From 268a53f50de795481dd73ffd0e0c1339ad3dc44b Mon Sep 17 00:00:00 2001 From: Brandon Carpenter Date: Tue, 12 Sep 2017 08:21:52 -0700 Subject: io: Reply to ping frames Add an immediate ping reply (pong) to the outgoing stream when a ping is received. Unsolicited pongs are ignored. Signed-off-by: Brandon Carpenter Signed-off-by: Daniel P. Berrange --- io/channel-websock.c | 66 ++++++++++++++++++++++++++++++++++------------------ 1 file changed, 44 insertions(+), 22 deletions(-) (limited to 'io') diff --git a/io/channel-websock.c b/io/channel-websock.c index bfe4008d83..b6fc0c9b8e 100644 --- a/io/channel-websock.c +++ b/io/channel-websock.c @@ -573,7 +573,8 @@ static gboolean qio_channel_websock_handshake_io(QIOChannel *ioc, } -static void qio_channel_websock_encode(QIOChannelWebsock *ioc) +static void qio_channel_websock_encode_buffer(Buffer *output, + uint8_t opcode, Buffer *buffer) { size_t header_size; union { @@ -581,33 +582,37 @@ static void qio_channel_websock_encode(QIOChannelWebsock *ioc) QIOChannelWebsockHeader ws; } header; - if (!ioc->rawoutput.offset) { - return; - } - header.ws.b0 = QIO_CHANNEL_WEBSOCK_HEADER_FIELD_FIN | - (QIO_CHANNEL_WEBSOCK_OPCODE_BINARY_FRAME & - QIO_CHANNEL_WEBSOCK_HEADER_FIELD_OPCODE); - if (ioc->rawoutput.offset < - QIO_CHANNEL_WEBSOCK_PAYLOAD_LEN_THRESHOLD_7_BIT) { - header.ws.b1 = (uint8_t)ioc->rawoutput.offset; + (opcode & QIO_CHANNEL_WEBSOCK_HEADER_FIELD_OPCODE); + if (buffer->offset < QIO_CHANNEL_WEBSOCK_PAYLOAD_LEN_THRESHOLD_7_BIT) { + header.ws.b1 = (uint8_t)buffer->offset; header_size = QIO_CHANNEL_WEBSOCK_HEADER_LEN_7_BIT; - } else if (ioc->rawoutput.offset < + } else if (buffer->offset < QIO_CHANNEL_WEBSOCK_PAYLOAD_LEN_THRESHOLD_16_BIT) { header.ws.b1 = QIO_CHANNEL_WEBSOCK_PAYLOAD_LEN_MAGIC_16_BIT; - header.ws.u.s16.l16 = cpu_to_be16((uint16_t)ioc->rawoutput.offset); + header.ws.u.s16.l16 = cpu_to_be16((uint16_t)buffer->offset); header_size = QIO_CHANNEL_WEBSOCK_HEADER_LEN_16_BIT; } else { header.ws.b1 = QIO_CHANNEL_WEBSOCK_PAYLOAD_LEN_MAGIC_64_BIT; - header.ws.u.s64.l64 = cpu_to_be64(ioc->rawoutput.offset); + header.ws.u.s64.l64 = cpu_to_be64(buffer->offset); header_size = QIO_CHANNEL_WEBSOCK_HEADER_LEN_64_BIT; } header_size -= QIO_CHANNEL_WEBSOCK_HEADER_LEN_MASK; - buffer_reserve(&ioc->encoutput, header_size + ioc->rawoutput.offset); - buffer_append(&ioc->encoutput, header.buf, header_size); - buffer_append(&ioc->encoutput, ioc->rawoutput.buffer, - ioc->rawoutput.offset); + buffer_reserve(output, header_size + buffer->offset); + buffer_append(output, header.buf, header_size); + buffer_append(output, buffer->buffer, buffer->offset); +} + + +static void qio_channel_websock_encode(QIOChannelWebsock *ioc) +{ + if (!ioc->rawoutput.offset) { + return; + } + qio_channel_websock_encode_buffer( + &ioc->encoutput, QIO_CHANNEL_WEBSOCK_OPCODE_BINARY_FRAME, + &ioc->rawoutput); buffer_reset(&ioc->rawoutput); } @@ -652,7 +657,7 @@ static int qio_channel_websock_decode_header(QIOChannelWebsock *ioc, /* Websocket frame sanity check: * * Fragmentation is only supported for binary frames. * * All frames sent by a client MUST be masked. - * * Only binary encoding is supported. + * * Only binary and ping/pong encoding is supported. */ if (!fin) { if (opcode != QIO_CHANNEL_WEBSOCK_OPCODE_BINARY_FRAME) { @@ -713,6 +718,11 @@ static int qio_channel_websock_decode_payload(QIOChannelWebsock *ioc, * for purpose of unmasking, except at end of payload */ if (ioc->encinput.offset < ioc->payload_remain) { + /* Wait for the entire payload before processing control frames + * because the payload will most likely be echoed back. */ + if (ioc->opcode & QIO_CHANNEL_WEBSOCK_CONTROL_OPCODE_MASK) { + return QIO_CHANNEL_ERR_BLOCK; + } payload_len = ioc->encinput.offset - (ioc->encinput.offset % 4); } else { payload_len = ioc->payload_remain; @@ -735,13 +745,18 @@ static int qio_channel_websock_decode_payload(QIOChannelWebsock *ioc, } } - /* Drop the payload of ping/pong packets */ if (ioc->opcode == QIO_CHANNEL_WEBSOCK_OPCODE_BINARY_FRAME) { if (payload_len) { + /* binary frames are passed on */ buffer_reserve(&ioc->rawinput, payload_len); buffer_append(&ioc->rawinput, ioc->encinput.buffer, payload_len); } - } + } else if (ioc->opcode == QIO_CHANNEL_WEBSOCK_OPCODE_PING) { + /* ping frames produce an immediate reply */ + buffer_reset(&ioc->ping_reply); + qio_channel_websock_encode_buffer( + &ioc->ping_reply, QIO_CHANNEL_WEBSOCK_OPCODE_PONG, &ioc->encinput); + } /* pong frames are ignored */ if (payload_len) { buffer_advance(&ioc->encinput, payload_len); @@ -799,6 +814,7 @@ static void qio_channel_websock_finalize(Object *obj) buffer_free(&ioc->encoutput); buffer_free(&ioc->rawinput); buffer_free(&ioc->rawoutput); + buffer_free(&ioc->ping_reply); object_unref(OBJECT(ioc->master)); if (ioc->io_tag) { g_source_remove(ioc->io_tag); @@ -855,7 +871,13 @@ static ssize_t qio_channel_websock_write_wire(QIOChannelWebsock *ioc, { ssize_t ret; ssize_t done = 0; - qio_channel_websock_encode(ioc); + + /* ping replies take priority over binary data */ + if (!ioc->ping_reply.offset) { + qio_channel_websock_encode(ioc); + } else if (!ioc->encoutput.offset) { + buffer_move_empty(&ioc->encoutput, &ioc->ping_reply); + } while (ioc->encoutput.offset > 0) { ret = qio_channel_write(ioc->master, @@ -930,7 +952,7 @@ static void qio_channel_websock_set_watch(QIOChannelWebsock *ioc) return; } - if (ioc->encoutput.offset) { + if (ioc->encoutput.offset || ioc->ping_reply.offset) { cond |= G_IO_OUT; } if (ioc->encinput.offset < QIO_CHANNEL_WEBSOCK_MAX_BUFFER && -- cgit v1.2.1