/* * 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> #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_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); } module_init(lz4_mod_init); module_exit(lz4_mod_fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("LZ4 Compression Algorithm"); MODULE_ALIAS_CRYPTO("lz4");