dnsdist: Handle EAGAIN in the GnuTLS DNS over TLS provider

[thirdparty/pdns.git] / pdns / dnsdistdist / tcpiohandler.cc

diff --git a/pdns/dnsdistdist/tcpiohandler.cc b/pdns/dnsdistdist/tcpiohandler.cc
index 1f516f14f11db0c5361e8831834338edd5110b36..2be4a4c62fe4675b13468dc0271b5f696c69f9bb 100644 (file)
--- a/pdns/dnsdistdist/tcpiohandler.cc
+++ b/pdns/dnsdistdist/tcpiohandler.cc
@@ -712,9 +712,17 @@ public:
       }
       else if (res < 0) {
         if (gnutls_error_is_fatal(res)) {
-          throw std::runtime_error("Error reading from TLS connection");
+          throw std::runtime_error("Error reading from TLS connection:" + std::string(gnutls_strerror(res)));
+        }
+        else if (res == GNUTLS_E_AGAIN) {
+          int result = waitForData(d_socket, readTimeout);
+          if (result <= 0) {
+            throw std::runtime_error("Error reading from TLS connection: " + std::to_string(result));
+          }
+        }
+        else {
+          vinfolog("Non-fatal error while reading from TLS connection: %s", gnutls_strerror(res));
         }
-        warnlog("Warning, non-fatal error while reading from TLS connection: %s", gnutls_strerror(res));
       }
 
       if (totalTimeout) {
@@ -746,9 +754,17 @@ public:
       }
       else if (res < 0) {
         if (gnutls_error_is_fatal(res)) {
-          throw std::runtime_error("Error writing to TLS connection");
+          throw std::runtime_error("Error writing to TLS connection: " + std::string(gnutls_strerror(res)));
+        }
+        else if (res == GNUTLS_E_AGAIN) {
+          int result = waitForRWData(d_socket, false, writeTimeout, 0);
+          if (result <= 0) {
+            throw std::runtime_error("Error waiting to write to TLS connection: " + std::to_string(result));
+          }
+        }
+        else {
+          vinfolog("Non-fatal error while writing to TLS connection: %s", gnutls_strerror(res));
         }
-        warnlog("Warning, non-fatal error while writing to TLS connection: %s", gnutls_strerror(res));
       }
     }
     while (got < bufferSize);