first commit

framework/encrypt/encrypt.go

@@ -0,0 +1,155 @@
+// Package encrypt provides reversible AES-256-GCM encryption and decryption utilities
+// for securing sensitive data like API keys and credentials.
+package encrypt
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+
+	"github.com/maximhq/bifrost/core/schemas"
+	"golang.org/x/crypto/argon2"
+	"golang.org/x/crypto/bcrypt"
+)
+
+var encryptionKey []byte
+var logger schemas.Logger	
+
+var ErrEncryptionKeyNotInitialized = errors.New("encryption key is not initialized")
+
+// Init initializes the encryption key using Argon2id KDF to derive a secure 32-byte key
+// from the provided passphrase. This ensures strong entropy regardless of passphrase length.
+// The function accepts any passphrase but warns if it's too short (< 16 bytes).
+func Init(key string, _logger schemas.Logger) {
+	logger = _logger
+	if key == "" {
+		encryptionKey = nil
+		logger.Warn("encryption key is not set, encryption will be disabled. To set encryption key: use the encryption_key field in the configuration file or set the BIFROST_ENCRYPTION_KEY environment variable. Note that - once encryption key is set, it cannot be changed later unless you clean up the database.")
+		return
+	}
+
+	// Warn if passphrase is too short
+	if len(key) < 16 {
+		logger.Warn("encryption passphrase is shorter than 16 bytes, consider using a longer passphrase for better security")
+	}
+
+	// Derive a secure 32-byte key using Argon2id KDF
+	// We use a fixed salt since this is a system-wide encryption key (not per-user passwords)
+	// Argon2id parameters: time=1, memory=64MB, threads=4, keyLen=32
+	// This provides strong security while maintaining reasonable performance for initialization
+	salt := []byte("bifrost-encryption-v1-salt-2024")
+	encryptionKey = argon2.IDKey([]byte(key), salt, 1, 64*1024, 4, 32)
+}
+
+// CompareHash compares a hash and a password
+func CompareHash(hash string, password string) (bool, error) {
+	err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(password))
+	if err != nil {
+		if errors.Is(err, bcrypt.ErrMismatchedHashAndPassword) {
+			return false, nil
+		}
+		return false, fmt.Errorf("failed to compare hash: %w", err)
+	}
+	return true, nil
+}
+
+// Hash hashes a password using bcrypt
+func Hash(password string) (string, error) {
+	hashedPassword, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+	if err != nil {
+		return "", fmt.Errorf("failed to hash password: %w", err)
+	}
+	return string(hashedPassword), nil
+}
+
+// Encrypt encrypts a plaintext string using AES-256-GCM and returns a base64-encoded ciphertext
+func Encrypt(plaintext string) (string, error) {
+	if encryptionKey == nil {
+		return plaintext, nil
+	}
+	if plaintext == "" {
+		return "", nil
+	}
+
+	block, err := aes.NewCipher(encryptionKey)
+	if err != nil {
+		return plaintext, fmt.Errorf("failed to create cipher: %w", err)
+	}
+
+	aesGCM, err := cipher.NewGCM(block)
+	if err != nil {
+		return plaintext, fmt.Errorf("failed to create GCM: %w", err)
+	}
+
+	// Create a nonce (number used once)
+	nonce := make([]byte, aesGCM.NonceSize())
+	if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
+		return plaintext, fmt.Errorf("failed to read nonce: %w", err)
+	}
+
+	// Encrypt the data
+	ciphertext := aesGCM.Seal(nonce, nonce, []byte(plaintext), nil)
+
+	// Encode to base64 for storage
+	return base64.StdEncoding.EncodeToString(ciphertext), nil
+}
+
+// IsEnabled returns true if the encryption key has been initialized
+func IsEnabled() bool {
+	return encryptionKey != nil
+}
+
+// HashSHA256 returns a deterministic hex-encoded SHA-256 hash of the input.
+// Used for hash-based lookups on encrypted columns (e.g., virtual key value, session token).
+func HashSHA256(value string) string {
+	h := sha256.Sum256([]byte(value))
+	return hex.EncodeToString(h[:])
+}
+
+// Decrypt decrypts a base64-encoded ciphertext using AES-256-GCM and returns the plaintext
+func Decrypt(ciphertext string) (string, error) {
+	if encryptionKey == nil {
+		return ciphertext, ErrEncryptionKeyNotInitialized
+	}
+	if ciphertext == "" {
+		return ciphertext, nil
+	}
+
+	// Decode from base64
+	data, err := base64.StdEncoding.DecodeString(ciphertext)
+	if err != nil {
+		return "", fmt.Errorf("failed to decode base64: %w", err)
+	}
+
+	block, err := aes.NewCipher(encryptionKey)
+	if err != nil {
+		return "", fmt.Errorf("failed to create cipher: %w", err)
+	}
+
+	aesGCM, err := cipher.NewGCM(block)
+	if err != nil {
+		return "", fmt.Errorf("failed to create GCM: %w", err)
+	}
+
+	// Extract nonce
+	nonceSize := aesGCM.NonceSize()
+	if len(data) < nonceSize {
+		return "", fmt.Errorf("ciphertext too short")
+	}
+
+	nonce, ciphertextBytes := data[:nonceSize], data[nonceSize:]
+
+	// Decrypt the data
+	plaintext, err := aesGCM.Open(nil, nonce, ciphertextBytes, nil)
+	if err != nil {
+		return "", fmt.Errorf("failed to decrypt: %w", err)
+	}
+
+	return string(plaintext), nil
+}