Merge branch '2.10' into 2.11

paramiko/pkey.py

@@ -324,6 +324,8 @@
 
     def _read_private_key(self, tag, f, password=None):
         lines = f.readlines()
+        if not lines:
+            raise SSHException("no lines in {} private key file".format(tag))
 
         # find the BEGIN tag
         start = 0

sites/www/changelog.rst

@@ -2,6 +2,10 @@
 Changelog
 =========
 
+- bug:`1637` (via :issue:`1599`) Raise `SSHException` explicitly when blank
+  private key data is loaded, instead of the natural result of ``IndexError``.
+  This should help more bits of Paramiko or Paramiko-adjacent codebases to
+  correctly handle this class of error. Credit: Nicholas Dietz.
 - :release:`2.11.0 <2022-05-16>`
 - :release:`2.10.5 <2022-05-16>`
 - :release:`2.9.5 <2022-05-16>`

tests/test_pkey.py

@@ -186,6 +186,11 @@
                 with pytest.raises(SSHException, match=str(exception)):
                     RSAKey.from_private_key_file(_support("test_rsa.key"))
 
+    def test_loading_empty_keys_errors_usefully(self):
+        # #1599 - raise SSHException instead of IndexError
+        with pytest.raises(SSHException, match="no lines"):
+            RSAKey.from_private_key_file(_support("blank_rsa.key"))
+
     def test_load_rsa_password(self):
         key = RSAKey.from_private_key_file(
             _support("test_rsa_password.key"), "television"