File check_inv_ALPN_lists.patch of Package python3-pyOpenSSL.29613

From cc5c00ae5fd3c19d07fff79b5c4a08f5e58697ad Mon Sep 17 00:00:00 2001
From: "Nathaniel J. Smith" <njs@pobox.com>
Date: Wed, 27 Oct 2021 11:54:08 -0700
Subject: [PATCH 1/2] Check for invalid ALPN lists before calling OpenSSL, for
 consistency

Fixes gh-1043
---
 src/OpenSSL/SSL.py |   12 ++++++++++++
 tests/test_ssl.py  |    2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

--- a/src/OpenSSL/SSL.py
+++ b/src/OpenSSL/SSL.py
@@ -1423,6 +1423,12 @@ class Context(object):
             This list should be a Python list of bytestrings representing the
             protocols to offer, e.g. ``[b'http/1.1', b'spdy/2']``.
         """
+        # Different versions of OpenSSL are inconsistent about how they handle
+        # empty proto lists (see #1043), so we avoid the problem entirely by
+        # rejecting them ourselves.
+        if not protos:
+            raise ValueError("at least one protocol must be specified")
+
         # Take the list of protocols and join them together, prefixing them
         # with their lengths.
         protostr = b"".join(
@@ -2451,6 +2457,12 @@ class Connection(object):
             This list should be a Python list of bytestrings representing the
             protocols to offer, e.g. ``[b'http/1.1', b'spdy/2']``.
         """
+        # Different versions of OpenSSL are inconsistent about how they handle
+        # empty proto lists (see #1043), so we avoid the problem entirely by
+        # rejecting them ourselves.
+        if not protos:
+            raise ValueError("at least one protocol must be specified")
+
         # Take the list of protocols and join them together, prefixing them
         # with their lengths.
         protostr = b"".join(
--- a/tests/test_ssl.py
+++ b/tests/test_ssl.py
@@ -1934,7 +1934,7 @@ class TestApplicationLayerProtoNegotiati
         protocols list. Ensure that we produce a user-visible error.
         """
         context = Context(SSLv23_METHOD)
-        with pytest.raises(Error):
+        with pytest.raises(ValueError):
             context.set_alpn_protos([])
 
     def test_alpn_set_on_connection(self):