207 lines
95 KiB
Plaintext
207 lines
95 KiB
Plaintext
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rust
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y #rustc 1.96.0 (ac68faa20 2026-05-25)ÁÀ뉊 ]!ÜÛê(¹Þ—šên -5be7b69c3ff7b5b8Á íàÄTËŸ ÜJîÄ)'ß\¥! -3d1337db07d0b3aeÁ ¤²XctÔ'ÐÓ©z¨É½Ó -a4945860e1c53b00Á ¤°ð ¾ä-±($²ï=©Ã -7e98a21bfd32b0edÁ–�òÖÀH•‘P IÓHã#£ -055f30b747f859b6Á rustc_std_workspace_coreÁCçß^ò½èÝ$Çÿ+Cé -c4878ee60b2242c9Á ŸÃï+Ñ]ŠqB<ÏïW# -8dd1dd90e70d0b6aÁ miniz_oxideÁ€š»J(P>àö÷g\K -1eb618da2918ab7fÁ adler2ÁÆ;+Þ®5¥ÌýÝ°¦ÛLˆ -f7919172d268e069Á hashbrownÁPäV9ÒÆèÜ�"ÊÖVŽ\ -0fc2184a5da6723aÁ rustc_std_workspace_allocÁs&ØòØy¯s•bæ!‰ýŠ -97e4bf30be240674Á
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std_detectÁhŠBîÙºÌI®Ë�Å�š -9dbbf8346ba7ac8bÁ rustc_demangleÁûë9´Ç×@Œ�’ùXFº -f33013f239bf9f14Á cfg_ifÁÜLh�ž§Œaã¯>� -0a71c8f33a838301Á addr2lineÁ׎Þ!]8V$É@@T· -e618e6be60e87ba2Á gimliÁ¸
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°µ~Î1‹Ñt ðÁ€w -1f7768a68858f670Á objectÁ
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áPÃ?À¶¼QHJ¥� -914cd6a4dbe590d1Á memchrÁ›º«8Ór2Ù $¨ûib‚ -cf21ca6f2bb15dcdÁë
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‹ás «LÖ€îâƒ×ɯŒ -ee6f3747e38367f0Á rand_coreÁÌý¦î—W‹œ]TewÉ: -802030763b7da6caÁ getrandomÁ’ú§‰, iMjã¸íçG‡ -3af6da94d21ddbadÁ ®f©¾/ô)c§{õa“â‘ -a3906971a93fd1b8Á –æ\‹±Ôcd�-»ùÀTƒ -f86f80b348d33b13Á
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ppv_lite86Á<<rîd”Û Jøƒ¨x7qï -b7bc7268307ccbaaÁ zerocopyÁ{£F™8ù£´ÉÒ6ñ°i -37880aa70dfe9a6cÁ DeserializeÁ\Î » serdeÁŒ® DeserializerÁdÛ »ö "$ SerializeÁLé »ö ?A
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SerializerÁTô »ö ]_‚$¯h ‚ $¤h % add_posÁ<”í bigÁ¬ù% d0123Á,¹í† ¬ž€ß X�Z »ö ˆãY €¥
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HœZ »ö Ãß X�Z »ö ˆãY Ã¥
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HœZ »ö †ß X �Z »ö ˆ ãY †¥
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H œZ »ö À chachaÁ
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BUF_BLOCKSÁ BLOCK_WORDSÁ Array64Á
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¥ ˆ ¥ ¥ É ¥ as_mutÁ ¥ ƒ !¥ !× chacha_implÁ gutsÁ % %%%%%%%%% %
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% % %
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% BLOCKÁ % BLOCK64Á % LOG2_BUFBLOCKSÁ % BUFBLOCKSÁ % BUFSZ64Á % BUFSZÁ % STREAM_PARAM_NONCEÁ % STREAM_PARAM_BLOCKÁ % roundÁ <§ % diagonalizeÁ >§ %
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undiagonalizeÁ @§ % Bæ C B refill4Á E B
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set_block_posÁ B
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get_block_posÁ B set_nonceÁ B get_nonceÁ B get_seedÁ K %ó
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M MachÁ %“ OÎ % refill_wide_implÁ QÎ Q %
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read_u32leÁ ChaChaRngÁ
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ChaChaCoreÁ > _× a› a ResultsÁ a generateÁ e SeedÁ f e from_seedÁ h k” l k£
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o next_u32Á o next_u64Á o
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fill_bytesÁ s get_word_posÁ s set_word_posÁ s
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set_streamÁ s
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get_streamÁ s´ x
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{÷ }�
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abstract20Á € �÷ €ƒ÷ „ ChaCha20CoreÁ †º ˆƒ ‹� �Ö ChaCha20RngÁ � rngÁ ‘ƒ “× €ì • seedÁ – • streamÁ • word_posÁ €š× €€�� €ŸÖ ¢× ¤› ¤ó ¤� ¨” © ¨£ « ®” ¯ ®£ ²Õ ²ä ²ó ¶ˆ ¶› ¶® ¶¿ ¶´ » ¾÷ À�
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abstract12Á à Ä÷ ÃÆ÷ Ç ChaCha12CoreÁ ɺ !˃ "#Î� $ÐÖ ChaCha12RngÁ Òÿ %Ôƒ &Ö× ÃÌ Øª Ù Ø» ØÉ ÃÝ× ÃÃà� ÃâÖ ã 'å× (ç› çó ç� )ë” ì ë£ î *+ñ” ò ñ£ ,õÕ õä õó -ùˆ ù› ù® ù¿ ù´ þ ./�÷ 0ƒ� 1 abstract8Á † ‡÷ †‰÷ Š ChaCha8CoreÁ Œº 2Žƒ 34‘� 5“Ö
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ChaCha8RngÁ •ÿ 6—ƒ 7™× †• ›ª œ ›» ›É † × ††£� †¥Ö ¦ % ChaChaÁ ¨ ¨® ¨¯ %¬ƒ %%¯� %±Ö % StateÁ ³§ ³¬ ³ ³® ³¯ %¹§ ¹ƒ % refill_wideÁ ¼ ¼ fn_implÁ ¾Î ¾ % refill_narrow_roundsÁ ÁÉ ÂÎ % set_stream_paramÁ ÄÉ ÅÎ % get_stream_paramÁ ÇÉ ÈÎ %´ Ê ÊÉ ÌÎ Ì Ì % init_chachaÁ Ð ÐÉ ÒÎ Ò %
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È( ã ›(Ø( Ø›( ¿c›( Ø † † © ‡º àOJµ ,ñ£ Ðì„) µß„)„) ™„) ¿c„) „) ¬„) „) Ø � � ì �ÿ ÊŠÁ^¥é¾µ ¿c�* ¬�* |�* …�* é �*„) µß�*�* ™�* ¿c • • ì –ª € ˜» € ™É € §›n—4òQQ Ðì�+ µß�+�+ ™�+ é �+ 8�* é �* 8�+ Ø É É ‰ ʺ !Í%)<¤ŽX Ðì—, µß—,—, ™—, ¿c—, —, ¬—, —, Ø Ò Ò Ì Óÿ †m¯G{›Ò ¿c”- ¬”- |”- …”- é ”-—, µß”-”- ™”- ¿c Ø Ø Ì Ùª à ۻ à ÜÉ Ã ùÀïÛg¹ Ðì”. µß”.”. ™”. é ”. 8”- é ”- 8”. Ø Œ Œ Ó �º ’I u¹÷¡š Ðìª/ µßª/ª/ ™ª/ ¿cª/ ª/ ¬ª/ ª/ Ø • • • –ÿ ZÕ9Q(: ¥ ¿c§0 ¬§0 |§0 …§0 é §0ª/ µß§0§0 ™§0 ¿c › › • œª † ž» † ŸÉ † ï)y3ëG¤ Ðì§1 µß§1§1 ™§1 é §1 8§0 é §0 8§1 Ø ¨ ¨ œ © ª® «¯ ©¥9Ø¢!ç Ðì½2 µß½2½2 ™½2 Ø ³ ³ é µ¬ ¶ ·® ¸¯ Ð<2ó N«¨ § ˆ †‘ �Ë ÉÔ ÒŽ Œ— •¬ ¨¹ ³! _ †“ �š •¢ ÉÖ ÒÝ Øå Œ™ • ›Š †œ •Í Éß Ø� Œ¢ ›® ¨‹ †} �� •Î ÉÀ Òà Ø‘ Œƒ •£ ›¯ ¨� † �Ÿ •Ð É Òâ Ø“ Œ… •¥ ›± ¨a †¤ Éç Œe †k �¨ É® Òë Œñ •j † Éð Œo �² Òõ •z �½ Ò€ •{ �� •ƒ �¾ ÒÄ ØÆ Ò� •‡ ›‰ •³ €à ã Ø ¿c
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EE¬(|…é 4Á Ê8 16Á @ 64Á ì8 32Á ì8 8Á ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 8Á ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 8Á ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 16ÁdÉ ,É 4 ì8 ü©- 5 ›< à $9 4 ì8 _Á ›< 2Áœ� t’ 6 ›< @ ›< , � ›<@ 6 ›< Y + ›<i 6 ›< üö+ 7 ›< ‡ ¤ *¤ 6 ›<® 6 ›<¸ 6 ›< _Á œÂ < 5 ›<LÌ 7 ›< ' * 5 ›<( 7 ›< N ›< ü¢4 8 ›< ¼ ›< † .† 5 ›<ƒ 7 ›<š 5 ›<— 7 ›< _Á „÷ <÷ 8 ›<ì8 ü×1 9 ì8 ,ï $9 8 ›< _Á 1Á ÿ@ 0Á ì8 32Á,�
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9 ì8 F $ ì8 / 6: 9 ì8 BUFSZÁ ì8 32Á,Æ%
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9 ì8 S $ ì8 / 6: 9 ì8 BUFSZÁ ,ó.
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9 ì8 ½ % ì8 0 7; 9 ì8 BUFSZÁ Y a 9 ì8 n À | ì8 ‡ Ž’ 9 ì8 BUFSZÁ ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 32Á ì8 24Á ì8 32Á ì8 24Á¬ò È( & ›( 1 È(ì8 @ F M %\]À ÄL€ ‰dÀ É VÌ\Î Ò W©dÛ † Xì\é � YÓ \ö Œ Z• Tƒ • [üä½ üä( % The ChaCha random number generators.Á �ú ü‘B ? These are native Rust implementations of RNGs derived from theÁ üÔ- * [ChaCha stream ciphers] by D J Bernstein.Á ‚ú Œ† ## GeneratorsÁ ˜ú üœP M This crate provides 8-, 12- and 20-round variants of generators via a "core"Á üíL I implementation (of [`BlockRngCore`]), each with an associated "RNG" typeÁ üº (implementing [`RngCore`]).Á Úú üÞN K These generators are all deterministic and portable (see [Reproducibility]Á ü9 6 in the book), with testing against reference vectors.Á çú üë# ## Cryptographic (secure) usageÁ �ú ü“N K Where secure unpredictable generators are required, it is suggested to useÁ üâ6 3 [`ChaCha12Rng`] or [`ChaCha20Rng`] and to seed viaÁ ü™! [`SeedableRng::from_os_rng`].Á »ú ü¿K H See also the [Security] chapter in the rand book. The crate is providedÁ ü‹ I F "as is", without any form of guarantee, and without a security audit.Á Õ ú ìÙ ## Seeding (construction)Á ÷ ú üû K H Generators implement the [`SeedableRng`] trait. Any method may be used,Á üÇ
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M J but note that `seed_from_u64` is not suitable for usage where security isÁ ü• important. Some suggestions:Á ¶ ú üº F C 1. With a fresh seed, **direct from the OS** (implies a syscall):Á \� ```Á ü� A > # use {rand_core::SeedableRng, rand_chacha::ChaCha12Rng};Á üÏ - * let rng = ChaCha12Rng::from_os_rng();Á üý # # let _: ChaCha12Rng = rng;Á \¡
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óQ ü
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@ = 2. **From a master generator.** This could be [`rand::rng`]Á üî
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O L (effectively a fresh seed without the need for a syscall on each usage)Á ü¾= : or a deterministic generator such as [`ChaCha20Rng`].Á üüO L Beware that should a weak master generator be used, correlations may beÁ üÌ? < detectable between the outputs of its child generators.Á ŒŒ ```ignoreÁ üž: 7 let rng = ChaCha12Rng::from_rng(&mut rand::rng());Á \ÙóQ åú üé( % See also [Seeding RNGs] in the book.Á ’ú Œ– ## GenerationÁ ¨ú ü¬K H Generators implement [`RngCore`], whose methods may be used directly toÁ üø. + generate unbounded integer or byte values.Á <§ ```Á ü¯* ' use rand_core::{SeedableRng, RngCore};Á üÚ! use rand_chacha::ChaCha12Rng;Á üú ü€= : let mut rng = ChaCha12Rng::from_seed(Default::default());Á ܾ let x = rng.next_u64();Á üÚ& # assert_eq!(x, 0x53f955076a9af49b);Á <�µY ‰ú ü�N K It is often more convenient to use the [`rand::Rng`] trait, which providesÁ üÜL I further functionality. See also the [Random Values] chapter in the book.Á ©ú ü9 6 [ChaCha stream ciphers]: https://cr.yp.to/chacha.htmlÁ üçK H [Reproducibility]: https://rust-random.github.io/book/crate-reprod.htmlÁ ü³I F [Seeding RNGs]: https://rust-random.github.io/book/guide-seeding.htmlÁ üýK H [Security]: https://rust-random.github.io/book/guide-rngs.html#securityÁ üÉI F [Random Values]: https://rust-random.github.io/book/guide-values.htmlÁ ü“4 1 [`BlockRngCore`]: rand_core::block::BlockRngCoreÁ üÈ# [`RngCore`]: rand_core::RngCoreÁ üì+ ( [`SeedableRng`]: rand_core::SeedableRngÁ ü˜E B [`SeedableRng::from_os_rng`]: rand_core::SeedableRng::from_os_rngÁ üÞ? < [`rand::rng`]: https://docs.rs/rand/latest/rand/fn.rng.htmlÁ üžB ? [`rand::Rng`]: https://docs.rs/rand/latest/rand/trait.Rng.htmlÁ %https://www.rust-lang.org/favicon.icoÁ„¿ 9https://www.rust-lang.org/logos/rust-logo-128x128-blk.pngÁlî #https://rust-random.github.io/rand/Álÿ ¼ t¹ %\]Àª Ä« ‰ª É VÌ© Ò W©¨ † Xì§ � YÓ ¦ Œ Z• ¥ • ['*- #TŒ 4� ÉÒ†�Œ•€Ã†œ 4ž ¨ × ° ` BlockRngÁDÌ Å BlockRngCoreÁdÖ CryptoBlockRngÁtä
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Ï , Ó 8¸q \Ô à á < S A cryptographically secure random number generator that uses the ChaCha algorithm.Áüì V < ú Ë < \ ChaCha is a stream cipher designed by Daniel J. Bernstein[^1], that we use as an RNG. It isÁü× _ < [ an improved variant of the Salsa20 cipher family, which was selected as one of the "streamÁü¿ ^ < : ciphers suitable for widespread adoption" by eSTREAM[^2].Áü¦ = < ú ì < X ChaCha uses add-rotate-xor (ARX) operations as its basis. These are safe against timingÁüø [ < [ attacks, although that is mostly a concern for ciphers and not for RNGs. We provide a SIMDÁüÜ ^ < U implementation to support high throughput on a variety of common hardware platforms.ÁüÃ!X < ú ¤" < [ With the ChaCha algorithm it is possible to choose the number of rounds the core algorithmÁü°"^ < Y should run. The number of rounds is a tradeoff between performance and security, where 8Áü—#\ < Z rounds is the minimum potentially secure configuration, and 20 rounds is widely used as aÁüü#] < conservative choice.ÁÄâ$ < ú ƒ% < Z We use a 64-bit counter and 64-bit stream identifier as in Bernstein's implementation[^1]Áü�%] < Z except that we use a stream identifier in place of a nonce. A 64-bit counter over 64-byteÁüõ%] < Y (16 word) blocks allows 1 ZiB of output before cycling, and the stream identifier allowsÁüÛ&\ < Z 2<sup>64</sup> unique streams of output per seed. Both counter and stream are initializedÁüÀ'] < H to zero but may be set via the `set_word_pos` and `set_stream` methods.Áü¦(K < ú ú( < The word layout is:Á¼†) < ú ¦) < ```textÁ\²) < ' constant constant constant constantÁüÆ)* < # seed seed seed seedÁüù)& < …�ü¨*& < ( counter counter stream_id stream_idÁü×*+ < µY<‹+ < ú ›+ < K This implementation uses an output buffer of sixteen `u32` words, and usesÁü§+N < 3 [`BlockRng`] to implement the [`RngCore`] methods.Áüþ+6 < ú ½, < 9 [^1]: D. J. Bernstein, [*ChaCha, a variant of Salsa20*](ÁüÉ,< < $ https://cr.yp.to/chacha.html)ÁüŽ-' < ú ¾- < 3 [^2]: [eSTREAM: the ECRYPT Stream Cipher Project](ÁüÊ-6 < ( http://www.ecrypt.eu.org/stream/)Áü‰.+ + ½. ¾. Ó. 8º 4¿. Å. Ò. 8d ,Æ. $ Ë. 8p ,Í. 8 Ý. 8 4á. , è. 8îq Té. ô. §/ 8ÿ ‚/ & …/ 8Àf D‡/ �/ , �/ 8¸q \‘/ œ/ $ �/ 8 $²/ 8Îg \·/ 8
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