Keymanager 'disk' implementation

conf/server/server.conf

@@ -35,5 +35,11 @@ providers {
     }
 
     # KeyManager "memory": A key manager for generating keys and signing certificates that stores keys in memory.
-    KeyManager "memory" {}
-}
+    # KeyManager "memory" {}
+
+    # KeyManager "disk": A key manager for generating keys that stores keys on disk.
+    KeyManager "disk" {
+        # keys_file_path: Path to the file where the key manager will store keys.
+        keys_file_path = "./keys.json"
+    }
+}

pkg/common/jwt/validator_test.go

@@ -19,7 +19,7 @@ var (
 
 func Setup(t *testing.T) (*JWTCA, *DefaultJWTValidator) {
 	ctx := context.Background()
-	km := keymanager.New(&keymanager.Config{})
+	km := keymanager.NewMemoryKeyManager(nil)
 	config := ValidatorConfig{
 		KeyManager:       km,
 		ExpectedAudience: expAud,

pkg/common/keymanager/base.go

@@ -11,10 +11,10 @@ import (
 	"github.com/HewlettPackard/galadriel/pkg/common/cryptoutil"
 )
 
-// Base is a base implementation of KeyManager that can be embedded into
+// base implementation of KeyManager that can be embedded into
 // other KeyManager implementations (e.g. memory and disk).
-type Base struct {
-	mu sync.RWMutex
+type base struct {
+	mu *sync.RWMutex
 
 	generator Generator
 	entries   map[string]*KeyEntry
@@ -28,21 +28,22 @@ type KeyEntry struct {
 	id         string
 }
 
-// Config is the configuration for a Base KeyManager.
+// Config is the configuration for a base KeyManager.
 type Config struct {
 	// Optional Key Generator
 	Generator Generator
 }
 
-// New creates a new Base KeyManager.
-func New(config *Config) *Base {
+// newBase creates a new base KeyManager.
+func newBase(config *Config) *base {
 	if config == nil {
 		config = &Config{}
 	}
 	if config.Generator == nil {
 		config.Generator = &defaultGenerator{}
 	}
-	return &Base{
+	return &base{
+		mu:        &sync.RWMutex{},
 		generator: config.Generator,
 		entries:   make(map[string]*KeyEntry),
 	}
@@ -68,7 +69,7 @@ func (k *KeyEntry) Signer() crypto.Signer {
 }
 
 // GenerateKey creates a new key pair and stores it in the KeyManager.
-func (b *Base) GenerateKey(ctx context.Context, keyID string, keyType cryptoutil.KeyType) (Key, error) {
+func (b *base) GenerateKey(ctx context.Context, keyID string, keyType cryptoutil.KeyType) (Key, error) {
 	if keyID == "" {
 		return nil, errors.New("key id is required")
 	}
@@ -89,7 +90,7 @@ func (b *Base) GenerateKey(ctx context.Context, keyID string, keyType cryptoutil
 	return newEntry, nil
 }
 
-func (b *Base) GetKey(ctx context.Context, id string) (Key, error) {
+func (b *base) GetKey(ctx context.Context, id string) (Key, error) {
 	b.mu.RLock()
 	defer b.mu.RUnlock()
 
@@ -101,7 +102,7 @@ func (b *Base) GetKey(ctx context.Context, id string) (Key, error) {
 	return entry, nil
 }
 
-func (b *Base) GetKeys(ctx context.Context) ([]Key, error) {
+func (b *base) GetKeys(ctx context.Context) ([]Key, error) {
 	b.mu.RLock()
 	defer b.mu.RUnlock()
 
@@ -113,7 +114,7 @@ func (b *Base) GetKeys(ctx context.Context) ([]Key, error) {
 	return keys, nil
 }
 
-func (b *Base) generateKeyEntry(keyID string, keyType cryptoutil.KeyType) (*KeyEntry, error) {
+func (b *base) generateKeyEntry(keyID string, keyType cryptoutil.KeyType) (*KeyEntry, error) {
 	var err error
 	var privateKey crypto.Signer
 

pkg/common/keymanager/base_test.go

@@ -8,8 +8,8 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func setup() (*Base, context.Context) {
-	b := New(&Config{})
+func setup() (*base, context.Context) {
+	b := newBase(&Config{})
 	ctx := context.Background()
 	return b, ctx
 }

pkg/common/keymanager/disk.go

@@ -0,0 +1,143 @@
+package keymanager
+
+import (
+	"context"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/json"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/HewlettPackard/galadriel/pkg/common/cryptoutil"
+)
+
+const keyFilePerm = 0600
+
+// Disk extends the base KeyManager to store keys in disk.
+type Disk struct {
+	base
+
+	keysFilePath string
+}
+
+// NewDiskKeyManager creates a new Disk that stores keys in disk.
+func NewDiskKeyManager(generator Generator, keysFilePath string) (*Disk, error) {
+	c := &Config{
+		Generator: generator,
+	}
+	base := newBase(c)
+
+	diskKeyManager := &Disk{
+		base:         *base,
+		keysFilePath: keysFilePath,
+	}
+
+	err := diskKeyManager.loadKeysFromDisk()
+	if err != nil {
+		return nil, err
+	}
+
+	return diskKeyManager, nil
+}
+
+// GenerateKey generates a new key and stores it in disk.
+func (d *Disk) GenerateKey(ctx context.Context, keyID string, keyType cryptoutil.KeyType) (Key, error) {
+	key, err := d.base.GenerateKey(ctx, keyID, keyType)
+	if err != nil {
+		return nil, err
+	}
+
+	err = d.saveKeysToDisk()
+	if err != nil {
+		return nil, err
+	}
+
+	return key, nil
+}
+
+func (d *Disk) loadKeysFromDisk() error {
+	data, err := os.ReadFile(d.keysFilePath)
+	if err != nil {
+		return nil // No keys file exists, no error
+	}
+
+	keys := make(map[string]string)
+	if err := json.Unmarshal(data, &keys); err != nil {
+		return fmt.Errorf("failed to unmarshal keys from disk: %w", err)
+	}
+
+	d.mu.RLock()
+	defer d.mu.RUnlock()
+
+	for id, keyBytes := range keys {
+		signer, err := convertToSigner([]byte(keyBytes))
+		if err != nil {
+			return fmt.Errorf("failed to create key entry: %w", err)
+		}
+
+		d.entries[id] = &KeyEntry{
+			PrivateKey: signer,
+			PublicKey:  signer.Public(),
+			id:         id,
+		}
+	}
+
+	return nil
+}
+
+// SaveKeysToDisk saves the keys in the key manager to disk.
+func (d *Disk) saveKeysToDisk() error {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	keys := make(map[string]string)
+	for id, entry := range d.entries {
+		keyBytes, err := x509.MarshalPKCS8PrivateKey(entry.PrivateKey)
+		if err != nil {
+			return fmt.Errorf("failed to marshal private key: %w", err)
+		}
+
+		// Encode PEM block as string
+		keyPEM := pem.EncodeToMemory(&pem.Block{
+			Type:  "PRIVATE KEY",
+			Bytes: keyBytes,
+		})
+		keys[id] = string(keyPEM)
+	}
+
+	data, err := json.Marshal(keys)
+	if err != nil {
+		return fmt.Errorf("failed to serialize keys: %w", err)
+	}
+
+	if err := os.WriteFile(d.keysFilePath, data, keyFilePerm); err != nil {
+		return fmt.Errorf("failed to write keys to disk: %w", err)
+	}
+
+	return nil
+}
+
+func convertToSigner(keyBytes []byte) (crypto.Signer, error) {
+	block, _ := pem.Decode(keyBytes)
+	if block == nil {
+		return nil, errors.New("failed to decode PEM block containing private key")
+	}
+
+	key, err := x509.ParsePKCS8PrivateKey(block.Bytes)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse private key: %w", err)
+	}
+
+	switch key := key.(type) {
+	case *rsa.PrivateKey:
+		return key, nil
+	case *ecdsa.PrivateKey:
+		return key, nil
+	default:
+		return nil, errors.New("unsupported private key type")
+	}
+}

pkg/common/keymanager/disk_test.go

@@ -0,0 +1,57 @@
+package keymanager
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/HewlettPackard/galadriel/pkg/common/cryptoutil"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDiskKeyManager(t *testing.T) {
+	tempDir, err := os.MkdirTemp("", "keymanager_test")
+	require.NoError(t, err)
+	defer os.RemoveAll(tempDir)
+
+	dataDir := filepath.Join(tempDir, "keys-test.json")
+
+	// Create a new Disk key manager
+	keyManager, err := NewDiskKeyManager(nil, dataDir)
+	require.NoError(t, err)
+
+	// Generate a new key pair
+	keyID := "key1"
+	keyType := cryptoutil.RSA2048
+	key, err := keyManager.GenerateKey(context.Background(), keyID, keyType)
+	require.NoError(t, err)
+	require.NotNil(t, key)
+
+	// Get the generated key
+	gotKey, err := keyManager.GetKey(context.Background(), keyID)
+	require.NoError(t, err)
+	require.NotNil(t, gotKey)
+
+	// Verify the generated key's ID and type
+	assert.Equal(t, keyID, gotKey.ID())
+
+	// Verify the generated key's
+	assert.NotNil(t, gotKey.Signer())
+
+	// Load the Disk key manager from disk
+	loadedKeyManager, err := NewDiskKeyManager(nil, dataDir)
+	require.NoError(t, err)
+
+	// Get the loaded key
+	loadedKey, err := loadedKeyManager.GetKey(context.Background(), keyID)
+	require.NoError(t, err)
+	require.NotNil(t, loadedKey)
+
+	// Verify the loaded key's ID and type
+	assert.Equal(t, keyID, loadedKey.ID())
+
+	// Verify the loaded key's
+	assert.NotNil(t, loadedKey.Signer())
+}

pkg/common/keymanager/keymanager.go

@@ -8,7 +8,7 @@ import (
 	"github.com/HewlettPackard/galadriel/pkg/common/cryptoutil"
 )
 
-// KeyManager provides a common interface for managing keys.
+// Memory provides a common interface for managing keys.
 type KeyManager interface {
 	// GenerateKey generates a new key with the given ID and key type.
 	// If a key with that ID already exists, it is overwritten.
@@ -18,7 +18,7 @@ type KeyManager interface {
 	// an error is returned.
 	GetKey(ctx context.Context, id string) (Key, error)
 
-	// GetKeys returns all keys managed by the KeyManager.
+	// GetKeys returns all keys managed by the Memory.
 	GetKeys(ctx context.Context) ([]Key, error)
 }
 

pkg/common/keymanager/memory.go

@@ -0,0 +1,14 @@
+package keymanager
+
+// Memory is a key manager that keeps keys in memory.
+type Memory struct {
+	*base
+}
+
+func NewMemoryKeyManager(generator Generator) *Memory {
+	return &Memory{
+		base: newBase(&Config{
+			Generator: generator,
+		}),
+	}
+}

pkg/common/keymanager/memory/keymanager_test.go → pkg/common/keymanager/memory_test.go

@@ -1,4 +1,4 @@
-package memory
+package keymanager
 
 import (
 	"context"
@@ -9,12 +9,12 @@ import (
 )
 
 func TestNew(t *testing.T) {
-	km := New(nil)
+	km := newBase(nil)
 	assert.NotNil(t, km)
 }
 
 func TestKeyManager(t *testing.T) {
-	km := New(nil)
+	km := newBase(nil)
 	ctx := context.Background()
 
 	key1, err := km.GenerateKey(ctx, "foo", cryptoutil.RSA2048)