1=pod
2{- OpenSSL::safe::output_do_not_edit_headers(); -}
3
4=head1 NAME
5
6openssl-mac - perform Message Authentication Code operations
7
8=head1 SYNOPSIS
9
10B<openssl mac>
11[B<-help>]
12[B<-cipher>]
13[B<-digest>]
14[B<-macopt>]
15[B<-in> I<filename>]
16[B<-out> I<filename>]
17[B<-binary>]
18{- $OpenSSL::safe::opt_provider_synopsis -}
19I<mac_name>
20
21=head1 DESCRIPTION
22
23The message authentication code functions output the MAC of a supplied input
24file.
25
26=head1 OPTIONS
27
28=over 4
29
30=item B<-help>
31
32Print a usage message.
33
34=item B<-in> I<filename>
35
36Input filename to calculate a MAC for, or standard input by default.
37Standard input is used if the filename is '-'.
38Files and standard input are expected to be in binary format.
39
40=item B<-out> I<filename>
41
42Filename to output to, or standard output by default.
43
44=item B<-binary>
45
46Output the MAC in binary form. Uses hexadecimal text format if not specified.
47
48=item B<-cipher> I<name>
49
50Used by CMAC and GMAC to specify the cipher algorithm.
51For CMAC it must be one of AES-128-CBC, AES-192-CBC, AES-256-CBC or
52DES-EDE3-CBC.
53For GMAC it should be a GCM mode cipher e.g. AES-128-GCM.
54
55=item B<-digest> I<name>
56
57Used by HMAC as an alphanumeric string (use if the key contains printable
58characters only).
59The string length must conform to any restrictions of the MAC algorithm.
60To see the list of supported digests, use C<openssl list -digest-commands>.
61
62=item B<-macopt> I<nm>:I<v>
63
64Passes options to the MAC algorithm.
65A comprehensive list of controls can be found in the EVP_MAC implementation
66documentation.
67Common parameter names used by EVP_MAC_CTX_get_params() are:
68
69=over 4
70
71=item B<key:>I<string>
72
73Specifies the MAC key as an alphanumeric string (use if the key contains
74printable characters only).
75The string length must conform to any restrictions of the MAC algorithm.
76A key must be specified for every MAC algorithm.
77
78=item B<hexkey:>I<string>
79
80Specifies the MAC key in hexadecimal form (two hex digits per byte).
81The key length must conform to any restrictions of the MAC algorithm.
82A key must be specified for every MAC algorithm.
83
84=item B<iv:>I<string>
85
86Used by GMAC to specify an IV as an alphanumeric string (use if the IV contains
87printable characters only).
88
89=item B<hexiv:>I<string>
90
91Used by GMAC to specify an IV in hexadecimal form (two hex digits per byte).
92
93=item B<size:>I<int>
94
95Used by KMAC128 or KMAC256 to specify an output length.
96The default sizes are 32 or 64 bytes respectively.
97
98=item B<custom:>I<string>
99
100Used by KMAC128 or KMAC256 to specify a customization string.
101The default is the empty string "".
102
103=item B<digest:>I<string>
104
105This option is identical to the B<-digest> option.
106
107=item B<cipher:>I<string>
108
109This option is identical to the B<-cipher> option.
110
111=back
112
113{- $OpenSSL::safe::opt_provider_item -}
114
115=item I<mac_name>
116
117Specifies the name of a supported MAC algorithm which will be used.
118To see the list of supported MAC's use the command C<openssl list
119-mac-algorithms>.
120
121=back
122
123
124=head1 EXAMPLES
125
126To create a hex-encoded HMAC-SHA1 MAC of a file and write to stdout: \
127 openssl mac -digest SHA1 \
128         -macopt hexkey:000102030405060708090A0B0C0D0E0F10111213 \
129         -in msg.bin HMAC
130
131To create a SipHash MAC from a file with a binary file output: \
132 openssl mac -macopt hexkey:000102030405060708090A0B0C0D0E0F \
133         -in msg.bin -out out.bin -binary SipHash
134
135To create a hex-encoded CMAC-AES-128-CBC MAC from a file:\
136 openssl mac -cipher AES-128-CBC \
137         -macopt hexkey:77A77FAF290C1FA30C683DF16BA7A77B \
138         -in msg.bin CMAC
139
140To create a hex-encoded KMAC128 MAC from a file with a Customisation String
141'Tag' and output length of 16: \
142 openssl mac -macopt custom:Tag -macopt hexkey:40414243444546 \
143         -macopt size:16 -in msg.bin KMAC128
144
145To create a hex-encoded GMAC-AES-128-GCM with a IV from a file: \
146 openssl mac -cipher AES-128-GCM -macopt hexiv:E0E00F19FED7BA0136A797F3 \
147         -macopt hexkey:77A77FAF290C1FA30C683DF16BA7A77B -in msg.bin GMAC
148
149=head1 NOTES
150
151The MAC mechanisms that are available will depend on the options
152used when building OpenSSL.
153Use C<openssl list -mac-algorithms> to list them.
154
155=head1 SEE ALSO
156
157L<openssl(1)>,
158L<EVP_MAC(3)>,
159L<EVP_MAC-CMAC(7)>,
160L<EVP_MAC-GMAC(7)>,
161L<EVP_MAC-HMAC(7)>,
162L<EVP_MAC-KMAC(7)>,
163L<EVP_MAC-Siphash(7)>,
164L<EVP_MAC-Poly1305(7)>
165
166=head1 COPYRIGHT
167
168Copyright 2018-2022 The OpenSSL Project Authors. All Rights Reserved.
169
170Licensed under the Apache License 2.0 (the "License").  You may not use
171this file except in compliance with the License.  You can obtain a copy
172in the file LICENSE in the source distribution or at
173L<https://www.openssl.org/source/license.html>.
174
175=cut
176