Android_verify/third_party/android-libs/share/man/man7/EVP_MAC-HMAC.7ossl

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.\" ========================================================================
.\"
.IX Title "EVP_MAC-HMAC 7ossl"
.TH EVP_MAC-HMAC 7ossl "2024-09-03" "3.3.2" "OpenSSL"
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.nh
.SH "NAME"
EVP_MAC\-HMAC \- The HMAC EVP_MAC implementation
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
Support for computing \s-1HMAC\s0 MACs through the \fB\s-1EVP_MAC\s0\fR \s-1API.\s0
.PP
This implementation uses \s-1EVP_MD\s0 functions to get access to the underlying
digest.
.SS "Identity"
.IX Subsection "Identity"
This implementation is identified with this name and properties, to be
used with \fBEVP_MAC_fetch()\fR:
.ie n .IP """\s-1HMAC"",\s0 ""provider=default"" or ""provider=fips""" 4
.el .IP "``\s-1HMAC'',\s0 ``provider=default'' or ``provider=fips''" 4
.IX Item "HMAC, provider=default or provider=fips"
.SS "Supported parameters"
.IX Subsection "Supported parameters"
The general description of these parameters can be found in
\&\*(L"\s-1PARAMETERS\*(R"\s0 in \s-1\fBEVP_MAC\s0\fR\|(3).
.PP
The following parameter can be set with \fBEVP_MAC_CTX_set_params()\fR:
.ie n .IP """key"" (\fB\s-1OSSL_MAC_PARAM_KEY\s0\fR) <octet string>" 4
.el .IP "``key'' (\fB\s-1OSSL_MAC_PARAM_KEY\s0\fR) <octet string>" 4
.IX Item "key (OSSL_MAC_PARAM_KEY) <octet string>"
Sets the \s-1MAC\s0 key.
Setting this parameter is identical to passing a \fIkey\fR to \fBEVP_MAC_init\fR\|(3).
.ie n .IP """digest"" (\fB\s-1OSSL_MAC_PARAM_DIGEST\s0\fR) <\s-1UTF8\s0 string>" 4
.el .IP "``digest'' (\fB\s-1OSSL_MAC_PARAM_DIGEST\s0\fR) <\s-1UTF8\s0 string>" 4
.IX Item "digest (OSSL_MAC_PARAM_DIGEST) <UTF8 string>"
Sets the name of the underlying digest to be used.
.ie n .IP """properties"" (\fB\s-1OSSL_MAC_PARAM_PROPERTIES\s0\fR) <\s-1UTF8\s0 string>" 4
.el .IP "``properties'' (\fB\s-1OSSL_MAC_PARAM_PROPERTIES\s0\fR) <\s-1UTF8\s0 string>" 4
.IX Item "properties (OSSL_MAC_PARAM_PROPERTIES) <UTF8 string>"
Sets the properties to be queried when trying to fetch the underlying digest.
This must be given together with the digest naming parameter (\*(L"digest\*(R", or
\&\fB\s-1OSSL_MAC_PARAM_DIGEST\s0\fR) to be considered valid.
.ie n .IP """digest-noinit"" (\fB\s-1OSSL_MAC_PARAM_DIGEST_NOINIT\s0\fR) <integer>" 4
.el .IP "``digest-noinit'' (\fB\s-1OSSL_MAC_PARAM_DIGEST_NOINIT\s0\fR) <integer>" 4
.IX Item "digest-noinit (OSSL_MAC_PARAM_DIGEST_NOINIT) <integer>"
A flag to set the \s-1MAC\s0 digest to not initialise the implementation
specific data.
The value 0 or 1 is expected.
This option is deprecated and will be removed in a future release.
It may be set but is currently ignored
.ie n .IP """digest-oneshot"" (\fB\s-1OSSL_MAC_PARAM_DIGEST_ONESHOT\s0\fR) <integer>" 4
.el .IP "``digest-oneshot'' (\fB\s-1OSSL_MAC_PARAM_DIGEST_ONESHOT\s0\fR) <integer>" 4
.IX Item "digest-oneshot (OSSL_MAC_PARAM_DIGEST_ONESHOT) <integer>"
A flag to set the \s-1MAC\s0 digest to be a one-shot operation.
The value 0 or 1 is expected.
This option is deprecated and will be removed in a future release.
It may be set but is currently ignored.
.ie n .IP """tls-data-size"" (\fB\s-1OSSL_MAC_PARAM_TLS_DATA_SIZE\s0\fR) <unsigned integer>" 4
.el .IP "``tls-data-size'' (\fB\s-1OSSL_MAC_PARAM_TLS_DATA_SIZE\s0\fR) <unsigned integer>" 4
.IX Item "tls-data-size (OSSL_MAC_PARAM_TLS_DATA_SIZE) <unsigned integer>"
.PP
The following parameter can be retrieved with \fBEVP_MAC_CTX_get_params()\fR:
.ie n .IP """size"" (\fB\s-1OSSL_MAC_PARAM_SIZE\s0\fR) <unsigned integer>" 4
.el .IP "``size'' (\fB\s-1OSSL_MAC_PARAM_SIZE\s0\fR) <unsigned integer>" 4
.IX Item "size (OSSL_MAC_PARAM_SIZE) <unsigned integer>"
The \*(L"size\*(R" parameter can also be retrieved with \fBEVP_MAC_CTX_get_mac_size()\fR.
The length of the \*(L"size\*(R" parameter is equal to that of an \fBunsigned int\fR.
.ie n .IP """block-size"" (\fB\s-1OSSL_MAC_PARAM_BLOCK_SIZE\s0\fR) <unsigned integer>" 4
.el .IP "``block-size'' (\fB\s-1OSSL_MAC_PARAM_BLOCK_SIZE\s0\fR) <unsigned integer>" 4
.IX Item "block-size (OSSL_MAC_PARAM_BLOCK_SIZE) <unsigned integer>"
Gets the \s-1MAC\s0 block size.  The \*(L"block-size\*(R" parameter can also be retrieved with
\&\fBEVP_MAC_CTX_get_block_size()\fR.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBEVP_MAC_CTX_get_params\fR\|(3), \fBEVP_MAC_CTX_set_params\fR\|(3),
\&\*(L"\s-1PARAMETERS\*(R"\s0 in \s-1\fBEVP_MAC\s0\fR\|(3), \s-1\fBOSSL_PARAM\s0\fR\|(3), \s-1\fBHMAC\s0\fR\|(3)
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2018\-2021 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>.