From 7298b650cc56e03c9ac827df7b6a28d0532a68d1 Mon Sep 17 00:00:00 2001
From: Henry Case <kris@amongbytes.com>
Date: Wed, 15 May 2019 18:03:35 +0100
Subject: [PATCH] Adds go.mod (#21)

* Reset Makefile after adding go.mod
* Remove ``build`` directory
* Simiplifies makefile
* shake: Make xorIn copyOut platform specific
---
 .travis.yml                 |   4 +
 Makefile                    |  38 ++------
 go.mod                      |   3 +
 hash/shake/sha3.go          |   8 +-
 hash/shake/sha3_test.go     | 182 ++++++++++++++++--------------------
 hash/shake/xor_generic.go   |   8 +-
 hash/shake/xor_unaligned.go |   8 +-
 7 files changed, 107 insertions(+), 144 deletions(-)
 create mode 100644 go.mod

diff --git a/.travis.yml b/.travis.yml
index 4ca8348..a03c8e3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,9 @@
 sudo: required
 language: go
+go:
+  - 1.11.x
+  - 1.12.x
+  - master
 
 matrix:
   include:
diff --git a/Makefile b/Makefile
index da7812c..afec0cd 100644
--- a/Makefile
+++ b/Makefile
@@ -2,8 +2,6 @@
 MK_FILE_PATH = $(lastword $(MAKEFILE_LIST))
 PRJ_DIR      = $(abspath $(dir $(MK_FILE_PATH)))
 GO           ?= go
-GOPATH_LOCAL = $(PRJ_DIR)/build/
-GOPATH_DIR   = src/github.com/henrydcase/nobs
 VENDOR_DIR   = tls_vendor
 OPTS         ?= -v
 NOASM        ?=
@@ -31,37 +29,19 @@ ifeq ($(DBG),1)
 	OPTS_ENV+= GOTRACEBACK=crash	# enable core dumps
 endif
 
-TARGETS ?= \
-	dh   \
-	drbg \
-	ec \
-	hash \
-	kem \
-	utils
-
-prep-%:
-	mkdir -p $(GOPATH_LOCAL)/$(GOPATH_DIR)
-	cp -rf $* $(GOPATH_LOCAL)/$(GOPATH_DIR)/$*
-
-make_dirs:
-	mkdir -p $(GOPATH_LOCAL)/$(GOPATH_DIR)
-	cp -rf etc $(GOPATH_LOCAL)/$(GOPATH_DIR)
-
-test: clean make_dirs $(addprefix prep-,$(TARGETS))
-	cd $(GOPATH_LOCAL); $(OPTS_ENV) GOPATH=$(GOPATH_LOCAL) go test $(OPTS) $(TEST_PATH)
+test: 
+	$(OPTS_ENV) $(GO) test $(OPTS) $(TEST_PATH)
 
 cover:
-	cd $(GOPATH_LOCAL); $(OPTS_ENV) GOPATH=$(GOPATH_LOCAL) go test \
-		-race -coverprofile=coverage_$(NOASM).txt -covermode=atomic $(OPTS) $(TEST_PATH)
-	cat $(GOPATH_LOCAL)/coverage_$(NOASM).txt >> coverage.txt
+	$(GO) test \
+		-coverprofile=coverage.txt -covermode=atomic $(OPTS) $(TEST_PATH)
 
-bench: clean $(addprefix prep-,$(TARGETS))
-	cd $(GOPATH_LOCAL); GOCACHE=$(GOCACHE) GOPATH=$(GOPATH_LOCAL) $(GO) test \
-		$(BENCH_OPTS) $(TEST_PATH)
+bench:
+	$(GO) test $(BENCH_OPTS) $(TEST_PATH)
 
 clean:
-	rm -rf $(GOPATH_LOCAL)
 	rm -rf $(VENDOR_DIR)
+	rm -rf coverage.txt
 
 vendor-sidh-for-tls: clean
 	mkdir -p $(VENDOR_DIR)/github_com/henrydcase/nobs/
@@ -69,7 +49,7 @@ vendor-sidh-for-tls: clean
 	find $(VENDOR_DIR) -type f -print0 -name "*.go" | xargs -0 sed -i 's/github\.com/github_com/g'
 
 pprof-cpu:
-	$(GO) tool pprof $(GOPATH_LOCAL)/cpu.out
+	$(GO) tool pprof cpu.out
 
 pprof-mem:
-	$(GO) tool pprof $(GOPATH_LOCAL)/mem0.out
+	$(GO) tool pprof mem0.out
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..867b7fc
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/henrydcase/nobs
+
+go 1.12
diff --git a/hash/shake/sha3.go b/hash/shake/sha3.go
index 8c8a945..2c01bb8 100644
--- a/hash/shake/sha3.go
+++ b/hash/shake/sha3.go
@@ -83,7 +83,7 @@ func (d *state) permute() {
 	case spongeAbsorbing:
 		// If we're absorbing, we need to xor the input into the state
 		// before applying the permutation.
-		xorInUnaligned(d, d.buf)
+		xorIn(d, d.buf)
 		d.buf = d.storage[:0]
 		keccakF1600(&d.a)
 	case spongeSqueezing:
@@ -91,7 +91,7 @@ func (d *state) permute() {
 		// copying more output.
 		keccakF1600(&d.a)
 		d.buf = d.storage[:d.rate]
-		copyOutUnaligned(d, d.buf)
+		copyOut(d, d.buf)
 	}
 }
 
@@ -119,7 +119,7 @@ func (d *state) padAndPermute(dsbyte byte) {
 	d.permute()
 	d.state = spongeSqueezing
 	d.buf = d.storage[:d.rate]
-	copyOutUnaligned(d, d.buf)
+	copyOut(d, d.buf)
 }
 
 // Write absorbs more data into the hash's state. It produces an error
@@ -136,7 +136,7 @@ func (d *state) Write(p []byte) (written int, err error) {
 	for len(p) > 0 {
 		if len(d.buf) == 0 && len(p) >= d.rate {
 			// The fast path; absorb a full "rate" bytes of input and apply the permutation.
-			xorInUnaligned(d, p[:d.rate])
+			xorIn(d, p[:d.rate])
 			p = p[d.rate:]
 			keccakF1600(&d.a)
 		} else {
diff --git a/hash/shake/sha3_test.go b/hash/shake/sha3_test.go
index a649e19..774d02f 100644
--- a/hash/shake/sha3_test.go
+++ b/hash/shake/sha3_test.go
@@ -22,11 +22,6 @@ import (
 	"testing"
 )
 
-var (
-	xorIn   = xorInUnaligned
-	copyOut = copyOutUnaligned
-)
-
 const (
 	testString  = "brekeccakkeccak koax koax"
 	katFilename = "testdata/keccakKats.json.deflate"
@@ -68,66 +63,53 @@ type KeccakKats struct {
 	}
 }
 
-func testUnalignedAndGeneric(t *testing.T, testf func(impl string)) {
-	xorInOrig, copyOutOrig := xorIn, copyOut
-	xorIn, copyOut = xorInGeneric, copyOutGeneric
-	testf("generic")
-	if xorImplementationUnaligned != "generic" {
-		xorIn, copyOut = xorInGeneric, copyOutGeneric
-		testf("unaligned")
-	}
-	xorIn, copyOut = xorInOrig, copyOutOrig
-}
-
 // TestKeccakKats tests the SHA-3 and Shake implementations against all the
 // ShortMsgKATs from https://github.com/gvanas/KeccakCodePackage
 // (The testvectors are stored in keccakKats.json.deflate due to their length.)
 func TestKeccakKats(t *testing.T) {
-	testUnalignedAndGeneric(t, func(impl string) {
-		// Read the KATs.
-		deflated, err := os.Open(katFilename)
-		if err != nil {
-			t.Errorf("error opening %s: %s", katFilename, err)
-		}
-		file := flate.NewReader(deflated)
-		dec := json.NewDecoder(file)
-		var katSet KeccakKats
-		err = dec.Decode(&katSet)
-		if err != nil {
-			t.Errorf("error decoding KATs: %s", err)
-		}
+	// Read the KATs.
+	deflated, err := os.Open(katFilename)
+	if err != nil {
+		t.Errorf("error opening %s: %s", katFilename, err)
+	}
+	file := flate.NewReader(deflated)
+	dec := json.NewDecoder(file)
+	var katSet KeccakKats
+	err = dec.Decode(&katSet)
+	if err != nil {
+		t.Errorf("error decoding KATs: %s", err)
+	}
 
-		for algo, v := range testShakes {
-			for _, kat := range katSet.Kats[algo] {
-				N, err := hex.DecodeString(kat.N)
-				if err != nil {
-					t.Errorf("error decoding KAT: %s", err)
-				}
-
-				S, err := hex.DecodeString(kat.S)
-				if err != nil {
-					t.Errorf("error decoding KAT: %s", err)
-				}
-				d := v.constructor(N, S)
-				in, err := hex.DecodeString(kat.Message)
-				if err != nil {
-					t.Errorf("error decoding KAT: %s", err)
-				}
-
-				d.Write(in[:kat.Length/8])
-				out := make([]byte, len(kat.Digest)/2)
-				d.Read(out)
-				got := strings.ToUpper(hex.EncodeToString(out))
-				if got != kat.Digest {
-					t.Errorf("function=%s, implementation=%s, length=%d N:%s\n S:%s\nmessage:\n %s \ngot:\n  %s\nwanted:\n %s",
-						algo, impl, kat.Length, kat.N, kat.S, kat.Message, got, kat.Digest)
-					t.Logf("wanted %+v", kat)
-					t.FailNow()
-				}
-				continue
+	for algo, v := range testShakes {
+		for _, kat := range katSet.Kats[algo] {
+			N, err := hex.DecodeString(kat.N)
+			if err != nil {
+				t.Errorf("error decoding KAT: %s", err)
 			}
+
+			S, err := hex.DecodeString(kat.S)
+			if err != nil {
+				t.Errorf("error decoding KAT: %s", err)
+			}
+			d := v.constructor(N, S)
+			in, err := hex.DecodeString(kat.Message)
+			if err != nil {
+				t.Errorf("error decoding KAT: %s", err)
+			}
+
+			d.Write(in[:kat.Length/8])
+			out := make([]byte, len(kat.Digest)/2)
+			d.Read(out)
+			got := strings.ToUpper(hex.EncodeToString(out))
+			if got != kat.Digest {
+				t.Errorf("function=%s, length=%d N:%s\n S:%s\nmessage:\n %s \ngot:\n  %s\nwanted:\n %s",
+					algo, kat.Length, kat.N, kat.S, kat.Message, got, kat.Digest)
+				t.Logf("wanted %+v", kat)
+				t.FailNow()
+			}
+			continue
 		}
-	})
+	}
 }
 
 // TestKeccak does a basic test of the non-standardized Keccak hash functions.
@@ -158,37 +140,35 @@ func TestKeccak(t *testing.T) {
 // TestUnalignedWrite tests that writing data in an arbitrary pattern with
 // small input buffers.
 func TestUnalignedWrite(t *testing.T) {
-	testUnalignedAndGeneric(t, func(impl string) {
-		buf := sequentialBytes(0x10000)
+	buf := sequentialBytes(0x10000)
 
-		// Same for SHAKE
-		for alg, df := range testShakes {
-			want := make([]byte, 16)
-			got := make([]byte, 16)
-			d := df.constructor([]byte(df.defAlgoName), []byte(df.defCustomStr))
+	// Same for SHAKE
+	for alg, df := range testShakes {
+		want := make([]byte, 16)
+		got := make([]byte, 16)
+		d := df.constructor([]byte(df.defAlgoName), []byte(df.defCustomStr))
 
-			d.Reset()
-			d.Write(buf)
-			d.Read(want)
-			d.Reset()
-			for i := 0; i < len(buf); {
-				// Cycle through offsets which make a 137 byte sequence.
-				// Because 137 is prime this sequence should exercise all corner cases.
-				offsets := [17]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 1}
-				for _, j := range offsets {
-					if v := len(buf) - i; v < j {
-						j = v
-					}
-					d.Write(buf[i : i+j])
-					i += j
+		d.Reset()
+		d.Write(buf)
+		d.Read(want)
+		d.Reset()
+		for i := 0; i < len(buf); {
+			// Cycle through offsets which make a 137 byte sequence.
+			// Because 137 is prime this sequence should exercise all corner cases.
+			offsets := [17]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 1}
+			for _, j := range offsets {
+				if v := len(buf) - i; v < j {
+					j = v
 				}
-			}
-			d.Read(got)
-			if !bytes.Equal(got, want) {
-				t.Errorf("Unaligned writes, implementation=%s, alg=%s\ngot %q, want %q", impl, alg, got, want)
+				d.Write(buf[i : i+j])
+				i += j
 			}
 		}
-	})
+		d.Read(got)
+		if !bytes.Equal(got, want) {
+			t.Errorf("Unaligned writes, alg=%s\ngot %q, want %q", alg, got, want)
+		}
+	}
 }
 
 /* TODO: To redesign those tests and unlock
@@ -231,26 +211,24 @@ func TestAppendNoRealloc(t *testing.T) {
 // TestSqueezing checks that squeezing the full output a single time produces
 // the same output as repeatedly squeezing the instance.
 func TestSqueezing(t *testing.T) {
-	testUnalignedAndGeneric(t, func(impl string) {
-		for algo, v := range testShakes {
-			d0 := v.constructor([]byte(v.defAlgoName), []byte(v.defCustomStr))
-			d0.Write([]byte(testString))
-			ref := make([]byte, 32)
-			d0.Read(ref)
+	for algo, v := range testShakes {
+		d0 := v.constructor([]byte(v.defAlgoName), []byte(v.defCustomStr))
+		d0.Write([]byte(testString))
+		ref := make([]byte, 32)
+		d0.Read(ref)
 
-			d1 := v.constructor([]byte(v.defAlgoName), []byte(v.defCustomStr))
-			d1.Write([]byte(testString))
-			var multiple []byte
-			for range ref {
-				one := make([]byte, 1)
-				d1.Read(one)
-				multiple = append(multiple, one...)
-			}
-			if !bytes.Equal(ref, multiple) {
-				t.Errorf("%s (%s): squeezing %d bytes one at a time failed", algo, impl, len(ref))
-			}
+		d1 := v.constructor([]byte(v.defAlgoName), []byte(v.defCustomStr))
+		d1.Write([]byte(testString))
+		var multiple []byte
+		for range ref {
+			one := make([]byte, 1)
+			d1.Read(one)
+			multiple = append(multiple, one...)
 		}
-	})
+		if !bytes.Equal(ref, multiple) {
+			t.Errorf("%s : squeezing %d bytes one at a time failed", algo, len(ref))
+		}
+	}
 }
 
 // sequentialBytes produces a buffer of size consecutive bytes 0x00, 0x01, ..., used for testing.
diff --git a/hash/shake/xor_generic.go b/hash/shake/xor_generic.go
index 9292820..867cab3 100644
--- a/hash/shake/xor_generic.go
+++ b/hash/shake/xor_generic.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build !amd64,!386,!ppc64le
+
 package shake
 
 import "encoding/binary"
@@ -9,7 +11,7 @@ import "encoding/binary"
 // xorInGeneric xors the bytes in buf into the state; it
 // makes no non-portable assumptions about memory layout
 // or alignment.
-func xorInGeneric(d *state, buf []byte) {
+func xorIn(d *state, buf []byte) {
 	n := len(buf) / 8
 
 	for i := 0; i < n; i++ {
@@ -20,11 +22,9 @@ func xorInGeneric(d *state, buf []byte) {
 }
 
 // copyOutGeneric copies ulint64s to a byte buffer.
-func copyOutGeneric(d *state, b []byte) {
+func copyOut(d *state, b []byte) {
 	for i := 0; len(b) >= 8; i++ {
 		binary.LittleEndian.PutUint64(b, d.a[i])
 		b = b[8:]
 	}
 }
-
-const xorImplementationGeneric = "generic"
diff --git a/hash/shake/xor_unaligned.go b/hash/shake/xor_unaligned.go
index 9de3d4c..d7348f0 100644
--- a/hash/shake/xor_unaligned.go
+++ b/hash/shake/xor_unaligned.go
@@ -2,14 +2,14 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build amd64 arm64 386 ppc64le
+// +build amd64 386 ppc64le
 // +build !appengine
 
 package shake
 
 import "unsafe"
 
-func xorInUnaligned(d *state, buf []byte) {
+func xorIn(d *state, buf []byte) {
 	bw := (*[maxRate / 8]uint64)(unsafe.Pointer(&buf[0]))
 	n := len(buf)
 	if n >= 72 {
@@ -45,9 +45,7 @@ func xorInUnaligned(d *state, buf []byte) {
 	}
 }
 
-func copyOutUnaligned(d *state, buf []byte) {
+func copyOut(d *state, buf []byte) {
 	ab := (*[maxRate]uint8)(unsafe.Pointer(&d.a[0]))
 	copy(buf, ab[:])
 }
-
-const xorImplementationUnaligned = "unaligned"