/*- * Copyright (c) 2015 * Cryptonector LLC. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Cryptonector LLC may not be used to endorse or promote products * derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #ifdef WIN32 #include #include #else #include #endif #include "roken.h" #ifdef WIN32 #define dup2 _dup2 #endif static int pipefds[2] = {-1, -1}; ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL roken_detach_prep(int argc, char **argv, char *special_arg) { ssize_t bytes; size_t i; pid_t child; char **new_argv; char buf[1]; char fildes[21]; int status; pipefds[0] = -1; pipefds[1] = -1; #ifdef WIN32 if (_pipe(pipefds, 4, _O_NOINHERIT | O_BINARY) == -1) err(1, "failed to setup to detach daemon (_pipe failed)"); #else if (pipe(pipefds) == -1) err(1, "failed to setup to detach daemon (pipe failed)"); #endif new_argv = calloc(argc + 3, sizeof(*new_argv)); if (new_argv == NULL) err(1, "Out of memory"); #ifdef WIN32 pipefds[1] = _dup(pipefds[1]); /* The new fd will be inherited */ if (pipefds[1] == -1) err(1, "Out of memory"); #else (void) fcntl(pipefds[1], F_SETFD, fcntl(pipefds[1], F_GETFD & ~(O_CLOEXEC))); #endif if (snprintf(fildes, sizeof(fildes), "%d", pipefds[1]) >= sizeof(fildes)) err(1, "failed to setup to detach daemon (fd number %d too large)", pipefds[1]); new_argv[0] = argv[0]; new_argv[1] = special_arg; new_argv[2] = fildes; for (i = 1; argv[i] != NULL; i++) new_argv[i + 2] = argv[i]; new_argv[argc + 2] = NULL; #ifndef WIN32 fflush(stdout); child = fork(); #else { intptr_t child_handle; _flushall(); child_handle = spawnvp(_P_NOWAIT, argv[0], new_argv); if (child_handle == -1) child = (pid_t)-1; else child = GetProcessId((HANDLE)child_handle); } #endif if (child == (pid_t)-1) err(1, "failed to setup to fork daemon (fork failed)"); #ifndef WIN32 if (child == 0) { int fd; (void) close(pipefds[0]); pipefds[0] = -1; /* * Keep stdout/stderr for now so output and errors prior to * detach_finish() can be seen by the user. */ fd = open(_PATH_DEVNULL, O_RDWR, 0); if (fd == -1) err(1, "failed to open /dev/null"); (void) dup2(fd, STDIN_FILENO); if (fd > STDERR_FILENO) (void) close(fd); if (getenv("ROKEN_DETACH_USE_EXEC")) { (void) execvp(argv[0], new_argv); err(1, "failed to self-re-exec"); } free(new_argv); return pipefds[1]; } #endif /* Parent */ free(new_argv); (void) close(pipefds[1]); pipefds[1] = -1; do { bytes = read(pipefds[0], buf, sizeof(buf)); } while (bytes == -1 && errno == EINTR); (void) close(pipefds[0]); pipefds[0] = -1; if (bytes == -1) { /* * No need to wait for the process. We've killed it. If it * doesn't want to exit, we'd have to wait potentially forever, * but we want to indicate failure to the user as soon as * possible. A wait with timeout would end the same way * (attempting to kill the process). */ err(1, "failed to setup daemon child (read from child pipe)"); } if (bytes == 0) { warnx("daemon child preparation failed, waiting for child"); status = wait_for_process(child); if (SE_IS_ERROR(status) || SE_PROCSTATUS(status) != 0) errx(SE_PROCSTATUS(status), "daemon child preparation failed (child exited)"); } _exit(0); /* NOTREACHED */ return -1; } #ifdef WIN32 #ifdef dup2 #undef dup2 #endif #define dup2 _dup2 #endif ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL roken_detach_finish(const char *dir, int daemon_child_fd) { char buf[1] = ""; ssize_t bytes; int fd; rk_pidfile(NULL); if (pipefds[1] == -1 && daemon_child_fd != -1) pipefds[1] = daemon_child_fd; if (pipefds[0] != -1) (void) close(pipefds[0]); if (pipefds[1] == -1) return; #ifdef HAVE_SETSID if (setsid() == -1) err(1, "failed to detach from tty"); #endif #ifndef WIN32 /* * Hopefully we've written any pidfiles by now, if they had to be in * the current directory... * * The daemons do re-open logs and so on, therefore this chdir() * call needs to be optional for testing. */ if (dir != NULL && chdir(dir) == -1) err(1, "failed to chdir to /"); #endif do { bytes = write(pipefds[1], buf, sizeof(buf)); } while (bytes == -1 && errno == EINTR); if (bytes == -1) err(1, "failed to signal parent while detaching"); (void) close(pipefds[1]); if (bytes != sizeof(buf)) errx(1, "failed to signal parent while detaching"); fd = open(_PATH_DEVNULL, O_RDWR, 0); if (fd == -1) err(1, "failed to open /dev/null"); /* * Maybe we should check that our output got written, if redirected * to a file. File utils normally do this. */ (void) dup2(fd, STDOUT_FILENO); (void) dup2(fd, STDERR_FILENO); if (fd > 2) (void) close(fd); }