| /* |
| * 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 <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; |
| } |
| |
| 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, |
| req->avail_out - stream->avail_out); |
| 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 0; |
| } |
| |
| 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; |
| } |
| |
| 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, |
| req->avail_out - stream->avail_out); |
| 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 0; |
| } |
| |
| |
| 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; |
| } |
| |
| 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, |
| req->avail_out - stream->avail_out); |
| 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 0; |
| } |
| |
| 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; |
| } |
| |
| 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, |
| req->avail_out - stream->avail_out); |
| 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 0; |
| } |
| |
| |
| 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"); |