+ const EC_KEY *ecdh,
+ void *(*KDF) (const void *in, size_t inlen,
+ void *out, size_t *outlen));
+
+typedef struct ECDSA_SIG_st ECDSA_SIG;
+
+/** Allocates and initialize a ECDSA_SIG structure
+ * \return pointer to a ECDSA_SIG structure or NULL if an error occurred
+ */
+ECDSA_SIG *ECDSA_SIG_new(void);
+
+/** frees a ECDSA_SIG structure
+ * \param sig pointer to the ECDSA_SIG structure
+ */
+void ECDSA_SIG_free(ECDSA_SIG *sig);
+
+/** DER encode content of ECDSA_SIG object (note: this function modifies *pp
+ * (*pp += length of the DER encoded signature)).
+ * \param sig pointer to the ECDSA_SIG object
+ * \param pp pointer to a unsigned char pointer for the output or NULL
+ * \return the length of the DER encoded ECDSA_SIG object or 0
+ */
+int i2d_ECDSA_SIG(const ECDSA_SIG *sig, unsigned char **pp);
+
+/** Decodes a DER encoded ECDSA signature (note: this function changes *pp
+ * (*pp += len)).
+ * \param sig pointer to ECDSA_SIG pointer (may be NULL)
+ * \param pp memory buffer with the DER encoded signature
+ * \param len length of the buffer
+ * \return pointer to the decoded ECDSA_SIG structure (or NULL)
+ */
+ECDSA_SIG *d2i_ECDSA_SIG(ECDSA_SIG **sig, const unsigned char **pp, long len);
+
+/** Accessor for r and s fields of ECDSA_SIG
+ * \param sig pointer to ECDSA_SIG pointer
+ * \param pr pointer to BIGNUM pointer for r (may be NULL)
+ * \param ps pointer to BIGNUM pointer for s (may be NULL)
+ */
+void ECDSA_SIG_get0(const ECDSA_SIG *sig, const BIGNUM **pr, const BIGNUM **ps);
+
+/** Setter for r and s fields of ECDSA_SIG
+ * \param sig pointer to ECDSA_SIG pointer
+ * \param r pointer to BIGNUM for r (may be NULL)
+ * \param s pointer to BIGNUM for s (may be NULL)
+ */
+int ECDSA_SIG_set0(ECDSA_SIG *sig, BIGNUM *r, BIGNUM *s);
+
+/** Computes the ECDSA signature of the given hash value using
+ * the supplied private key and returns the created signature.
+ * \param dgst pointer to the hash value
+ * \param dgst_len length of the hash value
+ * \param eckey EC_KEY object containing a private EC key
+ * \return pointer to a ECDSA_SIG structure or NULL if an error occurred
+ */
+ECDSA_SIG *ECDSA_do_sign(const unsigned char *dgst, int dgst_len,
+ EC_KEY *eckey);
+
+/** Computes ECDSA signature of a given hash value using the supplied
+ * private key (note: sig must point to ECDSA_size(eckey) bytes of memory).
+ * \param dgst pointer to the hash value to sign
+ * \param dgstlen length of the hash value
+ * \param kinv BIGNUM with a pre-computed inverse k (optional)
+ * \param rp BIGNUM with a pre-computed rp value (optional),
+ * see ECDSA_sign_setup
+ * \param eckey EC_KEY object containing a private EC key
+ * \return pointer to a ECDSA_SIG structure or NULL if an error occurred
+ */
+ECDSA_SIG *ECDSA_do_sign_ex(const unsigned char *dgst, int dgstlen,
+ const BIGNUM *kinv, const BIGNUM *rp,
+ EC_KEY *eckey);
+
+/** Verifies that the supplied signature is a valid ECDSA
+ * signature of the supplied hash value using the supplied public key.
+ * \param dgst pointer to the hash value
+ * \param dgst_len length of the hash value
+ * \param sig ECDSA_SIG structure
+ * \param eckey EC_KEY object containing a public EC key
+ * \return 1 if the signature is valid, 0 if the signature is invalid
+ * and -1 on error
+ */
+int ECDSA_do_verify(const unsigned char *dgst, int dgst_len,
+ const ECDSA_SIG *sig, EC_KEY *eckey);
+
+/** Precompute parts of the signing operation
+ * \param eckey EC_KEY object containing a private EC key
+ * \param ctx BN_CTX object (optional)
+ * \param kinv BIGNUM pointer for the inverse of k
+ * \param rp BIGNUM pointer for x coordinate of k * generator
+ * \return 1 on success and 0 otherwise
+ */
+int ECDSA_sign_setup(EC_KEY *eckey, BN_CTX *ctx, BIGNUM **kinv, BIGNUM **rp);
+
+/** Computes ECDSA signature of a given hash value using the supplied
+ * private key (note: sig must point to ECDSA_size(eckey) bytes of memory).
+ * \param type this parameter is ignored
+ * \param dgst pointer to the hash value to sign
+ * \param dgstlen length of the hash value
+ * \param sig memory for the DER encoded created signature
+ * \param siglen pointer to the length of the returned signature
+ * \param eckey EC_KEY object containing a private EC key
+ * \return 1 on success and 0 otherwise
+ */
+int ECDSA_sign(int type, const unsigned char *dgst, int dgstlen,
+ unsigned char *sig, unsigned int *siglen, EC_KEY *eckey);
+
+/** Computes ECDSA signature of a given hash value using the supplied
+ * private key (note: sig must point to ECDSA_size(eckey) bytes of memory).
+ * \param type this parameter is ignored
+ * \param dgst pointer to the hash value to sign
+ * \param dgstlen length of the hash value
+ * \param sig buffer to hold the DER encoded signature
+ * \param siglen pointer to the length of the returned signature
+ * \param kinv BIGNUM with a pre-computed inverse k (optional)
+ * \param rp BIGNUM with a pre-computed rp value (optional),
+ * see ECDSA_sign_setup
+ * \param eckey EC_KEY object containing a private EC key
+ * \return 1 on success and 0 otherwise
+ */
+int ECDSA_sign_ex(int type, const unsigned char *dgst, int dgstlen,
+ unsigned char *sig, unsigned int *siglen,
+ const BIGNUM *kinv, const BIGNUM *rp, EC_KEY *eckey);
+
+/** Verifies that the given signature is valid ECDSA signature
+ * of the supplied hash value using the specified public key.
+ * \param type this parameter is ignored
+ * \param dgst pointer to the hash value
+ * \param dgstlen length of the hash value
+ * \param sig pointer to the DER encoded signature
+ * \param siglen length of the DER encoded signature
+ * \param eckey EC_KEY object containing a public EC key
+ * \return 1 if the signature is valid, 0 if the signature is invalid
+ * and -1 on error
+ */
+int ECDSA_verify(int type, const unsigned char *dgst, int dgstlen,
+ const unsigned char *sig, int siglen, EC_KEY *eckey);
+
+/** Returns the maximum length of the DER encoded signature
+ * \param eckey EC_KEY object
+ * \return numbers of bytes required for the DER encoded signature
+ */
+int ECDSA_size(const EC_KEY *eckey);
+
+/********************************************************************/
+/* EC_KEY_METHOD constructors, destructors, writers and accessors */
+/********************************************************************/
+
+EC_KEY_METHOD *EC_KEY_METHOD_new(const EC_KEY_METHOD *meth);
+void EC_KEY_METHOD_free(EC_KEY_METHOD *meth);
+void EC_KEY_METHOD_set_init(EC_KEY_METHOD *meth,
+ int (*init)(EC_KEY *key),
+ void (*finish)(EC_KEY *key),
+ int (*copy)(EC_KEY *dest, const EC_KEY *src),
+ int (*set_group)(EC_KEY *key, const EC_GROUP *grp),
+ int (*set_private)(EC_KEY *key,
+ const BIGNUM *priv_key),
+ int (*set_public)(EC_KEY *key,
+ const EC_POINT *pub_key));
+
+void EC_KEY_METHOD_set_keygen(EC_KEY_METHOD *meth,
+ int (*keygen)(EC_KEY *key));
+
+void EC_KEY_METHOD_set_compute_key(EC_KEY_METHOD *meth,
+ int (*ckey)(unsigned char **psec,
+ size_t *pseclen,
+ const EC_POINT *pub_key,
+ const EC_KEY *ecdh));
+
+void EC_KEY_METHOD_set_sign(EC_KEY_METHOD *meth,
+ int (*sign)(int type, const unsigned char *dgst,
+ int dlen, unsigned char *sig,
+ unsigned int *siglen,
+ const BIGNUM *kinv, const BIGNUM *r,
+ EC_KEY *eckey),
+ int (*sign_setup)(EC_KEY *eckey, BN_CTX *ctx_in,
+ BIGNUM **kinvp, BIGNUM **rp),
+ ECDSA_SIG *(*sign_sig)(const unsigned char *dgst,
+ int dgst_len,
+ const BIGNUM *in_kinv,
+ const BIGNUM *in_r,
+ EC_KEY *eckey));
+
+void EC_KEY_METHOD_set_verify(EC_KEY_METHOD *meth,
+ int (*verify)(int type, const unsigned
+ char *dgst, int dgst_len,
+ const unsigned char *sigbuf,
+ int sig_len, EC_KEY *eckey),
+ int (*verify_sig)(const unsigned char *dgst,
+ int dgst_len,
+ const ECDSA_SIG *sig,
+ EC_KEY *eckey));
+
+void EC_KEY_METHOD_get_init(EC_KEY_METHOD *meth,
+ int (**pinit)(EC_KEY *key),
+ void (**pfinish)(EC_KEY *key),
+ int (**pcopy)(EC_KEY *dest, const EC_KEY *src),
+ int (**pset_group)(EC_KEY *key,
+ const EC_GROUP *grp),
+ int (**pset_private)(EC_KEY *key,
+ const BIGNUM *priv_key),
+ int (**pset_public)(EC_KEY *key,
+ const EC_POINT *pub_key));
+
+void EC_KEY_METHOD_get_keygen(EC_KEY_METHOD *meth,
+ int (**pkeygen)(EC_KEY *key));
+
+void EC_KEY_METHOD_get_compute_key(EC_KEY_METHOD *meth,
+ int (**pck)(unsigned char **psec,
+ size_t *pseclen,
+ const EC_POINT *pub_key,
+ const EC_KEY *ecdh));
+
+void EC_KEY_METHOD_get_sign(EC_KEY_METHOD *meth,
+ int (**psign)(int type, const unsigned char *dgst,
+ int dlen, unsigned char *sig,
+ unsigned int *siglen,
+ const BIGNUM *kinv, const BIGNUM *r,
+ EC_KEY *eckey),
+ int (**psign_setup)(EC_KEY *eckey, BN_CTX *ctx_in,
+ BIGNUM **kinvp, BIGNUM **rp),
+ ECDSA_SIG *(**psign_sig)(const unsigned char *dgst,
+ int dgst_len,
+ const BIGNUM *in_kinv,
+ const BIGNUM *in_r,
+ EC_KEY *eckey));
+
+void EC_KEY_METHOD_get_verify(EC_KEY_METHOD *meth,
+ int (**pverify)(int type, const unsigned
+ char *dgst, int dgst_len,
+ const unsigned char *sigbuf,
+ int sig_len, EC_KEY *eckey),
+ int (**pverify_sig)(const unsigned char *dgst,
+ int dgst_len,
+ const ECDSA_SIG *sig,
+ EC_KEY *eckey));