dsa

 

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 DSA(1)                       OpenSSL                       DSA(1)
 
 
 
 NAME
        dsa - DSA key processing
 
 SYNOPSIS
        openssl dsa [-inform PEM|DER] [-outform PEM|DER] [-in
        filename] [-passin arg] [-out filename] [-passout arg]
        [-des] [-des3] [-idea] [-text] [-noout] [-modulus]
        [-pubin] [-pubout]
 
 DESCRIPTION
        The dsa command processes DSA keys. They can be converted
        between various forms and their components printed out.
        Note This command uses the traditional SSLeay compatible
        format for private key encryption: newer applications
        should use the more secure PKCS#8 format using the pkcs8
 
 COMMAND OPTIONS
        -inform DER|PEM
            This specifies the input format. The DER option with a
            private key uses an ASN1 DER encoded form of an ASN.1
            SEQUENCE consisting of the values of version
            (currently zero), p, q, g, the public and private key
            components respectively as ASN.1 INTEGERs. When used
            with a public key it uses a SubjectPublicKeyInfo
            structure: it is an error if the key is not DSA.
 
            The PEM form is the default format: it consists of the
            DER format base64 encoded with additional header and
            footer lines. In the case of a private key PKCS#8
            format is also accepted.
 
        -outform DER|PEM
            This specifies the output format, the options have the
            same meaning as the -inform option.
 
        -in filename
            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.
 
        -passin arg
            the input file password source. For more information
            about the format of arg see the PASS PHRASE ARGUMENTS
            section in openssl(1).
 
        -out filename
            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 not be the
            same as the input filename.
 
        -passout arg
            the output file password source. For more information
            about the format of arg see the PASS PHRASE ARGUMENTS
            section in openssl(1).
 
        -des|-des3|-idea
            These options encrypt the private key with the DES,
            triple DES, or the IDEA ciphers respectively 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 dsa 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.
 
        -text
            prints out the public, private key components and
            parameters.
 
        -noout
            this option prevents output of the encoded version of
            the key.
 
        -modulus
            this option prints out the value of the public key
            component of the key.
 
        -pubin
            by default a private key is read from the input file:
            with this option a public key is read instead.
 
        -pubout
            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.
 
 NOTES
        The PEM private key format uses the header and footer
        lines:
 
         -----BEGIN DSA PRIVATE KEY-----
         -----END DSA PRIVATE KEY-----
 
        The PEM public key format uses the header and footer
        lines:
 
         -----BEGIN PUBLIC KEY-----
         -----END PUBLIC KEY-----
 
 
 EXAMPLES
        To remove the pass phrase on a DSA private key:
 
         openssl dsa -in key.pem -out keyout.pem
 
        To encrypt a private key using triple DES:
 
         openssl dsa -in key.pem -des3 -out keyout.pem
 
        To convert a private key from PEM to DER format:
 
         openssl dsa -in key.pem -outform DER -out keyout.der
 
        To print out the components of a private key to standard
        output:
 
         openssl dsa -in key.pem -text -noout
 
        To just output the public part of a private key:
 
         openssl dsa -in key.pem -pubout -out pubkey.pem
 
 
 SEE ALSO
        dsaparam(1), gendsa(1), rsa(1), genrsa(1)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 16/Feb/2000                   0.9.6b                       DSA(1)

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