source: branches/samba-3.5.x/libcli/smb/smb2_create_blob.c

Last change on this file was 414, checked in by Herwig Bauernfeind, 15 years ago

Samba 3.5.0: Initial import
File size: 5.2 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3
4 SMB2 Create Context Blob handling
5
6 Copyright (C) Andrew Tridgell 2005
7 Copyright (C) Stefan Metzmacher 2008-2009
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>.
21*/
22
23#include "includes.h"
24#include "../libcli/smb/smb_common.h"
25
26static size_t smb2_create_blob_padding(uint32_t offset, size_t n)
27{
28 if ((offset & (n-1)) == 0) return 0;
29 return n - (offset & (n-1));
30}
31
32/*
33 parse a set of SMB2 create blobs
34*/
35NTSTATUS smb2_create_blob_parse(TALLOC_CTX *mem_ctx, const DATA_BLOB buffer,
36 struct smb2_create_blobs *blobs)
37{
38 const uint8_t *data = buffer.data;
39 uint32_t remaining = buffer.length;
40
41 while (remaining > 0) {
42 uint32_t next;
43 uint32_t name_offset, name_length;
44 uint32_t reserved, data_offset;
45 uint32_t data_length;
46 char *tag;
47 DATA_BLOB b;
48 NTSTATUS status;
49
50 if (remaining < 16) {
51 return NT_STATUS_INVALID_PARAMETER;
52 }
53 next = IVAL(data, 0);
54 name_offset = SVAL(data, 4);
55 name_length = SVAL(data, 6);
56 reserved = SVAL(data, 8);
57 data_offset = SVAL(data, 10);
58 data_length = IVAL(data, 12);
59
60 if ((next & 0x7) != 0 ||
61 next > remaining ||
62 name_offset < 16 ||
63 name_offset > remaining ||
64 name_length != 4 || /* windows enforces this */
65 name_offset + name_length > remaining ||
66 data_offset < name_offset + name_length ||
67 data_offset > remaining ||
68 data_offset + (uint64_t)data_length > remaining) {
69 return NT_STATUS_INVALID_PARAMETER;
70 }
71
72 tag = talloc_strndup(mem_ctx, (const char *)data + name_offset, name_length);
73 if (tag == NULL) {
74 return NT_STATUS_NO_MEMORY;
75 }
76
77 b = data_blob_const(data+data_offset, data_length);
78 status = smb2_create_blob_add(mem_ctx, blobs, tag, b);
79 if (!NT_STATUS_IS_OK(status)) {
80 return status;
81 }
82
83 talloc_free(tag);
84
85 if (next == 0) break;
86
87 remaining -= next;
88 data += next;
89
90 if (remaining < 16) {
91 return NT_STATUS_INVALID_PARAMETER;
92 }
93 }
94
95 return NT_STATUS_OK;
96}
97
98
99/*
100 add a blob to a smb2_create attribute blob
101*/
102static NTSTATUS smb2_create_blob_push_one(TALLOC_CTX *mem_ctx, DATA_BLOB *buffer,
103 const struct smb2_create_blob *blob,
104 bool last)
105{
106 uint32_t ofs = buffer->length;
107 size_t tag_length = strlen(blob->tag);
108 uint8_t pad = smb2_create_blob_padding(blob->data.length+tag_length, 4);
109
110 if (!data_blob_realloc(mem_ctx, buffer,
111 buffer->length + 0x14 + tag_length + blob->data.length + pad))
112 return NT_STATUS_NO_MEMORY;
113
114 if (last) {
115 SIVAL(buffer->data, ofs+0x00, 0);
116 } else {
117 SIVAL(buffer->data, ofs+0x00, 0x14 + tag_length + blob->data.length + pad);
118 }
119 SSVAL(buffer->data, ofs+0x04, 0x10); /* offset of tag */
120 SIVAL(buffer->data, ofs+0x06, tag_length); /* tag length */
121 SSVAL(buffer->data, ofs+0x0A, 0x14 + tag_length); /* offset of data */
122 SIVAL(buffer->data, ofs+0x0C, blob->data.length);
123 memcpy(buffer->data+ofs+0x10, blob->tag, tag_length);
124 SIVAL(buffer->data, ofs+0x10+tag_length, 0); /* pad? */
125 memcpy(buffer->data+ofs+0x14+tag_length, blob->data.data, blob->data.length);
126 memset(buffer->data+ofs+0x14+tag_length+blob->data.length, 0, pad);
127
128 return NT_STATUS_OK;
129}
130
131
132/*
133 create a buffer of a set of create blobs
134*/
135NTSTATUS smb2_create_blob_push(TALLOC_CTX *mem_ctx, DATA_BLOB *buffer,
136 const struct smb2_create_blobs blobs)
137{
138 int i;
139 NTSTATUS status;
140
141 *buffer = data_blob(NULL, 0);
142 for (i=0; i < blobs.num_blobs; i++) {
143 bool last = false;
144 const struct smb2_create_blob *c;
145
146 if ((i + 1) == blobs.num_blobs) {
147 last = true;
148 }
149
150 c = &blobs.blobs[i];
151 status = smb2_create_blob_push_one(mem_ctx, buffer, c, last);
152 if (!NT_STATUS_IS_OK(status)) {
153 return status;
154 }
155 }
156 return NT_STATUS_OK;
157}
158
159
160NTSTATUS smb2_create_blob_add(TALLOC_CTX *mem_ctx, struct smb2_create_blobs *b,
161 const char *tag, DATA_BLOB data)
162{
163 struct smb2_create_blob *array;
164
165 array = talloc_realloc(mem_ctx, b->blobs,
166 struct smb2_create_blob,
167 b->num_blobs + 1);
168 NT_STATUS_HAVE_NO_MEMORY(array);
169 b->blobs = array;
170
171 b->blobs[b->num_blobs].tag = talloc_strdup(b->blobs, tag);
172 NT_STATUS_HAVE_NO_MEMORY(b->blobs[b->num_blobs].tag);
173
174 if (data.data) {
175 b->blobs[b->num_blobs].data = data_blob_talloc(b->blobs,
176 data.data,
177 data.length);
178 NT_STATUS_HAVE_NO_MEMORY(b->blobs[b->num_blobs].data.data);
179 } else {
180 b->blobs[b->num_blobs].data = data_blob(NULL, 0);
181 }
182
183 b->num_blobs += 1;
184
185 return NT_STATUS_OK;
186}
187
188/*
189 * return the first blob with the given tag
190 */
191struct smb2_create_blob *smb2_create_blob_find(const struct smb2_create_blobs *b,
192 const char *tag)
193{
194 uint32_t i;
195
196 for (i=0; i < b->num_blobs; i++) {
197 if (strcmp(b->blobs[i].tag, tag) == 0) {
198 return &b->blobs[i];
199 }
200 }
201
202 return NULL;
203}
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