"Eric Biggers" <ebiggers@xxxxxxxxxx> wrote:
> On Mon, Apr 15, 2024 at 10:41:07PM +0200, Stefan Kanthak wrote:
[...]
>> At last the final change: write the macro straightforward and SIMPLE,
>> closely matching NIST.FIPS.180-4.pdf and their order of operations.
>>
>> @@ ...
>> +.macro sha256 m0 :req, m1 :req, m2 :req, m3 :req
>> +.if \@ < 4
>> + movdqu \@*16(DATA_PTR), \m0
>> + pshufb SHUF_MASK, \m0 # \m0 = {w(\@*16), w(\@*16+1), w(\@*16+2), w(\@*16+3)}
>> +.else
>> + # \m0 = {w(\@*16-16), w(\@*16-15), w(\@*16-14), w(\@*16-13)}
>> + # \m1 = {w(\@*16-12), w(\@*16-11), w(\@*16-10), w(\@*16-9)}
>> + # \m2 = {w(\@*16-8), w(\@*16-7), w(\@*16-6), w(\@*16-5)}
>> + # \m3 = {w(\@*16-4), w(\@*16-3), w(\@*16-2), w(\@*16-1)}
>> + sha256msg1 \m1, \m0
>> + movdqa \m3, TMP
>> + palignr $4, \m2, TMP
>> + paddd TMP, \m0
>> + sha256msg2 \m3, \m0 # \m0 = {w(\@*16), w(\@*16+1), w(\@*16+2), w(\@*16+3)}
>> +.endif
>> + movdqa (\@-8)*16(SHA256CONSTANTS), MSG
>> + paddd \m0, MSG
>> + sha256rnds2 STATE0, STATE1 # STATE1 = {f', e', b', a'}
>> + punpckhqdq MSG, MSG
>> + sha256rnds2 STATE1, STATE0 # STATE0 = {f", e", b", a"},
>> + # STATE1 = {h", g", d", c"}
>> +.endm
>>
>> JFTR: you may simplify this further using .altmacro and generate \m0 to \m3
>> as MSG%(4-\@&3), MSG%(5-\@&3), MSG%(6-\@&3) and MSG%(7-\@&3) within
>> the macro, thus getting rid of its 4 arguments.
>>
>> @@ ...
>> +.rept 4 # 4*4*4 rounds
>> + sha256 MSG0, MSG1, MSG2, MSG3
>> + sha256 MSG1, MSG2, MSG3, MSG0
>> + sha256 MSG2, MSG3, MSG0, MSG1
>> + sha256 MSG3, MSG0, MSG1, MSG2
>> +.endr
>
> Could you please send a real patch, following
> Documentation/process/submitting-patches.rst? It's hard to understand what
> you're proposing here.
1) I replace your macro (which unfortunately follows Tim Chens twisted code)
COMPLETELY with a clean and simple implementation: message schedule first,
update of state variables last.
You don't need ".if \i >= 12 && \i < 60"/".if \i >= 4 && \i < 52" at all!
2) I replace the .irp which invokes your macro with a .rept: my macro uses \@
instead of an argument for the round number.
<https://sourceware.org/binutils/docs/as.html#Macro>
| \@
| as maintains a counter of how many macros it has executed in this pseudo-
| variable; you can copy that number to your output with '\@', but only
| within a macro definition.
That's all.
regards
Stefan
