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1/*
2 * Cryptographic API.
3 *
4 * Deflate algorithm (RFC 1951), implemented here primarily for use
5 * by IPCOMP (RFC 3173 & RFC 2394).
6 *
7 * Copyright (c) 2003 James Morris <jmorris@intercode.com.au>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the Free
11 * Software Foundation; either version 2 of the License, or (at your option)
12 * any later version.
13 *
14 * FIXME: deflate transforms will require up to a total of about 436k of kernel
15 * memory on i386 (390k for compression, the rest for decompression), as the
16 * current zlib kernel code uses a worst case pre-allocation system by default.
17 * This needs to be fixed so that the amount of memory required is properly
18 * related to the winbits and memlevel parameters.
19 *
20 * The default winbits of 11 should suit most packets, and it may be something
21 * to configure on a per-tfm basis in the future.
22 *
23 * Currently, compression history is not maintained between tfm calls, as
24 * it is not needed for IPCOMP and keeps the code simpler. It can be
25 * implemented if someone wants it.
26 */
27#include <linux/init.h>
28#include <linux/module.h>
29#include <linux/crypto.h>
30#include <linux/zlib.h>
31#include <linux/vmalloc.h>
32#include <linux/interrupt.h>
33#include <linux/mm.h>
34#include <linux/net.h>
35
36#define DEFLATE_DEF_LEVEL Z_DEFAULT_COMPRESSION
37#define DEFLATE_DEF_WINBITS 11
38#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
39
40struct deflate_ctx {
41 struct z_stream_s comp_stream;
42 struct z_stream_s decomp_stream;
43};
44
45static int deflate_comp_init(struct deflate_ctx *ctx)
46{
47 int ret = 0;
48 struct z_stream_s *stream = &ctx->comp_stream;
49
50 stream->workspace = vzalloc(zlib_deflate_workspacesize(
51 -DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL));
52 if (!stream->workspace) {
53 ret = -ENOMEM;
54 goto out;
55 }
56 ret = zlib_deflateInit2(stream, DEFLATE_DEF_LEVEL, Z_DEFLATED,
57 -DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL,
58 Z_DEFAULT_STRATEGY);
59 if (ret != Z_OK) {
60 ret = -EINVAL;
61 goto out_free;
62 }
63out:
64 return ret;
65out_free:
66 vfree(stream->workspace);
67 goto out;
68}
69
70static int deflate_decomp_init(struct deflate_ctx *ctx)
71{
72 int ret = 0;
73 struct z_stream_s *stream = &ctx->decomp_stream;
74
75 stream->workspace = vzalloc(zlib_inflate_workspacesize());
76 if (!stream->workspace) {
77 ret = -ENOMEM;
78 goto out;
79 }
80 ret = zlib_inflateInit2(stream, -DEFLATE_DEF_WINBITS);
81 if (ret != Z_OK) {
82 ret = -EINVAL;
83 goto out_free;
84 }
85out:
86 return ret;
87out_free:
88 vfree(stream->workspace);
89 goto out;
90}
91
92static void deflate_comp_exit(struct deflate_ctx *ctx)
93{
94 zlib_deflateEnd(&ctx->comp_stream);
95 vfree(ctx->comp_stream.workspace);
96}
97
98static void deflate_decomp_exit(struct deflate_ctx *ctx)
99{
100 zlib_inflateEnd(&ctx->decomp_stream);
101 vfree(ctx->decomp_stream.workspace);
102}
103
104static int deflate_init(struct crypto_tfm *tfm)
105{
106 struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
107 int ret;
108
109 ret = deflate_comp_init(ctx);
110 if (ret)
111 goto out;
112 ret = deflate_decomp_init(ctx);
113 if (ret)
114 deflate_comp_exit(ctx);
115out:
116 return ret;
117}
118
119static void deflate_exit(struct crypto_tfm *tfm)
120{
121 struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
122
123 deflate_comp_exit(ctx);
124 deflate_decomp_exit(ctx);
125}
126
127static int deflate_compress(struct crypto_tfm *tfm, const u8 *src,
128 unsigned int slen, u8 *dst, unsigned int *dlen)
129{
130 int ret = 0;
131 struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
132 struct z_stream_s *stream = &dctx->comp_stream;
133
134 ret = zlib_deflateReset(stream);
135 if (ret != Z_OK) {
136 ret = -EINVAL;
137 goto out;
138 }
139
140 stream->next_in = (u8 *)src;
141 stream->avail_in = slen;
142 stream->next_out = (u8 *)dst;
143 stream->avail_out = *dlen;
144
145 ret = zlib_deflate(stream, Z_FINISH);
146 if (ret != Z_STREAM_END) {
147 ret = -EINVAL;
148 goto out;
149 }
150 ret = 0;
151 *dlen = stream->total_out;
152out:
153 return ret;
154}
155
156static int deflate_decompress(struct crypto_tfm *tfm, const u8 *src,
157 unsigned int slen, u8 *dst, unsigned int *dlen)
158{
159
160 int ret = 0;
161 struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
162 struct z_stream_s *stream = &dctx->decomp_stream;
163
164 ret = zlib_inflateReset(stream);
165 if (ret != Z_OK) {
166 ret = -EINVAL;
167 goto out;
168 }
169
170 stream->next_in = (u8 *)src;
171 stream->avail_in = slen;
172 stream->next_out = (u8 *)dst;
173 stream->avail_out = *dlen;
174
175 ret = zlib_inflate(stream, Z_SYNC_FLUSH);
176 /*
177 * Work around a bug in zlib, which sometimes wants to taste an extra
178 * byte when being used in the (undocumented) raw deflate mode.
179 * (From USAGI).
180 */
181 if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
182 u8 zerostuff = 0;
183 stream->next_in = &zerostuff;
184 stream->avail_in = 1;
185 ret = zlib_inflate(stream, Z_FINISH);
186 }
187 if (ret != Z_STREAM_END) {
188 ret = -EINVAL;
189 goto out;
190 }
191 ret = 0;
192 *dlen = stream->total_out;
193out:
194 return ret;
195}
196
197static struct crypto_alg alg = {
198 .cra_name = "deflate",
199 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
200 .cra_ctxsize = sizeof(struct deflate_ctx),
201 .cra_module = THIS_MODULE,
202 .cra_list = LIST_HEAD_INIT(alg.cra_list),
203 .cra_init = deflate_init,
204 .cra_exit = deflate_exit,
205 .cra_u = { .compress = {
206 .coa_compress = deflate_compress,
207 .coa_decompress = deflate_decompress } }
208};
209
210static int __init deflate_mod_init(void)
211{
212 return crypto_register_alg(&alg);
213}
214
215static void __exit deflate_mod_fini(void)
216{
217 crypto_unregister_alg(&alg);
218}
219
220module_init(deflate_mod_init);
221module_exit(deflate_mod_fini);
222
223MODULE_LICENSE("GPL");
224MODULE_DESCRIPTION("Deflate Compression Algorithm for IPCOMP");
225MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
226
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Cryptographic API.
4 *
5 * Deflate algorithm (RFC 1951), implemented here primarily for use
6 * by IPCOMP (RFC 3173 & RFC 2394).
7 *
8 * Copyright (c) 2003 James Morris <jmorris@intercode.com.au>
9 *
10 * FIXME: deflate transforms will require up to a total of about 436k of kernel
11 * memory on i386 (390k for compression, the rest for decompression), as the
12 * current zlib kernel code uses a worst case pre-allocation system by default.
13 * This needs to be fixed so that the amount of memory required is properly
14 * related to the winbits and memlevel parameters.
15 *
16 * The default winbits of 11 should suit most packets, and it may be something
17 * to configure on a per-tfm basis in the future.
18 *
19 * Currently, compression history is not maintained between tfm calls, as
20 * it is not needed for IPCOMP and keeps the code simpler. It can be
21 * implemented if someone wants it.
22 */
23#include <linux/init.h>
24#include <linux/module.h>
25#include <linux/crypto.h>
26#include <linux/zlib.h>
27#include <linux/vmalloc.h>
28#include <linux/interrupt.h>
29#include <linux/mm.h>
30#include <linux/net.h>
31#include <crypto/internal/scompress.h>
32
33#define DEFLATE_DEF_LEVEL Z_DEFAULT_COMPRESSION
34#define DEFLATE_DEF_WINBITS 11
35#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
36
37struct deflate_ctx {
38 struct z_stream_s comp_stream;
39 struct z_stream_s decomp_stream;
40};
41
42static int deflate_comp_init(struct deflate_ctx *ctx, int format)
43{
44 int ret = 0;
45 struct z_stream_s *stream = &ctx->comp_stream;
46
47 stream->workspace = vzalloc(zlib_deflate_workspacesize(
48 MAX_WBITS, MAX_MEM_LEVEL));
49 if (!stream->workspace) {
50 ret = -ENOMEM;
51 goto out;
52 }
53 if (format)
54 ret = zlib_deflateInit(stream, 3);
55 else
56 ret = zlib_deflateInit2(stream, DEFLATE_DEF_LEVEL, Z_DEFLATED,
57 -DEFLATE_DEF_WINBITS,
58 DEFLATE_DEF_MEMLEVEL,
59 Z_DEFAULT_STRATEGY);
60 if (ret != Z_OK) {
61 ret = -EINVAL;
62 goto out_free;
63 }
64out:
65 return ret;
66out_free:
67 vfree(stream->workspace);
68 goto out;
69}
70
71static int deflate_decomp_init(struct deflate_ctx *ctx, int format)
72{
73 int ret = 0;
74 struct z_stream_s *stream = &ctx->decomp_stream;
75
76 stream->workspace = vzalloc(zlib_inflate_workspacesize());
77 if (!stream->workspace) {
78 ret = -ENOMEM;
79 goto out;
80 }
81 if (format)
82 ret = zlib_inflateInit(stream);
83 else
84 ret = zlib_inflateInit2(stream, -DEFLATE_DEF_WINBITS);
85 if (ret != Z_OK) {
86 ret = -EINVAL;
87 goto out_free;
88 }
89out:
90 return ret;
91out_free:
92 vfree(stream->workspace);
93 goto out;
94}
95
96static void deflate_comp_exit(struct deflate_ctx *ctx)
97{
98 zlib_deflateEnd(&ctx->comp_stream);
99 vfree(ctx->comp_stream.workspace);
100}
101
102static void deflate_decomp_exit(struct deflate_ctx *ctx)
103{
104 zlib_inflateEnd(&ctx->decomp_stream);
105 vfree(ctx->decomp_stream.workspace);
106}
107
108static int __deflate_init(void *ctx, int format)
109{
110 int ret;
111
112 ret = deflate_comp_init(ctx, format);
113 if (ret)
114 goto out;
115 ret = deflate_decomp_init(ctx, format);
116 if (ret)
117 deflate_comp_exit(ctx);
118out:
119 return ret;
120}
121
122static void *gen_deflate_alloc_ctx(struct crypto_scomp *tfm, int format)
123{
124 struct deflate_ctx *ctx;
125 int ret;
126
127 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
128 if (!ctx)
129 return ERR_PTR(-ENOMEM);
130
131 ret = __deflate_init(ctx, format);
132 if (ret) {
133 kfree(ctx);
134 return ERR_PTR(ret);
135 }
136
137 return ctx;
138}
139
140static void *deflate_alloc_ctx(struct crypto_scomp *tfm)
141{
142 return gen_deflate_alloc_ctx(tfm, 0);
143}
144
145static void *zlib_deflate_alloc_ctx(struct crypto_scomp *tfm)
146{
147 return gen_deflate_alloc_ctx(tfm, 1);
148}
149
150static int deflate_init(struct crypto_tfm *tfm)
151{
152 struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
153
154 return __deflate_init(ctx, 0);
155}
156
157static void __deflate_exit(void *ctx)
158{
159 deflate_comp_exit(ctx);
160 deflate_decomp_exit(ctx);
161}
162
163static void deflate_free_ctx(struct crypto_scomp *tfm, void *ctx)
164{
165 __deflate_exit(ctx);
166 kfree_sensitive(ctx);
167}
168
169static void deflate_exit(struct crypto_tfm *tfm)
170{
171 struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
172
173 __deflate_exit(ctx);
174}
175
176static int __deflate_compress(const u8 *src, unsigned int slen,
177 u8 *dst, unsigned int *dlen, void *ctx)
178{
179 int ret = 0;
180 struct deflate_ctx *dctx = ctx;
181 struct z_stream_s *stream = &dctx->comp_stream;
182
183 ret = zlib_deflateReset(stream);
184 if (ret != Z_OK) {
185 ret = -EINVAL;
186 goto out;
187 }
188
189 stream->next_in = (u8 *)src;
190 stream->avail_in = slen;
191 stream->next_out = (u8 *)dst;
192 stream->avail_out = *dlen;
193
194 ret = zlib_deflate(stream, Z_FINISH);
195 if (ret != Z_STREAM_END) {
196 ret = -EINVAL;
197 goto out;
198 }
199 ret = 0;
200 *dlen = stream->total_out;
201out:
202 return ret;
203}
204
205static int deflate_compress(struct crypto_tfm *tfm, const u8 *src,
206 unsigned int slen, u8 *dst, unsigned int *dlen)
207{
208 struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
209
210 return __deflate_compress(src, slen, dst, dlen, dctx);
211}
212
213static int deflate_scompress(struct crypto_scomp *tfm, const u8 *src,
214 unsigned int slen, u8 *dst, unsigned int *dlen,
215 void *ctx)
216{
217 return __deflate_compress(src, slen, dst, dlen, ctx);
218}
219
220static int __deflate_decompress(const u8 *src, unsigned int slen,
221 u8 *dst, unsigned int *dlen, void *ctx)
222{
223
224 int ret = 0;
225 struct deflate_ctx *dctx = ctx;
226 struct z_stream_s *stream = &dctx->decomp_stream;
227
228 ret = zlib_inflateReset(stream);
229 if (ret != Z_OK) {
230 ret = -EINVAL;
231 goto out;
232 }
233
234 stream->next_in = (u8 *)src;
235 stream->avail_in = slen;
236 stream->next_out = (u8 *)dst;
237 stream->avail_out = *dlen;
238
239 ret = zlib_inflate(stream, Z_SYNC_FLUSH);
240 /*
241 * Work around a bug in zlib, which sometimes wants to taste an extra
242 * byte when being used in the (undocumented) raw deflate mode.
243 * (From USAGI).
244 */
245 if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
246 u8 zerostuff = 0;
247 stream->next_in = &zerostuff;
248 stream->avail_in = 1;
249 ret = zlib_inflate(stream, Z_FINISH);
250 }
251 if (ret != Z_STREAM_END) {
252 ret = -EINVAL;
253 goto out;
254 }
255 ret = 0;
256 *dlen = stream->total_out;
257out:
258 return ret;
259}
260
261static int deflate_decompress(struct crypto_tfm *tfm, const u8 *src,
262 unsigned int slen, u8 *dst, unsigned int *dlen)
263{
264 struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
265
266 return __deflate_decompress(src, slen, dst, dlen, dctx);
267}
268
269static int deflate_sdecompress(struct crypto_scomp *tfm, const u8 *src,
270 unsigned int slen, u8 *dst, unsigned int *dlen,
271 void *ctx)
272{
273 return __deflate_decompress(src, slen, dst, dlen, ctx);
274}
275
276static struct crypto_alg alg = {
277 .cra_name = "deflate",
278 .cra_driver_name = "deflate-generic",
279 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
280 .cra_ctxsize = sizeof(struct deflate_ctx),
281 .cra_module = THIS_MODULE,
282 .cra_init = deflate_init,
283 .cra_exit = deflate_exit,
284 .cra_u = { .compress = {
285 .coa_compress = deflate_compress,
286 .coa_decompress = deflate_decompress } }
287};
288
289static struct scomp_alg scomp[] = { {
290 .alloc_ctx = deflate_alloc_ctx,
291 .free_ctx = deflate_free_ctx,
292 .compress = deflate_scompress,
293 .decompress = deflate_sdecompress,
294 .base = {
295 .cra_name = "deflate",
296 .cra_driver_name = "deflate-scomp",
297 .cra_module = THIS_MODULE,
298 }
299}, {
300 .alloc_ctx = zlib_deflate_alloc_ctx,
301 .free_ctx = deflate_free_ctx,
302 .compress = deflate_scompress,
303 .decompress = deflate_sdecompress,
304 .base = {
305 .cra_name = "zlib-deflate",
306 .cra_driver_name = "zlib-deflate-scomp",
307 .cra_module = THIS_MODULE,
308 }
309} };
310
311static int __init deflate_mod_init(void)
312{
313 int ret;
314
315 ret = crypto_register_alg(&alg);
316 if (ret)
317 return ret;
318
319 ret = crypto_register_scomps(scomp, ARRAY_SIZE(scomp));
320 if (ret) {
321 crypto_unregister_alg(&alg);
322 return ret;
323 }
324
325 return ret;
326}
327
328static void __exit deflate_mod_fini(void)
329{
330 crypto_unregister_alg(&alg);
331 crypto_unregister_scomps(scomp, ARRAY_SIZE(scomp));
332}
333
334subsys_initcall(deflate_mod_init);
335module_exit(deflate_mod_fini);
336
337MODULE_LICENSE("GPL");
338MODULE_DESCRIPTION("Deflate Compression Algorithm for IPCOMP");
339MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
340MODULE_ALIAS_CRYPTO("deflate");