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|
package dsse
import (
"context"
"crypto"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/sha256"
"encoding/base64"
"errors"
"fmt"
"math/big"
"testing"
"github.com/codahale/rfc6979"
"github.com/stretchr/testify/assert"
)
var errLength = errors.New("invalid length")
func TestPAE(t *testing.T) {
t.Run("Empty", func(t *testing.T) {
var want = []byte("DSSEv1 0 0 ")
got := PAE("", []byte{})
assert.Equal(t, want, got, "Wrong encoding")
})
t.Run("Hello world", func(t *testing.T) {
var want = []byte("DSSEv1 29 http://example.com/HelloWorld 11 hello world")
got := PAE("http://example.com/HelloWorld", []byte("hello world"))
assert.Equal(t, want, got, "Wrong encoding")
})
t.Run("Unicode-only", func(t *testing.T) {
var want = []byte("DSSEv1 29 http://example.com/HelloWorld 3 ಠ")
got := PAE("http://example.com/HelloWorld", []byte("ಠ"))
assert.Equal(t, want, got, "Wrong encoding")
})
}
type nilSignerVerifier int
func (n nilSignerVerifier) Sign(ctx context.Context, data []byte) ([]byte, error) {
return data, nil
}
func (n nilSignerVerifier) Verify(ctx context.Context, data, sig []byte) error {
if len(data) != len(sig) {
return errLength
}
for i := range data {
if data[i] != sig[i] {
return errVerify
}
}
return nil
}
func (n nilSignerVerifier) KeyID() (string, error) {
return "nil", nil
}
func (n nilSignerVerifier) Public() crypto.PublicKey {
return "nil-public"
}
type nullSignerVerifier int
func (n nullSignerVerifier) Sign(ctx context.Context, data []byte) ([]byte, error) {
return data, nil
}
func (n nullSignerVerifier) Verify(ctx context.Context, data, sig []byte) error {
if len(data) != len(sig) {
return errLength
}
for i := range data {
if data[i] != sig[i] {
return errVerify
}
}
return nil
}
func (n nullSignerVerifier) KeyID() (string, error) {
return "null", nil
}
func (n nullSignerVerifier) Public() crypto.PublicKey {
return "null-public"
}
type errsigner int
func (n errsigner) Sign(ctx context.Context, data []byte) ([]byte, error) {
return nil, fmt.Errorf("signing error")
}
func (n errsigner) Verify(ctx context.Context, data, sig []byte) error {
return errVerify
}
func (n errsigner) KeyID() (string, error) {
return "err", nil
}
func (n errsigner) Public() crypto.PublicKey {
return "err-public"
}
type errSignerVerifier int
var errVerify = fmt.Errorf("accepted signatures do not match threshold, Found: 0, Expected 1")
var errThreshold = fmt.Errorf("invalid threshold")
func (n errSignerVerifier) Sign(ctx context.Context, data []byte) ([]byte, error) {
return data, nil
}
func (n errSignerVerifier) Verify(ctx context.Context, data, sig []byte) error {
return errVerify
}
func (n errSignerVerifier) KeyID() (string, error) {
return "err", nil
}
func (n errSignerVerifier) Public() crypto.PublicKey {
return "err-public"
}
type badverifier int
func (n badverifier) Sign(ctx context.Context, data []byte) ([]byte, error) {
return append(data, byte(0)), nil
}
func (n badverifier) Verify(ctx context.Context, data, sig []byte) error {
if len(data) != len(sig) {
return errLength
}
for i := range data {
if data[i] != sig[i] {
return errVerify
}
}
return nil
}
func (n badverifier) KeyID() (string, error) {
return "bad", nil
}
func (n badverifier) Public() crypto.PublicKey {
return "bad-public"
}
func TestNoSigners(t *testing.T) {
t.Run("nil slice", func(t *testing.T) {
signer, err := NewEnvelopeSigner(nil)
assert.Nil(t, signer, "unexpected signer")
assert.NotNil(t, err, "error expected")
assert.Equal(t, ErrNoSigners, err, "wrong error")
})
t.Run("empty slice", func(t *testing.T) {
signer, err := NewEnvelopeSigner([]Signer{}...)
assert.Nil(t, signer, "unexpected signer")
assert.NotNil(t, err, "error expected")
assert.Equal(t, ErrNoSigners, err, "wrong error")
})
}
func TestNilSign(t *testing.T) {
var keyID = "nil"
var payloadType = "http://example.com/HelloWorld"
var payload = []byte("hello world")
pae := PAE(payloadType, payload)
want := Envelope{
Payload: base64.StdEncoding.EncodeToString([]byte(payload)),
PayloadType: payloadType,
Signatures: []Signature{
{
KeyID: keyID,
Sig: base64.StdEncoding.EncodeToString(pae),
},
},
}
var ns nilSignerVerifier
signer, err := NewEnvelopeSigner(ns)
assert.Nil(t, err, "unexpected error")
got, err := signer.SignPayload(context.TODO(), payloadType, []byte(payload))
assert.Nil(t, err, "sign failed")
assert.Equal(t, &want, got, "bad signature")
}
func TestSignError(t *testing.T) {
var es errsigner
signer, err := NewEnvelopeSigner(es)
assert.Nil(t, err, "unexpected error")
got, err := signer.SignPayload(context.TODO(), "t", []byte("d"))
assert.Nil(t, got, "expected nil")
assert.NotNil(t, err, "error expected")
assert.Equal(t, "signing error", err.Error(), "wrong error")
}
func newEcdsaKey() *ecdsa.PrivateKey {
var x big.Int
var y big.Int
var d big.Int
_, ok := x.SetString("46950820868899156662930047687818585632848591499744589407958293238635476079160", 10)
if !ok {
return nil
}
_, ok = y.SetString("5640078356564379163099075877009565129882514886557779369047442380624545832820", 10)
if !ok {
return nil
}
_, ok = d.SetString("97358161215184420915383655311931858321456579547487070936769975997791359926199", 10)
if !ok {
return nil
}
var private = ecdsa.PrivateKey{
PublicKey: ecdsa.PublicKey{
Curve: elliptic.P256(),
X: &x,
Y: &y,
},
D: &d,
}
return &private
}
type ecdsaSignerVerifier struct {
keyID string
key *ecdsa.PrivateKey
rLen int
verified bool
}
func (es *ecdsaSignerVerifier) Sign(ctx context.Context, data []byte) ([]byte, error) {
// Data is complete message, hash it and sign the digest
digest := sha256.Sum256(data)
r, s, err := rfc6979.SignECDSA(es.key, digest[:], sha256.New)
if err != nil {
return nil, err
}
rb := r.Bytes()
sb := s.Bytes()
es.rLen = len(rb)
rawSig := append(rb, sb...)
return rawSig, nil
}
func (es *ecdsaSignerVerifier) Verify(ctx context.Context, data, sig []byte) error {
var r big.Int
var s big.Int
digest := sha256.Sum256(data)
// Signature here is the raw bytes of r and s concatenated
rb := sig[:es.rLen]
sb := sig[es.rLen:]
r.SetBytes(rb)
s.SetBytes(sb)
ok := ecdsa.Verify(&es.key.PublicKey, digest[:], &r, &s)
es.verified = ok
if ok {
return nil
}
return errVerify
}
func (es *ecdsaSignerVerifier) KeyID() (string, error) {
return es.keyID, nil
}
func (es *ecdsaSignerVerifier) Public() crypto.PublicKey {
return es.key.Public()
}
// Test against the example in the protocol specification:
// https://github.com/secure-systems-lab/dsse/blob/master/protocol.md
func TestEcdsaSign(t *testing.T) {
var keyID = "test key 123"
var payloadType = "http://example.com/HelloWorld"
var payload = "hello world"
var ecdsa = &ecdsaSignerVerifier{
keyID: keyID,
key: newEcdsaKey(),
}
var want = Envelope{
Payload: "aGVsbG8gd29ybGQ=",
PayloadType: payloadType,
Signatures: []Signature{
{
KeyID: keyID,
Sig: "A3JqsQGtVsJ2O2xqrI5IcnXip5GToJ3F+FnZ+O88SjtR6rDAajabZKciJTfUiHqJPcIAriEGAHTVeCUjW2JIZA==",
},
},
}
signer, err := NewEnvelopeSigner(ecdsa)
assert.Nil(t, err, "unexpected error")
env, err := signer.SignPayload(context.TODO(), payloadType, []byte(payload))
assert.Nil(t, err, "unexpected error")
assert.Equal(t, &want, env, "Wrong envelope generated")
// Now verify
verifier, err := NewEnvelopeVerifier(ecdsa)
assert.Nil(t, err, "unexpected error")
acceptedKeys, err := verifier.Verify(context.TODO(), env)
assert.Nil(t, err, "unexpected error")
assert.True(t, ecdsa.verified, "verify was not called")
assert.Len(t, acceptedKeys, 1, "unexpected keys")
assert.Equal(t, acceptedKeys[0].KeyID, keyID, "unexpected keyid")
}
func TestDecodeB64Payload(t *testing.T) {
var want = make([]byte, 256)
for i := range want {
want[i] = byte(i)
}
var b64Url = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4OTo7PD0+P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3BxcnN0dXZ3eHl6e3x9fn+AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmqq6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w=="
var b64Std = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4OTo7PD0-P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3BxcnN0dXZ3eHl6e3x9fn-AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmqq6ytrq-wsbKztLW2t7i5uru8vb6_wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t_g4eLj5OXm5-jp6uvs7e7v8PHy8_T19vf4-fr7_P3-_w=="
var b64UrlErr = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4OTo7PD0+P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3BxcnN0dXZ3eHl6e3x9fn+AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmqq6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w"
var b64StdErr = "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4OTo7PD0-P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3BxcnN0dXZ3eHl6e3x9fn-AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmqq6ytrq-wsbKztLW2t7i5uru8vb6_wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t_g4eLj5OXm5-jp6uvs7e7v8PHy8_T19vf4-fr7_P3-_w"
t.Run("Standard encoding", func(t *testing.T) {
env := &Envelope{
Payload: b64Std,
}
got, err := env.DecodeB64Payload()
assert.Nil(t, err, "unexpected error")
assert.Equal(t, want, got, "wrong data")
})
t.Run("URL encoding", func(t *testing.T) {
env := &Envelope{
Payload: b64Url,
}
got, err := env.DecodeB64Payload()
assert.Nil(t, err, "unexpected error")
assert.Equal(t, want, got, "wrong data")
})
t.Run("Standard encoding - error", func(t *testing.T) {
env := &Envelope{
Payload: b64StdErr,
}
got, err := env.DecodeB64Payload()
assert.NotNil(t, err, "expected error")
assert.Nil(t, got, "wrong data")
})
t.Run("URL encoding - error", func(t *testing.T) {
env := &Envelope{
Payload: b64UrlErr,
}
got, err := env.DecodeB64Payload()
assert.NotNil(t, err, "expected error")
assert.Nil(t, got, "wrong data")
})
}
|
