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, 5 insertions, 3 deletions

diff --git a/plugins/check_smtp.c b/plugins/check_smtp.c
index 1996c6d3..f5a6fa3d 100644
--- a/plugins/check_smtp.c
+++ b/plugins/check_smtp.c
@@ -239,8 +239,8 @@ main (int argc, char **argv)
                   result = np_net_ssl_init(sd);
                   if(result != STATE_OK) {
                     printf (_("CRITICAL - Cannot create SSL context.\n"));
-                    np_net_ssl_cleanup();
                     close(sd);
+                    np_net_ssl_cleanup();
                     return STATE_CRITICAL;
                   } else {
                         ssl_established = 1;
@@ -764,10 +764,12 @@ recvlines(char *buf, size_t bufsize)
 int
 my_close (void)
 {
+        int result;
+        result = close(sd);
 #ifdef HAVE_SSL
-  np_net_ssl_cleanup();
+        np_net_ssl_cleanup();
 #endif
-  return close(sd);
+        return result;
 }