/*
|
/*
|
* Cryptographic API.
|
* Cryptographic API.
|
*
|
*
|
* Deflate algorithm (RFC 1951), implemented here primarily for use
|
* Deflate algorithm (RFC 1951), implemented here primarily for use
|
* by IPCOMP (RFC 3173 & RFC 2394).
|
* by IPCOMP (RFC 3173 & RFC 2394).
|
*
|
*
|
* Copyright (c) 2003 James Morris <jmorris@intercode.com.au>
|
* Copyright (c) 2003 James Morris <jmorris@intercode.com.au>
|
*
|
*
|
* This program is free software; you can redistribute it and/or modify it
|
* 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
|
* 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)
|
* Software Foundation; either version 2 of the License, or (at your option)
|
* any later version.
|
* any later version.
|
*
|
*
|
* FIXME: deflate transforms will require up to a total of about 436k of kernel
|
* 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
|
* 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.
|
* 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
|
* This needs to be fixed so that the amount of memory required is properly
|
* related to the winbits and memlevel parameters.
|
* related to the winbits and memlevel parameters.
|
*
|
*
|
* The default winbits of 11 should suit most packets, and it may be something
|
* The default winbits of 11 should suit most packets, and it may be something
|
* to configure on a per-tfm basis in the future.
|
* to configure on a per-tfm basis in the future.
|
*
|
*
|
* Currently, compression history is not maintained between tfm calls, as
|
* Currently, compression history is not maintained between tfm calls, as
|
* it is not needed for IPCOMP and keeps the code simpler. It can be
|
* it is not needed for IPCOMP and keeps the code simpler. It can be
|
* implemented if someone wants it.
|
* implemented if someone wants it.
|
*/
|
*/
|
#include <linux/init.h>
|
#include <linux/init.h>
|
#include <linux/module.h>
|
#include <linux/module.h>
|
#include <linux/crypto.h>
|
#include <linux/crypto.h>
|
#include <linux/zlib.h>
|
#include <linux/zlib.h>
|
#include <linux/vmalloc.h>
|
#include <linux/vmalloc.h>
|
#include <linux/interrupt.h>
|
#include <linux/interrupt.h>
|
#include <linux/mm.h>
|
#include <linux/mm.h>
|
#include <linux/net.h>
|
#include <linux/net.h>
|
#include <linux/slab.h>
|
#include <linux/slab.h>
|
|
|
#define DEFLATE_DEF_LEVEL Z_DEFAULT_COMPRESSION
|
#define DEFLATE_DEF_LEVEL Z_DEFAULT_COMPRESSION
|
#define DEFLATE_DEF_WINBITS 11
|
#define DEFLATE_DEF_WINBITS 11
|
#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
|
#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
|
|
|
struct deflate_ctx {
|
struct deflate_ctx {
|
int comp_initialized;
|
int comp_initialized;
|
int decomp_initialized;
|
int decomp_initialized;
|
struct z_stream_s comp_stream;
|
struct z_stream_s comp_stream;
|
struct z_stream_s decomp_stream;
|
struct z_stream_s decomp_stream;
|
};
|
};
|
|
|
static inline int deflate_gfp(void)
|
static inline int deflate_gfp(void)
|
{
|
{
|
return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
|
return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
|
}
|
}
|
|
|
static int deflate_init(void *ctx)
|
static int deflate_init(void *ctx)
|
{
|
{
|
return 0;
|
return 0;
|
}
|
}
|
|
|
static void deflate_exit(void *ctx)
|
static void deflate_exit(void *ctx)
|
{
|
{
|
struct deflate_ctx *dctx = ctx;
|
struct deflate_ctx *dctx = ctx;
|
|
|
if (dctx->comp_initialized)
|
if (dctx->comp_initialized)
|
vfree(dctx->comp_stream.workspace);
|
vfree(dctx->comp_stream.workspace);
|
if (dctx->decomp_initialized)
|
if (dctx->decomp_initialized)
|
kfree(dctx->decomp_stream.workspace);
|
kfree(dctx->decomp_stream.workspace);
|
}
|
}
|
|
|
/*
|
/*
|
* Lazy initialization to make interface simple without allocating
|
* Lazy initialization to make interface simple without allocating
|
* un-needed workspaces. Thus can be called in softirq context.
|
* un-needed workspaces. Thus can be called in softirq context.
|
*/
|
*/
|
static int deflate_comp_init(struct deflate_ctx *ctx)
|
static int deflate_comp_init(struct deflate_ctx *ctx)
|
{
|
{
|
int ret = 0;
|
int ret = 0;
|
struct z_stream_s *stream = &ctx->comp_stream;
|
struct z_stream_s *stream = &ctx->comp_stream;
|
|
|
stream->workspace = __vmalloc(zlib_deflate_workspacesize(),
|
stream->workspace = __vmalloc(zlib_deflate_workspacesize(),
|
deflate_gfp()|__GFP_HIGHMEM,
|
deflate_gfp()|__GFP_HIGHMEM,
|
PAGE_KERNEL);
|
PAGE_KERNEL);
|
if (!stream->workspace ) {
|
if (!stream->workspace ) {
|
ret = -ENOMEM;
|
ret = -ENOMEM;
|
goto out;
|
goto out;
|
}
|
}
|
memset(stream->workspace, 0, zlib_deflate_workspacesize());
|
memset(stream->workspace, 0, zlib_deflate_workspacesize());
|
ret = zlib_deflateInit2(stream, DEFLATE_DEF_LEVEL, Z_DEFLATED,
|
ret = zlib_deflateInit2(stream, DEFLATE_DEF_LEVEL, Z_DEFLATED,
|
-DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL,
|
-DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL,
|
Z_DEFAULT_STRATEGY);
|
Z_DEFAULT_STRATEGY);
|
if (ret != Z_OK) {
|
if (ret != Z_OK) {
|
ret = -EINVAL;
|
ret = -EINVAL;
|
goto out_free;
|
goto out_free;
|
}
|
}
|
ctx->comp_initialized = 1;
|
ctx->comp_initialized = 1;
|
out:
|
out:
|
return ret;
|
return ret;
|
out_free:
|
out_free:
|
vfree(stream->workspace);
|
vfree(stream->workspace);
|
goto out;
|
goto out;
|
}
|
}
|
|
|
static int deflate_decomp_init(struct deflate_ctx *ctx)
|
static int deflate_decomp_init(struct deflate_ctx *ctx)
|
{
|
{
|
int ret = 0;
|
int ret = 0;
|
struct z_stream_s *stream = &ctx->decomp_stream;
|
struct z_stream_s *stream = &ctx->decomp_stream;
|
|
|
stream->workspace = kmalloc(zlib_inflate_workspacesize(),
|
stream->workspace = kmalloc(zlib_inflate_workspacesize(),
|
deflate_gfp());
|
deflate_gfp());
|
if (!stream->workspace ) {
|
if (!stream->workspace ) {
|
ret = -ENOMEM;
|
ret = -ENOMEM;
|
goto out;
|
goto out;
|
}
|
}
|
memset(stream->workspace, 0, zlib_inflate_workspacesize());
|
memset(stream->workspace, 0, zlib_inflate_workspacesize());
|
ret = zlib_inflateInit2(stream, -DEFLATE_DEF_WINBITS);
|
ret = zlib_inflateInit2(stream, -DEFLATE_DEF_WINBITS);
|
if (ret != Z_OK) {
|
if (ret != Z_OK) {
|
ret = -EINVAL;
|
ret = -EINVAL;
|
goto out_free;
|
goto out_free;
|
}
|
}
|
ctx->decomp_initialized = 1;
|
ctx->decomp_initialized = 1;
|
out:
|
out:
|
return ret;
|
return ret;
|
out_free:
|
out_free:
|
kfree(stream->workspace);
|
kfree(stream->workspace);
|
goto out;
|
goto out;
|
}
|
}
|
|
|
static int deflate_compress(void *ctx, const u8 *src, unsigned int slen,
|
static int deflate_compress(void *ctx, const u8 *src, unsigned int slen,
|
u8 *dst, unsigned int *dlen)
|
u8 *dst, unsigned int *dlen)
|
{
|
{
|
int ret = 0;
|
int ret = 0;
|
struct deflate_ctx *dctx = ctx;
|
struct deflate_ctx *dctx = ctx;
|
struct z_stream_s *stream = &dctx->comp_stream;
|
struct z_stream_s *stream = &dctx->comp_stream;
|
|
|
if (!dctx->comp_initialized) {
|
if (!dctx->comp_initialized) {
|
ret = deflate_comp_init(dctx);
|
ret = deflate_comp_init(dctx);
|
if (ret)
|
if (ret)
|
goto out;
|
goto out;
|
}
|
}
|
|
|
ret = zlib_deflateReset(stream);
|
ret = zlib_deflateReset(stream);
|
if (ret != Z_OK) {
|
if (ret != Z_OK) {
|
ret = -EINVAL;
|
ret = -EINVAL;
|
goto out;
|
goto out;
|
}
|
}
|
|
|
stream->next_in = (u8 *)src;
|
stream->next_in = (u8 *)src;
|
stream->avail_in = slen;
|
stream->avail_in = slen;
|
stream->next_out = (u8 *)dst;
|
stream->next_out = (u8 *)dst;
|
stream->avail_out = *dlen;
|
stream->avail_out = *dlen;
|
|
|
ret = zlib_deflate(stream, Z_FINISH);
|
ret = zlib_deflate(stream, Z_FINISH);
|
if (ret != Z_STREAM_END) {
|
if (ret != Z_STREAM_END) {
|
ret = -EINVAL;
|
ret = -EINVAL;
|
goto out;
|
goto out;
|
}
|
}
|
ret = 0;
|
ret = 0;
|
*dlen = stream->total_out;
|
*dlen = stream->total_out;
|
out:
|
out:
|
return ret;
|
return ret;
|
}
|
}
|
|
|
static int deflate_decompress(void *ctx, const u8 *src, unsigned int slen,
|
static int deflate_decompress(void *ctx, const u8 *src, unsigned int slen,
|
u8 *dst, unsigned int *dlen)
|
u8 *dst, unsigned int *dlen)
|
{
|
{
|
|
|
int ret = 0;
|
int ret = 0;
|
struct deflate_ctx *dctx = ctx;
|
struct deflate_ctx *dctx = ctx;
|
struct z_stream_s *stream = &dctx->decomp_stream;
|
struct z_stream_s *stream = &dctx->decomp_stream;
|
|
|
if (!dctx->decomp_initialized) {
|
if (!dctx->decomp_initialized) {
|
ret = deflate_decomp_init(dctx);
|
ret = deflate_decomp_init(dctx);
|
if (ret)
|
if (ret)
|
goto out;
|
goto out;
|
}
|
}
|
|
|
ret = zlib_inflateReset(stream);
|
ret = zlib_inflateReset(stream);
|
if (ret != Z_OK) {
|
if (ret != Z_OK) {
|
ret = -EINVAL;
|
ret = -EINVAL;
|
goto out;
|
goto out;
|
}
|
}
|
|
|
stream->next_in = (u8 *)src;
|
stream->next_in = (u8 *)src;
|
stream->avail_in = slen;
|
stream->avail_in = slen;
|
stream->next_out = (u8 *)dst;
|
stream->next_out = (u8 *)dst;
|
stream->avail_out = *dlen;
|
stream->avail_out = *dlen;
|
|
|
ret = zlib_inflate(stream, Z_SYNC_FLUSH);
|
ret = zlib_inflate(stream, Z_SYNC_FLUSH);
|
/*
|
/*
|
* Work around a bug in zlib, which sometimes wants to taste an extra
|
* Work around a bug in zlib, which sometimes wants to taste an extra
|
* byte when being used in the (undocumented) raw deflate mode.
|
* byte when being used in the (undocumented) raw deflate mode.
|
* (From USAGI).
|
* (From USAGI).
|
*/
|
*/
|
if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
|
if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
|
u8 zerostuff = 0;
|
u8 zerostuff = 0;
|
stream->next_in = &zerostuff;
|
stream->next_in = &zerostuff;
|
stream->avail_in = 1;
|
stream->avail_in = 1;
|
ret = zlib_inflate(stream, Z_FINISH);
|
ret = zlib_inflate(stream, Z_FINISH);
|
}
|
}
|
if (ret != Z_STREAM_END) {
|
if (ret != Z_STREAM_END) {
|
ret = -EINVAL;
|
ret = -EINVAL;
|
goto out;
|
goto out;
|
}
|
}
|
ret = 0;
|
ret = 0;
|
*dlen = stream->total_out;
|
*dlen = stream->total_out;
|
out:
|
out:
|
return ret;
|
return ret;
|
}
|
}
|
|
|
static struct crypto_alg alg = {
|
static struct crypto_alg alg = {
|
.cra_name = "deflate",
|
.cra_name = "deflate",
|
.cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
|
.cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
|
.cra_ctxsize = sizeof(struct deflate_ctx),
|
.cra_ctxsize = sizeof(struct deflate_ctx),
|
.cra_module = THIS_MODULE,
|
.cra_module = THIS_MODULE,
|
.cra_list = LIST_HEAD_INIT(alg.cra_list),
|
.cra_list = LIST_HEAD_INIT(alg.cra_list),
|
.cra_u = { .compress = {
|
.cra_u = { .compress = {
|
.coa_init = deflate_init,
|
.coa_init = deflate_init,
|
.coa_exit = deflate_exit,
|
.coa_exit = deflate_exit,
|
.coa_compress = deflate_compress,
|
.coa_compress = deflate_compress,
|
.coa_decompress = deflate_decompress } }
|
.coa_decompress = deflate_decompress } }
|
};
|
};
|
|
|
static int __init init(void)
|
static int __init init(void)
|
{
|
{
|
return crypto_register_alg(&alg);
|
return crypto_register_alg(&alg);
|
}
|
}
|
|
|
static void __exit fini(void)
|
static void __exit fini(void)
|
{
|
{
|
crypto_unregister_alg(&alg);
|
crypto_unregister_alg(&alg);
|
}
|
}
|
|
|
module_init(init);
|
module_init(init);
|
module_exit(fini);
|
module_exit(fini);
|
|
|
MODULE_LICENSE("GPL");
|
MODULE_LICENSE("GPL");
|
MODULE_DESCRIPTION("Deflate Compression Algorithm for IPCOMP");
|
MODULE_DESCRIPTION("Deflate Compression Algorithm for IPCOMP");
|
MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
|
MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
|
|
|
|
|
