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GENRSA(1)			    OpenSSL			     GENRSA(1)

       genrsa -	generate an RSA	private	key

       openssl genrsa [-out filename] [-passout	arg] [-des] [-des3] [-idea]
       [-f4] [-3] [-rand file(s)] [-engine id] [numbits]

       The genrsa command generates an RSA private key.

       -out filename
	   the output filename.	If this	argument is not	specified then stan-
	   dard	output is used.

       -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. If none of
	   these options is specified no encryption is used. If	encryption is
	   used	a pass phrase is prompted for if it is not supplied via	the
	   -passout argument.

	   the public exponent to use, either 65537 or 3. The default is

       -rand file(s)
	   a file or files containing random data used to seed the random num-
	   ber generator, or an	EGD socket (see	RAND_egd(3)).  Multiple	files
	   can be specified separated by a OS-dependent	character.  The	sepa-
	   rator is ; for MS-Windows, ,	for OpenVMS, and : for all others.

       -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 size of the private key to generate in bits. This must be the
	   last	option specified. The default is 512.

       RSA private key generation essentially involves the generation of two
       prime numbers. When generating a	private	key various symbols will be
       output to indicate the progress of the generation. A . represents each
       number which has	passed an initial sieve	test, +	means a	number has
       passed a	single round of	the Miller-Rabin primality test. A newline
       means that the number has passed	all the	prime tests (the actual	number
       depends on the key size).

       Because key generation is a random process the time taken to generate a
       key may vary somewhat.

       A quirk of the prime generation algorithm is that it cannot generate
       small primes. Therefore the number of bits should not be	less that 64.
       For typical private keys	this will not matter because for security rea-
       sons they will be much larger (typically	1024 bits).


0.9.7d				  2005-02-25			     GENRSA(1)


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