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diff --git a/doc/man1/dgst.pod b/doc/man1/dgst.pod new file mode 100644 index 0000000000..3f1b02ca51 --- /dev/null +++ b/doc/man1/dgst.pod @@ -0,0 +1,240 @@ +=pod + +=head1 NAME + +dgst, sha, sha1, mdc2, ripemd160, sha224, sha256, sha384, sha512, md4, md5, blake2b, blake2s - message digests + +=head1 SYNOPSIS + +B<openssl> B<dgst> +[B<-help>] +[B<-I<digest>>] +[B<-c>] +[B<-d>] +[B<-hex>] +[B<-binary>] +[B<-r>] +[B<-out filename>] +[B<-sign filename>] +[B<-keyform arg>] +[B<-passin arg>] +[B<-verify filename>] +[B<-prverify filename>] +[B<-signature filename>] +[B<-hmac key>] +[B<-fips-fingerprint>] +[B<-engine id>] +[B<-engine_impl>] +[B<file...>] + +B<openssl> +[I<digest>] +[B<...>] + +=head1 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. + +The generic name, B<dgst>, may be used with an option specifying the +algorithm to be used. +The default digest is I<sha256>. +A supported I<digest> name may also be used as the command name. +To see the list of supported algorithms, use the I<list --digest-commands> +command. + +=head1 OPTIONS + +=over 4 + +=item B<-help> + +Print out a usage message. + +=item B<-I<digest>> + +Specifies name of a supported digest to be used. To see the list of +supported digests, use the command I<list --digest-commands>. + +=item B<-c> + +print out the digest in two digit groups separated by colons, only relevant if +B<hex> format output is used. + +=item B<-d> + +print out BIO debugging information. + +=item B<-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 B<-hex>. + +=item B<-binary> + +output the digest or signature in binary form. + +=item B<-r> + +output the digest in the "coreutils" format used by programs like B<sha1sum>. + +=item B<-out filename> + +filename to output to, or standard output by default. + +=item B<-sign filename> + +digitally sign the digest using the private key in "filename". + +=item B<-keyform arg> + +Specifies the key format to sign digest with. The DER, PEM, P12, +and ENGINE formats are supported. + +=item B<-sigopt nm:v> + +Pass options to the signature algorithm during sign or verify operations. +Names and values of these options are algorithm-specific. + + +=item B<-passin arg> + +the private key password source. For more information about the format of B<arg> +see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>. + +=item B<-verify filename> + +verify the signature using the public key in "filename". +The output is either "Verification OK" or "Verification Failure". + +=item B<-prverify filename> + +verify the signature using the private key in "filename". + +=item B<-signature filename> + +the actual signature to verify. + +=item B<-hmac key> + +create a hashed MAC using "key". + +=item B<-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 B<gost-mac> algorithm, +supported by B<ccgost> engine. MAC keys and other options should be set +via B<-macopt> parameter. + +=item B<-macopt nm:v> + +Passes options to MAC algorithm, specified by B<-mac> key. +Following options are supported by both by B<HMAC> and B<gost-mac>: + +=over 8 + +=item B<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. + +=item B<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. + +=back + +=item B<-rand file(s)> + +a file or files containing random data used to seed the random number +generator, or an EGD socket (see L<RAND_egd(3)>). +Multiple files can be specified separated by an OS-dependent character. +The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for +all others. + +=item B<-fips-fingerprint> + +compute HMAC using a specific key +for certain OpenSSL-FIPS operations. + +=item B<-engine id> + +Use engine B<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 or B<-engine_impl> is also +specified. + +=item B<-engine_impl> + +When used with the B<-engine> option, it specifies to also use +engine B<id> for digest operations. + +=item B<file...> + +file or files to digest. If no files are specified then standard input is +used. + +=back + + +=head1 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 + + +=head1 NOTES + +The digest mechanisms that are available will depend on the options +used when building OpenSSL. +The B<list digest-commands> 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, B<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 B<openssl>. Instead, use "xxd -r" +or similar program to transform the hex signature into a binary signature +prior to verification. + +=head1 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 + +=head1 COPYRIGHT + +Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. + +Licensed under the OpenSSL license (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 +L<https://www.openssl.org/source/license.html>. + +=cut |