1276 lines
39 KiB
PHP
1276 lines
39 KiB
PHP
; mpint.inc - Multi precision integer procedures
|
|
;
|
|
; Copyright (C) 2015-2024 Jeffrey Amelynck
|
|
;
|
|
; This program is free software: you can redistribute it and/or modify
|
|
; it under the terms of the GNU General Public License as published by
|
|
; the Free Software Foundation, either version 3 of the License, or
|
|
; (at your option) any later version.
|
|
;
|
|
; This program is distributed in the hope that it will be useful,
|
|
; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
; GNU General Public License for more details.
|
|
;
|
|
; You should have received a copy of the GNU General Public License
|
|
; along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
; Note:
|
|
;
|
|
; These procedures have been designed to work with unsigned integers.
|
|
; For compatibility reasons, the highest bit must always be 0.
|
|
;
|
|
; You have been warned!
|
|
|
|
MPINT_MAX_LEN = MAX_BITS/8
|
|
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_to_little_endian uses esi edi ecx, dst, src ;/////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Convert big endian MPINT to little endian MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to big endian MPINT ;;
|
|
;> dst = pointer to buffer for little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< eax = MPINT number length ;;
|
|
;;===========================================================================;;
|
|
|
|
mov esi, [src]
|
|
mov edi, [dst]
|
|
; Load length dword
|
|
lodsd
|
|
; Convert to little endian
|
|
bswap eax
|
|
stosd
|
|
test eax, eax
|
|
jz .zero
|
|
; Copy data, convert to little endian meanwhile
|
|
push eax
|
|
add esi, eax
|
|
dec esi
|
|
mov ecx, eax
|
|
std
|
|
@@:
|
|
lodsb
|
|
mov byte[edi], al
|
|
inc edi
|
|
dec ecx
|
|
jnz @r
|
|
|
|
cld
|
|
pop eax
|
|
.zero:
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_to_big_endian uses esi edi ecx, dst, src ;////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Convert little endian MPINT to big endian MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;> dst = pointer to buffer for big endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< eax = MPINT number length ;;
|
|
;;===========================================================================;;
|
|
|
|
mov esi, [src]
|
|
mov edi, [dst]
|
|
; Load length dword
|
|
lodsd
|
|
test eax, eax
|
|
jz .zero
|
|
mov ecx, eax
|
|
add esi, eax
|
|
dec esi
|
|
push eax ; we'll return length to the caller later
|
|
bswap eax
|
|
stosd
|
|
; Copy data, convert to big endian meanwhile
|
|
std
|
|
@@:
|
|
lodsb
|
|
mov byte[edi], al
|
|
inc edi
|
|
dec ecx
|
|
jnz @r
|
|
cld
|
|
pop eax
|
|
ret
|
|
|
|
.zero:
|
|
stosd ; Number 0 has 0 data bytes
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_print uses ecx esi eax, src ;/////////////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Print MPINT to the debug board. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< - ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "0x"
|
|
mov esi, [src]
|
|
mov ecx, [esi]
|
|
test ecx, ecx
|
|
jz .zero
|
|
lea esi, [esi + ecx + 4 - 1]
|
|
pushf
|
|
std
|
|
.loop:
|
|
lodsb
|
|
DEBUGF 1, "%x", eax:2
|
|
dec ecx
|
|
jnz .loop
|
|
DEBUGF 1, "\n"
|
|
popf
|
|
|
|
ret
|
|
|
|
.zero:
|
|
DEBUGF 1, "00\n"
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_bits uses esi ecx, dst ;//////////////////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Count the number of bits in the MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< eax = highest order bit number + 1 ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_bits(0x%x): ", [dst]
|
|
|
|
mov esi, [dst]
|
|
mov eax, [esi]
|
|
test eax, eax
|
|
jz .zero
|
|
add esi, 4-1
|
|
; Find highest order byte
|
|
.byteloop:
|
|
cmp byte[esi+eax], 0
|
|
jne .nz
|
|
dec eax
|
|
jnz .byteloop
|
|
.zero:
|
|
DEBUGF 1, "%u\n", eax
|
|
ret
|
|
.nz:
|
|
mov cl, byte[esi+eax]
|
|
; multiply (eax - 1) by 8 to get nr of bits before this byte
|
|
dec eax
|
|
shl eax, 3
|
|
; Now shift bits of the highest order byte right, until the byte reaches zero, counting bits meanwhile
|
|
.bitloop:
|
|
inc eax
|
|
shr cl, 1
|
|
jnz .bitloop
|
|
DEBUGF 1, "%u\n", eax
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_bytes uses esi, dst ;/////////////////////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Count the number of bytes in the MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< eax = highest order byte number + 1 ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_bytes(0x%x): ", [dst]
|
|
|
|
mov esi, [dst]
|
|
mov eax, [esi]
|
|
test eax, eax
|
|
jz .done
|
|
add esi, 4-1
|
|
; Find highest order byte
|
|
.byteloop:
|
|
cmp byte[esi+eax], 0
|
|
jne .done
|
|
dec eax
|
|
jnz .byteloop
|
|
.done:
|
|
DEBUGF 1, "%u\n", eax
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_cmp uses esi edi edx ecx ebx eax, src, dst ;//////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Compare two MPINTS. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< flags are set as for single precision CMP instruction ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_cmp(0x%x, 0x%x)\n", [dst], [src]
|
|
|
|
; First, check the size of both numbers
|
|
stdcall mpint_bytes, [dst]
|
|
mov ecx, eax
|
|
stdcall mpint_bytes, [src]
|
|
; If one number has more bytes, it is bigger
|
|
cmp eax, ecx
|
|
jne .got_answer
|
|
; If both numbers have 0 bytes, they are equal
|
|
test ecx, ecx
|
|
jz .got_answer
|
|
; Numbers have equal amount of bytes
|
|
; Start comparing from the MSB towards the LSB
|
|
mov esi, [src]
|
|
mov edi, [dst]
|
|
lea esi, [esi + 4 + ecx]
|
|
lea edi, [edi + 4 + ecx]
|
|
; If remaining bytes is not divisible by 4, compare only one byte at a time
|
|
.loop_1:
|
|
test ecx, 111b
|
|
jz .done_1
|
|
dec esi
|
|
dec edi
|
|
mov al, byte[esi]
|
|
cmp al, byte[edi]
|
|
jne .got_answer
|
|
dec ecx
|
|
jmp .loop_1
|
|
; Remaining bytes is divisable by 8, compare dwords
|
|
.done_1:
|
|
shr ecx, 3
|
|
jz .got_answer
|
|
|
|
align 8
|
|
.loop_8:
|
|
lea esi, [esi-8]
|
|
lea edi, [edi-8]
|
|
mov eax, [esi+04]
|
|
mov ebx, [esi+00]
|
|
cmp eax, [edi+04]
|
|
jne .got_answer
|
|
cmp ebx, [edi+00]
|
|
jne .got_answer
|
|
dec ecx
|
|
jnz .loop_8
|
|
|
|
.got_answer:
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_mov uses esi edi edx ecx ebx eax, dst, src ;//////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Copy MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to buffer for little endian MPINT ;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = src ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_mov(0x%x, 0x%x)\n", [dst], [src]
|
|
|
|
mov esi, [src]
|
|
mov edi, [dst]
|
|
mov ecx, [esi] ; Get dword count + 1
|
|
add ecx, 7 ;
|
|
shr ecx, 2 ;
|
|
mov edx, ecx
|
|
|
|
shr ecx, 3
|
|
test ecx, ecx
|
|
jz .no32
|
|
align 8
|
|
.loop32:
|
|
mov eax, [esi+00]
|
|
mov ebx, [esi+04]
|
|
mov [edi+00], eax
|
|
mov [edi+04], ebx
|
|
|
|
mov eax, [esi+08]
|
|
mov ebx, [esi+12]
|
|
mov [edi+08], eax
|
|
mov [edi+12], ebx
|
|
|
|
mov eax, [esi+16]
|
|
mov ebx, [esi+20]
|
|
mov [edi+16], eax
|
|
mov [edi+20], ebx
|
|
|
|
mov eax, [esi+24]
|
|
mov ebx, [esi+28]
|
|
mov [edi+24], eax
|
|
mov [edi+28], ebx
|
|
|
|
lea esi, [esi+32]
|
|
lea edi, [edi+32]
|
|
dec ecx
|
|
jnz .loop32
|
|
.no32:
|
|
|
|
test edx, 100b
|
|
jz .no16
|
|
|
|
mov eax, [esi+00]
|
|
mov ebx, [esi+04]
|
|
mov [edi+00], eax
|
|
mov [edi+04], ebx
|
|
|
|
mov eax, [esi+08]
|
|
mov ebx, [esi+12]
|
|
mov [edi+08], eax
|
|
mov [edi+12], ebx
|
|
|
|
lea esi, [esi+16]
|
|
lea edi, [edi+16]
|
|
.no16:
|
|
|
|
test edx, 010b
|
|
jz .no8
|
|
|
|
mov eax, [esi+00]
|
|
mov ebx, [esi+04]
|
|
mov [edi+00], eax
|
|
mov [edi+04], ebx
|
|
|
|
lea esi, [esi+08]
|
|
lea edi, [edi+08]
|
|
.no8:
|
|
|
|
test edx, 001b
|
|
jz .no4
|
|
|
|
mov eax, [esi+00]
|
|
mov [edi+00], eax
|
|
.no4:
|
|
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_shl1 uses edi ecx, dst ;//////////////////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Shift little endian MPINT one bit to the left. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = dst SHL 1 ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_shl1(0x%x)\n", [dst]
|
|
|
|
mov edi, [dst]
|
|
mov ecx, [edi]
|
|
test ecx, 11b
|
|
jnz .adjust_needed
|
|
shr ecx, 2
|
|
jz .done
|
|
|
|
.length_ok:
|
|
add edi, 4
|
|
; Do the lowest order dword first
|
|
shl dword[edi], 1
|
|
lea edi, [edi+4]
|
|
dec ecx
|
|
jz .done
|
|
; And the remaining dwords
|
|
.loop:
|
|
rcl dword[edi], 1
|
|
lea edi, [edi+4]
|
|
dec ecx
|
|
jnz .loop
|
|
.done:
|
|
jc .carry
|
|
test dword[edi-4], 0x10000000
|
|
jnz .add0
|
|
ret
|
|
|
|
.carry:
|
|
mov ecx, [dst]
|
|
cmp dword[ecx], MPINT_MAX_LEN
|
|
je .ovf
|
|
add dword[ecx], 4
|
|
mov dword[edi], 1
|
|
ret
|
|
|
|
.add0:
|
|
mov ecx, [dst]
|
|
cmp dword[ecx], MPINT_MAX_LEN
|
|
je .ovf
|
|
add dword[ecx], 4
|
|
mov dword[edi], 0
|
|
ret
|
|
|
|
.ovf:
|
|
int3
|
|
;;;;
|
|
ret
|
|
|
|
.adjust_needed:
|
|
add ecx, 3
|
|
and ecx, not 3
|
|
stdcall mpint_grow, edi, ecx
|
|
jmp .length_ok
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_shr1 uses edi ecx, dst ;//////////////////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Shift little endian MPINT one bit to the right. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = dst SHR 1 ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_shr1(0x%x)\n", [dst]
|
|
|
|
mov edi, [dst]
|
|
mov ecx, [edi]
|
|
test ecx, 11b
|
|
jnz .adjust_needed
|
|
|
|
.length_ok:
|
|
shr ecx, 2
|
|
jz .done
|
|
lea edi, [edi+ecx*4]
|
|
; Do the highest order dword first
|
|
shr dword[edi], 1
|
|
lea edi, [edi-4]
|
|
dec ecx
|
|
jz .done
|
|
; And the remaining dwords
|
|
.loop:
|
|
rcr dword[edi], 1
|
|
lea edi, [edi-4]
|
|
dec ecx
|
|
jnz .loop
|
|
.done:
|
|
ret
|
|
|
|
.adjust_needed:
|
|
add ecx, 3
|
|
and ecx, not 3
|
|
stdcall mpint_grow, edi, ecx
|
|
jmp .length_ok
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_shl uses eax ebx ecx edx esi edi, dst, shift ;////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Left shift little endian MPINT by x bits. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;> shift = number of bits to shift the MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< - ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_shl(0x%x, %u)\n", [dst], [shift]
|
|
|
|
; Calculate new size
|
|
stdcall mpint_bits, [dst]
|
|
add eax, [shift]
|
|
shr eax, 3
|
|
cmp eax, MPINT_MAX_LEN
|
|
jae .overflow ;;
|
|
inc eax
|
|
mov esi, [dst]
|
|
mov [esi], eax
|
|
|
|
mov ecx, [shift]
|
|
shr ecx, 3 ; 8 bits in one byte
|
|
add esi, MPINT_MAX_LEN+4-4
|
|
mov edi, esi
|
|
and ecx, not 11b
|
|
sub esi, ecx
|
|
mov edx, MPINT_MAX_LEN/4-1
|
|
shr ecx, 2 ; 4 bytes in one dword
|
|
push ecx
|
|
sub edx, ecx
|
|
mov ecx, [shift]
|
|
and ecx, 11111b
|
|
std
|
|
.loop:
|
|
lodsd
|
|
mov ebx, [esi]
|
|
shld eax, ebx, cl
|
|
stosd
|
|
dec edx
|
|
jnz .loop
|
|
lodsd
|
|
shl eax, cl
|
|
stosd
|
|
|
|
; fill the LSBs with zeros
|
|
pop ecx
|
|
test ecx, ecx
|
|
jz @f
|
|
xor eax, eax
|
|
rep stosd
|
|
@@:
|
|
cld
|
|
ret
|
|
|
|
.zero:
|
|
mov eax, [dst]
|
|
mov dword[eax], 0
|
|
ret
|
|
|
|
.overflow:
|
|
int3
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_shlmov uses eax ebx ecx edx esi edi, dst, src, shift ;////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Left shift by x bits and copy little endian MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;> shift = number of bits to shift the MPINT to the left ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = src SHL shift ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_shlmov(0x%x, 0x%x, %u)\n", [dst], [src], [shift]
|
|
|
|
stdcall mpint_bits, [src]
|
|
test eax, eax
|
|
jz .zero
|
|
add eax, [shift]
|
|
shr eax, 3
|
|
inc eax
|
|
mov edi, [dst]
|
|
mov [edi], eax
|
|
|
|
cmp eax, MPINT_MAX_LEN
|
|
jae .overflow
|
|
|
|
mov esi, [src]
|
|
add esi, MPINT_MAX_LEN+4-4
|
|
add edi, MPINT_MAX_LEN+4-4
|
|
mov ecx, [shift]
|
|
shr ecx, 3 ; 8 bits in one byte
|
|
and ecx, not 11b
|
|
sub esi, ecx
|
|
mov edx, MPINT_MAX_LEN/4-1
|
|
shr ecx, 2 ; 4 bytes in one dword
|
|
push ecx
|
|
sub edx, ecx
|
|
mov ecx, [shift]
|
|
and ecx, 11111b
|
|
std
|
|
.loop:
|
|
lodsd
|
|
mov ebx, [esi]
|
|
shld eax, ebx, cl
|
|
stosd
|
|
dec edx
|
|
jnz .loop
|
|
lodsd
|
|
shl eax, cl
|
|
stosd
|
|
|
|
; fill the lsb bytes with zeros
|
|
pop ecx
|
|
test ecx, ecx
|
|
jz @f
|
|
xor eax, eax
|
|
rep stosd
|
|
@@:
|
|
cld
|
|
ret
|
|
|
|
.zero:
|
|
mov eax, [dst]
|
|
mov dword[eax], 0
|
|
ret
|
|
|
|
.overflow:
|
|
int3
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_add uses esi edi edx ecx ebx eax, dst, src ;//////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Add a little endian MPINT to another little endian MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = dst + src ;;
|
|
;;===========================================================================;;
|
|
|
|
locals
|
|
dd_cnt dd ?
|
|
endl
|
|
|
|
DEBUGF 1, "mpint_add(0x%x, 0x%x)\n", [dst], [src]
|
|
|
|
; Grow both numbers to same 4-byte boundary, if not already the case
|
|
mov esi, [src]
|
|
mov edi, [dst]
|
|
mov ecx, [esi]
|
|
test ecx, 11b
|
|
jnz .adjust_needed
|
|
cmp ecx, [edi]
|
|
jne .adjust_needed
|
|
|
|
; Do the additions
|
|
.length_ok:
|
|
add esi, 4
|
|
add edi, 4
|
|
shr ecx, 2
|
|
jz .done
|
|
mov eax, ecx
|
|
and eax, 111b
|
|
mov [dd_cnt], eax
|
|
shr ecx, 3
|
|
test ecx, ecx ; Clear carry flag
|
|
jz .no32
|
|
|
|
.loop32:
|
|
mov eax, [esi+00]
|
|
mov edx, [esi+04]
|
|
adc [edi+00], eax
|
|
adc [edi+04], edx
|
|
|
|
mov eax, [esi+08]
|
|
mov edx, [esi+12]
|
|
adc [edi+08], eax
|
|
adc [edi+12], edx
|
|
|
|
mov eax, [esi+16]
|
|
mov edx, [esi+20]
|
|
adc [edi+16], eax
|
|
adc [edi+20], edx
|
|
|
|
mov eax, [esi+24]
|
|
mov edx, [esi+28]
|
|
adc [edi+24], eax
|
|
adc [edi+28], edx
|
|
|
|
lea esi, [esi + 32]
|
|
lea edi, [edi + 32]
|
|
dec ecx
|
|
jnz .loop32
|
|
|
|
.no32:
|
|
mov ecx, [dd_cnt]
|
|
dec ecx
|
|
js .check_ovf
|
|
inc ecx
|
|
.dword_loop:
|
|
mov eax, [esi+0]
|
|
adc [edi+0], eax
|
|
lea esi, [esi + 4]
|
|
lea edi, [edi + 4]
|
|
dec ecx
|
|
jnz .dword_loop
|
|
|
|
.check_ovf:
|
|
jc .add_1 ; Carry
|
|
test byte[edi-1], 0x80
|
|
jnz .add_0 ; Currently highest bit set
|
|
.done:
|
|
ret
|
|
|
|
; Highest bit was set, add a 0 byte as MSB if possible
|
|
.add_0:
|
|
mov ecx, [dst]
|
|
cmp dword[ecx], MPINT_MAX_LEN
|
|
jae .ovf_0
|
|
mov byte[edi], 0
|
|
inc dword[ecx]
|
|
ret
|
|
|
|
.ovf_0:
|
|
int3
|
|
clc
|
|
; TODO: set overflow flag?
|
|
ret
|
|
|
|
; Carry bit was set, add a 1 byte as MSB if possible
|
|
.add_1:
|
|
mov ecx, [dst]
|
|
cmp dword[ecx], MPINT_MAX_LEN
|
|
jae .ovf_1
|
|
mov byte[edi], 1
|
|
inc dword[ecx]
|
|
ret
|
|
|
|
.ovf_1:
|
|
int3
|
|
stc
|
|
; TODO: set overflow flag?
|
|
ret
|
|
|
|
.adjust_needed:
|
|
; mov ecx, [esi]
|
|
mov eax, [edi]
|
|
; find the maximum of the two in ecx
|
|
mov edx, ecx
|
|
sub edx, eax
|
|
sbb ebx, ebx
|
|
and ebx, edx
|
|
sub ecx, ebx
|
|
; align to 4 byte boundary
|
|
add ecx, 3
|
|
and ecx, not 3
|
|
; adjust both mpints
|
|
stdcall mpint_grow, esi, ecx
|
|
stdcall mpint_grow, edi, ecx
|
|
jmp .length_ok
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_sub uses esi edi edx ecx ebx eax, dst, src ;//////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Subtract a little endian MPINT to another little endian MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = dst - src ;;
|
|
;;===========================================================================;;
|
|
|
|
locals
|
|
dd_cnt dd ?
|
|
endl
|
|
|
|
DEBUGF 1, "mpint_sub(0x%x, 0x%x)\n", [dst], [src]
|
|
|
|
; Grow both numbers to same 4-byte boundary, if not already the case
|
|
mov esi, [src]
|
|
mov edi, [dst]
|
|
mov ecx, [esi]
|
|
test ecx, 11b
|
|
jnz .adjust_needed
|
|
cmp ecx, [edi]
|
|
jne .adjust_needed
|
|
|
|
; Do the subtractions
|
|
.length_ok:
|
|
add esi, 4
|
|
add edi, 4
|
|
shr ecx, 2
|
|
jz .done
|
|
mov eax, ecx
|
|
and eax, 111b
|
|
mov [dd_cnt], eax
|
|
shr ecx, 3
|
|
test ecx, ecx ; Clear carry flag
|
|
jz .no32
|
|
|
|
.loop32:
|
|
mov eax, [esi+00]
|
|
mov edx, [esi+04]
|
|
sbb [edi+00], eax
|
|
sbb [edi+04], edx
|
|
|
|
mov eax, [esi+08]
|
|
mov edx, [esi+12]
|
|
sbb [edi+08], eax
|
|
sbb [edi+12], edx
|
|
|
|
mov eax, [esi+16]
|
|
mov edx, [esi+20]
|
|
sbb [edi+16], eax
|
|
sbb [edi+20], edx
|
|
|
|
mov eax, [esi+24]
|
|
mov edx, [esi+28]
|
|
sbb [edi+24], eax
|
|
sbb [edi+28], edx
|
|
|
|
lea esi, [esi + 32]
|
|
lea edi, [edi + 32]
|
|
dec ecx
|
|
jnz .loop32
|
|
|
|
.no32:
|
|
mov ecx, [dd_cnt]
|
|
dec ecx
|
|
js .done
|
|
inc ecx
|
|
.dword_loop:
|
|
mov eax, [esi+0]
|
|
sbb [edi+0], eax
|
|
lea esi, [esi + 4]
|
|
lea edi, [edi + 4]
|
|
dec ecx
|
|
jnz .dword_loop
|
|
|
|
.done:
|
|
ret
|
|
|
|
.adjust_needed:
|
|
; mov ecx, [esi]
|
|
mov eax, [edi]
|
|
; find the maximum of the two in ecx
|
|
mov edx, ecx
|
|
sub edx, eax
|
|
sbb ebx, ebx
|
|
and ebx, edx
|
|
sub ecx, ebx
|
|
; align to 4 byte boundary
|
|
add ecx, 3
|
|
and ecx, not 3
|
|
; adjust both mpints
|
|
stdcall mpint_grow, esi, ecx
|
|
stdcall mpint_grow, edi, ecx
|
|
jmp .length_ok
|
|
|
|
endp
|
|
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_shrink uses eax edi, dst ;////////////////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Get rid of unnescessary leading zeroes on a little endian MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_shrink(0x%x)\n", [dst]
|
|
|
|
stdcall mpint_bits, [dst]
|
|
shr eax, 3
|
|
inc eax
|
|
mov edi, [dst]
|
|
mov [edi], eax
|
|
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_grow uses eax edi ecx, dst, length ;//////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Add leading zeroes on a little endian MPINT. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> src = pointer to little endian MPINT ;;
|
|
;> length = total length of the new MPINT in bytes ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< ;;
|
|
;;===========================================================================;;
|
|
|
|
DEBUGF 1, "mpint_grow(0x%x, %u): ", [dst], [length]
|
|
|
|
mov edi, [dst]
|
|
mov eax, [edi]
|
|
mov ecx, [length]
|
|
sub ecx, eax
|
|
jbe .dontgrow
|
|
lea edi, [edi + 4 + eax]
|
|
xor al, al
|
|
rep stosb
|
|
mov eax, [length]
|
|
mov edi, [dst]
|
|
mov [edi], eax
|
|
DEBUGF 1, "ok\n"
|
|
ret
|
|
|
|
.dontgrow:
|
|
DEBUGF 1, "already large enough!\n"
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_mul uses eax ebx ecx edx esi edi, dst, a, b ;/////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Multiply a little endian MPINT with another little endian MPINT and store ;;
|
|
;? in a third one. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;> a = pointer to little endian MPINT ;;
|
|
;> b = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = a * b ;;
|
|
;;===========================================================================;;
|
|
|
|
locals
|
|
asize dd ?
|
|
bsize dd ?
|
|
counter dd ?
|
|
esp_ dd ?
|
|
endl
|
|
|
|
DEBUGF 1, "mpint_mul(0x%x, 0x%x, 0x%x)\n", [dst], [a], [b]
|
|
|
|
; Grow both numbers to individual 4-byte boundary, if not already the case
|
|
mov esi, [a]
|
|
mov edx, [b]
|
|
mov ecx, [esi]
|
|
mov ebx, [edx]
|
|
test ecx, 11b
|
|
jnz .adjust_needed
|
|
test ebx, 11b
|
|
jnz .adjust_needed
|
|
.length_ok:
|
|
|
|
; Must have a size >= b size.
|
|
cmp ebx, ecx
|
|
ja .swap_a_b
|
|
.conditions_ok:
|
|
|
|
; dst size will be a size + b size
|
|
lea eax, [ebx + ecx]
|
|
cmp eax, MPINT_MAX_LEN
|
|
ja .ovf
|
|
|
|
; [asize] = number of dwords in a
|
|
shr ecx, 2
|
|
jz .zero
|
|
mov [asize], ecx
|
|
; esi = x ptr
|
|
add esi, 4
|
|
|
|
; [bsize] = number of dwords in b
|
|
shr ebx, 2
|
|
jz .zero
|
|
mov [bsize], ebx
|
|
; edx = b ptr (temporarily)
|
|
add edx, 4
|
|
|
|
; store dst size
|
|
mov edi, [dst]
|
|
mov [edi], eax
|
|
; edi = dst ptr
|
|
add edi, 4
|
|
|
|
; Use esp as frame pointer instead of ebp
|
|
; ! Use the stack with extreme caution from here on !
|
|
mov [esp_], esp
|
|
mov esp, ebp
|
|
|
|
; ebp = b ptr
|
|
mov ebp, edx
|
|
|
|
; Do the first multiplication
|
|
mov eax, [esi] ; load a[0]
|
|
mul dword[ebp] ; multiply by b[0]
|
|
mov [edi], eax ; store to dest[0]
|
|
; mov ecx, [asize] ; asize
|
|
dec ecx ; if asize = 1, bsize = 1 too
|
|
jz .done
|
|
|
|
; Prepare to enter loop1
|
|
mov eax, [asize-ebp+esp]
|
|
|
|
mov ebx, edx
|
|
lea esi, [esi + eax * 4] ; make a ptr point at end
|
|
lea edi, [edi + eax * 4] ; offset dst ptr by asize
|
|
neg ecx ; negate j size/index for inner loop
|
|
xor eax, eax ; clear carry
|
|
|
|
align 8
|
|
.loop1:
|
|
adc ebx, 0
|
|
mov eax, [esi + ecx * 4] ; load next dword at a[j]
|
|
mul dword[ebp]
|
|
add eax, ebx
|
|
mov [edi + ecx * 4], eax
|
|
inc ecx
|
|
mov ebx, edx
|
|
jnz .loop1
|
|
|
|
adc ebx, 0
|
|
mov eax, [bsize-ebp+esp]
|
|
mov [edi], ebx ; most significant dword of the product
|
|
add edi, 4 ; increment dst
|
|
dec eax
|
|
jz .skip
|
|
mov [counter-ebp+esp], eax ; set index i to bsize
|
|
|
|
.outer:
|
|
add ebp, 4 ; make ebp point to next b dword
|
|
mov ecx, [asize-ebp+esp]
|
|
neg ecx
|
|
xor ebx, ebx
|
|
|
|
.loop2:
|
|
adc ebx, 0
|
|
mov eax, [esi + ecx * 4]
|
|
mul dword[ebp]
|
|
add eax, ebx
|
|
mov ebx, [edi + ecx * 4]
|
|
adc edx, 0
|
|
add ebx, eax
|
|
mov [edi + ecx * 4], ebx
|
|
inc ecx
|
|
mov ebx, edx
|
|
jnz .loop2
|
|
|
|
adc ebx, 0
|
|
|
|
mov [edi], ebx
|
|
add edi, 4
|
|
mov eax, [counter-ebp+esp]
|
|
dec eax
|
|
mov [counter-ebp+esp], eax
|
|
jnz .outer
|
|
|
|
.skip:
|
|
; restore esp, ebp
|
|
mov ebp, esp
|
|
mov esp, [esp_]
|
|
|
|
ret
|
|
|
|
.done:
|
|
mov [edi+4], edx ; store to dst[1]
|
|
; restore esp, ebp
|
|
mov ebp, esp
|
|
mov esp, [esp_]
|
|
|
|
ret
|
|
|
|
.ovf:
|
|
int3
|
|
|
|
.zero:
|
|
mov eax, [dst]
|
|
mov dword[eax], 0
|
|
|
|
ret
|
|
|
|
.adjust_needed:
|
|
; align to 4 byte boundary
|
|
add ecx, 3
|
|
and ecx, not 3
|
|
add ebx, 3
|
|
and ebx, not 3
|
|
; adjust both mpints
|
|
stdcall mpint_grow, esi, ecx
|
|
stdcall mpint_grow, edx, ebx
|
|
jmp .length_ok
|
|
|
|
.swap_a_b:
|
|
mov eax, esi
|
|
mov esi, edx
|
|
mov edx, eax
|
|
|
|
mov eax, ebx
|
|
mov ebx, ecx
|
|
mov ecx, eax
|
|
jmp .conditions_ok
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_mod uses eax ebx ecx, dst, m ;////////////////////////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Find the modulo (remainder after division) of dst by mod. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to little endian MPINT ;;
|
|
;> mod = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = dst MOD m ;;
|
|
;;===========================================================================;;
|
|
|
|
locals
|
|
mpint_tmp rb MPINT_MAX_LEN+4
|
|
endl
|
|
|
|
DEBUGF 1, "mpint_mod(0x%x, 0x%x)\n", [dst], [m]
|
|
|
|
stdcall mpint_cmp, [m], [dst]
|
|
ja .done ; if mod > dst, dst = dst
|
|
je .zero ; if mod == dst, dst = 0
|
|
|
|
; left shift mod until the high order bits of mod and dst are aligned
|
|
|
|
stdcall mpint_bits, [dst]
|
|
mov ecx, eax
|
|
stdcall mpint_bits, [m]
|
|
test eax, eax
|
|
jz .zero ; if mod is zero, return
|
|
sub ecx, eax
|
|
lea ebx, [mpint_tmp]
|
|
stdcall mpint_shlmov, ebx, [m], ecx
|
|
inc ecx
|
|
|
|
; For every bit in dst (starting from the high order bit):
|
|
.bitloop:
|
|
stdcall mpint_cmp, [dst], ebx ; If dst > mpint_tmp
|
|
jb @f
|
|
stdcall mpint_sub, [dst], ebx ; dst = dst - mpint_tmp
|
|
@@:
|
|
dec ecx
|
|
jz .done
|
|
|
|
stdcall mpint_shr1, ebx ; mpint = mpint >> 1
|
|
jmp .bitloop
|
|
|
|
.done:
|
|
; adjust size of dst so it is no larger than mod
|
|
mov ebx, [dst]
|
|
mov ecx, [ebx] ; current size
|
|
mov eax, [m]
|
|
mov eax, [eax] ; size of mod
|
|
cmp ecx, eax
|
|
jb .ret
|
|
mov [ebx], eax
|
|
.ret:
|
|
ret
|
|
|
|
.zero:
|
|
mov ebx, [dst]
|
|
mov dword[ebx], 0
|
|
ret
|
|
|
|
endp
|
|
|
|
;;===========================================================================;;
|
|
proc mpint_modexp uses edi eax ebx ecx edx, dest, b, e, m ;//////////////////;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;? Find the modulo (remainder after division) of dst by mod. ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;> dst = pointer to buffer for little endian MPINT ;;
|
|
;> base = pointer to little endian MPINT ;;
|
|
;> exp = pointer to little endian MPINT ;;
|
|
;> mod = pointer to little endian MPINT ;;
|
|
;;---------------------------------------------------------------------------;;
|
|
;< dst = b ** e MOD m ;;
|
|
;;===========================================================================;;
|
|
|
|
locals
|
|
dst1 dd ?
|
|
dst2 dd ?
|
|
tmp rb MPINT_MAX_LEN+4
|
|
endl
|
|
|
|
DEBUGF 1, "mpint_modexp(0x%x, 0x%x, 0x%x, 0x%x)\n", [dest], [b], [e], [m]
|
|
|
|
; If mod is zero, return
|
|
stdcall mpint_bytes, [m]
|
|
test eax, eax
|
|
jz .mod_zero
|
|
test eax, 3
|
|
jnz .grow_mod
|
|
.modsize_ok:
|
|
|
|
; Find highest order byte in exponent
|
|
stdcall mpint_bytes, [e]
|
|
test eax, eax
|
|
jz .exp_zero
|
|
mov ecx, eax
|
|
mov edi, [e]
|
|
lea edi, [edi + 4 + ecx - 1]
|
|
|
|
; Set up temp variables
|
|
lea eax, [tmp]
|
|
mov edx, [dest]
|
|
mov [dst1], eax
|
|
mov [dst2], edx
|
|
|
|
; Find the highest order bit in this byte
|
|
mov al, [edi]
|
|
test al, al
|
|
jz .invalid
|
|
mov bl, 9
|
|
@@:
|
|
dec bl
|
|
shl al, 1
|
|
jnc @r
|
|
|
|
; Initialise result to base, to take care of the highest order bit
|
|
stdcall mpint_mov, [dst1], [b]
|
|
dec bl
|
|
jz .next_byte
|
|
.bit_loop:
|
|
; For each bit, square result
|
|
stdcall mpint_mul, [dst2], [dst1], [dst1]
|
|
stdcall mpint_mod, [dst2], [m]
|
|
|
|
; If the bit is set, multiply result by the base
|
|
shl al, 1
|
|
jnc .bit_zero
|
|
stdcall mpint_mul, [dst1], [b], [dst2]
|
|
stdcall mpint_mod, [dst1], [m]
|
|
dec bl
|
|
jnz .bit_loop
|
|
jmp .next_byte
|
|
|
|
.bit_zero:
|
|
mov edx, [dst1]
|
|
mov esi, [dst2]
|
|
mov [dst2], edx
|
|
mov [dst1], esi
|
|
dec bl
|
|
jnz .bit_loop
|
|
|
|
.next_byte:
|
|
dec ecx
|
|
jz .done
|
|
dec edi
|
|
mov al, [edi]
|
|
mov bl, 8
|
|
jmp .bit_loop
|
|
.done:
|
|
mov edx, [dest]
|
|
cmp edx, [dst1]
|
|
je @f
|
|
stdcall mpint_mov, [dest], [dst1]
|
|
@@:
|
|
|
|
ret
|
|
|
|
.mod_zero:
|
|
DEBUGF 3, "modexp with modulo 0\n"
|
|
; if mod is zero, result = 0
|
|
mov eax, [dest]
|
|
mov dword[eax], 0
|
|
ret
|
|
|
|
.exp_zero:
|
|
DEBUGF 3, "modexp with exponent 0\n"
|
|
; if exponent is zero, result = 1
|
|
mov eax, [dest]
|
|
mov dword[eax], 1
|
|
mov byte[eax+4], 1
|
|
ret
|
|
|
|
.invalid:
|
|
DEBUGF 3, "modexp: Invalid input!\n"
|
|
ret
|
|
|
|
.grow_mod:
|
|
add eax, 3
|
|
and eax, not 3
|
|
stdcall mpint_grow, [m], eax
|
|
jmp .modsize_ok
|
|
|
|
endp
|
|
|
|
|