[linux.git] / crypto / zlib.c

/*
 * Cryptographic API.
 *
 * Zlib algorithm
 *
 * Copyright 2008 Sony Corporation
 *
 * Based on deflate.c, which is
 * Copyright (c) 2003 James Morris <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * FIXME: deflate transforms will require up to a total of about 436k of kernel
 * memory on i386 (390k for compression, the rest for decompression), as the
 * current zlib kernel code uses a worst case pre-allocation system by default.
 * This needs to be fixed so that the amount of memory required is properly
 * related to the winbits and memlevel parameters.
 */

#define pr_fmt(fmt)	"%s: " fmt, __func__

#include <linux/init.h>
#include <linux/module.h>
#include <linux/zlib.h>
#include <linux/vmalloc.h>
#include <linux/interrupt.h>
#include <linux/mm.h>
#include <linux/net.h>
#include <linux/slab.h>

#include <crypto/internal/compress.h>

#include <net/netlink.h>


struct zlib_ctx {
	struct z_stream_s comp_stream;
	struct z_stream_s decomp_stream;
	int decomp_windowBits;
};


static void zlib_comp_exit(struct zlib_ctx *ctx)
{
	struct z_stream_s *stream = &ctx->comp_stream;

	if (stream->workspace) {
		zlib_deflateEnd(stream);
		vfree(stream->workspace);
		stream->workspace = NULL;
	}
}

static void zlib_decomp_exit(struct zlib_ctx *ctx)
{
	struct z_stream_s *stream = &ctx->decomp_stream;

	if (stream->workspace) {
		zlib_inflateEnd(stream);
		kfree(stream->workspace);
		stream->workspace = NULL;
	}
}

static int zlib_init(struct crypto_tfm *tfm)
{
	return 0;
}

static void zlib_exit(struct crypto_tfm *tfm)
{
	struct zlib_ctx *ctx = crypto_tfm_ctx(tfm);

	zlib_comp_exit(ctx);
	zlib_decomp_exit(ctx);
}


static int zlib_compress_setup(struct crypto_pcomp *tfm, void *params,
			       unsigned int len)
{
	struct zlib_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &ctx->comp_stream;
	struct nlattr *tb[ZLIB_COMP_MAX + 1];
	size_t workspacesize;
	int ret;

	ret = nla_parse(tb, ZLIB_COMP_MAX, params, len, NULL);
	if (ret)
		return ret;

	zlib_comp_exit(ctx);

	workspacesize = zlib_deflate_workspacesize();
	stream->workspace = vmalloc(workspacesize);
	if (!stream->workspace)
		return -ENOMEM;

	memset(stream->workspace, 0, workspacesize);
	ret = zlib_deflateInit2(stream,
				tb[ZLIB_COMP_LEVEL]
					? nla_get_u32(tb[ZLIB_COMP_LEVEL])
					: Z_DEFAULT_COMPRESSION,
				tb[ZLIB_COMP_METHOD]
					? nla_get_u32(tb[ZLIB_COMP_METHOD])
					: Z_DEFLATED,
				tb[ZLIB_COMP_WINDOWBITS]
					? nla_get_u32(tb[ZLIB_COMP_WINDOWBITS])
					: MAX_WBITS,
				tb[ZLIB_COMP_MEMLEVEL]
					? nla_get_u32(tb[ZLIB_COMP_MEMLEVEL])
					: DEF_MEM_LEVEL,
				tb[ZLIB_COMP_STRATEGY]
					? nla_get_u32(tb[ZLIB_COMP_STRATEGY])
					: Z_DEFAULT_STRATEGY);
	if (ret != Z_OK) {
		vfree(stream->workspace);
		stream->workspace = NULL;
		return -EINVAL;
	}

	return 0;
}

static int zlib_compress_init(struct crypto_pcomp *tfm)
{
	int ret;
	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &dctx->comp_stream;

	ret = zlib_deflateReset(stream);
	if (ret != Z_OK)
		return -EINVAL;

	return 0;
}

static int zlib_compress_update(struct crypto_pcomp *tfm,
				struct comp_request *req)
{
	int ret;
	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &dctx->comp_stream;

	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
	stream->next_in = req->next_in;
	stream->avail_in = req->avail_in;
	stream->next_out = req->next_out;
	stream->avail_out = req->avail_out;

	ret = zlib_deflate(stream, Z_NO_FLUSH);
	switch (ret) {
	case Z_OK:
		break;

	case Z_BUF_ERROR:
		pr_debug("zlib_deflate could not make progress\n");
		return -EAGAIN;

	default:
		pr_debug("zlib_deflate failed %d\n", ret);
		return -EINVAL;
	}

	ret = req->avail_out - stream->avail_out;
	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
		 stream->avail_in, stream->avail_out,
		 req->avail_in - stream->avail_in, ret);
	req->next_in = stream->next_in;
	req->avail_in = stream->avail_in;
	req->next_out = stream->next_out;
	req->avail_out = stream->avail_out;
	return ret;
}

static int zlib_compress_final(struct crypto_pcomp *tfm,
			       struct comp_request *req)
{
	int ret;
	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &dctx->comp_stream;

	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
	stream->next_in = req->next_in;
	stream->avail_in = req->avail_in;
	stream->next_out = req->next_out;
	stream->avail_out = req->avail_out;

	ret = zlib_deflate(stream, Z_FINISH);
	if (ret != Z_STREAM_END) {
		pr_debug("zlib_deflate failed %d\n", ret);
		return -EINVAL;
	}

	ret = req->avail_out - stream->avail_out;
	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
		 stream->avail_in, stream->avail_out,
		 req->avail_in - stream->avail_in, ret);
	req->next_in = stream->next_in;
	req->avail_in = stream->avail_in;
	req->next_out = stream->next_out;
	req->avail_out = stream->avail_out;
	return ret;
}


static int zlib_decompress_setup(struct crypto_pcomp *tfm, void *params,
				 unsigned int len)
{
	struct zlib_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &ctx->decomp_stream;
	struct nlattr *tb[ZLIB_DECOMP_MAX + 1];
	int ret = 0;

	ret = nla_parse(tb, ZLIB_DECOMP_MAX, params, len, NULL);
	if (ret)
		return ret;

	zlib_decomp_exit(ctx);

	ctx->decomp_windowBits = tb[ZLIB_DECOMP_WINDOWBITS]
				 ? nla_get_u32(tb[ZLIB_DECOMP_WINDOWBITS])
				 : DEF_WBITS;

	stream->workspace = kzalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
	if (!stream->workspace)
		return -ENOMEM;

	ret = zlib_inflateInit2(stream, ctx->decomp_windowBits);
	if (ret != Z_OK) {
		kfree(stream->workspace);
		stream->workspace = NULL;
		return -EINVAL;
	}

	return 0;
}

static int zlib_decompress_init(struct crypto_pcomp *tfm)
{
	int ret;
	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &dctx->decomp_stream;

	ret = zlib_inflateReset(stream);
	if (ret != Z_OK)
		return -EINVAL;

	return 0;
}

static int zlib_decompress_update(struct crypto_pcomp *tfm,
				  struct comp_request *req)
{
	int ret;
	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &dctx->decomp_stream;

	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
	stream->next_in = req->next_in;
	stream->avail_in = req->avail_in;
	stream->next_out = req->next_out;
	stream->avail_out = req->avail_out;

	ret = zlib_inflate(stream, Z_SYNC_FLUSH);
	switch (ret) {
	case Z_OK:
	case Z_STREAM_END:
		break;

	case Z_BUF_ERROR:
		pr_debug("zlib_inflate could not make progress\n");
		return -EAGAIN;

	default:
		pr_debug("zlib_inflate failed %d\n", ret);
		return -EINVAL;
	}

	ret = req->avail_out - stream->avail_out;
	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
		 stream->avail_in, stream->avail_out,
		 req->avail_in - stream->avail_in, ret);
	req->next_in = stream->next_in;
	req->avail_in = stream->avail_in;
	req->next_out = stream->next_out;
	req->avail_out = stream->avail_out;
	return ret;
}

static int zlib_decompress_final(struct crypto_pcomp *tfm,
				 struct comp_request *req)
{
	int ret;
	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	struct z_stream_s *stream = &dctx->decomp_stream;

	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
	stream->next_in = req->next_in;
	stream->avail_in = req->avail_in;
	stream->next_out = req->next_out;
	stream->avail_out = req->avail_out;

	if (dctx->decomp_windowBits < 0) {
		ret = zlib_inflate(stream, Z_SYNC_FLUSH);
		/*
		 * Work around a bug in zlib, which sometimes wants to taste an
		 * extra byte when being used in the (undocumented) raw deflate
		 * mode. (From USAGI).
		 */
		if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
			const void *saved_next_in = stream->next_in;
			u8 zerostuff = 0;

			stream->next_in = &zerostuff;
			stream->avail_in = 1;
			ret = zlib_inflate(stream, Z_FINISH);
			stream->next_in = saved_next_in;
			stream->avail_in = 0;
		}
	} else
		ret = zlib_inflate(stream, Z_FINISH);
	if (ret != Z_STREAM_END) {
		pr_debug("zlib_inflate failed %d\n", ret);
		return -EINVAL;
	}

	ret = req->avail_out - stream->avail_out;
	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
		 stream->avail_in, stream->avail_out,
		 req->avail_in - stream->avail_in, ret);
	req->next_in = stream->next_in;
	req->avail_in = stream->avail_in;
	req->next_out = stream->next_out;
	req->avail_out = stream->avail_out;
	return ret;
}


static struct pcomp_alg zlib_alg = {
	.compress_setup		= zlib_compress_setup,
	.compress_init		= zlib_compress_init,
	.compress_update	= zlib_compress_update,
	.compress_final		= zlib_compress_final,
	.decompress_setup	= zlib_decompress_setup,
	.decompress_init	= zlib_decompress_init,
	.decompress_update	= zlib_decompress_update,
	.decompress_final	= zlib_decompress_final,

	.base			= {
		.cra_name	= "zlib",
		.cra_flags	= CRYPTO_ALG_TYPE_PCOMPRESS,
		.cra_ctxsize	= sizeof(struct zlib_ctx),
		.cra_module	= THIS_MODULE,
		.cra_init	= zlib_init,
		.cra_exit	= zlib_exit,
	}
};

static int __init zlib_mod_init(void)
{
	return crypto_register_pcomp(&zlib_alg);
}

static void __exit zlib_mod_fini(void)
{
	crypto_unregister_pcomp(&zlib_alg);
}

module_init(zlib_mod_init);
module_exit(zlib_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Zlib Compression Algorithm");
MODULE_AUTHOR("Sony Corporation");
Commit	Line	Data
bf68e65e GU	1	/*
	2	* Cryptographic API.
	3	*
	4	* Zlib algorithm
	5	*
	6	* Copyright 2008 Sony Corporation
	7	*
	8	* Based on deflate.c, which is
	9	* Copyright (c) 2003 James Morris <[email protected]>
	10	*
	11	* This program is free software; you can redistribute it and/or modify it
	12	* under the terms of the GNU General Public License as published by the Free
	13	* Software Foundation; either version 2 of the License, or (at your option)
	14	* any later version.
	15	*
	16	* FIXME: deflate transforms will require up to a total of about 436k of kernel
	17	* memory on i386 (390k for compression, the rest for decompression), as the
	18	* current zlib kernel code uses a worst case pre-allocation system by default.
	19	* This needs to be fixed so that the amount of memory required is properly
	20	* related to the winbits and memlevel parameters.
	21	*/
	22
	23	#define pr_fmt(fmt) "%s: " fmt, __func__
	24
	25	#include <linux/init.h>
	26	#include <linux/module.h>
	27	#include <linux/zlib.h>
	28	#include <linux/vmalloc.h>
	29	#include <linux/interrupt.h>
	30	#include <linux/mm.h>
	31	#include <linux/net.h>
	32	#include <linux/slab.h>
	33
	34	#include <crypto/internal/compress.h>
	35
	36	#include <net/netlink.h>
	37
	38
	39	struct zlib_ctx {
	40	struct z_stream_s comp_stream;
	41	struct z_stream_s decomp_stream;
	42	int decomp_windowBits;
	43	};
	44
	45
	46	static void zlib_comp_exit(struct zlib_ctx *ctx)
	47	{
	48	struct z_stream_s *stream = &ctx->comp_stream;
	49
	50	if (stream->workspace) {
	51	zlib_deflateEnd(stream);
	52	vfree(stream->workspace);
	53	stream->workspace = NULL;
	54	}
	55	}
	56
	57	static void zlib_decomp_exit(struct zlib_ctx *ctx)
	58	{
	59	struct z_stream_s *stream = &ctx->decomp_stream;
	60
	61	if (stream->workspace) {
	62	zlib_inflateEnd(stream);
	63	kfree(stream->workspace);
	64	stream->workspace = NULL;
65	}
66	}
67
68	static int zlib_init(struct crypto_tfm *tfm)
69	{
70	return 0;
71	}
72
73	static void zlib_exit(struct crypto_tfm *tfm)
74	{
75	struct zlib_ctx *ctx = crypto_tfm_ctx(tfm);
76
77	zlib_comp_exit(ctx);
78	zlib_decomp_exit(ctx);
79	}
80
81
82	static int zlib_compress_setup(struct crypto_pcomp tfm, void params,
83	unsigned int len)
84	{
85	struct zlib_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
86	struct z_stream_s *stream = &ctx->comp_stream;
87	struct nlattr *tb[ZLIB_COMP_MAX + 1];
88	size_t workspacesize;
89	int ret;
90
91	ret = nla_parse(tb, ZLIB_COMP_MAX, params, len, NULL);
92	if (ret)
93	return ret;
94
95	zlib_comp_exit(ctx);
96
97	workspacesize = zlib_deflate_workspacesize();
98	stream->workspace = vmalloc(workspacesize);
99	if (!stream->workspace)
100	return -ENOMEM;
101
102	memset(stream->workspace, 0, workspacesize);
103	ret = zlib_deflateInit2(stream,
104	tb[ZLIB_COMP_LEVEL]
105	? nla_get_u32(tb[ZLIB_COMP_LEVEL])
106	: Z_DEFAULT_COMPRESSION,
107	tb[ZLIB_COMP_METHOD]
108	? nla_get_u32(tb[ZLIB_COMP_METHOD])
109	: Z_DEFLATED,
110	tb[ZLIB_COMP_WINDOWBITS]
111	? nla_get_u32(tb[ZLIB_COMP_WINDOWBITS])
112	: MAX_WBITS,
113	tb[ZLIB_COMP_MEMLEVEL]
114	? nla_get_u32(tb[ZLIB_COMP_MEMLEVEL])
115	: DEF_MEM_LEVEL,
116	tb[ZLIB_COMP_STRATEGY]
117	? nla_get_u32(tb[ZLIB_COMP_STRATEGY])
118	: Z_DEFAULT_STRATEGY);
119	if (ret != Z_OK) {
120	vfree(stream->workspace);
121	stream->workspace = NULL;
122	return -EINVAL;
123	}
124
125	return 0;
126	}
127
128	static int zlib_compress_init(struct crypto_pcomp *tfm)
129	{
130	int ret;
131	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
132	struct z_stream_s *stream = &dctx->comp_stream;
133
134	ret = zlib_deflateReset(stream);
135	if (ret != Z_OK)
136	return -EINVAL;
137
138	return 0;
139	}
140
141	static int zlib_compress_update(struct crypto_pcomp *tfm,
142	struct comp_request *req)
143	{
144	int ret;
145	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
146	struct z_stream_s *stream = &dctx->comp_stream;
147
148	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
149	stream->next_in = req->next_in;
150	stream->avail_in = req->avail_in;
151	stream->next_out = req->next_out;
152	stream->avail_out = req->avail_out;
153
154	ret = zlib_deflate(stream, Z_NO_FLUSH);
155	switch (ret) {
156	case Z_OK:
157	break;
158
159	case Z_BUF_ERROR:
160	pr_debug("zlib_deflate could not make progress\n");
161	return -EAGAIN;
162
163	default:
164	pr_debug("zlib_deflate failed %d\n", ret);
165	return -EINVAL;
166	}
167
3ce858cb	168	ret = req->avail_out - stream->avail_out;
bf68e65e GU	169	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
bf68e65e GU	170	stream->avail_in, stream->avail_out,
3ce858cb	171	req->avail_in - stream->avail_in, ret);
bf68e65e GU	172	req->next_in = stream->next_in;
	173	req->avail_in = stream->avail_in;
	174	req->next_out = stream->next_out;
	175	req->avail_out = stream->avail_out;
3ce858cb	176	return ret;
bf68e65e GU	177	}
	178
	179	static int zlib_compress_final(struct crypto_pcomp *tfm,
	180	struct comp_request *req)
	181	{
	182	int ret;
	183	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	184	struct z_stream_s *stream = &dctx->comp_stream;
	185
	186	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
	187	stream->next_in = req->next_in;
	188	stream->avail_in = req->avail_in;
	189	stream->next_out = req->next_out;
	190	stream->avail_out = req->avail_out;
	191
	192	ret = zlib_deflate(stream, Z_FINISH);
	193	if (ret != Z_STREAM_END) {
	194	pr_debug("zlib_deflate failed %d\n", ret);
	195	return -EINVAL;
	196	}
	197
3ce858cb	198	ret = req->avail_out - stream->avail_out;
bf68e65e GU	199	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
bf68e65e GU	200	stream->avail_in, stream->avail_out,
3ce858cb	201	req->avail_in - stream->avail_in, ret);
bf68e65e GU	202	req->next_in = stream->next_in;
	203	req->avail_in = stream->avail_in;
	204	req->next_out = stream->next_out;
	205	req->avail_out = stream->avail_out;
3ce858cb	206	return ret;
bf68e65e GU	207	}
	208
	209
	210	static int zlib_decompress_setup(struct crypto_pcomp tfm, void params,
	211	unsigned int len)
	212	{
	213	struct zlib_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	214	struct z_stream_s *stream = &ctx->decomp_stream;
	215	struct nlattr *tb[ZLIB_DECOMP_MAX + 1];
	216	int ret = 0;
	217
	218	ret = nla_parse(tb, ZLIB_DECOMP_MAX, params, len, NULL);
	219	if (ret)
	220	return ret;
	221
	222	zlib_decomp_exit(ctx);
	223
	224	ctx->decomp_windowBits = tb[ZLIB_DECOMP_WINDOWBITS]
	225	? nla_get_u32(tb[ZLIB_DECOMP_WINDOWBITS])
	226	: DEF_WBITS;
	227
	228	stream->workspace = kzalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
	229	if (!stream->workspace)
	230	return -ENOMEM;
	231
	232	ret = zlib_inflateInit2(stream, ctx->decomp_windowBits);
	233	if (ret != Z_OK) {
	234	kfree(stream->workspace);
	235	stream->workspace = NULL;
	236	return -EINVAL;
	237	}
	238
	239	return 0;
	240	}
	241
	242	static int zlib_decompress_init(struct crypto_pcomp *tfm)
	243	{
	244	int ret;
	245	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	246	struct z_stream_s *stream = &dctx->decomp_stream;
	247
	248	ret = zlib_inflateReset(stream);
	249	if (ret != Z_OK)
	250	return -EINVAL;
	251
	252	return 0;
	253	}
	254
	255	static int zlib_decompress_update(struct crypto_pcomp *tfm,
	256	struct comp_request *req)
	257	{
	258	int ret;
	259	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	260	struct z_stream_s *stream = &dctx->decomp_stream;
	261
	262	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
	263	stream->next_in = req->next_in;
	264	stream->avail_in = req->avail_in;
	265	stream->next_out = req->next_out;
	266	stream->avail_out = req->avail_out;
	267
	268	ret = zlib_inflate(stream, Z_SYNC_FLUSH);
	269	switch (ret) {
	270	case Z_OK:
271	case Z_STREAM_END:
272	break;
273
274	case Z_BUF_ERROR:
275	pr_debug("zlib_inflate could not make progress\n");
276	return -EAGAIN;
277
278	default:
279	pr_debug("zlib_inflate failed %d\n", ret);
280	return -EINVAL;
281	}
282
3ce858cb	283	ret = req->avail_out - stream->avail_out;
bf68e65e GU	284	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
bf68e65e GU	285	stream->avail_in, stream->avail_out,
3ce858cb	286	req->avail_in - stream->avail_in, ret);
bf68e65e GU	287	req->next_in = stream->next_in;
	288	req->avail_in = stream->avail_in;
	289	req->next_out = stream->next_out;
	290	req->avail_out = stream->avail_out;
3ce858cb	291	return ret;
bf68e65e GU	292	}
	293
	294	static int zlib_decompress_final(struct crypto_pcomp *tfm,
	295	struct comp_request *req)
	296	{
	297	int ret;
	298	struct zlib_ctx *dctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
	299	struct z_stream_s *stream = &dctx->decomp_stream;
	300
	301	pr_debug("avail_in %u, avail_out %u\n", req->avail_in, req->avail_out);
	302	stream->next_in = req->next_in;
	303	stream->avail_in = req->avail_in;
	304	stream->next_out = req->next_out;
	305	stream->avail_out = req->avail_out;
	306
	307	if (dctx->decomp_windowBits < 0) {
	308	ret = zlib_inflate(stream, Z_SYNC_FLUSH);
	309	/*
	310	* Work around a bug in zlib, which sometimes wants to taste an
	311	* extra byte when being used in the (undocumented) raw deflate
	312	* mode. (From USAGI).
	313	*/
	314	if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
	315	const void *saved_next_in = stream->next_in;
	316	u8 zerostuff = 0;
	317
	318	stream->next_in = &zerostuff;
	319	stream->avail_in = 1;
	320	ret = zlib_inflate(stream, Z_FINISH);
	321	stream->next_in = saved_next_in;
	322	stream->avail_in = 0;
	323	}
	324	} else
	325	ret = zlib_inflate(stream, Z_FINISH);
	326	if (ret != Z_STREAM_END) {
	327	pr_debug("zlib_inflate failed %d\n", ret);
	328	return -EINVAL;
	329	}
	330
3ce858cb	331	ret = req->avail_out - stream->avail_out;
bf68e65e GU	332	pr_debug("avail_in %u, avail_out %u (consumed %u, produced %u)\n",
bf68e65e GU	333	stream->avail_in, stream->avail_out,
3ce858cb	334	req->avail_in - stream->avail_in, ret);
bf68e65e GU	335	req->next_in = stream->next_in;
	336	req->avail_in = stream->avail_in;
	337	req->next_out = stream->next_out;
	338	req->avail_out = stream->avail_out;
3ce858cb	339	return ret;
bf68e65e GU	340	}
	341
	342
	343	static struct pcomp_alg zlib_alg = {
	344	.compress_setup = zlib_compress_setup,
	345	.compress_init = zlib_compress_init,
	346	.compress_update = zlib_compress_update,
	347	.compress_final = zlib_compress_final,
	348	.decompress_setup = zlib_decompress_setup,
	349	.decompress_init = zlib_decompress_init,
	350	.decompress_update = zlib_decompress_update,
	351	.decompress_final = zlib_decompress_final,
	352
	353	.base = {
	354	.cra_name = "zlib",
	355	.cra_flags = CRYPTO_ALG_TYPE_PCOMPRESS,
	356	.cra_ctxsize = sizeof(struct zlib_ctx),
	357	.cra_module = THIS_MODULE,
	358	.cra_init = zlib_init,
	359	.cra_exit = zlib_exit,
	360	}
	361	};
	362
	363	static int __init zlib_mod_init(void)
	364	{
	365	return crypto_register_pcomp(&zlib_alg);
	366	}
	367
	368	static void __exit zlib_mod_fini(void)
	369	{
	370	crypto_unregister_pcomp(&zlib_alg);
	371	}
	372
	373	module_init(zlib_mod_init);
	374	module_exit(zlib_mod_fini);
	375
	376	MODULE_LICENSE("GPL");
	377	MODULE_DESCRIPTION("Zlib Compression Algorithm");
	378	MODULE_AUTHOR("Sony Corporation");