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_get_params(ZSTD_DEF_LEVEL, 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_cctx_workspace_bound(¶ms.cParams); 37 38 ctx->cwksp = vzalloc(wksp_size); 39 if (!ctx->cwksp) { 40 ret = -ENOMEM; 41 goto out; 42 } 43 44 ctx->cctx = zstd_init_cctx(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_dctx_workspace_bound(); 60 61 ctx->dwksp = vzalloc(wksp_size); 62 if (!ctx->dwksp) { 63 ret = -ENOMEM; 64 goto out; 65 } 66 67 ctx->dctx = zstd_init_dctx(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(void) 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 void __zstd_exit(void *ctx) 125 { 126 zstd_comp_exit(ctx); 127 zstd_decomp_exit(ctx); 128 } 129 130 static void zstd_free_ctx(void *ctx) 131 { 132 __zstd_exit(ctx); 133 kfree_sensitive(ctx); 134 } 135 136 static int __zstd_compress(const u8 *src, unsigned int slen, 137 u8 *dst, unsigned int *dlen, void *ctx) 138 { 139 size_t out_len; 140 struct zstd_ctx *zctx = ctx; 141 const zstd_parameters params = zstd_params(); 142 143 out_len = zstd_compress_cctx(zctx->cctx, dst, *dlen, src, slen, ¶ms); 144 if (zstd_is_error(out_len)) 145 return -EINVAL; 146 *dlen = out_len; 147 return 0; 148 } 149 150 static int zstd_scompress(struct crypto_scomp *tfm, const u8 *src, 151 unsigned int slen, u8 *dst, unsigned int *dlen, 152 void *ctx) 153 { 154 return __zstd_compress(src, slen, dst, dlen, ctx); 155 } 156 157 static int __zstd_decompress(const u8 *src, unsigned int slen, 158 u8 *dst, unsigned int *dlen, void *ctx) 159 { 160 size_t out_len; 161 struct zstd_ctx *zctx = ctx; 162 163 out_len = zstd_decompress_dctx(zctx->dctx, dst, *dlen, src, slen); 164 if (zstd_is_error(out_len)) 165 return -EINVAL; 166 *dlen = out_len; 167 return 0; 168 } 169 170 static int zstd_sdecompress(struct crypto_scomp *tfm, const u8 *src, 171 unsigned int slen, u8 *dst, unsigned int *dlen, 172 void *ctx) 173 { 174 return __zstd_decompress(src, slen, dst, dlen, ctx); 175 } 176 177 static struct scomp_alg scomp = { 178 .alloc_ctx = zstd_alloc_ctx, 179 .free_ctx = zstd_free_ctx, 180 .compress = zstd_scompress, 181 .decompress = zstd_sdecompress, 182 .base = { 183 .cra_name = "zstd", 184 .cra_driver_name = "zstd-scomp", 185 .cra_module = THIS_MODULE, 186 } 187 }; 188 189 static int __init zstd_mod_init(void) 190 { 191 return crypto_register_scomp(&scomp); 192 } 193 194 static void __exit zstd_mod_fini(void) 195 { 196 crypto_unregister_scomp(&scomp); 197 } 198 199 subsys_initcall(zstd_mod_init); 200 module_exit(zstd_mod_fini); 201 202 MODULE_LICENSE("GPL"); 203 MODULE_DESCRIPTION("Zstd Compression Algorithm"); 204 MODULE_ALIAS_CRYPTO("zstd"); 205