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DSA(1)				    OpenSSL				DSA(1)

       dsa - DSA key processing

       openssl dsa [-inform PEM|DER] [-outform PEM|DER]	[-in filename]
       [-passin	arg] [-out filename] [-passout arg] [-des] [-des3] [-idea]
       [-text] [-noout]	[-modulus] [-pubin] [-pubout] [-engine id]

       The dsa command processes DSA keys. They	can be converted between vari-
       ous 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

       -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 for-
	   mat 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).

	   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 op-
	   tions it can	be use to add or change	the pass phrase.  These	op-
	   tions can only be used with PEM format output files.

	   prints out the public, private key components and parameters.

	   this	option prevents	output of the encoded version of the key.

	   this	option prints out the value of the public key component	of the

	   by default a	private	key is read from the input file: with this op-
	   tion	a public key is	read instead.

	   by default a	private	key is output. With this option	a public key
	   will	be output instead. This	option is automatically	set if the in-
	   put is a public key.

       -engine id
	   specifying an engine	(by it's unique	id string) will	cause req 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 PEM private key format uses the header and footer lines:


       The PEM public key format uses the header and footer lines:

	-----END PUBLIC	KEY-----

       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

       dsaparam(1), gendsa(1), rsa(1), genrsa(1)

0.9.7d				  2005-02-25				DSA(1)


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