1 files changed, 258 insertions, 0 deletions
diff --git a/crypto/zstd.c b/crypto/zstd.c
new file mode 100644
index 000000000..1a3309f06
--- /dev/null
+++ b/crypto/zstd.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Cryptographic API.
+ *
+ * Copyright (c) 2017-present, Facebook, Inc.
+ */
+#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);
+	kfree_sensitive(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");