOT_REPLY) {
		talloc_free(req);
		return;
	}
	smb2srv_negprot_send(req, io);
}

/*
 * reply to a SMB negprot request with dialect "SMB 2.002"
 */
void smb2srv_reply_smb_negprot(struct smbsrv_request *smb_req)
{
	struct smb2srv_request *req;
	uint32_t body_fixed_size = 0x26;

	req = talloc_zero(smb_req->smb_conn, struct smb2srv_request);
	if (!req) goto nomem;
	req->smb_conn		= smb_req->smb_conn;
	req->request_time	= smb_req->request_time;
	talloc_steal(req, smb_req);

	req->in.size      = NBT_HDR_SIZE+SMB2_HDR_BODY+body_fixed_size;
	req->in.allocated = req->in.size;
	req->in.buffer    = talloc_array(req, uint8_t, req->in.allocated);
	if (!req->in.buffer) goto nomem;
	req->in.hdr       = req->in.buffer + NBT_HDR_SIZE;
	req->in.body      = req->in.hdr + SMB2_HDR_BODY;
	req->in.body_size = body_fixed_size;
	req->in.dynamic   = NULL;

	smb2srv_setup_bufinfo(req);

	SIVAL(req->in.hdr, 0,				SMB2_MAGIC);
	SSVAL(req->in.hdr, SMB2_HDR_LENGTH,		SMB2_HDR_BODY);
	SSVAL(req->in.hdr, SMB2_HDR_EPOCH,		0);
	SIVAL(req->in.hdr, SMB2_HDR_STATUS,		0);
	SSVAL(req->in.hdr, SMB2_HDR_OPCODE,		SMB2_OP_NEGPROT);
	SSVAL(req->in.hdr, SMB2_HDR_CREDIT,		0);
	SIVAL(req->in.hdr, SMB2_HDR_FLAGS,		0);
	SIVAL(req->in.hdr, SMB2_HDR_NEXT_COMMAND,	0);
	SBVAL(req->in.hdr, SMB2_HDR_MESSAGE_ID,		0);
	SIVAL(req->in.hdr, SMB2_HDR_PID,		0);
	SIVAL(req->in.hdr, SMB2_HDR_TID,		0);
	SBVAL(req->in.hdr, SMB2_HDR_SESSION_ID,		0);
	memset(req->in.hdr+SMB2_HDR_SIGNATURE, 0, 16);

	/* this seems to be a bug, they use 0x24 but the length is 0x26 */
	SSVAL(req->in.body, 0x00, 0x24);

	SSVAL(req->in.body, 0x02, 1);
	memset(req->in.body+0x04, 0, 32);
	SSVAL(req->in.body, 0x24, SMB2_DIALECT_REVISION_202);

	smb2srv_negprot_recv(req);
	return;
nomem:
	smbsrv_terminate_connection(smb_req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
	talloc_free(req);
	return;
}