- NAME
- SYNOPSIS
- DESCRIPTION
- OPTIONS
- NOTES

# NAME

dgst, md5, md4, md2, sha1, sha, mdc2, ripemd160 - message digests

# SYNOPSIS

openssl dgst [-md5|-md4|-md2|-sha1|-sha|-mdc2|-ripemd160|-dss1] [-c] [-d] [-hex] [-binary] [-out filename] [-sign filename] [-keyform arg] [-passin arg] [-verify filename] [-prverify filename] [-signature filename] [-hmac key] [file...]

[md5|md4|md2|sha1|sha|mdc2|ripemd160] [-c] [-d] [file...]

# DESCRIPTION

The digest functions output the message digest of a supplied file or files in hexadecimal form. They can also be used for digital signing and verification.

# 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.

-binary

  output the digest or signature in binary form.

-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. Only PEM and ENGINE formats are supported by the dgst command.

-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.

-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). Multiple files can be specified separated by a OS-dependent character. The separator is ; for MS-Windows, , for OpenVMS, and : for all others.

file...

  file or files to digest. If no files are specified then standard input is used.

# NOTES

The digest of choice for all new applications is SHA1. Other digests are however still widely used.

If you wish to sign or verify data using the DSA algorithm then the dss1 digest must be used.

A source of random numbers is required for certain signing algorithms, in particular DSA.

The signing and verify options should only be used if a single file is being signed or verified.