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OPENSSL-PKEYUTL(1ossl)              OpenSSL             OPENSSL-PKEYUTL(1ossl)


       openssl-pkeyutl - public key algorithm command


       openssl pkeyutl [-help] [-in file] [-rawin] [-digest algorithm] [-out
       file] [-sigfile file] [-inkey filename|uri] [-keyform
       DER|PEM|P12|ENGINE] [-passin arg] [-peerkey file] [-peerform
       DER|PEM|P12|ENGINE] [-pubin] [-certin] [-rev] [-sign] [-verify]
       [-verifyrecover] [-encrypt] [-decrypt] [-derive] [-kdf algorithm]
       [-kdflen length] [-pkeyopt opt:value] [-pkeyopt_passin opt[:passarg]]
       [-hexdump] [-asn1parse] [-engine id] [-engine_impl] [-rand files]
       [-writerand file] [-provider name] [-provider-path path] [-propquery
       propq] [-config configfile]


       This command can be used to perform low-level public key operations
       using any supported algorithm.


           Print out a usage message.

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

           This indicates that the input data is raw data, which is not hashed
           by any message digest algorithm. The user can specify a digest
           algorithm by using the -digest option. This option can only be used
           with -sign and -verify and must be used with the Ed25519 and Ed448

       -digest algorithm
           This specifies the digest algorithm which is used to hash the input
           data before signing or verifying it with the input key. This option
           could be omitted if the signature algorithm does not require one
           (for instance, EdDSA). If this option is omitted but the signature
           algorithm requires one, a default value will be used. For signature
           algorithms like RSA, DSA and ECDSA, SHA-256 will be the default
           digest algorithm. For SM2, it will be SM3. If this option is
           present, then the -rawin option must be also specified.

       -out filename
           Specifies the output filename to write to or standard output by

       -sigfile file
           Signature file, required for -verify operations only

       -inkey filename|uri
           The input key, by default it should be a private key.

       -keyform DER|PEM|P12|ENGINE
           The key format; unspecified by default.  See
           openssl-format-options(1) for details.

       -passin arg
           The input key password source. For more information about the
           format of arg see openssl-passphrase-options(1).

       -peerkey file
           The peer key file, used by key derivation (agreement) operations.

       -peerform DER|PEM|P12|ENGINE
           The peer key format; unspecified by default.  See
           openssl-format-options(1) for details.

           By default a private key is read from the key input.  With this
           option a public key is read instead.  If the input contains no
           public key but a private key, its public part is used.

           The input is a certificate containing a public key.

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

           Sign the input data (which must be a hash) and output the signed
           result. This requires a private key.

           Verify the input data (which must be a hash) against the signature
           file and indicate if the verification succeeded or failed.

           Verify the input data (which must be a hash) and output the
           recovered data.

           Encrypt the input data using a public key.

           Decrypt the input data using a private key.

           Derive a shared secret using the peer key.

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

       -kdflen length
           Set the output length for KDF.

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

       -pkeyopt_passin opt[:passarg]
           Allows reading a public key option opt from stdin or a password
           source.  If only opt is specified, the user will be prompted to
           enter a password on stdin.  Alternatively, passarg can be specified
           which can be any value supported by openssl-passphrase-options(1).

           hex dump the output data.

           Parse the ASN.1 output data, this is useful when combined with the
           -verifyrecover option when an ASN1 structure is signed.

       -engine id
           See "Engine Options" in openssl(1).  This option is deprecated.

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

       -rand files, -writerand file
           See "Random State Options" in openssl(1) for details.

       -provider name
       -provider-path path
       -propquery propq
           See "Provider Options" in openssl(1), provider(7), and property(7).

       -config configfile
           See "Configuration Option" in openssl(1).


       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 digest:alg option
       which specifies the digest in use for sign, verify and verifyrecover
       operations.  The value alg should represent a digest name as used in
       the EVP_get_digestbyname() function for example sha1. This value is not
       used to hash the input data. It is used (by some algorithms) for
       sanity-checking the lengths of data passed in and for creating the
       structures that make up the signature (e.g. DigestInfo in RSASSA PKCS#1
       v1.5 signatures).

       This command does not hash the input data (except where -rawin is used)
       but rather it will use the data directly as input to the signature
       algorithm.  Depending on the key type, signature type, and mode of
       padding, the maximum acceptable lengths of input data differ. The
       signed data can't be longer than the key modulus with RSA. In case of
       ECDSA and DSA the data shouldn't be longer than the field size,
       otherwise it will be silently truncated to the field size.  In any
       event the input size must not be larger than the largest supported
       digest size.

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


       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 pkeyopt values
       are supported:

           This sets the RSA padding mode. Acceptable values for mode are
           pkcs1 for PKCS#1 padding, none for no padding, oaep for OAEP mode,
           x931 for X9.31 mode and 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
           DigestInfo structure. If a digest is set then the a DigestInfo
           structure is used and its the length must correspond to the digest

           Note, for pkcs1 padding, as a protection against Bleichenbacher
           attack, the decryption will not fail in case of padding check
           failures. Use none and manual inspection of the decrypted message
           to verify if the decrypted value has correct PKCS#1 v1.5 padding.

           For oaep mode only encryption and decryption is supported.

           For 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

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

           For 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 PSS block structure.

           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.

           Sets the digest used for the OAEP hash function. If not explicitly
           set then SHA1 is used.

           Disables (when set to 0) or enables (when set to 1) the use of
           implicit rejection with PKCS#1 v1.5 decryption. When enabled (the
           default), as a protection against Bleichenbacher attack, the
           library will generate a deterministic random plaintext that it will
           return to the caller in case of padding check failure.  When
           disabled, it's the callers' responsibility to handle the returned
           errors in a side-channel free manner.


       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 -pkeyopt values are supported:

       rsa_padding_mode:mode, rsa_pss_saltlen:len, rsa_mgf1_md:digest
           These have the same meaning as the RSA algorithm with some
           additional restrictions. The padding mode can only be set to pss
           which is the default value.

           If the key has parameter restrictions then 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.


       The DSA algorithm supports signing and verification operations only.
       Currently there are no additional -pkeyopt options other than digest.
       The SHA1 digest is assumed by default.


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


       The EC algorithm supports sign, verify and derive operations. The sign
       and verify operations use ECDSA and derive uses ECDH. SHA1 is assumed
       by default for the -pkeyopt digest option.


       The X25519 and X448 algorithms support key derivation only. Currently
       there are no additional options.


       These algorithms only support signing and verifying. OpenSSL only
       implements the "pure" variants of these algorithms so raw data can be
       passed directly to them without hashing them first. The option -rawin
       must be used with these algorithms with no -digest specified.
       Additionally OpenSSL only supports "oneshot" operation with these
       algorithms. This means that the entire file to be signed/verified must
       be read into memory before processing it. Signing or Verifying very
       large files should be avoided. Additionally the size of the file must
       be known for this to work. If the size of the file cannot be determined
       (for example if the input is stdin) then the sign or verify operation
       will fail.


       The SM2 algorithm supports sign, verify, encrypt and decrypt
       operations. For the sign and verify operations, SM2 requires an
       Distinguishing ID string to be passed in. The following -pkeyopt value
       is supported:

           This sets the ID string used in SM2 sign or verify operations.
           While verifying an SM2 signature, the ID string must be the same
           one used when signing the data.  Otherwise the verification will

           This sets the ID string used in SM2 sign or verify operations.
           While verifying an SM2 signature, the ID string must be the same
           one used when signing the data.  Otherwise the verification will
           fail. The ID string provided with this option should be a valid
           hexadecimal value.


       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 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

       Derive a key using scrypt where the password is read from command line:

        openssl pkeyutl -kdf scrypt -kdflen 16 -pkeyopt_passin pass \
           -pkeyopt hexsalt:aabbcc -pkeyopt N:16384 -pkeyopt r:8 -pkeyopt p:1

       Derive using the same algorithm, but read key from environment variable

        openssl pkeyutl -kdf scrypt -kdflen 16 -pkeyopt_passin pass:env:MYPASS \
           -pkeyopt hexsalt:aabbcc -pkeyopt N:16384 -pkeyopt r:8 -pkeyopt p:1

       Sign some data using an SM2(7) private key and a specific ID:

        openssl pkeyutl -sign -in file -inkey sm2.key -out sig -rawin -digest sm3 \
           -pkeyopt distid:someid

       Verify some data using an SM2(7) certificate and a specific ID:

        openssl pkeyutl -verify -certin -in file -inkey sm2.cert -sigfile sig \
           -rawin -digest sm3 -pkeyopt distid:someid

       Decrypt some data using a private key with OAEP padding using SHA256:

        openssl pkeyutl -decrypt -in file -inkey key.pem -out secret \
           -pkeyopt rsa_padding_mode:oaep -pkeyopt rsa_oaep_md:sha256


       openssl(1), openssl-genpkey(1), openssl-pkey(1), openssl-rsautl(1)
       openssl-dgst(1), openssl-rsa(1), openssl-genrsa(1), openssl-kdf(1)
       EVP_PKEY_CTX_set_hkdf_md(3), EVP_PKEY_CTX_set_tls1_prf_md(3),


       The -engine option was deprecated in OpenSSL 3.0.


       Copyright 2006-2023 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (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

3.2.0                             2023-11-23            OPENSSL-PKEYUTL(1ossl)

openssl 3.2.0 - Generated Wed Nov 29 07:54:05 CST 2023
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