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/mm.h> 24 #include <linux/lzo.h> 25 #include <crypto/internal/scompress.h> 26 27 struct lzo_ctx { 28 void *lzo_comp_mem; 29 }; 30 31 static void *lzo_alloc_ctx(struct crypto_scomp *tfm) 32 { 33 void *ctx; 34 35 ctx = kmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL | __GFP_NOWARN); 36 if (!ctx) 37 ctx = vmalloc(LZO1X_MEM_COMPRESS); 38 if (!ctx) 39 return ERR_PTR(-ENOMEM); 40 41 return ctx; 42 } 43 44 static int lzo_init(struct crypto_tfm *tfm) 45 { 46 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); 47 48 ctx->lzo_comp_mem = lzo_alloc_ctx(NULL); 49 if (IS_ERR(ctx->lzo_comp_mem)) 50 return -ENOMEM; 51 52 return 0; 53 } 54 55 static void lzo_free_ctx(struct crypto_scomp *tfm, void *ctx) 56 { 57 kvfree(ctx); 58 } 59 60 static void lzo_exit(struct crypto_tfm *tfm) 61 { 62 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); 63 64 lzo_free_ctx(NULL, ctx->lzo_comp_mem); 65 } 66 67 static int __lzo_compress(const u8 *src, unsigned int slen, 68 u8 *dst, unsigned int *dlen, void *ctx) 69 { 70 size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ 71 int err; 72 73 err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx); 74 75 if (err != LZO_E_OK) 76 return -EINVAL; 77 78 *dlen = tmp_len; 79 return 0; 80 } 81 82 static int lzo_compress(struct crypto_tfm *tfm, const u8 *src, 83 unsigned int slen, u8 *dst, unsigned int *dlen) 84 { 85 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); 86 87 return __lzo_compress(src, slen, dst, dlen, ctx->lzo_comp_mem); 88 } 89 90 static int lzo_scompress(struct crypto_scomp *tfm, const u8 *src, 91 unsigned int slen, u8 *dst, unsigned int *dlen, 92 void *ctx) 93 { 94 return __lzo_compress(src, slen, dst, dlen, ctx); 95 } 96 97 static int __lzo_decompress(const u8 *src, unsigned int slen, 98 u8 *dst, unsigned int *dlen) 99 { 100 int err; 101 size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ 102 103 err = lzo1x_decompress_safe(src, slen, dst, &tmp_len); 104 105 if (err != LZO_E_OK) 106 return -EINVAL; 107 108 *dlen = tmp_len; 109 return 0; 110 } 111 112 static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src, 113 unsigned int slen, u8 *dst, unsigned int *dlen) 114 { 115 return __lzo_decompress(src, slen, dst, dlen); 116 } 117 118 static int lzo_sdecompress(struct crypto_scomp *tfm, const u8 *src, 119 unsigned int slen, u8 *dst, unsigned int *dlen, 120 void *ctx) 121 { 122 return __lzo_decompress(src, slen, dst, dlen); 123 } 124 125 static struct crypto_alg alg = { 126 .cra_name = "lzo", 127 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, 128 .cra_ctxsize = sizeof(struct lzo_ctx), 129 .cra_module = THIS_MODULE, 130 .cra_init = lzo_init, 131 .cra_exit = lzo_exit, 132 .cra_u = { .compress = { 133 .coa_compress = lzo_compress, 134 .coa_decompress = lzo_decompress } } 135 }; 136 137 static struct scomp_alg scomp = { 138 .alloc_ctx = lzo_alloc_ctx, 139 .free_ctx = lzo_free_ctx, 140 .compress = lzo_scompress, 141 .decompress = lzo_sdecompress, 142 .base = { 143 .cra_name = "lzo", 144 .cra_driver_name = "lzo-scomp", 145 .cra_module = THIS_MODULE, 146 } 147 }; 148 149 static int __init lzo_mod_init(void) 150 { 151 int ret; 152 153 ret = crypto_register_alg(&alg); 154 if (ret) 155 return ret; 156 157 ret = crypto_register_scomp(&scomp); 158 if (ret) { 159 crypto_unregister_alg(&alg); 160 return ret; 161 } 162 163 return ret; 164 } 165 166 static void __exit lzo_mod_fini(void) 167 { 168 crypto_unregister_alg(&alg); 169 crypto_unregister_scomp(&scomp); 170 } 171 172 module_init(lzo_mod_init); 173 module_exit(lzo_mod_fini); 174 175 MODULE_LICENSE("GPL"); 176 MODULE_DESCRIPTION("LZO Compression Algorithm"); 177 MODULE_ALIAS_CRYPTO("lzo"); 178