Don't require SSL_OP_IGNORE_UNEXPECTED_EOF.

Author: BonnyAD9

src/plugins/input/tcp/src/tls/DecoderFactory.cpp

@@ -12,6 +12,11 @@
 
 #include "TlsDecoder.hpp"
 
+// OpenSSL v1.1.1 compatibility
+#ifndef SSL_OP_IGNORE_UNEXPECTED_EOF
+#define SSL_OP_IGNORE_UNEXPECTED_EOF 0
+#endif // ifndef SSL_OP_IGNORE_UNEXPECTED_EOF
+
 namespace tcp_in {
 namespace tls {
 

src/plugins/input/tcp/src/tls/Ssl.cpp

@@ -36,6 +36,8 @@ ReadResult Ssl::read_ex(std::uint8_t *data, std::size_t &length) {
         auto err = SSL_get_error(get(), ret);
         length = 0;
         switch (err) {
+            case SSL_ERROR_SSL:
+                // The TLS connection is broken.
             case SSL_ERROR_ZERO_RETURN:
                 // Don't bother properly closing the connection. We only care about the received
                 // data but there will be no more data. Peer will handle this.