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Viewing changes to librpc/ndr/ndr_compression.c

  • Committer: Chuck Short
  • Date: 2010-09-28 20:38:39 UTC
  • Revision ID: zulcss@ubuntu.com-20100928203839-pgjulytsi9ue63x1
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librpc/ndr/ndr_compression.c
 
1
/* 
 
2
   Unix SMB/CIFS implementation.
 
3
 
 
4
   libndr compression support
 
5
 
 
6
   Copyright (C) Stefan Metzmacher 2005
 
7
   Copyright (C) Matthieu Suiche 2008
 
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 "../lib/compression/lzxpress.h"
 
25
#include "librpc/ndr/libndr.h"
 
26
#include "../librpc/ndr/ndr_compression.h"
 
27
#include <zlib.h>
 
28
 
 
29
static voidpf ndr_zlib_alloc(voidpf opaque, uInt items, uInt size)
 
30
{
 
31
        return talloc_zero_size(opaque, items * size);
 
32
}
 
33
 
 
34
static void  ndr_zlib_free(voidpf opaque, voidpf address)
 
35
{
 
36
        talloc_free(address);
 
37
}
 
38
 
 
39
static enum ndr_err_code ndr_pull_compression_mszip_chunk(struct ndr_pull *ndrpull,
 
40
                                                 struct ndr_push *ndrpush,
 
41
                                                 z_stream *z,
 
42
                                                 bool *last)
 
43
{
 
44
        DATA_BLOB comp_chunk;
 
45
        uint32_t comp_chunk_offset;
 
46
        uint32_t comp_chunk_size;
 
47
        DATA_BLOB plain_chunk;
 
48
        uint32_t plain_chunk_offset;
 
49
        uint32_t plain_chunk_size;
 
50
        int z_ret;
 
51
 
 
52
        NDR_CHECK(ndr_pull_uint32(ndrpull, NDR_SCALARS, &plain_chunk_size));
 
53
        if (plain_chunk_size > 0x00008000) {
 
54
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION, "Bad MSZIP plain chunk size %08X > 0x00008000 (PULL)", 
 
55
                                      plain_chunk_size);
 
56
        }
 
57
 
 
58
        NDR_CHECK(ndr_pull_uint32(ndrpull, NDR_SCALARS, &comp_chunk_size));
 
59
 
 
60
        DEBUG(9,("MSZIP plain_chunk_size: %08X (%u) comp_chunk_size: %08X (%u)\n",
 
61
                 plain_chunk_size, plain_chunk_size, comp_chunk_size, comp_chunk_size));
 
62
 
 
63
        comp_chunk_offset = ndrpull->offset;
 
64
        NDR_CHECK(ndr_pull_advance(ndrpull, comp_chunk_size));
 
65
        comp_chunk.length = comp_chunk_size;
 
66
        comp_chunk.data = ndrpull->data + comp_chunk_offset;
 
67
 
 
68
        plain_chunk_offset = ndrpush->offset;
 
69
        NDR_CHECK(ndr_push_zero(ndrpush, plain_chunk_size));
 
70
        plain_chunk.length = plain_chunk_size;
 
71
        plain_chunk.data = ndrpush->data + plain_chunk_offset;
 
72
 
 
73
        if (comp_chunk.length < 2) {
 
74
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
75
                                      "Bad MSZIP comp chunk size %u < 2 (PULL)",
 
76
                                      (unsigned int)comp_chunk.length);
 
77
        }
 
78
        /* CK = Chris Kirmse, official Microsoft purloiner */
 
79
        if (comp_chunk.data[0] != 'C' ||
 
80
            comp_chunk.data[1] != 'K') {
 
81
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
82
                                      "Bad MSZIP invalid prefix [%c%c] != [CK]",
 
83
                                      comp_chunk.data[0], comp_chunk.data[1]);
 
84
        }
 
85
 
 
86
        z->next_in      = comp_chunk.data + 2;
 
87
        z->avail_in     = comp_chunk.length -2;
 
88
        z->total_in     = 0;
 
89
 
 
90
        z->next_out     = plain_chunk.data;
 
91
        z->avail_out    = plain_chunk.length;
 
92
        z->total_out    = 0;
 
93
 
 
94
        if (!z->opaque) {
 
95
                /* the first time we need to intialize completely */
 
96
                z->zalloc       = ndr_zlib_alloc;
 
97
                z->zfree        = ndr_zlib_free;
 
98
                z->opaque       = ndrpull;
 
99
 
 
100
                z_ret = inflateInit2(z, -15);
 
101
                if (z_ret != Z_OK) {
 
102
                        return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
103
                                              "Bad inflateInit2 error %s(%d) (PULL)",
 
104
                                              zError(z_ret), z_ret);
 
105
 
 
106
                }
 
107
        }
 
108
 
 
109
        /* call inflate untill we get Z_STREAM_END or an error */
 
110
        while (true) {
 
111
                z_ret = inflate(z, Z_BLOCK);
 
112
                if (z_ret != Z_OK) break;
 
113
        }
 
114
 
 
115
        if (z_ret != Z_STREAM_END) {
 
116
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
117
                                      "Bad inflate(Z_BLOCK) error %s(%d) (PULL)",
 
118
                                      zError(z_ret), z_ret);
 
119
        }
 
120
 
 
121
        if (z->avail_in) {
 
122
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
123
                                      "MSZIP not all avail_in[%u] bytes consumed (PULL)",
 
124
                                      z->avail_in);
 
125
        }
 
126
 
 
127
        if (z->avail_out) {
 
128
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
129
                                      "MSZIP not all avail_out[%u] bytes consumed (PULL)",
 
130
                                      z->avail_out);
 
131
        }
 
132
 
 
133
        if ((plain_chunk_size < 0x00008000) || (ndrpull->offset+4 >= ndrpull->data_size)) {
 
134
                /* this is the last chunk */
 
135
                *last = true;
 
136
        }
 
137
 
 
138
        z_ret = inflateReset(z);
 
139
        if (z_ret != Z_OK) {
 
140
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
141
                                      "Bad inflateReset error %s(%d) (PULL)",
 
142
                                      zError(z_ret), z_ret);
 
143
        }
 
144
 
 
145
        z_ret = inflateSetDictionary(z, plain_chunk.data, plain_chunk.length);
 
146
        if (z_ret != Z_OK) {
 
147
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
148
                                      "Bad inflateSetDictionary error %s(%d) (PULL)",
 
149
                                      zError(z_ret), z_ret);
 
150
        }
 
151
 
 
152
        return NDR_ERR_SUCCESS;
 
153
}
 
154
 
 
155
static enum ndr_err_code ndr_push_compression_mszip_chunk(struct ndr_push *ndrpush,
 
156
                                                          struct ndr_pull *ndrpull,
 
157
                                                          z_stream *z,
 
158
                                                          bool *last)
 
159
{
 
160
        DATA_BLOB comp_chunk;
 
161
        uint32_t comp_chunk_size;
 
162
        uint32_t comp_chunk_size_offset;
 
163
        DATA_BLOB plain_chunk;
 
164
        uint32_t plain_chunk_size;
 
165
        uint32_t plain_chunk_offset;
 
166
        uint32_t max_plain_size = 0x00008000;
 
167
        uint32_t max_comp_size = 0x00008000 + 2 + 12 /*TODO: what value do we really need here?*/;
 
168
        uint32_t tmp_offset;
 
169
        int z_ret;
 
170
 
 
171
        plain_chunk_size = MIN(max_plain_size, ndrpull->data_size - ndrpull->offset);
 
172
        plain_chunk_offset = ndrpull->offset;
 
173
        NDR_CHECK(ndr_pull_advance(ndrpull, plain_chunk_size));
 
174
 
 
175
        plain_chunk.data = ndrpull->data + plain_chunk_offset;
 
176
        plain_chunk.length = plain_chunk_size;
 
177
 
 
178
        if (plain_chunk_size < max_plain_size) {
 
179
                *last = true;
 
180
        }
 
181
 
 
182
        NDR_CHECK(ndr_push_uint32(ndrpush, NDR_SCALARS, plain_chunk_size));
 
183
        comp_chunk_size_offset = ndrpush->offset;
 
184
        NDR_CHECK(ndr_push_uint32(ndrpush, NDR_SCALARS, 0xFEFEFEFE));
 
185
 
 
186
        NDR_CHECK(ndr_push_expand(ndrpush, max_comp_size));
 
187
 
 
188
        comp_chunk.data = ndrpush->data + ndrpush->offset;
 
189
        comp_chunk.length = max_comp_size;
 
190
 
 
191
        /* CK = Chris Kirmse, official Microsoft purloiner */
 
192
        comp_chunk.data[0] = 'C';
 
193
        comp_chunk.data[1] = 'K';
 
194
 
 
195
        z->next_in      = plain_chunk.data;
 
196
        z->avail_in     = plain_chunk.length;
 
197
        z->total_in     = 0;
 
198
 
 
199
        z->next_out     = comp_chunk.data + 2;
 
200
        z->avail_out    = comp_chunk.length - 2;
 
201
        z->total_out    = 0;
 
202
 
 
203
        if (!z->opaque) {
 
204
                /* the first time we need to intialize completely */
 
205
                z->zalloc       = ndr_zlib_alloc;
 
206
                z->zfree        = ndr_zlib_free;
 
207
                z->opaque       = ndrpull;
 
208
 
 
209
                /* TODO: find how to trigger the same parameters windows uses */
 
210
                z_ret = deflateInit2(z,
 
211
                                     Z_DEFAULT_COMPRESSION,
 
212
                                     Z_DEFLATED,
 
213
                                     -15,
 
214
                                     9,
 
215
                                     Z_DEFAULT_STRATEGY);
 
216
                if (z_ret != Z_OK) {
 
217
                        return ndr_push_error(ndrpush, NDR_ERR_COMPRESSION,
 
218
                                              "Bad deflateInit2 error %s(%d) (PUSH)",
 
219
                                              zError(z_ret), z_ret);
 
220
 
 
221
                }
 
222
        }
 
223
 
 
224
        /* call deflate untill we get Z_STREAM_END or an error */
 
225
        while (true) {
 
226
                z_ret = deflate(z, Z_FINISH);
 
227
                if (z_ret != Z_OK) break;
 
228
        }
 
229
        if (z_ret != Z_STREAM_END) {
 
230
                return ndr_push_error(ndrpush, NDR_ERR_COMPRESSION,
 
231
                                      "Bad delate(Z_BLOCK) error %s(%d) (PUSH)",
 
232
                                      zError(z_ret), z_ret);
 
233
        }
 
234
 
 
235
        if (z->avail_in) {
 
236
                return ndr_push_error(ndrpush, NDR_ERR_COMPRESSION,
 
237
                                      "MSZIP not all avail_in[%u] bytes consumed (PUSH)",
 
238
                                      z->avail_in);
 
239
        }
 
240
 
 
241
        comp_chunk_size = 2 + z->total_out;
 
242
 
 
243
        z_ret = deflateReset(z);
 
244
        if (z_ret != Z_OK) {
 
245
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
246
                                      "Bad deflateReset error %s(%d) (PULL)",
 
247
                                      zError(z_ret), z_ret);
 
248
        }
 
249
 
 
250
        z_ret = deflateSetDictionary(z, plain_chunk.data, plain_chunk.length);
 
251
        if (z_ret != Z_OK) {
 
252
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
253
                                      "Bad deflateSetDictionary error %s(%d) (PULL)",
 
254
                                      zError(z_ret), z_ret);
 
255
        }
 
256
 
 
257
        tmp_offset = ndrpush->offset;
 
258
        ndrpush->offset = comp_chunk_size_offset;
 
259
        NDR_CHECK(ndr_push_uint32(ndrpush, NDR_SCALARS, comp_chunk_size));
 
260
        ndrpush->offset = tmp_offset;
 
261
 
 
262
        DEBUG(9,("MSZIP comp plain_chunk_size: %08X (%u) comp_chunk_size: %08X (%u)\n",
 
263
                 (unsigned int)plain_chunk.length,
 
264
                 (unsigned int)plain_chunk.length,
 
265
                 comp_chunk_size, comp_chunk_size));
 
266
 
 
267
        ndrpush->offset += comp_chunk_size;
 
268
        return NDR_ERR_SUCCESS;
 
269
}
 
270
 
 
271
static enum ndr_err_code ndr_pull_compression_xpress_chunk(struct ndr_pull *ndrpull,
 
272
                                                  struct ndr_push *ndrpush,
 
273
                                                  bool *last)
 
274
{
 
275
        DATA_BLOB comp_chunk;
 
276
        DATA_BLOB plain_chunk;
 
277
        uint32_t comp_chunk_offset;
 
278
        uint32_t plain_chunk_offset;
 
279
        uint32_t comp_chunk_size;
 
280
        uint32_t plain_chunk_size;
 
281
        ssize_t ret;
 
282
 
 
283
        NDR_CHECK(ndr_pull_uint32(ndrpull, NDR_SCALARS, &plain_chunk_size));
 
284
        if (plain_chunk_size > 0x00010000) {
 
285
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION, "Bad XPRESS plain chunk size %08X > 0x00010000 (PULL)", 
 
286
                                      plain_chunk_size);
 
287
        }
 
288
 
 
289
        NDR_CHECK(ndr_pull_uint32(ndrpull, NDR_SCALARS, &comp_chunk_size));
 
290
 
 
291
        comp_chunk_offset = ndrpull->offset;
 
292
        NDR_CHECK(ndr_pull_advance(ndrpull, comp_chunk_size));
 
293
        comp_chunk.length = comp_chunk_size;
 
294
        comp_chunk.data = ndrpull->data + comp_chunk_offset;
 
295
 
 
296
        plain_chunk_offset = ndrpush->offset;
 
297
        NDR_CHECK(ndr_push_zero(ndrpush, plain_chunk_size));
 
298
        plain_chunk.length = plain_chunk_size;
 
299
        plain_chunk.data = ndrpush->data + plain_chunk_offset;
 
300
 
 
301
        DEBUG(9,("XPRESS plain_chunk_size: %08X (%u) comp_chunk_size: %08X (%u)\n",
 
302
                 plain_chunk_size, plain_chunk_size, comp_chunk_size, comp_chunk_size));
 
303
 
 
304
        /* Uncompressing the buffer using LZ Xpress algorithm */
 
305
        ret = lzxpress_decompress(comp_chunk.data,
 
306
                                  comp_chunk.length,
 
307
                                  plain_chunk.data,
 
308
                                  plain_chunk.length);
 
309
        if (ret < 0) {
 
310
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
311
                                      "XPRESS lzxpress_decompress() returned %d\n",
 
312
                                      (int)ret);
 
313
        }
 
314
        plain_chunk.length = ret;
 
315
 
 
316
        if ((plain_chunk_size < 0x00010000) || (ndrpull->offset+4 >= ndrpull->data_size)) {
 
317
                /* this is the last chunk */
 
318
                *last = true;
 
319
        }
 
320
 
 
321
        return NDR_ERR_SUCCESS;
 
322
}
 
323
 
 
324
static enum ndr_err_code ndr_push_compression_xpress_chunk(struct ndr_push *ndrpush,
 
325
                                                           struct ndr_pull *ndrpull,
 
326
                                                           bool *last)
 
327
{
 
328
        DATA_BLOB comp_chunk;
 
329
        uint32_t comp_chunk_size_offset;
 
330
        DATA_BLOB plain_chunk;
 
331
        uint32_t plain_chunk_size;
 
332
        uint32_t plain_chunk_offset;
 
333
        uint32_t max_plain_size = 0x00010000;
 
334
        uint32_t max_comp_size = 0x00020000 + 2; /* TODO: use the correct value here */
 
335
        uint32_t tmp_offset;
 
336
        ssize_t ret;
 
337
 
 
338
        plain_chunk_size = MIN(max_plain_size, ndrpull->data_size - ndrpull->offset);
 
339
        plain_chunk_offset = ndrpull->offset;
 
340
        NDR_CHECK(ndr_pull_advance(ndrpull, plain_chunk_size));
 
341
 
 
342
        plain_chunk.data = ndrpull->data + plain_chunk_offset;
 
343
        plain_chunk.length = plain_chunk_size;
 
344
 
 
345
        if (plain_chunk_size < max_plain_size) {
 
346
                *last = true;
 
347
        }
 
348
 
 
349
        NDR_CHECK(ndr_push_uint32(ndrpush, NDR_SCALARS, plain_chunk_size));
 
350
        comp_chunk_size_offset = ndrpush->offset;
 
351
        NDR_CHECK(ndr_push_uint32(ndrpush, NDR_SCALARS, 0xFEFEFEFE));
 
352
 
 
353
        NDR_CHECK(ndr_push_expand(ndrpush, max_comp_size));
 
354
 
 
355
        comp_chunk.data = ndrpush->data + ndrpush->offset;
 
356
        comp_chunk.length = max_comp_size;
 
357
 
 
358
        /* Compressing the buffer using LZ Xpress algorithm */
 
359
        ret = lzxpress_compress(plain_chunk.data,
 
360
                                plain_chunk.length,
 
361
                                comp_chunk.data,
 
362
                                comp_chunk.length);
 
363
        if (ret < 0) {
 
364
                return ndr_pull_error(ndrpull, NDR_ERR_COMPRESSION,
 
365
                                      "XPRESS lzxpress_compress() returned %d\n",
 
366
                                      (int)ret);
 
367
        }
 
368
        comp_chunk.length = ret;
 
369
 
 
370
        tmp_offset = ndrpush->offset;
 
371
        ndrpush->offset = comp_chunk_size_offset;
 
372
        NDR_CHECK(ndr_push_uint32(ndrpush, NDR_SCALARS, comp_chunk.length));
 
373
        ndrpush->offset = tmp_offset;
 
374
 
 
375
        ndrpush->offset += comp_chunk.length;
 
376
        return NDR_ERR_SUCCESS;
 
377
}
 
378
 
 
379
/*
 
380
  handle compressed subcontext buffers, which in midl land are user-marshalled, but
 
381
  we use magic in pidl to make them easier to cope with
 
382
*/
 
383
enum ndr_err_code ndr_pull_compression_start(struct ndr_pull *subndr,
 
384
                                    struct ndr_pull **_comndr,
 
385
                                    enum ndr_compression_alg compression_alg,
 
386
                                    ssize_t decompressed_len)
 
387
{
 
388
        struct ndr_push *ndrpush;
 
389
        struct ndr_pull *comndr;
 
390
        DATA_BLOB uncompressed;
 
391
        bool last = false;
 
392
        z_stream z;
 
393
 
 
394
        ndrpush = ndr_push_init_ctx(subndr, subndr->iconv_convenience);
 
395
        NDR_ERR_HAVE_NO_MEMORY(ndrpush);
 
396
 
 
397
        switch (compression_alg) {
 
398
        case NDR_COMPRESSION_MSZIP:
 
399
                ZERO_STRUCT(z);
 
400
                while (!last) {
 
401
                        NDR_CHECK(ndr_pull_compression_mszip_chunk(subndr, ndrpush, &z, &last));
 
402
                }
 
403
                break;
 
404
 
 
405
        case NDR_COMPRESSION_XPRESS:
 
406
                while (!last) {
 
407
                        NDR_CHECK(ndr_pull_compression_xpress_chunk(subndr, ndrpush, &last));
 
408
                }
 
409
                break;
 
410
 
 
411
        default:
 
412
                return ndr_pull_error(subndr, NDR_ERR_COMPRESSION, "Bad compression algorithm %d (PULL)",
 
413
                                      compression_alg);
 
414
        }
 
415
 
 
416
        uncompressed = ndr_push_blob(ndrpush);
 
417
        if (uncompressed.length != decompressed_len) {
 
418
                return ndr_pull_error(subndr, NDR_ERR_COMPRESSION,
 
419
                                      "Bad uncompressed_len [%u] != [%u](0x%08X) (PULL)",
 
420
                                      (int)uncompressed.length,
 
421
                                      (int)decompressed_len,
 
422
                                      (int)decompressed_len);
 
423
        }
 
424
 
 
425
        comndr = talloc_zero(subndr, struct ndr_pull);
 
426
        NDR_ERR_HAVE_NO_MEMORY(comndr);
 
427
        comndr->flags           = subndr->flags;
 
428
        comndr->current_mem_ctx = subndr->current_mem_ctx;
 
429
 
 
430
        comndr->data            = uncompressed.data;
 
431
        comndr->data_size       = uncompressed.length;
 
432
        comndr->offset          = 0;
 
433
 
 
434
        comndr->iconv_convenience = talloc_reference(comndr, subndr->iconv_convenience);
 
435
 
 
436
        *_comndr = comndr;
 
437
        return NDR_ERR_SUCCESS;
 
438
}
 
439
 
 
440
enum ndr_err_code ndr_pull_compression_end(struct ndr_pull *subndr,
 
441
                                  struct ndr_pull *comndr,
 
442
                                  enum ndr_compression_alg compression_alg,
 
443
                                  ssize_t decompressed_len)
 
444
{
 
445
        return NDR_ERR_SUCCESS;
 
446
}
 
447
 
 
448
/*
 
449
  push a compressed subcontext
 
450
*/
 
451
enum ndr_err_code ndr_push_compression_start(struct ndr_push *subndr,
 
452
                                    struct ndr_push **_uncomndr,
 
453
                                    enum ndr_compression_alg compression_alg,
 
454
                                    ssize_t decompressed_len)
 
455
{
 
456
        struct ndr_push *uncomndr;
 
457
 
 
458
        switch (compression_alg) {
 
459
        case NDR_COMPRESSION_MSZIP:
 
460
        case NDR_COMPRESSION_XPRESS:
 
461
                break;
 
462
        default:
 
463
                return ndr_push_error(subndr, NDR_ERR_COMPRESSION,
 
464
                                      "Bad compression algorithm %d (PUSH)",
 
465
                                      compression_alg);
 
466
        }
 
467
 
 
468
        uncomndr = ndr_push_init_ctx(subndr, subndr->iconv_convenience);
 
469
        NDR_ERR_HAVE_NO_MEMORY(uncomndr);
 
470
        uncomndr->flags = subndr->flags;
 
471
 
 
472
        *_uncomndr = uncomndr;
 
473
        return NDR_ERR_SUCCESS;
 
474
}
 
475
 
 
476
/*
 
477
  push a compressed subcontext
 
478
*/
 
479
enum ndr_err_code ndr_push_compression_end(struct ndr_push *subndr,
 
480
                                  struct ndr_push *uncomndr,
 
481
                                  enum ndr_compression_alg compression_alg,
 
482
                                  ssize_t decompressed_len)
 
483
{
 
484
        struct ndr_pull *ndrpull;
 
485
        bool last = false;
 
486
        z_stream z;
 
487
 
 
488
        ndrpull = talloc_zero(uncomndr, struct ndr_pull);
 
489
        NDR_ERR_HAVE_NO_MEMORY(ndrpull);
 
490
        ndrpull->flags          = uncomndr->flags;
 
491
        ndrpull->data           = uncomndr->data;
 
492
        ndrpull->data_size      = uncomndr->offset;
 
493
        ndrpull->offset         = 0;
 
494
 
 
495
        ndrpull->iconv_convenience = talloc_reference(ndrpull, subndr->iconv_convenience);
 
496
 
 
497
        switch (compression_alg) {
 
498
        case NDR_COMPRESSION_MSZIP:
 
499
                ZERO_STRUCT(z);
 
500
                while (!last) {
 
501
                        NDR_CHECK(ndr_push_compression_mszip_chunk(subndr, ndrpull, &z, &last));
 
502
                }
 
503
                break;
 
504
 
 
505
        case NDR_COMPRESSION_XPRESS:
 
506
                while (!last) {
 
507
                        NDR_CHECK(ndr_push_compression_xpress_chunk(subndr, ndrpull, &last));
 
508
                }
 
509
                break;
 
510
 
 
511
        default:
 
512
                return ndr_push_error(subndr, NDR_ERR_COMPRESSION, "Bad compression algorithm %d (PUSH)", 
 
513
                                      compression_alg);
 
514
        }
 
515
 
 
516
        talloc_free(uncomndr);
 
517
        return NDR_ERR_SUCCESS;
 
518
}