diff options
Diffstat (limited to 'arch/x86/crypto/fpu.c')
| -rw-r--r-- | arch/x86/crypto/fpu.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/x86/crypto/fpu.c b/arch/x86/crypto/fpu.c new file mode 100644 index 000000000000..daef6cd2b45d --- /dev/null +++ b/arch/x86/crypto/fpu.c @@ -0,0 +1,166 @@ +/* + * FPU: Wrapper for blkcipher touching fpu + * + * Copyright (c) Intel Corp. + * Author: Huang Ying <ying.huang@intel.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include <crypto/algapi.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <asm/i387.h> + +struct crypto_fpu_ctx { + struct crypto_blkcipher *child; +}; + +static int crypto_fpu_setkey(struct crypto_tfm *parent, const u8 *key, + unsigned int keylen) +{ + struct crypto_fpu_ctx *ctx = crypto_tfm_ctx(parent); + struct crypto_blkcipher *child = ctx->child; + int err; + + crypto_blkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_blkcipher_set_flags(child, crypto_tfm_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_blkcipher_setkey(child, key, keylen); + crypto_tfm_set_flags(parent, crypto_blkcipher_get_flags(child) & + CRYPTO_TFM_RES_MASK); + return err; +} + +static int crypto_fpu_encrypt(struct blkcipher_desc *desc_in, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + int err; + struct crypto_fpu_ctx *ctx = crypto_blkcipher_ctx(desc_in->tfm); + struct crypto_blkcipher *child = ctx->child; + struct blkcipher_desc desc = { + .tfm = child, + .info = desc_in->info, + .flags = desc_in->flags & ~CRYPTO_TFM_REQ_MAY_SLEEP, + }; + + kernel_fpu_begin(); + err = crypto_blkcipher_crt(desc.tfm)->encrypt(&desc, dst, src, nbytes); + kernel_fpu_end(); + return err; +} + +static int crypto_fpu_decrypt(struct blkcipher_desc *desc_in, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + int err; + struct crypto_fpu_ctx *ctx = crypto_blkcipher_ctx(desc_in->tfm); + struct crypto_blkcipher *child = ctx->child; + struct blkcipher_desc desc = { + .tfm = child, + .info = desc_in->info, + .flags = desc_in->flags & ~CRYPTO_TFM_REQ_MAY_SLEEP, + }; + + kernel_fpu_begin(); + err = crypto_blkcipher_crt(desc.tfm)->decrypt(&desc, dst, src, nbytes); + kernel_fpu_end(); + return err; +} + +static int crypto_fpu_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = crypto_tfm_alg_instance(tfm); + struct crypto_spawn *spawn = crypto_instance_ctx(inst); + struct crypto_fpu_ctx *ctx = crypto_tfm_ctx(tfm); + struct crypto_blkcipher *cipher; + + cipher = crypto_spawn_blkcipher(spawn); + if (IS_ERR(cipher)) + return PTR_ERR(cipher); + + ctx->child = cipher; + return 0; +} + +static void crypto_fpu_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_fpu_ctx *ctx = crypto_tfm_ctx(tfm); + crypto_free_blkcipher(ctx->child); +} + +static struct crypto_instance *crypto_fpu_alloc(struct rtattr **tb) +{ + struct crypto_instance *inst; + struct crypto_alg *alg; + int err; + + err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER); + if (err) + return ERR_PTR(err); + + alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_BLKCIPHER, + CRYPTO_ALG_TYPE_MASK); + if (IS_ERR(alg)) + return ERR_CAST(alg); + + inst = crypto_alloc_instance("fpu", alg); + if (IS_ERR(inst)) + goto out_put_alg; + + inst->alg.cra_flags = alg->cra_flags; + inst->alg.cra_priority = alg->cra_priority; + inst->alg.cra_blocksize = alg->cra_blocksize; + inst->alg.cra_alignmask = alg->cra_alignmask; + inst->alg.cra_type = alg->cra_type; + inst->alg.cra_blkcipher.ivsize = alg->cra_blkcipher.ivsize; + inst->alg.cra_blkcipher.min_keysize = alg->cra_blkcipher.min_keysize; + inst->alg.cra_blkcipher.max_keysize = alg->cra_blkcipher.max_keysize; + inst->alg.cra_ctxsize = sizeof(struct crypto_fpu_ctx); + inst->alg.cra_init = crypto_fpu_init_tfm; + inst->alg.cra_exit = crypto_fpu_exit_tfm; + inst->alg.cra_blkcipher.setkey = crypto_fpu_setkey; + inst->alg.cra_blkcipher.encrypt = crypto_fpu_encrypt; + inst->alg.cra_blkcipher.decrypt = crypto_fpu_decrypt; + +out_put_alg: + crypto_mod_put(alg); + return inst; +} + +static void crypto_fpu_free(struct crypto_instance *inst) +{ + crypto_drop_spawn(crypto_instance_ctx(inst)); + kfree(inst); +} + +static struct crypto_template crypto_fpu_tmpl = { + .name = "fpu", + .alloc = crypto_fpu_alloc, + .free = crypto_fpu_free, + .module = THIS_MODULE, +}; + +static int __init crypto_fpu_module_init(void) +{ + return crypto_register_template(&crypto_fpu_tmpl); +} + +static void __exit crypto_fpu_module_exit(void) +{ + crypto_unregister_template(&crypto_fpu_tmpl); +} + +module_init(crypto_fpu_module_init); +module_exit(crypto_fpu_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("FPU block cipher wrapper"); |