crypto/lzo.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Cryptographic API.
   4  */
   5
   6 #include <linux/init.h>
   7 #include <linux/module.h>
   8 #include <linux/crypto.h>
   9 #include <linux/vmalloc.h>
  10 #include <linux/mm.h>
  11 #include <linux/lzo.h>
  12 #include <crypto/internal/scompress.h>
  13
  14 struct lzo_ctx {
  15         void *lzo_comp_mem;
  16 };
  17
  18 static void *lzo_alloc_ctx(struct crypto_scomp *tfm)
  19 {
  20         void *ctx;
  21
  22         ctx = kvmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
  23         if (!ctx)
  24                 return ERR_PTR(-ENOMEM);
  25
  26         return ctx;
  27 }
  28
  29 static int lzo_init(struct crypto_tfm *tfm)
  30 {
  31         struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
  32
  33         ctx->lzo_comp_mem = lzo_alloc_ctx(NULL);
  34         if (IS_ERR(ctx->lzo_comp_mem))
  35                 return -ENOMEM;
  36
  37         return 0;
  38 }
  39
  40 static void lzo_free_ctx(struct crypto_scomp *tfm, void *ctx)
  41 {
  42         kvfree(ctx);
  43 }
  44
  45 static void lzo_exit(struct crypto_tfm *tfm)
  46 {
  47         struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
  48
  49         lzo_free_ctx(NULL, ctx->lzo_comp_mem);
  50 }
  51
  52 static int __lzo_compress(const u8 *src, unsigned int slen,
  53                           u8 *dst, unsigned int *dlen, void *ctx)
  54 {
  55         size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
  56         int err;
  57
  58         err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx);
  59
  60         if (err != LZO_E_OK)
  61                 return -EINVAL;
  62
  63         *dlen = tmp_len;
  64         return 0;
  65 }
  66
  67 static int lzo_compress(struct crypto_tfm *tfm, const u8 *src,
  68                         unsigned int slen, u8 *dst, unsigned int *dlen)
  69 {
  70         struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
  71
  72         return __lzo_compress(src, slen, dst, dlen, ctx->lzo_comp_mem);
  73 }
  74
  75 static int lzo_scompress(struct crypto_scomp *tfm, const u8 *src,
  76                          unsigned int slen, u8 *dst, unsigned int *dlen,
  77                          void *ctx)
  78 {
  79         return __lzo_compress(src, slen, dst, dlen, ctx);
  80 }
  81
  82 static int __lzo_decompress(const u8 *src, unsigned int slen,
  83                             u8 *dst, unsigned int *dlen)
  84 {
  85         int err;
  86         size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
  87
  88         err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);
  89
  90         if (err != LZO_E_OK)
  91                 return -EINVAL;
  92
  93         *dlen = tmp_len;
  94         return 0;
  95 }
  96
  97 static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src,
  98                           unsigned int slen, u8 *dst, unsigned int *dlen)
  99 {
 100         return __lzo_decompress(src, slen, dst, dlen);
 101 }
 102
 103 static int lzo_sdecompress(struct crypto_scomp *tfm, const u8 *src,
 104                            unsigned int slen, u8 *dst, unsigned int *dlen,
 105                            void *ctx)
 106 {
 107         return __lzo_decompress(src, slen, dst, dlen);
 108 }
 109
 110 static struct crypto_alg alg = {
 111         .cra_name               = "lzo",
 112         .cra_driver_name        = "lzo-generic",
 113         .cra_flags              = CRYPTO_ALG_TYPE_COMPRESS,
 114         .cra_ctxsize            = sizeof(struct lzo_ctx),
 115         .cra_module             = THIS_MODULE,
 116         .cra_init               = lzo_init,
 117         .cra_exit               = lzo_exit,
 118         .cra_u                  = { .compress = {
 119         .coa_compress           = lzo_compress,
 120         .coa_decompress         = lzo_decompress } }
 121 };
 122
 123 static struct scomp_alg scomp = {
 124         .alloc_ctx              = lzo_alloc_ctx,
 125         .free_ctx               = lzo_free_ctx,
 126         .compress               = lzo_scompress,
 127         .decompress             = lzo_sdecompress,
 128         .base                   = {
 129                 .cra_name       = "lzo",
 130                 .cra_driver_name = "lzo-scomp",
 131                 .cra_module      = THIS_MODULE,
 132         }
 133 };
 134
 135 static int __init lzo_mod_init(void)
 136 {
 137         int ret;
 138
 139         ret = crypto_register_alg(&alg);
 140         if (ret)
 141                 return ret;
 142
 143         ret = crypto_register_scomp(&scomp);
 144         if (ret) {
 145                 crypto_unregister_alg(&alg);
 146                 return ret;
 147         }
 148
 149         return ret;
 150 }
 151
 152 static void __exit lzo_mod_fini(void)
 153 {
 154         crypto_unregister_alg(&alg);
 155         crypto_unregister_scomp(&scomp);
 156 }
 157
 158 subsys_initcall(lzo_mod_init);
 159 module_exit(lzo_mod_fini);
 160
 161 MODULE_LICENSE("GPL");
 162 MODULE_DESCRIPTION("LZO Compression Algorithm");
 163 MODULE_ALIAS_CRYPTO("lzo");