Allow custom priv key bytes on all platforms

privkey/all.go

@@ -0,0 +1,54 @@
+package privkey
+
+import (
+	"errors"
+	"os"
+	"sync"
+)
+
+var keyBytesProvider = func(sshKeyPath *string) ([]byte, error) {
+	if sshKeyPath != nil {
+		key, err := os.ReadFile(*sshKeyPath)
+		if err != nil {
+			return nil, errors.New("unable to read private key: " + *sshKeyPath)
+		}
+		return key, nil
+	} else {
+		return nil, errors.New("unable to identify private key location (nil config)")
+	}
+}
+
+var providerMutex sync.RWMutex
+
+// GetBytes returns the SSH private key bytes.
+// On iOS, it calls the provider function that was set by the iOS app
+// using SetKeyBytesProvider or SetKeyBytes.
+func GetBytes(sshKeyPath *string) ([]byte, error) {
+	providerMutex.RLock()
+	provider := keyBytesProvider
+	providerMutex.RUnlock()
+
+	if provider == nil {
+		return nil, errors.New("key bytes provider not set - call SetKeyBytes first")
+	}
+
+	keyBytes, err := provider(sshKeyPath)
+	if err != nil {
+		return nil, errors.New("unable to get key bytes from provider: " + err.Error())
+	}
+
+	if len(keyBytes) == 0 {
+		return nil, errors.New("provider returned empty key bytes")
+	}
+
+	return keyBytes, nil
+}
+
+// SetBytes allows the iOS app to directly set the SSH key bytes.
+func SetBytes(keyBytes []byte) {
+	providerMutex.Lock()
+	defer providerMutex.Unlock()
+	keyBytesProvider = func(*string) ([]byte, error) {
+		return keyBytes, nil
+	}
+}