From: NIIBE Yutaka Date: Thu, 24 Aug 2023 16:07:26 +0900 Subject: [PATCH 01/12] agent: Add agent_kick_the_loop function. * agent/agent.h (agent_kick_the_loop): New. * agent/gpg-agent.c [HAVE_W32_SYSTEM] (the_event2): New. [HAVE_PSELECT_NO_EINTR] (event_pipe_fd): New. [!HAVE_PSELECT_NO_EINTR] (main_thread_pid): New. (create_an_event): New, factored out. (get_agent_daemon_notify_event): Use create_an_event. (handle_signal): Add a case for SIGCONT. (agent_kick_the_loop): New. (handle_connections): Call pselect possibly with the pipe. Call eselect with THE_EVENT2. -- GnuPG-bug-id: 6682 Signed-off-by: NIIBE Yutaka --- agent/agent.h | 1 + agent/gpg-agent.c | 150 +++++++++++++++++++++++++++++++++++++++++------------- 2 files changed, 117 insertions(+), 34 deletions(-) diff --git a/agent/agent.h b/agent/agent.h index 6a61f48..4578e18 100644 --- a/agent/agent.h +++ b/agent/agent.h @@ -428,6 +428,7 @@ void *get_agent_daemon_notify_event (void); #endif void agent_sighup_action (void); int map_pk_openpgp_to_gcry (int openpgp_algo); +void agent_kick_the_loop (void); /*-- command.c --*/ gpg_error_t agent_inq_pinentry_launched (ctrl_t ctrl, unsigned long pid, diff --git a/agent/gpg-agent.c b/agent/gpg-agent.c index 937af32..6cb67c1 100644 --- a/agent/gpg-agent.c +++ b/agent/gpg-agent.c @@ -435,6 +435,17 @@ static assuan_sock_nonce_t socket_nonce_ssh; * Let's try this as default. Change at runtime with --listen-backlog. */ static int listen_backlog = 64; +#ifdef HAVE_W32_SYSTEM +/* The event to break the select call. */ +static HANDLE the_event2; +#elif defined(HAVE_PSELECT_NO_EINTR) +/* An FD to break the select call. */ +static int event_pipe_fd; +#else +/* PID of the main thread. */ +static pid_t main_thread_pid; +#endif + /* Default values for options passed to the pinentry. */ static char *default_display; static char *default_ttyname; @@ -2145,39 +2156,45 @@ get_agent_active_connection_count (void) notification event. Calling it the first time creates that event. */ #if defined(HAVE_W32_SYSTEM) +static void * +create_an_event (void) +{ + HANDLE h, h2; + SECURITY_ATTRIBUTES sa = { sizeof (SECURITY_ATTRIBUTES), NULL, TRUE}; + + /* We need to use a manual reset event object due to the way our + w32-pth wait function works: If we would use an automatic + reset event we are not able to figure out which handle has + been signaled because at the time we single out the signaled + handles using WFSO the event has already been reset due to + the WFMO. */ + h = CreateEvent (&sa, TRUE, FALSE, NULL); + if (!h) + log_error ("can't create an event: %s\n", w32_strerror (-1) ); + else if (!DuplicateHandle (GetCurrentProcess(), h, + GetCurrentProcess(), &h2, + EVENT_MODIFY_STATE|SYNCHRONIZE, TRUE, 0)) + { + log_error ("setting synchronize for an event failed: %s\n", + w32_strerror (-1) ); + CloseHandle (h); + } + else + { + CloseHandle (h); + return h2; + } + + return INVALID_HANDLE_VALUE; +} + void * get_agent_daemon_notify_event (void) { static HANDLE the_event = INVALID_HANDLE_VALUE; if (the_event == INVALID_HANDLE_VALUE) - { - HANDLE h, h2; - SECURITY_ATTRIBUTES sa = { sizeof (SECURITY_ATTRIBUTES), NULL, TRUE}; - - /* We need to use a manual reset event object due to the way our - w32-pth wait function works: If we would use an automatic - reset event we are not able to figure out which handle has - been signaled because at the time we single out the signaled - handles using WFSO the event has already been reset due to - the WFMO. */ - h = CreateEvent (&sa, TRUE, FALSE, NULL); - if (!h) - log_error ("can't create scd notify event: %s\n", w32_strerror (-1) ); - else if (!DuplicateHandle (GetCurrentProcess(), h, - GetCurrentProcess(), &h2, - EVENT_MODIFY_STATE|SYNCHRONIZE, TRUE, 0)) - { - log_error ("setting synchronize for scd notify event failed: %s\n", - w32_strerror (-1) ); - CloseHandle (h); - } - else - { - CloseHandle (h); - the_event = h2; - } - } + the_event = create_an_event (); return the_event; } @@ -2543,6 +2560,11 @@ handle_signal (int signo) agent_sigusr2_action (); break; + case SIGCONT: + /* Do nothing, but break the syscall. */ + log_debug ("SIGCONT received - breaking select\n"); + break; + case SIGTERM: if (!shutdown_pending) log_info ("SIGTERM received - shutting down ...\n"); @@ -2974,6 +2996,28 @@ start_connection_thread_ssh (void *arg) } +void +agent_kick_the_loop (void) +{ + /* Kick the select loop. */ +#ifdef HAVE_W32_SYSTEM + int ret = SetEvent (the_event2); + if (ret == 0) + log_error ("SetEvent for agent_kick_the_loop failed: %s\n", + w32_strerror (-1)); +#else +# ifdef HAVE_PSELECT_NO_EINTR + write (event_pipe_fd, "", 1); +# else + int ret = kill (main_thread_pid, SIGCONT); + if (ret < 0) + log_error ("sending signal for agent_kick_the_loop failed: %s\n", + gpg_strerror (gpg_error_from_syserror ())); +# endif +#endif +} + + /* Connection handler loop. Wait for connection requests and spawn a thread after accepting a connection. */ static void @@ -2995,8 +3039,13 @@ handle_connections (gnupg_fd_t listen_fd, struct timespec curtime; struct timespec timeout; #ifdef HAVE_W32_SYSTEM - HANDLE events[2]; + HANDLE events[3]; unsigned int events_set; +#else + int signo; +# ifdef HAVE_PSELECT_NO_EINTR + int pipe_fd[2]; +# endif #endif int sock_inotify_fd = -1; int home_inotify_fd = -1; @@ -3024,11 +3073,24 @@ handle_connections (gnupg_fd_t listen_fd, npth_sigev_add (SIGUSR1); npth_sigev_add (SIGUSR2); npth_sigev_add (SIGINT); + npth_sigev_add (SIGCONT); npth_sigev_add (SIGTERM); npth_sigev_fini (); +# ifdef HAVE_PSELECT_NO_EINTR + ret = gnupg_create_pipe (pipe_fd); + if (ret) + { + log_error ("pipe creation failed: %s\n", gpg_strerror (ret)); + return; + } + event_pipe_fd = pipe_fd[1]; +# else + main_thread_pid = getpid (); +# endif #else events[0] = get_agent_daemon_notify_event (); - events[1] = INVALID_HANDLE_VALUE; + events[1] = the_event2 = create_an_event (); + events[2] = INVALID_HANDLE_VALUE; #endif if (disable_check_own_socket) @@ -3155,6 +3217,12 @@ handle_connections (gnupg_fd_t listen_fd, thus a simple assignment is fine to copy the entire set. */ read_fdset = fdset; +#ifdef HAVE_PSELECT_NO_EINTR + FD_SET (pipe_fd[0], &read_fdset); + if (nfd < pipe_fd[0]) + nfd = pipe_fd[0]; +#endif + npth_clock_gettime (&curtime); if (!(npth_timercmp (&curtime, &abstime, <))) { @@ -3170,11 +3238,8 @@ handle_connections (gnupg_fd_t listen_fd, npth_sigev_sigmask ()); saved_errno = errno; - { - int signo; - while (npth_sigev_get_pending (&signo)) - handle_signal (signo); - } + while (npth_sigev_get_pending (&signo)) + handle_signal (signo); #else ret = npth_eselect (nfd+1, &read_fdset, NULL, NULL, &timeout, events, &events_set); @@ -3197,6 +3262,15 @@ handle_connections (gnupg_fd_t listen_fd, next timeout. */ continue; +#ifdef HAVE_PSELECT_NO_EINTR + if (FD_ISSET (pipe_fd[0], &read_fdset)) + { + char buf[256]; + + read (pipe_fd[0], buf, sizeof buf); + } +#endif + /* The inotify fds are set even when a shutdown is pending (see * above). So we must handle them in any case. To avoid that * they trigger a second time we close them immediately. */ @@ -3274,6 +3348,14 @@ handle_connections (gnupg_fd_t listen_fd, close (sock_inotify_fd); if (home_inotify_fd != -1) close (home_inotify_fd); +#ifdef HAVE_W32_SYSTEM + if (the_event2 != INVALID_HANDLE_VALUE) + CloseHandle (the_event2); +#endif +#ifdef HAVE_PSELECT_NO_EINTR + close (pipe_fd[0]); + close (pipe_fd[1]); +#endif cleanup (); log_info (_("%s %s stopped\n"), gpgrt_strusage(11), gpgrt_strusage(13)); npth_attr_destroy (&tattr);