Cert interface (#1212)

cert/crypto_test.go

@@ -23,3 +23,90 @@ func TestNewArgon2Parameters(t *testing.T) {
 		Iterations:  1,
 	}, p)
 }
+
+func TestDecryptAndUnmarshalSigningPrivateKey(t *testing.T) {
+	passphrase := []byte("DO NOT USE THIS KEY")
+	privKey := []byte(`# A good key
+-----BEGIN NEBULA ED25519 ENCRYPTED PRIVATE KEY-----
+CjwKC0FFUy0yNTYtR0NNEi0IExCAgIABGAEgBCognnjujd67Vsv99p22wfAjQaDT
+oCMW1mdjkU3gACKNW4MSXOWR9Sts4C81yk1RUku2gvGKs3TB9LYoklLsIizSYOLl
++Vs//O1T0I1Xbml2XBAROsb/VSoDln/6LMqR4B6fn6B3GOsLBBqRI8daDl9lRMPB
+qrlJ69wer3ZUHFXA
+-----END NEBULA ED25519 ENCRYPTED PRIVATE KEY-----
+`)
+	shortKey := []byte(`# A key which, once decrypted, is too short
+-----BEGIN NEBULA ED25519 ENCRYPTED PRIVATE KEY-----
+CjwKC0FFUy0yNTYtR0NNEi0IExCAgIABGAEgBCoga5h8owMEBWRSMMJKzuUvWce7
+k0qlBkQmCxiuLh80MuASW70YcKt8jeEIS2axo2V6zAKA9TSMcCsJW1kDDXEtL/xe
+GLF5T7sDl5COp4LU3pGxpV+KoeQ/S3gQCAAcnaOtnJQX+aSDnbO3jCHyP7U9CHbs
+rQr3bdH3Oy/WiYU=
+-----END NEBULA ED25519 ENCRYPTED PRIVATE KEY-----
+`)
+	invalidBanner := []byte(`# Invalid banner (not encrypted)
+-----BEGIN NEBULA ED25519 PRIVATE KEY-----
+bWRp2CTVFhW9HD/qCd28ltDgK3w8VXSeaEYczDWos8sMUBqDb9jP3+NYwcS4lURG
+XgLvodMXZJuaFPssp+WwtA==
+-----END NEBULA ED25519 PRIVATE KEY-----
+`)
+	invalidPem := []byte(`# Not a valid PEM format
+-BEGIN NEBULA ED25519 ENCRYPTED PRIVATE KEY-----
+CjwKC0FFUy0yNTYtR0NNEi0IExCAgIABGAEgBCognnjujd67Vsv99p22wfAjQaDT
+oCMW1mdjkU3gACKNW4MSXOWR9Sts4C81yk1RUku2gvGKs3TB9LYoklLsIizSYOLl
++Vs//O1T0I1Xbml2XBAROsb/VSoDln/6LMqR4B6fn6B3GOsLBBqRI8daDl9lRMPB
+qrlJ69wer3ZUHFXA
+-END NEBULA ED25519 ENCRYPTED PRIVATE KEY-----
+`)
+
+	keyBundle := appendByteSlices(privKey, shortKey, invalidBanner, invalidPem)
+
+	// Success test case
+	curve, k, rest, err := DecryptAndUnmarshalSigningPrivateKey(passphrase, keyBundle)
+	assert.Nil(t, err)
+	assert.Equal(t, Curve_CURVE25519, curve)
+	assert.Len(t, k, 64)
+	assert.Equal(t, rest, appendByteSlices(shortKey, invalidBanner, invalidPem))
+
+	// Fail due to short key
+	curve, k, rest, err = DecryptAndUnmarshalSigningPrivateKey(passphrase, rest)
+	assert.EqualError(t, err, "key was not 64 bytes, is invalid ed25519 private key")
+	assert.Nil(t, k)
+	assert.Equal(t, rest, appendByteSlices(invalidBanner, invalidPem))
+
+	// Fail due to invalid banner
+	curve, k, rest, err = DecryptAndUnmarshalSigningPrivateKey(passphrase, rest)
+	assert.EqualError(t, err, "bytes did not contain a proper nebula encrypted Ed25519/ECDSA private key banner")
+	assert.Nil(t, k)
+	assert.Equal(t, rest, invalidPem)
+
+	// Fail due to ivalid PEM format, because
+	// it's missing the requisite pre-encapsulation boundary.
+	curve, k, rest, err = DecryptAndUnmarshalSigningPrivateKey(passphrase, rest)
+	assert.EqualError(t, err, "input did not contain a valid PEM encoded block")
+	assert.Nil(t, k)
+	assert.Equal(t, rest, invalidPem)
+
+	// Fail due to invalid passphrase
+	curve, k, rest, err = DecryptAndUnmarshalSigningPrivateKey([]byte("invalid passphrase"), privKey)
+	assert.EqualError(t, err, "invalid passphrase or corrupt private key")
+	assert.Nil(t, k)
+	assert.Equal(t, rest, []byte{})
+}
+
+func TestEncryptAndMarshalSigningPrivateKey(t *testing.T) {
+	// Having proved that decryption works correctly above, we can test the
+	// encryption function produces a value which can be decrypted
+	passphrase := []byte("passphrase")
+	bytes := []byte("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA")
+	kdfParams := NewArgon2Parameters(64*1024, 4, 3)
+	key, err := EncryptAndMarshalSigningPrivateKey(Curve_CURVE25519, bytes, passphrase, kdfParams)
+	assert.Nil(t, err)
+
+	// Verify the "key" can be decrypted successfully
+	curve, k, rest, err := DecryptAndUnmarshalSigningPrivateKey(passphrase, key)
+	assert.Len(t, k, 64)
+	assert.Equal(t, Curve_CURVE25519, curve)
+	assert.Equal(t, rest, []byte{})
+	assert.Nil(t, err)
+
+	// EncryptAndMarshalEd25519PrivateKey does not create any errors itself
+}