Add new attachment processor that uses pre-allocated buffer (#120)

crypto/attachment_manual_test.go

@@ -0,0 +1,176 @@
+package crypto
+
+import (
+	"bytes"
+	"io"
+	"testing"
+
+	"github.com/pkg/errors"
+)
+
+func TestManualAttachmentProcessor(t *testing.T) {
+	pgp.latestServerTime = 1615394034
+	defer func() { pgp.latestServerTime = testTime }()
+	passphrase := []byte("wUMuF/lkDPYWH/0ZqqY8kJKw7YJg6kS")
+	pk, err := NewKeyFromArmored(readTestFile("att_key", false))
+	if err != nil {
+		t.Error("Expected no error while unarmoring private key, got:" + err.Error())
+	}
+
+	uk, err := pk.Unlock(passphrase)
+	if err != nil {
+		t.Error("Expected no error while unlocking private key, got:" + err.Error())
+	}
+
+	defer uk.ClearPrivateParams()
+
+	ukr, err := NewKeyRing(uk)
+	if err != nil {
+		t.Error("Expected no error while building private keyring, got:" + err.Error())
+	}
+
+	inputPlaintext := readTestFile("att_cleartext", false)
+	plaintextBytes := []byte(inputPlaintext)
+	plaintextReader := bytes.NewReader(plaintextBytes)
+	bufferLen := 2 * len(plaintextBytes)
+	dataPacket := make([]byte, bufferLen)
+	ap, err := ukr.NewManualAttachmentProcessor(
+		len(plaintextBytes),
+		"test.txt",
+		dataPacket,
+	)
+	if err != nil {
+		t.Error("Expected no error while building the attachment processor, got:" + err.Error())
+	}
+	chunkSize := 1 << 10
+	inputBytes := make([]byte, chunkSize)
+	var readAllPlaintext = false
+	for !readAllPlaintext {
+		nBytesRead, err := plaintextReader.Read(inputBytes)
+		if errors.Is(err, io.EOF) {
+			readAllPlaintext = true
+		} else if err != nil {
+			t.Error("Expected no error while reading plain data, got:" + err.Error())
+		}
+		err = ap.Process(inputBytes[:nBytesRead])
+		if err != nil {
+			t.Error("Expected no error while writing plain data, got:" + err.Error())
+		}
+	}
+	err = ap.Finish()
+	if err != nil {
+		t.Error("Expected no error while calling finish, got:" + err.Error())
+	}
+	dataLength := ap.GetDataLength()
+	keyPacket := ap.GetKeyPacket()
+	if keyPacket == nil {
+		t.Error("The key packet was nil")
+	}
+	if len(keyPacket) == 0 {
+		t.Error("The key packet was empty")
+	}
+	t.Logf("buffer size : %d total written : %d", bufferLen, dataLength)
+	if dataLength > bufferLen {
+		t.Errorf("Wrote more than was allocated, buffer size : %d total written : %d", bufferLen, dataLength)
+	}
+
+	pgpMsg := NewPGPSplitMessage(keyPacket, dataPacket[:dataLength]).GetPGPMessage()
+	plainMsg, err := ukr.Decrypt(pgpMsg, nil, 0)
+	if err != nil {
+		t.Error("Expected no error while decrypting, got:" + err.Error())
+	}
+	outputPlaintext := string(plainMsg.Data)
+	if outputPlaintext != inputPlaintext {
+		t.Errorf("Expectedplaintext to be %s got %s", inputPlaintext, outputPlaintext)
+	}
+}
+
+func TestManualAttachmentProcessorNotEnoughBuffer(t *testing.T) {
+	pgp.latestServerTime = 1615394034
+	defer func() { pgp.latestServerTime = testTime }()
+	passphrase := []byte("wUMuF/lkDPYWH/0ZqqY8kJKw7YJg6kS")
+	pk, err := NewKeyFromArmored(readTestFile("att_key", false))
+	if err != nil {
+		t.Error("Expected no error while unarmoring private key, got:" + err.Error())
+	}
+
+	uk, err := pk.Unlock(passphrase)
+	if err != nil {
+		t.Error("Expected no error while unlocking private key, got:" + err.Error())
+	}
+
+	defer uk.ClearPrivateParams()
+
+	ukr, err := NewKeyRing(uk)
+	if err != nil {
+		t.Error("Expected no error while building private keyring, got:" + err.Error())
+	}
+
+	inputPlaintext := readTestFile("att_cleartext", false)
+	plaintextBytes := []byte(inputPlaintext)
+	plaintextReader := bytes.NewReader(plaintextBytes)
+	bufferLen := len(plaintextBytes) / 2
+	dataPacket := make([]byte, bufferLen)
+	ap, err := ukr.NewManualAttachmentProcessor(
+		len(plaintextBytes),
+		"test.txt",
+		dataPacket,
+	)
+	if err != nil {
+		t.Error("Expected no error while building the attachment processor, got:" + err.Error())
+	}
+	chunkSize := 1 << 10
+	inputBytes := make([]byte, chunkSize)
+	var readAllPlaintext = false
+	for !readAllPlaintext {
+		nBytesRead, err := plaintextReader.Read(inputBytes)
+		if errors.Is(err, io.EOF) {
+			readAllPlaintext = true
+		} else if err != nil {
+			t.Error("Expected no error while reading plain data, got:" + err.Error())
+		}
+		err = ap.Process(inputBytes[:nBytesRead])
+		if err != nil {
+			t.Error("Expected no error while writing plain data, got:" + err.Error())
+		}
+	}
+	err = ap.Finish()
+	if err == nil {
+		t.Error("Expected an error while calling finish, got nil")
+	}
+}
+
+func TestManualAttachmentProcessorEmptyBuffer(t *testing.T) {
+	pgp.latestServerTime = 1615394034
+	defer func() { pgp.latestServerTime = testTime }()
+	passphrase := []byte("wUMuF/lkDPYWH/0ZqqY8kJKw7YJg6kS")
+	pk, err := NewKeyFromArmored(readTestFile("att_key", false))
+	if err != nil {
+		t.Error("Expected no error while unarmoring private key, got:" + err.Error())
+	}
+
+	uk, err := pk.Unlock(passphrase)
+	if err != nil {
+		t.Error("Expected no error while unlocking private key, got:" + err.Error())
+	}
+
+	defer uk.ClearPrivateParams()
+
+	ukr, err := NewKeyRing(uk)
+	if err != nil {
+		t.Error("Expected no error while building private keyring, got:" + err.Error())
+	}
+
+	inputPlaintext := readTestFile("att_cleartext", false)
+	plaintextBytes := []byte(inputPlaintext)
+	bufferLen := 0
+	dataPacket := make([]byte, bufferLen)
+	_, err = ukr.NewManualAttachmentProcessor(
+		len(plaintextBytes),
+		"test.txt",
+		dataPacket,
+	)
+	if err == nil {
+		t.Error("Expected an error while building the attachment processor with an empty buffer got nil")
+	}
+}