Merge branch 'subsystems'

7 files changed, 278 insertions, 119 deletions

diff --git a/src/app/config/config.c b/src/app/config/config.c
index 81cc3e378f..45a23d67d5 100644
--- a/src/app/config/config.c
+++ b/src/app/config/config.c
@@ -64,6 +64,7 @@
 #include "app/config/confparse.h"
 #include "app/config/statefile.h"
 #include "app/main/main.h"
+#include "app/main/subsysmgr.h"
 #include "core/mainloop/connection.h"
 #include "core/mainloop/cpuworker.h"
 #include "core/mainloop/mainloop.h"
@@ -112,9 +113,9 @@
 #include "lib/crypt_ops/crypto_rand.h"
 #include "lib/crypt_ops/crypto_util.h"
 #include "lib/encoding/confline.h"
-#include "lib/log/git_revision.h"
 #include "lib/net/resolve.h"
 #include "lib/sandbox/sandbox.h"
+#include "lib/version/torversion.h"
 
 #ifdef ENABLE_NSS
 #include "lib/crypt_ops/crypto_nss_mgt.h"
@@ -972,42 +973,6 @@ set_options(or_options_t *new_val, char **msg)
   return 0;
 }
 
-/** The version of this Tor process, as parsed. */
-static char *the_tor_version = NULL;
-/** A shorter version of this Tor process's version, for export in our router
- *  descriptor.  (Does not include the git version, if any.) */
-static char *the_short_tor_version = NULL;
-
-/** Return the current Tor version. */
-const char *
-get_version(void)
-{
-  if (the_tor_version == NULL) {
-    if (strlen(tor_git_revision)) {
-      tor_asprintf(&the_tor_version, "%s (git-%s)", get_short_version(),
-                   tor_git_revision);
-    } else {
-      the_tor_version = tor_strdup(get_short_version());
-    }
-  }
-  return the_tor_version;
-}
-
-/** Return the current Tor version, without any git tag. */
-const char *
-get_short_version(void)
-{
-
-  if (the_short_tor_version == NULL) {
-#ifdef TOR_BUILD_TAG
-    tor_asprintf(&the_short_tor_version, "%s (%s)", VERSION, TOR_BUILD_TAG);
-#else
-    the_short_tor_version = tor_strdup(VERSION);
-#endif
-  }
-  return the_short_tor_version;
-}
-
 /** Release additional memory allocated in options
  */
 STATIC void
@@ -1067,9 +1032,6 @@ config_free_all(void)
   tor_free(torrc_defaults_fname);
   tor_free(global_dirfrontpagecontents);
 
-  tor_free(the_short_tor_version);
-  tor_free(the_tor_version);
-
   cleanup_protocol_warning_severity_level();
 
   have_parsed_cmdline = 0;
@@ -1432,10 +1394,10 @@ options_act_reversible(const or_options_t *old_options, char **msg)
    * processes. */
   if (running_tor && options->RunAsDaemon) {
     if (! start_daemon_has_been_called())
-      crypto_prefork();
+      subsystems_prefork();
     /* No need to roll back, since you can't change the value. */
     if (start_daemon())
-      crypto_postfork();
+      subsystems_postfork();
   }
 
 #ifdef HAVE_SYSTEMD
diff --git a/src/app/config/config.h b/src/app/config/config.h
index a169cfd451..4c497b83a6 100644
--- a/src/app/config/config.h
+++ b/src/app/config/config.h
@@ -41,8 +41,6 @@ const char *escaped_safe_str_client(const char *address);
 const char *escaped_safe_str(const char *address);
 void init_protocol_warning_severity_level(void);
 int get_protocol_warning_severity_level(void);
-const char *get_version(void);
-const char *get_short_version(void);
 
 /** An error from options_trial_assign() or options_init_from_string(). */
 typedef enum setopt_err_t {
diff --git a/src/app/config/statefile.c b/src/app/config/statefile.c
index 8a8b7ced01..4ba7be1519 100644
--- a/src/app/config/statefile.c
+++ b/src/app/config/statefile.c
@@ -45,6 +45,7 @@
 #include "app/config/statefile.h"
 #include "lib/encoding/confline.h"
 #include "lib/net/resolve.h"
+#include "lib/version/torversion.h"
 
 #include "app/config/or_state_st.h"
 
diff --git a/src/app/main/main.c b/src/app/main/main.c
index 04bbfadcb7..b8dcb852d2 100644
--- a/src/app/main/main.c
+++ b/src/app/main/main.c
@@ -15,6 +15,7 @@
 #include "app/config/statefile.h"
 #include "app/main/main.h"
 #include "app/main/ntmain.h"
+#include "app/main/subsysmgr.h"
 #include "core/mainloop/connection.h"
 #include "core/mainloop/cpuworker.h"
 #include "core/mainloop/mainloop.h"
@@ -69,7 +70,6 @@
 #include "lib/container/buffers.h"
 #include "lib/crypt_ops/crypto_rand.h"
 #include "lib/crypt_ops/crypto_s2k.h"
-#include "lib/err/backtrace.h"
 #include "lib/geoip/geoip.h"
 
 #include "lib/process/waitpid.h"
@@ -84,6 +84,7 @@
 #include "lib/encoding/confline.h"
 #include "lib/evloop/timers.h"
 #include "lib/crypt_ops/crypto_init.h"
+#include "lib/version/torversion.h"
 
 #include <event2/event.h>
 
@@ -427,18 +428,6 @@ dumpstats(int severity)
   rend_service_dump_stats(severity);
 }
 
-/** Called by exit() as we shut down the process.
- */
-static void
-exit_function(void)
-{
-  /* NOTE: If we ever daemonize, this gets called immediately.  That's
-   * okay for now, because we only use this on Windows.  */
-#ifdef _WIN32
-  WSACleanup();
-#endif
-}
-
 #ifdef _WIN32
 #define UNIX_ONLY 0
 #else
@@ -547,12 +536,6 @@ tor_init(int argc, char *argv[])
   tor_snprintf(progname, sizeof(progname), "Tor %s", get_version());
   log_set_application_name(progname);
 
-  /* Set up the crypto nice and early */
-  if (crypto_early_init() < 0) {
-    log_err(LD_GENERAL, "Unable to initialize the crypto subsystem!");
-    return -1;
-  }
-
   /* Initialize the history structures. */
   rep_hist_init();
   /* Initialize the service cache. */
@@ -632,12 +615,6 @@ tor_init(int argc, char *argv[])
   rust_log_welcome_string();
 #endif /* defined(HAVE_RUST) */
 
-  if (network_init()<0) {
-    log_err(LD_BUG,"Error initializing network; exiting.");
-    return -1;
-  }
-  atexit(exit_function);
-
   int init_rv = options_init_from_torrc(argc,argv);
   if (init_rv < 0) {
     log_err(LD_CONFIG,"Reading config failed--see warnings above.");
@@ -784,7 +761,6 @@ tor_free_all(int postfork)
   routerparse_free_all();
   ext_orport_free_all();
   control_free_all();
-  tor_free_getaddrinfo_cache();
   protover_free_all();
   bridges_free_all();
   consdiffmgr_free_all();
@@ -802,7 +778,6 @@ tor_free_all(int postfork)
     policies_free_all();
   }
   if (!postfork) {
-    tor_tls_free_all();
 #ifndef _WIN32
     tor_getpwnam(NULL);
 #endif
@@ -815,12 +790,12 @@ tor_free_all(int postfork)
     release_lockfile();
   }
   tor_libevent_free_all();
+
+  subsystems_shutdown();
+
   /* Stuff in util.c and address.c*/
   if (!postfork) {
-    escaped(NULL);
     esc_router_info(NULL);
-    clean_up_backtrace_handler();
-    logs_free_all(); /* free log strings. do this last so logs keep working. */
   }
 }
 
@@ -879,7 +854,6 @@ tor_cleanup(void)
                       later, if it makes shutdown unacceptably slow.  But for
                       now, leave it here: it's helped us catch bugs in the
                       past. */
-  crypto_global_cleanup();
 }
 
 /** Read/create keys as needed, and echo our fingerprint to stdout. */
@@ -1275,7 +1249,6 @@ static int
 run_tor_main_loop(void)
 {
   handle_signals();
-  monotime_init();
   timers_initialize();
   initialize_mainloop_events();
 
@@ -1387,54 +1360,13 @@ tor_run_main(const tor_main_configuration_t *tor_cfg)
 {
   int result = 0;
 
-#ifdef _WIN32
-#ifndef HeapEnableTerminationOnCorruption
-#define HeapEnableTerminationOnCorruption 1
-#endif
-  /* On heap corruption, just give up; don't try to play along. */
-  HeapSetInformation(NULL, HeapEnableTerminationOnCorruption, NULL, 0);
-
-  /* SetProcessDEPPolicy is only supported on 32-bit Windows.
-   * (On 64-bit Windows it always fails, and some compilers don't like the
-   * PSETDEP cast.)
-   * 32-bit Windows defines _WIN32.
-   * 64-bit Windows defines _WIN32 and _WIN64. */
-#ifndef _WIN64
-  /* Call SetProcessDEPPolicy to permanently enable DEP.
-     The function will not resolve on earlier versions of Windows,
-     and failure is not dangerous. */
-  HMODULE hMod = GetModuleHandleA("Kernel32.dll");
-  if (hMod) {
-    typedef BOOL (WINAPI *PSETDEP)(DWORD);
-    PSETDEP setdeppolicy = (PSETDEP)GetProcAddress(hMod,
-                           "SetProcessDEPPolicy");
-    if (setdeppolicy) {
-      /* PROCESS_DEP_ENABLE | PROCESS_DEP_DISABLE_ATL_THUNK_EMULATION */
-      setdeppolicy(3);
-    }
-  }
-#endif /* !defined(_WIN64) */
-#endif /* defined(_WIN32) */
-
-  {
-    int bt_err = configure_backtrace_handler(get_version());
-    if (bt_err < 0) {
-      log_warn(LD_BUG, "Unable to install backtrace handler: %s",
-               strerror(-bt_err));
-    }
-  }
-
 #ifdef EVENT_SET_MEM_FUNCTIONS_IMPLEMENTED
   event_set_mem_functions(tor_malloc_, tor_realloc_, tor_free_);
 #endif
 
-  init_protocol_warning_severity_level();
+  subsystems_init();
 
-  update_approx_time(time(NULL));
-  tor_threads_init();
-  tor_compress_init();
-  init_logging(0);
-  monotime_init();
+  init_protocol_warning_severity_level();
 
   int argc = tor_cfg->argc + tor_cfg->argc_owned;
   char **argv = tor_calloc(argc, sizeof(char*));
diff --git a/src/app/main/subsysmgr.c b/src/app/main/subsysmgr.c
new file mode 100644
index 0000000000..abd2edd10b
--- /dev/null
+++ b/src/app/main/subsysmgr.c
@@ -0,0 +1,202 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#include "orconfig.h"
+#include "app/main/subsysmgr.h"
+#include "lib/err/torerr.h"
+
+#include "lib/log/log.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/**
+ * True iff we have checked tor_subsystems for consistency.
+ **/
+static bool subsystem_array_validated = false;
+
+/**
+ * True if a given subsystem is initialized.  Expand this array if there
+ * are more than this number of subsystems.  (We'd rather not
+ * dynamically allocate in this module.)
+ **/
+static bool sys_initialized[128];
+
+/**
+ * Exit with a raw assertion if the subsystems list is inconsistent;
+ * initialize the subsystem_initialized array.
+ **/
+static void
+check_and_setup(void)
+{
+  if (subsystem_array_validated)
+    return;
+
+  raw_assert(ARRAY_LENGTH(sys_initialized) >= n_tor_subsystems);
+  memset(sys_initialized, 0, sizeof(sys_initialized));
+
+  int last_level = MIN_SUBSYS_LEVEL;
+
+  for (unsigned i = 0; i < n_tor_subsystems; ++i) {
+    const subsys_fns_t *sys = tor_subsystems[i];
+    if (sys->level < MIN_SUBSYS_LEVEL || sys->level > MAX_SUBSYS_LEVEL) {
+      fprintf(stderr, "BUG: Subsystem %s (at %u) has an invalid level %d. "
+              "It is supposed to be between %d and %d (inclusive).\n",
+              sys->name, i, sys->level, MIN_SUBSYS_LEVEL, MAX_SUBSYS_LEVEL);
+      raw_assert_unreached_msg("There is a bug in subsystem_list.c");
+    }
+    if (sys->level < last_level) {
+      fprintf(stderr, "BUG: Subsystem %s (at #%u) is in the wrong position. "
+              "Its level is %d; but the previous subsystem's level was %d.\n",
+              sys->name, i, sys->level, last_level);
+      raw_assert_unreached_msg("There is a bug in subsystem_list.c");
+    }
+    last_level = sys->level;
+  }
+
+  subsystem_array_validated = true;
+}
+
+/**
+ * Initialize all the subsystems; exit on failure.
+ **/
+int
+subsystems_init(void)
+{
+  return subsystems_init_upto(MAX_SUBSYS_LEVEL);
+}
+
+/**
+ * Initialize all the subsystems whose level is less than or equal to
+ * <b>target_level</b>; exit on failure.
+ **/
+int
+subsystems_init_upto(int target_level)
+{
+  check_and_setup();
+
+  for (unsigned i = 0; i < n_tor_subsystems; ++i) {
+    const subsys_fns_t *sys = tor_subsystems[i];
+    if (!sys->supported)
+      continue;
+    if (sys->level > target_level)
+      break;
+    if (sys_initialized[i])
+      continue;
+    int r = 0;
+    if (sys->initialize) {
+      // Note that the logging subsystem is designed so that it does no harm
+      // to log a message in an uninitialized state.  These messages will be
+      // discarded for now, however.
+      log_debug(LD_GENERAL, "Initializing %s", sys->name);
+      r = sys->initialize();
+    }
+    if (r < 0) {
+      fprintf(stderr, "BUG: subsystem %s (at %u) initialization failed.\n",
+              sys->name, i);
+      raw_assert_unreached_msg("A subsystem couldn't be initialized.");
+    }
+    sys_initialized[i] = true;
+  }
+
+  return 0;
+}
+
+/**
+ * Shut down all the subsystems.
+ **/
+void
+subsystems_shutdown(void)
+{
+  subsystems_shutdown_downto(MIN_SUBSYS_LEVEL - 1);
+}
+
+/**
+ * Shut down all the subsystems whose level is above <b>target_level</b>.
+ **/
+void
+subsystems_shutdown_downto(int target_level)
+{
+  check_and_setup();
+
+  for (int i = (int)n_tor_subsystems - 1; i >= 0; --i) {
+    const subsys_fns_t *sys = tor_subsystems[i];
+    if (!sys->supported)
+      continue;
+    if (sys->level <= target_level)
+      break;
+    if (! sys_initialized[i])
+      continue;
+    if (sys->shutdown) {
+      log_debug(LD_GENERAL, "Shutting down %s", sys->name);
+      sys->shutdown();
+    }
+    sys_initialized[i] = false;
+  }
+}
+
+/**
+ * Run pre-fork code on all subsystems that declare any
+ **/
+void
+subsystems_prefork(void)
+{
+  check_and_setup();
+
+  for (int i = (int)n_tor_subsystems - 1; i >= 0; --i) {
+    const subsys_fns_t *sys = tor_subsystems[i];
+    if (!sys->supported)
+      continue;
+    if (! sys_initialized[i])
+      continue;
+    if (sys->prefork) {
+      log_debug(LD_GENERAL, "Pre-fork: %s", sys->name);
+      sys->prefork();
+    }
+  }
+}
+
+/**
+ * Run post-fork code on all subsystems that declare any
+ **/
+void
+subsystems_postfork(void)
+{
+  check_and_setup();
+
+  for (unsigned i = 0; i < n_tor_subsystems; ++i) {
+    const subsys_fns_t *sys = tor_subsystems[i];
+    if (!sys->supported)
+      continue;
+    if (! sys_initialized[i])
+      continue;
+    if (sys->postfork) {
+      log_debug(LD_GENERAL, "Post-fork: %s", sys->name);
+      sys->postfork();
+    }
+  }
+}
+
+/**
+ * Run thread-cleanup code on all subsystems that declare any
+ **/
+void
+subsystems_thread_cleanup(void)
+{
+  check_and_setup();
+
+  for (int i = (int)n_tor_subsystems - 1; i >= 0; --i) {
+    const subsys_fns_t *sys = tor_subsystems[i];
+    if (!sys->supported)
+      continue;
+    if (! sys_initialized[i])
+      continue;
+    if (sys->thread_cleanup) {
+      log_debug(LD_GENERAL, "Thread cleanup: %s", sys->name);
+      sys->thread_cleanup();
+    }
+  }
+}
diff --git a/src/app/main/subsysmgr.h b/src/app/main/subsysmgr.h
new file mode 100644
index 0000000000..4b3cad62ad
--- /dev/null
+++ b/src/app/main/subsysmgr.h
@@ -0,0 +1,24 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_SUBSYSMGR_T
+#define TOR_SUBSYSMGR_T
+
+#include "lib/subsys/subsys.h"
+
+extern const struct subsys_fns_t *tor_subsystems[];
+extern const unsigned n_tor_subsystems;
+
+int subsystems_init(void);
+int subsystems_init_upto(int level);
+
+void subsystems_shutdown(void);
+void subsystems_shutdown_downto(int level);
+
+void subsystems_prefork(void);
+void subsystems_postfork(void);
+void subsystems_thread_cleanup(void);
+
+#endif
diff --git a/src/app/main/subsystem_list.c b/src/app/main/subsystem_list.c
new file mode 100644
index 0000000000..190e6579d8
--- /dev/null
+++ b/src/app/main/subsystem_list.c
@@ -0,0 +1,40 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#include "orconfig.h"
+#include "app/main/subsysmgr.h"
+#include "lib/cc/compat_compiler.h"
+#include "lib/cc/torint.h"
+
+#include "lib/compress/compress_sys.h"
+#include "lib/crypt_ops/crypto_sys.h"
+#include "lib/err/torerr_sys.h"
+#include "lib/log/log_sys.h"
+#include "lib/net/network_sys.h"
+#include "lib/process/winprocess_sys.h"
+#include "lib/thread/thread_sys.h"
+#include "lib/time/time_sys.h"
+#include "lib/tls/tortls_sys.h"
+#include "lib/wallclock/wallclock_sys.h"
+
+#include <stddef.h>
+
+/**
+ * Global list of the subsystems in Tor, in the order of their initialization.
+ **/
+const subsys_fns_t *tor_subsystems[] = {
+  &sys_winprocess, /* -100 */
+  &sys_torerr,
+  &sys_wallclock,
+  &sys_threads,
+  &sys_logging,
+  &sys_time,
+  &sys_network,
+  &sys_compress,
+  &sys_crypto,
+  &sys_tortls,
+};
+
+const unsigned n_tor_subsystems = ARRAY_LENGTH(tor_subsystems);