add openssl 1.1 support

changes:
  - CRYPTO_lock detection replaced in configure.ac. We don't use that
    function anywhere, so just replace it with the suggested one from
    https://wiki.openssl.org/index.php/Library_Initialization#Autoconf
  - OPENSSL_NO_SSL2 is no longer defined while ssl2 is not included.
    Set it ourself using the suggested openssl 1.1 version check from
    https://wiki.openssl.org/index.php/1.1_API_Changes#Backward_compatibility
  - openssl 1.1 sends a sigpipe if the connection is still open when
    calling SSL_shutdown(), so move the close before the shutdown.

Signed-off-by: Sven Nierlein <sven@nierlein.de>

1 files changed, 7 insertions, 0 deletions

diff --git a/plugins/common.h b/plugins/common.h
index 01003b3b..8719b502 100644
--- a/plugins/common.h
+++ b/plugins/common.h
@@ -161,6 +161,13 @@
 #  endif
 #endif
 
+/* openssl 1.1 does not set OPENSSL_NO_SSL2 by default but ships without ssl2 */
+#ifdef OPENSSL_VERSION_NUMBER
+#  if OPENSSL_VERSION_NUMBER >= 0x10100000
+#   define OPENSSL_NO_SSL2
+#  endif
+#endif
+
 /*
  *
  * Standard Values