1 files changed, 372 insertions, 0 deletions
diff --git a/src/test/test_oom.c b/src/test/test_oom.c
new file mode 100644
index 000000000..32f4803bb
--- /dev/null
+++ b/src/test/test_oom.c
@@ -0,0 +1,372 @@
+/* Copyright (c) 2014, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/* Unit tests for OOM handling logic */
+
+#define RELAY_PRIVATE
+#define BUFFERS_PRIVATE
+#define CIRCUITLIST_PRIVATE
+#define CONNECTION_PRIVATE
+#include "or.h"
+#include "buffers.h"
+#include "circuitlist.h"
+#include "compat_libevent.h"
+#include "connection.h"
+#include "config.h"
+#ifdef ENABLE_MEMPOOLS
+#include "mempool.h"
+#endif
+#include "relay.h"
+#include "test.h"
+
+/* small replacement mock for circuit_mark_for_close_ to avoid doing all
+ * the other bookkeeping that comes with marking circuits. */
+static void
+circuit_mark_for_close_dummy_(circuit_t *circ, int reason, int line,
+                              const char *file)
+{
+  (void) reason;
+  if (circ->marked_for_close) {
+    TT_FAIL(("Circuit already marked for close at %s:%d, but we are marking "
+             "it again at %s:%d",
+             circ->marked_for_close_file, (int)circ->marked_for_close,
+             file, line));
+  }
+
+  circ->marked_for_close = line;
+  circ->marked_for_close_file = file;
+}
+
+static circuit_t *
+dummy_or_circuit_new(int n_p_cells, int n_n_cells)
+{
+  or_circuit_t *circ = or_circuit_new(0, NULL);
+  int i;
+  cell_t cell;
+
+  for (i=0; i < n_p_cells; ++i) {
+    crypto_rand((void*)&cell, sizeof(cell));
+    cell_queue_append_packed_copy(TO_CIRCUIT(circ), &circ->p_chan_cells,
+                                  0, &cell, 1, 0);
+  }
+
+  for (i=0; i < n_n_cells; ++i) {
+    crypto_rand((void*)&cell, sizeof(cell));
+    cell_queue_append_packed_copy(TO_CIRCUIT(circ),
+                                  &TO_CIRCUIT(circ)->n_chan_cells,
+                                  1, &cell, 1, 0);
+  }
+
+  TO_CIRCUIT(circ)->purpose = CIRCUIT_PURPOSE_OR;
+  return TO_CIRCUIT(circ);
+}
+
+static circuit_t *
+dummy_origin_circuit_new(int n_cells)
+{
+  origin_circuit_t *circ = origin_circuit_new();
+  int i;
+  cell_t cell;
+
+  for (i=0; i < n_cells; ++i) {
+    crypto_rand((void*)&cell, sizeof(cell));
+    cell_queue_append_packed_copy(TO_CIRCUIT(circ),
+                                  &TO_CIRCUIT(circ)->n_chan_cells,
+                                  1, &cell, 1, 0);
+  }
+
+  TO_CIRCUIT(circ)->purpose = CIRCUIT_PURPOSE_C_GENERAL;
+  return TO_CIRCUIT(circ);
+}
+
+static void
+add_bytes_to_buf(generic_buffer_t *buf, size_t n_bytes)
+{
+  char b[3000];
+
+  while (n_bytes) {
+    size_t this_add = n_bytes > sizeof(b) ? sizeof(b) : n_bytes;
+    crypto_rand(b, this_add);
+    generic_buffer_add(buf, b, this_add);
+    n_bytes -= this_add;
+  }
+}
+
+static edge_connection_t *
+dummy_edge_conn_new(circuit_t *circ,
+                    int type, size_t in_bytes, size_t out_bytes)
+{
+  edge_connection_t *conn;
+
+  if (type == CONN_TYPE_EXIT)
+    conn = edge_connection_new(type, AF_INET);
+  else
+    conn = ENTRY_TO_EDGE_CONN(entry_connection_new(type, AF_INET));
+
+  /* We add these bytes directly to the buffers, to avoid all the
+   * edge connection read/write machinery. */
+  add_bytes_to_buf(TO_CONN(conn)->inbuf, in_bytes);
+  add_bytes_to_buf(TO_CONN(conn)->outbuf, out_bytes);
+
+  conn->on_circuit = circ;
+  if (type == CONN_TYPE_EXIT) {
+    or_circuit_t *oc  = TO_OR_CIRCUIT(circ);
+    conn->next_stream = oc->n_streams;
+    oc->n_streams = conn;
+  } else {
+    origin_circuit_t *oc = TO_ORIGIN_CIRCUIT(circ);
+    conn->next_stream = oc->p_streams;
+    oc->p_streams = conn;
+  }
+
+  return conn;
+}
+
+/** Run unit tests for buffers.c */
+static void
+test_oom_circbuf(void *arg)
+{
+  or_options_t *options = get_options_mutable();
+  circuit_t *c1 = NULL, *c2 = NULL, *c3 = NULL, *c4 = NULL;
+  struct timeval tv = { 1389631048, 0 };
+
+  (void) arg;
+
+  MOCK(circuit_mark_for_close_, circuit_mark_for_close_dummy_);
+
+#ifdef ENABLE_MEMPOOLS
+  init_cell_pool();
+#endif /* ENABLE_MEMPOOLS */
+
+  /* Far too low for real life. */
+  options->MaxMemInQueues = 256*packed_cell_mem_cost();
+  options->CellStatistics = 0;
+
+  tt_int_op(cell_queues_check_size(), ==, 0); /* We don't start out OOM. */
+  tt_int_op(cell_queues_get_total_allocation(), ==, 0);
+  tt_int_op(buf_get_total_allocation(), ==, 0);
+
+  /* Now we're going to fake up some circuits and get them added to the global
+     circuit list. */
+  tv.tv_usec = 0;
+  tor_gettimeofday_cache_set(&tv);
+  c1 = dummy_origin_circuit_new(30);
+  tv.tv_usec = 10*1000;
+  tor_gettimeofday_cache_set(&tv);
+  c2 = dummy_or_circuit_new(20, 20);
+
+#ifdef ENABLE_MEMPOOLS
+  tt_int_op(packed_cell_mem_cost(), ==,
+            sizeof(packed_cell_t) + MP_POOL_ITEM_OVERHEAD);
+#else
+  tt_int_op(packed_cell_mem_cost(), ==,
+            sizeof(packed_cell_t));
+#endif /* ENABLE_MEMPOOLS */
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * 70);
+  tt_int_op(cell_queues_check_size(), ==, 0); /* We are still not OOM */
+
+  tv.tv_usec = 20*1000;
+  tor_gettimeofday_cache_set(&tv);
+  c3 = dummy_or_circuit_new(100, 85);
+  tt_int_op(cell_queues_check_size(), ==, 0); /* We are still not OOM */
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * 255);
+
+  tv.tv_usec = 30*1000;
+  tor_gettimeofday_cache_set(&tv);
+  /* Adding this cell will trigger our OOM handler. */
+  c4 = dummy_or_circuit_new(2, 0);
+
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * 257);
+
+  tt_int_op(cell_queues_check_size(), ==, 1); /* We are now OOM */
+
+  tt_assert(c1->marked_for_close);
+  tt_assert(! c2->marked_for_close);
+  tt_assert(! c3->marked_for_close);
+  tt_assert(! c4->marked_for_close);
+
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * (257 - 30));
+
+  circuit_free(c1);
+  tv.tv_usec = 0;
+  tor_gettimeofday_cache_set(&tv); /* go back in time */
+  c1 = dummy_or_circuit_new(90, 0);
+
+  tv.tv_usec = 40*1000; /* go back to the future */
+  tor_gettimeofday_cache_set(&tv);
+
+  tt_int_op(cell_queues_check_size(), ==, 1); /* We are now OOM */
+
+  tt_assert(c1->marked_for_close);
+  tt_assert(! c2->marked_for_close);
+  tt_assert(! c3->marked_for_close);
+  tt_assert(! c4->marked_for_close);
+
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * (257 - 30));
+
+ done:
+  circuit_free(c1);
+  circuit_free(c2);
+  circuit_free(c3);
+  circuit_free(c4);
+
+  UNMOCK(circuit_mark_for_close_);
+}
+
+/** Run unit tests for buffers.c */
+static void
+test_oom_streambuf(void *arg)
+{
+  or_options_t *options = get_options_mutable();
+  circuit_t *c1 = NULL, *c2 = NULL, *c3 = NULL, *c4 = NULL, *c5 = NULL;
+  struct timeval tv = { 1389641159, 0 };
+  uint32_t tvms;
+  int i;
+  smartlist_t *edgeconns = smartlist_new();
+
+  (void) arg;
+
+  MOCK(circuit_mark_for_close_, circuit_mark_for_close_dummy_);
+
+#ifdef ENABLE_MEMPOOLS
+  init_cell_pool();
+#endif /* ENABLE_MEMPOOLS */
+
+  /* Far too low for real life. */
+  options->MaxMemInQueues = 81*packed_cell_mem_cost() + 4096 * 34;
+  options->CellStatistics = 0;
+
+  tt_int_op(cell_queues_check_size(), ==, 0); /* We don't start out OOM. */
+  tt_int_op(cell_queues_get_total_allocation(), ==, 0);
+  tt_int_op(buf_get_total_allocation(), ==, 0);
+
+  /* Start all circuits with a bit of data queued in cells */
+  tv.tv_usec = 500*1000; /* go halfway into the second. */
+  tor_gettimeofday_cache_set(&tv);
+  c1 = dummy_or_circuit_new(10,10);
+  tv.tv_usec = 510*1000;
+  tor_gettimeofday_cache_set(&tv);
+  c2 = dummy_origin_circuit_new(20);
+  tv.tv_usec = 520*1000;
+  tor_gettimeofday_cache_set(&tv);
+  c3 = dummy_or_circuit_new(20,20);
+  tv.tv_usec = 530*1000;
+  tor_gettimeofday_cache_set(&tv);
+  c4 = dummy_or_circuit_new(0,0);
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * 80);
+
+  tv.tv_usec = 600*1000;
+  tor_gettimeofday_cache_set(&tv);
+
+  /* Add some connections to c1...c4. */
+  for (i = 0; i < 4; ++i) {
+    edge_connection_t *ec;
+    /* link it to a circuit */
+    tv.tv_usec += 10*1000;
+    tor_gettimeofday_cache_set(&tv);
+    ec = dummy_edge_conn_new(c1, CONN_TYPE_EXIT, 1000, 1000);
+    tt_assert(ec);
+    smartlist_add(edgeconns, ec);
+    tv.tv_usec += 10*1000;
+    tor_gettimeofday_cache_set(&tv);
+    ec = dummy_edge_conn_new(c2, CONN_TYPE_AP, 1000, 1000);
+    tt_assert(ec);
+    smartlist_add(edgeconns, ec);
+    tv.tv_usec += 10*1000;
+    tor_gettimeofday_cache_set(&tv);
+    ec = dummy_edge_conn_new(c4, CONN_TYPE_EXIT, 1000, 1000); /* Yes, 4 twice*/
+    tt_assert(ec);
+    smartlist_add(edgeconns, ec);
+    tv.tv_usec += 10*1000;
+    tor_gettimeofday_cache_set(&tv);
+    ec = dummy_edge_conn_new(c4, CONN_TYPE_EXIT, 1000, 1000);
+    smartlist_add(edgeconns, ec);
+    tt_assert(ec);
+  }
+
+  tv.tv_sec += 1;
+  tv.tv_usec = 0;
+  tvms = (uint32_t) tv_to_msec(&tv);
+
+  tt_int_op(circuit_max_queued_cell_age(c1, tvms), ==, 500);
+  tt_int_op(circuit_max_queued_cell_age(c2, tvms), ==, 490);
+  tt_int_op(circuit_max_queued_cell_age(c3, tvms), ==, 480);
+  tt_int_op(circuit_max_queued_cell_age(c4, tvms), ==, 0);
+
+  tt_int_op(circuit_max_queued_data_age(c1, tvms), ==, 390);
+  tt_int_op(circuit_max_queued_data_age(c2, tvms), ==, 380);
+  tt_int_op(circuit_max_queued_data_age(c3, tvms), ==, 0);
+  tt_int_op(circuit_max_queued_data_age(c4, tvms), ==, 370);
+
+  tt_int_op(circuit_max_queued_item_age(c1, tvms), ==, 500);
+  tt_int_op(circuit_max_queued_item_age(c2, tvms), ==, 490);
+  tt_int_op(circuit_max_queued_item_age(c3, tvms), ==, 480);
+  tt_int_op(circuit_max_queued_item_age(c4, tvms), ==, 370);
+
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * 80);
+  tt_int_op(buf_get_total_allocation(), ==, 4096*16*2);
+
+  /* Now give c4 a very old buffer of modest size */
+  {
+    edge_connection_t *ec;
+    tv.tv_sec -= 1;
+    tv.tv_usec = 0;
+    tor_gettimeofday_cache_set(&tv);
+    ec = dummy_edge_conn_new(c4, CONN_TYPE_EXIT, 1000, 1000);
+    tt_assert(ec);
+    smartlist_add(edgeconns, ec);
+  }
+  tt_int_op(buf_get_total_allocation(), ==, 4096*17*2);
+  tt_int_op(circuit_max_queued_item_age(c4, tvms), ==, 1000);
+
+  tt_int_op(cell_queues_check_size(), ==, 0);
+
+  /* And run over the limit. */
+  tv.tv_usec = 800*1000;
+  tor_gettimeofday_cache_set(&tv);
+  c5 = dummy_or_circuit_new(0,5);
+
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * 85);
+  tt_int_op(buf_get_total_allocation(), ==, 4096*17*2);
+
+  tt_int_op(cell_queues_check_size(), ==, 1); /* We are now OOM */
+
+  /* C4 should have died. */
+  tt_assert(! c1->marked_for_close);
+  tt_assert(! c2->marked_for_close);
+  tt_assert(! c3->marked_for_close);
+  tt_assert(c4->marked_for_close);
+  tt_assert(! c5->marked_for_close);
+
+  tt_int_op(cell_queues_get_total_allocation(), ==,
+            packed_cell_mem_cost() * 85);
+  tt_int_op(buf_get_total_allocation(), ==, 4096*8*2);
+
+ done:
+  circuit_free(c1);
+  circuit_free(c2);
+  circuit_free(c3);
+  circuit_free(c4);
+  circuit_free(c5);
+
+  SMARTLIST_FOREACH(edgeconns, edge_connection_t *, ec,
+                    connection_free_(TO_CONN(ec)));
+  smartlist_free(edgeconns);
+
+  UNMOCK(circuit_mark_for_close_);
+}
+
+struct testcase_t oom_tests[] = {
+  { "circbuf", test_oom_circbuf, TT_FORK, NULL, NULL },
+  { "streambuf", test_oom_streambuf, TT_FORK, NULL, NULL },
+  END_OF_TESTCASES
+};
+