diff --git a/programs/ssl/dtls_server.c b/programs/ssl/dtls_server.c index 0a02694eb7..d1063cbe47 100644 --- a/programs/ssl/dtls_server.c +++ b/programs/ssl/dtls_server.c @@ -291,7 +291,14 @@ reset: ret = 0; goto reset; } else if (ret != 0) { - printf(" failed\n ! mbedtls_ssl_handshake returned -0x%x\n\n", (unsigned int) -ret); + printf(" failed\n ! mbedtls_ssl_handshake returned -0x%x\n", (unsigned int) -ret); + if (ret == MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE) { + printf(" An unexpected message was received from our peer. If this happened at\n"); + printf(" the beginning of the handshake, this is likely a duplicated packet or\n"); + printf(" a close_notify alert from the previous connection, which is harmless.\n"); + ret = 0; + } + printf("\n"); goto reset; }