1=pod 2{- OpenSSL::safe::output_do_not_edit_headers(); -} 3 4=head1 NAME 5 6openssl-dgst - perform digest operations 7 8=head1 SYNOPSIS 9 10B<openssl> B<dgst>|I<digest> 11[B<-I<digest>>] 12[B<-list>] 13[B<-help>] 14[B<-c>] 15[B<-d>] 16[B<-debug>] 17[B<-hex>] 18[B<-binary>] 19[B<-xoflen> I<length>] 20[B<-r>] 21[B<-out> I<filename>] 22[B<-sign> I<filename>|I<uri>] 23[B<-keyform> B<DER>|B<PEM>|B<P12>|B<ENGINE>] 24[B<-passin> I<arg>] 25[B<-verify> I<filename>] 26[B<-prverify> I<filename>] 27[B<-signature> I<filename>] 28[B<-sigopt> I<nm>:I<v>] 29[B<-hmac> I<key>] 30[B<-mac> I<alg>] 31[B<-macopt> I<nm>:I<v>] 32[B<-fips-fingerprint>] 33{- $OpenSSL::safe::opt_engine_synopsis -}{- output_off() if $disabled{"deprecated-3.0"}; "" 34-}[B<-engine_impl> I<id>]{- 35 output_on() if $disabled{"deprecated-3.0"}; "" -} 36{- $OpenSSL::safe::opt_r_synopsis -} 37{- $OpenSSL::safe::opt_provider_synopsis -} 38[I<file> ...] 39 40=head1 DESCRIPTION 41 42This command output the message digest of a supplied file or files 43in hexadecimal, and also generates and verifies digital 44signatures using message digests. 45 46The generic name, B<openssl dgst>, may be used with an option specifying the 47algorithm to be used. 48The default digest is B<sha256>. 49A supported I<digest> name may also be used as the sub-command name. 50To see the list of supported algorithms, use C<openssl list -digest-algorithms> 51 52=head1 OPTIONS 53 54=over 4 55 56=item B<-help> 57 58Print out a usage message. 59 60=item B<-I<digest>> 61 62Specifies name of a supported digest to be used. See option B<-list> below : 63 64=item B<-list> 65 66Prints out a list of supported message digests. 67 68=item B<-c> 69 70Print out the digest in two digit groups separated by colons, only relevant if 71the B<-hex> option is given as well. 72 73=item B<-d>, B<-debug> 74 75Print out BIO debugging information. 76 77=item B<-hex> 78 79Digest is to be output as a hex dump. This is the default case for a "normal" 80digest as opposed to a digital signature. See NOTES below for digital 81signatures using B<-hex>. 82 83=item B<-binary> 84 85Output the digest or signature in binary form. 86 87=item B<-xoflen> I<length> 88 89Set the output length for XOF algorithms, such as B<shake128> and B<shake256>. 90This option is not supported for signing operations. 91 92For OpenSSL providers it is required to set this value for shake algorithms, 93since the previous default values were only set to supply half of the maximum 94security strength. 95 96To ensure the maximum security strength of 128 bits, the xoflen for B<shake128> 97should be set to at least 32 (bytes). For compatibility with previous versions 98of OpenSSL, it may be set to 16, resulting in a security strength of only 64 99bits. 100 101To ensure the maximum security strength of 256 bits, the xoflen for B<shake256> 102should be set to at least 64 (bytes). For compatibility with previous versions 103of OpenSSL, it may be set to 32, resulting in a security strength of only 128 104bits. 105 106=item B<-r> 107 108=for openssl foreign manual sha1sum(1) 109 110Output the digest in the "coreutils" format, including newlines. 111Used by programs like L<sha1sum(1)>. 112 113=item B<-out> I<filename> 114 115Filename to output to, or standard output by default. 116 117=item B<-sign> I<filename>|I<uri> 118 119Digitally sign the digest using the given private key. 120 121Note that for algorithms that only support one-shot signing 122(such as Ed25519, ED448, ML-DSA-44, ML-DSA-65 andML-DSA-87) the digest must not 123be set. For these algorithms the input is buffered (and not digested) before 124signing. For these algorithms, if the input is larger than 16MB an error 125will occur. 126 127=item B<-keyform> B<DER>|B<PEM>|B<P12>|B<ENGINE> 128 129The format of the key to sign with; unspecified by default. 130See L<openssl-format-options(1)> for details. 131 132=item B<-sigopt> I<nm>:I<v> 133 134Pass options to the signature algorithm during sign or verify operations. 135Names and values of these options are algorithm-specific and documented 136in L<provider-signature(7)/Signature parameters>. 137 138=item B<-passin> I<arg> 139 140The private key password source. For more information about the format of I<arg> 141see L<openssl-passphrase-options(1)>. 142 143=item B<-verify> I<filename> 144 145Verify the signature using the public key in "filename". 146The output is either "Verified OK" or "Verification Failure". 147 148=item B<-prverify> I<filename> 149 150Verify the signature using the private key in "filename". 151 152=item B<-signature> I<filename> 153 154The actual signature to verify. 155 156=item B<-hmac> I<key> 157 158Create a hashed MAC using "key". 159 160The L<openssl-mac(1)> command should be preferred to using this command line 161option. 162 163=item B<-mac> I<alg> 164 165Create MAC (keyed Message Authentication Code). The most popular MAC 166algorithm is HMAC (hash-based MAC), but there are other MAC algorithms 167which are not based on hash, for instance B<gost-mac> algorithm, 168supported by the B<gost> engine. MAC keys and other options should be set 169via B<-macopt> parameter. 170 171The L<openssl-mac(1)> command should be preferred to using this command line 172option. 173 174=item B<-macopt> I<nm>:I<v> 175 176Passes options to MAC algorithm, specified by B<-mac> key. 177Following options are supported by both by B<HMAC> and B<gost-mac>: 178 179=over 4 180 181=item B<key>:I<string> 182 183Specifies MAC key as alphanumeric string (use if key contain printable 184characters only). String length must conform to any restrictions of 185the MAC algorithm for example exactly 32 chars for gost-mac. 186 187=item B<hexkey>:I<string> 188 189Specifies MAC key in hexadecimal form (two hex digits per byte). 190Key length must conform to any restrictions of the MAC algorithm 191for example exactly 32 chars for gost-mac. 192 193=back 194 195The L<openssl-mac(1)> command should be preferred to using this command line 196option. 197 198=item B<-fips-fingerprint> 199 200Compute HMAC using a specific key for certain OpenSSL-FIPS operations. 201 202{- $OpenSSL::safe::opt_r_item -} 203 204{- $OpenSSL::safe::opt_engine_item -} 205{- output_off() if $disabled{"deprecated-3.0"}; "" -} 206The engine is not used for digests unless the B<-engine_impl> option is 207used or it is configured to do so, see L<config(5)/Engine Configuration Module>. 208 209=item B<-engine_impl> I<id> 210 211When used with the B<-engine> option, it specifies to also use 212engine I<id> for digest operations. 213 214{- output_on() if $disabled{"deprecated-3.0"}; "" -} 215{- $OpenSSL::safe::opt_provider_item -} 216 217=item I<file> ... 218 219File or files to digest. If no files are specified then standard input is 220used. 221 222=back 223 224 225=head1 EXAMPLES 226 227To create a hex-encoded message digest of a file: 228 229 openssl dgst -md5 -hex file.txt 230 or 231 openssl md5 file.txt 232 233To sign a file using SHA-256 with binary file output: 234 235 openssl dgst -sha256 -sign privatekey.pem -out signature.sign file.txt 236 or 237 openssl sha256 -sign privatekey.pem -out signature.sign file.txt 238 239To verify a signature: 240 241 openssl dgst -sha256 -verify publickey.pem \ 242 -signature signature.sign \ 243 file.txt 244 245 246=head1 NOTES 247 248The digest mechanisms that are available will depend on the options 249used when building OpenSSL. 250The C<openssl list -digest-algorithms> command can be used to list them. 251 252New or agile applications should use probably use SHA-256. Other digests, 253particularly SHA-1 and MD5, are still widely used for interoperating 254with existing formats and protocols. 255 256When signing a file, this command will automatically determine the algorithm 257(RSA, ECC, etc) to use for signing based on the private key's ASN.1 info. 258When verifying signatures, it only handles the RSA, DSA, or ECDSA signature 259itself, not the related data to identify the signer and algorithm used in 260formats such as x.509, CMS, and S/MIME. 261 262A source of random numbers is required for certain signing algorithms, in 263particular ECDSA and DSA. 264 265The signing and verify options should only be used if a single file is 266being signed or verified. 267 268Hex signatures cannot be verified using B<openssl>. Instead, use "xxd -r" 269or similar program to transform the hex signature into a binary signature 270prior to verification. 271 272The L<openssl-mac(1)> command is preferred over the B<-hmac>, B<-mac> and 273B<-macopt> command line options. 274 275=head1 SEE ALSO 276 277L<openssl-mac(1)> 278 279=head1 HISTORY 280 281The default digest was changed from MD5 to SHA256 in OpenSSL 1.1.0. 282The FIPS-related options were removed in OpenSSL 1.1.0. 283 284The B<-engine> and B<-engine_impl> options were deprecated in OpenSSL 3.0. 285 286=head1 COPYRIGHT 287 288Copyright 2000-2025 The OpenSSL Project Authors. All Rights Reserved. 289 290Licensed under the Apache License 2.0 (the "License"). You may not use 291this file except in compliance with the License. You can obtain a copy 292in the file LICENSE in the source distribution or at 293L<https://www.openssl.org/source/license.html>. 294 295=cut 296