commit 20f802ea3cd5d8b3993a101da03dfec95bc9049e Author: Nick Mathewson <nickm@torproject.org> Date: Fri Dec 15 12:48:29 2017 -0500 Add an option to disable signal handler installation. Closes ticket 24588. --- changes/ticket24588 | 5 +++++ src/or/config.c | 7 +++++++ src/or/main.c | 4 +++- src/or/or.h | 5 +++++ 4 files changed, 20 insertions(+), 1 deletion(-) diff --git a/changes/ticket24588 b/changes/ticket24588 new file mode 100644 index 000000000..e64872d74 --- /dev/null +++ b/changes/ticket24588 @@ -0,0 +1,5 @@ + o Minor features (embedding, mobile): + - Applications that want to embed Tor can now tell Tor not to register + any of its own POSIX signal handlers, using the __DisableSignalHandlers + option. This option is not meant for general use. Closes ticket 24588. + diff --git a/src/or/config.c b/src/or/config.c index 016d87f81..ebbe726c7 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -564,6 +564,7 @@ static config_var_t option_vars_[] = { VAR("__ReloadTorrcOnSIGHUP", BOOL, ReloadTorrcOnSIGHUP, "1"), VAR("__AllDirActionsPrivate", BOOL, AllDirActionsPrivate, "0"), VAR("__DisablePredictedCircuits",BOOL,DisablePredictedCircuits, "0"), + VAR("__DisableSignalHandlers", BOOL, DisableSignalHandlers, "0"), VAR("__LeaveStreamsUnattached",BOOL, LeaveStreamsUnattached, "0"), VAR("__HashedControlSessionPassword", LINELIST, HashedControlSessionPassword, NULL), @@ -4652,6 +4653,12 @@ options_transition_allowed(const or_options_t *old, return -1; } + if (old->DisableSignalHandlers != new_val->DisableSignalHandlers) { + *msg = tor_strdup("While Tor is running, changing DisableSignalHandlers " + "is not allowed."); + return -1; + } + if (strcmp(old->DataDirectory,new_val->DataDirectory)!=0) { tor_asprintf(msg, "While Tor is running, changing DataDirectory " diff --git a/src/or/main.c b/src/or/main.c index 38f25cae5..9adad0794 100644 --- a/src/or/main.c +++ b/src/or/main.c @@ -3057,8 +3057,10 @@ void handle_signals(void) { int i; + const int enabled = !get_options()->DisableSignalHandlers; + for (i = 0; signal_handlers[i].signal_value >= 0; ++i) { - if (signal_handlers[i].try_to_register) { + if (enabled && signal_handlers[i].try_to_register) { signal_handlers[i].signal_event = tor_evsignal_new(tor_libevent_get_base(), signal_handlers[i].signal_value, diff --git a/src/or/or.h b/src/or/or.h index 9c5394987..91d643638 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -4651,6 +4651,11 @@ typedef struct { /** List of files that were opened by %include in torrc and torrc-defaults */ smartlist_t *FilesOpenedByIncludes; + + /** If true, Tor shouldn't install any posix signal handlers, since it is + * running embedded inside another process. + */ + int DisableSignalHandlers; } or_options_t; #define LOG_PROTOCOL_WARN (get_protocol_warning_severity_level())