Merge pull request #11 from tdakkota/feat/optmize-allocations

feat(ige): reduce allocations for DecryptBlocks/EncryptBlocks

.gitignore

@@ -0,0 +1,22 @@
+# IntelliJ project files
+.idea
+*.iml
+out
+gen
+### Go template
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+

decrypt.go

@@ -48,3 +48,14 @@ func (i *igeDecrypter) CryptBlocks(dst, src []byte) {
 		c = t
 	}
 }
+
+// DecryptBlocks is a simple shorthand for IGE decrypting.
+// Note: unlike NewIGEDecrypter, DecryptBlocks does NOT COPY iv.
+// So you must not modify passed iv.
+func DecryptBlocks(b cipher.Block, iv, dst, src []byte) {
+	if err := checkIV(b, iv); err != nil {
+		panic(err.Error())
+	}
+	dec := igeDecrypter{block: b, iv: iv}
+	dec.CryptBlocks(dst, src)
+}

decrypt_test.go

@@ -3,6 +3,7 @@ package ige
 import (
 	"bytes"
 	"crypto/aes"
+	"fmt"
 	"testing"
 )
 
@@ -52,6 +53,23 @@ func TestDecrypterCryptBlocks(t *testing.T) {
 	}
 }
 
+func TestDecryptBlocks(t *testing.T) {
+	for a, v := range TestVectors {
+		out := make([]byte, len(v.Ciphertext))
+
+		c, err := aes.NewCipher(v.Key)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		DecryptBlocks(c, v.IV, out, v.Ciphertext)
+
+		if !bytes.Equal(out, v.Plaintext) {
+			t.Fatalf("test vector %d has wrong ciphertext\n", a+1)
+		}
+	}
+}
+
 func TestDecryptCryptBlocksPanicSrc(t *testing.T) {
 	c, err := aes.NewCipher(make([]byte, 16))
 	if err != nil {
@@ -83,3 +101,38 @@ func TestDecryptCryptBlocksPanicDst(t *testing.T) {
 	i := NewIGEDecrypter(c, make([]byte, 32))
 	i.CryptBlocks(make([]byte, 1), make([]byte, 16))
 }
+
+func BenchmarkDecryptBlocks(b *testing.B) {
+	for _, payload := range []int{
+		16,
+		128,
+		1024,
+		8192,
+		64 * 1024,
+		512 * 1024,
+	} {
+		b.Run(fmt.Sprintf("%d", payload), benchDecrypt(payload))
+	}
+}
+
+func benchDecrypt(n int) func(b *testing.B) {
+	return func(b *testing.B) {
+		b.Helper()
+
+		src := make([]byte, n)
+		dst := make([]byte, n)
+
+		b.ReportAllocs()
+		b.SetBytes(int64(n))
+		b.ResetTimer()
+
+		for i := 0; i < b.N; i++ {
+			c, err := aes.NewCipher(TestVectors[0].Key)
+			if err != nil {
+				b.Fatal(err)
+			}
+
+			DecryptBlocks(c, TestVectors[0].IV, dst, src)
+		}
+	}
+}

encrypt.go

@@ -46,3 +46,14 @@ func (i *igeEncrypter) CryptBlocks(dst, src []byte) {
 		m = src[o : o+b]
 	}
 }
+
+// EncryptBlocks is a simple shorthand for IGE encrypting.
+// Note: unlike NewIGEEncrypter, EncryptBlocks does NOT COPY iv.
+// So you must not modify passed iv.
+func EncryptBlocks(b cipher.Block, iv, dst, src []byte) {
+	if err := checkIV(b, iv); err != nil {
+		panic(err.Error())
+	}
+	enc := igeEncrypter{block: b, iv: iv}
+	enc.CryptBlocks(dst, src)
+}

encrypt_test.go

@@ -3,6 +3,7 @@ package ige
 import (
 	"bytes"
 	"crypto/aes"
+	"fmt"
 	"testing"
 )
 
@@ -52,6 +53,23 @@ func TestEncrypterCryptBlocks(t *testing.T) {
 	}
 }
 
+func TestEncryptBlocks(t *testing.T) {
+	for a, v := range TestVectors {
+		out := make([]byte, len(v.Ciphertext))
+
+		c, err := aes.NewCipher(v.Key)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		EncryptBlocks(c, v.IV, out, v.Plaintext)
+
+		if !bytes.Equal(out, v.Ciphertext) {
+			t.Fatalf("test vector %d has wrong ciphertext\n", a+1)
+		}
+	}
+}
+
 func TestEncryptCryptBlocksPanicSrc(t *testing.T) {
 	c, err := aes.NewCipher(make([]byte, 16))
 	if err != nil {
@@ -83,3 +101,38 @@ func TestEncryptCryptBlocksPanicDst(t *testing.T) {
 	i := NewIGEEncrypter(c, make([]byte, 32))
 	i.CryptBlocks(make([]byte, 1), make([]byte, 16))
 }
+
+func BenchmarkEncryptBlocks(b *testing.B) {
+	for _, payload := range []int{
+		16,
+		128,
+		1024,
+		8192,
+		64 * 1024,
+		512 * 1024,
+	} {
+		b.Run(fmt.Sprintf("%d", payload), benchEncrypt(payload))
+	}
+}
+
+func benchEncrypt(n int) func(b *testing.B) {
+	return func(b *testing.B) {
+		b.Helper()
+
+		src := make([]byte, n)
+		dst := make([]byte, n)
+
+		b.ReportAllocs()
+		b.SetBytes(int64(n))
+		b.ResetTimer()
+
+		for i := 0; i < b.N; i++ {
+			c, err := aes.NewCipher(TestVectors[0].Key)
+			if err != nil {
+				b.Fatal(err)
+			}
+
+			EncryptBlocks(c, TestVectors[0].IV, dst, src)
+		}
+	}
+}

go.sum

@@ -1,3 +1,2 @@
-github.com/gotd/xor v0.1.0 h1:kg9XdEeTpbZbvsyjQq2l+UbgvZanJFRSazrI06+qXG0=
-github.com/gotd/xor v0.1.0/go.mod h1:ZTmdgqf6SOHder8/MFp9CNkXIadzID5lIiaZxRZICH0=
+github.com/gotd/xor v0.1.1 h1:LSPEeuf7noTo4fi4PrEsAaWXOSwjsY2e+IINPiR+c7s=
 github.com/gotd/xor v0.1.1/go.mod h1:ZTmdgqf6SOHder8/MFp9CNkXIadzID5lIiaZxRZICH0=