Commit 8f2d60ec authored by Andy Polyakov's avatar Andy Polyakov
Browse files

Fix for "strange errors" exposed by ccgost engine. The fix is 

two extra insructions in sqradd loop at line #503.
parent 123b23fa

crypto/bn/asm/x86-mont.pl

+10 −10
Original line number Diff line number Diff line
@@ -360,7 +360,7 @@ $carry="ebp"; 


	&mov	($carry,"edx");

	&mul	($word);				# np[j]*m

	&add	($carry,&DWP($frame,"esp",$j,4));	# +=tp[j]

	&add	($carry,&DWP($frame,"esp",$num,4));	# +=tp[num-1]

	&adc	("edx",0);

	&add	($carry,"eax");

	&adc	("edx",0);
@@ -374,9 +374,9 @@ $carry="ebp"; 
	&mov	(&DWP($frame,"esp",$num,4),"edx");	# tp[num-1]=

	 &cmp	($j,$_bpend);

	&mov	(&DWP($frame+4,"esp",$num,4),"eax");	# tp[num]=

	&je	(&label("x86done"));

	&je	(&label("common_tail"));



	&mov	($word,&DWP(0,$j));			# bp[i]

	&mov	($word,&DWP(0,$j));			# bp[i+1]

	&mov	($inp,$_ap);

	&mov	($_bp,$j);				# &bp[++i]

	&xor	($j,$j);
@@ -473,7 +473,7 @@ $sbit=$num; 
	&mov	(&DWP($frame,"esp",$num,4),"edx");	# tp[num-1]=

	&cmp	($j,$num);

	&mov	(&DWP($frame+4,"esp",$num,4),"eax");	# tp[num]=

	&je	(&label("x86done"));

	&je	(&label("common_tail"));



	&mov	($word,&DWP(4,$inp,$j,4));		# ap[i]

	&lea	($j,&DWP(1,$j));
@@ -500,6 +500,8 @@ $sbit=$num; 
	&adc	("edx",0);

	&lea	($carry,&DWP(0,$sbit,"eax",2));

	&shr	("eax",31);

	&cmp	($carry,$sbit);

	&adc	("eax",0);

	&add	($carry,&DWP($frame-4,"esp",$j,4));	# +=tp[j]

	&adc	("eax",0);

	&cmp	($j,$_num);
@@ -529,12 +531,10 @@ $sbit=$num; 
	&mov	("eax",&DWP(4,$inp));			# np[1]



	&jmp	(&label("3rdmadd"));



&set_label("x86done",4);

	&mov	($np,$_np);	# make adjustments for tail processing

}





&set_label("common_tail",16);

	&mov	($np,$_np);

	&mov	("esi",&DWP($frame+4,"esp",$num,4));# load upmost overflow bit

	&mov	($rp,$_rp);			# load result pointer

						# [$ap and $bp are zapped]
@@ -563,12 +563,12 @@ $sbit=$num; 
	&mov	($j,$num);			# j=num-1

	&sbb	("esi",0);			# esi holds upmost overflow bit

	&jc	(&label("copy"));

&set_label("zap",16);

&set_label("zap",8);

	&mov	(&DWP($frame,"esp",$j,4),$i);	# zap temporary vector

	&dec	($j);

	&jge	(&label("zap"));



&set_label("exit",4);

&set_label("exit",8);

	&mov	("esp",$_sp);		# pull saved stack pointer

	&mov	("eax",1);

&set_label("just_leave");