Entropy in the Linux Kernel - Revision history

Leo: /* See Also */

2020-06-15T02:05:06Z

2020-06-15T02:04:48Z

Leo moved page Entropy to Entropy in the Linux Kernel: more appropriate naming

← Older revision		Revision as of 02:04, 15 June 2020
(No difference)

2019-09-02T02:08:04Z

Visualizing Randomness

← Older revision		Revision as of 02:08, 2 September 2019
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	== Visualizing Randomness ==		== Visualizing Randomness ==
	The following PHP script will let you generate bitmap from data piped to the script. You can also use the commented out line to visualize PHP's {{code\|rand}} function.		The following PHP script will let you generate bitmap from data piped to the script. You can also use the commented out line to visualize PHP's {{code\|rand}} function. This script can be found at http://api.leo.leung.xyz/random

	{{highlight\|lang=php\|code=		{{highlight\|lang=php\|code=

2019-09-01T06:21:20Z

Text replacement - "Category:Linux{{Navbox Linux}}" to "{{Navbox Linux}}Category:Linux"

2019-09-01T05:08:48Z

Text replacement - "Category:Linux" to "Category:Linux{{Navbox Linux}}"

2017-02-24T04:26:25Z

Text replacement - "{{Highlight" to "{{highlight"

← Older revision		Revision as of 04:26, 24 February 2017
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	You can see the size of the entropy pool size in linux by running:		You can see the size of the entropy pool size in linux by running:

	{{~~Highlight~~\|lang=terminal\|code=		{{highlight\|lang=terminal\|code=
	# cat /proc/sys/kernel/random/poolsize		# cat /proc/sys/kernel/random/poolsize
	}}		}}
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	The number of 'bits' of entropy can be seen at:		The number of 'bits' of entropy can be seen at:

	{{~~Highlight~~\|lang=terminal\|code=		{{highlight\|lang=terminal\|code=
	# cat /proc/sys/kernel/random/entropy_avail		# cat /proc/sys/kernel/random/entropy_avail
	}}		}}

2015-12-09T22:18:54Z

format highlight

← Older revision		Revision as of 22:18, 9 December 2015
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	You can see the size of the entropy pool size in linux by running:		You can see the size of the entropy pool size in linux by running:

	{{Highlight\|lang=~~bash~~\|code=		{{Highlight\|lang=terminal\|code=
	cat /proc/sys/kernel/random/poolsize		# cat /proc/sys/kernel/random/poolsize
	}}		}}

	The number of 'bits' of entropy can be seen at:		The number of 'bits' of entropy can be seen at:

	{{Highlight\|lang=~~bash~~\|code=		{{Highlight\|lang=terminal\|code=
	cat /proc/sys/kernel/random/entropy_avail		# cat /proc/sys/kernel/random/entropy_avail
	}}		}}

2015-11-23T07:28:47Z

entropy source

← Older revision		Revision as of 07:28, 23 November 2015
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	On Linux, {{code\|/dev/random}} and {{code\|/dev/urandom}} are pseudo devices that provide random numbers. Both devices are supplied by the kernel's PRNG, though {{code\|/dev/random}} will block when the entropy pool is depleted while {{code\|/dev/urandom}} will continue to generate random numbers.		On Linux, {{code\|/dev/random}} and {{code\|/dev/urandom}} are pseudo devices that provide random numbers. Both devices are supplied by the kernel's PRNG, though {{code\|/dev/random}} will block when the entropy pool is depleted while {{code\|/dev/urandom}} will continue to generate random numbers.

			For a cheap entropy source, see [[Entropy Source using RTL-SDR]].

	== Linux Entropy Pool ==		== Linux Entropy Pool ==

2015-11-23T07:26:33Z

visualization

@@ Line 14: / Line 14: @@
 {{Highlight|lang=bash|code=
 cat /proc/sys/kernel/random/entropy_avail
 }}

2015-09-21T07:37:15Z

wording

← Older revision		Revision as of 07:37, 21 September 2015
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	Entropy is required to generate random numbers. ~~{{code\|/dev/random}}~~ and ~~{{code\|/dev/urandom}} on Linux provide a way to access random numbers. Both devices are supplied by~~ the ~~kernel~~'~~s PRNG, though {{code\|/dev/random}} will block when the~~ entropy pool ~~is depleted while {{code\|/dev/urandom}} will continue to generate random numbers~~.		Entropy is required to generate good random numbers. Modern operating systems will use physical hardware as sources for entropy and the 'randomness' goes into an entropy pool for future use.

	== Entropy ~~Pools~~ ==		On Linux, {{code\|/dev/random}} and {{code\|/dev/urandom}} are pseudo devices that provide random numbers. Both devices are supplied by the kernel's PRNG, though {{code\|/dev/random}} will block when the entropy pool is depleted while {{code\|/dev/urandom}} will continue to generate random numbers.

			== Linux Entropy Pool ==
	You can see the size of the entropy pool size in linux by running:		You can see the size of the entropy pool size in linux by running:

← Older revision		Revision as of 02:05, 15 June 2020
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	* http://www.2uo.de/myths-about-urandom/		* http://www.2uo.de/myths-about-urandom/

	~~{{Navbox_Linux}}~~
	{{Navbox Linux}}[[Category:Linux]]		{{Navbox Linux}}[[Category:Linux]]