Changed LoadKeyFromSSLibBytes to Support RSA Keys

signerverifier/ecdsa.go

@@ -95,7 +95,7 @@ func LoadECDSAKeyFromFile(path string) (*SSLibKey, error) {
 		return nil, fmt.Errorf("unable to load ECDSA key from file: %w", err)
 	}
 
-	return loadKeyFromSSLibBytes(contents)
+	return LoadKeyFromSSLibBytes(contents)
 }
 
 func getECDSAHashedData(data []byte, curveSize int) []byte {

signerverifier/ed25519.go

@@ -94,5 +94,5 @@ func LoadED25519KeyFromFile(path string) (*SSLibKey, error) {
 		return nil, fmt.Errorf("unable to load ED25519 key from file: %w", err)
 	}
 
-	return loadKeyFromSSLibBytes(contents)
+	return LoadKeyFromSSLibBytes(contents)
 }

signerverifier/rsa.go

@@ -100,6 +100,13 @@ func LoadRSAPSSKeyFromFile(path string) (*SSLibKey, error) {
 		return nil, fmt.Errorf("unable to load RSA key from file: %w", err)
 	}
 
+	return LoadRSAPSSKeyFromBytes(contents)
+}
+
+// LoadRSAPSSKeyFromBytes is a function that takes a byte array as input. This byte array should represent a PEM encoded RSA key, as PEM encoding is required.
+// The function returns an SSLibKey instance, which is a struct that holds the key data.
+
+func LoadRSAPSSKeyFromBytes(contents []byte) (*SSLibKey, error) {
 	pemData, keyObj, err := decodeAndParsePEM(contents)
 	if err != nil {
 		return nil, fmt.Errorf("unable to load RSA key from file: %w", err)
@@ -112,20 +119,13 @@ func LoadRSAPSSKeyFromFile(path string) (*SSLibKey, error) {
 		KeyVal:              KeyVal{},
 	}
 
-	switch k := keyObj.(type) {
-	case *rsa.PublicKey:
-		pubKeyBytes, err := x509.MarshalPKIXPublicKey(k)
-		if err != nil {
-			return nil, fmt.Errorf("unable to load RSA key from file: %w", err)
-		}
-		key.KeyVal.Public = strings.TrimSpace(string(generatePEMBlock(pubKeyBytes, PublicKeyPEM)))
+	pubKeyBytes, err := marshalAndGeneratePEM(keyObj)
+	if err != nil {
+		return nil, fmt.Errorf("unable to load RSA key from file: %w", err)
+	}
+	key.KeyVal.Public = strings.TrimSpace(string(pubKeyBytes))
 
-	case *rsa.PrivateKey:
-		pubKeyBytes, err := x509.MarshalPKIXPublicKey(k.Public())
-		if err != nil {
-			return nil, fmt.Errorf("unable to load RSA key from file: %w", err)
-		}
-		key.KeyVal.Public = strings.TrimSpace(string(generatePEMBlock(pubKeyBytes, PublicKeyPEM)))
+	if _, ok := keyObj.(*rsa.PrivateKey); ok {
 		key.KeyVal.Private = strings.TrimSpace(string(generatePEMBlock(pemData.Bytes, RSAPrivateKeyPEM)))
 	}
 
@@ -139,3 +139,23 @@ func LoadRSAPSSKeyFromFile(path string) (*SSLibKey, error) {
 
 	return key, nil
 }
+
+func marshalAndGeneratePEM(key interface{}) ([]byte, error) {
+	var pubKeyBytes []byte
+	var err error
+
+	switch k := key.(type) {
+	case *rsa.PublicKey:
+		pubKeyBytes, err = x509.MarshalPKIXPublicKey(k)
+	case *rsa.PrivateKey:
+		pubKeyBytes, err = x509.MarshalPKIXPublicKey(k.Public())
+	default:
+		return nil, fmt.Errorf("unexpected key type: %T", k)
+	}
+
+	if err != nil {
+		return nil, err
+	}
+
+	return generatePEMBlock(pubKeyBytes, PublicKeyPEM), nil
+}

signerverifier/utils.go

@@ -24,15 +24,14 @@ var (
 	ErrFailedPEMParsing = errors.New("failed parsing the PEM block: unsupported PEM type")
 )
 
-// loadKeyFromSSLibBytes returns a pointer to a Key instance created from the
+// LoadKeyFromSSLibBytes returns a pointer to a Key instance created from the
 // contents of the bytes. The key contents are expected to be in the custom
 // securesystemslib format.
-func loadKeyFromSSLibBytes(contents []byte) (*SSLibKey, error) {
+func LoadKeyFromSSLibBytes(contents []byte) (*SSLibKey, error) {
 	var key *SSLibKey
 	if err := json.Unmarshal(contents, &key); err != nil {
-		return nil, err
+		return LoadRSAPSSKeyFromBytes(contents)
 	}
-
 	if len(key.KeyID) == 0 {
 		keyID, err := calculateKeyID(key)
 		if err != nil {

signerverifier/utils_test.go

@@ -0,0 +1,41 @@
+package signerverifier
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLoadKeyFromSSLibBytes(t *testing.T) {
+	t.Run("RSA public key", func(t *testing.T) {
+		contents, err := os.ReadFile(filepath.Join("test-data", "rsa-test-key.pub"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		key, err := LoadKeyFromSSLibBytes(contents)
+		assert.Nil(t, err)
+
+		assert.Equal(t, "4e8d20af09fcaed6c388a186427f94a5f7ff5591ec295f4aab2cff49ffe39e9b", key.KeyID)
+		assert.Equal(t, "-----BEGIN PUBLIC KEY-----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\nEm53T13mZzYUvbLJ0q3aljZVLIC3IZn3ZwA2yCWchBkVAgMBAAE=\n-----END PUBLIC KEY-----", key.KeyVal.Public)
+		assert.Equal(t, RSAKeyScheme, key.Scheme)
+		assert.Equal(t, RSAKeyType, key.KeyType)
+	})
+
+	t.Run("RSA private key", func(t *testing.T) {
+		contents, err := os.ReadFile(filepath.Join("test-data", "rsa-test-key"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		key, err := LoadKeyFromSSLibBytes(contents)
+		assert.Nil(t, err)
+
+		assert.Equal(t, "4e8d20af09fcaed6c388a186427f94a5f7ff5591ec295f4aab2cff49ffe39e9b", key.KeyID)
+		assert.Equal(t, "-----BEGIN PUBLIC KEY-----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\nEm53T13mZzYUvbLJ0q3aljZVLIC3IZn3ZwA2yCWchBkVAgMBAAE=\n-----END PUBLIC KEY-----", key.KeyVal.Public)
+		expectedPrivateKey := "-----BEGIN RSA PRIVATE KEY-----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\nI+YQsJgrHE0TmYxxRkgeYUy7s5DoHE25rfvdy5Lx+xAOH8ZgD1SGOw==\n-----END RSA PRIVATE KEY-----"
+		assert.Equal(t, expectedPrivateKey, key.KeyVal.Private)
+		assert.Equal(t, RSAKeyScheme, key.Scheme)
+		assert.Equal(t, RSAKeyType, key.KeyType)
+	})
+}