md2(3)

NAME

       openssl-dgst, dgst, sha, sha1, mdc2, ripemd160, sha224, sha256, sha384,
       sha512, md2, md4, md5, dss1 - message digests

SYNOPSIS

       openssl dgst
       [-sha|-sha1|-mdc2|-ripemd160|-sha224|-sha256|-sha384|-sha512|-md2|-md4|-md5|-dss1]
       [-c] [-d] [-hex] [-binary] [-r] [-non-fips-allow] [-out filename]
       [-sign filename] [-keyform arg] [-passin arg] [-verify filename]
       [-prverify filename] [-signature filename] [-hmac key]
       [-non-fips-allow] [-fips-fingerprint] [file...]

       openssl [digest] [...]

DESCRIPTION

       The digest functions output the message digest of a supplied file or
       files in hexadecimal.  The digest functions also generate and verify
       digital signatures using message digests.

OPTIONS

       -c  print out the digest in two digit groups separated by colons, only
           relevant if hex format output is used.

       -d  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.

       -r  output the digest in the "coreutils" format used by programs like
           sha1sum.

       -non-fips-allow
           Allow use of non FIPS digest when in FIPS mode.  This has no effect
           when not in FIPS mode.

       -out filename
           filename to output to, or standard output by default.

       -sign filename
           digitally sign the digest using the private key in "filename".

       -keyform arg
           Specifies the key format to sign digest with. The DER, PEM, P12,
           and ENGINE formats are supported.

       -engine id
           Use engine id for operations (including private key storage).  This
           engine is not used as source for digest algorithms, unless it is
           also specified in the configuration file.

       -sigopt nm:v
           Pass options to the signature algorithm during sign or verify oper-
           ations.  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 the PASS PHRASE ARGUMENTS section in openssl(1).

       -verify filename
           verify the signature using the the public key in "filename".  The
           output is either "Verification OK" or "Verification Failure".

       -prverify filename
           verify the signature using the  the private key in "filename".

       -signature filename
           the actual signature to verify.

       -hmac key
           create a hashed MAC using "key".

       -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 algo-
           rithm, supported by ccgost engine. MAC keys and other options
           should be set via -macopt parameter.

       -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 alphnumeric 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.

       -rand file(s)
           a file or files containing random data used to seed the random num-
           ber generator, or an EGD socket (see RAND_egd(3)).  Multiple files
           can be specified separated by a OS-dependent character.  The sepa-
           rator is ; for MS-Windows, , for OpenVMS, and : for all others.

       -non-fips-allow
           enable use of non-FIPS algorithms such as MD5 even in FIPS mode.

       -fips-fingerprint
           compute HMAC using a specific key for certain OpenSSL-FIPS opera-
           tions.

       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

       To sign a file using SHA-256 with binary file output:
        openssl dgst -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 of choice for all new applications is SHA1. Other digests
       are however still widely used.

       When signing a file, dgst 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 signa-
       ture prior to verification.

1.0.2t                            2019-09-10                           DGST(1)
See also dgst(1)
See also dss1(1)
See also md4(1)
See also md5(1)
See also mdc2(1)
See also openssl-dgst(1)
See also ripemd160(1)
See also sha(1)
See also sha1(1)
See also sha224(1)
See also sha256(1)
See also sha384(1)
See also sha512(1)