/* * Cryptographic API. * * Copyright (c) 2017-present, Facebook, Inc. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. */ #include <linux/crypto.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/net.h> #include <linux/vmalloc.h> #include <linux/zstd.h> #include <crypto/internal/scompress.h> #define ZSTD_DEF_LEVEL 3 struct zstd_ctx { ZSTD_CCtx *cctx; ZSTD_DCtx *dctx; void *cwksp; void *dwksp; }; static ZSTD_parameters zstd_params(void) { return ZSTD_getParams(ZSTD_DEF_LEVEL, 0, 0); } static int zstd_comp_init(struct zstd_ctx *ctx) { int ret = 0; const ZSTD_parameters params = zstd_params(); const size_t wksp_size = ZSTD_CCtxWorkspaceBound(params.cParams); ctx->cwksp = vzalloc(wksp_size); if (!ctx->cwksp) { ret = -ENOMEM; goto out; } ctx->cctx = ZSTD_initCCtx(ctx->cwksp, wksp_size); if (!ctx->cctx) { ret = -EINVAL; goto out_free; } out: return ret; out_free: vfree(ctx->cwksp); goto out; } static int zstd_decomp_init(struct zstd_ctx *ctx) { int ret = 0; const size_t wksp_size = ZSTD_DCtxWorkspaceBound(); ctx->dwksp = vzalloc(wksp_size); if (!ctx->dwksp) { ret = -ENOMEM; goto out; } ctx->dctx = ZSTD_initDCtx(ctx->dwksp, wksp_size); if (!ctx->dctx) { ret = -EINVAL; goto out_free; } out: return ret; out_free: vfree(ctx->dwksp); goto out; } static void zstd_comp_exit(struct zstd_ctx *ctx) { vfree(ctx->cwksp); ctx->cwksp = NULL; ctx->cctx = NULL; } static void zstd_decomp_exit(struct zstd_ctx *ctx) { vfree(ctx->dwksp); ctx->dwksp = NULL; ctx->dctx = NULL; } static int __zstd_init(void *ctx) { int ret; ret = zstd_comp_init(ctx); if (ret) return ret; ret = zstd_decomp_init(ctx); if (ret) zstd_comp_exit(ctx); return ret; } static void *zstd_alloc_ctx(struct crypto_scomp *tfm) { int ret; struct zstd_ctx *ctx; ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); if (!ctx) return ERR_PTR(-ENOMEM); ret = __zstd_init(ctx); if (ret) { kfree(ctx); return ERR_PTR(ret); } return ctx; } static int zstd_init(struct crypto_tfm *tfm) { struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); return __zstd_init(ctx); } static void __zstd_exit(void *ctx) { zstd_comp_exit(ctx); zstd_decomp_exit(ctx); } static void zstd_free_ctx(struct crypto_scomp *tfm, void *ctx) { __zstd_exit(ctx); kzfree(ctx); } static void zstd_exit(struct crypto_tfm *tfm) { struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); __zstd_exit(ctx); } static int __zstd_compress(const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen, void *ctx) { size_t out_len; struct zstd_ctx *zctx = ctx; const ZSTD_parameters params = zstd_params(); out_len = ZSTD_compressCCtx(zctx->cctx, dst, *dlen, src, slen, params); if (ZSTD_isError(out_len)) return -EINVAL; *dlen = out_len; return 0; } static int zstd_compress(struct crypto_tfm *tfm, const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen) { struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); return __zstd_compress(src, slen, dst, dlen, ctx); } static int zstd_scompress(struct crypto_scomp *tfm, const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen, void *ctx) { return __zstd_compress(src, slen, dst, dlen, ctx); } static int __zstd_decompress(const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen, void *ctx) { size_t out_len; struct zstd_ctx *zctx = ctx; out_len = ZSTD_decompressDCtx(zctx->dctx, dst, *dlen, src, slen); if (ZSTD_isError(out_len)) return -EINVAL; *dlen = out_len; return 0; } static int zstd_decompress(struct crypto_tfm *tfm, const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen) { struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); return __zstd_decompress(src, slen, dst, dlen, ctx); } static int zstd_sdecompress(struct crypto_scomp *tfm, const u8 *src, unsigned int slen, u8 *dst, unsigned int *dlen, void *ctx) { return __zstd_decompress(src, slen, dst, dlen, ctx); } static struct crypto_alg alg = { .cra_name = "zstd", .cra_driver_name = "zstd-generic", .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, .cra_ctxsize = sizeof(struct zstd_ctx), .cra_module = THIS_MODULE, .cra_init = zstd_init, .cra_exit = zstd_exit, .cra_u = { .compress = { .coa_compress = zstd_compress, .coa_decompress = zstd_decompress } } }; static struct scomp_alg scomp = { .alloc_ctx = zstd_alloc_ctx, .free_ctx = zstd_free_ctx, .compress = zstd_scompress, .decompress = zstd_sdecompress, .base = { .cra_name = "zstd", .cra_driver_name = "zstd-scomp", .cra_module = THIS_MODULE, } }; static int __init zstd_mod_init(void) { int ret; ret = crypto_register_alg(&alg); if (ret) return ret; ret = crypto_register_scomp(&scomp); if (ret) crypto_unregister_alg(&alg); return ret; } static void __exit zstd_mod_fini(void) { crypto_unregister_alg(&alg); crypto_unregister_scomp(&scomp); } subsys_initcall(zstd_mod_init); module_exit(zstd_mod_fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Zstd Compression Algorithm"); MODULE_ALIAS_CRYPTO("zstd");