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.\" ========================================================================
.\"
.IX Title "EVP_KEYEXCH-X25519 7"
.TH EVP_KEYEXCH-X25519 7 "2023-05-07" "3.0.9" "OpenSSL"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
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.nh
.SH "NAME"
EVP_KEYEXCH\-X25519,
EVP_KEYEXCH\-X448
\&\- X25519 and X448 Key Exchange algorithm support
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
Key exchange support for the \fBX25519\fR and \fBX448\fR key types.
.SS "Key exchange parameters"
.IX Subsection "Key exchange parameters"
.ie n .IP """pad"" (\fB\s-1OSSL_EXCHANGE_PARAM_PAD\s0\fR) <unsigned integer>" 4
.el .IP "``pad'' (\fB\s-1OSSL_EXCHANGE_PARAM_PAD\s0\fR) <unsigned integer>" 4
.IX Item "pad (OSSL_EXCHANGE_PARAM_PAD) <unsigned integer>"
See \*(L"Common Key Exchange parameters\*(R" in \fBprovider\-keyexch\fR\|(7).
.SH "EXAMPLES"
.IX Header "EXAMPLES"
Keys for the host and peer can be generated as shown in
\&\*(L"Examples\*(R" in \s-1\fBEVP_PKEY\-X25519\s0\fR\|(7).
.PP
The code to generate a shared secret is identical to
\&\*(L"Examples\*(R" in \s-1\fBEVP_KEYEXCH\-DH\s0\fR\|(7).
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\s-1\fBEVP_PKEY\-FFC\s0\fR\|(7),
\&\s-1\fBEVP_PKEY\-DH\s0\fR\|(7)
\&\s-1\fBEVP_PKEY\s0\fR\|(3),
\&\fBprovider\-keyexch\fR\|(7),
\&\fBprovider\-keymgmt\fR\|(7),
\&\fBOSSL_PROVIDER\-default\fR\|(7),
\&\s-1\fBOSSL_PROVIDER\-FIPS\s0\fR\|(7),
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
.PP
Licensed under the Apache License 2.0 (the \*(L"License\*(R").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file \s-1LICENSE\s0 in the source distribution or at
<https://www.openssl.org/source/license.html>.