2 {- OpenSSL::safe::output_do_not_edit_headers(); -}
6 openssl-kdf - perform Key Derivation Function operations
15 [B<-kdfopt> I<nm>:I<v>]
19 {- $OpenSSL::safe::opt_provider_synopsis -}
24 The key derivation functions generate a derived key from either a secret or
33 Print a usage message.
35 =item B<-keylen> I<num>
37 The output size of the derived key. This field is required.
39 =item B<-out> I<filename>
41 Filename to output to, or standard output by default.
45 Output the derived key in binary form. Uses hexadecimal text format if not specified.
47 =item B<-cipher> I<name>
49 Specify the cipher to be used by the KDF.
50 Not all KDFs require a cipher and it is an error to use this option in such
53 =item B<-digest> I<name>
55 Specify the digest to be used by the KDF.
56 Not all KDFs require a digest and it is an error to use this option in such
58 To see the list of supported digests, use C<openssl list -digest-commands>.
62 Specify the MAC to be used by the KDF.
63 Not all KDFs require a MAC and it is an error to use this option in such
66 =item B<-kdfopt> I<nm>:I<v>
68 Passes options to the KDF algorithm.
69 A comprehensive list of parameters can be found in the EVP_KDF_CTX
70 implementation documentation.
71 Common parameter names used by EVP_KDF_CTX_set_params() are:
75 =item B<key:>I<string>
77 Specifies the secret key as an alphanumeric string (use if the key contains
78 printable characters only).
79 The string length must conform to any restrictions of the KDF algorithm.
80 A key must be specified for most KDF algorithms.
82 =item B<hexkey:>I<string>
84 Specifies the secret key in hexadecimal form (two hex digits per byte).
85 The key length must conform to any restrictions of the KDF algorithm.
86 A key must be specified for most KDF algorithms.
88 =item B<pass:>I<string>
90 Specifies the password as an alphanumeric string (use if the password contains
91 printable characters only).
92 The password must be specified for PBKDF2 and scrypt.
94 =item B<hexpass:>I<string>
96 Specifies the password in hexadecimal form (two hex digits per byte).
97 The password must be specified for PBKDF2 and scrypt.
99 =item B<digest:>I<string>
101 This option is identical to the B<-digest> option.
103 =item B<cipher:>I<string>
105 This option is identical to the B<-cipher> option.
107 =item B<mac:>I<string>
109 This option is identical to the B<-mac> option.
113 {- $OpenSSL::safe::opt_provider_item -}
117 Specifies the name of a supported KDF algorithm which will be used.
118 The supported algorithms names include TLS1-PRF, HKDF, SSKDF, PBKDF2,
119 SSHKDF, X942KDF-ASN1, X942KDF-CONCAT, X963KDF and SCRYPT.
125 Use TLS1-PRF to create a hex-encoded derived key from a secret key and seed:
127 openssl kdf -keylen 16 -kdfopt digest:SHA2-256 -kdfopt key:secret \
128 -kdfopt seed:seed TLS1-PRF
130 Use HKDF to create a hex-encoded derived key from a secret key, salt and info:
132 openssl kdf -keylen 10 -kdfopt digest:SHA2-256 -kdfopt key:secret \
133 -kdfopt salt:salt -kdfopt info:label HKDF
135 Use SSKDF with KMAC to create a hex-encoded derived key from a secret key, salt and info:
137 openssl kdf -keylen 64 -kdfopt mac:KMAC-128 -kdfopt maclen:20 \
138 -kdfopt hexkey:b74a149a161545 -kdfopt hexinfo:348a37a2 \
139 -kdfopt hexsalt:3638271ccd68a2 SSKDF
141 Use SSKDF with HMAC to create a hex-encoded derived key from a secret key, salt and info:
143 openssl kdf -keylen 16 -kdfopt mac:HMAC -kdfopt digest:SHA2-256 \
144 -kdfopt hexkey:b74a149a -kdfopt hexinfo:348a37a2 \
145 -kdfopt hexsalt:3638271c SSKDF
147 Use SSKDF with Hash to create a hex-encoded derived key from a secret key, salt and info:
149 openssl kdf -keylen 14 -kdfopt digest:SHA2-256 \
150 -kdfopt hexkey:6dbdc23f045488 \
151 -kdfopt hexinfo:a1b2c3d4 SSKDF
153 Use SSHKDF to create a hex-encoded derived key from a secret key, hash and session_id:
155 openssl kdf -keylen 16 -kdfopt digest:SHA2-256 \
156 -kdfopt hexkey:0102030405 \
157 -kdfopt hexxcghash:06090A \
158 -kdfopt hexsession_id:01020304 \
159 -kdfopt type:A SSHKDF
161 Use PBKDF2 to create a hex-encoded derived key from a password and salt:
163 openssl kdf -keylen 32 -kdfopt digest:SHA256 -kdfopt pass:password \
164 -kdfopt salt:salt -kdfopt iter:2 PBKDF2
166 Use scrypt to create a hex-encoded derived key from a password and salt:
168 openssl kdf -keylen 64 -kdfopt pass:password -kdfopt salt:NaCl \
169 -kdfopt N:1024 -kdfopt r:8 -kdfopt p:16 \
170 -kdfopt maxmem_bytes:10485760 SCRYPT
174 The KDF mechanisms that are available will depend on the options
175 used when building OpenSSL.
180 L<openssl-pkeyutl(1)>,
182 L<EVP_KDF-SCRYPT(7)>,
183 L<EVP_KDF-TLS1_PRF(7)>,
184 L<EVP_KDF-PBKDF2(7)>,
187 L<EVP_KDF-SSHKDF(7)>,
188 L<EVP_KDF-X942-ASN1(7)>,
189 L<EVP_KDF-X942-CONCAT(7)>,
198 Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
200 Licensed under the Apache License 2.0 (the "License"). You may not use
201 this file except in compliance with the License. You can obtain a copy
202 in the file LICENSE in the source distribution or at
203 L<https://www.openssl.org/source/license.html>.