EC 1 2005-11-24 0.9.9-dev OpenSSL
NAME
ec - EC key processing
LIBRARY
libcrypto, -lcrypto
SYNOPSIS
ooppeennssssll eecc
[--iinnffoorrmm PPEEMM||DDEERR]
[--oouuttffoorrmm PPEEMM||DDEERR]
[--iinn ffiilleennaammee]
[--ppaassssiinn aarrgg]
[--oouutt ffiilleennaammee]
[--ppaassssoouutt aarrgg]
[--ddeess]
[--ddeess33]
[--iiddeeaa]
[--tteexxtt]
[--nnoooouutt]
[--ppaarraamm__oouutt]
[--ppuubbiinn]
[--ppuubboouutt]
[--ccoonnvv__ffoorrmm aarrgg]
[--ppaarraamm__eenncc aarrgg]
[--eennggiinnee iidd]
DESCRIPTION
The eecc command processes EC keys. They can be converted between various
forms and their components printed out. NNoottee OpenSSL uses the
private key format specified in 'SEC 1: Elliptic Curve Cryptography'
(http://www.secg.org/). To convert a OpenSSL EC private key into the
PKCS#8 private key format use the ppkkccss88 command.
COMMAND OPTIONS
-
--iinnffoorrmm DDEERR||PPEEMM
This specifies the input format. The DDEERR option with a private key uses
-
an ASN.1 DER encoded SEC1 private key. When used with a public key it
uses the SubjectPublicKeyInfo structur as specified in RFC 3280.
The PPEEMM form is the default format: it consists of the DDEERR format base64
encoded with additional header and footer lines. In the case of a private key
PKCS#8 format is also accepted.
-
--oouuttffoorrmm DDEERR||PPEEMM
This specifies the output format, the options have the same meaning as the
-
--iinnffoorrmm option.
-
--iinn ffiilleennaammee
This specifies the input filename to read a key from or standard input if this
-
option is not specified. If the key is encrypted a pass phrase will be
prompted for.
-
--ppaassssiinn aarrgg
the input file password source. For more information about the format of aarrgg
-
see the PPAASSSS PPHHRRAASSEE AARRGGUUMMEENNTTSS section in _o_p_e_n_s_s_l(1).
-
--oouutt ffiilleennaammee
This specifies the output filename to write a key to or standard output by
-
is not specified. If any encryption options are set then a pass phrase will be
prompted for. The output filename should nnoott be the same as the input
filename.
-
--ppaassssoouutt aarrgg
the output file password source. For more information about the format of aarrgg
-
see the PPAASSSS PPHHRRAASSEE AARRGGUUMMEENNTTSS section in _o_p_e_n_s_s_l(1).
-
--ddeess||--ddeess33||--iiddeeaa
These options encrypt the private key with the DES, triple DES, IDEA or
-
any other cipher supported by OpenSSL before outputting it. A pass phrase is
prompted for.
If none of these options is specified the key is written in plain text. This
means that using the eecc utility to read in an encrypted key with no
encryption option can be used to remove the pass phrase from a key, or by
setting the encryption options it can be use to add or change the pass phrase.
These options can only be used with PEM format output files.
-
--tteexxtt
prints out the public, private key components and parameters.
-
-
--nnoooouutt
this option prevents output of the encoded version of the key.
-
-
--mmoodduulluuss
this option prints out the value of the public key component of the key.
-
-
--ppuubbiinn
by default a private key is read from the input file: with this option a
-
public key is read instead.
-
--ppuubboouutt
by default a private key is output. With this option a public
-
key will be output instead. This option is automatically set if the input is
a public key.
-
--ccoonnvv__ffoorrmm
This specifies how the points on the elliptic curve are converted
-
into octet strings. Possible values are: ccoommpprreesssseedd (the default
value), uunnccoommpprreesssseedd and hhyybbrriidd. For more information regarding
the point conversion forms please read the X9.62 standard.
NNoottee Due to patent issues the ccoommpprreesssseedd option is disabled
by default for binary curves and can be enabled by defining
the preprocessor macro OOPPEENNSSSSLL__EECC__BBIINN__PPTT__CCOOMMPP at compile time.
-
--ppaarraamm__eenncc aarrgg
This specifies how the elliptic curve parameters are encoded.
-
Possible value are: nnaammeedd__ccuurrvvee, i.e. the ec parameters are
specified by a OID, or eexxpplliicciitt where the ec parameters are
explicitly given (see RFC 3279 for the definition of the
EC parameters structures). The default value is nnaammeedd__ccuurrvvee.
NNoottee the iimmpplliicciittllyyCCAA alternative ,as specified in RFC 3279,
is currently not implemented in OpenSSL.
-
--eennggiinnee iidd
specifying an engine (by it's unique iidd string) will cause rreeqq
-
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.
NOTES
The PEM private key format uses the header and footer lines:
-----BEGIN EC PRIVATE KEY-----
-----END EC PRIVATE KEY-----
The PEM public key format uses the header and footer lines:
-----BEGIN PUBLIC KEY-----
-----END PUBLIC KEY-----
EXAMPLES
To encrypt a private key using triple DES:
openssl ec -in key.pem -des3 -out keyout.pem
To convert a private key from PEM to DER format:
openssl ec -in key.pem -outform DER -out keyout.der
To print out the components of a private key to standard output:
openssl ec -in key.pem -text -noout
To just output the public part of a private key:
openssl ec -in key.pem -pubout -out pubkey.pem
To change the parameters encoding to eexxpplliicciitt:
openssl ec -in key.pem -param_enc explicit -out keyout.pem
To change the point conversion form to ccoommpprreesssseedd:
openssl ec -in key.pem -conv_form compressed -out keyout.pem
SEE ALSO
_e_c_p_a_r_a_m(1), _o_p_e_n_s_s_l___d_s_a(1), _o_p_e_n_s_s_l___r_s_a(1)
HISTORY
The ec command was first introduced in OpenSSL 0.9.8.
AUTHOR
Nils Larsch for the OpenSSL project (http://www.openssl.org).