NAMEpkeyutl - public key algorithm utility
SYNOPSISopenssl pkeyutl [ -in file] [ -out file] [ -sigfile file] [ -inkey file] [ -keyform PEM|DER] [ -passin arg] [ -peerkey file] [ -peerform PEM|DER] [ -pubin] [ -certin] [ -rev] [ -sign] [ -verify] [ -verifyrecover] [ -encrypt] [ -decrypt] [ -derive] [ -pkeyopt opt:value] [ -hexdump] [ -asn1parse] [ -engine id]
DESCRIPTIONThe pkeyutl command can be used to perform public key operations using any supported algorithm.
- -in filename
- This specifies the input filename to read data from or standard input if this option is not specified.
- -out filename
- specifies the output filename to write to or standard output by default.
- -inkey file
- the input key file, by default it should be a private key.
- -keyform PEM|DER
- the key format PEM, DER or ENGINE.
- -passin arg
- the input key password source. For more information about the format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).
- -peerkey file
- the peer key file, used by key derivation (agreement) operations.
- -peerform PEM|DER
- the peer key format PEM, DER or ENGINE.
- -engine id
- specifying an engine (by its unique id string) will cause 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.
- the input file is a public key.
- 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 and output the signed result. This requires a private key.
- verify the input data against the signature file and indicate if the verification succeeded or failed.
- verify the input data 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.
- hex dump the output data.
- asn1parse the output data, this is useful when combined with the -verifyrecover option when an ASN1 structure is signed.
NOTESThe 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.
RSA ALGORITHMThe RSA algorithm supports encrypt, decrypt, sign, verify and verifyrecover operations in general. Some padding modes only support some of these operations however.
- - rsa_padding_mode:mode
This sets the RSA padding mode. Acceptable values for
pkcs1 for PKCS#1 padding,
sslv23 for SSLv23 padding,
none for no padding,
x931 for X9.31 mode and
pss for PSS.
- For pss mode only this option specifies the salt length. Two special values are supported: -1 sets the salt length to the digest length. When signing -2 sets the salt length to the maximum permissible value. When verifying -2 causes the salt length to be automatically determined based on the PSS block structure.
DSA ALGORITHMThe DSA algorithm supports signing and verification operations only. Currently there are no additional options other than digest. Only the SHA1 digest can be used and this digest is assumed by default.
DH ALGORITHMThe DH algorithm only supports the derivation operation and no additional options.
EC ALGORITHMThe 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 digest. Only the SHA1 digest can be used and this digest is assumed by default.
EXAMPLESSign 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
SEE ALSOgenpkey(1), pkey(1), rsautl(1) dgst(1), rsa(1), genrsa(1)