From 1a75fd65ca477d8bcf21b8f069b04e855eb3305d Mon Sep 17 00:00:00 2001
From: Sun Yimin <emmansun@users.noreply.github.com>
Date: Fri, 15 Jul 2022 11:48:44 +0800
Subject: [PATCH] zuc: add comment and fix a bug

---
 sm3/sm3.go             | 2 +-
 zuc/eia.go             | 2 ++
 zuc/eia256.go          | 4 ++++
 zuc/eia256_asm_arm64.s | 4 ++--
 4 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/sm3/sm3.go b/sm3/sm3.go
index c1bb8bb..dd1707e 100644
--- a/sm3/sm3.go
+++ b/sm3/sm3.go
@@ -117,7 +117,7 @@ func New() hash.Hash {
 	return d
 }
 
-// Sum appends the current hash to b and returns the resulting slice.
+// Sum appends the current hash to in and returns the resulting slice.
 // It does not change the underlying hash state.
 func (d *digest) Sum(in []byte) []byte {
 	// Make a copy of d so that caller can keep writing and summing.
diff --git a/zuc/eia.go b/zuc/eia.go
index 8018776..73d1313 100644
--- a/zuc/eia.go
+++ b/zuc/eia.go
@@ -206,6 +206,8 @@ func (m *ZUC128Mac) Finish(p []byte, nbits int) []byte {
 	return digest[:]
 }
 
+// Sum appends the current hash to in and returns the resulting slice.
+// It does not change the underlying hash state.
 func (m *ZUC128Mac) Sum(in []byte) []byte {
 	// Make a copy of d so that caller can keep writing and summing.
 	d0 := *m
diff --git a/zuc/eia256.go b/zuc/eia256.go
index 123af21..c45c301 100644
--- a/zuc/eia256.go
+++ b/zuc/eia256.go
@@ -231,9 +231,13 @@ func (m *ZUC256Mac) Finish(p []byte, nbits int) []byte {
 	return digest[:]
 }
 
+// Sum appends the current hash to in and returns the resulting slice.
+// It does not change the underlying hash state.
 func (m *ZUC256Mac) Sum(in []byte) []byte {
 	// Make a copy of d so that caller can keep writing and summing.
 	d0 := *m
+	d0.t = make([]uint32, len(m.t))
+	copy(d0.t, m.t)
 	hash := d0.checkSum(0, 0)
 	return append(in, hash[:]...)
 }
diff --git a/zuc/eia256_asm_arm64.s b/zuc/eia256_asm_arm64.s
index a0b92a6..6acb36a 100644
--- a/zuc/eia256_asm_arm64.s
+++ b/zuc/eia256_asm_arm64.s
@@ -69,7 +69,7 @@ TEXT ·eia256RoundTag8(SB),NOSPLIT,$0
 	MOVD ks+8(FP), BX
 	MOVD p+16(FP), CX
 
-    LOAD_GLOBAL_DATA()
+	LOAD_GLOBAL_DATA()
 
 	// Reverse data bytes
 	VLD1 (CX), [XDATA.B16]
@@ -148,7 +148,7 @@ TEXT ·eia256RoundTag16(SB),NOSPLIT,$0
 	MOVD ks+8(FP), BX
 	MOVD p+16(FP), CX
 
-    LOAD_GLOBAL_DATA()
+	LOAD_GLOBAL_DATA()
 
 	// Reverse data bytes
 	VLD1 (CX), [XDATA.B16]