1DGST(1)                             OpenSSL                            DGST(1)
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NAME

6       openssl-dgst, dgst - perform digest operations
7

SYNOPSIS

9       openssl dgst [-digest] [-help] [-c] [-d] [-list] [-hex] [-binary] [-r]
10       [-out filename] [-sign filename] [-keyform arg] [-passin arg] [-verify
11       filename] [-prverify filename] [-signature filename] [-sigopt nm:v]
12       [-hmac key] [-fips-fingerprint] [-rand file...]  [-engine id]
13       [-engine_impl] [file...]
14
15       openssl digest [...]
16

DESCRIPTION

18       The digest functions output the message digest of a supplied file or
19       files in hexadecimal.  The digest functions also generate and verify
20       digital signatures using message digests.
21
22       The generic name, dgst, may be used with an option specifying the
23       algorithm to be used.  The default digest is sha256.  A supported
24       digest name may also be used as the command name.  To see the list of
25       supported algorithms, use the list --digest-commands command.
26

OPTIONS

28       -help
29           Print out a usage message.
30
31       -digest
32           Specifies name of a supported digest to be used. To see the list of
33           supported digests, use the command list --digest-commands.
34
35       -c  Print out the digest in two digit groups separated by colons, only
36           relevant if hex format output is used.
37
38       -d  Print out BIO debugging information.
39
40       -list
41           Prints out a list of supported message digests.
42
43       -hex
44           Digest is to be output as a hex dump. This is the default case for
45           a "normal" digest as opposed to a digital signature.  See NOTES
46           below for digital signatures using -hex.
47
48       -binary
49           Output the digest or signature in binary form.
50
51       -r  Output the digest in the "coreutils" format, including newlines.
52           Used by programs like sha1sum.
53
54       -out filename
55           Filename to output to, or standard output by default.
56
57       -sign filename
58           Digitally sign the digest using the private key in "filename". Note
59           this option does not support Ed25519 or Ed448 private keys.
60
61       -keyform arg
62           Specifies the key format to sign digest with. The DER, PEM, P12,
63           and ENGINE formats are supported.
64
65       -sigopt nm:v
66           Pass options to the signature algorithm during sign or verify
67           operations.  Names and values of these options are algorithm-
68           specific.
69
70       -passin arg
71           The private key password source. For more information about the
72           format of arg see "Pass Phrase Options" in openssl(1).
73
74       -verify filename
75           Verify the signature using the public key in "filename".  The
76           output is either "Verification OK" or "Verification Failure".
77
78       -prverify filename
79           Verify the signature using the private key in "filename".
80
81       -signature filename
82           The actual signature to verify.
83
84       -hmac key
85           Create a hashed MAC using "key".
86
87       -mac alg
88           Create MAC (keyed Message Authentication Code). The most popular
89           MAC algorithm is HMAC (hash-based MAC), but there are other MAC
90           algorithms which are not based on hash, for instance gost-mac
91           algorithm, supported by ccgost engine. MAC keys and other options
92           should be set via -macopt parameter.
93
94       -macopt nm:v
95           Passes options to MAC algorithm, specified by -mac key.  Following
96           options are supported by both by HMAC and gost-mac:
97
98           key:string
99               Specifies MAC key as alphanumeric string (use if key contain
100               printable characters only). String length must conform to any
101               restrictions of the MAC algorithm for example exactly 32 chars
102               for gost-mac.
103
104           hexkey:string
105               Specifies MAC key in hexadecimal form (two hex digits per
106               byte).  Key length must conform to any restrictions of the MAC
107               algorithm for example exactly 32 chars for gost-mac.
108
109       -rand file...
110           A file or files containing random data used to seed the random
111           number generator.  Multiple files can be specified separated by an
112           OS-dependent character.  The separator is ; for MS-Windows, , for
113           OpenVMS, and : for all others.
114
115       [-writerand file]
116           Writes random data to the specified file upon exit.  This can be
117           used with a subsequent -rand flag.
118
119       -fips-fingerprint
120           Compute HMAC using a specific key for certain OpenSSL-FIPS
121           operations.
122
123       -engine id
124           Use engine id for operations (including private key storage).  This
125           engine is not used as source for digest algorithms, unless it is
126           also specified in the configuration file or -engine_impl is also
127           specified.
128
129       -engine_impl
130           When used with the -engine option, it specifies to also use engine
131           id for digest operations.
132
133       file...
134           File or files to digest. If no files are specified then standard
135           input is used.
136

EXAMPLES

138       To create a hex-encoded message digest of a file:
139        openssl dgst -md5 -hex file.txt
140
141       To sign a file using SHA-256 with binary file output:
142        openssl dgst -sha256 -sign privatekey.pem -out signature.sign file.txt
143
144       To verify a signature:
145        openssl dgst -sha256 -verify publickey.pem \
146        -signature signature.sign \
147        file.txt
148

NOTES

150       The digest mechanisms that are available will depend on the options
151       used when building OpenSSL.  The list digest-commands command can be
152       used to list them.
153
154       New or agile applications should use probably use SHA-256. Other
155       digests, particularly SHA-1 and MD5, are still widely used for
156       interoperating with existing formats and protocols.
157
158       When signing a file, dgst will automatically determine the algorithm
159       (RSA, ECC, etc) to use for signing based on the private key's ASN.1
160       info.  When verifying signatures, it only handles the RSA, DSA, or
161       ECDSA signature itself, not the related data to identify the signer and
162       algorithm used in formats such as x.509, CMS, and S/MIME.
163
164       A source of random numbers is required for certain signing algorithms,
165       in particular ECDSA and DSA.
166
167       The signing and verify options should only be used if a single file is
168       being signed or verified.
169
170       Hex signatures cannot be verified using openssl.  Instead, use "xxd -r"
171       or similar program to transform the hex signature into a binary
172       signature prior to verification.
173

HISTORY

175       The default digest was changed from MD5 to SHA256 in OpenSSL 1.1.0.
176       The FIPS-related options were removed in OpenSSL 1.1.0.
177

179       Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.
180
181       Licensed under the OpenSSL license (the "License").  You may not use
182       this file except in compliance with the License.  You can obtain a copy
183       in the file LICENSE in the source distribution or at
184       <https://www.openssl.org/source/license.html>.
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1881.1.1l                            2021-09-15                           DGST(1)
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