5 openssl-dgst - perform digest operations
18 [B<-sign> I<filename>]
21 [B<-verify> I<filename>]
22 [B<-prverify> I<filename>]
23 [B<-signature> I<filename>]
24 [B<-sigopt> I<nm>:I<v>]
26 [B<-fips-fingerprint>]
32 B<openssl> I<digest> [B<...>]
36 The digest functions output the message digest of a supplied file or files
37 in hexadecimal. The digest functions also generate and verify digital
38 signatures using message digests.
40 The generic name, B<dgst>, may be used with an option specifying the
42 The default digest is B<sha256>.
43 A supported I<digest> name may also be used as the command name.
44 To see the list of supported algorithms, use the I<list --digest-commands>
53 Print out a usage message.
57 Specifies name of a supported digest to be used. To see the list of
58 supported digests, use the command C<list --digest-commands>.
62 Print out the digest in two digit groups separated by colons, only relevant if
63 the B<-hex> option is given as well.
67 Print out BIO debugging information.
71 Digest is to be output as a hex dump. This is the default case for a "normal"
72 digest as opposed to a digital signature. See NOTES below for digital
73 signatures using B<-hex>.
77 Output the digest or signature in binary form.
81 Output the digest in the "coreutils" format, including newlines.
82 Used by programs like B<sha1sum>.
84 =item B<-out> I<filename>
86 Filename to output to, or standard output by default.
88 =item B<-sign> I<filename>
90 Digitally sign the digest using the private key in "filename". Note this option
91 does not support Ed25519 or Ed448 private keys. Use the B<pkeyutl> command
94 =item B<-keyform> I<arg>
96 Specifies the key format to sign digest with. The DER, PEM, P12,
97 and ENGINE formats are supported.
99 =item B<-sigopt> I<nm>:I<v>
101 Pass options to the signature algorithm during sign or verify operations.
102 Names and values of these options are algorithm-specific.
104 =item B<-passin> I<arg>
106 The private key password source. For more information about the format of I<arg>
107 see L<openssl(1)/Pass phrase options>.
109 =item B<-verify> I<filename>
111 Verify the signature using the public key in "filename".
112 The output is either "Verification OK" or "Verification Failure".
114 =item B<-prverify> I<filename>
116 Verify the signature using the private key in "filename".
118 =item B<-signature> I<filename>
120 The actual signature to verify.
122 =item B<-hmac> I<key>
124 Create a hashed MAC using "key".
126 The L<openssl-mac(1)> command should be preferred to using this command line
131 Create MAC (keyed Message Authentication Code). The most popular MAC
132 algorithm is HMAC (hash-based MAC), but there are other MAC algorithms
133 which are not based on hash, for instance B<gost-mac> algorithm,
134 supported by B<ccgost> engine. MAC keys and other options should be set
135 via B<-macopt> parameter.
137 The L<openssl-mac(1)> command should be preferred to using this command line
140 =item B<-macopt> I<nm>:I<v>
142 Passes options to MAC algorithm, specified by B<-mac> key.
143 Following options are supported by both by B<HMAC> and B<gost-mac>:
147 =item B<key>:I<string>
149 Specifies MAC key as alphanumeric string (use if key contain printable
150 characters only). String length must conform to any restrictions of
151 the MAC algorithm for example exactly 32 chars for gost-mac.
153 =item B<hexkey>:I<string>
155 Specifies MAC key in hexadecimal form (two hex digits per byte).
156 Key length must conform to any restrictions of the MAC algorithm
157 for example exactly 32 chars for gost-mac.
161 The L<openssl-mac(1)> command should be preferred to using this command line
164 =item B<-rand> I<files>
166 The files containing random data used to seed the random number generator.
167 Multiple files can be specified separated by an OS-dependent character.
168 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
171 =item B<-writerand> I<file>
173 Writes random data to the specified I<file> upon exit.
174 This can be used with a subsequent B<-rand> flag.
176 =item B<-fips-fingerprint>
178 Compute HMAC using a specific key for certain OpenSSL-FIPS operations.
180 =item B<-engine> I<id>
182 Use engine I<id> for operations (including private key storage).
183 This engine is not used as source for digest algorithms, unless it is
184 also specified in the configuration file or B<-engine_impl> is also
187 =item B<-engine_impl>
189 When used with the B<-engine> option, it specifies to also use
190 engine I<id> for digest operations.
194 File or files to digest. If no files are specified then standard input is
202 To create a hex-encoded message digest of a file:
203 openssl dgst -md5 -hex file.txt
205 To sign a file using SHA-256 with binary file output:
206 openssl dgst -sha256 -sign privatekey.pem -out signature.sign file.txt
208 To verify a signature:
209 openssl dgst -sha256 -verify publickey.pem \
210 -signature signature.sign \
216 The digest mechanisms that are available will depend on the options
217 used when building OpenSSL.
218 The B<list digest-commands> command can be used to list them.
220 New or agile applications should use probably use SHA-256. Other digests,
221 particularly SHA-1 and MD5, are still widely used for interoperating
222 with existing formats and protocols.
224 When signing a file, B<dgst> will automatically determine the algorithm
225 (RSA, ECC, etc) to use for signing based on the private key's ASN.1 info.
226 When verifying signatures, it only handles the RSA, DSA, or ECDSA signature
227 itself, not the related data to identify the signer and algorithm used in
228 formats such as x.509, CMS, and S/MIME.
230 A source of random numbers is required for certain signing algorithms, in
231 particular ECDSA and DSA.
233 The signing and verify options should only be used if a single file is
234 being signed or verified.
236 Hex signatures cannot be verified using B<openssl>. Instead, use "xxd -r"
237 or similar program to transform the hex signature into a binary signature
238 prior to verification.
240 The L<openssl-mac(1)> command is preferred over the B<-hmac>, B<-mac> and
241 B<-macopt> command line options.
249 The default digest was changed from MD5 to SHA256 in OpenSSL 1.1.0.
250 The FIPS-related options were removed in OpenSSL 1.1.0.
254 Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.
256 Licensed under the Apache License 2.0 (the "License"). You may not use
257 this file except in compliance with the License. You can obtain a copy
258 in the file LICENSE in the source distribution or at
259 L<https://www.openssl.org/source/license.html>.