1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Cryptographic API. 4 * 5 * Copyright (c) 2017-present, Facebook, Inc. 6 */ 7 #include <linux/crypto.h> 8 #include <linux/init.h> 9 #include <linux/interrupt.h> 10 #include <linux/mm.h> 11 #include <linux/module.h> 12 #include <linux/net.h> 13 #include <linux/vmalloc.h> 14 #include <linux/zstd.h> 15 #include <crypto/internal/scompress.h> 16 17 18 #define ZSTD_DEF_LEVEL 3 19 20 struct zstd_ctx { 21 ZSTD_CCtx *cctx; 22 ZSTD_DCtx *dctx; 23 void *cwksp; 24 void *dwksp; 25 }; 26 27 static ZSTD_parameters zstd_params(void) 28 { 29 return ZSTD_getParams(ZSTD_DEF_LEVEL, 0, 0); 30 } 31 32 static int zstd_comp_init(struct zstd_ctx *ctx) 33 { 34 int ret = 0; 35 const ZSTD_parameters params = zstd_params(); 36 const size_t wksp_size = ZSTD_CCtxWorkspaceBound(params.cParams); 37 38 ctx->cwksp = vzalloc(wksp_size); 39 if (!ctx->cwksp) { 40 ret = -ENOMEM; 41 goto out; 42 } 43 44 ctx->cctx = ZSTD_initCCtx(ctx->cwksp, wksp_size); 45 if (!ctx->cctx) { 46 ret = -EINVAL; 47 goto out_free; 48 } 49 out: 50 return ret; 51 out_free: 52 vfree(ctx->cwksp); 53 goto out; 54 } 55 56 static int zstd_decomp_init(struct zstd_ctx *ctx) 57 { 58 int ret = 0; 59 const size_t wksp_size = ZSTD_DCtxWorkspaceBound(); 60 61 ctx->dwksp = vzalloc(wksp_size); 62 if (!ctx->dwksp) { 63 ret = -ENOMEM; 64 goto out; 65 } 66 67 ctx->dctx = ZSTD_initDCtx(ctx->dwksp, wksp_size); 68 if (!ctx->dctx) { 69 ret = -EINVAL; 70 goto out_free; 71 } 72 out: 73 return ret; 74 out_free: 75 vfree(ctx->dwksp); 76 goto out; 77 } 78 79 static void zstd_comp_exit(struct zstd_ctx *ctx) 80 { 81 vfree(ctx->cwksp); 82 ctx->cwksp = NULL; 83 ctx->cctx = NULL; 84 } 85 86 static void zstd_decomp_exit(struct zstd_ctx *ctx) 87 { 88 vfree(ctx->dwksp); 89 ctx->dwksp = NULL; 90 ctx->dctx = NULL; 91 } 92 93 static int __zstd_init(void *ctx) 94 { 95 int ret; 96 97 ret = zstd_comp_init(ctx); 98 if (ret) 99 return ret; 100 ret = zstd_decomp_init(ctx); 101 if (ret) 102 zstd_comp_exit(ctx); 103 return ret; 104 } 105 106 static void *zstd_alloc_ctx(struct crypto_scomp *tfm) 107 { 108 int ret; 109 struct zstd_ctx *ctx; 110 111 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); 112 if (!ctx) 113 return ERR_PTR(-ENOMEM); 114 115 ret = __zstd_init(ctx); 116 if (ret) { 117 kfree(ctx); 118 return ERR_PTR(ret); 119 } 120 121 return ctx; 122 } 123 124 static int zstd_init(struct crypto_tfm *tfm) 125 { 126 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); 127 128 return __zstd_init(ctx); 129 } 130 131 static void __zstd_exit(void *ctx) 132 { 133 zstd_comp_exit(ctx); 134 zstd_decomp_exit(ctx); 135 } 136 137 static void zstd_free_ctx(struct crypto_scomp *tfm, void *ctx) 138 { 139 __zstd_exit(ctx); 140 kfree_sensitive(ctx); 141 } 142 143 static void zstd_exit(struct crypto_tfm *tfm) 144 { 145 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); 146 147 __zstd_exit(ctx); 148 } 149 150 static int __zstd_compress(const u8 *src, unsigned int slen, 151 u8 *dst, unsigned int *dlen, void *ctx) 152 { 153 size_t out_len; 154 struct zstd_ctx *zctx = ctx; 155 const ZSTD_parameters params = zstd_params(); 156 157 out_len = ZSTD_compressCCtx(zctx->cctx, dst, *dlen, src, slen, params); 158 if (ZSTD_isError(out_len)) 159 return -EINVAL; 160 *dlen = out_len; 161 return 0; 162 } 163 164 static int zstd_compress(struct crypto_tfm *tfm, const u8 *src, 165 unsigned int slen, u8 *dst, unsigned int *dlen) 166 { 167 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); 168 169 return __zstd_compress(src, slen, dst, dlen, ctx); 170 } 171 172 static int zstd_scompress(struct crypto_scomp *tfm, const u8 *src, 173 unsigned int slen, u8 *dst, unsigned int *dlen, 174 void *ctx) 175 { 176 return __zstd_compress(src, slen, dst, dlen, ctx); 177 } 178 179 static int __zstd_decompress(const u8 *src, unsigned int slen, 180 u8 *dst, unsigned int *dlen, void *ctx) 181 { 182 size_t out_len; 183 struct zstd_ctx *zctx = ctx; 184 185 out_len = ZSTD_decompressDCtx(zctx->dctx, dst, *dlen, src, slen); 186 if (ZSTD_isError(out_len)) 187 return -EINVAL; 188 *dlen = out_len; 189 return 0; 190 } 191 192 static int zstd_decompress(struct crypto_tfm *tfm, const u8 *src, 193 unsigned int slen, u8 *dst, unsigned int *dlen) 194 { 195 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm); 196 197 return __zstd_decompress(src, slen, dst, dlen, ctx); 198 } 199 200 static int zstd_sdecompress(struct crypto_scomp *tfm, const u8 *src, 201 unsigned int slen, u8 *dst, unsigned int *dlen, 202 void *ctx) 203 { 204 return __zstd_decompress(src, slen, dst, dlen, ctx); 205 } 206 207 static struct crypto_alg alg = { 208 .cra_name = "zstd", 209 .cra_driver_name = "zstd-generic", 210 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, 211 .cra_ctxsize = sizeof(struct zstd_ctx), 212 .cra_module = THIS_MODULE, 213 .cra_init = zstd_init, 214 .cra_exit = zstd_exit, 215 .cra_u = { .compress = { 216 .coa_compress = zstd_compress, 217 .coa_decompress = zstd_decompress } } 218 }; 219 220 static struct scomp_alg scomp = { 221 .alloc_ctx = zstd_alloc_ctx, 222 .free_ctx = zstd_free_ctx, 223 .compress = zstd_scompress, 224 .decompress = zstd_sdecompress, 225 .base = { 226 .cra_name = "zstd", 227 .cra_driver_name = "zstd-scomp", 228 .cra_module = THIS_MODULE, 229 } 230 }; 231 232 static int __init zstd_mod_init(void) 233 { 234 int ret; 235 236 ret = crypto_register_alg(&alg); 237 if (ret) 238 return ret; 239 240 ret = crypto_register_scomp(&scomp); 241 if (ret) 242 crypto_unregister_alg(&alg); 243 244 return ret; 245 } 246 247 static void __exit zstd_mod_fini(void) 248 { 249 crypto_unregister_alg(&alg); 250 crypto_unregister_scomp(&scomp); 251 } 252 253 subsys_initcall(zstd_mod_init); 254 module_exit(zstd_mod_fini); 255 256 MODULE_LICENSE("GPL"); 257 MODULE_DESCRIPTION("Zstd Compression Algorithm"); 258 MODULE_ALIAS_CRYPTO("zstd"); 259