xref: /freebsd-src/crypto/openssl/doc/man7/EVP_SIGNATURE-ED25519.pod (revision b077aed33b7b6aefca7b17ddb250cf521f938613)
1*b077aed3SPierre Pronchery=pod
2*b077aed3SPierre Pronchery
3*b077aed3SPierre Pronchery=head1 NAME
4*b077aed3SPierre Pronchery
5*b077aed3SPierre ProncheryEVP_SIGNATURE-ED25519,
6*b077aed3SPierre ProncheryEVP_SIGNATURE-ED448,
7*b077aed3SPierre ProncheryEd25519,
8*b077aed3SPierre ProncheryEd448
9*b077aed3SPierre Pronchery- EVP_PKEY Ed25519 and Ed448 support
10*b077aed3SPierre Pronchery
11*b077aed3SPierre Pronchery=head1 DESCRIPTION
12*b077aed3SPierre Pronchery
13*b077aed3SPierre ProncheryThe B<Ed25519> and B<Ed448> EVP_PKEY implementation supports key generation,
14*b077aed3SPierre Proncheryone-shot digest sign and digest verify using PureEdDSA and B<Ed25519> or B<Ed448>
15*b077aed3SPierre Pronchery(see RFC8032). It has associated private and public key formats compatible with
16*b077aed3SPierre ProncheryRFC 8410.
17*b077aed3SPierre Pronchery
18*b077aed3SPierre Pronchery=head2 ED25519 and ED448 Signature Parameters
19*b077aed3SPierre Pronchery
20*b077aed3SPierre ProncheryNo additional parameters can be set during one-shot signing or verification.
21*b077aed3SPierre ProncheryIn particular, because PureEdDSA is used, a digest must B<NOT> be specified when
22*b077aed3SPierre Proncherysigning or verifying.
23*b077aed3SPierre ProncherySee L<EVP_PKEY-X25519(7)> for information related to B<X25519> and B<X448> keys.
24*b077aed3SPierre Pronchery
25*b077aed3SPierre ProncheryThe following signature parameters can be retrieved using
26*b077aed3SPierre ProncheryEVP_PKEY_CTX_get_params().
27*b077aed3SPierre Pronchery
28*b077aed3SPierre Pronchery=over 4
29*b077aed3SPierre Pronchery
30*b077aed3SPierre Pronchery=item "algorithm-id" (B<OSSL_SIGNATURE_PARAM_ALGORITHM_ID>) <octet string>
31*b077aed3SPierre Pronchery
32*b077aed3SPierre ProncheryThe parameters are described in L<provider-signature(7)>.
33*b077aed3SPierre Pronchery
34*b077aed3SPierre Pronchery=back
35*b077aed3SPierre Pronchery
36*b077aed3SPierre Pronchery=head1 NOTES
37*b077aed3SPierre Pronchery
38*b077aed3SPierre ProncheryThe PureEdDSA algorithm does not support the streaming mechanism
39*b077aed3SPierre Proncheryof other signature algorithms using, for example, EVP_DigestUpdate().
40*b077aed3SPierre ProncheryThe message to sign or verify must be passed using the one-shot
41*b077aed3SPierre ProncheryEVP_DigestSign() and EVP_DigestVerify() functions.
42*b077aed3SPierre Pronchery
43*b077aed3SPierre ProncheryWhen calling EVP_DigestSignInit() or EVP_DigestVerifyInit(), the
44*b077aed3SPierre Proncherydigest I<type> parameter B<MUST> be set to NULL.
45*b077aed3SPierre Pronchery
46*b077aed3SPierre ProncheryApplications wishing to sign certificates (or other structures such as
47*b077aed3SPierre ProncheryCRLs or certificate requests) using Ed25519 or Ed448 can either use X509_sign()
48*b077aed3SPierre Proncheryor X509_sign_ctx() in the usual way.
49*b077aed3SPierre Pronchery
50*b077aed3SPierre ProncheryEd25519 or Ed448 private keys can be set directly using
51*b077aed3SPierre ProncheryL<EVP_PKEY_new_raw_private_key(3)> or loaded from a PKCS#8 private key file
52*b077aed3SPierre Proncheryusing L<PEM_read_bio_PrivateKey(3)> (or similar function). Completely new keys
53*b077aed3SPierre Proncherycan also be generated (see the example below). Setting a private key also sets
54*b077aed3SPierre Proncherythe associated public key.
55*b077aed3SPierre Pronchery
56*b077aed3SPierre ProncheryEd25519 or Ed448 public keys can be set directly using
57*b077aed3SPierre ProncheryL<EVP_PKEY_new_raw_public_key(3)> or loaded from a SubjectPublicKeyInfo
58*b077aed3SPierre Proncherystructure in a PEM file using L<PEM_read_bio_PUBKEY(3)> (or similar function).
59*b077aed3SPierre Pronchery
60*b077aed3SPierre ProncheryEd25519 and Ed448 can be tested with the L<openssl-speed(1)> application
61*b077aed3SPierre Proncherysince version 1.1.1.
62*b077aed3SPierre ProncheryValid algorithm names are B<ed25519>, B<ed448> and B<eddsa>. If B<eddsa> is
63*b077aed3SPierre Proncheryspecified, then both Ed25519 and Ed448 are benchmarked.
64*b077aed3SPierre Pronchery
65*b077aed3SPierre Pronchery=head1 EXAMPLES
66*b077aed3SPierre Pronchery
67*b077aed3SPierre ProncheryTo sign a message using a ED25519 or ED448 key:
68*b077aed3SPierre Pronchery
69*b077aed3SPierre Pronchery    void do_sign(EVP_PKEY *ed_key, unsigned char *msg, size_t msg_len)
70*b077aed3SPierre Pronchery    {
71*b077aed3SPierre Pronchery        size_t sig_len;
72*b077aed3SPierre Pronchery        unsigned char *sig = NULL;
73*b077aed3SPierre Pronchery        EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
74*b077aed3SPierre Pronchery
75*b077aed3SPierre Pronchery        EVP_DigestSignInit(md_ctx, NULL, NULL, NULL, ed_key);
76*b077aed3SPierre Pronchery        /* Calculate the requires size for the signature by passing a NULL buffer */
77*b077aed3SPierre Pronchery        EVP_DigestSign(md_ctx, NULL, &sig_len, msg, msg_len);
78*b077aed3SPierre Pronchery        sig = OPENSSL_zalloc(sig_len);
79*b077aed3SPierre Pronchery
80*b077aed3SPierre Pronchery        EVP_DigestSign(md_ctx, sig, &sig_len, msg, msg_len);
81*b077aed3SPierre Pronchery        ...
82*b077aed3SPierre Pronchery        OPENSSL_free(sig);
83*b077aed3SPierre Pronchery        EVP_MD_CTX_free(md_ctx);
84*b077aed3SPierre Pronchery    }
85*b077aed3SPierre Pronchery
86*b077aed3SPierre Pronchery=head1 SEE ALSO
87*b077aed3SPierre Pronchery
88*b077aed3SPierre ProncheryL<EVP_PKEY-X25519(7)>
89*b077aed3SPierre ProncheryL<provider-signature(7)>,
90*b077aed3SPierre ProncheryL<EVP_DigestSignInit(3)>,
91*b077aed3SPierre ProncheryL<EVP_DigestVerifyInit(3)>,
92*b077aed3SPierre Pronchery
93*b077aed3SPierre Pronchery=head1 COPYRIGHT
94*b077aed3SPierre Pronchery
95*b077aed3SPierre ProncheryCopyright 2017-2021 The OpenSSL Project Authors. All Rights Reserved.
96*b077aed3SPierre Pronchery
97*b077aed3SPierre ProncheryLicensed under the Apache License 2.0 (the "License").  You may not use
98*b077aed3SPierre Proncherythis file except in compliance with the License.  You can obtain a copy
99*b077aed3SPierre Proncheryin the file LICENSE in the source distribution or at
100*b077aed3SPierre ProncheryL<https://www.openssl.org/source/license.html>.
101*b077aed3SPierre Pronchery
102*b077aed3SPierre Pronchery=cut
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