commit 8e38791baf48ca2a4c865f3b7fc264392e63f426 Author: David Goulet <dgoulet@torproject.org> Date: Fri Jan 11 11:36:08 2019 -0500 sendme: Add helper functions for DATA cell packaging When we are about to send a DATA cell, we have to decrement the package window for both the circuit and stream level. This commit adds helper functions to handle the package window decrement. Part of #26288 Signed-off-by: David Goulet <dgoulet@torproject.org> --- src/core/or/relay.c | 16 +++++++++------- src/core/or/sendme.c | 37 +++++++++++++++++++++++++++++++++++++ src/core/or/sendme.h | 4 ++++ 3 files changed, 50 insertions(+), 7 deletions(-) diff --git a/src/core/or/relay.c b/src/core/or/relay.c index 0eb2ba3f6..06e201f20 100644 --- a/src/core/or/relay.c +++ b/src/core/or/relay.c @@ -2062,15 +2062,17 @@ connection_edge_package_raw_inbuf(edge_connection_t *conn, int package_partial, return 0; } - if (!cpath_layer) { /* non-rendezvous exit */ - tor_assert(circ->package_window > 0); - circ->package_window--; - } else { /* we're an AP, or an exit on a rendezvous circ */ - tor_assert(cpath_layer->package_window > 0); - cpath_layer->package_window--; + /* Handle the circuit-level SENDME package window. */ + if (sendme_circuit_data_packaged(circ, cpath_layer) < 0) { + /* Package window has gone under 0. Protocol issue. */ + log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, + "Circuit package window is below 0. Closing circuit."); + conn->end_reason = END_STREAM_REASON_TORPROTOCOL; + return -1; } - if (--conn->package_window <= 0) { /* is it 0 after decrement? */ + /* Handle the stream-level SENDME package window. */ + if (sendme_stream_data_packaged(conn) < 0) { connection_stop_reading(TO_CONN(conn)); log_debug(domain,"conn->package_window reached 0."); circuit_consider_stop_edge_reading(circ, cpath_layer); diff --git a/src/core/or/sendme.c b/src/core/or/sendme.c index 6d9f6f7d0..d7feb6bfc 100644 --- a/src/core/or/sendme.c +++ b/src/core/or/sendme.c @@ -213,3 +213,40 @@ sendme_stream_data_received(edge_connection_t *conn) tor_assert(conn); return --conn->deliver_window; } + +/* Called when a relay DATA cell is packaged on the given circuit. If + * layer_hint is NULL, this means we are the Exit end point else we are the + * Client. Update the package window and return its new value. */ +int +sendme_circuit_data_packaged(circuit_t *circ, crypt_path_t *layer_hint) +{ + int package_window, domain; + + tor_assert(circ); + + if (CIRCUIT_IS_ORIGIN(circ)) { + /* Client side. */ + tor_assert(layer_hint); + --layer_hint->package_window; + package_window = layer_hint->package_window; + domain = LD_APP; + } else { + /* Exit side. */ + tor_assert(!layer_hint); + --circ->package_window; + package_window = circ->package_window; + domain = LD_EXIT; + } + + log_debug(domain, "Circuit package_window now %d.", package_window); + return package_window; +} + +/* Called when a relay DATA cell is packaged for the given edge connection + * conn. Update the package window and return its new value. */ +int +sendme_stream_data_packaged(edge_connection_t *conn) +{ + tor_assert(conn); + return --conn->package_window; +} diff --git a/src/core/or/sendme.h b/src/core/or/sendme.h index 6313e9121..f50ccfbfe 100644 --- a/src/core/or/sendme.h +++ b/src/core/or/sendme.h @@ -28,4 +28,8 @@ int sendme_process_stream_level(edge_connection_t *conn, circuit_t *circ, int sendme_stream_data_received(edge_connection_t *conn); int sendme_circuit_data_received(circuit_t *circ, crypt_path_t *layer_hint); +/* Update package window functions. */ +int sendme_circuit_data_packaged(circuit_t *circ, crypt_path_t *layer_hint); +int sendme_stream_data_packaged(edge_connection_t *conn); + #endif /* !defined(TOR_SENDME_H) */