crypto: add lz4 Cryptographic API

[cascardo/linux.git] / crypto / lz4hc.c

diff --git a/crypto/lz4hc.c b/crypto/lz4hc.c
new file mode 100644 (file)
index 0000000..151ba31
--- /dev/null
+++ b/crypto/lz4hc.c
@@ -0,0 +1,106 @@
+/*
+ * Cryptographic API.
+ *
+ * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/vmalloc.h>
+#include <linux/lz4.h>
+
+struct lz4hc_ctx {
+       void *lz4hc_comp_mem;
+};
+
+static int lz4hc_init(struct crypto_tfm *tfm)
+{
+       struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
+
+       ctx->lz4hc_comp_mem = vmalloc(LZ4HC_MEM_COMPRESS);
+       if (!ctx->lz4hc_comp_mem)
+               return -ENOMEM;
+
+       return 0;
+}
+
+static void lz4hc_exit(struct crypto_tfm *tfm)
+{
+       struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
+
+       vfree(ctx->lz4hc_comp_mem);
+}
+
+static int lz4hc_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
+                           unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+       struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
+       size_t tmp_len = *dlen;
+       int err;
+
+       err = lz4hc_compress(src, slen, dst, &tmp_len, ctx->lz4hc_comp_mem);
+
+       if (err < 0)
+               return -EINVAL;
+
+       *dlen = tmp_len;
+       return 0;
+}
+
+static int lz4hc_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
+                             unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+       int err;
+       size_t tmp_len = *dlen;
+       size_t __slen = slen;
+
+       err = lz4_decompress(src, &__slen, dst, tmp_len);
+       if (err < 0)
+               return -EINVAL;
+
+       *dlen = tmp_len;
+       return err;
+}
+
+static struct crypto_alg alg_lz4hc = {
+       .cra_name               = "lz4hc",
+       .cra_flags              = CRYPTO_ALG_TYPE_COMPRESS,
+       .cra_ctxsize            = sizeof(struct lz4hc_ctx),
+       .cra_module             = THIS_MODULE,
+       .cra_list               = LIST_HEAD_INIT(alg_lz4hc.cra_list),
+       .cra_init               = lz4hc_init,
+       .cra_exit               = lz4hc_exit,
+       .cra_u                  = { .compress = {
+       .coa_compress           = lz4hc_compress_crypto,
+       .coa_decompress         = lz4hc_decompress_crypto } }
+};
+
+static int __init lz4hc_mod_init(void)
+{
+       return crypto_register_alg(&alg_lz4hc);
+}
+
+static void __exit lz4hc_mod_fini(void)
+{
+       crypto_unregister_alg(&alg_lz4hc);
+}
+
+module_init(lz4hc_mod_init);
+module_exit(lz4hc_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZ4HC Compression Algorithm");