dgst(1ssl)


NAME

   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
       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 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
       algorithm, 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
       number generator, or an EGD socket (see RAND_egd(3)).  Multiple
       files can be specified separated by a OS-dependent character.  The
       separator 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
       operations.

   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
   signature prior to verification.





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