security: tighten enum protection_level usage.

While changing Curl_sec_read_msg to accept an enum protection_level
instead of an int, I went ahead and fixed the usage of the associated
fields.

Some code was assuming that prot_clear == 0. Fixed those to use the
proper value. Added assertions prior to any code that would set the
protection level.

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/url.c b/lib/url.c
index fb5122d65..3f9bfa877 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -3541,6 +3541,10 @@ static struct connectdata *allocate_conn(struct SessionHandle *data)
      !conn->done_pipe)
     goto error;
 
+#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
+  conn->data_prot = prot_clear;
+#endif
+
   return conn;
   error:
   Curl_llist_destroy(conn->send_pipe, NULL);