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✏️ Editing: DH_size.3

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.\" ========================================================================
.\"
.IX Title "DH_SIZE 3"
.TH DH_SIZE 3 "2023-09-11" "1.1.1w" "OpenSSL"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
DH_size, DH_bits, DH_security_bits \- get Diffie\-Hellman prime size and security bits
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <openssl/dh.h>
\&
\& int DH_size(const DH *dh);
\&
\& int DH_bits(const DH *dh);
\&
\& int DH_security_bits(const DH *dh);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\fBDH_size()\fR returns the Diffie-Hellman prime size in bytes. It can be used
to determine how much memory must be allocated for the shared secret
computed by \fBDH_compute_key\fR\|(3).
.PP
\&\fBDH_bits()\fR returns the number of significant bits.
.PP
\&\fBdh\fR and \fBdh\->p\fR must not be \fB\s-1NULL\s0\fR.
.PP
\&\fBDH_security_bits()\fR returns the number of security bits of the given \fBdh\fR
key. See \fBBN_security_bits\fR\|(3).
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fBDH_size()\fR returns the prime size of Diffie-Hellman in bytes.
.PP
\&\fBDH_bits()\fR returns the number of bits in the key.
.PP
\&\fBDH_security_bits()\fR returns the number of security bits.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBDH_new\fR\|(3), \fBDH_generate_key\fR\|(3),
\&\fBBN_num_bits\fR\|(3)
.SH "HISTORY"
.IX Header "HISTORY"
The \fBDH_bits()\fR function was added in OpenSSL 1.1.0.
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2000\-2018 The OpenSSL Project Authors. All Rights Reserved.
.PP
Licensed under the OpenSSL license (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>.

MR SKB