crypto/lz4hc.c

   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");