1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /*
27 * NDR heap management. The heap is used for temporary storage by
28 * both the client and server side library routines. In order to
29 * support the different requirements of the various RPCs, the heap
30 * can grow dynamically if required. We start with a single block
31 * and perform sub-allocations from it. If an RPC requires more space
32 * we will continue to add it a block at a time. This means that we
33 * don't hog lots of memory on every call to support the few times
34 * that we actually need a lot heap space.
35 *
36 * Note that there is no individual free function. Once space has been
37 * allocated, it remains allocated until the heap is destroyed. This
38 * shouldn't be an issue because the heap is being filled with data to
39 * be marshalled or unmarshalled and we need it all to be there until
40 * the point that the entire heap is no longer required.
41 */
42
43 #include <sys/errno.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <strings.h>
47 #include <sys/uio.h>
48
49 #include <smbsrv/libsmb.h>
50 #include <smbsrv/libmlrpc.h>
51 #include <smbsrv/smb_sid.h>
52
53 /*
54 * Allocate a heap structure and the first heap block. For many RPC
55 * operations this will be the only time we need to malloc memory
56 * in this instance of the heap. The only point of note here is that
57 * we put the heap management data in the first block to avoid a
58 * second malloc. Make sure that sizeof(ndr_heap_t) is smaller
59 * than NDR_HEAP_BLKSZ.
60 *
61 * Note that the heap management data is at the start of the first block.
62 *
63 * Returns a pointer to the newly created heap, which is used like an
64 * opaque handle with the rest of the heap management interface..
65 */
66 ndr_heap_t *
67 ndr_heap_create(void)
68 {
69 ndr_heap_t *heap;
70 char *base;
71 size_t allocsize = sizeof (ndr_heap_t) + NDR_HEAP_BLKSZ;
72
73 if ((heap = malloc(allocsize)) == NULL)
74 return (NULL);
75
76 base = (char *)heap;
77 bzero(heap, sizeof (ndr_heap_t));
78
79 heap->iovcnt = NDR_HEAP_MAXIOV;
80 heap->iov = heap->iovec;
81 heap->iov->iov_base = base;
82 heap->iov->iov_len = sizeof (ndr_heap_t);
83 heap->top = base + allocsize;
84 heap->next = base + sizeof (ndr_heap_t);
85
86 return (heap);
87 }
88
89 /*
90 * Deallocate all of the memory associated with a heap. This is the
91 * only way to deallocate heap memory, it isn't possible to free the
92 * space obtained by individual malloc calls.
93 *
94 * Note that the first block contains the heap management data, which
95 * is deleted last.
96 */
97 void
98 ndr_heap_destroy(ndr_heap_t *heap)
99 {
100 int i;
101 char *p;
102
103 if (heap) {
104 for (i = 1; i < NDR_HEAP_MAXIOV; ++i) {
105 if ((p = heap->iovec[i].iov_base) != NULL)
106 free(p);
107 }
108
109 free(heap);
110 }
111 }
112
113 /*
114 * Allocate space in the specified heap. All requests are padded, if
115 * required, to ensure dword alignment. If the current iov will be
116 * exceeded, we allocate a new block and setup the next iov. Otherwise
117 * all we have to do is move the next pointer and update the current
118 * iov length.
119 *
120 * On success, a pointer to the allocated (dword aligned) area is
121 * returned. Otherwise a null pointer is returned.
122 */
123 void *
124 ndr_heap_malloc(ndr_heap_t *heap, unsigned size)
125 {
126 char *p;
127 int incr_size;
128
129 size += NDR_ALIGN4(size);
130
131 if (heap == NULL || size == 0)
132 return (NULL);
133
134 p = heap->next;
135
136 if (p + size > heap->top) {
137 if ((heap->iovcnt == 0) || ((--heap->iovcnt) == 0))
138 return (NULL);
139
140 incr_size = (size < NDR_HEAP_BLKSZ) ? NDR_HEAP_BLKSZ : size;
141
142 if ((p = (char *)malloc(incr_size)) == NULL)
143 return (NULL);
144
145 ++heap->iov;
146 heap->iov->iov_base = p;
147 heap->iov->iov_len = 0;
148 heap->top = p + incr_size;
149 }
150
151 heap->next = p + size;
152 heap->iov->iov_len += size;
153 return ((void *)p);
154 }
155
156 /*
157 * Convenience function to do heap strdup.
158 */
159 void *
160 ndr_heap_strdup(ndr_heap_t *heap, const char *s)
161 {
162 int len;
163 void *p;
164
165 if (s == NULL)
166 return (NULL);
167
168 /*
169 * We don't need to clutter the heap with empty strings.
170 */
171 if ((len = strlen(s)) == 0)
172 return ("");
173
174 if ((p = ndr_heap_malloc(heap, len+1)) != NULL)
175 (void) strcpy((char *)p, s);
176
177 return (p);
178 }
179
180 /*
181 * Make an ndr_mstring_t from a regular string.
182 */
183 int
184 ndr_heap_mstring(ndr_heap_t *heap, const char *s, ndr_mstring_t *out)
185 {
186 if (s == NULL || out == NULL)
187 return (-1);
188
189 out->length = smb_wcequiv_strlen(s);
190 out->allosize = out->length + sizeof (smb_wchar_t);
191
192 if ((out->str = ndr_heap_strdup(heap, s)) == NULL)
193 return (-1);
194
195 return (0);
196 }
197
198 /*
199 * Our regular string marshalling always creates null terminated strings
200 * but some Windows clients and servers are pedantic about the string
201 * formats they will accept and require non-null terminated strings.
202 * This function can be used to build a wide-char, non-null terminated
203 * string in the heap as a varying/conformant array. We need to do the
204 * wide-char conversion here because the marshalling code won't be
205 * aware that this is really a string.
206 */
207 void
208 ndr_heap_mkvcs(ndr_heap_t *heap, char *s, ndr_vcstr_t *vc)
209 {
210 int mlen;
211
212 vc->wclen = smb_wcequiv_strlen(s);
213 vc->wcsize = vc->wclen;
214
215 mlen = sizeof (ndr_vcs_t) + vc->wcsize + sizeof (smb_wchar_t);
216
217 vc->vcs = ndr_heap_malloc(heap, mlen);
218
219 if (vc->vcs) {
220 vc->vcs->vc_first_is = 0;
221 vc->vcs->vc_length_is = vc->wclen / sizeof (smb_wchar_t);
222 (void) smb_mbstowcs((smb_wchar_t *)vc->vcs->buffer, s,
223 vc->vcs->vc_length_is);
224 }
225 }
226
227 void
228 ndr_heap_mkvcb(ndr_heap_t *heap, uint8_t *data, uint32_t datalen,
229 ndr_vcbuf_t *vcbuf)
230 {
231 int mlen;
232
233 if (data == NULL || datalen == 0) {
234 bzero(vcbuf, sizeof (ndr_vcbuf_t));
235 return;
236 }
237
238 vcbuf->len = datalen;
239 vcbuf->size = datalen;
240
241 mlen = sizeof (ndr_vcbuf_t) + datalen;
242
243 vcbuf->vcb = ndr_heap_malloc(heap, mlen);
244
245 if (vcbuf->vcb) {
246 vcbuf->vcb->vc_first_is = 0;
247 vcbuf->vcb->vc_length_is = datalen;
248 bcopy(data, vcbuf->vcb->buffer, datalen);
249 }
250 }
251
252 /*
253 * Duplcate a SID in the heap.
254 */
255 smb_sid_t *
256 ndr_heap_siddup(ndr_heap_t *heap, smb_sid_t *sid)
257 {
258 smb_sid_t *new_sid;
259 unsigned size;
260
261 if (sid == NULL)
262 return (NULL);
263
264 size = smb_sid_len(sid);
265
266 if ((new_sid = ndr_heap_malloc(heap, size)) == NULL)
267 return (NULL);
268
269 bcopy(sid, new_sid, size);
270 return (new_sid);
271 }
272
273 int
274 ndr_heap_used(ndr_heap_t *heap)
275 {
276 int used = 0;
277 int i;
278
279 for (i = 0; i < NDR_HEAP_MAXIOV; ++i)
280 used += heap->iovec[i].iov_len;
281
282 return (used);
283 }
284
285 int
286 ndr_heap_avail(ndr_heap_t *heap)
287 {
288 int avail;
289 int count;
290
291 count = (heap->iovcnt == 0) ? 0 : (heap->iovcnt - 1);
292
293 avail = count * NDR_HEAP_BLKSZ;
294 avail += (heap->top - heap->next);
295
296 return (avail);
297 }