Separate cli into its own module; rename it to sp

sp/crypto/cbc.go

@@ -0,0 +1,68 @@
+package crypto
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"fmt"
+	"io"
+
+	"github.com/ncw/rclone/backend/crypt/pkcs7"
+)
+
+func CBCEncrypt(key []byte, plaintext []byte) ([]byte, error) {
+	if len(key) != 32 {
+		return nil, fmt.Errorf("key is not 32 bytes")
+	}
+
+	plaintext = pkcs7.Pad(aes.BlockSize, plaintext)
+
+	if len(plaintext)%aes.BlockSize != 0 {
+		return nil, fmt.Errorf("plaintext is not a multiple of the block size")
+	}
+
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	ciphertext := make([]byte, aes.BlockSize+len(plaintext))
+	iv := ciphertext[:aes.BlockSize]
+
+	if _, err := io.ReadFull(rand.Reader, iv); err != nil {
+		return nil, err
+	}
+
+	mode := cipher.NewCBCEncrypter(block, iv)
+	mode.CryptBlocks(ciphertext[aes.BlockSize:], plaintext)
+
+	return ciphertext, nil
+}
+
+func CBCDecrypt(key []byte, ciphertext []byte) ([]byte, error) {
+	if len(key) != 32 {
+		return nil, fmt.Errorf("key is not 32 bytes")
+	}
+
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(ciphertext) < aes.BlockSize {
+		return nil, err
+	}
+
+	iv := ciphertext[:aes.BlockSize]
+
+	ciphertext = ciphertext[aes.BlockSize:]
+
+	if len(ciphertext)%aes.BlockSize != 0 {
+		return nil, fmt.Errorf("ciphertext is not a multiple of the block size")
+	}
+
+	mode := cipher.NewCBCDecrypter(block, iv)
+	mode.CryptBlocks(ciphertext, ciphertext)
+
+	return pkcs7.Unpad(aes.BlockSize, ciphertext)
+}

sp/crypto/gcm.go

@@ -0,0 +1,60 @@
+package crypto
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"errors"
+	"fmt"
+	"io"
+)
+
+func GCMEncrypt(key []byte, plaintext []byte) ([]byte, error) {
+	if len(key) != 32 {
+		return nil, fmt.Errorf("key is not 32 bytes")
+	}
+
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return nil, err
+	}
+
+	nonce := make([]byte, gcm.NonceSize())
+	_, err = io.ReadFull(rand.Reader, nonce)
+	if err != nil {
+		return nil, err
+	}
+
+	return gcm.Seal(nonce, nonce, plaintext, nil), nil
+}
+
+func GCMDecrypt(key []byte, ciphertext []byte) ([]byte, error) {
+	if len(key) != 32 {
+		return nil, fmt.Errorf("key is not 32 bytes")
+	}
+
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(ciphertext) < gcm.NonceSize() {
+		return nil, errors.New("malformed ciphertext")
+	}
+
+	return gcm.Open(nil,
+		ciphertext[:gcm.NonceSize()],
+		ciphertext[gcm.NonceSize():],
+		nil,
+	)
+}

sp/crypto/helpers.go

@@ -0,0 +1,68 @@
+package crypto
+
+import (
+	"fmt"
+	"math/rand"
+	"time"
+)
+
+func GenerateKeyFromPassword(pass []byte) ([]byte, error) {
+	if len(pass) < 8 {
+		return nil, fmt.Errorf("master password must be at least 8 characters")
+	}
+
+	for idx := 0; len(pass) < 32; idx++ {
+		pass = append(pass, pass[idx])
+
+		if idx == len(pass) {
+			idx = 0
+		}
+	}
+
+	return pass, nil
+}
+
+func CombinePasswordAndKey(pass, key []byte) ([]byte, error) {
+	if len(pass) < 8 {
+		return nil, fmt.Errorf("master password must be at least 8 characters")
+	}
+	if len(key) != 16 {
+		return nil, fmt.Errorf("key was not of length 16")
+	}
+
+	for idx := 0; len(pass) < 16; idx++ {
+		pass = append(pass, pass[idx])
+	}
+
+	return append(pass[:16], key...), nil
+}
+
+func GeneratePassword(length int, numbers, specials bool) string {
+	const alphas = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+	const alphanumerics = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890"
+	const alphasAndSpecials = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890!@#$%^&*()"
+	const alphanumericsAndSpecials = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890!@#$%^&*()"
+	rand.Seed(time.Now().UnixNano())
+	pass := make([]byte, length)
+
+	switch {
+	case numbers && specials:
+		for idx := 0; idx < length; idx++ {
+			pass[idx] = alphanumericsAndSpecials[rand.Int63()%int64(len(alphanumericsAndSpecials))]
+		}
+	case numbers:
+		for idx := 0; idx < length; idx++ {
+			pass[idx] = alphanumerics[rand.Int63()%int64(len(alphanumerics))]
+		}
+	case specials:
+		for idx := 0; idx < length; idx++ {
+			pass[idx] = alphasAndSpecials[rand.Int63()%int64(len(alphasAndSpecials))]
+		}
+	default:
+		for idx := 0; idx < length; idx++ {
+			pass[idx] = alphas[rand.Int63()%int64(len(alphas))]
+		}
+	}
+
+	return string(pass)
+}

sp/crypto/pbkdf2.go

@@ -0,0 +1,16 @@
+package crypto
+
+import (
+	"crypto/sha256"
+
+	"golang.org/x/crypto/pbkdf2"
+)
+
+const (
+	PBKDF2Rounds = 4096
+	KeyLength    = 32
+)
+
+func GeneratePBKDF2Key(password, salt []byte) []byte {
+	return pbkdf2.Key([]byte(password), []byte(salt), PBKDF2Rounds, KeyLength, sha256.New)
+}