NODE 838fd250Still more "S-1" foolishness
Matt Blaze <mab@crypto.com>Fri, 11 Aug 95 14:58:24 PDT
Here's a table of where the expanded key schedule bits come from
(I think - this could be wrong, I had to tweek some of the output
by hand). Note that some key bytes are used much more often, and
in more positions, than others, but every key byte does at least
end up being used as input to each F eventually (but not always to
each "target" byte).
Sorry for the opaque notation; this reads best when used in conjunction
with Colin's cool graph that he posted to sci.crypt last night.
-matt
| | G0 G1 F+0 F+1 F+2 F+3 (function input)
bytes| 4 5 2 3 0 1 (mixed with byte #)
rou|enc-| all all R+6L R+6H R+7L R+7H (output affects)
nd |rypt| 0 1 2 3 4 5 (key schedule byte #)
# |ed |LLHH LLHH LLHH LLHH LLHH LLHH (posn of orig key byte in sched byte)
======================================
0 76 5954 9538 5495 4851 8515 5151
1 54 1510 5194 1051 0415 4171 1717
2 32 7176 1750 7617 5071 0737 7373
3 10 3732 7316 3273 1637 6393 3939
4 67 9398 3972 9739 7293 2959 9595
5 54 5954 9538 5495 4851 8515 5151
6 32 1510 5194 1051 0415 4171 1717
7 10 7176 1750 7617 5071 0737 7373
8 76 3732 7316 3273 1637 6393 3939
9 54 9398 3972 9739 7293 2959 9595
10 32 5954 9538 5495 4851 8515 5151 (original key bytes used)
11 10 1510 5194 1051 0415 4171 1717
12 76 7176 1750 7617 5071 0737 7373
13 54 3732 7316 3273 1637 6393 3939
14 32 9398 3972 9739 7293 2959 9595
15 10 5954 9538 5495 4851 8515 5151
16 76 1510 5194 1051 0415 4171 1717
17 54 7176 1750 7617 5071 0737 7373
18 32 3732 7316 3273 1637 6393 3939
19 10 9398 3972 9739 7293 2959 9595
20 76 5954 9538 5495 4851 8515 5151
21 54 1510 5194 1051 0415 4171 1717
22 32 7176 1750 7617 5071 0737 7373
23 10 3732 7316 3273 1637 6393 3939
24 76 9398 3972 9739 7293 2959 9595
25 54 5954 9538 5495 4851 8515 5151
26 32 1510 5194 1051 0415 4171 1717
27 10 7176 1750 7617 5071 0737 7373
28 76 3732 7316 3273 1637 6393 3939
29 54 9398 3972 9739 7293 2959 9595
30 32 5954 9538 5495 4851 8515 5151
31 10 1510 5194 1051 0415 4171 1717
NODE 8822451eRe: Still more "S-1" foolishness
Matt Blaze <mab@crypto.com>Sat, 12 Aug 95 10:30:21 PDT
I wrote:
>Here's a table of where the expanded key schedule bits come from
>(I think - this could be wrong, I had to tweek some of the output
>by hand). Note that some key bytes are used much more often, and
>in more positions, than others, but every key byte does at least
>end up being used as input to each F eventually (but not always to
>each "target" byte).
>
>Sorry for the opaque notation; this reads best when used in conjunction
>with Colin's cool graph that he posted to sci.crypt last night.
>
Whoops - there was a bug in my understanding of what was going on
that conspired with a bug in my table generation program to make everything
wrong. Here's the correct table, for those interested. Sorry for the noise.
-matt
R | | G0 G1 F+0 F+1 F+2 F+3 (this key byte is input to this fn)
O bytes| R+4 R+5 R+2 R+3 R+0 R+1 (key byte is mixed with this block byte)
U |enc-| all all R+6L R+6H R+7L R+7H (output affects this byte)
N |rypt| 0 1 2 3 4 5 (key schedule byte #)
D |ed |LLHH LLHH LLHH LLHH LLHH LLHH (posn of orig key byte in sched byte)
======================================
0 76 5831 9425 5362 4738 8492 5038
1 10 1497 5081 1928 0394 4058 1694
2 32 7053 1647 7584 6950 0614 7250
3 54 3619 7203 3140 2516 6270 3816
4 76 9275 3869 9706 8172 2836 9472
5 10 5831 9425 5362 4738 8492 5038
6 32 1497 5081 1928 0394 4058 1694
7 54 7053 1647 7584 6950 0614 7250
8 76 3619 7203 3140 2516 6270 3816
9 10 9275 3869 9706 8172 2836 9472
10 32 5831 9425 5362 4738 8492 5038 (number indicates position in schedule
11 54 1497 5081 1928 0394 4058 1694 of original key bytes; an entry
12 76 7053 1647 7584 6950 0614 7250 "5678" means key bytes 5 and 6 are
13 10 3619 7203 3140 2516 6270 3816 in the low order position of this
14 32 9275 3869 9706 8172 2836 9472 schedule entry and bytes 7 and 8
15 54 5831 9425 5362 4738 8492 5038 are in the high order position. Bytes
16 76 1497 5081 1928 0394 4058 1694 are first run through an F functuon
17 10 7053 1647 7584 6950 0614 7250 and XORd with each other to create
18 32 3619 7203 3140 2516 6270 3816 the schedule nibble.)
19 54 9275 3869 9706 8172 2836 9472
20 76 5831 9425 5362 4738 8492 5038
21 10 1497 5081 1928 0394 4058 1694
22 32 7053 1647 7584 6950 0614 7250
23 54 3619 7203 3140 2516 6270 3816
24 76 9275 3869 9706 8172 2836 9472
25 10 5831 9425 5362 4738 8492 5038
26 32 1497 5081 1928 0394 4058 1694
27 54 7053 1647 7584 6950 0614 7250
28 76 3619 7203 3140 2516 6270 3816
29 10 9275 3869 9706 8172 2836 9472
30 32 5831 9425 5362 4738 8492 5038
31 54 1497 5081 1928 0394 4058 1694