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GENRSA(1)			    OpenSSL			     GENRSA(1)

       genrsa -	generate an RSA	private	key

       openssl genrsa [-out filename] [-passout	arg] [-aes128] [-aes192]
       [-aes256] [-camellia128]	[-camellia192] [-camellia256] [-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
	   standard 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 specified	cipher 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
	   number generator, or	an EGD socket (see RAND_egd(3)).  Multiple
	   files can be	specified separated by a OS-dependent character.  The
	   separator is	; for MS-Windows, , for	OpenVMS, and : for all others.

       -engine id
	   specifying an engine	(by its	unique id string) will cause genrsa 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
       reasons they will be much larger	(typically 1024	bits).


1.0.2h				  2016-05-03			     GENRSA(1)


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