dgst, md5, md4, md2, sha1, sha, mdc2, ripemd160 - message digests
openssl dgst [-md5|-md4|-md2|-sha1|-sha|-mdc2|-ripemd160|-dss1] [-c] [-d] [-hex] [-binary] [-hmac arg] [-non-fips-allow] [-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...]
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.
-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. -hmac arg set the HMAC key to arg. -non-fips-allow allow use of non FIPS digest. -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(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. file... file or files to digest. If no files are specified then standard input is used.
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.