4 {- join("\n", @autowarntext) -}
10 openssl-pkeyutl - public key algorithm utility
18 [B<-digest> I<algorithm>]
22 [B<-keyform> B<DER>|B<PEM>|B<ENGINE>]
25 [B<-peerform> B<DER>|B<PEM>|B<ENGINE>]
35 [B<-kdf> I<algorithm>]
36 [B<-kdflen> I<length>]
37 [B<-pkeyopt> I<opt>:I<value>]
38 [B<-pkeyopt_passin> I<opt>[:I<passarg>]]
43 {- $OpenSSL::safe::opt_r_synopsis -}
45 =for openssl ifdef engine engine_impl
49 This command can be used to perform low level public key
50 operations using any supported algorithm.
58 Print out a usage message.
60 =item B<-in> I<filename>
62 This specifies the input filename to read data from or standard input
63 if this option is not specified.
67 This indicates that the input data is raw data, which is not hashed by any
68 message digest algorithm. The user can specify a digest algorithm by using
69 the B<-digest> option. This option can only be used with B<-sign> and
70 B<-verify> and must be used with the Ed25519 and Ed448 algorithms.
72 =item B<-digest> I<algorithm>
74 This specifies the digest algorithm which is used to hash the input data before
75 signing or verifying it with the input key. This option could be omitted if the
76 signature algorithm does not require one (for instance, EdDSA). If this option
77 is omitted but the signature algorithm requires one, a default value will be
78 used. For signature algorithms like RSA, DSA and ECDSA, SHA-256 will be the
79 default digest algorithm. For SM2, it will be SM3. If this option is present,
80 then the B<-rawin> option must be also specified.
82 =item B<-out> I<filename>
84 Specifies the output filename to write to or standard output by
87 =item B<-sigfile> I<file>
89 Signature file, required for B<-verify> operations only
91 =item B<-inkey> I<file>
93 The input key file, by default it should be a private key.
95 =item B<-keyform> B<DER>|B<PEM>|B<ENGINE>
97 The key format; the default is B<PEM>.
98 See L<openssl(1)/Format Options> for details.
100 =item B<-passin> I<arg>
102 The input key password source. For more information about the format of I<arg>
103 see L<openssl(1)/Pass Phrase Options>.
105 =item B<-peerkey> I<file>
107 The peer key file, used by key derivation (agreement) operations.
109 =item B<-peerform> B<DER>|B<PEM>|B<ENGINE>
111 The peer key format; the default is B<PEM>.
112 See L<openssl(1)/Format Options> for details.
116 The input file is a public key.
120 The input is a certificate containing a public key.
124 Reverse the order of the input buffer. This is useful for some libraries
125 (such as CryptoAPI) which represent the buffer in little endian format.
129 Sign the input data (which must be a hash) and output the signed result. This
130 requires a private key.
134 Verify the input data (which must be a hash) against the signature file and
135 indicate if the verification succeeded or failed.
137 =item B<-verifyrecover>
139 Verify the input data (which must be a hash) and output the recovered data.
143 Encrypt the input data using a public key.
147 Decrypt the input data using a private key.
151 Derive a shared secret using the peer key.
153 =item B<-kdf> I<algorithm>
155 Use key derivation function I<algorithm>. The supported algorithms are
156 at present B<TLS1-PRF> and B<HKDF>.
157 Note: additional parameters and the KDF output length will normally have to be
158 set for this to work.
159 See L<EVP_PKEY_CTX_set_hkdf_md(3)> and L<EVP_PKEY_CTX_set_tls1_prf_md(3)>
160 for the supported string parameters of each algorithm.
162 =item B<-kdflen> I<length>
164 Set the output length for KDF.
166 =item B<-pkeyopt> I<opt>:I<value>
168 Public key options specified as opt:value. See NOTES below for more details.
170 =item B<-pkeyopt_passin> I<opt>[:I<passarg>]
172 Allows reading a public key option I<opt> from stdin or a password source.
173 If only I<opt> is specified, the user will be prompted to enter a password on
174 stdin. Alternatively, I<passarg> can be specified which can be any value
175 supported by L<openssl(1)/Pass phrase options>.
179 hex dump the output data.
183 Parse the ASN.1 output data, this is useful when combined with the
184 B<-verifyrecover> option when an ASN1 structure is signed.
186 =item B<-engine> I<id>
188 Specifying an engine (by its unique I<id> string) will cause this command
189 to attempt to obtain a functional reference to the specified engine,
190 thus initialising it if needed. The engine will then be set as the default
191 for all available algorithms.
193 =item B<-engine_impl>
195 When used with the B<-engine> option, it specifies to also use
196 engine I<id> for crypto operations.
198 {- $OpenSSL::safe::opt_r_item -}
204 The operations and options supported vary according to the key algorithm
205 and its implementation. The OpenSSL operations and options are indicated below.
207 Unless otherwise mentioned all algorithms support the B<digest:>I<alg> option
208 which specifies the digest in use for sign, verify and verifyrecover operations.
209 The value I<alg> should represent a digest name as used in the
210 EVP_get_digestbyname() function for example B<sha1>. This value is not used to
211 hash the input data. It is used (by some algorithms) for sanity-checking the
212 lengths of data passed in and for creating the structures that make up the
213 signature (e.g. B<DigestInfo> in RSASSA PKCS#1 v1.5 signatures).
215 This command does not hash the input data (except where -rawin is used) but
216 rather it will use the data directly as input to the signature algorithm.
217 Depending on the key type, signature type, and mode of padding, the maximum
218 acceptable lengths of input data differ. The signed data can't be longer than
219 the key modulus with RSA. In case of ECDSA and DSA the data shouldn't be longer
220 than the field size, otherwise it will be silently truncated to the field size.
221 In any event the input size must not be larger than the largest supported digest
224 In other words, if the value of digest is B<sha1> the input should be the 20
225 bytes long binary encoding of the SHA-1 hash function output.
229 The RSA algorithm generally supports the encrypt, decrypt, sign,
230 verify and verifyrecover operations. However, some padding modes
231 support only a subset of these operations. The following additional
232 B<pkeyopt> values are supported:
236 =item B<rsa_padding_mode:>I<mode>
238 This sets the RSA padding mode. Acceptable values for I<mode> are B<pkcs1> for
239 PKCS#1 padding, B<sslv23> for SSLv23 padding, B<none> for no padding, B<oaep>
240 for B<OAEP> mode, B<x931> for X9.31 mode and B<pss> for PSS.
242 In PKCS#1 padding if the message digest is not set then the supplied data is
243 signed or verified directly instead of using a B<DigestInfo> structure. If a
244 digest is set then the a B<DigestInfo> structure is used and its the length
245 must correspond to the digest type.
247 For B<oaep> mode only encryption and decryption is supported.
249 For B<x931> if the digest type is set it is used to format the block data
250 otherwise the first byte is used to specify the X9.31 digest ID. Sign,
251 verify and verifyrecover are can be performed in this mode.
253 For B<pss> mode only sign and verify are supported and the digest type must be
256 =item B<rsa_pss_saltlen:>I<len>
258 For B<pss> mode only this option specifies the salt length. Three special
259 values are supported: B<digest> sets the salt length to the digest length,
260 B<max> sets the salt length to the maximum permissible value. When verifying
261 B<auto> causes the salt length to be automatically determined based on the
262 B<PSS> block structure.
264 =item B<rsa_mgf1_md:>I<digest>
266 For PSS and OAEP padding sets the MGF1 digest. If the MGF1 digest is not
267 explicitly set in PSS mode then the signing digest is used.
271 =head1 RSA-PSS ALGORITHM
273 The RSA-PSS algorithm is a restricted version of the RSA algorithm which only
274 supports the sign and verify operations with PSS padding. The following
275 additional B<-pkeyopt> values are supported:
279 =item B<rsa_padding_mode:>I<mode>, B<rsa_pss_saltlen:>I<len>,
280 B<rsa_mgf1_md:>I<digest>
282 These have the same meaning as the B<RSA> algorithm with some additional
283 restrictions. The padding mode can only be set to B<pss> which is the
286 If the key has parameter restrictions than the digest, MGF1
287 digest and salt length are set to the values specified in the parameters.
288 The digest and MG cannot be changed and the salt length cannot be set to a
289 value less than the minimum restriction.
295 The DSA algorithm supports signing and verification operations only. Currently
296 there are no additional B<-pkeyopt> options other than B<digest>. The SHA1
297 digest is assumed by default.
301 The DH algorithm only supports the derivation operation and no additional
306 The EC algorithm supports sign, verify and derive operations. The sign and
307 verify operations use ECDSA and derive uses ECDH. SHA1 is assumed by default for
308 the B<-pkeyopt> B<digest> option.
310 =head1 X25519 AND X448 ALGORITHMS
312 The X25519 and X448 algorithms support key derivation only. Currently there are
313 no additional options.
315 =head1 ED25519 AND ED448 ALGORITHMS
317 These algorithms only support signing and verifying. OpenSSL only implements the
318 "pure" variants of these algorithms so raw data can be passed directly to them
319 without hashing them first. The option B<-rawin> must be used with these
320 algorithms with no B<-digest> specified. Additionally OpenSSL only supports
321 "oneshot" operation with these algorithms. This means that the entire file to
322 be signed/verified must be read into memory before processing it. Signing or
323 Verifying very large files should be avoided. Additionally the size of the file
324 must be known for this to work. If the size of the file cannot be determined
325 (for example if the input is stdin) then the sign or verify operation will fail.
329 The SM2 algorithm supports sign, verify, encrypt and decrypt operations. For
330 the sign and verify operations, SM2 requires an ID string to be passed in. The
331 following B<-pkeyopt> value is supported:
335 =item B<sm2_id:>I<string>
337 This sets the ID string used in SM2 sign or verify operations. While verifying
338 an SM2 signature, the ID string must be the same one used when signing the data.
339 Otherwise the verification will fail.
341 =item B<sm2_hex_id:>I<hex_string>
343 This sets the ID string used in SM2 sign or verify operations. While verifying
344 an SM2 signature, the ID string must be the same one used when signing the data.
345 Otherwise the verification will fail. The ID string provided with this option
346 should be a valid hexadecimal value.
352 Sign some data using a private key:
354 openssl pkeyutl -sign -in file -inkey key.pem -out sig
356 Recover the signed data (e.g. if an RSA key is used):
358 openssl pkeyutl -verifyrecover -in sig -inkey key.pem
360 Verify the signature (e.g. a DSA key):
362 openssl pkeyutl -verify -in file -sigfile sig -inkey key.pem
364 Sign data using a message digest value (this is currently only valid for RSA):
366 openssl pkeyutl -sign -in file -inkey key.pem -out sig -pkeyopt digest:sha256
368 Derive a shared secret value:
370 openssl pkeyutl -derive -inkey key.pem -peerkey pubkey.pem -out secret
372 Hexdump 48 bytes of TLS1 PRF using digest B<SHA256> and shared secret and
373 seed consisting of the single byte 0xFF:
375 openssl pkeyutl -kdf TLS1-PRF -kdflen 48 -pkeyopt md:SHA256 \
376 -pkeyopt hexsecret:ff -pkeyopt hexseed:ff -hexdump
378 Derive a key using B<scrypt> where the password is read from command line:
380 openssl pkeyutl -kdf scrypt -kdflen 16 -pkeyopt_passin pass \
381 -pkeyopt hexsalt:aabbcc -pkeyopt N:16384 -pkeyopt r:8 -pkeyopt p:1
383 Derive using the same algorithm, but read key from environment variable MYPASS:
385 openssl pkeyutl -kdf scrypt -kdflen 16 -pkeyopt_passin pass:env:MYPASS \
386 -pkeyopt hexsalt:aabbcc -pkeyopt N:16384 -pkeyopt r:8 -pkeyopt p:1
388 Sign some data using an L<SM2(7)> private key and a specific ID:
390 openssl pkeyutl -sign -in file -inkey sm2.key -out sig -rawin -digest sm3 \
391 -pkeyopt sm2_id:someid
393 Verify some data using an L<SM2(7)> certificate and a specific ID:
395 openssl pkeyutl -verify -certin -in file -inkey sm2.cert -sigfile sig \
396 -rawin -digest sm3 -pkeyopt sm2_id:someid
401 L<openssl-genpkey(1)>,
406 L<openssl-genrsa(1)>,
408 L<EVP_PKEY_CTX_set_hkdf_md(3)>,
409 L<EVP_PKEY_CTX_set_tls1_prf_md(3)>,
414 Copyright 2006-2019 The OpenSSL Project Authors. All Rights Reserved.
416 Licensed under the Apache License 2.0 (the "License"). You may not use
417 this file except in compliance with the License. You can obtain a copy
418 in the file LICENSE in the source distribution or at
419 L<https://www.openssl.org/source/license.html>.