Import OpenSSL 1.0.2i.vendor/openssl/1.0.2i

11 files changed, 341 insertions, 210 deletions

diff --git a/crypto/bn/asm/x86-mont.pl b/crypto/bn/asm/x86-mont.pl
index 89f4de61e896..1c4003efc20a 100755
--- a/crypto/bn/asm/x86-mont.pl
+++ b/crypto/bn/asm/x86-mont.pl
@@ -63,27 +63,26 @@ $frame=32;				# size of above frame rounded up to 16n
 
 	&lea	("esi",&wparam(0));	# put aside pointer to argument block
 	&lea	("edx",&wparam(1));	# load ap
-	&mov	("ebp","esp");		# saved stack pointer!
 	&add	("edi",2);		# extra two words on top of tp
 	&neg	("edi");
-	&lea	("esp",&DWP(-$frame,"esp","edi",4));	# alloca($frame+4*(num+2))
+	&lea	("ebp",&DWP(-$frame,"esp","edi",4));	# future alloca($frame+4*(num+2))
 	&neg	("edi");
 
 	# minimize cache contention by arraning 2K window between stack
 	# pointer and ap argument [np is also position sensitive vector,
 	# but it's assumed to be near ap, as it's allocated at ~same
 	# time].
-	&mov	("eax","esp");
+	&mov	("eax","ebp");
 	&sub	("eax","edx");
 	&and	("eax",2047);
-	&sub	("esp","eax");		# this aligns sp and ap modulo 2048
+	&sub	("ebp","eax");		# this aligns sp and ap modulo 2048
 
-	&xor	("edx","esp");
+	&xor	("edx","ebp");
 	&and	("edx",2048);
 	&xor	("edx",2048);
-	&sub	("esp","edx");		# this splits them apart modulo 4096
+	&sub	("ebp","edx");		# this splits them apart modulo 4096
 
-	&and	("esp",-64);		# align to cache line
+	&and	("ebp",-64);		# align to cache line
 
 	# Some OSes, *cough*-dows, insist on stack being "wired" to
 	# physical memory in strictly sequential manner, i.e. if stack
@@ -91,20 +90,28 @@ $frame=32;				# size of above frame rounded up to 16n
 	# be punishable by SEGV. But page walking can do good even on
 	# other OSes, because it guarantees that villain thread hits
 	# the guard page before it can make damage to innocent one...
-	&mov	("eax","ebp");
-	&sub	("eax","esp");
+	&mov	("eax","esp");
+	&sub	("eax","ebp");
 	&and	("eax",-4096);
-&set_label("page_walk");
-	&mov	("edx",&DWP(0,"esp","eax"));
-	&sub	("eax",4096);
-	&data_byte(0x2e);
-	&jnc	(&label("page_walk"));
+	&mov	("edx","esp");		# saved stack pointer!
+	&lea	("esp",&DWP(0,"ebp","eax"));
+	&mov	("eax",&DWP(0,"esp"));
+	&cmp	("esp","ebp");
+	&ja	(&label("page_walk"));
+	&jmp	(&label("page_walk_done"));
+
+&set_label("page_walk",16);
+	&lea	("esp",&DWP(-4096,"esp"));
+	&mov	("eax",&DWP(0,"esp"));
+	&cmp	("esp","ebp");
+	&ja	(&label("page_walk"));
+&set_label("page_walk_done");
 
 	################################# load argument block...
 	&mov	("eax",&DWP(0*4,"esi"));# BN_ULONG *rp
 	&mov	("ebx",&DWP(1*4,"esi"));# const BN_ULONG *ap
 	&mov	("ecx",&DWP(2*4,"esi"));# const BN_ULONG *bp
-	&mov	("edx",&DWP(3*4,"esi"));# const BN_ULONG *np
+	&mov	("ebp",&DWP(3*4,"esi"));# const BN_ULONG *np
 	&mov	("esi",&DWP(4*4,"esi"));# const BN_ULONG *n0
 	#&mov	("edi",&DWP(5*4,"esi"));# int num
 
@@ -112,11 +119,11 @@ $frame=32;				# size of above frame rounded up to 16n
 	&mov	($_rp,"eax");		# ... save a copy of argument block
 	&mov	($_ap,"ebx");
 	&mov	($_bp,"ecx");
-	&mov	($_np,"edx");
+	&mov	($_np,"ebp");
 	&mov	($_n0,"esi");
 	&lea	($num,&DWP(-3,"edi"));	# num=num-1 to assist modulo-scheduling
 	#&mov	($_num,$num);		# redundant as $num is not reused
-	&mov	($_sp,"ebp");		# saved stack pointer!
+	&mov	($_sp,"edx");		# saved stack pointer!
 
 if($sse2) {
 $acc0="mm0";	# mmx register bank layout
diff --git a/crypto/bn/asm/x86_64-gcc.c b/crypto/bn/asm/x86_64-gcc.c
index d77dc433d405..1729b479d43e 100644
--- a/crypto/bn/asm/x86_64-gcc.c
+++ b/crypto/bn/asm/x86_64-gcc.c
@@ -194,7 +194,7 @@ BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d)
     BN_ULONG ret, waste;
 
  asm("divq      %4":"=a"(ret), "=d"(waste)
- :     "a"(l), "d"(h), "g"(d)
+ :     "a"(l), "d"(h), "r"(d)
  :     "cc");
 
     return ret;
diff --git a/crypto/bn/asm/x86_64-mont.pl b/crypto/bn/asm/x86_64-mont.pl
index 8fb6c994e1ef..044fd7ecc0fd 100755
--- a/crypto/bn/asm/x86_64-mont.pl
+++ b/crypto/bn/asm/x86_64-mont.pl
@@ -97,6 +97,8 @@ $code=<<___;
 .type	bn_mul_mont,\@function,6
 .align	16
 bn_mul_mont:
+	mov	${num}d,${num}d
+	mov	%rsp,%rax
 	test	\$3,${num}d
 	jnz	.Lmul_enter
 	cmp	\$8,${num}d
@@ -121,29 +123,36 @@ $code.=<<___;
 	push	%r14
 	push	%r15
 
-	mov	${num}d,${num}d
-	lea	2($num),%r10
+	neg	$num
 	mov	%rsp,%r11
-	neg	%r10
-	lea	(%rsp,%r10,8),%rsp	# tp=alloca(8*(num+2))
-	and	\$-1024,%rsp		# minimize TLB usage
+	lea	-16(%rsp,$num,8),%r10	# future alloca(8*(num+2))
+	neg	$num			# restore $num
+	and	\$-1024,%r10		# minimize TLB usage
 
-	mov	%r11,8(%rsp,$num,8)	# tp[num+1]=%rsp
-.Lmul_body:
 	# Some OSes, *cough*-dows, insist on stack being "wired" to
 	# physical memory in strictly sequential manner, i.e. if stack
 	# allocation spans two pages, then reference to farmost one can
 	# be punishable by SEGV. But page walking can do good even on
 	# other OSes, because it guarantees that villain thread hits
 	# the guard page before it can make damage to innocent one...
-	sub	%rsp,%r11
+	sub	%r10,%r11
 	and	\$-4096,%r11
+	lea	(%r10,%r11),%rsp
+	mov	(%rsp),%r11
+	cmp	%r10,%rsp
+	ja	.Lmul_page_walk
+	jmp	.Lmul_page_walk_done
+
+.align	16
 .Lmul_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x66,0x2e		# predict non-taken
-	jnc	.Lmul_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r11
+	cmp	%r10,%rsp
+	ja	.Lmul_page_walk
+.Lmul_page_walk_done:
 
+	mov	%rax,8(%rsp,$num,8)	# tp[num+1]=%rsp
+.Lmul_body:
 	mov	$bp,%r12		# reassign $bp
 ___
 		$bp="%r12";
@@ -314,13 +323,13 @@ $code.=<<___;
 
 	mov	8(%rsp,$num,8),%rsi	# restore %rsp
 	mov	\$1,%rax
-	mov	(%rsi),%r15
-	mov	8(%rsi),%r14
-	mov	16(%rsi),%r13
-	mov	24(%rsi),%r12
-	mov	32(%rsi),%rbp
-	mov	40(%rsi),%rbx
-	lea	48(%rsi),%rsp
+	mov	-48(%rsi),%r15
+	mov	-40(%rsi),%r14
+	mov	-32(%rsi),%r13
+	mov	-24(%rsi),%r12
+	mov	-16(%rsi),%rbp
+	mov	-8(%rsi),%rbx
+	lea	(%rsi),%rsp
 .Lmul_epilogue:
 	ret
 .size	bn_mul_mont,.-bn_mul_mont
@@ -332,6 +341,8 @@ $code.=<<___;
 .type	bn_mul4x_mont,\@function,6
 .align	16
 bn_mul4x_mont:
+	mov	${num}d,${num}d
+	mov	%rsp,%rax
 .Lmul4x_enter:
 ___
 $code.=<<___ if ($addx);
@@ -347,23 +358,29 @@ $code.=<<___;
 	push	%r14
 	push	%r15
 
-	mov	${num}d,${num}d
-	lea	4($num),%r10
+	neg	$num
 	mov	%rsp,%r11
-	neg	%r10
-	lea	(%rsp,%r10,8),%rsp	# tp=alloca(8*(num+4))
-	and	\$-1024,%rsp		# minimize TLB usage
+	lea	-32(%rsp,$num,8),%r10	# future alloca(8*(num+4))
+	neg	$num			# restore
+	and	\$-1024,%r10		# minimize TLB usage
 
-	mov	%r11,8(%rsp,$num,8)	# tp[num+1]=%rsp
-.Lmul4x_body:
-	sub	%rsp,%r11
+	sub	%r10,%r11
 	and	\$-4096,%r11
+	lea	(%r10,%r11),%rsp
+	mov	(%rsp),%r11
+	cmp	%r10,%rsp
+	ja	.Lmul4x_page_walk
+	jmp	.Lmul4x_page_walk_done
+
 .Lmul4x_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x2e			# predict non-taken
-	jnc	.Lmul4x_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r11
+	cmp	%r10,%rsp
+	ja	.Lmul4x_page_walk
+.Lmul4x_page_walk_done:
 
+	mov	%rax,8(%rsp,$num,8)	# tp[num+1]=%rsp
+.Lmul4x_body:
 	mov	$rp,16(%rsp,$num,8)	# tp[num+2]=$rp
 	mov	%rdx,%r12		# reassign $bp
 ___
@@ -742,13 +759,13 @@ ___
 $code.=<<___;
 	mov	8(%rsp,$num,8),%rsi	# restore %rsp
 	mov	\$1,%rax
-	mov	(%rsi),%r15
-	mov	8(%rsi),%r14
-	mov	16(%rsi),%r13
-	mov	24(%rsi),%r12
-	mov	32(%rsi),%rbp
-	mov	40(%rsi),%rbx
-	lea	48(%rsi),%rsp
+	mov	-48(%rsi),%r15
+	mov	-40(%rsi),%r14
+	mov	-32(%rsi),%r13
+	mov	-24(%rsi),%r12
+	mov	-16(%rsi),%rbp
+	mov	-8(%rsi),%rbx
+	lea	(%rsi),%rsp
 .Lmul4x_epilogue:
 	ret
 .size	bn_mul4x_mont,.-bn_mul4x_mont
@@ -778,14 +795,15 @@ $code.=<<___;
 .type	bn_sqr8x_mont,\@function,6
 .align	32
 bn_sqr8x_mont:
-.Lsqr8x_enter:
 	mov	%rsp,%rax
+.Lsqr8x_enter:
 	push	%rbx
 	push	%rbp
 	push	%r12
 	push	%r13
 	push	%r14
 	push	%r15
+.Lsqr8x_prologue:
 
 	mov	${num}d,%r10d
 	shl	\$3,${num}d		# convert $num to bytes
@@ -798,33 +816,42 @@ bn_sqr8x_mont:
 	# do its job.
 	#
 	lea	-64(%rsp,$num,2),%r11
+	mov	%rsp,%rbp
 	mov	($n0),$n0		# *n0
 	sub	$aptr,%r11
 	and	\$4095,%r11
 	cmp	%r11,%r10
 	jb	.Lsqr8x_sp_alt
-	sub	%r11,%rsp		# align with $aptr
-	lea	-64(%rsp,$num,2),%rsp	# alloca(frame+2*$num)
+	sub	%r11,%rbp		# align with $aptr
+	lea	-64(%rbp,$num,2),%rbp	# future alloca(frame+2*$num)
 	jmp	.Lsqr8x_sp_done
 
 .align	32
 .Lsqr8x_sp_alt:
 	lea	4096-64(,$num,2),%r10	# 4096-frame-2*$num
-	lea	-64(%rsp,$num,2),%rsp	# alloca(frame+2*$num)
+	lea	-64(%rbp,$num,2),%rbp	# future alloca(frame+2*$num)
 	sub	%r10,%r11
 	mov	\$0,%r10
 	cmovc	%r10,%r11
-	sub	%r11,%rsp
+	sub	%r11,%rbp
 .Lsqr8x_sp_done:
-	and	\$-64,%rsp
-	mov	%rax,%r11
-	sub	%rsp,%r11
+	and	\$-64,%rbp
+	mov	%rsp,%r11
+	sub	%rbp,%r11
 	and	\$-4096,%r11
+	lea	(%rbp,%r11),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lsqr8x_page_walk
+	jmp	.Lsqr8x_page_walk_done
+
+.align	16
 .Lsqr8x_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x2e			# predict non-taken
-	jnc	.Lsqr8x_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lsqr8x_page_walk
+.Lsqr8x_page_walk_done:
 
 	mov	$num,%r10
 	neg	$num
@@ -948,30 +975,38 @@ $code.=<<___;
 .type	bn_mulx4x_mont,\@function,6
 .align	32
 bn_mulx4x_mont:
-.Lmulx4x_enter:
 	mov	%rsp,%rax
+.Lmulx4x_enter:
 	push	%rbx
 	push	%rbp
 	push	%r12
 	push	%r13
 	push	%r14
 	push	%r15
+.Lmulx4x_prologue:
 
 	shl	\$3,${num}d		# convert $num to bytes
-	.byte	0x67
 	xor	%r10,%r10
 	sub	$num,%r10		# -$num
 	mov	($n0),$n0		# *n0
-	lea	-72(%rsp,%r10),%rsp	# alloca(frame+$num+8)
-	and	\$-128,%rsp
-	mov	%rax,%r11
-	sub	%rsp,%r11
+	lea	-72(%rsp,%r10),%rbp	# future alloca(frame+$num+8)
+	and	\$-128,%rbp
+	mov	%rsp,%r11
+	sub	%rbp,%r11
 	and	\$-4096,%r11
+	lea	(%rbp,%r11),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lmulx4x_page_walk
+	jmp	.Lmulx4x_page_walk_done
+
+.align	16
 .Lmulx4x_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x66,0x2e		# predict non-taken
-	jnc	.Lmulx4x_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lmulx4x_page_walk
+.Lmulx4x_page_walk_done:
 
 	lea	($bp,$num),%r10
 	##############################################################
@@ -1332,22 +1367,8 @@ mul_handler:
 
 	mov	192($context),%r10	# pull $num
 	mov	8(%rax,%r10,8),%rax	# pull saved stack pointer
-	lea	48(%rax),%rax
-
-	mov	-8(%rax),%rbx
-	mov	-16(%rax),%rbp
-	mov	-24(%rax),%r12
-	mov	-32(%rax),%r13
-	mov	-40(%rax),%r14
-	mov	-48(%rax),%r15
-	mov	%rbx,144($context)	# restore context->Rbx
-	mov	%rbp,160($context)	# restore context->Rbp
-	mov	%r12,216($context)	# restore context->R12
-	mov	%r13,224($context)	# restore context->R13
-	mov	%r14,232($context)	# restore context->R14
-	mov	%r15,240($context)	# restore context->R15
 
-	jmp	.Lcommon_seh_tail
+	jmp	.Lcommon_pop_regs
 .size	mul_handler,.-mul_handler
 
 .type	sqr_handler,\@abi-omnipotent
@@ -1375,15 +1396,21 @@ sqr_handler:
 	cmp	%r10,%rbx		# context->Rip<.Lsqr_body
 	jb	.Lcommon_seh_tail
 
+	mov	4(%r11),%r10d		# HandlerData[1]
+	lea	(%rsi,%r10),%r10	# body label
+	cmp	%r10,%rbx		# context->Rip>=.Lsqr_epilogue
+	jb	.Lcommon_pop_regs
+
 	mov	152($context),%rax	# pull context->Rsp
 
-	mov	4(%r11),%r10d		# HandlerData[1]
+	mov	8(%r11),%r10d		# HandlerData[2]
 	lea	(%rsi,%r10),%r10	# epilogue label
 	cmp	%r10,%rbx		# context->Rip>=.Lsqr_epilogue
 	jae	.Lcommon_seh_tail
 
 	mov	40(%rax),%rax		# pull saved stack pointer
 
+.Lcommon_pop_regs:
 	mov	-8(%rax),%rbx
 	mov	-16(%rax),%rbp
 	mov	-24(%rax),%r12
@@ -1470,13 +1497,15 @@ $code.=<<___;
 .LSEH_info_bn_sqr8x_mont:
 	.byte	9,0,0,0
 	.rva	sqr_handler
-	.rva	.Lsqr8x_body,.Lsqr8x_epilogue	# HandlerData[]
+	.rva	.Lsqr8x_prologue,.Lsqr8x_body,.Lsqr8x_epilogue		# HandlerData[]
+.align	8
 ___
 $code.=<<___ if ($addx);
 .LSEH_info_bn_mulx4x_mont:
 	.byte	9,0,0,0
 	.rva	sqr_handler
-	.rva	.Lmulx4x_body,.Lmulx4x_epilogue	# HandlerData[]
+	.rva	.Lmulx4x_prologue,.Lmulx4x_body,.Lmulx4x_epilogue	# HandlerData[]
+.align	8
 ___
 }
 
diff --git a/crypto/bn/asm/x86_64-mont5.pl b/crypto/bn/asm/x86_64-mont5.pl
index 938e17081803..f1fbb45b532b 100755
--- a/crypto/bn/asm/x86_64-mont5.pl
+++ b/crypto/bn/asm/x86_64-mont5.pl
@@ -86,6 +86,8 @@ $code=<<___;
 .type	bn_mul_mont_gather5,\@function,6
 .align	64
 bn_mul_mont_gather5:
+	mov	${num}d,${num}d
+	mov	%rsp,%rax
 	test	\$7,${num}d
 	jnz	.Lmul_enter
 ___
@@ -97,10 +99,7 @@ $code.=<<___;
 
 .align	16
 .Lmul_enter:
-	mov	${num}d,${num}d
-	mov	%rsp,%rax
 	movd	`($win64?56:8)`(%rsp),%xmm5	# load 7th argument
-	lea	.Linc(%rip),%r10
 	push	%rbx
 	push	%rbp
 	push	%r12
@@ -108,26 +107,36 @@ $code.=<<___;
 	push	%r14
 	push	%r15
 
-	lea	2($num),%r11
-	neg	%r11
-	lea	-264(%rsp,%r11,8),%rsp	# tp=alloca(8*(num+2)+256+8)
-	and	\$-1024,%rsp		# minimize TLB usage
+	neg	$num
+	mov	%rsp,%r11
+	lea	-280(%rsp,$num,8),%r10	# future alloca(8*(num+2)+256+8)
+	neg	$num			# restore $num
+	and	\$-1024,%r10		# minimize TLB usage
 
-	mov	%rax,8(%rsp,$num,8)	# tp[num+1]=%rsp
-.Lmul_body:
 	# Some OSes, *cough*-dows, insist on stack being "wired" to
 	# physical memory in strictly sequential manner, i.e. if stack
 	# allocation spans two pages, then reference to farmost one can
 	# be punishable by SEGV. But page walking can do good even on
 	# other OSes, because it guarantees that villain thread hits
 	# the guard page before it can make damage to innocent one...
-	sub	%rsp,%rax
-	and	\$-4096,%rax
+	sub	%r10,%r11
+	and	\$-4096,%r11
+	lea	(%r10,%r11),%rsp
+	mov	(%rsp),%r11
+	cmp	%r10,%rsp
+	ja	.Lmul_page_walk
+	jmp	.Lmul_page_walk_done
+
 .Lmul_page_walk:
-	mov	(%rsp,%rax),%r11
-	sub	\$4096,%rax
-	.byte	0x2e			# predict non-taken
-	jnc	.Lmul_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r11
+	cmp	%r10,%rsp
+	ja	.Lmul_page_walk
+.Lmul_page_walk_done:
+
+	lea	.Linc(%rip),%r10
+	mov	%rax,8(%rsp,$num,8)	# tp[num+1]=%rsp
+.Lmul_body:
 
 	lea	128($bp),%r12		# reassign $bp (+size optimization)
 ___
@@ -433,6 +442,8 @@ $code.=<<___;
 .type	bn_mul4x_mont_gather5,\@function,6
 .align	32
 bn_mul4x_mont_gather5:
+	.byte	0x67
+	mov	%rsp,%rax
 .Lmul4x_enter:
 ___
 $code.=<<___ if ($addx);
@@ -441,14 +452,13 @@ $code.=<<___ if ($addx);
 	je	.Lmulx4x_enter
 ___
 $code.=<<___;
-	.byte	0x67
-	mov	%rsp,%rax
 	push	%rbx
 	push	%rbp
 	push	%r12
 	push	%r13
 	push	%r14
 	push	%r15
+.Lmul4x_prologue:
 
 	.byte	0x67
 	shl	\$3,${num}d		# convert $num to bytes
@@ -465,32 +475,40 @@ $code.=<<___;
 	# calculated from 7th argument, the index.]
 	#
 	lea	-320(%rsp,$num,2),%r11
+	mov	%rsp,%rbp
 	sub	$rp,%r11
 	and	\$4095,%r11
 	cmp	%r11,%r10
 	jb	.Lmul4xsp_alt
-	sub	%r11,%rsp		# align with $rp
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*num*8+256)
+	sub	%r11,%rbp		# align with $rp
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*num*8+256)
 	jmp	.Lmul4xsp_done
 
 .align	32
 .Lmul4xsp_alt:
 	lea	4096-320(,$num,2),%r10
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*num*8+256)
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*num*8+256)
 	sub	%r10,%r11
 	mov	\$0,%r10
 	cmovc	%r10,%r11
-	sub	%r11,%rsp
+	sub	%r11,%rbp
 .Lmul4xsp_done:
-	and	\$-64,%rsp
-	mov	%rax,%r11
-	sub	%rsp,%r11
+	and	\$-64,%rbp
+	mov	%rsp,%r11
+	sub	%rbp,%r11
 	and	\$-4096,%r11
+	lea	(%rbp,%r11),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lmul4x_page_walk
+	jmp	.Lmul4x_page_walk_done
+
 .Lmul4x_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x2e			# predict non-taken
-	jnc	.Lmul4x_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lmul4x_page_walk
+.Lmul4x_page_walk_done:
 
 	neg	$num
 
@@ -1034,6 +1052,7 @@ $code.=<<___;
 .type	bn_power5,\@function,6
 .align	32
 bn_power5:
+	mov	%rsp,%rax
 ___
 $code.=<<___ if ($addx);
 	mov	OPENSSL_ia32cap_P+8(%rip),%r11d
@@ -1042,13 +1061,13 @@ $code.=<<___ if ($addx);
 	je	.Lpowerx5_enter
 ___
 $code.=<<___;
-	mov	%rsp,%rax
 	push	%rbx
 	push	%rbp
 	push	%r12
 	push	%r13
 	push	%r14
 	push	%r15
+.Lpower5_prologue:
 
 	shl	\$3,${num}d		# convert $num to bytes
 	lea	($num,$num,2),%r10d	# 3*$num
@@ -1063,32 +1082,40 @@ $code.=<<___;
 	# calculated from 7th argument, the index.]
 	#
 	lea	-320(%rsp,$num,2),%r11
+	mov	%rsp,%rbp
 	sub	$rptr,%r11
 	and	\$4095,%r11
 	cmp	%r11,%r10
 	jb	.Lpwr_sp_alt
-	sub	%r11,%rsp		# align with $aptr
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*num*8+256)
+	sub	%r11,%rbp		# align with $aptr
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*num*8+256)
 	jmp	.Lpwr_sp_done
 
 .align	32
 .Lpwr_sp_alt:
 	lea	4096-320(,$num,2),%r10
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*num*8+256)
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*num*8+256)
 	sub	%r10,%r11
 	mov	\$0,%r10
 	cmovc	%r10,%r11
-	sub	%r11,%rsp
+	sub	%r11,%rbp
 .Lpwr_sp_done:
-	and	\$-64,%rsp
-	mov	%rax,%r11
-	sub	%rsp,%r11
+	and	\$-64,%rbp
+	mov	%rsp,%r11
+	sub	%rbp,%r11
 	and	\$-4096,%r11
+	lea	(%rbp,%r11),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lpwr_page_walk
+	jmp	.Lpwr_page_walk_done
+
 .Lpwr_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x2e			# predict non-taken
-	jnc	.Lpwr_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lpwr_page_walk
+.Lpwr_page_walk_done:
 
 	mov	$num,%r10	
 	neg	$num
@@ -2028,6 +2055,7 @@ bn_from_mont8x:
 	push	%r13
 	push	%r14
 	push	%r15
+.Lfrom_prologue:
 
 	shl	\$3,${num}d		# convert $num to bytes
 	lea	($num,$num,2),%r10	# 3*$num in bytes
@@ -2042,32 +2070,40 @@ bn_from_mont8x:
 	# last operation, we use the opportunity to cleanse it.
 	#
 	lea	-320(%rsp,$num,2),%r11
+	mov	%rsp,%rbp
 	sub	$rptr,%r11
 	and	\$4095,%r11
 	cmp	%r11,%r10
 	jb	.Lfrom_sp_alt
-	sub	%r11,%rsp		# align with $aptr
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*$num*8+256)
+	sub	%r11,%rbp		# align with $aptr
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*$num*8+256)
 	jmp	.Lfrom_sp_done
 
 .align	32
 .Lfrom_sp_alt:
 	lea	4096-320(,$num,2),%r10
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*$num*8+256)
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*$num*8+256)
 	sub	%r10,%r11
 	mov	\$0,%r10
 	cmovc	%r10,%r11
-	sub	%r11,%rsp
+	sub	%r11,%rbp
 .Lfrom_sp_done:
-	and	\$-64,%rsp
-	mov	%rax,%r11
-	sub	%rsp,%r11
+	and	\$-64,%rbp
+	mov	%rsp,%r11
+	sub	%rbp,%r11
 	and	\$-4096,%r11
+	lea	(%rbp,%r11),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lfrom_page_walk
+	jmp	.Lfrom_page_walk_done
+
 .Lfrom_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x2e			# predict non-taken
-	jnc	.Lfrom_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lfrom_page_walk
+.Lfrom_page_walk_done:
 
 	mov	$num,%r10
 	neg	$num
@@ -2173,14 +2209,15 @@ $code.=<<___;
 .type	bn_mulx4x_mont_gather5,\@function,6
 .align	32
 bn_mulx4x_mont_gather5:
-.Lmulx4x_enter:
 	mov	%rsp,%rax
+.Lmulx4x_enter:
 	push	%rbx
 	push	%rbp
 	push	%r12
 	push	%r13
 	push	%r14
 	push	%r15
+.Lmulx4x_prologue:
 
 	shl	\$3,${num}d		# convert $num to bytes
 	lea	($num,$num,2),%r10	# 3*$num in bytes
@@ -2197,31 +2234,39 @@ bn_mulx4x_mont_gather5:
 	# calculated from 7th argument, the index.]
 	#
 	lea	-320(%rsp,$num,2),%r11
+	mov	%rsp,%rbp
 	sub	$rp,%r11
 	and	\$4095,%r11
 	cmp	%r11,%r10
 	jb	.Lmulx4xsp_alt
-	sub	%r11,%rsp		# align with $aptr
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*$num*8+256)
+	sub	%r11,%rbp		# align with $aptr
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*$num*8+256)
 	jmp	.Lmulx4xsp_done
 
 .Lmulx4xsp_alt:
 	lea	4096-320(,$num,2),%r10
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*$num*8+256)
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*$num*8+256)
 	sub	%r10,%r11
 	mov	\$0,%r10
 	cmovc	%r10,%r11
-	sub	%r11,%rsp
+	sub	%r11,%rbp
 .Lmulx4xsp_done:	
-	and	\$-64,%rsp		# ensure alignment
-	mov	%rax,%r11
-	sub	%rsp,%r11
+	and	\$-64,%rbp		# ensure alignment
+	mov	%rsp,%r11
+	sub	%rbp,%r11
 	and	\$-4096,%r11
+	lea	(%rbp,%r11),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lmulx4x_page_walk
+	jmp	.Lmulx4x_page_walk_done
+
 .Lmulx4x_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x2e			# predict non-taken
-	jnc	.Lmulx4x_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lmulx4x_page_walk
+.Lmulx4x_page_walk_done:
 
 	##############################################################
 	# Stack layout
@@ -2629,14 +2674,15 @@ $code.=<<___;
 .type	bn_powerx5,\@function,6
 .align	32
 bn_powerx5:
-.Lpowerx5_enter:
 	mov	%rsp,%rax
+.Lpowerx5_enter:
 	push	%rbx
 	push	%rbp
 	push	%r12
 	push	%r13
 	push	%r14
 	push	%r15
+.Lpowerx5_prologue:
 
 	shl	\$3,${num}d		# convert $num to bytes
 	lea	($num,$num,2),%r10	# 3*$num in bytes
@@ -2651,32 +2697,40 @@ bn_powerx5:
 	# calculated from 7th argument, the index.]
 	#
 	lea	-320(%rsp,$num,2),%r11
+	mov	%rsp,%rbp
 	sub	$rptr,%r11
 	and	\$4095,%r11
 	cmp	%r11,%r10
 	jb	.Lpwrx_sp_alt
-	sub	%r11,%rsp		# align with $aptr
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*$num*8+256)
+	sub	%r11,%rbp		# align with $aptr
+	lea	-320(%rbp,$num,2),%rbp	# future alloca(frame+2*$num*8+256)
 	jmp	.Lpwrx_sp_done
 
 .align	32
 .Lpwrx_sp_alt:
 	lea	4096-320(,$num,2),%r10
-	lea	-320(%rsp,$num,2),%rsp	# alloca(frame+2*$num*8+256)
+	lea	-320(%rbp,$num,2),%rbp	# alloca(frame+2*$num*8+256)
 	sub	%r10,%r11
 	mov	\$0,%r10
 	cmovc	%r10,%r11
-	sub	%r11,%rsp
+	sub	%r11,%rbp
 .Lpwrx_sp_done:
-	and	\$-64,%rsp
-	mov	%rax,%r11
-	sub	%rsp,%r11
+	and	\$-64,%rbp
+	mov	%rsp,%r11
+	sub	%rbp,%r11
 	and	\$-4096,%r11
+	lea	(%rbp,%r11),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lpwrx_page_walk
+	jmp	.Lpwrx_page_walk_done
+
 .Lpwrx_page_walk:
-	mov	(%rsp,%r11),%r10
-	sub	\$4096,%r11
-	.byte	0x2e			# predict non-taken
-	jnc	.Lpwrx_page_walk
+	lea	-4096(%rsp),%rsp
+	mov	(%rsp),%r10
+	cmp	%rbp,%rsp
+	ja	.Lpwrx_page_walk
+.Lpwrx_page_walk_done:
 
 	mov	$num,%r10	
 	neg	$num
@@ -3607,9 +3661,14 @@ mul_handler:
 	cmp	%r10,%rbx		# context->Rip<end of prologue label
 	jb	.Lcommon_seh_tail
 
+	mov	4(%r11),%r10d		# HandlerData[1]
+	lea	(%rsi,%r10),%r10	# epilogue label
+	cmp	%r10,%rbx		# context->Rip>=epilogue label
+	jb	.Lcommon_pop_regs
+
 	mov	152($context),%rax	# pull context->Rsp
 
-	mov	4(%r11),%r10d		# HandlerData[1]
+	mov	8(%r11),%r10d		# HandlerData[2]
 	lea	(%rsi,%r10),%r10	# epilogue label
 	cmp	%r10,%rbx		# context->Rip>=epilogue label
 	jae	.Lcommon_seh_tail
@@ -3621,11 +3680,11 @@ mul_handler:
 	mov	192($context),%r10	# pull $num
 	mov	8(%rax,%r10,8),%rax	# pull saved stack pointer
 
-	jmp	.Lbody_proceed
+	jmp	.Lcommon_pop_regs
 
 .Lbody_40:
 	mov	40(%rax),%rax		# pull saved stack pointer
-.Lbody_proceed:
+.Lcommon_pop_regs:
 	mov	-8(%rax),%rbx
 	mov	-16(%rax),%rbp
 	mov	-24(%rax),%r12
@@ -3716,34 +3775,34 @@ $code.=<<___;
 .LSEH_info_bn_mul_mont_gather5:
 	.byte	9,0,0,0
 	.rva	mul_handler
-	.rva	.Lmul_body,.Lmul_epilogue		# HandlerData[]
+	.rva	.Lmul_body,.Lmul_body,.Lmul_epilogue		# HandlerData[]
 .align	8
 .LSEH_info_bn_mul4x_mont_gather5:
 	.byte	9,0,0,0
 	.rva	mul_handler
-	.rva	.Lmul4x_body,.Lmul4x_epilogue		# HandlerData[]
+	.rva	.Lmul4x_prologue,.Lmul4x_body,.Lmul4x_epilogue		# HandlerData[]
 .align	8
 .LSEH_info_bn_power5:
 	.byte	9,0,0,0
 	.rva	mul_handler
-	.rva	.Lpower5_body,.Lpower5_epilogue		# HandlerData[]
+	.rva	.Lpower5_prologue,.Lpower5_body,.Lpower5_epilogue	# HandlerData[]
 .align	8
 .LSEH_info_bn_from_mont8x:
 	.byte	9,0,0,0
 	.rva	mul_handler
-	.rva	.Lfrom_body,.Lfrom_epilogue		# HandlerData[]
+	.rva	.Lfrom_prologue,.Lfrom_body,.Lfrom_epilogue		# HandlerData[]
 ___
 $code.=<<___ if ($addx);
 .align	8
 .LSEH_info_bn_mulx4x_mont_gather5:
 	.byte	9,0,0,0
 	.rva	mul_handler
-	.rva	.Lmulx4x_body,.Lmulx4x_epilogue		# HandlerData[]
+	.rva	.Lmulx4x_prologue,.Lmulx4x_body,.Lmulx4x_epilogue	# HandlerData[]
 .align	8
 .LSEH_info_bn_powerx5:
 	.byte	9,0,0,0
 	.rva	mul_handler
-	.rva	.Lpowerx5_body,.Lpowerx5_epilogue	# HandlerData[]
+	.rva	.Lpowerx5_prologue,.Lpowerx5_body,.Lpowerx5_epilogue	# HandlerData[]
 ___
 $code.=<<___;
 .align	8
diff --git a/crypto/bn/bn.h b/crypto/bn/bn.h
index 86264ae6315f..633d1b1f6013 100644
--- a/crypto/bn/bn.h
+++ b/crypto/bn/bn.h
@@ -842,6 +842,8 @@ int RAND_pseudo_bytes(unsigned char *buf, int num);
                         if (*(ftl--)) break; \
                 (a)->top = tmp_top; \
                 } \
+        if ((a)->top == 0) \
+            (a)->neg = 0; \
         bn_pollute(a); \
         }
 
diff --git a/crypto/bn/bn_div.c b/crypto/bn/bn_div.c
index 72e6ce3f74c0..bc37671cf138 100644
--- a/crypto/bn/bn_div.c
+++ b/crypto/bn/bn_div.c
@@ -155,7 +155,7 @@ int BN_div(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d,
         ({  asm volatile (                      \
                 "divl   %4"                     \
                 : "=a"(q), "=d"(rem)            \
-                : "a"(n1), "d"(n0), "g"(d0)     \
+                : "a"(n1), "d"(n0), "r"(d0)     \
                 : "cc");                        \
             q;                                  \
         })
@@ -170,7 +170,7 @@ int BN_div(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d,
         ({  asm volatile (                      \
                 "divq   %4"                     \
                 : "=a"(q), "=d"(rem)            \
-                : "a"(n1), "d"(n0), "g"(d0)     \
+                : "a"(n1), "d"(n0), "r"(d0)     \
                 : "cc");                        \
             q;                                  \
         })
diff --git a/crypto/bn/bn_lib.c b/crypto/bn/bn_lib.c
index 80105fff410c..10b78f512607 100644
--- a/crypto/bn/bn_lib.c
+++ b/crypto/bn/bn_lib.c
@@ -569,7 +569,7 @@ void BN_clear(BIGNUM *a)
 {
     bn_check_top(a);
     if (a->d != NULL)
-        memset(a->d, 0, a->dmax * sizeof(a->d[0]));
+        OPENSSL_cleanse(a->d, a->dmax * sizeof(a->d[0]));
     a->top = 0;
     a->neg = 0;
 }
diff --git a/crypto/bn/bn_print.c b/crypto/bn/bn_print.c
index bfa31efc5621..f121fb6e9a08 100644
--- a/crypto/bn/bn_print.c
+++ b/crypto/bn/bn_print.c
@@ -72,12 +72,9 @@ char *BN_bn2hex(const BIGNUM *a)
     char *buf;
     char *p;
 
-    if (a->neg && BN_is_zero(a)) {
-        /* "-0" == 3 bytes including NULL terminator */
-        buf = OPENSSL_malloc(3);
-    } else {
-        buf = OPENSSL_malloc(a->top * BN_BYTES * 2 + 2);
-    }
+    if (BN_is_zero(a))
+        return OPENSSL_strdup("0");
+    buf = OPENSSL_malloc(a->top * BN_BYTES * 2 + 2);
     if (buf == NULL) {
         BNerr(BN_F_BN_BN2HEX, ERR_R_MALLOC_FAILURE);
         goto err;
@@ -111,6 +108,7 @@ char *BN_bn2dec(const BIGNUM *a)
     char *p;
     BIGNUM *t = NULL;
     BN_ULONG *bn_data = NULL, *lp;
+    int bn_data_num;
 
     /*-
      * get an upper bound for the length of the decimal integer
@@ -120,9 +118,9 @@ char *BN_bn2dec(const BIGNUM *a)
      */
     i = BN_num_bits(a) * 3;
     num = (i / 10 + i / 1000 + 1) + 1;
-    bn_data =
-        (BN_ULONG *)OPENSSL_malloc((num / BN_DEC_NUM + 1) * sizeof(BN_ULONG));
-    buf = (char *)OPENSSL_malloc(num + 3);
+    bn_data_num = num / BN_DEC_NUM + 1;
+    bn_data = OPENSSL_malloc(bn_data_num * sizeof(BN_ULONG));
+    buf = OPENSSL_malloc(num + 3);
     if ((buf == NULL) || (bn_data == NULL)) {
         BNerr(BN_F_BN_BN2DEC, ERR_R_MALLOC_FAILURE);
         goto err;
@@ -140,9 +138,12 @@ char *BN_bn2dec(const BIGNUM *a)
         if (BN_is_negative(t))
             *p++ = '-';
 
-        i = 0;
         while (!BN_is_zero(t)) {
+            if (lp - bn_data >= bn_data_num)
+                goto err;
             *lp = BN_div_word(t, BN_DEC_CONV);
+            if (*lp == (BN_ULONG)-1)
+                goto err;
             lp++;
         }
         lp--;
@@ -240,10 +241,12 @@ int BN_hex2bn(BIGNUM **bn, const char *a)
     }
     ret->top = h;
     bn_correct_top(ret);
-    ret->neg = neg;
 
     *bn = ret;
     bn_check_top(ret);
+    /* Don't set the negative flag if it's zero. */
+    if (ret->top != 0)
+        ret->neg = neg;
     return (num);
  err:
     if (*bn == NULL)
@@ -295,7 +298,7 @@ int BN_dec2bn(BIGNUM **bn, const char *a)
     if (j == BN_DEC_NUM)
         j = 0;
     l = 0;
-    while (*a) {
+    while (--i >= 0) {
         l *= 10;
         l += *a - '0';
         a++;
@@ -306,11 +309,13 @@ int BN_dec2bn(BIGNUM **bn, const char *a)
             j = 0;
         }
     }
-    ret->neg = neg;
 
     bn_correct_top(ret);
     *bn = ret;
     bn_check_top(ret);
+    /* Don't set the negative flag if it's zero. */
+    if (ret->top != 0)
+        ret->neg = neg;
     return (num);
  err:
     if (*bn == NULL)
@@ -321,6 +326,7 @@ int BN_dec2bn(BIGNUM **bn, const char *a)
 int BN_asc2bn(BIGNUM **bn, const char *a)
 {
     const char *p = a;
+
     if (*p == '-')
         p++;
 
@@ -331,7 +337,8 @@ int BN_asc2bn(BIGNUM **bn, const char *a)
         if (!BN_dec2bn(bn, p))
             return 0;
     }
-    if (*a == '-')
+    /* Don't set the negative flag if it's zero. */
+    if (*a == '-' && (*bn)->top != 0)
         (*bn)->neg = 1;
     return 1;
 }
diff --git a/crypto/bn/bn_rand.c b/crypto/bn/bn_rand.c
index f9fb2e9e45e0..60d3f2260ba1 100644
--- a/crypto/bn/bn_rand.c
+++ b/crypto/bn/bn_rand.c
@@ -121,15 +121,14 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
     int ret = 0, bit, bytes, mask;
     time_t tim;
 
-    if (bits < 0 || (bits == 1 && top > 0)) {
-        BNerr(BN_F_BNRAND, BN_R_BITS_TOO_SMALL);
-        return 0;
-    }
-
     if (bits == 0) {
+        if (top != -1 || bottom != 0)
+            goto toosmall;
         BN_zero(rnd);
         return 1;
     }
+    if (bits < 0 || (bits == 1 && top > 0))
+        goto toosmall;
 
     bytes = (bits + 7) / 8;
     bit = (bits - 1) % 8;
@@ -145,13 +144,9 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
     time(&tim);
     RAND_add(&tim, sizeof(tim), 0.0);
 
-    if (pseudorand) {
-        if (RAND_pseudo_bytes(buf, bytes) == -1)
-            goto err;
-    } else {
-        if (RAND_bytes(buf, bytes) <= 0)
-            goto err;
-    }
+    /* We ignore the value of pseudorand and always call RAND_bytes */
+    if (RAND_bytes(buf, bytes) <= 0)
+        goto err;
 
 #if 1
     if (pseudorand == 2) {
@@ -199,6 +194,10 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
     }
     bn_check_top(rnd);
     return (ret);
+
+toosmall:
+    BNerr(BN_F_BNRAND, BN_R_BITS_TOO_SMALL);
+    return 0;
 }
 
 int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
diff --git a/crypto/bn/bn_word.c b/crypto/bn/bn_word.c
index b031a60b5bf8..9b5f9cb98c3a 100644
--- a/crypto/bn/bn_word.c
+++ b/crypto/bn/bn_word.c
@@ -72,10 +72,32 @@ BN_ULONG BN_mod_word(const BIGNUM *a, BN_ULONG w)
     if (w == 0)
         return (BN_ULONG)-1;
 
+#ifndef BN_LLONG
+    /*
+     * If |w| is too long and we don't have BN_ULLONG then we need to fall
+     * back to using BN_div_word
+     */
+    if (w > ((BN_ULONG)1 << BN_BITS4)) {
+        BIGNUM *tmp = BN_dup(a);
+        if (tmp == NULL)
+            return (BN_ULONG)-1;
+
+        ret = BN_div_word(tmp, w);
+        BN_free(tmp);
+
+        return ret;
+    }
+#endif
+
     bn_check_top(a);
     w &= BN_MASK2;
     for (i = a->top - 1; i >= 0; i--) {
 #ifndef BN_LLONG
+        /*
+         * We can assume here that | w <= ((BN_ULONG)1 << BN_BITS4) | and so
+         * | ret < ((BN_ULONG)1 << BN_BITS4) | and therefore the shifts here are
+         * safe and will not overflow
+         */
         ret = ((ret << BN_BITS4) | ((a->d[i] >> BN_BITS4) & BN_MASK2l)) % w;
         ret = ((ret << BN_BITS4) | (a->d[i] & BN_MASK2l)) % w;
 #else
diff --git a/crypto/bn/bntest.c b/crypto/bn/bntest.c
index 1e35988022bb..a327b1a647b2 100644
--- a/crypto/bn/bntest.c
+++ b/crypto/bn/bntest.c
@@ -514,7 +514,7 @@ static void print_word(BIO *bp, BN_ULONG w)
 int test_div_word(BIO *bp)
 {
     BIGNUM a, b;
-    BN_ULONG r, s;
+    BN_ULONG r, rmod, s;
     int i;
 
     BN_init(&a);
@@ -528,8 +528,14 @@ int test_div_word(BIO *bp)
 
         s = b.d[0];
         BN_copy(&b, &a);
+        rmod = BN_mod_word(&b, s);
         r = BN_div_word(&b, s);
 
+        if (rmod != r) {
+            fprintf(stderr, "Mod (word) test failed!\n");
+            return 0;
+        }
+
         if (bp != NULL) {
             if (!results) {
                 BN_print(bp, &a);