Random number generator - Revision history

Ion frigate: Tried to give a good overview of the process

2023-07-13T22:21:07Z

Tried to give a good overview of the process

Aximili: add category:development

2021-05-25T18:53:07Z

add category:development

Phol ende wodan: fix minor grammar issue

2020-10-24T21:47:38Z

fix minor grammar issue

Bhaak: /* Misuse */ TAS by pellsson

2019-01-07T10:57:27Z

‎Misuse: TAS by pellsson

Bhaak: /* Misuse */ Set seed ascension in UnNetHack by nht

2019-01-07T10:52:43Z

‎Misuse: Set seed ascension in UnNetHack by nht

Bhaak: /* Misuse */ countermeasures on NAO-3.4.3 to RNG abuse

2019-01-07T10:08:22Z

‎Misuse: countermeasures on NAO-3.4.3 to RNG abuse

Bhaak: /* Misuse */ link to Adeon's game with the most wishes

2019-01-07T09:53:22Z

‎Misuse: link to Adeon's game with the most wishes

ChasonBot at 21:38, 20 December 2015

2015-12-20T21:38:22Z

Ais523: /* Misuse */ make it clear that Sartak isn't doing the TAS; as written it's a bit ambiguous

2015-06-06T19:22:54Z

‎Misuse: make it clear that Sartak isn't doing the TAS; as written it's a bit ambiguous

Bulwersator: /* Misuse */ and description of [http://gitorious.org/nethack-tas-tools/mainline/blobs/master/turnbyturn.txt#line1657 game relying on extreme RNG manipulation]

2013-05-10T12:39:38Z

‎Misuse: and description of [http://gitorious.org/nethack-tas-tools/mainline/blobs/master/turnbyturn.txt#line1657 game relying on extreme RNG manipulation]

@@ Line 11: / Line 11: @@
 ==Misuse==
 ===3.4.3===
 It was found by Adeon that a sufficiently determined player can find the seed of RNG after starting the game and then use it to his or her advantage - [https://s3.amazonaws.com/altorg/dumplog/Adeon/1236028477.nh343.txt for example to gain unlimited number of wishes from a fountain]. For demonstration see his ttyrecs on NAO from 2009-02-28 (starting with http://alt.org/nethack/trd/?file=http://alt.org/nethack/userdata/A/Adeon/ttyrec/2009-02-28.10:31:15.ttyrec.bz2#). See also Sartak's blog entry ''[http://web.archive.org/web/20090306103017/http://taeb-nethack.blogspot.com/2009/03/predicting-and-controlling-nethacks.html Predicting and controlling NetHack's randomness]'' and ais523's description of a [http://gitorious.org/nethack-tas-tools/mainline/blobs/master/turnbyturn.txt#line1657 game relying on extreme RNG manipulation].
@@ Line 16: / Line 29: @@
 Instead of taking the current time in seconds as seed, NAO has after this exploit been [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/hacklib.c#L480 changed to read the seed from the operating system's own pseudorandom number generator '/dev/urandom']. This way the seed has become unpredictable.
-To also complicate the deducing of the random number generator's internal state, [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/rnd.c#L21 periodic reseeding has been implemented].
+To also complicate the deducing of the random number generator's internal state, [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/rnd.c#L21 periodic reseeding has been implemented].  This makes it so that a player is unlikely to be able to "collect" a sufficient quantity of random numbers before the seed changes.  The reseeding is done using a truly random number (computers periodically "collect" these from events such as CPU temperatures and keystroke timings).
 ===UnNetHack===

← Older revision		Revision as of 18:53, 25 May 2021
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	[[Category:Strategy]]		[[Category:Strategy]]
		+	[[Category:Development]]
	{{nethack-343}}		{{nethack-343}}

@@ Line 14: / Line 14: @@
 It was found by Adeon that a sufficiently determined player can find the seed of RNG after starting the game and then use it to his or her advantage - [https://s3.amazonaws.com/altorg/dumplog/Adeon/1236028477.nh343.txt for example to gain unlimited number of wishes from a fountain]. For demonstration see his ttyrecs on NAO from 2009-02-28 (starting with http://alt.org/nethack/trd/?file=http://alt.org/nethack/userdata/A/Adeon/ttyrec/2009-02-28.10:31:15.ttyrec.bz2#). See also Sartak's blog entry ''[http://web.archive.org/web/20090306103017/http://taeb-nethack.blogspot.com/2009/03/predicting-and-controlling-nethacks.html Predicting and controlling NetHack's randomness]'' and ais523's description of a [http://gitorious.org/nethack-tas-tools/mainline/blobs/master/turnbyturn.txt#line1657 game relying on extreme RNG manipulation].
-Instead of taking the current time in seconds as seed, NAO has after this exploits been [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/hacklib.c#L480 changed to read the seed from the operating system's own pseudorandom number generator '/dev/urandom']. This way the seed has become unpredictable.
+Instead of taking the current time in seconds as seed, NAO has after this exploit been [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/hacklib.c#L480 changed to read the seed from the operating system's own pseudorandom number generator '/dev/urandom']. This way the seed has become unpredictable.
 To also complicate the deducing of the random number generator's internal state, [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/rnd.c#L21 periodic reseeding has been implemented].

@@ Line 11: / Line 11: @@
 ==Misuse==
-It was found recently by a player named Adeon that a sufficiently determined player can find the seed of RNG after starting the game and then use it to his or her advantage - [https://s3.amazonaws.com/altorg/dumplog/Adeon/1236028477.nh343.txt for example to gain unlimited number of wishes from a fountain]. For demonstration see his ttyrecs on NAO from 2009-02-28 (starting with http://alt.org/nethack/trd/?file=http://alt.org/nethack/userdata/A/Adeon/ttyrec/2009-02-28.10:31:15.ttyrec.bz2#). See also Sartak's blog entry ''[http://web.archive.org/web/20090306103017/http://taeb-nethack.blogspot.com/2009/03/predicting-and-controlling-nethacks.html Predicting and controlling NetHack's randomness]'' and ais523's description of a [http://gitorious.org/nethack-tas-tools/mainline/blobs/master/turnbyturn.txt#line1657 game relying on extreme RNG manipulation].
+===3.4.3===
 Instead of taking the current time in seconds as seed, NAO has after this exploits been [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/hacklib.c#L480 changed to read the seed from the operating system's own pseudorandom number generator '/dev/urandom']. This way the seed has become unpredictable.
@@ Line 17: / Line 18: @@
 To also complicate the deducing of the random number generator's internal state, [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/rnd.c#L21 periodic reseeding has been implemented].
 The player nht produced a [https://ascension.run/history/unn/users/unnht/dumps/eu/unnht.1429442870.txt.html 363 turns, 16 seconds set seed UnNetHack ascension] by [https://www.reddit.com/r/nethack/comments/31ifi4/prelude_to_an_unnethack_speedrun_set_seed_gametime/cq3z2xt/ exploiting a known bug]. Nht gave detailed report on this ascension in a [https://www.reddit.com/r/nethack/comments/3355z6/363_turn_16_second_set_seed_unnethack_win/ reddit post].
 [[Category:Strategy]]
 {{nethack-343}}

@@ Line 16: / Line 16: @@
 To also complicate the deducing of the random number generator's internal state, [https://github.com/altorg/NetHack/blob/3.4.3-nao/src/rnd.c#L21 periodic reseeding has been implemented].
 [[Category:Strategy]]
 {{nethack-343}}

← Older revision		Revision as of 21:38, 20 December 2015
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	[[Category:Strategy]]		[[Category:Strategy]]
		+	{{nethack-343}}