/* * 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 lz4_ctx { void *lz4_comp_mem; }; static int lz4_init(struct crypto_tfm *tfm) { struct lz4_ctx *ctx = crypto_tfm_ctx(tfm); ctx->lz4_comp_mem = vmalloc(LZ4_MEM_COMPRESS); if (!ctx->lz4_comp_mem) return -ENOMEM; return 0; } static void lz4_exit(struct crypto_tfm *tfm) { struct lz4_ctx *ctx = crypto_tfm_ctx(tfm); vfree(ctx->lz4_comp_mem); } 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); size_t tmp_len = *dlen; int err; err = lz4_compress(src, slen, dst, &tmp_len, ctx->lz4_comp_mem); if (err < 0) return -EINVAL; *dlen = tmp_len; return 0; } static int lz4_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_unknownoutputsize(src, __slen, dst, &tmp_len); if (err < 0) return -EINVAL; *dlen = tmp_len; return err; } static struct crypto_alg alg_lz4 = { .cra_name = "lz4", .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, .cra_ctxsize = sizeof(struct lz4_ctx), .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(alg_lz4.cra_list), .cra_init = lz4_init, .cra_exit = lz4_exit, .cra_u = { .compress = { .coa_compress = lz4_compress_crypto, .coa_decompress = lz4_decompress_crypto } } }; static int __init lz4_mod_init(void) { return crypto_register_alg(&alg_lz4); } static void __exit lz4_mod_fini(void) { crypto_unregister_alg(&alg_lz4); } module_init(lz4_mod_init); module_exit(lz4_mod_fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("LZ4 Compression Algorithm"); MODULE_ALIAS_CRYPTO("lz4");