src/crypto/rsa/pkcs1v15_test.go - go - Git at Google

 // Copyright 2009 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 package rsa

 import (
 	"bytes"
 	"crypto"
 	"crypto/rand"
 	"crypto/sha1"
 	"crypto/sha256"
 	"encoding/base64"
 	"encoding/hex"
 	"io"
 	"math/big"
 	"testing"
 	"testing/quick"
 )

 func decodeBase64(in string) []byte {
 	out := make([]byte, base64.StdEncoding.DecodedLen(len(in)))
 	n, err := base64.StdEncoding.Decode(out, []byte(in))
 	if err != nil {
 		return nil
 	}
 	return out[0:n]
 }

 type DecryptPKCS1v15Test struct {
 	in, out string
 }

 // These test vectors were generated with `openssl rsautl -pkcs -encrypt`
 var decryptPKCS1v15Tests = []DecryptPKCS1v15Test{
 	{
 		"gIcUIoVkD6ATMBk/u/nlCZCCWRKdkfjCgFdo35VpRXLduiKXhNz1XupLLzTXAybEq15juc+EgY5o0DHv/nt3yg==",
 		"x",
 	},
 	{
 		"Y7TOCSqofGhkRb+jaVRLzK8xw2cSo1IVES19utzv6hwvx+M8kFsoWQm5DzBeJCZTCVDPkTpavUuEbgp8hnUGDw==",
 		"testing.",
 	},
 	{
 		"arReP9DJtEVyV2Dg3dDp4c/PSk1O6lxkoJ8HcFupoRorBZG+7+1fDAwT1olNddFnQMjmkb8vxwmNMoTAT/BFjQ==",
 		"testing.\n",
 	},
 	{
 		"WtaBXIoGC54+vH0NH0CHHE+dRDOsMc/6BrfFu2lEqcKL9+uDuWaf+Xj9mrbQCjjZcpQuX733zyok/jsnqe/Ftw==",
 		"01234567890123456789012345678901234567890123456789012",
 	},
 }

 func TestDecryptPKCS1v15(t *testing.T) {
 	decryptionFuncs := []func([]byte) ([]byte, error){
 		func(ciphertext []byte) (plaintext []byte, err error) {
 			return DecryptPKCS1v15(nil, rsaPrivateKey, ciphertext)
 		},
 		func(ciphertext []byte) (plaintext []byte, err error) {
 			return rsaPrivateKey.Decrypt(nil, ciphertext, nil)
 		},
 	}

 	for _, decryptFunc := range decryptionFuncs {
 		for i, test := range decryptPKCS1v15Tests {
 			out, err := decryptFunc(decodeBase64(test.in))
 			if err != nil {
 				t.Errorf("#%d error decrypting", i)
 			}
 			want := []byte(test.out)
 			if !bytes.Equal(out, want) {
 				t.Errorf("#%d got:%#v want:%#v", i, out, want)
 			}
 		}
 	}
 }

 func TestEncryptPKCS1v15(t *testing.T) {
 	random := rand.Reader
 	k := (rsaPrivateKey.N.BitLen() + 7) / 8

 	tryEncryptDecrypt := func(in []byte, blind bool) bool {
 		if len(in) > k-11 {
 			in = in[0 : k-11]
 		}

 		ciphertext, err := EncryptPKCS1v15(random, &rsaPrivateKey.PublicKey, in)
 		if err != nil {
 			t.Errorf("error encrypting: %s", err)
 			return false
 		}

 		var rand io.Reader
 		if !blind {
 			rand = nil
 		} else {
 			rand = random
 		}
 		plaintext, err := DecryptPKCS1v15(rand, rsaPrivateKey, ciphertext)
 		if err != nil {
 			t.Errorf("error decrypting: %s", err)
 			return false
 		}

 		if !bytes.Equal(plaintext, in) {
 			t.Errorf("output mismatch: %#v %#v", plaintext, in)
 			return false
 		}
 		return true
 	}

 	config := new(quick.Config)
 	if testing.Short() {
 		config.MaxCount = 10
 	}
 	quick.Check(tryEncryptDecrypt, config)
 }

 // These test vectors were generated with `openssl rsautl -pkcs -encrypt`
 var decryptPKCS1v15SessionKeyTests = []DecryptPKCS1v15Test{
 	{
 		"e6ukkae6Gykq0fKzYwULpZehX+UPXYzMoB5mHQUDEiclRbOTqas4Y0E6nwns1BBpdvEJcilhl5zsox/6DtGsYg==",
 		"1234",
 	},
 	{
 		"Dtis4uk/q/LQGGqGk97P59K03hkCIVFMEFZRgVWOAAhxgYpCRG0MX2adptt92l67IqMki6iVQyyt0TtX3IdtEw==",
 		"FAIL",
 	},
 	{
 		"LIyFyCYCptPxrvTxpol8F3M7ZivlMsf53zs0vHRAv+rDIh2YsHS69ePMoPMe3TkOMZ3NupiL3takPxIs1sK+dw==",
 		"abcd",
 	},
 	{
 		"bafnobel46bKy76JzqU/RIVOH0uAYvzUtauKmIidKgM0sMlvobYVAVQPeUQ/oTGjbIZ1v/6Gyi5AO4DtHruGdw==",
 		"FAIL",
 	},
 }

 func TestEncryptPKCS1v15SessionKey(t *testing.T) {
 	for i, test := range decryptPKCS1v15SessionKeyTests {
 		key := []byte("FAIL")
 		err := DecryptPKCS1v15SessionKey(nil, rsaPrivateKey, decodeBase64(test.in), key)
 		if err != nil {
 			t.Errorf("#%d error decrypting", i)
 		}
 		want := []byte(test.out)
 		if !bytes.Equal(key, want) {
 			t.Errorf("#%d got:%#v want:%#v", i, key, want)
 		}
 	}
 }

 func TestEncryptPKCS1v15DecrypterSessionKey(t *testing.T) {
 	for i, test := range decryptPKCS1v15SessionKeyTests {
 		plaintext, err := rsaPrivateKey.Decrypt(rand.Reader, decodeBase64(test.in), &PKCS1v15DecryptOptions{SessionKeyLen: 4})
 		if err != nil {
 			t.Fatalf("#%d: error decrypting: %s", i, err)
 		}
 		if len(plaintext) != 4 {
 			t.Fatalf("#%d: incorrect length plaintext: got %d, want 4", i, len(plaintext))
 		}

 		if test.out != "FAIL" && !bytes.Equal(plaintext, []byte(test.out)) {
 			t.Errorf("#%d: incorrect plaintext: got %x, want %x", i, plaintext, test.out)
 		}
 	}
 }

 func TestNonZeroRandomBytes(t *testing.T) {
 	random := rand.Reader

 	b := make([]byte, 512)
 	err := nonZeroRandomBytes(b, random)
 	if err != nil {
 		t.Errorf("returned error: %s", err)
 	}
 	for _, b := range b {
 		if b == 0 {
 			t.Errorf("Zero octet found")
 			return
 		}
 	}
 }

 type signPKCS1v15Test struct {
 	in, out string
 }

 // These vectors have been tested with
 //
 //	`openssl rsautl -verify -inkey pk -in signature | hexdump -C`
 var signPKCS1v15Tests = []signPKCS1v15Test{
 	{"Test.\n", "a4f3fa6ea93bcdd0c57be020c1193ecbfd6f200a3d95c409769b029578fa0e336ad9a347600e40d3ae823b8c7e6bad88cc07c1d54c3a1523cbbb6d58efc362ae"},
 }

 func TestSignPKCS1v15(t *testing.T) {
 	for i, test := range signPKCS1v15Tests {
 		h := sha1.New()
 		h.Write([]byte(test.in))
 		digest := h.Sum(nil)

 		s, err := SignPKCS1v15(nil, rsaPrivateKey, crypto.SHA1, digest)
 		if err != nil {
 			t.Errorf("#%d %s", i, err)
 		}

 		expected, _ := hex.DecodeString(test.out)
 		if !bytes.Equal(s, expected) {
 			t.Errorf("#%d got: %x want: %x", i, s, expected)
 		}
 	}
 }

 func TestVerifyPKCS1v15(t *testing.T) {
 	for i, test := range signPKCS1v15Tests {
 		h := sha1.New()
 		h.Write([]byte(test.in))
 		digest := h.Sum(nil)

 		sig, _ := hex.DecodeString(test.out)

 		err := VerifyPKCS1v15(&rsaPrivateKey.PublicKey, crypto.SHA1, digest, sig)
 		if err != nil {
 			t.Errorf("#%d %s", i, err)
 		}
 	}
 }

 func TestOverlongMessagePKCS1v15(t *testing.T) {
 	ciphertext := decodeBase64("fjOVdirUzFoLlukv80dBllMLjXythIf22feqPrNo0YoIjzyzyoMFiLjAc/Y4krkeZ11XFThIrEvw\nkRiZcCq5ng==")
 	_, err := DecryptPKCS1v15(nil, rsaPrivateKey, ciphertext)
 	if err == nil {
 		t.Error("RSA decrypted a message that was too long.")
 	}
 }

 func TestUnpaddedSignature(t *testing.T) {
 	msg := []byte("Thu Dec 19 18:06:16 EST 2013\n")
 	// This base64 value was generated with:
 	// % echo Thu Dec 19 18:06:16 EST 2013 > /tmp/msg
 	// % openssl rsautl -sign -inkey key -out /tmp/sig -in /tmp/msg
 	//
 	// Where "key" contains the RSA private key given at the bottom of this
 	// file.
 	expectedSig := decodeBase64("pX4DR8azytjdQ1rtUiC040FjkepuQut5q2ZFX1pTjBrOVKNjgsCDyiJDGZTCNoh9qpXYbhl7iEym30BWWwuiZg==")

 	sig, err := SignPKCS1v15(nil, rsaPrivateKey, crypto.Hash(0), msg)
 	if err != nil {
 		t.Fatalf("SignPKCS1v15 failed: %s", err)
 	}
 	if !bytes.Equal(sig, expectedSig) {
 		t.Fatalf("signature is not expected value: got %x, want %x", sig, expectedSig)
 	}
 	if err := VerifyPKCS1v15(&rsaPrivateKey.PublicKey, crypto.Hash(0), msg, sig); err != nil {
 		t.Fatalf("signature failed to verify: %s", err)
 	}
 }

 func TestShortSessionKey(t *testing.T) {
 	// This tests that attempting to decrypt a session key where the
 	// ciphertext is too small doesn't run outside the array bounds.
 	ciphertext, err := EncryptPKCS1v15(rand.Reader, &rsaPrivateKey.PublicKey, []byte{1})
 	if err != nil {
 		t.Fatalf("Failed to encrypt short message: %s", err)
 	}

 	var key [32]byte
 	if err := DecryptPKCS1v15SessionKey(nil, rsaPrivateKey, ciphertext, key[:]); err != nil {
 		t.Fatalf("Failed to decrypt short message: %s", err)
 	}

 	for _, v := range key {
 		if v != 0 {
 			t.Fatal("key was modified when ciphertext was invalid")
 		}
 	}
 }

 // In order to generate new test vectors you'll need the PEM form of this key (and s/TESTING/PRIVATE/):
 // -----BEGIN RSA TESTING KEY-----
 // MIIBOgIBAAJBALKZD0nEffqM1ACuak0bijtqE2QrI/KLADv7l3kK3ppMyCuLKoF0
 // fd7Ai2KW5ToIwzFofvJcS/STa6HA5gQenRUCAwEAAQJBAIq9amn00aS0h/CrjXqu
 // /ThglAXJmZhOMPVn4eiu7/ROixi9sex436MaVeMqSNf7Ex9a8fRNfWss7Sqd9eWu
 // RTUCIQDasvGASLqmjeffBNLTXV2A5g4t+kLVCpsEIZAycV5GswIhANEPLmax0ME/
 // EO+ZJ79TJKN5yiGBRsv5yvx5UiHxajEXAiAhAol5N4EUyq6I9w1rYdhPMGpLfk7A
 // IU2snfRJ6Nq2CQIgFrPsWRCkV+gOYcajD17rEqmuLrdIRexpg8N1DOSXoJ8CIGlS
 // tAboUGBxTDq3ZroNism3DaMIbKPyYrAqhKov1h5V
 // -----END RSA TESTING KEY-----

 var rsaPrivateKey = &PrivateKey{
 	PublicKey: PublicKey{
 		N: fromBase10("9353930466774385905609975137998169297361893554149986716853295022578535724979677252958524466350471210367835187480748268864277464700638583474144061408845077"),
 		E: 65537,
 	},
 	D: fromBase10("7266398431328116344057699379749222532279343923819063639497049039389899328538543087657733766554155839834519529439851673014800261285757759040931985506583861"),
 	Primes: []*big.Int{
 		fromBase10("98920366548084643601728869055592650835572950932266967461790948584315647051443"),
 		fromBase10("94560208308847015747498523884063394671606671904944666360068158221458669711639"),
 	},
 }

 func TestShortPKCS1v15Signature(t *testing.T) {
 	pub := &PublicKey{
 		E: 65537,
 		N: fromBase10("8272693557323587081220342447407965471608219912416565371060697606400726784709760494166080686904546560026343451112103559482851304715739629410219358933351333"),
 	}
 	sig, err := hex.DecodeString("193a310d0dcf64094c6e3a00c8219b80ded70535473acff72c08e1222974bb24a93a535b1dc4c59fc0e65775df7ba2007dd20e9193f4c4025a18a7070aee93")
 	if err != nil {
 		t.Fatalf("failed to decode signature: %s", err)
 	}

 	h := sha256.Sum256([]byte("hello"))
 	err = VerifyPKCS1v15(pub, crypto.SHA256, h[:], sig)
 	if err == nil {
 		t.Fatal("VerifyPKCS1v15 accepted a truncated signature")
 	}
 }
	// Copyright 2009 The Go Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	package rsa

	import (
	"bytes"
	"crypto"
	"crypto/rand"
	"crypto/sha1"
	"crypto/sha256"
	"encoding/base64"
	"encoding/hex"
	"io"
	"math/big"
	"testing"
	"testing/quick"
	)

	func decodeBase64(in string) []byte {
	out := make([]byte, base64.StdEncoding.DecodedLen(len(in)))
	n, err := base64.StdEncoding.Decode(out, []byte(in))
	if err != nil {
	return nil
	}
	return out[0:n]
	}

	type DecryptPKCS1v15Test struct {
	in, out string
	}

	// These test vectors were generated with `openssl rsautl -pkcs -encrypt`
	var decryptPKCS1v15Tests = []DecryptPKCS1v15Test{
	{
	"gIcUIoVkD6ATMBk/u/nlCZCCWRKdkfjCgFdo35VpRXLduiKXhNz1XupLLzTXAybEq15juc+EgY5o0DHv/nt3yg==",
	"x",
	},
	{
	"Y7TOCSqofGhkRb+jaVRLzK8xw2cSo1IVES19utzv6hwvx+M8kFsoWQm5DzBeJCZTCVDPkTpavUuEbgp8hnUGDw==",
	"testing.",
	},
	{
	"arReP9DJtEVyV2Dg3dDp4c/PSk1O6lxkoJ8HcFupoRorBZG+7+1fDAwT1olNddFnQMjmkb8vxwmNMoTAT/BFjQ==",
	"testing.\n",
	},
	{
	"WtaBXIoGC54+vH0NH0CHHE+dRDOsMc/6BrfFu2lEqcKL9+uDuWaf+Xj9mrbQCjjZcpQuX733zyok/jsnqe/Ftw==",
	"01234567890123456789012345678901234567890123456789012",
	},
	}

	func TestDecryptPKCS1v15(t *testing.T) {
	decryptionFuncs := []func([]byte) ([]byte, error){
	func(ciphertext []byte) (plaintext []byte, err error) {
	return DecryptPKCS1v15(nil, rsaPrivateKey, ciphertext)
	},
	func(ciphertext []byte) (plaintext []byte, err error) {
	return rsaPrivateKey.Decrypt(nil, ciphertext, nil)
	},
	}

	for _, decryptFunc := range decryptionFuncs {
	for i, test := range decryptPKCS1v15Tests {
	out, err := decryptFunc(decodeBase64(test.in))
	if err != nil {
	t.Errorf("#%d error decrypting", i)
	}
	want := []byte(test.out)
	if !bytes.Equal(out, want) {
	t.Errorf("#%d got:%#v want:%#v", i, out, want)
	}
	}
	}
	}

	func TestEncryptPKCS1v15(t *testing.T) {
	random := rand.Reader
	k := (rsaPrivateKey.N.BitLen() + 7) / 8

	tryEncryptDecrypt := func(in []byte, blind bool) bool {
	if len(in) > k-11 {
	in = in[0 : k-11]
	}

	ciphertext, err := EncryptPKCS1v15(random, &rsaPrivateKey.PublicKey, in)
	if err != nil {
	t.Errorf("error encrypting: %s", err)
	return false
	}

	var rand io.Reader
	if !blind {
	rand = nil
	} else {
	rand = random
	}
	plaintext, err := DecryptPKCS1v15(rand, rsaPrivateKey, ciphertext)
	if err != nil {
	t.Errorf("error decrypting: %s", err)
	return false
	}

	if !bytes.Equal(plaintext, in) {
	t.Errorf("output mismatch: %#v %#v", plaintext, in)
	return false
	}
	return true
	}

	config := new(quick.Config)
	if testing.Short() {
	config.MaxCount = 10
	}
	quick.Check(tryEncryptDecrypt, config)
	}

	// These test vectors were generated with `openssl rsautl -pkcs -encrypt`
	var decryptPKCS1v15SessionKeyTests = []DecryptPKCS1v15Test{
	{
	"e6ukkae6Gykq0fKzYwULpZehX+UPXYzMoB5mHQUDEiclRbOTqas4Y0E6nwns1BBpdvEJcilhl5zsox/6DtGsYg==",
	"1234",
	},
	{
	"Dtis4uk/q/LQGGqGk97P59K03hkCIVFMEFZRgVWOAAhxgYpCRG0MX2adptt92l67IqMki6iVQyyt0TtX3IdtEw==",
	"FAIL",
	},
	{
	"LIyFyCYCptPxrvTxpol8F3M7ZivlMsf53zs0vHRAv+rDIh2YsHS69ePMoPMe3TkOMZ3NupiL3takPxIs1sK+dw==",
	"abcd",
	},
	{
	"bafnobel46bKy76JzqU/RIVOH0uAYvzUtauKmIidKgM0sMlvobYVAVQPeUQ/oTGjbIZ1v/6Gyi5AO4DtHruGdw==",
	"FAIL",
	},
	}

	func TestEncryptPKCS1v15SessionKey(t *testing.T) {
	for i, test := range decryptPKCS1v15SessionKeyTests {
	key := []byte("FAIL")
	err := DecryptPKCS1v15SessionKey(nil, rsaPrivateKey, decodeBase64(test.in), key)
	if err != nil {
	t.Errorf("#%d error decrypting", i)
	}
	want := []byte(test.out)
	if !bytes.Equal(key, want) {
	t.Errorf("#%d got:%#v want:%#v", i, key, want)
	}
	}
	}

	func TestEncryptPKCS1v15DecrypterSessionKey(t *testing.T) {
	for i, test := range decryptPKCS1v15SessionKeyTests {
	plaintext, err := rsaPrivateKey.Decrypt(rand.Reader, decodeBase64(test.in), &PKCS1v15DecryptOptions{SessionKeyLen: 4})
	if err != nil {
	t.Fatalf("#%d: error decrypting: %s", i, err)
	}
	if len(plaintext) != 4 {
	t.Fatalf("#%d: incorrect length plaintext: got %d, want 4", i, len(plaintext))
	}

	if test.out != "FAIL" && !bytes.Equal(plaintext, []byte(test.out)) {
	t.Errorf("#%d: incorrect plaintext: got %x, want %x", i, plaintext, test.out)
	}
	}
	}

	func TestNonZeroRandomBytes(t *testing.T) {
	random := rand.Reader

	b := make([]byte, 512)
	err := nonZeroRandomBytes(b, random)
	if err != nil {
	t.Errorf("returned error: %s", err)
	}
	for _, b := range b {
	if b == 0 {
	t.Errorf("Zero octet found")
	return
	}
	}
	}

	type signPKCS1v15Test struct {
	in, out string
	}

	// These vectors have been tested with
	//
	// `openssl rsautl -verify -inkey pk -in signature \| hexdump -C`
	var signPKCS1v15Tests = []signPKCS1v15Test{
	{"Test.\n", "a4f3fa6ea93bcdd0c57be020c1193ecbfd6f200a3d95c409769b029578fa0e336ad9a347600e40d3ae823b8c7e6bad88cc07c1d54c3a1523cbbb6d58efc362ae"},
	}

	func TestSignPKCS1v15(t *testing.T) {
	for i, test := range signPKCS1v15Tests {
	h := sha1.New()
	h.Write([]byte(test.in))
	digest := h.Sum(nil)

	s, err := SignPKCS1v15(nil, rsaPrivateKey, crypto.SHA1, digest)
	if err != nil {
	t.Errorf("#%d %s", i, err)
	}

	expected, _ := hex.DecodeString(test.out)
	if !bytes.Equal(s, expected) {
	t.Errorf("#%d got: %x want: %x", i, s, expected)
	}
	}
	}

	func TestVerifyPKCS1v15(t *testing.T) {
	for i, test := range signPKCS1v15Tests {
	h := sha1.New()
	h.Write([]byte(test.in))
	digest := h.Sum(nil)

	sig, _ := hex.DecodeString(test.out)

	err := VerifyPKCS1v15(&rsaPrivateKey.PublicKey, crypto.SHA1, digest, sig)
	if err != nil {
	t.Errorf("#%d %s", i, err)
	}
	}
	}

	func TestOverlongMessagePKCS1v15(t *testing.T) {
	ciphertext := decodeBase64("fjOVdirUzFoLlukv80dBllMLjXythIf22feqPrNo0YoIjzyzyoMFiLjAc/Y4krkeZ11XFThIrEvw\nkRiZcCq5ng==")
	_, err := DecryptPKCS1v15(nil, rsaPrivateKey, ciphertext)
	if err == nil {
	t.Error("RSA decrypted a message that was too long.")
	}
	}

	func TestUnpaddedSignature(t *testing.T) {
	msg := []byte("Thu Dec 19 18:06:16 EST 2013\n")
	// This base64 value was generated with:
	// % echo Thu Dec 19 18:06:16 EST 2013 > /tmp/msg
	// % openssl rsautl -sign -inkey key -out /tmp/sig -in /tmp/msg
	//
	// Where "key" contains the RSA private key given at the bottom of this
	// file.
	expectedSig := decodeBase64("pX4DR8azytjdQ1rtUiC040FjkepuQut5q2ZFX1pTjBrOVKNjgsCDyiJDGZTCNoh9qpXYbhl7iEym30BWWwuiZg==")

	sig, err := SignPKCS1v15(nil, rsaPrivateKey, crypto.Hash(0), msg)
	if err != nil {
	t.Fatalf("SignPKCS1v15 failed: %s", err)
	}
	if !bytes.Equal(sig, expectedSig) {
	t.Fatalf("signature is not expected value: got %x, want %x", sig, expectedSig)
	}
	if err := VerifyPKCS1v15(&rsaPrivateKey.PublicKey, crypto.Hash(0), msg, sig); err != nil {
	t.Fatalf("signature failed to verify: %s", err)
	}
	}

	func TestShortSessionKey(t *testing.T) {
	// This tests that attempting to decrypt a session key where the
	// ciphertext is too small doesn't run outside the array bounds.
	ciphertext, err := EncryptPKCS1v15(rand.Reader, &rsaPrivateKey.PublicKey, []byte{1})
	if err != nil {
	t.Fatalf("Failed to encrypt short message: %s", err)
	}

	var key [32]byte
	if err := DecryptPKCS1v15SessionKey(nil, rsaPrivateKey, ciphertext, key[:]); err != nil {
	t.Fatalf("Failed to decrypt short message: %s", err)
	}

	for _, v := range key {
	if v != 0 {
	t.Fatal("key was modified when ciphertext was invalid")
	}
	}
	}

	// In order to generate new test vectors you'll need the PEM form of this key (and s/TESTING/PRIVATE/):
	// -----BEGIN RSA TESTING KEY-----
	// MIIBOgIBAAJBALKZD0nEffqM1ACuak0bijtqE2QrI/KLADv7l3kK3ppMyCuLKoF0
	// fd7Ai2KW5ToIwzFofvJcS/STa6HA5gQenRUCAwEAAQJBAIq9amn00aS0h/CrjXqu
	// /ThglAXJmZhOMPVn4eiu7/ROixi9sex436MaVeMqSNf7Ex9a8fRNfWss7Sqd9eWu
	// RTUCIQDasvGASLqmjeffBNLTXV2A5g4t+kLVCpsEIZAycV5GswIhANEPLmax0ME/
	// EO+ZJ79TJKN5yiGBRsv5yvx5UiHxajEXAiAhAol5N4EUyq6I9w1rYdhPMGpLfk7A
	// IU2snfRJ6Nq2CQIgFrPsWRCkV+gOYcajD17rEqmuLrdIRexpg8N1DOSXoJ8CIGlS
	// tAboUGBxTDq3ZroNism3DaMIbKPyYrAqhKov1h5V
	// -----END RSA TESTING KEY-----

	var rsaPrivateKey = &PrivateKey{
	PublicKey: PublicKey{
	N: fromBase10("9353930466774385905609975137998169297361893554149986716853295022578535724979677252958524466350471210367835187480748268864277464700638583474144061408845077"),
	E: 65537,
	},
	D: fromBase10("7266398431328116344057699379749222532279343923819063639497049039389899328538543087657733766554155839834519529439851673014800261285757759040931985506583861"),
	Primes: []*big.Int{
	fromBase10("98920366548084643601728869055592650835572950932266967461790948584315647051443"),
	fromBase10("94560208308847015747498523884063394671606671904944666360068158221458669711639"),
	},
	}

	func TestShortPKCS1v15Signature(t *testing.T) {
	pub := &PublicKey{
	E: 65537,
	N: fromBase10("8272693557323587081220342447407965471608219912416565371060697606400726784709760494166080686904546560026343451112103559482851304715739629410219358933351333"),
	}
	sig, err := hex.DecodeString("193a310d0dcf64094c6e3a00c8219b80ded70535473acff72c08e1222974bb24a93a535b1dc4c59fc0e65775df7ba2007dd20e9193f4c4025a18a7070aee93")
	if err != nil {
	t.Fatalf("failed to decode signature: %s", err)
	}

	h := sha256.Sum256([]byte("hello"))
	err = VerifyPKCS1v15(pub, crypto.SHA256, h[:], sig)
	if err == nil {
	t.Fatal("VerifyPKCS1v15 accepted a truncated signature")
	}
	}