[CRYPTO] lzo: Add LZO compression algorithm support

Add LZO compression algorithm support

Signed-off-by: Zoltan Sogor <weth@inf.u-szeged.hu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 106 insertions, 0 deletions

diff --git a/crypto/lzo.c b/crypto/lzo.c
new file mode 100644
index 0000000..48c3288
--- /dev/null
+++ b/crypto/lzo.c
@@ -0,0 +1,106 @@
+/*
+ * Cryptographic API.
+ *
+ * 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/lzo.h>
+
+struct lzo_ctx {
+	void *lzo_comp_mem;
+};
+
+static int lzo_init(struct crypto_tfm *tfm)
+{
+	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS);
+	if (!ctx->lzo_comp_mem)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void lzo_exit(struct crypto_tfm *tfm)
+{
+	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	vfree(ctx->lzo_comp_mem);
+}
+
+static int lzo_compress(struct crypto_tfm *tfm, const u8 *src,
+			    unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
+	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
+	int err;
+
+	err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx->lzo_comp_mem);
+
+	if (err != LZO_E_OK)
+		return -EINVAL;
+
+	*dlen = tmp_len;
+	return 0;
+}
+
+static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src,
+			      unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+	int err;
+	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
+
+	err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);
+
+	if (err != LZO_E_OK)
+		return -EINVAL;
+
+	*dlen = tmp_len;
+	return 0;
+
+}
+
+static struct crypto_alg alg = {
+	.cra_name		= "lzo",
+	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
+	.cra_ctxsize		= sizeof(struct lzo_ctx),
+	.cra_module		= THIS_MODULE,
+	.cra_list		= LIST_HEAD_INIT(alg.cra_list),
+	.cra_init		= lzo_init,
+	.cra_exit		= lzo_exit,
+	.cra_u			= { .compress = {
+	.coa_compress 		= lzo_compress,
+	.coa_decompress  	= lzo_decompress } }
+};
+
+static int __init init(void)
+{
+	return crypto_register_alg(&alg);
+}
+
+static void __exit fini(void)
+{
+	crypto_unregister_alg(&alg);
+}
+
+module_init(init);
+module_exit(fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZO Compression Algorithm");