1/*
2   Unix SMB/CIFS implementation.
3   Core SMB2 server
4
5   Copyright (C) Stefan Metzmacher 2009
6
7   This program is free software; you can redistribute it and/or modify
8   it under the terms of the GNU General Public License as published by
9   the Free Software Foundation; either version 3 of the License, or
10   (at your option) any later version.
11
12   This program is distributed in the hope that it will be useful,
13   but WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   GNU General Public License for more details.
16
17   You should have received a copy of the GNU General Public License
18   along with this program.  If not, see <http://www.gnu.org/licenses/>.
19*/
20
21#include "includes.h"
22#include "smbd/globals.h"
23#include "../libcli/smb/smb_common.h"
24
25static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx,
26					      struct tevent_context *ev,
27					      struct smbd_smb2_request *smb2req,
28					      uint32_t in_smbpid,
29					      uint64_t in_file_id_volatile,
30					      uint32_t in_length,
31					      uint64_t in_offset,
32					      uint32_t in_minimum,
33					      uint32_t in_remaining);
34static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
35				    TALLOC_CTX *mem_ctx,
36				    DATA_BLOB *out_data,
37				    uint32_t *out_remaining);
38
39static void smbd_smb2_request_read_done(struct tevent_req *subreq);
40NTSTATUS smbd_smb2_request_process_read(struct smbd_smb2_request *req)
41{
42	const uint8_t *inhdr;
43	const uint8_t *inbody;
44	int i = req->current_idx;
45	size_t expected_body_size = 0x31;
46	size_t body_size;
47	uint32_t in_smbpid;
48	uint32_t in_length;
49	uint64_t in_offset;
50	uint64_t in_file_id_persistent;
51	uint64_t in_file_id_volatile;
52	uint32_t in_minimum_count;
53	uint32_t in_remaining_bytes;
54	struct tevent_req *subreq;
55
56	inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
57	if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
58		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
59	}
60
61	inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
62
63	body_size = SVAL(inbody, 0x00);
64	if (body_size != expected_body_size) {
65		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
66	}
67
68	in_smbpid = IVAL(inhdr, SMB2_HDR_PID);
69
70	in_length		= IVAL(inbody, 0x04);
71	in_offset		= BVAL(inbody, 0x08);
72	in_file_id_persistent	= BVAL(inbody, 0x10);
73	in_file_id_volatile	= BVAL(inbody, 0x18);
74	in_minimum_count	= IVAL(inbody, 0x20);
75	in_remaining_bytes	= IVAL(inbody, 0x28);
76
77	/* check the max read size */
78	if (in_length > 0x00010000) {
79		DEBUG(0,("here:%s: 0x%08X: 0x%08X\n",
80			__location__, in_length, 0x00010000));
81		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
82	}
83
84	if (req->compat_chain_fsp) {
85		/* skip check */
86	} else if (in_file_id_persistent != 0) {
87		return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
88	}
89
90	subreq = smbd_smb2_read_send(req,
91				     req->sconn->smb2.event_ctx,
92				     req,
93				     in_smbpid,
94				     in_file_id_volatile,
95				     in_length,
96				     in_offset,
97				     in_minimum_count,
98				     in_remaining_bytes);
99	if (subreq == NULL) {
100		return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
101	}
102	tevent_req_set_callback(subreq, smbd_smb2_request_read_done, req);
103
104	return smbd_smb2_request_pending_queue(req, subreq);
105}
106
107static void smbd_smb2_request_read_done(struct tevent_req *subreq)
108{
109	struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
110					struct smbd_smb2_request);
111	int i = req->current_idx;
112	uint8_t *outhdr;
113	DATA_BLOB outbody;
114	DATA_BLOB outdyn;
115	uint8_t out_data_offset;
116	DATA_BLOB out_data_buffer = data_blob_null;
117	uint32_t out_data_remaining = 0;
118	NTSTATUS status;
119	NTSTATUS error; /* transport error */
120
121	status = smbd_smb2_read_recv(subreq,
122				     req,
123				     &out_data_buffer,
124				     &out_data_remaining);
125	TALLOC_FREE(subreq);
126	if (!NT_STATUS_IS_OK(status)) {
127		error = smbd_smb2_request_error(req, status);
128		if (!NT_STATUS_IS_OK(error)) {
129			smbd_server_connection_terminate(req->sconn,
130							 nt_errstr(error));
131			return;
132		}
133		return;
134	}
135
136	out_data_offset = SMB2_HDR_BODY + 0x10;
137
138	outhdr = (uint8_t *)req->out.vector[i].iov_base;
139
140	outbody = data_blob_talloc(req->out.vector, NULL, 0x10);
141	if (outbody.data == NULL) {
142		error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
143		if (!NT_STATUS_IS_OK(error)) {
144			smbd_server_connection_terminate(req->sconn,
145							 nt_errstr(error));
146			return;
147		}
148		return;
149	}
150
151	SSVAL(outbody.data, 0x00, 0x10 + 1);	/* struct size */
152	SCVAL(outbody.data, 0x02,
153	      out_data_offset);			/* data offset */
154	SCVAL(outbody.data, 0x03, 0);		/* reserved */
155	SIVAL(outbody.data, 0x04,
156	      out_data_buffer.length);		/* data length */
157	SIVAL(outbody.data, 0x08,
158	      out_data_remaining);		/* data remaining */
159	SIVAL(outbody.data, 0x0C, 0);		/* reserved */
160
161	outdyn = out_data_buffer;
162
163	error = smbd_smb2_request_done(req, outbody, &outdyn);
164	if (!NT_STATUS_IS_OK(error)) {
165		smbd_server_connection_terminate(req->sconn,
166						 nt_errstr(error));
167		return;
168	}
169}
170
171struct smbd_smb2_read_state {
172	struct smbd_smb2_request *smb2req;
173	DATA_BLOB out_data;
174	uint32_t out_remaining;
175};
176
177static void smbd_smb2_read_pipe_done(struct tevent_req *subreq);
178
179static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx,
180					      struct tevent_context *ev,
181					      struct smbd_smb2_request *smb2req,
182					      uint32_t in_smbpid,
183					      uint64_t in_file_id_volatile,
184					      uint32_t in_length,
185					      uint64_t in_offset,
186					      uint32_t in_minimum,
187					      uint32_t in_remaining)
188{
189	struct tevent_req *req;
190	struct smbd_smb2_read_state *state;
191	struct smb_request *smbreq;
192	connection_struct *conn = smb2req->tcon->compat_conn;
193	files_struct *fsp;
194	ssize_t nread = -1;
195	struct lock_struct lock;
196
197	req = tevent_req_create(mem_ctx, &state,
198				struct smbd_smb2_read_state);
199	if (req == NULL) {
200		return NULL;
201	}
202	state->smb2req = smb2req;
203	state->out_data = data_blob_null;
204	state->out_remaining = 0;
205
206	DEBUG(10,("smbd_smb2_read: file_id[0x%016llX]\n",
207		  (unsigned long long)in_file_id_volatile));
208
209	smbreq = smbd_smb2_fake_smb_request(smb2req);
210	if (tevent_req_nomem(smbreq, req)) {
211		return tevent_req_post(req, ev);
212	}
213
214	fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
215	if (fsp == NULL) {
216		tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
217		return tevent_req_post(req, ev);
218	}
219	if (conn != fsp->conn) {
220		tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
221		return tevent_req_post(req, ev);
222	}
223	if (smb2req->session->vuid != fsp->vuid) {
224		tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
225		return tevent_req_post(req, ev);
226	}
227
228	state->out_data = data_blob_talloc(state, NULL, in_length);
229	if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) {
230		return tevent_req_post(req, ev);
231	}
232
233	if (IS_IPC(smbreq->conn)) {
234		struct tevent_req *subreq;
235
236		if (!fsp_is_np(fsp)) {
237			tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
238			return tevent_req_post(req, ev);
239		}
240
241		subreq = np_read_send(state, smbd_event_context(),
242				      fsp->fake_file_handle,
243				      state->out_data.data,
244				      state->out_data.length);
245		if (tevent_req_nomem(subreq, req)) {
246			return tevent_req_post(req, ev);
247		}
248		tevent_req_set_callback(subreq,
249					smbd_smb2_read_pipe_done,
250					req);
251		return req;
252	}
253
254	if (!CHECK_READ(fsp, smbreq)) {
255		tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED);
256		return tevent_req_post(req, ev);
257	}
258
259	init_strict_lock_struct(fsp,
260				in_smbpid,
261				in_offset,
262				in_length,
263				READ_LOCK,
264				&lock);
265
266	if (!SMB_VFS_STRICT_LOCK(conn, fsp, &lock)) {
267		tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
268		return tevent_req_post(req, ev);
269	}
270
271	nread = read_file(fsp,
272			  (char *)state->out_data.data,
273			  in_offset,
274			  in_length);
275
276	SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock);
277
278	if (nread < 0) {
279		DEBUG(5,("smbd_smb2_read: read_file[%s] nread[%lld]\n",
280			 fsp_str_dbg(fsp), (long long)nread));
281		tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED);
282		return tevent_req_post(req, ev);
283	}
284	if (nread == 0 && in_length != 0) {
285		DEBUG(5,("smbd_smb2_read: read_file[%s] end of file\n",
286			 fsp_str_dbg(fsp)));
287		tevent_req_nterror(req, NT_STATUS_END_OF_FILE);
288		return tevent_req_post(req, ev);
289	}
290
291	state->out_data.length = nread;
292	state->out_remaining = 0;
293	tevent_req_done(req);
294	return tevent_req_post(req, ev);
295}
296
297static void smbd_smb2_read_pipe_done(struct tevent_req *subreq)
298{
299	struct tevent_req *req = tevent_req_callback_data(subreq,
300				 struct tevent_req);
301	struct smbd_smb2_read_state *state = tevent_req_data(req,
302					     struct smbd_smb2_read_state);
303	NTSTATUS status;
304	ssize_t nread = -1;
305	bool is_data_outstanding;
306
307	status = np_read_recv(subreq, &nread, &is_data_outstanding);
308	TALLOC_FREE(subreq);
309	if (!NT_STATUS_IS_OK(status)) {
310		tevent_req_nterror(req, status);
311		return;
312	}
313
314	if (nread == 0 && state->out_data.length != 0) {
315		tevent_req_nterror(req, NT_STATUS_END_OF_FILE);
316		return;
317	}
318
319	state->out_data.length = nread;
320	state->out_remaining = 0;
321
322	tevent_req_done(req);
323}
324
325static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
326				    TALLOC_CTX *mem_ctx,
327				    DATA_BLOB *out_data,
328				    uint32_t *out_remaining)
329{
330	NTSTATUS status;
331	struct smbd_smb2_read_state *state = tevent_req_data(req,
332					     struct smbd_smb2_read_state);
333
334	if (tevent_req_is_nterror(req, &status)) {
335		tevent_req_received(req);
336		return status;
337	}
338
339	*out_data = state->out_data;
340	talloc_steal(mem_ctx, out_data->data);
341	*out_remaining = state->out_remaining;
342
343	tevent_req_received(req);
344	return NT_STATUS_OK;
345}
346