1 /* 2 * Cryptographic API. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 as published by 6 * the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; if not, write to the Free Software Foundation, Inc., 51 15 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 16 * 17 */ 18 19 #include <linux/init.h> 20 #include <linux/module.h> 21 #include <linux/crypto.h> 22 #include <linux/vmalloc.h> 23 #include <linux/lzo.h> 24 25 struct lzo_ctx { 26 void *lzo_comp_mem; 27 }; 28 29 static int lzo_init(struct crypto_tfm *tfm) 30 { 31 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); 32 33 ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS); 34 if (!ctx->lzo_comp_mem) 35 return -ENOMEM; 36 37 return 0; 38 } 39 40 static void lzo_exit(struct crypto_tfm *tfm) 41 { 42 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); 43 44 vfree(ctx->lzo_comp_mem); 45 } 46 47 static int lzo_compress(struct crypto_tfm *tfm, const u8 *src, 48 unsigned int slen, u8 *dst, unsigned int *dlen) 49 { 50 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); 51 size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ 52 int err; 53 54 err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx->lzo_comp_mem); 55 56 if (err != LZO_E_OK) 57 return -EINVAL; 58 59 *dlen = tmp_len; 60 return 0; 61 } 62 63 static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src, 64 unsigned int slen, u8 *dst, unsigned int *dlen) 65 { 66 int err; 67 size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ 68 69 err = lzo1x_decompress_safe(src, slen, dst, &tmp_len); 70 71 if (err != LZO_E_OK) 72 return -EINVAL; 73 74 *dlen = tmp_len; 75 return 0; 76 77 } 78 79 static struct crypto_alg alg = { 80 .cra_name = "lzo", 81 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, 82 .cra_ctxsize = sizeof(struct lzo_ctx), 83 .cra_module = THIS_MODULE, 84 .cra_list = LIST_HEAD_INIT(alg.cra_list), 85 .cra_init = lzo_init, 86 .cra_exit = lzo_exit, 87 .cra_u = { .compress = { 88 .coa_compress = lzo_compress, 89 .coa_decompress = lzo_decompress } } 90 }; 91 92 static int __init lzo_mod_init(void) 93 { 94 return crypto_register_alg(&alg); 95 } 96 97 static void __exit lzo_mod_fini(void) 98 { 99 crypto_unregister_alg(&alg); 100 } 101 102 module_init(lzo_mod_init); 103 module_exit(lzo_mod_fini); 104 105 MODULE_LICENSE("GPL"); 106 MODULE_DESCRIPTION("LZO Compression Algorithm"); 107