linux/crypto/deflate.c
Eric Biggers d6ebf5286f crypto: make all generic algorithms set cra_driver_name
Most generic crypto algorithms declare a driver name ending in
"-generic".  The rest don't declare a driver name and instead rely on
the crypto API automagically appending "-generic" upon registration.

Having multiple conventions is unnecessarily confusing and makes it
harder to grep for all generic algorithms in the kernel source tree.
But also, allowing NULL driver names is problematic because sometimes
people fail to set it, e.g. the case fixed by commit 4179803643
("crypto: cavium/zip - fix collision with generic cra_driver_name").

Of course, people can also incorrectly name their drivers "-generic".
But that's much easier to notice / grep for.

Therefore, let's make cra_driver_name mandatory.  In preparation for
this, this patch makes all generic algorithms set cra_driver_name.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-06-13 14:31:39 +08:00

345 lines
7.9 KiB
C

/*
* Cryptographic API.
*
* Deflate algorithm (RFC 1951), implemented here primarily for use
* by IPCOMP (RFC 3173 & RFC 2394).
*
* 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.
*
* The default winbits of 11 should suit most packets, and it may be something
* to configure on a per-tfm basis in the future.
*
* Currently, compression history is not maintained between tfm calls, as
* it is not needed for IPCOMP and keeps the code simpler. It can be
* implemented if someone wants it.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/crypto.h>
#include <linux/zlib.h>
#include <linux/vmalloc.h>
#include <linux/interrupt.h>
#include <linux/mm.h>
#include <linux/net.h>
#include <crypto/internal/scompress.h>
#define DEFLATE_DEF_LEVEL Z_DEFAULT_COMPRESSION
#define DEFLATE_DEF_WINBITS 11
#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
struct deflate_ctx {
struct z_stream_s comp_stream;
struct z_stream_s decomp_stream;
};
static int deflate_comp_init(struct deflate_ctx *ctx, int format)
{
int ret = 0;
struct z_stream_s *stream = &ctx->comp_stream;
stream->workspace = vzalloc(zlib_deflate_workspacesize(
MAX_WBITS, MAX_MEM_LEVEL));
if (!stream->workspace) {
ret = -ENOMEM;
goto out;
}
if (format)
ret = zlib_deflateInit(stream, 3);
else
ret = zlib_deflateInit2(stream, DEFLATE_DEF_LEVEL, Z_DEFLATED,
-DEFLATE_DEF_WINBITS,
DEFLATE_DEF_MEMLEVEL,
Z_DEFAULT_STRATEGY);
if (ret != Z_OK) {
ret = -EINVAL;
goto out_free;
}
out:
return ret;
out_free:
vfree(stream->workspace);
goto out;
}
static int deflate_decomp_init(struct deflate_ctx *ctx, int format)
{
int ret = 0;
struct z_stream_s *stream = &ctx->decomp_stream;
stream->workspace = vzalloc(zlib_inflate_workspacesize());
if (!stream->workspace) {
ret = -ENOMEM;
goto out;
}
if (format)
ret = zlib_inflateInit(stream);
else
ret = zlib_inflateInit2(stream, -DEFLATE_DEF_WINBITS);
if (ret != Z_OK) {
ret = -EINVAL;
goto out_free;
}
out:
return ret;
out_free:
vfree(stream->workspace);
goto out;
}
static void deflate_comp_exit(struct deflate_ctx *ctx)
{
zlib_deflateEnd(&ctx->comp_stream);
vfree(ctx->comp_stream.workspace);
}
static void deflate_decomp_exit(struct deflate_ctx *ctx)
{
zlib_inflateEnd(&ctx->decomp_stream);
vfree(ctx->decomp_stream.workspace);
}
static int __deflate_init(void *ctx, int format)
{
int ret;
ret = deflate_comp_init(ctx, format);
if (ret)
goto out;
ret = deflate_decomp_init(ctx, format);
if (ret)
deflate_comp_exit(ctx);
out:
return ret;
}
static void *gen_deflate_alloc_ctx(struct crypto_scomp *tfm, int format)
{
struct deflate_ctx *ctx;
int ret;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return ERR_PTR(-ENOMEM);
ret = __deflate_init(ctx, format);
if (ret) {
kfree(ctx);
return ERR_PTR(ret);
}
return ctx;
}
static void *deflate_alloc_ctx(struct crypto_scomp *tfm)
{
return gen_deflate_alloc_ctx(tfm, 0);
}
static void *zlib_deflate_alloc_ctx(struct crypto_scomp *tfm)
{
return gen_deflate_alloc_ctx(tfm, 1);
}
static int deflate_init(struct crypto_tfm *tfm)
{
struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
return __deflate_init(ctx, 0);
}
static void __deflate_exit(void *ctx)
{
deflate_comp_exit(ctx);
deflate_decomp_exit(ctx);
}
static void deflate_free_ctx(struct crypto_scomp *tfm, void *ctx)
{
__deflate_exit(ctx);
kzfree(ctx);
}
static void deflate_exit(struct crypto_tfm *tfm)
{
struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
__deflate_exit(ctx);
}
static int __deflate_compress(const u8 *src, unsigned int slen,
u8 *dst, unsigned int *dlen, void *ctx)
{
int ret = 0;
struct deflate_ctx *dctx = ctx;
struct z_stream_s *stream = &dctx->comp_stream;
ret = zlib_deflateReset(stream);
if (ret != Z_OK) {
ret = -EINVAL;
goto out;
}
stream->next_in = (u8 *)src;
stream->avail_in = slen;
stream->next_out = (u8 *)dst;
stream->avail_out = *dlen;
ret = zlib_deflate(stream, Z_FINISH);
if (ret != Z_STREAM_END) {
ret = -EINVAL;
goto out;
}
ret = 0;
*dlen = stream->total_out;
out:
return ret;
}
static int deflate_compress(struct crypto_tfm *tfm, const u8 *src,
unsigned int slen, u8 *dst, unsigned int *dlen)
{
struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
return __deflate_compress(src, slen, dst, dlen, dctx);
}
static int deflate_scompress(struct crypto_scomp *tfm, const u8 *src,
unsigned int slen, u8 *dst, unsigned int *dlen,
void *ctx)
{
return __deflate_compress(src, slen, dst, dlen, ctx);
}
static int __deflate_decompress(const u8 *src, unsigned int slen,
u8 *dst, unsigned int *dlen, void *ctx)
{
int ret = 0;
struct deflate_ctx *dctx = ctx;
struct z_stream_s *stream = &dctx->decomp_stream;
ret = zlib_inflateReset(stream);
if (ret != Z_OK) {
ret = -EINVAL;
goto out;
}
stream->next_in = (u8 *)src;
stream->avail_in = slen;
stream->next_out = (u8 *)dst;
stream->avail_out = *dlen;
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) {
u8 zerostuff = 0;
stream->next_in = &zerostuff;
stream->avail_in = 1;
ret = zlib_inflate(stream, Z_FINISH);
}
if (ret != Z_STREAM_END) {
ret = -EINVAL;
goto out;
}
ret = 0;
*dlen = stream->total_out;
out:
return ret;
}
static int deflate_decompress(struct crypto_tfm *tfm, const u8 *src,
unsigned int slen, u8 *dst, unsigned int *dlen)
{
struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
return __deflate_decompress(src, slen, dst, dlen, dctx);
}
static int deflate_sdecompress(struct crypto_scomp *tfm, const u8 *src,
unsigned int slen, u8 *dst, unsigned int *dlen,
void *ctx)
{
return __deflate_decompress(src, slen, dst, dlen, ctx);
}
static struct crypto_alg alg = {
.cra_name = "deflate",
.cra_driver_name = "deflate-generic",
.cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
.cra_ctxsize = sizeof(struct deflate_ctx),
.cra_module = THIS_MODULE,
.cra_init = deflate_init,
.cra_exit = deflate_exit,
.cra_u = { .compress = {
.coa_compress = deflate_compress,
.coa_decompress = deflate_decompress } }
};
static struct scomp_alg scomp[] = { {
.alloc_ctx = deflate_alloc_ctx,
.free_ctx = deflate_free_ctx,
.compress = deflate_scompress,
.decompress = deflate_sdecompress,
.base = {
.cra_name = "deflate",
.cra_driver_name = "deflate-scomp",
.cra_module = THIS_MODULE,
}
}, {
.alloc_ctx = zlib_deflate_alloc_ctx,
.free_ctx = deflate_free_ctx,
.compress = deflate_scompress,
.decompress = deflate_sdecompress,
.base = {
.cra_name = "zlib-deflate",
.cra_driver_name = "zlib-deflate-scomp",
.cra_module = THIS_MODULE,
}
} };
static int __init deflate_mod_init(void)
{
int ret;
ret = crypto_register_alg(&alg);
if (ret)
return ret;
ret = crypto_register_scomps(scomp, ARRAY_SIZE(scomp));
if (ret) {
crypto_unregister_alg(&alg);
return ret;
}
return ret;
}
static void __exit deflate_mod_fini(void)
{
crypto_unregister_alg(&alg);
crypto_unregister_scomps(scomp, ARRAY_SIZE(scomp));
}
subsys_initcall(deflate_mod_init);
module_exit(deflate_mod_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Deflate Compression Algorithm for IPCOMP");
MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
MODULE_ALIAS_CRYPTO("deflate");