1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Cryptographic API. 4 * 5 * Copyright (c) 2013 Chanho Min <chanho.min@lge.com> 6 */ 7 8 #include <linux/init.h> 9 #include <linux/module.h> 10 #include <linux/crypto.h> 11 #include <linux/vmalloc.h> 12 #include <linux/lz4.h> 13 #include <crypto/internal/scompress.h> 14 15 struct lz4_ctx { 16 void *lz4_comp_mem; 17 }; 18 19 static void *lz4_alloc_ctx(struct crypto_scomp *tfm) 20 { 21 void *ctx; 22 23 ctx = vmalloc(LZ4_MEM_COMPRESS); 24 if (!ctx) 25 return ERR_PTR(-ENOMEM); 26 27 return ctx; 28 } 29 30 static int lz4_init(struct crypto_tfm *tfm) 31 { 32 struct lz4_ctx *ctx = crypto_tfm_ctx(tfm); 33 34 ctx->lz4_comp_mem = lz4_alloc_ctx(NULL); 35 if (IS_ERR(ctx->lz4_comp_mem)) 36 return -ENOMEM; 37 38 return 0; 39 } 40 41 static void lz4_free_ctx(struct crypto_scomp *tfm, void *ctx) 42 { 43 vfree(ctx); 44 } 45 46 static void lz4_exit(struct crypto_tfm *tfm) 47 { 48 struct lz4_ctx *ctx = crypto_tfm_ctx(tfm); 49 50 lz4_free_ctx(NULL, ctx->lz4_comp_mem); 51 } 52 53 static int __lz4_compress_crypto(const u8 *src, unsigned int slen, 54 u8 *dst, unsigned int *dlen, void *ctx) 55 { 56 int out_len = LZ4_compress_default(src, dst, 57 slen, *dlen, ctx); 58 59 if (!out_len) 60 return -EINVAL; 61 62 *dlen = out_len; 63 return 0; 64 } 65 66 static int lz4_scompress(struct crypto_scomp *tfm, const u8 *src, 67 unsigned int slen, u8 *dst, unsigned int *dlen, 68 void *ctx) 69 { 70 return __lz4_compress_crypto(src, slen, dst, dlen, ctx); 71 } 72 73 static int lz4_compress_crypto(struct crypto_tfm *tfm, const u8 *src, 74 unsigned int slen, u8 *dst, unsigned int *dlen) 75 { 76 struct lz4_ctx *ctx = crypto_tfm_ctx(tfm); 77 78 return __lz4_compress_crypto(src, slen, dst, dlen, ctx->lz4_comp_mem); 79 } 80 81 static int __lz4_decompress_crypto(const u8 *src, unsigned int slen, 82 u8 *dst, unsigned int *dlen, void *ctx) 83 { 84 int out_len = LZ4_decompress_safe(src, dst, slen, *dlen); 85 86 if (out_len < 0) 87 return -EINVAL; 88 89 *dlen = out_len; 90 return 0; 91 } 92 93 static int lz4_sdecompress(struct crypto_scomp *tfm, const u8 *src, 94 unsigned int slen, u8 *dst, unsigned int *dlen, 95 void *ctx) 96 { 97 return __lz4_decompress_crypto(src, slen, dst, dlen, NULL); 98 } 99 100 static int lz4_decompress_crypto(struct crypto_tfm *tfm, const u8 *src, 101 unsigned int slen, u8 *dst, 102 unsigned int *dlen) 103 { 104 return __lz4_decompress_crypto(src, slen, dst, dlen, NULL); 105 } 106 107 static struct crypto_alg alg_lz4 = { 108 .cra_name = "lz4", 109 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, 110 .cra_ctxsize = sizeof(struct lz4_ctx), 111 .cra_module = THIS_MODULE, 112 .cra_init = lz4_init, 113 .cra_exit = lz4_exit, 114 .cra_u = { .compress = { 115 .coa_compress = lz4_compress_crypto, 116 .coa_decompress = lz4_decompress_crypto } } 117 }; 118 119 static struct scomp_alg scomp = { 120 .alloc_ctx = lz4_alloc_ctx, 121 .free_ctx = lz4_free_ctx, 122 .compress = lz4_scompress, 123 .decompress = lz4_sdecompress, 124 .base = { 125 .cra_name = "lz4", 126 .cra_driver_name = "lz4-scomp", 127 .cra_module = THIS_MODULE, 128 } 129 }; 130 131 static int __init lz4_mod_init(void) 132 { 133 int ret; 134 135 ret = crypto_register_alg(&alg_lz4); 136 if (ret) 137 return ret; 138 139 ret = crypto_register_scomp(&scomp); 140 if (ret) { 141 crypto_unregister_alg(&alg_lz4); 142 return ret; 143 } 144 145 return ret; 146 } 147 148 static void __exit lz4_mod_fini(void) 149 { 150 crypto_unregister_alg(&alg_lz4); 151 crypto_unregister_scomp(&scomp); 152 } 153 154 subsys_initcall(lz4_mod_init); 155 module_exit(lz4_mod_fini); 156 157 MODULE_LICENSE("GPL"); 158 MODULE_DESCRIPTION("LZ4 Compression Algorithm"); 159 MODULE_ALIAS_CRYPTO("lz4"); 160