linux/arch/x86/crypto/fpu.c
<<
>>
Prefs
   1/*
   2 * FPU: Wrapper for blkcipher touching fpu
   3 *
   4 * Copyright (c) Intel Corp.
   5 *   Author: Huang Ying <ying.huang@intel.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms of the GNU General Public License as published by the Free
   9 * Software Foundation; either version 2 of the License, or (at your option)
  10 * any later version.
  11 *
  12 */
  13
  14#include <crypto/internal/skcipher.h>
  15#include <linux/err.h>
  16#include <linux/init.h>
  17#include <linux/kernel.h>
  18#include <linux/module.h>
  19#include <linux/slab.h>
  20#include <asm/fpu/api.h>
  21
  22struct crypto_fpu_ctx {
  23        struct crypto_skcipher *child;
  24};
  25
  26static int crypto_fpu_setkey(struct crypto_skcipher *parent, const u8 *key,
  27                             unsigned int keylen)
  28{
  29        struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(parent);
  30        struct crypto_skcipher *child = ctx->child;
  31        int err;
  32
  33        crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  34        crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) &
  35                                         CRYPTO_TFM_REQ_MASK);
  36        err = crypto_skcipher_setkey(child, key, keylen);
  37        crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) &
  38                                          CRYPTO_TFM_RES_MASK);
  39        return err;
  40}
  41
  42static int crypto_fpu_encrypt(struct skcipher_request *req)
  43{
  44        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  45        struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
  46        struct crypto_skcipher *child = ctx->child;
  47        SKCIPHER_REQUEST_ON_STACK(subreq, child);
  48        int err;
  49
  50        skcipher_request_set_tfm(subreq, child);
  51        skcipher_request_set_callback(subreq, 0, NULL, NULL);
  52        skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
  53                                   req->iv);
  54
  55        kernel_fpu_begin();
  56        err = crypto_skcipher_encrypt(subreq);
  57        kernel_fpu_end();
  58
  59        skcipher_request_zero(subreq);
  60        return err;
  61}
  62
  63static int crypto_fpu_decrypt(struct skcipher_request *req)
  64{
  65        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  66        struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
  67        struct crypto_skcipher *child = ctx->child;
  68        SKCIPHER_REQUEST_ON_STACK(subreq, child);
  69        int err;
  70
  71        skcipher_request_set_tfm(subreq, child);
  72        skcipher_request_set_callback(subreq, 0, NULL, NULL);
  73        skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
  74                                   req->iv);
  75
  76        kernel_fpu_begin();
  77        err = crypto_skcipher_decrypt(subreq);
  78        kernel_fpu_end();
  79
  80        skcipher_request_zero(subreq);
  81        return err;
  82}
  83
  84static int crypto_fpu_init_tfm(struct crypto_skcipher *tfm)
  85{
  86        struct skcipher_instance *inst = skcipher_alg_instance(tfm);
  87        struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
  88        struct crypto_skcipher_spawn *spawn;
  89        struct crypto_skcipher *cipher;
  90
  91        spawn = skcipher_instance_ctx(inst);
  92        cipher = crypto_spawn_skcipher(spawn);
  93        if (IS_ERR(cipher))
  94                return PTR_ERR(cipher);
  95
  96        ctx->child = cipher;
  97
  98        return 0;
  99}
 100
 101static void crypto_fpu_exit_tfm(struct crypto_skcipher *tfm)
 102{
 103        struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
 104
 105        crypto_free_skcipher(ctx->child);
 106}
 107
 108static void crypto_fpu_free(struct skcipher_instance *inst)
 109{
 110        crypto_drop_skcipher(skcipher_instance_ctx(inst));
 111        kfree(inst);
 112}
 113
 114static int crypto_fpu_create(struct crypto_template *tmpl, struct rtattr **tb)
 115{
 116        struct crypto_skcipher_spawn *spawn;
 117        struct skcipher_instance *inst;
 118        struct crypto_attr_type *algt;
 119        struct skcipher_alg *alg;
 120        const char *cipher_name;
 121        int err;
 122
 123        algt = crypto_get_attr_type(tb);
 124        if (IS_ERR(algt))
 125                return PTR_ERR(algt);
 126
 127        if ((algt->type ^ (CRYPTO_ALG_INTERNAL | CRYPTO_ALG_TYPE_SKCIPHER)) &
 128            algt->mask)
 129                return -EINVAL;
 130
 131        if (!(algt->mask & CRYPTO_ALG_INTERNAL))
 132                return -EINVAL;
 133
 134        cipher_name = crypto_attr_alg_name(tb[1]);
 135        if (IS_ERR(cipher_name))
 136                return PTR_ERR(cipher_name);
 137
 138        inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
 139        if (!inst)
 140                return -ENOMEM;
 141
 142        spawn = skcipher_instance_ctx(inst);
 143
 144        crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst));
 145        err = crypto_grab_skcipher(spawn, cipher_name, CRYPTO_ALG_INTERNAL,
 146                                   CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
 147        if (err)
 148                goto out_free_inst;
 149
 150        alg = crypto_skcipher_spawn_alg(spawn);
 151
 152        err = crypto_inst_setname(skcipher_crypto_instance(inst), "fpu",
 153                                  &alg->base);
 154        if (err)
 155                goto out_drop_skcipher;
 156
 157        inst->alg.base.cra_flags = CRYPTO_ALG_INTERNAL;
 158        inst->alg.base.cra_priority = alg->base.cra_priority;
 159        inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
 160        inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
 161
 162        inst->alg.ivsize = crypto_skcipher_alg_ivsize(alg);
 163        inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg);
 164        inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg);
 165
 166        inst->alg.base.cra_ctxsize = sizeof(struct crypto_fpu_ctx);
 167
 168        inst->alg.init = crypto_fpu_init_tfm;
 169        inst->alg.exit = crypto_fpu_exit_tfm;
 170
 171        inst->alg.setkey = crypto_fpu_setkey;
 172        inst->alg.encrypt = crypto_fpu_encrypt;
 173        inst->alg.decrypt = crypto_fpu_decrypt;
 174
 175        inst->free = crypto_fpu_free;
 176
 177        err = skcipher_register_instance(tmpl, inst);
 178        if (err)
 179                goto out_drop_skcipher;
 180
 181out:
 182        return err;
 183
 184out_drop_skcipher:
 185        crypto_drop_skcipher(spawn);
 186out_free_inst:
 187        kfree(inst);
 188        goto out;
 189}
 190
 191static struct crypto_template crypto_fpu_tmpl = {
 192        .name = "fpu",
 193        .create = crypto_fpu_create,
 194        .module = THIS_MODULE,
 195};
 196
 197int __init crypto_fpu_init(void)
 198{
 199        return crypto_register_template(&crypto_fpu_tmpl);
 200}
 201
 202void crypto_fpu_exit(void)
 203{
 204        crypto_unregister_template(&crypto_fpu_tmpl);
 205}
 206
 207MODULE_ALIAS_CRYPTO("fpu");
 208