1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright 2020 Tintri by DDN, Inc. All rights reserved.
14  */
15 
16 /*
17  * Dispatch function for SMB2_WRITE
18  */
19 
20 #include <smbsrv/smb2_kproto.h>
21 #include <smbsrv/smb_fsops.h>
22 
23 boolean_t smb_allow_unbuffered = B_TRUE;
24 
25 smb_sdrc_t
smb2_write(smb_request_t * sr)26 smb2_write(smb_request_t *sr)
27 {
28 	smb_rw_param_t *param = NULL;
29 	smb_ofile_t *of = NULL;
30 	smb_vdb_t *vdb = NULL;
31 	uint16_t StructSize;
32 	uint16_t DataOff;
33 	uint32_t Length;
34 	uint64_t Offset;
35 	smb2fid_t smb2fid;
36 	uint32_t Channel;
37 	uint32_t Remaining;
38 	uint16_t ChanInfoOffset;
39 	uint16_t ChanInfoLength;
40 	uint32_t Flags;
41 	uint32_t XferCount;
42 	uint32_t status;
43 	int data_chain_off, skip;
44 	int stability = 0;
45 	int rc = 0;
46 	boolean_t unbuffered = B_FALSE;
47 
48 	/*
49 	 * Decode SMB2 Write request
50 	 */
51 	rc = smb_mbc_decodef(
52 	    &sr->smb_data,
53 	    "wwlqqqllwwl",
54 	    &StructSize,		/* w */
55 	    &DataOff,			/* w */
56 	    &Length,			/* l */
57 	    &Offset,			/* q */
58 	    &smb2fid.persistent,	/* q */
59 	    &smb2fid.temporal,		/* q */
60 	    &Channel,			/* l */
61 	    &Remaining,			/* l */
62 	    &ChanInfoOffset,		/* w */
63 	    &ChanInfoLength,		/* w */
64 	    &Flags);			/* l */
65 	if (rc)
66 		return (SDRC_ERROR);
67 	if (StructSize != 49)
68 		return (SDRC_ERROR);
69 
70 	/*
71 	 * Setup an smb_rw_param_t which contains the VDB we need.
72 	 * This is automatically free'd.
73 	 */
74 	param = smb_srm_zalloc(sr, sizeof (*param));
75 	param->rw_offset = Offset;
76 	param->rw_count = Length;
77 	/* Note that the dtrace provider uses sr->arg.rw */
78 	sr->arg.rw = param;
79 
80 	/*
81 	 * Skip any padding before the write data.
82 	 */
83 	data_chain_off = sr->smb2_cmd_hdr + DataOff;
84 	skip = data_chain_off - sr->smb_data.chain_offset;
85 	if (skip < 0)
86 		return (SDRC_ERROR);
87 	if (skip > 0)
88 		(void) smb_mbc_decodef(&sr->smb_data, "#.", skip);
89 
90 	/*
91 	 * Decode the write data (payload)
92 	 */
93 	if (Length > smb2_max_rwsize)
94 		return (SDRC_ERROR);
95 	vdb = &param->rw_vdb;
96 	rc = smb_mbc_decodef(&sr->smb_data, "#B", Length, vdb);
97 	if (rc != 0 || vdb->vdb_len != Length)
98 		return (SDRC_ERROR);
99 	vdb->vdb_uio.uio_loffset = (offset_t)Offset;
100 
101 	/*
102 	 * Want FID lookup before the start probe.
103 	 */
104 	status = smb2sr_lookup_fid(sr, &smb2fid);
105 	of = sr->fid_ofile;
106 
107 	DTRACE_SMB2_START(op__Write, smb_request_t *, sr); /* arg.rw */
108 
109 	if (status)
110 		goto errout; /* Bad FID */
111 
112 
113 	XferCount = 0;
114 	if (Length == 0)
115 		goto errout;
116 
117 	/*
118 	 * Unbuffered refers to the MS-FSA Write argument by the same name.
119 	 * It indicates that the cache for this range should be flushed to disk,
120 	 * and data written directly to disk, bypassing the cache.
121 	 * We don't allow that degree of cache management.
122 	 * Translate this directly as FSYNC,
123 	 * which should at least flush the cache.
124 	 */
125 
126 	if (smb_allow_unbuffered &&
127 	    (Flags & SMB2_WRITEFLAG_WRITE_UNBUFFERED) != 0)
128 		unbuffered = B_TRUE;
129 
130 	switch (of->f_tree->t_res_type & STYPE_MASK) {
131 	case STYPE_DISKTREE:
132 	case STYPE_PRINTQ:
133 		if (!smb_node_is_dir(of->f_node)) {
134 			/* Check for conflicting locks. */
135 			rc = smb_lock_range_access(sr, of->f_node,
136 			    Offset, Length, B_TRUE);
137 			if (rc) {
138 				rc = ERANGE;
139 				break;
140 			}
141 		}
142 
143 		if (unbuffered || (Flags & SMB2_WRITEFLAG_WRITE_THROUGH) != 0 ||
144 		    (of->f_node->flags & NODE_FLAGS_WRITE_THROUGH) != 0) {
145 			stability = FSYNC;
146 		}
147 		rc = smb_fsop_write(sr, of->f_cr, of->f_node, of,
148 		    &vdb->vdb_uio, &XferCount, stability);
149 		if (rc)
150 			break;
151 		/* This revokes read cache delegations. */
152 		(void) smb_oplock_break_WRITE(of->f_node, of);
153 		break;
154 
155 	case STYPE_IPC:
156 		if (unbuffered || (Flags & SMB2_WRITEFLAG_WRITE_THROUGH) != 0)
157 			rc = EINVAL;
158 		else
159 			rc = smb_opipe_write(sr, &vdb->vdb_uio);
160 		if (rc == 0)
161 			XferCount = Length;
162 		break;
163 
164 	default:
165 		rc = EACCES;
166 		break;
167 	}
168 	status = smb_errno2status(rc);
169 
170 errout:
171 	sr->smb2_status = status;
172 	DTRACE_SMB2_DONE(op__Write, smb_request_t *, sr); /* arg.rw */
173 
174 	if (status) {
175 		smb2sr_put_error(sr, status);
176 		return (SDRC_SUCCESS);
177 	}
178 
179 	/*
180 	 * Encode SMB2 Write reply
181 	 */
182 	DataOff = SMB2_HDR_SIZE + 16;
183 	rc = smb_mbc_encodef(
184 	    &sr->reply, "wwlll",
185 	    17,	/* StructSize */	/* w */
186 	    0, /* reserved */		/* w */
187 	    XferCount,			/* l */
188 	    0, /* DataRemaining */	/* l */
189 	    0); /* Channel Info */	/* l */
190 	if (rc) {
191 		sr->smb2_status = NT_STATUS_INTERNAL_ERROR;
192 		return (SDRC_ERROR);
193 	}
194 
195 	mutex_enter(&of->f_mutex);
196 	of->f_seek_pos = Offset + XferCount;
197 	mutex_exit(&of->f_mutex);
198 
199 	return (SDRC_SUCCESS);
200 }
201