From 4a41ea9e27944fc1170ad4e10d9aca038590d348 Mon Sep 17 00:00:00 2001
From: Aron Wussler <aron@wussler.it>
Date: Thu, 12 Sep 2019 11:33:17 +0200
Subject: [PATCH] Add wrappers for iOS

---
 helper/ios.go      | 42 +++++++++++++++++++++++++++++++++++++
 helper/ios_test.go | 52 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 94 insertions(+)
 create mode 100644 helper/ios.go
 create mode 100644 helper/ios_test.go

diff --git a/helper/ios.go b/helper/ios.go
new file mode 100644
index 0000000..22a433d
--- /dev/null
+++ b/helper/ios.go
@@ -0,0 +1,42 @@
+package helper
+
+import (
+	"github.com/ProtonMail/gopenpgp/crypto"
+)
+
+type ExplicitVerifyMessage struct {
+	Message *crypto.PlainMessage
+	SignatureVerificationError *crypto.SignatureVerificationError
+}
+
+// DecryptVerifyMessageArmored decrypts an armored PGP message given a private key and its passphrase
+// and verifies the embedded signature.
+// Returns the plain data or an error on signature verification failure.
+func DecryptExplicitVerify(
+	pgpMessage *crypto.PGPMessage,
+	privateKeyRing, publicKeyRing *crypto.KeyRing,
+	verifyTime int64,
+) (*ExplicitVerifyMessage, error) {
+	var explicitVerify *ExplicitVerifyMessage
+
+	message, err := privateKeyRing.Decrypt(pgpMessage, publicKeyRing, verifyTime);
+
+	if err != nil {
+		castedErr, isType := err.(crypto.SignatureVerificationError)
+		if !isType {
+			return nil, err
+		}
+
+		explicitVerify = &ExplicitVerifyMessage{
+			Message: message,
+			SignatureVerificationError: &castedErr,
+		}
+	} else {
+		explicitVerify = &ExplicitVerifyMessage{
+			Message: message,
+			SignatureVerificationError: nil,
+		}
+	}
+
+	return explicitVerify, nil
+}
diff --git a/helper/ios_test.go b/helper/ios_test.go
new file mode 100644
index 0000000..0916755
--- /dev/null
+++ b/helper/ios_test.go
@@ -0,0 +1,52 @@
+package helper
+
+import (
+	"testing"
+
+	"github.com/ProtonMail/gopenpgp/constants"
+	"github.com/ProtonMail/gopenpgp/crypto"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIOSSignedMessageDecryption(t *testing.T) {
+	testPrivateKeyRing, _ := pgp.BuildKeyRingArmored(readTestFile("keyring_privateKey", false))
+	testPublicKeyRing, _ := pgp.BuildKeyRingArmored(readTestFile("mime_publicKey", false))
+
+	// Password defined in base_test
+	err := testPrivateKeyRing.UnlockWithPassphrase(testMailboxPassword)
+	if err != nil {
+		t.Fatal("Expected no error unlocking privateKey, got:", err)
+	}
+
+	pgpMessage, err := crypto.NewPGPMessageFromArmored(readTestFile("message_signed", false))
+	if err != nil {
+		t.Fatal("Expected no error when unarmoring, got:", err)
+	}
+
+	decrypted, err := DecryptExplicitVerify(pgpMessage, testPrivateKeyRing, testPublicKeyRing, pgp.GetUnixTime())
+	if err != nil {
+		t.Fatal("Expected no error when decrypting, got:", err)
+	}
+
+	assert.Exactly(t, constants.SIGNATURE_NO_VERIFIER, decrypted.SignatureVerificationError.Status)
+	assert.Exactly(t, readTestFile("message_plaintext", true), decrypted.Message.GetString())
+
+	testPublicKeyRing, _ = pgp.BuildKeyRingArmored(readTestFile("keyring_publicKey", false))
+
+	pgpMessage, err = testPublicKeyRing.Encrypt(decrypted.Message, testPrivateKeyRing)
+	if err != nil {
+		t.Fatal("Expected no error when encrypting, got:", err)
+	}
+
+	decrypted, err = DecryptExplicitVerify(pgpMessage, testPrivateKeyRing, testPublicKeyRing, pgp.GetUnixTime())
+	if err != nil {
+		t.Fatal("Expected no error when decrypting, got:", err)
+	}
+
+	assert.Nil(t, decrypted.SignatureVerificationError)
+	assert.Exactly(t, readTestFile("message_plaintext", true), decrypted.Message.GetString())
+
+	decrypted, err = DecryptExplicitVerify(pgpMessage, testPublicKeyRing, testPublicKeyRing, pgp.GetUnixTime())
+	assert.NotNil(t, err)
+	assert.Nil(t, decrypted)
+}