text: /*
   * Public Key Encryption
   *
   * Copyright (c) 2015, Intel Corporation
   * Authors: Tadeusz Struk <tadeusz.struk@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.
   *
   */
  #ifndef _CRYPTO_AKCIPHER_H
  #define _CRYPTO_AKCIPHER_H
  #include <linux/crypto.h>
  
  /**
   * struct akcipher_request - public key request
   *
   * @base:	Common attributes for async crypto requests
   * @src:	Source data
   * @dst:	Destination data
   * @src_len:	Size of the input buffer
   * @dst_len:	Size of the output buffer. It needs to be at least
   *		as big as the expected result depending	on the operation
   *		After operation it will be updated with the actual size of the
   *		result.
   *		In case of error where the dst sgl size was insufficient,
   *		it will be updated to the size required for the operation.
   * @__ctx:	Start of private context data
   */
  struct akcipher_request {
  	struct crypto_async_request base;
  	struct scatterlist *src;
  	struct scatterlist *dst;
  	unsigned int src_len;
  	unsigned int dst_len;
  	void *__ctx[] CRYPTO_MINALIGN_ATTR;
  };
  
  /**
   * struct crypto_akcipher - user-instantiated objects which encapsulate
   * algorithms and core processing logic
   *
   * @base:	Common crypto API algorithm data structure
   */
  struct crypto_akcipher {
  	struct crypto_tfm base;
  };
  
  /**
   * struct akcipher_alg - generic public key algorithm
   *
   * @sign:	Function performs a sign operation as defined by public key
   *		algorithm. In case of error, where the dst_len was insufficient,
   *		the req->dst_len will be updated to the size required for the
   *		operation
   * @verify:	Function performs a sign operation as defined by public key
   *		algorithm. In case of error, where the dst_len was insufficient,
   *		the req->dst_len will be updated to the size required for the
   *		operation
   * @encrypt:	Function performs an encrypt operation as defined by public key
   *		algorithm. In case of error, where the dst_len was insufficient,
   *		the req->dst_len will be updated to the size required for the
   *		operation
   * @decrypt:	Function performs a decrypt operation as defined by public key
   *		algorithm. In case of error, where the dst_len was insufficient,
   *		the req->dst_len will be updated to the size required for the
   *		operation
   * @set_pub_key: Function invokes the algorithm specific set public key
   *		function, which knows how to decode and interpret
   *		the BER encoded public key
   * @set_priv_key: Function invokes the algorithm specific set private key
   *		function, which knows how to decode and interpret
   *		the BER encoded private key
   * @max_size:	Function returns dest buffer size required for a given key.
   * @init:	Initialize the cryptographic transformation object.
   *		This function is used to initialize the cryptographic
   *		transformation object. This function is called only once at
   *		the instantiation time, right after the transformation context
   *		was allocated. In case the cryptographic hardware has some
   *		special requirements which need to be handled by software, this
   *		function shall check for the precise requirement of the
   *		transformation and put any software fallbacks in place.
   * @exit:	Deinitialize the cryptographic transformation object. This is a
   *		counterpart to @init, used to remove various changes set in
   *		@init.
   *
   * @reqsize:	Request context size required by algorithm implementation
   * @base:	Common crypto API algorithm data structure
   */
  struct akcipher_alg {
  	int (*sign)(struct akcipher_request *req);
  	int (*verify)(struct akcipher_request *req);
  	int (*encrypt)(struct akcipher_request *req);
  	int (*decrypt)(struct akcipher_request *req);
  	int (*set_pub_key)(struct crypto_akcipher *tfm, const void *key,
  			   unsigned int keylen);
  	int (*set_priv_key)(struct crypto_akcipher *tfm, const void *key,
  			    unsigned int keylen);
  	int (*max_size)(struct crypto_akcipher *tfm);
  	int (*init)(struct crypto_akcipher *tfm);
  	void (*exit)(struct crypto_akcipher *tfm);
  
  	unsigned int reqsize;
  	struct crypto_alg base;
  };
  
  /**
   * DOC: Generic Public Key API
   *
   * The Public Key API is used with the algorithms of type
   * CRYPTO_ALG_TYPE_AKCIPHER (listed as type "akcipher" in /proc/crypto)
   */
  
  /**
   * crypto_alloc_akcipher() -- allocate AKCIPHER tfm handle
   * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
   *	      public key algorithm e.g. "rsa"
   * @type: specifies the type of the algorithm
   * @mask: specifies the mask for the algorithm
   *
   * Allocate a handle for public key algorithm. The returned struct
   * crypto_akcipher is the handle that is required for any subsequent
   * API invocation for the public key operations.
   *
   * Return: allocated handle in case of success; IS_ERR() is true in case
   *	   of an error, PTR_ERR() returns the error code.
   */
  struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
  					      u32 mask);
  
  static inline struct crypto_tfm *crypto_akcipher_tfm(
  	struct crypto_akcipher *tfm)
  {
  	return &tfm->base;
  }
  
  static inline struct akcipher_alg *__crypto_akcipher_alg(struct crypto_alg *alg)
  {
  	return container_of(alg, struct akcipher_alg, base);
  }
  
  static inline struct crypto_akcipher *__crypto_akcipher_tfm(
  	struct crypto_tfm *tfm)
  {
  	return container_of(tfm, struct crypto_akcipher, base);
  }
  
  static inline struct akcipher_alg *crypto_akcipher_alg(
  	struct crypto_akcipher *tfm)
  {
  	return __crypto_akcipher_alg(crypto_akcipher_tfm(tfm)->__crt_alg);
  }
  
  static inline unsigned int crypto_akcipher_reqsize(struct crypto_akcipher *tfm)
  {
  	return crypto_akcipher_alg(tfm)->reqsize;
  }
  
  static inline void akcipher_request_set_tfm(struct akcipher_request *req,
  					    struct crypto_akcipher *tfm)
  {
  	req->base.tfm = crypto_akcipher_tfm(tfm);
  }
  
  static inline struct crypto_akcipher *crypto_akcipher_reqtfm(
  	struct akcipher_request *req)
  {
  	return __crypto_akcipher_tfm(req->base.tfm);
  }
  
  /**
   * crypto_free_akcipher() -- free AKCIPHER tfm handle
   *
   * @tfm: AKCIPHER tfm handle allocated with crypto_alloc_akcipher()
   */
  static inline void crypto_free_akcipher(struct crypto_akcipher *tfm)
  {
  	crypto_destroy_tfm(tfm, crypto_akcipher_tfm(tfm));
  }
  
  /**
   * akcipher_request_alloc() -- allocates public key request
   *
   * @tfm:	AKCIPHER tfm handle allocated with crypto_alloc_akcipher()
   * @gfp:	allocation flags
   *
   * Return: allocated handle in case of success or NULL in case of an error.
   */
  static inline struct akcipher_request *akcipher_request_alloc(
  	struct crypto_akcipher *tfm, gfp_t gfp)
  {
  	struct akcipher_request *req;
  
  	req = kmalloc(sizeof(*req) + crypto_akcipher_reqsize(tfm), gfp);
  	if (likely(req))
  		akcipher_request_set_tfm(req, tfm);
  
  	return req;
  }
  
  /**
   * akcipher_request_free() -- zeroize and free public key request
   *
   * @req:	request to free
   */
  static inline void akcipher_request_free(struct akcipher_request *req)
  {
  	kzfree(req);
  }
  
  /**
   * akcipher_request_set_callback() -- Sets an asynchronous callback.
   *
   * Callback will be called when an asynchronous operation on a given
   * request is finished.
   *
   * @req:	request that the callback will be set for
   * @flgs:	specify for instance if the operation may backlog
   * @cmlp:	callback which will be called
   * @data:	private data used by the caller
   */
  static inline void akcipher_request_set_callback(struct akcipher_request *req,
  						 u32 flgs,
  						 crypto_completion_t cmpl,
  						 void *data)
  {
  	req->base.complete = cmpl;
  	req->base.data = data;
  	req->base.flags = flgs;
  }
  
  /**
   * akcipher_request_set_crypt() -- Sets request parameters
   *
   * Sets parameters required by crypto operation
   *
   * @req:	public key request
   * @src:	ptr to input scatter list
   * @dst:	ptr to output scatter list
   * @src_len:	size of the src input scatter list to be processed
   * @dst_len:	size of the dst output scatter list
   */
  static inline void akcipher_request_set_crypt(struct akcipher_request *req,
  					      struct scatterlist *src,
  					      struct scatterlist *dst,
  					      unsigned int src_len,
  					      unsigned int dst_len)
  {
  	req->src = src;
  	req->dst = dst;
  	req->src_len = src_len;
  	req->dst_len = dst_len;
  }
  
  /**
   * crypto_akcipher_maxsize() -- Get len for output buffer
   *
   * Function returns the dest buffer size required for a given key
   *
   * @tfm:	AKCIPHER tfm handle allocated with crypto_alloc_akcipher()
   *
   * Return: minimum len for output buffer or error code in key hasn't been set
   */
  static inline int crypto_akcipher_maxsize(struct crypto_akcipher *tfm)
  {
  	struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
  
  	return alg->max_size(tfm);
  }
  
  /**
   * crypto_akcipher_encrypt() -- Invoke public key encrypt operation
   *
   * Function invokes the specific public key encrypt operation for a given
   * public key algorithm
   *
   * @req:	asymmetric key request
   *
   * Return: zero on success; error code in case of error
   */
  static inline int crypto_akcipher_encrypt(struct akcipher_request *req)
  {
  	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
  	struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
  
  	return alg->encrypt(req);
  }
  
  /**
   * crypto_akcipher_decrypt() -- Invoke public key decrypt operation
   *
   * Function invokes the specific public key decrypt operation for a given
   * public key algorithm
   *
   * @req:	asymmetric key request
   *
   * Return: zero on success; error code in case of error
   */
  static inline int crypto_akcipher_decrypt(struct akcipher_request *req)
  {
  	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
  	struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
  
  	return alg->decrypt(req);
  }
  
  /**
   * crypto_akcipher_sign() -- Invoke public key sign operation
   *
   * Function invokes the specific public key sign operation for a given
   * public key algorithm
   *
   * @req:	asymmetric key request
   *
   * Return: zero on success; error code in case of error
   */
  static inline int crypto_akcipher_sign(struct akcipher_request *req)
  {
  	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
  	struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
  
  	return alg->sign(req);
  }
  
  /**
   * crypto_akcipher_verify() -- Invoke public key verify operation
   *
   * Function invokes the specific public key verify operation for a given
   * public key algorithm
   *
   * @req:	asymmetric key request
   *
   * Return: zero on success; error code in case of error
   */
  static inline int crypto_akcipher_verify(struct akcipher_request *req)
  {
  	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
  	struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
  
  	return alg->verify(req);
  }
  
  /**
   * crypto_akcipher_set_pub_key() -- Invoke set public key operation
   *
   * Function invokes the algorithm specific set key function, which knows
   * how to decode and interpret the encoded key
   *
   * @tfm:	tfm handle
   * @key:	BER encoded public key
   * @keylen:	length of the key
   *
   * Return: zero on success; error code in case of error
   */
  static inline int crypto_akcipher_set_pub_key(struct crypto_akcipher *tfm,
  					      const void *key,
  					      unsigned int keylen)
  {
  	struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
  
  	return alg->set_pub_key(tfm, key, keylen);
  }
  
  /**
   * crypto_akcipher_set_priv_key() -- Invoke set private key operation
   *
   * Function invokes the algorithm specific set key function, which knows
   * how to decode and interpret the encoded key
   *
   * @tfm:	tfm handle
   * @key:	BER encoded private key
   * @keylen:	length of the key
   *
   * Return: zero on success; error code in case of error
   */
  static inline int crypto_akcipher_set_priv_key(struct crypto_akcipher *tfm,
  					       const void *key,
  					       unsigned int keylen)
  {
  	struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
  
  	return alg->set_priv_key(tfm, key, keylen);
  }
  #endif
  