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✏️ Editing: RSA_blinding_on.3

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.\" ========================================================================
.\"
.IX Title "RSA_BLINDING_ON 3"
.TH RSA_BLINDING_ON 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"
RSA_blinding_on, RSA_blinding_off \- protect the RSA operation from timing attacks
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <openssl/rsa.h>
\&
\& int RSA_blinding_on(RSA *rsa, BN_CTX *ctx);
\&
\& void RSA_blinding_off(RSA *rsa);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\s-1RSA\s0 is vulnerable to timing attacks. In a setup where attackers can
measure the time of \s-1RSA\s0 decryption or signature operations, blinding
must be used to protect the \s-1RSA\s0 operation from that attack.
.PP
\&\fBRSA_blinding_on()\fR turns blinding on for key \fBrsa\fR and generates a
random blinding factor. \fBctx\fR is \fB\s-1NULL\s0\fR or a preallocated and
initialized \fB\s-1BN_CTX\s0\fR.
.PP
\&\fBRSA_blinding_off()\fR turns blinding off and frees the memory used for
the blinding factor.
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fBRSA_blinding_on()\fR returns 1 on success, and 0 if an error occurred.
.PP
\&\fBRSA_blinding_off()\fR returns no value.
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2000\-2020 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