1 files changed, 160 insertions, 0 deletions
diff --git a/crypto/lz4.c b/crypto/lz4.c
new file mode 100644
index 000000000..0606f8862
--- /dev/null
+++ b/crypto/lz4.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Cryptographic API.
+ *
+ * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/vmalloc.h>
+#include <linux/lz4.h>
+#include <crypto/internal/scompress.h>
+
+struct lz4_ctx {
+	void *lz4_comp_mem;
+};
+
+static void *lz4_alloc_ctx(struct crypto_scomp *tfm)
+{
+	void *ctx;
+
+	ctx = vmalloc(LZ4_MEM_COMPRESS);
+	if (!ctx)
+		return ERR_PTR(-ENOMEM);
+
+	return ctx;
+}
+
+static int lz4_init(struct crypto_tfm *tfm)
+{
+	struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	ctx->lz4_comp_mem = lz4_alloc_ctx(NULL);
+	if (IS_ERR(ctx->lz4_comp_mem))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void lz4_free_ctx(struct crypto_scomp *tfm, void *ctx)
+{
+	vfree(ctx);
+}
+
+static void lz4_exit(struct crypto_tfm *tfm)
+{
+	struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	lz4_free_ctx(NULL, ctx->lz4_comp_mem);
+}
+
+static int __lz4_compress_crypto(const u8 *src, unsigned int slen,
+				 u8 *dst, unsigned int *dlen, void *ctx)
+{
+	int out_len = LZ4_compress_default(src, dst,
+		slen, *dlen, ctx);
+
+	if (!out_len)
+		return -EINVAL;
+
+	*dlen = out_len;
+	return 0;
+}
+
+static int lz4_scompress(struct crypto_scomp *tfm, const u8 *src,
+			 unsigned int slen, u8 *dst, unsigned int *dlen,
+			 void *ctx)
+{
+	return __lz4_compress_crypto(src, slen, dst, dlen, ctx);
+}
+
+static int lz4_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
+			       unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+	struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	return __lz4_compress_crypto(src, slen, dst, dlen, ctx->lz4_comp_mem);
+}
+
+static int __lz4_decompress_crypto(const u8 *src, unsigned int slen,
+				   u8 *dst, unsigned int *dlen, void *ctx)
+{
+	int out_len = LZ4_decompress_safe(src, dst, slen, *dlen);
+
+	if (out_len < 0)
+		return -EINVAL;
+
+	*dlen = out_len;
+	return 0;
+}
+
+static int lz4_sdecompress(struct crypto_scomp *tfm, const u8 *src,
+			   unsigned int slen, u8 *dst, unsigned int *dlen,
+			   void *ctx)
+{
+	return __lz4_decompress_crypto(src, slen, dst, dlen, NULL);
+}
+
+static int lz4_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
+				 unsigned int slen, u8 *dst,
+				 unsigned int *dlen)
+{
+	return __lz4_decompress_crypto(src, slen, dst, dlen, NULL);
+}
+
+static struct crypto_alg alg_lz4 = {
+	.cra_name		= "lz4",
+	.cra_driver_name	= "lz4-generic",
+	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
+	.cra_ctxsize		= sizeof(struct lz4_ctx),
+	.cra_module		= THIS_MODULE,
+	.cra_init		= lz4_init,
+	.cra_exit		= lz4_exit,
+	.cra_u			= { .compress = {
+	.coa_compress		= lz4_compress_crypto,
+	.coa_decompress		= lz4_decompress_crypto } }
+};
+
+static struct scomp_alg scomp = {
+	.alloc_ctx		= lz4_alloc_ctx,
+	.free_ctx		= lz4_free_ctx,
+	.compress		= lz4_scompress,
+	.decompress		= lz4_sdecompress,
+	.base			= {
+		.cra_name	= "lz4",
+		.cra_driver_name = "lz4-scomp",
+		.cra_module	 = THIS_MODULE,
+	}
+};
+
+static int __init lz4_mod_init(void)
+{
+	int ret;
+
+	ret = crypto_register_alg(&alg_lz4);
+	if (ret)
+		return ret;
+
+	ret = crypto_register_scomp(&scomp);
+	if (ret) {
+		crypto_unregister_alg(&alg_lz4);
+		return ret;
+	}
+
+	return ret;
+}
+
+static void __exit lz4_mod_fini(void)
+{
+	crypto_unregister_alg(&alg_lz4);
+	crypto_unregister_scomp(&scomp);
+}
+
+subsys_initcall(lz4_mod_init);
+module_exit(lz4_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZ4 Compression Algorithm");
+MODULE_ALIAS_CRYPTO("lz4");