/* * Cryptographic API. * * Zlib algorithm * * Copyright 2008 Sony Corporation * * Based on deflate.c, which is * Copyright (c) 2003 James Morris <jmorris@intercode.com.au> * * 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 <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);		vfree(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];	int window_bits, mem_level;	size_t workspacesize;	int ret; 	ret = nla_parse(tb, ZLIB_COMP_MAX, params, len, NULL);	if (ret)		return ret; 	zlib_comp_exit(ctx); 	window_bits = tb[ZLIB_COMP_WINDOWBITS]					? nla_get_u32(tb[ZLIB_COMP_WINDOWBITS])					: MAX_WBITS;	mem_level = tb[ZLIB_COMP_MEMLEVEL]					? nla_get_u32(tb[ZLIB_COMP_MEMLEVEL])					: DEF_MEM_LEVEL; 	workspacesize = zlib_deflate_workspacesize(window_bits, mem_level);	stream->workspace = vzalloc(workspacesize);	if (!stream->workspace)		return -ENOMEM; 	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,				window_bits,				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 = vzalloc(zlib_inflate_workspacesize());	if (!stream->workspace)		return -ENOMEM; 	ret = zlib_inflateInit2(stream, ctx->decomp_windowBits);	if (ret != Z_OK) {		vfree(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");