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 #include <linux/init.h> 8 #include <linux/module.h> 9 #include <linux/crypto.h> 10 #include <linux/vmalloc.h> 11 #include <linux/lz4.h> 12 #include <crypto/internal/scompress.h> 13 14 struct lz4hc_ctx { 15 void *lz4hc_comp_mem; 16 }; 17 18 static void *lz4hc_alloc_ctx(struct crypto_scomp *tfm) 19 { 20 void *ctx; 21 22 ctx = vmalloc(LZ4HC_MEM_COMPRESS); 23 if (!ctx) 24 return ERR_PTR(-ENOMEM); 25 26 return ctx; 27 } 28 29 static int lz4hc_init(struct crypto_tfm *tfm) 30 { 31 struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm); 32 33 ctx->lz4hc_comp_mem = lz4hc_alloc_ctx(NULL); 34 if (IS_ERR(ctx->lz4hc_comp_mem)) 35 return -ENOMEM; 36 37 return 0; 38 } 39 40 static void lz4hc_free_ctx(struct crypto_scomp *tfm, void *ctx) 41 { 42 vfree(ctx); 43 } 44 45 static void lz4hc_exit(struct crypto_tfm *tfm) 46 { 47 struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm); 48 49 lz4hc_free_ctx(NULL, ctx->lz4hc_comp_mem); 50 } 51 52 static int __lz4hc_compress_crypto(const u8 *src, unsigned int slen, 53 u8 *dst, unsigned int *dlen, void *ctx) 54 { 55 int out_len = LZ4_compress_HC(src, dst, slen, 56 *dlen, LZ4HC_DEFAULT_CLEVEL, ctx); 57 58 if (!out_len) 59 return -EINVAL; 60 61 *dlen = out_len; 62 return 0; 63 } 64 65 static int lz4hc_scompress(struct crypto_scomp *tfm, const u8 *src, 66 unsigned int slen, u8 *dst, unsigned int *dlen, 67 void *ctx) 68 { 69 return __lz4hc_compress_crypto(src, slen, dst, dlen, ctx); 70 } 71 72 static int lz4hc_compress_crypto(struct crypto_tfm *tfm, const u8 *src, 73 unsigned int slen, u8 *dst, 74 unsigned int *dlen) 75 { 76 struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm); 77 78 return __lz4hc_compress_crypto(src, slen, dst, dlen, 79 ctx->lz4hc_comp_mem); 80 } 81 82 static int __lz4hc_decompress_crypto(const u8 *src, unsigned int slen, 83 u8 *dst, unsigned int *dlen, void *ctx) 84 { 85 int out_len = LZ4_decompress_safe(src, dst, slen, *dlen); 86 87 if (out_len < 0) 88 return -EINVAL; 89 90 *dlen = out_len; 91 return 0; 92 } 93 94 static int lz4hc_sdecompress(struct crypto_scomp *tfm, const u8 *src, 95 unsigned int slen, u8 *dst, unsigned int *dlen, 96 void *ctx) 97 { 98 return __lz4hc_decompress_crypto(src, slen, dst, dlen, NULL); 99 } 100 101 static int lz4hc_decompress_crypto(struct crypto_tfm *tfm, const u8 *src, 102 unsigned int slen, u8 *dst, 103 unsigned int *dlen) 104 { 105 return __lz4hc_decompress_crypto(src, slen, dst, dlen, NULL); 106 } 107 108 static struct crypto_alg alg_lz4hc = { 109 .cra_name = "lz4hc", 110 .cra_driver_name = "lz4hc-generic", 111 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, 112 .cra_ctxsize = sizeof(struct lz4hc_ctx), 113 .cra_module = THIS_MODULE, 114 .cra_init = lz4hc_init, 115 .cra_exit = lz4hc_exit, 116 .cra_u = { .compress = { 117 .coa_compress = lz4hc_compress_crypto, 118 .coa_decompress = lz4hc_decompress_crypto } } 119 }; 120 121 static struct scomp_alg scomp = { 122 .alloc_ctx = lz4hc_alloc_ctx, 123 .free_ctx = lz4hc_free_ctx, 124 .compress = lz4hc_scompress, 125 .decompress = lz4hc_sdecompress, 126 .base = { 127 .cra_name = "lz4hc", 128 .cra_driver_name = "lz4hc-scomp", 129 .cra_module = THIS_MODULE, 130 } 131 }; 132 133 static int __init lz4hc_mod_init(void) 134 { 135 int ret; 136 137 ret = crypto_register_alg(&alg_lz4hc); 138 if (ret) 139 return ret; 140 141 ret = crypto_register_scomp(&scomp); 142 if (ret) { 143 crypto_unregister_alg(&alg_lz4hc); 144 return ret; 145 } 146 147 return ret; 148 } 149 150 static void __exit lz4hc_mod_fini(void) 151 { 152 crypto_unregister_alg(&alg_lz4hc); 153 crypto_unregister_scomp(&scomp); 154 } 155 156 subsys_initcall(lz4hc_mod_init); 157 module_exit(lz4hc_mod_fini); 158 159 MODULE_LICENSE("GPL"); 160 MODULE_DESCRIPTION("LZ4HC Compression Algorithm"); 161 MODULE_ALIAS_CRYPTO("lz4hc"); 162