text: /* Originally written by Bodo Moeller for the OpenSSL project.
   * ====================================================================
   * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. All advertising materials mentioning features or use of this
   *    software must display the following acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
   *
   * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
   *    endorse or promote products derived from this software without
   *    prior written permission. For written permission, please contact
   *    openssl-core@openssl.org.
   *
   * 5. Products derived from this software may not be called "OpenSSL"
   *    nor may "OpenSSL" appear in their names without prior written
   *    permission of the OpenSSL Project.
   *
   * 6. Redistributions of any form whatsoever must retain the following
   *    acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
   *
   * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
   * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
   * OF THE POSSIBILITY OF SUCH DAMAGE.
   * ====================================================================
   *
   * This product includes cryptographic software written by Eric Young
   * (eay@cryptsoft.com).  This product includes software written by Tim
   * Hudson (tjh@cryptsoft.com).
   *
   */
  /* ====================================================================
   * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
   *
   * Portions of the attached software ("Contribution") are developed by
   * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
   *
   * The Contribution is licensed pursuant to the OpenSSL open source
   * license provided above.
   *
   * The elliptic curve binary polynomial software is originally written by
   * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems
   * Laboratories. */
  
  #ifndef OPENSSL_HEADER_EC_KEY_H
  #define OPENSSL_HEADER_EC_KEY_H
  
  #include <openssl/base.h>
  
  #include <openssl/ec.h>
  #include <openssl/engine.h>
  #include <openssl/ex_data.h>
  
  #if defined(__cplusplus)
  extern "C" {
  #endif
  
  
  /* ec_key.h contains functions that handle elliptic-curve points that are
   * public/private keys. */
  
  
  /* EC key objects. */
  
  /* EC_KEY_new returns a fresh |EC_KEY| object or NULL on error. */
  OPENSSL_EXPORT EC_KEY *EC_KEY_new(void);
  
  /* EC_KEY_new_method acts the same as |EC_KEY_new|, but takes an explicit
   * |ENGINE|. */
  OPENSSL_EXPORT EC_KEY *EC_KEY_new_method(const ENGINE *engine);
  
  /* EC_KEY_new_by_curve_name returns a fresh EC_KEY for group specified by |nid|
   * or NULL on error. */
  OPENSSL_EXPORT EC_KEY *EC_KEY_new_by_curve_name(int nid);
  
  /* EC_KEY_free frees all the data owned by |key| and |key| itself. */
  OPENSSL_EXPORT void EC_KEY_free(EC_KEY *key);
  
  /* EC_KEY_copy sets |dst| equal to |src| and returns |dst| or NULL on error. */
  OPENSSL_EXPORT EC_KEY *EC_KEY_copy(EC_KEY *dst, const EC_KEY *src);
  
  /* EC_KEY_dup returns a fresh copy of |src| or NULL on error. */
  OPENSSL_EXPORT EC_KEY *EC_KEY_dup(const EC_KEY *src);
  
  /* EC_KEY_up_ref increases the reference count of |key| and returns one. */
  OPENSSL_EXPORT int EC_KEY_up_ref(EC_KEY *key);
  
  /* EC_KEY_is_opaque returns one if |key| is opaque and doesn't expose its key
   * material. Otherwise it return zero. */
  OPENSSL_EXPORT int EC_KEY_is_opaque(const EC_KEY *key);
  
  /* EC_KEY_get0_group returns a pointer to the |EC_GROUP| object inside |key|. */
  OPENSSL_EXPORT const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key);
  
  /* EC_KEY_set_group sets the |EC_GROUP| object that |key| will use to |group|.
   * It returns one on success and zero otherwise. */
  OPENSSL_EXPORT int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group);
  
  /* EC_KEY_get0_private_key returns a pointer to the private key inside |key|. */
  OPENSSL_EXPORT const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key);
  
  /* EC_KEY_set_private_key sets the private key of |key| to |priv|. It returns
   * one on success and zero otherwise. */
  OPENSSL_EXPORT int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *prv);
  
  /* EC_KEY_get0_public_key returns a pointer to the public key point inside
   * |key|. */
  OPENSSL_EXPORT const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key);
  
  /* EC_KEY_set_public_key sets the public key of |key| to |pub|, by copying it.
   * It returns one on success and zero otherwise. */
  OPENSSL_EXPORT int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub);
  
  #define EC_PKEY_NO_PARAMETERS 0x001
  #define EC_PKEY_NO_PUBKEY 0x002
  
  /* EC_KEY_get_enc_flags returns the encoding flags for |key|, which is a
   * bitwise-OR of |EC_PKEY_*| values. */
  OPENSSL_EXPORT unsigned EC_KEY_get_enc_flags(const EC_KEY *key);
  
  /* EC_KEY_set_enc_flags sets the encoding flags for |key|, which is a
   * bitwise-OR of |EC_PKEY_*| values. */
  OPENSSL_EXPORT void EC_KEY_set_enc_flags(EC_KEY *key, unsigned flags);
  
  /* EC_KEY_get_conv_form returns the conversation form that will be used by
   * |key|. */
  OPENSSL_EXPORT point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key);
  
  /* EC_KEY_set_conv_form sets the conversion form to be used by |key|. */
  OPENSSL_EXPORT void EC_KEY_set_conv_form(EC_KEY *key,
                                           point_conversion_form_t cform);
  
  /* EC_KEY_check_key performs several checks on |key| (possibly including an
   * expensive check that the public key is in the primary subgroup). It returns
   * one if all checks pass and zero otherwise. If it returns zero then detail
   * about the problem can be found on the error stack. */
  OPENSSL_EXPORT int EC_KEY_check_key(const EC_KEY *key);
  
  /* EC_KEY_set_public_key_affine_coordinates sets the public key in |key| to
   * (|x|, |y|). It returns one on success and zero otherwise. */
  OPENSSL_EXPORT int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key,
                                                              BIGNUM *x,
                                                              BIGNUM *y);
  
  
  /* Key generation. */
  
  /* EC_KEY_generate_key generates a random, private key, calculates the
   * corresponding public key and stores both in |key|. It returns one on success
   * or zero otherwise. */
  OPENSSL_EXPORT int EC_KEY_generate_key(EC_KEY *key);
  
  
  /* Serialisation. */
  
  /* EC_KEY_parse_private_key parses a DER-encoded ECPrivateKey structure (RFC
   * 5915) from |cbs| and advances |cbs|. It returns a newly-allocated |EC_KEY| or
   * NULL on error. If |group| is non-null, the parameters field of the
   * ECPrivateKey may be omitted (but must match |group| if present). Otherwise,
   * the parameters field is required. */
  OPENSSL_EXPORT EC_KEY *EC_KEY_parse_private_key(CBS *cbs,
                                                  const EC_GROUP *group);
  
  /* EC_KEY_marshal_private_key marshals |key| as a DER-encoded ECPrivateKey
   * structure (RFC 5915) and appends the result to |cbb|. It returns one on
   * success and zero on failure. |enc_flags| is a combination of |EC_PKEY_*|
   * values and controls whether corresponding fields are omitted. */
  OPENSSL_EXPORT int EC_KEY_marshal_private_key(CBB *cbb, const EC_KEY *key,
                                                unsigned enc_flags);
  
  /* EC_KEY_parse_curve_name parses a DER-encoded OBJECT IDENTIFIER as a curve
   * name from |cbs| and advances |cbs|. It returns a newly-allocated |EC_GROUP|
   * or NULL on error. */
  OPENSSL_EXPORT EC_GROUP *EC_KEY_parse_curve_name(CBS *cbs);
  
  /* EC_KEY_marshal_curve_name marshals |group| as a DER-encoded OBJECT IDENTIFIER
   * and appends the result to |cbb|. It returns one on success and zero on
   * failure. */
  OPENSSL_EXPORT int EC_KEY_marshal_curve_name(CBB *cbb, const EC_GROUP *group);
  
  /* EC_KEY_parse_parameters parses a DER-encoded ECParameters structure (RFC
   * 5480) from |cbs| and advances |cbs|. It returns a newly-allocated |EC_GROUP|
   * or NULL on error. It supports the namedCurve and specifiedCurve options, but
   * use of specifiedCurve is deprecated. Use |EC_KEY_parse_curve_name|
   * instead. */
  OPENSSL_EXPORT EC_GROUP *EC_KEY_parse_parameters(CBS *cbs);
  
  
  /* ex_data functions.
   *
   * These functions are wrappers. See |ex_data.h| for details. */
  
  OPENSSL_EXPORT int EC_KEY_get_ex_new_index(long argl, void *argp,
                                             CRYPTO_EX_unused *unused,
                                             CRYPTO_EX_dup *dup_func,
                                             CRYPTO_EX_free *free_func);
  OPENSSL_EXPORT int EC_KEY_set_ex_data(EC_KEY *r, int idx, void *arg);
  OPENSSL_EXPORT void *EC_KEY_get_ex_data(const EC_KEY *r, int idx);
  
  
  /* ECDSA method. */
  
  /* ECDSA_FLAG_OPAQUE specifies that this ECDSA_METHOD does not expose its key
   * material. This may be set if, for instance, it is wrapping some other crypto
   * API, like a platform key store. */
  #define ECDSA_FLAG_OPAQUE 1
  
  /* ecdsa_method_st is a structure of function pointers for implementing ECDSA.
   * See engine.h. */
  struct ecdsa_method_st {
    struct openssl_method_common_st common;
  
    void *app_data;
  
    int (*init)(EC_KEY *key);
    int (*finish)(EC_KEY *key);
  
    /* group_order_size returns the number of bytes needed to represent the order
     * of the group. This is used to calculate the maximum size of an ECDSA
     * signature in |ECDSA_size|. */
    size_t (*group_order_size)(const EC_KEY *key);
  
    /* sign matches the arguments and behaviour of |ECDSA_sign|. */
    int (*sign)(const uint8_t *digest, size_t digest_len, uint8_t *sig,
                unsigned int *sig_len, EC_KEY *eckey);
  
    /* Ignored. Set this to NULL. */
    int (*verify)(const uint8_t *digest, size_t digest_len, const uint8_t *sig,
                  size_t sig_len, EC_KEY *eckey);
  
    int flags;
  };
  
  
  /* Deprecated functions. */
  
  /* EC_KEY_set_asn1_flag does nothing. */
  OPENSSL_EXPORT void EC_KEY_set_asn1_flag(EC_KEY *key, int flag);
  
  /* d2i_ECPrivateKey parses an ASN.1, DER-encoded, private key from |len| bytes
   * at |*inp|. If |out_key| is not NULL then, on exit, a pointer to the result
   * is in |*out_key|. Note that, even if |*out_key| is already non-NULL on entry,
   * it * will not be written to. Rather, a fresh |EC_KEY| is allocated and the
   * previous * one is freed. On successful exit, |*inp| is advanced past the DER
   * structure. It returns the result or NULL on error.
   *
   * On input, if |*out_key| is non-NULL and has a group configured, the
   * parameters field may be omitted but must match that group if present.
   *
   * Use |EC_KEY_parse_private_key| instead. */
  OPENSSL_EXPORT EC_KEY *d2i_ECPrivateKey(EC_KEY **out_key, const uint8_t **inp,
                                          long len);
  
  /* i2d_ECPrivateKey marshals an EC private key from |key| to an ASN.1, DER
   * structure. If |outp| is not NULL then the result is written to |*outp| and
   * |*outp| is advanced just past the output. It returns the number of bytes in
   * the result, whether written or not, or a negative value on error.
   *
   * Use |EC_KEY_marshal_private_key| instead. */
  OPENSSL_EXPORT int i2d_ECPrivateKey(const EC_KEY *key, uint8_t **outp);
  
  /* d2i_ECParameters parses an ASN.1, DER-encoded, set of EC parameters from
   * |len| bytes at |*inp|. If |out_key| is not NULL then, on exit, a pointer to
   * the result is in |*out_key|. Note that, even if |*out_key| is already
   * non-NULL on entry, it will not be written to. Rather, a fresh |EC_KEY| is
   * allocated and the previous one is freed. On successful exit, |*inp| is
   * advanced past the DER structure. It returns the result or NULL on error.
   *
   * Use |EC_KEY_parse_parameters| or |EC_KEY_parse_curve_name| instead. */
  OPENSSL_EXPORT EC_KEY *d2i_ECParameters(EC_KEY **out_key, const uint8_t **inp,
                                          long len);
  
  /* i2d_ECParameters marshals EC parameters from |key| to an ASN.1, DER
   * structure. If |outp| is not NULL then the result is written to |*outp| and
   * |*outp| is advanced just past the output. It returns the number of bytes in
   * the result, whether written or not, or a negative value on error.
   *
   * Use |EC_KEY_marshal_curve_name| instead. */
  OPENSSL_EXPORT int i2d_ECParameters(const EC_KEY *key, uint8_t **outp);
  
  /* o2i_ECPublicKey parses an EC point from |len| bytes at |*inp| into
   * |*out_key|. Note that this differs from the d2i format in that |*out_key|
   * must be non-NULL with a group set. On successful exit, |*inp| is advanced by
   * |len| bytes. It returns |*out_key| or NULL on error.
   *
   * Use |EC_POINT_oct2point| instead. */
  OPENSSL_EXPORT EC_KEY *o2i_ECPublicKey(EC_KEY **out_key, const uint8_t **inp,
                                         long len);
  
  /* i2o_ECPublicKey marshals an EC point from |key|. If |outp| is not NULL then
   * the result is written to |*outp| and |*outp| is advanced just past the
   * output. It returns the number of bytes in the result, whether written or
   * not, or a negative value on error.
   *
   * Use |EC_POINT_point2cbb| instead. */
  OPENSSL_EXPORT int i2o_ECPublicKey(const EC_KEY *key, unsigned char **outp);
  
  
  #if defined(__cplusplus)
  }  /* extern C */
  
  extern "C++" {
  
  namespace bssl {
  
  BORINGSSL_MAKE_DELETER(EC_KEY, EC_KEY_free)
  
  }  // namespace bssl
  
  }  /* extern C++ */
  
  #endif
  
  #endif  /* OPENSSL_HEADER_EC_KEY_H */
  