1IPSEC_RANBITS(8)                [FIXME: manual]               IPSEC_RANBITS(8)
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NAME

6       ipsec_ranbits - generate random bits in ASCII form
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SYNOPSIS

9       ipsec ranbits [--quick] [--continuous] [--bytes] nbits
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DESCRIPTION

12       Ranbits obtains nbits (rounded up to the nearest byte) high-quality
13       random bits from random(4), and emits them on standard output as an
14       ASCII string. The default output format is datatot(3) h format:
15       lowercase hexadecimal with a 0x prefix and an underscore every 32 bits.
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17       The --quick option produces quick-and-dirty random bits: instead of
18       using the high-quality random bits from /dev/random, which may take
19       some time to supply the necessary bits if nbits is large, ranbits uses
20       /dev/urandom, which yields prompt results but lower-quality randomness.
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22       The --continuous option uses datatot(3) x output format, like h but
23       without the underscores.
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25       The --bytes option causes nbits to be interpreted as a byte count
26       rather than a bit count.
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FILES

29       /dev/random, /dev/urandom
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SEE ALSO

32       ipsec_datatot(3), random(4)
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HISTORY

35       Written for the Linux FreeS/WAN project <http://www.freeswan.org> by
36       Henry Spencer.
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BUGS

39       There is an internal limit on nbits, currently 20000.
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41       Without --quick, ranbits´s run time is difficult to predict. A request
42       for a large number of bits, at a time when the system´s entropy pool is
43       low on randomness, may take quite a while to satisfy.
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45       Though not a bug of ranbits, the direct use of /dev/hw_random, the
46       Linux hardware random number generator is not supported because it can
47       produce very non-random data. To properly use /dev/hw_random, the rngd
48       daemon should be used to read from /dev/hw_random and write to
49       /dev/random, while performing a FIPS test on the hardware random read.
50       No changes to Openswan are required for this support - just a running
51       rngd.
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55[FIXME: source]                   10/06/2010                  IPSEC_RANBITS(8)