// SPDX-License-Identifier: GPL-2.0-only
/*
 * Cryptographic API.
 */

#include <crypto/internal/scompress.h>
#include <linux/init.h>
#include <linux/lzo.h>
#include <linux/module.h>
#include <linux/slab.h>

static void *lzorle_alloc_ctx(void)
{
        void *ctx;

        ctx = kvmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
        if (!ctx)
                return ERR_PTR(-ENOMEM);

        return ctx;
}

static void lzorle_free_ctx(void *ctx)
{
        kvfree(ctx);
}

static int __lzorle_compress(const u8 *src, unsigned int slen,
                          u8 *dst, unsigned int *dlen, void *ctx)
{
        size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
        int err;

        err = lzorle1x_1_compress_safe(src, slen, dst, &tmp_len, ctx);

        if (err != LZO_E_OK)
                return -EINVAL;

        *dlen = tmp_len;
        return 0;
}

static int lzorle_scompress(struct crypto_scomp *tfm, const u8 *src,
                         unsigned int slen, u8 *dst, unsigned int *dlen,
                         void *ctx)
{
        return __lzorle_compress(src, slen, dst, dlen, ctx);
}

static int __lzorle_decompress(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 int lzorle_sdecompress(struct crypto_scomp *tfm, const u8 *src,
                           unsigned int slen, u8 *dst, unsigned int *dlen,
                           void *ctx)
{
        return __lzorle_decompress(src, slen, dst, dlen);
}

static struct scomp_alg scomp = {
        .streams                = {
                .alloc_ctx      = lzorle_alloc_ctx,
                .free_ctx       = lzorle_free_ctx,
        },
        .compress               = lzorle_scompress,
        .decompress             = lzorle_sdecompress,
        .base                   = {
                .cra_name       = "lzo-rle",
                .cra_driver_name = "lzo-rle-scomp",
                .cra_module      = THIS_MODULE,
        }
};

static int __init lzorle_mod_init(void)
{
        return crypto_register_scomp(&scomp);
}

static void __exit lzorle_mod_fini(void)
{
        crypto_unregister_scomp(&scomp);
}

module_init(lzorle_mod_init);
module_exit(lzorle_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZO-RLE Compression Algorithm");
MODULE_ALIAS_CRYPTO("lzo-rle");