# 3f: scrambling ### `++ob` Reversible scrambling core, v2 ++ ob |% A core for performing reversible scrambling operations for the `@p` phonetic base. ------------------------------------------------------------------------ ### `++feen` Conceal structure, v2 Randomly permutes atoms that fit into 17 to 32 bits into one another. If the atom fits into 33 to 64 bits, does the same permutation on the low 32 bits only. Otherwise, passes the atom through unchanged. Accepts ------- An atom. Produces -------- An atom. Source ------ ++ feen :: conceal structure v2 |= pyn/@ ^- @ ?: &((gte pyn 0x1.0000) (lte pyn 0xffff.ffff)) (add 0x1.0000 (fice (sub pyn 0x1.0000))) ?: &((gte pyn 0x1.0000.0000) (lte pyn 0xffff.ffff.ffff.ffff)) =+ lo=(dis pyn 0xffff.ffff) =+ hi=(dis pyn 0xffff.ffff.0000.0000) %+ con hi (add 0x1.0000 (fice (sub lo 0x1.0000))) pyn :: Examples -------- XX ------------------------------------------------------------------------ ### `++fend` XX Randomly permutes atoms that fit into 17 to 32 bits into one another, and randomly permutes the low 32 bits of atoms that fit into 33 to 64 bits; otherwise, passes the atom through unchanged. The permutation is the inverse of the one applied by `++feen`. Accepts ------- An atom. Produces -------- An atom. Source ------ ++ fend :: restore structure v2 |= cry/@ ^- @ ?: &((gte cry 0x1.0000) (lte cry 0xffff.ffff)) (add 0x1.0000 (teil (sub cry 0x1.0000))) ?: &((gte cry 0x1.0000.0000) (lte cry 0xffff.ffff.ffff.ffff)) =+ lo=(dis cry 0xffff.ffff) =+ hi=(dis cry 0xffff.ffff.0000.0000) %+ con hi (add 0x1.0000 (teil (sub lo 0x1.0000))) cry :: Examples -------- ------------------------------------------------------------------------ ### `++fice` XX Accepts ------- An atom. Produces -------- An atom. Source ------ ++ fice :: adapted from |= nor/@ :: black and rogaway ^- @ :: "ciphers with =+ ^= sel :: arbitrary finite %+ rynd 2 :: domains", 2002 %+ rynd 1 %+ rynd 0 [(mod nor 65.535) (div nor 65.535)] (add (mul 65.535 -.sel) +.sel) :: Examples -------- ------------------------------------------------------------------------ ### `++teil` XX Applies the reverse of the Feistel-like cipher applied by `++fice`. Unlike a conventional Feistel cipher that is its own inverse if keys are used in reverse order, this Feistel-like cipher uses two moduli that must be swapped when applying the reverse transformation. Accepts ------- An atom. Produces -------- An atom. Source ------ ++ teil :: reverse ++fice |= vip/@ ^- @ =+ ^= sel %+ rund 0 %+ rund 1 %+ rund 2 [(mod vip 65.535) (div vip 65.535)] (add (mul 65.535 -.sel) +.sel) :: Examples -------- ------------------------------------------------------------------------ ### `++rynd` XX A single round of the Feistel-like cipher `++fice`. AES (`++aesc`) is used as the round function. Accepts ------- A cell of three atoms, `n`, `l`, and `r`. Produces -------- A cell of two atoms. Source ------ ++ rynd :: feistel round |= [n/@ l/@ r/@] ^- [@ @] :- r ?~ (mod n 2) (~(sum fo 65.535) l (en:aesc (snag n raku) r)) (~(sum fo 65.536) l (en:aesc (snag n raku) r)) Examples -------- ------------------------------------------------------------------------ ### `++rund` XX A single round of the Feistel-like reverse cipher `++teil`. Accepts ------- A cell of three atoms, `n`, `l`, and `r`. Produces -------- A cell of two atoms. Source ------ ++ rund :: reverse round |= {n/@ l/@ r/@} ^- {@ @} :- r ?~ (mod n 2) (~(dif fo 65.535) l (en:aesc (snag n raku) r)) (~(dif fo 65.536) l (en:aesc (snag n raku) r)) Examples -------- ------------------------------------------------------------------------ ### `++raku` XX Accepts ------- A list of atoms of odor `@ux` (hexadecimal). Produces -------- Arbitrary keys for use with `++aesc`. Source ------ ++ raku ^- (list ,@ux) :~ 0x15f6.25e3.083a.eb3e.7a55.d4db.fb99.32a3. 43af.2750.219e.8a24.e5f8.fac3.6c36.f968 0xf2ff.24fe.54d0.1abd.4b2a.d8aa.4402.8e88. e82f.19ec.948d.b1bb.ed2e.f791.83a3.8133 0xa3d8.6a7b.400e.9e91.187d.91a7.6942.f34a. 6f5f.ab8e.88b9.c089.b2dc.95a6.aed5.e3a4 == Examples -------- *** ### `++un` Reversible scrambling core ++ un :: =(x (wred (wren x))) |% A core that contains arms that perform reversible scrambling operations. Used in the `@p` phonetic base. ------------------------------------------------------------------------ ### `++wren` Conceal structure Scrambles a bytestring `pyn` by adding the current position to each byte, looking it up in an s-box, and then performing the XOR operation on the result, pushing it forward. Produces an atom. Accepts ------- `pyn` is an atom. Produces -------- An atom. Source ------ ++ wren :: conceal structure |= pyn/@ ^- @ =+ len=(met 3 pyn) ?: =(0 len) 0 => .(len (dec len)) =+ mig=(zaft (xafo len (cut 3 [len 1] pyn))) %+ can 3 %- flop ^- (list {@ @}) :- [1 mig] |- ^- (list {@ @}) ?: =(0 len) ~ => .(len (dec len)) =+ mog=(zyft :(mix mig (end 3 1 len) (cut 3 [len 1] pyn))) [[1 mog] $(mig mog)] :: Examples -------- > `@ux`(wren:un 'testing') 0x30.bf6a.b9fe.7d8f > `@ux`'testing' 0x67.6e69.7473.6574 > `@da`(wred:un (wren:un ~2001.2.5)) ~2001.2.5 ------------------------------------------------------------------------ ### `++wred` Restore structure Unscrambles a bytestring `cry` by subtracting the current position from each byte, looking it up in an s-box, and performing the XOR operation on the result, pushing it forward. Produces an atom. Accepts ------- `cry` is an atom. Produces -------- Source ------ ++ wred :: restore structure |= cry/@ ^- @ =+ len=(met 3 cry) ?: =(0 len) 0 => .(len (dec len)) =+ mig=(cut 3 [len 1] cry) %+ can 3 %- flop ^- (list {@ @}) :- [1 (xaro len (zart mig))] |- ^- (list {@ @}) ?: =(0 len) ~ => .(len (dec len)) =+ mog=(cut 3 [len 1] cry) [[1 :(mix mig (end 3 1 len) (zyrt mog))] $(mig mog)] :: Examples -------- > (wred:un 0x30.bf6a.b9fe.7d8f) 29.113.321.805.538.676 > `@t`(wred:un 0x30.bf6a.b9fe.7d8f) 'testing' > (wred:un (wren:un 200.038.426)) 200.038.426 ------------------------------------------------------------------------ ### `++xafo` Add modulo 255 Produces the sum of two atoms modulo 255, encoded as a nonzero byte. Accepts ------- A cell of two atoms, `a` and `b`. Source ------ ++ xafo |=([a/@ b/@] +((mod (add (dec b) a) 255))) Examples -------- > (xafo:un 5 6) 11 > (xafo:un 256 20) 21 ------------------------------------------------------------------------ ### `++xaro` Subtract modulo 255 Produces the difference between two atoms modulo 255, encoded as a nonzero byte. Accepts ------- A cell of two atoms, `a` and `b`. Produces -------- An atom. Source ------ ++ xaro |=([a/@ b/@] +((mod (add (dec b) (sub 255 (mod a 255))) 255))) Examples -------- > (xaro:un 17 57) 40 > (xaro:un 265 12) 2 ------------------------------------------------------------------------ ### `++zaft` Look up in 255 sub box The inverse of `++zart`. Looks up a nonzero byte `a`in a substiution box with 255 values, producing a unique nonzero byte. Accepts ------- `a` is an atom of one byte in length. Produces -------- An atom. Source ------ ++ zaft :: forward 255-sbox |= a/@D =+ ^= b 0xcc.75bc.86c8.2fb1.9a42.f0b3.79a0.92ca.21f6.1e41.cde5.fcc0. 7e85.51ae.1005.c72d.1246.07e8.7c64.a914.8d69.d9f4.59c2.8038. 1f4a.dca2.6fdf.66f9.f561.a12e.5a16.f7b0.a39f.364e.cb70.7318. 1de1.ad31.63d1.abd4.db68.6a33.134d.a760.edee.5434.493a.e323. 930d.8f3d.3562.bb81.0b24.43cf.bea5.a6eb.52b4.0229.06b2.6704. 78c9.45ec.d75e.58af.c577.b7b9.c40e.017d.90c3.87f8.96fa.1153. 0372.7f30.1c32.ac83.ff17.c6e4.d36d.6b55.e2ce.8c71.8a5b.b6f3. 9d4b.eab5.8b3c.e7f2.a8fe.9574.5de0.bf20.3f15.9784.9939.5f9c. e609.564f.d8a4.b825.9819.94aa.2c08.8e4c.9b22.477a.2840.3ed6. 3750.6ef1.44dd.89ef.6576.d00a.fbda.9ed2.3b6c.7b0c.bde9.2ade. 5c88.c182.481a.1b0f.2bfd.d591.2726.57ba (cut 3 [(dec a) 1] b) :: Examples -------- > (zaft:un 0x12) 42 > (zaft:un 0xff) 204 > (zaft:un 0x0) ! decrement-underflow ! exit ------------------------------------------------------------------------ ### `++zart` Reverse look up in 255 sub box The inverse of `++zaft`. Looks up the index of a nonzero byte `a` in the substitution box with 255 values, producing a unique nonzero byte. Accepts ------- `a` is an atom of one byte in length. Produces -------- An atom. Source ------ ++ zart :: reverse 255-sbox |= a/@D =+ ^= b 0x68.4f07.ea1c.73c9.75c2.efc8.d559.5125.f621.a7a8.8591.5613. dd52.40eb.65a2.60b7.4bcb.1123.ceb0.1bd6.3c84.2906.b164.19b3. 1e95.5fec.ffbc.f187.fbe2.6680.7c77.d30e.e94a.9414.fd9a.017d. 3a7e.5a55.8ff5.8bf9.c181.e5b6.6ab2.35da.50aa.9293.3bc0.cdc6. f3bf.1a58.4130.f844.3846.744e.36a0.f205.789e.32d8.5e54.5c22. 0f76.fce7.4569.0d99.d26e.e879.dc16.2df4.887f.1ffe.4dba.6f5d. bbcc.2663.1762.aed7.af8a.ca20.dbb4.9bc7.a942.834c.105b.c4d4. 8202.3e61.a671.90e6.273d.bdab.3157.cfa4.0c2e.df86.2496.f7ed. 2b48.2a9d.5318.a343.d128.be9c.a5ad.6bb5.6dfa.c5e1.3408.128d. 2c04.0339.97a1.2ff0.49d0.eeb8.6c0a.0b37.b967.c347.d9ac.e072. e409.7b9f.1598.1d3f.33de.8ce3.8970.8e7a (cut 3 [(dec a) 1] b) :: Examples -------- > `@ux`(zart:un 204) 0xff > `@ux`(zart:un 42) 0x12 ------------------------------------------------------------------------ ### `++zyft` Lookup byte in 256 sub box The inverse of `++zyrt`. Looks up a byte `a` in a substituion box with 256 values, producing a byte. Accepts ------- `a` is an atom of one byte in length. Produces -------- An atom. Source ------ ++ zyft :: forward 256-sbox |= a/@D =+ ^= b 0xbb49.b71f.b881.b402.17e4.6b86.69b5.1647.115f.dddb.7ca5. 8371.4bd5.19a9.b092.605d.0d9b.e030.a0cc.78ba.5706.4d2d. 986a.768c.f8e8.c4c7.2f1c.effe.3cae.01c0.253e.65d3.3872. ce0e.7a74.8ac6.daac.7e5c.6479.44ec.4143.3d20.4af0.ee6c. c828.deca.0377.249f.ffcd.7b4f.eb7d.66f2.8951.042e.595a. 8e13.f9c3.a79a.f788.6199.9391.7fab.6200.4ce5.0758.e2f1. 7594.c945.d218.4248.afa1.e61a.54fb.1482.bea4.96a2.3473. 63c2.e7cb.155b.120a.4ed7.bfd8.b31b.4008.f329.fca3.5380. 9556.0cb2.8722.2bea.e96e.3ac5.d1bc.10e3.2c52.a62a.b1d6. 35aa.d05e.f6a8.0f3b.31ed.559d.09ad.f585.6d21.fd1d.8d67. 370b.26f4.70c1.b923.4684.6fbd.cf8b.5036.0539.9cdc.d93f. 9068.1edf.8f33.b632.d427.97fa.9ee1 (cut 3 [a 1] b) :: Examples -------- > (zyft:un 0x12) 57 > (zyft:un 0x0) 225 > (zyft:un 0xff) 187 ------------------------------------------------------------------------ ### `++zyrt` Reverse lookup byte in 256 sub box The inverse of `++zyft`. Looks up a byte `a` in a substituion box with 256 values, producing a byte. Accepts ------- `a` is an atom of one byte in length. Produces -------- An atom. Source ------ ++ zyrt :: reverse 256-sbox |= a/@D =+ ^= b 0x9fc8.2753.6e02.8fcf.8b35.2b20.5598.7caa.c9a9.30b0.9b48. 47ce.6371.80f6.407d.00dd.0aa5.ed10.ecb7.0f5a.5c3a.e605. c077.4337.17bd.9eda.62a4.79a7.ccb8.44cd.8e64.1ec4.5b6b. 1842.ffd8.1dfb.fd07.f2f9.594c.3be3.73c6.2cb6.8438.e434. 8d3d.ea6a.5268.72db.a001.2e11.de8c.88d3.0369.4f7a.87e2. 860d.0991.25d0.16b9.978a.4bf4.2a1a.e96c.fa50.85b5.9aeb. 9dbb.b2d9.a2d1.7bba.66be.e81f.1946.29a8.f5d2.f30c.2499. c1b3.6583.89e1.ee36.e0b4.6092.937e.d74e.2f6f.513e.9615. 9c5d.d581.e7ab.fe74.f01b.78b1.ae75.af57.0ec2.adc7.3245. 12bf.2314.3967.0806.31dc.cb94.d43f.493c.54a6.0421.c3a1. 1c4a.28ac.fc0b.26ca.5870.e576.f7f1.616d.905f.ef41.33bc. df4d.225e.2d56.7fd6.1395.a3f8.c582 (cut 3 [a 1] b) Examples -------- > `@ux`(zyrt:un 57) 0x12 > `@ux`(zyrt:un 225) 0x0 > `@ux`(zyrt:un 187) 0xff ***