1	# mode-core on its own: a block's hex and byte forms, XOR, the round-trip
2	# hypothesis over a toy permutation, and the refusal of a byte string that
3	# is not 16 bytes. The modes' own packages test the modes.
4	import Base
5	import bend-osdev-bytes@0.1.1.0/bytes.bend as B
6	import ./mode_core.bend as M
7	
8	# A toy permutation of blocks, NOT a cipher: the words rotated, then XOR
9	# with the key block. Enough to run the mode's code paths (encryption and
10	# decryption differ, so mixing them up shows); the mode is tested against
11	# its specification over AES in bend-osdev-aes-modes (the specifications'
12	# vectors) and in ref/ (against Python's cryptography).
13	def toy.rot(b: M.CmBlock) -> M.CmBlock:
14	  match b:
15	    case M.CmBlock{w0, w1, w2, w3}:
16	      M.CmBlock{w1, w2, w3, w0}
17	
18	def toy.unrot(b: M.CmBlock) -> M.CmBlock:
19	  match b:
20	    case M.CmBlock{w0, w1, w2, w3}:
21	      M.CmBlock{w3, w0, w1, w2}
22	
23	def toy.enc(k: M.CmBlock, b: M.CmBlock) -> M.CmBlock:
24	  M.CmBlock.xor(k, toy.rot(b))
25	
26	def toy.dec(k: M.CmBlock, c: M.CmBlock) -> M.CmBlock:
27	  toy.unrot(M.CmBlock.xor(k, c))
28	
29	def key() -> M.CmBlock:
30	  M.CmBlock{19088743, 2309737967, 4275878552, 1985229328}
31	
32	def key2() -> M.CmBlock:
33	  M.CmBlock{2882400001, 305419896, 3735928559, 4027432973}
34	
35	def hexs(bs: List<&2, M.CmBlock>) -> String:
36	  match bs:
37	    case Nil{}:
38	      ""
39	    case Con{b, t}:
40	      M.CmBlock.hex(b) ++ hexs(t)
41	
42	def maybe(m: Maybe<&2, M.CmBlock>) -> String:
43	  match m:
44	    case None{}:
45	      "none"
46	    case Some{b}:
47	      M.CmBlock.hex(b)
48	
49	def main() -> IO(Unit):
50	  +b : M.CmBlock = M.CmBlock{1122867, 1146447479, 2291772091, 3437096703}
51	  do IO<Unit>:
52	    IO.print("zero " ++ M.CmBlock.hex(M.CmBlock.zero()))
53	    IO.print("block " ++ M.CmBlock.hex(b))
54	    IO.print("xor " ++ M.CmBlock.hex(M.CmBlock.xor(b, key())))
55	    IO.print("to_octets " ++ B.Octets.hex(M.CmBlock.to_octets(b)))
56	    IO.print("of_octets " ++ maybe(M.CmBlock.of_octets(M.CmBlock.to_octets(b))))
57	    IO.print("of_octets_15 " ++ maybe(M.CmBlock.of_octets(B.Octets.of_list([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]))))
58	    IO.print("dec_enc " ++ hexs(M.CmBlock.dec_enc(~M.CmBlock, ~toy.enc, ~toy.dec, key(), [b, key(), M.CmBlock.zero()])))
59	
60	#|zero 00000000000000000000000000000000
61	#|block 00112233445566778899aabbccddeeff
62	#|xor 01326754cdfeab9876451023ba89dcef
63	#|to_octets 00112233445566778899aabbccddeeff
64	#|of_octets 00112233445566778899aabbccddeeff
65	#|of_octets_15 none
66	#|dec_enc 00112233445566778899aabbccddeeff0123456789abcdeffedcba987654321000000000000000000000000000000000