// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   * Public Key Encryption
   *
   * Copyright (c) 2015, Intel Corporation
   * Authors: Tadeusz Struk <tadeusz.struk@intel.com>

   */
  #include <linux/errno.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/seq_file.h>
  #include <linux/slab.h>
  #include <linux/string.h>
  #include <linux/crypto.h>

  #include <linux/compiler.h>

  #include <crypto/algapi.h>
  #include <linux/cryptouser.h>
  #include <net/netlink.h>
  #include <crypto/akcipher.h>

  #include <crypto/internal/akcipher.h>

  #include "internal.h"
  
  #ifdef CONFIG_NET
  static int crypto_akcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
  {
  	struct crypto_report_akcipher rakcipher;

  	memset(&rakcipher, 0, sizeof(rakcipher));

  	strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));

  	return nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER,
  		       sizeof(rakcipher), &rakcipher);

  }
  #else
  static int crypto_akcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
  {
  	return -ENOSYS;
  }
  #endif
  
  static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)

  	__maybe_unused;

  
  static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
  {
  	seq_puts(m, "type         : akcipher
  ");
  }
  
  static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
  {
  	struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
  	struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
  
  	alg->exit(akcipher);
  }
  
  static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
  {
  	struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
  	struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
  
  	if (alg->exit)
  		akcipher->base.exit = crypto_akcipher_exit_tfm;
  
  	if (alg->init)
  		return alg->init(akcipher);
  
  	return 0;
  }

  static void crypto_akcipher_free_instance(struct crypto_instance *inst)
  {
  	struct akcipher_instance *akcipher = akcipher_instance(inst);
  
  	akcipher->free(akcipher);
  }

  static const struct crypto_type crypto_akcipher_type = {
  	.extsize = crypto_alg_extsize,
  	.init_tfm = crypto_akcipher_init_tfm,

  	.free = crypto_akcipher_free_instance,

  #ifdef CONFIG_PROC_FS
  	.show = crypto_akcipher_show,
  #endif
  	.report = crypto_akcipher_report,
  	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
  	.maskset = CRYPTO_ALG_TYPE_MASK,
  	.type = CRYPTO_ALG_TYPE_AKCIPHER,
  	.tfmsize = offsetof(struct crypto_akcipher, base),
  };

  int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn,
  			 struct crypto_instance *inst,
  			 const char *name, u32 type, u32 mask)

  {
  	spawn->base.frontend = &crypto_akcipher_type;

  	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);

  }
  EXPORT_SYMBOL_GPL(crypto_grab_akcipher);

  struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
  					      u32 mask)
  {
  	return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask);
  }
  EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);

  static void akcipher_prepare_alg(struct akcipher_alg *alg)

  {
  	struct crypto_alg *base = &alg->base;
  
  	base->cra_type = &crypto_akcipher_type;
  	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
  	base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;

  }

  static int akcipher_default_op(struct akcipher_request *req)
  {
  	return -ENOSYS;
  }

  int crypto_register_akcipher(struct akcipher_alg *alg)
  {
  	struct crypto_alg *base = &alg->base;

  	if (!alg->sign)
  		alg->sign = akcipher_default_op;
  	if (!alg->verify)
  		alg->verify = akcipher_default_op;
  	if (!alg->encrypt)
  		alg->encrypt = akcipher_default_op;
  	if (!alg->decrypt)
  		alg->decrypt = akcipher_default_op;

  	akcipher_prepare_alg(alg);

  	return crypto_register_alg(base);
  }
  EXPORT_SYMBOL_GPL(crypto_register_akcipher);
  
  void crypto_unregister_akcipher(struct akcipher_alg *alg)
  {
  	crypto_unregister_alg(&alg->base);
  }
  EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);

  int akcipher_register_instance(struct crypto_template *tmpl,
  			       struct akcipher_instance *inst)
  {

  	if (WARN_ON(!inst->free))
  		return -EINVAL;

  	akcipher_prepare_alg(&inst->alg);
  	return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
  }
  EXPORT_SYMBOL_GPL(akcipher_register_instance);

  MODULE_LICENSE("GPL");

  MODULE_DESCRIPTION("Generic public key cipher type");