doc/man1/pkeyutl.pod - third_party/openssl - Git at Google

 =pod

 =head1 NAME

 pkeyutl - public key algorithm utility

 =head1 SYNOPSIS

 B<openssl> B<pkeyutl>
 [B<-help>]
 [B<-in file>]
 [B<-out file>]
 [B<-sigfile file>]
 [B<-inkey file>]
 [B<-keyform PEM|DER|ENGINE>]
 [B<-passin arg>]
 [B<-peerkey file>]
 [B<-peerform PEM|DER|ENGINE>]
 [B<-pubin>]
 [B<-certin>]
 [B<-rev>]
 [B<-sign>]
 [B<-verify>]
 [B<-verifyrecover>]
 [B<-encrypt>]
 [B<-decrypt>]
 [B<-derive>]
 [B<-kdf algorithm>]
 [B<-kdflen length>]
 [B<-pkeyopt opt:value>]
 [B<-hexdump>]
 [B<-asn1parse>]
 [B<-engine id>]
 [B<-engine_impl>]

 =head1 DESCRIPTION

 The B<pkeyutl> command can be used to perform public key operations using
 any supported algorithm.

 =head1 OPTIONS

 =over 4

 =item B<-help>

 Print out a usage message.

 =item B<-in filename>

 This specifies the input filename to read data from or standard input
 if this option is not specified.

 =item B<-out filename>

 specifies the output filename to write to or standard output by
 default.

 =item B<-sigfile file>

 Signature file, required for B<verify> operations only

 =item B<-inkey file>

 the input key file, by default it should be a private key.

 =item B<-keyform PEM|DER|ENGINE>

 the key format PEM, DER or ENGINE. Default is PEM.

 =item B<-passin arg>

 the input 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<-peerkey file>

 the peer key file, used by key derivation (agreement) operations.

 =item B<-peerform PEM|DER|ENGINE>

 the peer key format PEM, DER or ENGINE. Default is PEM.

 =item B<-pubin>

 the input file is a public key.

 =item B<-certin>

 the input is a certificate containing a public key.

 =item B<-rev>

 reverse the order of the input buffer. This is useful for some libraries
 (such as CryptoAPI) which represent the buffer in little endian format.

 =item B<-sign>

 sign the input data and output the signed result. This requires
 a private key.

 =item B<-verify>

 verify the input data against the signature file and indicate if the
 verification succeeded or failed.

 =item B<-verifyrecover>

 verify the input data and output the recovered data.

 =item B<-encrypt>

 encrypt the input data using a public key.

 =item B<-decrypt>

 decrypt the input data using a private key.

 =item B<-derive>

 derive a shared secret using the peer key.

 =item B<-kdf algorithm>

 Use key derivation function B<algorithm>.  The supported algorithms are
 at present B<TLS1-PRF> and B<HKDF>.
 Note: additional parameters and the KDF output length will normally have to be
 set for this to work.
 See L<EVP_PKEY_CTX_set_hkdf_md(3)> and L<EVP_PKEY_CTX_set_tls1_prf_md(3)>
 for the supported string parameters of each algorithm.

 =item B<-kdflen length>

 Set the output length for KDF.

 =item B<-pkeyopt opt:value>

 Public key options specified as opt:value. See NOTES below for more details.

 =item B<-hexdump>

 hex dump the output data.

 =item B<-asn1parse>

 asn1parse the output data, this is useful when combined with the
 B<-verifyrecover> option when an ASN1 structure is signed.

 =item B<-engine id>

 specifying an engine (by its unique B<id> string) will cause B<pkeyutl>
 to attempt to obtain a functional reference to the specified engine,
 thus initialising it if needed. The engine will then be set as the default
 for all available algorithms.

 =item B<-engine_impl>

 When used with the B<-engine> option, it specifies to also use
 engine B<id> for crypto operations.

 =back

 =head1 NOTES

 The operations and options supported vary according to the key algorithm
 and its implementation. The OpenSSL operations and options are indicated below.

 Unless otherwise mentioned all algorithms support the B<digest:alg> option
 which specifies the digest in use for sign, verify and verifyrecover operations.
 The value B<alg> should represent a digest name as used in the
 EVP_get_digestbyname() function for example B<sha1>.
 This value is used only for sanity-checking the lengths of data passed in to
 the B<pkeyutl> and for creating the structures that make up the signature
 (e.g. B<DigestInfo> in RSASSA PKCS#1 v1.5 signatures).
 In case of RSA, ECDSA and DSA signatures, this utility
 will not perform hashing on input data but rather use the data directly as
 input of signature algorithm. Depending on key type, signature type and mode
 of padding, the maximum acceptable lengths of input data differ. In general,
 with RSA the signed data can't be longer than the key modulus, in case of ECDSA
 and DSA the data shouldn't be longer than field size, otherwise it will be
 silently truncated to field size.

 In other words, if the value of digest is B<sha1> the input should be 20 bytes
 long binary encoding of SHA-1 hash function output.

 =head1 RSA ALGORITHM

 The RSA algorithm generally supports the encrypt, decrypt, sign,
 verify and verifyrecover operations. However, some padding modes
 support only a subset of these operations. The following additional
 B<pkeyopt> values are supported:

 =over 4

 =item B<rsa_padding_mode:mode>

 This sets the RSA padding mode. Acceptable values for B<mode> are B<pkcs1> for
 PKCS#1 padding, B<sslv23> for SSLv23 padding, B<none> for no padding, B<oaep>
 for B<OAEP> mode, B<x931> for X9.31 mode and B<pss> for PSS.

 In PKCS#1 padding if the message digest is not set then the supplied data is
 signed or verified directly instead of using a B<DigestInfo> structure. If a
 digest is set then the a B<DigestInfo> structure is used and its the length
 must correspond to the digest type.

 For B<oaep> mode only encryption and decryption is supported.

 For B<x931> if the digest type is set it is used to format the block data
 otherwise the first byte is used to specify the X9.31 digest ID. Sign,
 verify and verifyrecover are can be performed in this mode.

 For B<pss> mode only sign and verify are supported and the digest type must be
 specified.

 =item B<rsa_pss_saltlen:len>

 For B<pss> mode only this option specifies the salt length. Three special
 values are supported: "digest" sets the salt length to the digest length,
 "max" sets the salt length to the maximum permissible value. When verifying
 "auto" causes the salt length to be automatically determined based on the
 B<PSS> block structure.

 =item B<rsa_mgf1_md:digest>

 For PSS and OAEP padding sets the MGF1 digest. If the MGF1 digest is not
 explicitly set in PSS mode then the signing digest is used.

 =back

 =head1 RSA-PSS ALGORITHM

 The RSA-PSS algorithm is a restricted version of the RSA algorithm which only
 supports the sign and verify operations with PSS padding. The following
 additional B<pkeyopt> values are supported:

 =over 4

 =item B<rsa_padding_mode:mode>, B<rsa_pss_saltlen:len>, B<rsa_mgf1_md:digest>

 These have the same meaning as the B<RSA> algorithm with some additional
 restrictions. The padding mode can only be set to B<pss> which is the
 default value.

 If the key has parameter restrictions than the digest, MGF1
 digest and salt length are set to the values specified in the parameters.
 The digest and MG cannot be changed and the salt length cannot be set to a
 value less than the minimum restriction.

 =back

 =head1 DSA ALGORITHM

 The DSA algorithm supports signing and verification operations only. Currently
 there are no additional options other than B<digest>. Only the SHA1
 digest can be used and this digest is assumed by default.

 =head1 DH ALGORITHM

 The DH algorithm only supports the derivation operation and no additional
 options.

 =head1 EC ALGORITHM

 The EC algorithm supports sign, verify and derive operations. The sign and
 verify operations use ECDSA and derive uses ECDH. Currently there are no
 additional options other than B<digest>. Only the SHA1 digest can be used and
 this digest is assumed by default.

 =head1 X25519 ALGORITHM

 The X25519 algorithm supports key derivation only. Currently there are no
 additional options.

 =head1 EXAMPLES

 Sign some data using a private key:

  openssl pkeyutl -sign -in file -inkey key.pem -out sig

 Recover the signed data (e.g. if an RSA key is used):

  openssl pkeyutl -verifyrecover -in sig -inkey key.pem

 Verify the signature (e.g. a DSA key):

  openssl pkeyutl -verify -in file -sigfile sig -inkey key.pem

 Sign data using a message digest value (this is currently only valid for RSA):

  openssl pkeyutl -sign -in file -inkey key.pem -out sig -pkeyopt digest:sha256

 Derive a shared secret value:

  openssl pkeyutl -derive -inkey key.pem -peerkey pubkey.pem -out secret

 Hexdump 48 bytes of TLS1 PRF using digest B<SHA256> and shared secret and
 seed consisting of the single byte 0xFF:

  openssl pkeyutl -kdf TLS1-PRF -kdflen 48 -pkeyopt md:SHA256 \
     -pkeyopt hexsecret:ff -pkeyopt hexseed:ff -hexdump

 =head1 SEE ALSO

 L<genpkey(1)>, L<pkey(1)>, L<rsautl(1)>
 L<dgst(1)>, L<rsa(1)>, L<genrsa(1)>,
 L<EVP_PKEY_CTX_set_hkdf_md(3)>, L<EVP_PKEY_CTX_set_tls1_prf_md(3)>

 =head1 COPYRIGHT

 Copyright 2006-2016 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
	=pod

	=head1 NAME

	pkeyutl - public key algorithm utility

	=head1 SYNOPSIS

	B<openssl> B<pkeyutl>
	[B<-help>]
	[B<-in file>]
	[B<-out file>]
	[B<-sigfile file>]
	[B<-inkey file>]
	[B<-keyform PEM\|DER\|ENGINE>]
	[B<-passin arg>]
	[B<-peerkey file>]
	[B<-peerform PEM\|DER\|ENGINE>]
	[B<-pubin>]
	[B<-certin>]
	[B<-rev>]
	[B<-sign>]
	[B<-verify>]
	[B<-verifyrecover>]
	[B<-encrypt>]
	[B<-decrypt>]
	[B<-derive>]
	[B<-kdf algorithm>]
	[B<-kdflen length>]
	[B<-pkeyopt opt:value>]
	[B<-hexdump>]
	[B<-asn1parse>]
	[B<-engine id>]
	[B<-engine_impl>]

	=head1 DESCRIPTION

	The B<pkeyutl> command can be used to perform public key operations using
	any supported algorithm.

	=head1 OPTIONS

	=over 4

	=item B<-help>

	Print out a usage message.

	=item B<-in filename>

	This specifies the input filename to read data from or standard input
	if this option is not specified.

	=item B<-out filename>

	specifies the output filename to write to or standard output by
	default.

	=item B<-sigfile file>

	Signature file, required for B<verify> operations only

	=item B<-inkey file>

	the input key file, by default it should be a private key.

	=item B<-keyform PEM\|DER\|ENGINE>

	the key format PEM, DER or ENGINE. Default is PEM.

	=item B<-passin arg>

	the input 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<-peerkey file>

	the peer key file, used by key derivation (agreement) operations.

	=item B<-peerform PEM\|DER\|ENGINE>

	the peer key format PEM, DER or ENGINE. Default is PEM.

	=item B<-pubin>

	the input file is a public key.

	=item B<-certin>

	the input is a certificate containing a public key.

	=item B<-rev>

	reverse the order of the input buffer. This is useful for some libraries
	(such as CryptoAPI) which represent the buffer in little endian format.

	=item B<-sign>

	sign the input data and output the signed result. This requires
	a private key.

	=item B<-verify>

	verify the input data against the signature file and indicate if the
	verification succeeded or failed.

	=item B<-verifyrecover>

	verify the input data and output the recovered data.

	=item B<-encrypt>

	encrypt the input data using a public key.

	=item B<-decrypt>

	decrypt the input data using a private key.

	=item B<-derive>

	derive a shared secret using the peer key.

	=item B<-kdf algorithm>

	Use key derivation function B<algorithm>. The supported algorithms are
	at present B<TLS1-PRF> and B<HKDF>.
	Note: additional parameters and the KDF output length will normally have to be
	set for this to work.
	See L<EVP_PKEY_CTX_set_hkdf_md(3)> and L<EVP_PKEY_CTX_set_tls1_prf_md(3)>
	for the supported string parameters of each algorithm.

	=item B<-kdflen length>

	Set the output length for KDF.

	=item B<-pkeyopt opt:value>

	Public key options specified as opt:value. See NOTES below for more details.

	=item B<-hexdump>

	hex dump the output data.

	=item B<-asn1parse>

	asn1parse the output data, this is useful when combined with the
	B<-verifyrecover> option when an ASN1 structure is signed.

	=item B<-engine id>

	specifying an engine (by its unique B<id> string) will cause B<pkeyutl>
	to attempt to obtain a functional reference to the specified engine,
	thus initialising it if needed. The engine will then be set as the default
	for all available algorithms.

	=item B<-engine_impl>

	When used with the B<-engine> option, it specifies to also use
	engine B<id> for crypto operations.

	=back

	=head1 NOTES

	The operations and options supported vary according to the key algorithm
	and its implementation. The OpenSSL operations and options are indicated below.

	Unless otherwise mentioned all algorithms support the B<digest:alg> option
	which specifies the digest in use for sign, verify and verifyrecover operations.
	The value B<alg> should represent a digest name as used in the
	EVP_get_digestbyname() function for example B<sha1>.
	This value is used only for sanity-checking the lengths of data passed in to
	the B<pkeyutl> and for creating the structures that make up the signature
	(e.g. B<DigestInfo> in RSASSA PKCS#1 v1.5 signatures).
	In case of RSA, ECDSA and DSA signatures, this utility
	will not perform hashing on input data but rather use the data directly as
	input of signature algorithm. Depending on key type, signature type and mode
	of padding, the maximum acceptable lengths of input data differ. In general,
	with RSA the signed data can't be longer than the key modulus, in case of ECDSA
	and DSA the data shouldn't be longer than field size, otherwise it will be
	silently truncated to field size.

	In other words, if the value of digest is B<sha1> the input should be 20 bytes
	long binary encoding of SHA-1 hash function output.

	=head1 RSA ALGORITHM

	The RSA algorithm generally supports the encrypt, decrypt, sign,
	verify and verifyrecover operations. However, some padding modes
	support only a subset of these operations. The following additional
	B<pkeyopt> values are supported:

	=over 4

	=item B<rsa_padding_mode:mode>

	This sets the RSA padding mode. Acceptable values for B<mode> are B<pkcs1> for
	PKCS#1 padding, B<sslv23> for SSLv23 padding, B<none> for no padding, B<oaep>
	for B<OAEP> mode, B<x931> for X9.31 mode and B<pss> for PSS.

	In PKCS#1 padding if the message digest is not set then the supplied data is
	signed or verified directly instead of using a B<DigestInfo> structure. If a
	digest is set then the a B<DigestInfo> structure is used and its the length
	must correspond to the digest type.

	For B<oaep> mode only encryption and decryption is supported.

	For B<x931> if the digest type is set it is used to format the block data
	otherwise the first byte is used to specify the X9.31 digest ID. Sign,
	verify and verifyrecover are can be performed in this mode.

	For B<pss> mode only sign and verify are supported and the digest type must be
	specified.

	=item B<rsa_pss_saltlen:len>

	For B<pss> mode only this option specifies the salt length. Three special
	values are supported: "digest" sets the salt length to the digest length,
	"max" sets the salt length to the maximum permissible value. When verifying
	"auto" causes the salt length to be automatically determined based on the
	B<PSS> block structure.

	=item B<rsa_mgf1_md:digest>

	For PSS and OAEP padding sets the MGF1 digest. If the MGF1 digest is not
	explicitly set in PSS mode then the signing digest is used.

	=back

	=head1 RSA-PSS ALGORITHM

	The RSA-PSS algorithm is a restricted version of the RSA algorithm which only
	supports the sign and verify operations with PSS padding. The following
	additional B<pkeyopt> values are supported:

	=over 4

	=item B<rsa_padding_mode:mode>, B<rsa_pss_saltlen:len>, B<rsa_mgf1_md:digest>

	These have the same meaning as the B<RSA> algorithm with some additional
	restrictions. The padding mode can only be set to B<pss> which is the
	default value.

	If the key has parameter restrictions than the digest, MGF1
	digest and salt length are set to the values specified in the parameters.
	The digest and MG cannot be changed and the salt length cannot be set to a
	value less than the minimum restriction.

	=back

	=head1 DSA ALGORITHM

	The DSA algorithm supports signing and verification operations only. Currently
	there are no additional options other than B<digest>. Only the SHA1
	digest can be used and this digest is assumed by default.

	=head1 DH ALGORITHM

	The DH algorithm only supports the derivation operation and no additional
	options.

	=head1 EC ALGORITHM

	The EC algorithm supports sign, verify and derive operations. The sign and
	verify operations use ECDSA and derive uses ECDH. Currently there are no
	additional options other than B<digest>. Only the SHA1 digest can be used and
	this digest is assumed by default.

	=head1 X25519 ALGORITHM

	The X25519 algorithm supports key derivation only. Currently there are no
	additional options.

	=head1 EXAMPLES

	Sign some data using a private key:

	openssl pkeyutl -sign -in file -inkey key.pem -out sig

	Recover the signed data (e.g. if an RSA key is used):

	openssl pkeyutl -verifyrecover -in sig -inkey key.pem

	Verify the signature (e.g. a DSA key):

	openssl pkeyutl -verify -in file -sigfile sig -inkey key.pem

	Sign data using a message digest value (this is currently only valid for RSA):

	openssl pkeyutl -sign -in file -inkey key.pem -out sig -pkeyopt digest:sha256

	Derive a shared secret value:

	openssl pkeyutl -derive -inkey key.pem -peerkey pubkey.pem -out secret

	Hexdump 48 bytes of TLS1 PRF using digest B<SHA256> and shared secret and
	seed consisting of the single byte 0xFF:

	openssl pkeyutl -kdf TLS1-PRF -kdflen 48 -pkeyopt md:SHA256 \
	-pkeyopt hexsecret:ff -pkeyopt hexseed:ff -hexdump

	=head1 SEE ALSO

	L<genpkey(1)>, L<pkey(1)>, L<rsautl(1)>
	L<dgst(1)>, L<rsa(1)>, L<genrsa(1)>,
	L<EVP_PKEY_CTX_set_hkdf_md(3)>, L<EVP_PKEY_CTX_set_tls1_prf_md(3)>

	=head1 COPYRIGHT

	Copyright 2006-2016 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