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EVP_SIGNATURE-ED25519(7)	    OpenSSL	      EVP_SIGNATURE-ED25519(7)

       EVP_SIGNATURE-ED25519, EVP_SIGNATURE-ED448, Ed25519, Ed448 - EVP_PKEY
       Ed25519 and Ed448 support

       The Ed25519 and Ed448 EVP_PKEY implementation supports key generation,
       one-shot	digest sign and	digest verify using PureEdDSA and Ed25519 or
       Ed448 (see RFC8032). It has associated private and public key formats
       compatible with RFC 8410.

       No additional parameters	can be set during one-shot signing or
       verification.  In particular, because PureEdDSA is used,	a digest must
       NOT be specified	when signing or	verifying.  See	EVP_PKEY-X25519(7) for
       information related to X25519 and X448 keys.

       The PureEdDSA algorithm does not	support	the streaming mechanism	of
       other signature algorithms using, for example, EVP_DigestUpdate().  The
       message to sign or verify must be passed	using the one-shot
       EVP_DigestSign()	and EVP_DigestVerify() functions.

       When calling EVP_DigestSignInit() or EVP_DigestVerifyInit(), the	digest
       type parameter MUST be set to NULL.

       Applications wishing to sign certificates (or other structures such as
       CRLs or certificate requests) using Ed25519 or Ed448 can	either use
       X509_sign() or X509_sign_ctx() in the usual way.

       Ed25519 or Ed448	private	keys can be set	directly using
       EVP_PKEY_new_raw_private_key(3) or loaded from a	PKCS#8 private key
       file using PEM_read_bio_PrivateKey(3) (or similar function). Completely
       new keys	can also be generated (see the example below). Setting a
       private key also	sets the associated public key.

       Ed25519 or Ed448	public keys can	be set directly	using
       EVP_PKEY_new_raw_public_key(3) or loaded	from a SubjectPublicKeyInfo
       structure in a PEM file using PEM_read_bio_PUBKEY(3) (or	similar

       Ed25519 and Ed448 can be	tested with the	openssl-speed(1) application
       since version 1.1.1.  Valid algorithm names are ed25519,	ed448 and
       eddsa. If eddsa is specified, then both Ed25519 and Ed448 are

       To sign a message using a ED25519 or ED448 key:

	   void	do_sign(EVP_PKEY *ed_key, unsigned char	*msg, size_t msg_len)
	       size_t sig_len;
	       unsigned	char *sig = NULL;
	       EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();

	       EVP_DigestSignInit(md_ctx, NULL,	NULL, NULL, ed_key);
	       /* Calculate the	requires size for the signature	by passing a NULL buffer */
	       EVP_DigestSign(md_ctx, NULL, &sig_len, msg, msg_len);
	       sig = OPENSSL_zalloc(sig_len);

	       EVP_DigestSign(md_ctx, sig, &sig_len, msg, msg_len);

       EVP_PKEY-X25519(7) provider-signature(7), EVP_DigestSignInit(3),

       Copyright 2017-2020 The OpenSSL Project Authors.	All Rights Reserved.

       Licensed	under the Apache License 2.0 (the "License").  You may not use
       this file except	in compliance with the License.	 You can obtain	a copy
       in the file LICENSE in the source distribution or at

3.0.0-alpha6			  2020-08-06	      EVP_SIGNATURE-ED25519(7)


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