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hanyw@hanyw:~$ man openssl-dgst |grep -Ev "^#34;
OPENSSL-DGST(1SSL)                                                               OpenSSL                                                               OPENSSL-DGST(1SSL)
NAME
       openssl-dgst - perform digest operations
SYNOPSIS
       openssl dgst|digest [-digest] [-list] [-help] [-c] [-d] [-debug] [-hex] [-binary] [-xoflen length] [-r] [-out filename] [-sign filename|uri] [-keyform
       DER|PEM|P12|ENGINE] [-passin arg] [-verify filename] [-prverify filename] [-signature filename] [-sigopt nm:v] [-hmac key] [-mac alg] [-macopt nm:v]
       [-fips-fingerprint] [-engine id] [-engine_impl id] [-rand files] [-writerand file] [-provider name] [-provider-path path] [-propquery propq] [file ...]
DESCRIPTION
       This command output the message digest of a supplied file or files in hexadecimal, and also generates and verifies digital signatures using message digests.
       The generic name, openssl dgst, may be used with an option specifying the algorithm to be used.  The default digest is sha256.  A supported digest name may also
       be used as the sub-command name.  To see the list of supported algorithms, use "openssl list -digest-algorithms"
OPTIONS
       -help
           Print out a usage message.
       -digest
           Specifies name of a supported digest to be used. See option -list below :
       -list
           Prints out a list of supported message digests.
       -c  Print out the digest in two digit groups separated by colons, only relevant if the -hex option is given as well.
       -d, -debug
           Print out BIO debugging information.
       -hex
           Digest is to be output as a hex dump. This is the default case for a "normal" digest as opposed to a digital signature.  See NOTES below for digital
           signatures using -hex.
       -binary
           Output the digest or signature in binary form.
       -xoflen length
           Set the output length for XOF algorithms, such as shake128.
       -r  Output the digest in the "coreutils" format, including newlines.  Used by programs like sha1sum(1).
       -out filename
           Filename to output to, or standard output by default.
       -sign filename|uri
           Digitally sign the digest using the given private key. Note this option does not support Ed25519 or Ed448 private keys. Use the openssl-pkeyutl(1) command
           instead for this.
       -keyform DER|PEM|P12|ENGINE
           The format of the key to sign with; unspecified by default.  See openssl-format-options(1) for details.
       -sigopt nm:v
           Pass options to the signature algorithm during sign or verify operations.  Names and values of these options are algorithm-specific.
       -passin arg
           The private key password source. For more information about the format of arg see openssl-passphrase-options(1).
       -verify filename
           Verify the signature using the public key in "filename".  The output is either "Verified OK" or "Verification Failure".
       -prverify filename
           Verify the signature using the private key in "filename".
       -signature filename
           The actual signature to verify.
       -hmac key
           Create a hashed MAC using "key".
           The openssl-mac(1) command should be preferred to using this command line option.
       -mac alg
           Create MAC (keyed Message Authentication Code). The most popular MAC algorithm is HMAC (hash-based MAC), but there are other MAC algorithms which are not
           based on hash, for instance gost-mac algorithm, supported by the gost engine. MAC keys and other options should be set via -macopt parameter.
           The openssl-mac(1) command should be preferred to using this command line option.
       -macopt nm:v
           Passes options to MAC algorithm, specified by -mac key.  Following options are supported by both by HMAC and gost-mac:
           key:string
               Specifies MAC key as alphanumeric string (use if key contain printable characters only). String length must conform to any restrictions of the MAC
               algorithm for example exactly 32 chars for gost-mac.
           hexkey:string
               Specifies MAC key in hexadecimal form (two hex digits per byte).  Key length must conform to any restrictions of the MAC algorithm for example exactly 32
               chars for gost-mac.
           The openssl-mac(1) command should be preferred to using this command line option.
       -fips-fingerprint
           Compute HMAC using a specific key for certain OpenSSL-FIPS operations.
       -rand files, -writerand file
           See "Random State Options" in openssl(1) for details.
       -engine id
           See "Engine Options" in openssl(1).  This option is deprecated.
           The engine is not used for digests unless the -engine_impl option is used or it is configured to do so, see "Engine Configuration Module" in config(5).
       -engine_impl id
           When used with the -engine option, it specifies to also use engine id for digest operations.
       -provider name
       -provider-path path
       -propquery propq
           See "Provider Options" in openssl(1), provider(7), and property(7).
       file ...
           File or files to digest. If no files are specified then standard input is used.
EXAMPLES
       To create a hex-encoded message digest of a file:
        openssl dgst -md5 -hex file.txt
        or
        openssl md5 file.txt
       To sign a file using SHA-256 with binary file output:
        openssl dgst -sha256 -sign privatekey.pem -out signature.sign file.txt
        or
        openssl sha256 -sign privatekey.pem -out signature.sign file.txt
       To verify a signature:
        openssl dgst -sha256 -verify publickey.pem \
        -signature signature.sign \
        file.txt
NOTES
       The digest mechanisms that are available will depend on the options used when building OpenSSL.  The "openssl list -digest-algorithms" command can be used to list
       them.
       New or agile applications should use probably use SHA-256. Other digests, particularly SHA-1 and MD5, are still widely used for interoperating with existing
       formats and protocols.
       When signing a file, this command will automatically determine the algorithm (RSA, ECC, etc) to use for signing based on the private key's ASN.1 info.  When
       verifying signatures, it only handles the RSA, DSA, or ECDSA signature itself, not the related data to identify the signer and algorithm used in formats such as
       x.509, CMS, and S/MIME.
       A source of random numbers is required for certain signing algorithms, in particular ECDSA and DSA.
       The signing and verify options should only be used if a single file is being signed or verified.
       Hex signatures cannot be verified using openssl.  Instead, use "xxd -r" or similar program to transform the hex signature into a binary signature prior to
       verification.
       The openssl-mac(1) command is preferred over the -hmac, -mac and -macopt command line options.
SEE ALSO
       openssl-mac(1)
HISTORY
       The default digest was changed from MD5 to SHA256 in OpenSSL 1.1.0.  The FIPS-related options were removed in OpenSSL 1.1.0.
       The -engine and -engine_impl options were deprecated in OpenSSL 3.0.
COPYRIGHT
       Copyright 2000-2022 The OpenSSL Project Authors. All Rights Reserved.
       Licensed under the Apache License 2.0 (the "License").  You may not use this file except in compliance with the License.  You can obtain a copy in the file
       LICENSE in the source distribution or at .
3.0.2                                                                           2022-03-16                                                             OPENSSL-DGST(1SSL)