int child_handle_noninteractive(int fd, wshd_t *w, msg_request_t *req) {
int i, j;
int p[4][2];
int p_[4];
int rv;
msg_response_t res;
msg_response_init(&res);
/* Initialize so that the error handler can do its job */
for (i = 0; i < 4; i++) {
p[i][0] = -1;
p[i][1] = -1;
p_[i] = -1;
}
for (i = 0; i < 4; i++) {
rv = pipe(p[i]);
if (rv == -1) {
perror("pipe");
abort();
}
fcntl_mix_cloexec(p[i][0]);
fcntl_mix_cloexec(p[i][1]);
}
/* Descriptors to send to client */
p_[0] = p[0][1];
p_[1] = p[1][0];
p_[2] = p[2][0];
p_[3] = p[3][0];
rv = un_send_fds(fd, (char *)&res, sizeof(res), p_, 4);
if (rv == -1) {
goto err;
}
rv = child_fork(req, p[0][0], p[1][1], p[2][1]);
assert(rv > 0);
child_pid_to_fd_add(w, rv, p[3][1]);
err:
for (i = 0; i < 4; i++) {
for (j = 0; j < 2; j++) {
if (p[i][j] > -1) {
close(p[i][j]);
p[i][j] = -1;
}
}
}
if (fd > -1) {
close(fd);
fd = -1;
}
return 0;
}
int un_listen(const char *path) {
int fd;
struct sockaddr_un sa;
fd = un__socket();
sa.sun_family = AF_UNIX;
assert(strlen(path) < sizeof(sa.sun_path));
strcpy(sa.sun_path, path);
unlink(sa.sun_path);
fcntl_mix_cloexec(fd);
if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) {
perror("bind");
exit(1);
}
if (listen(fd, 5) == -1) {
perror("listen");
exit(1);
}
return fd;
}
int child_continue(int argc, char **argv) {
wshd_t *w;
int rv;
w = child_load_from_shm();
/* Process MUST not leak file descriptors to children */
barrier_mix_cloexec(&w->barrier_child);
fcntl_mix_cloexec(w->fd);
if (strlen(w->title) > 0) {
setproctitle(argv, w->title);
}
rv = mount_umount_pivoted_root("/mnt");
if (rv == -1) {
exit(1);
}
/* Detach this process from its original group */
rv = setsid();
assert(rv > 0 && rv == getpid());
/* Signal parent */
rv = barrier_signal(&w->barrier_child);
assert(rv == 0);
return child_loop(w);
}
int barrier_open(barrier_t *bar) {
int rv;
int aux[2] = { -1, -1 };
rv = pipe(aux);
if (rv == -1) {
perror("pipe");
goto err;
}
fcntl_mix_cloexec(aux[0]);
fcntl_mix_cloexec(aux[1]);
bar->fd[0] = aux[0];
bar->fd[1] = aux[1];
return 0;
err:
if (aux[0] >= 0) close(aux[0]);
if (aux[1] >= 0) close(aux[1]);
return -1;
}
int child_accept(wshd_t *w) {
int rv, fd;
char buf[MSG_MAX_SIZE];
size_t buflen = sizeof(buf);
msg_request_t req;
rv = accept(w->fd, NULL, NULL);
if (rv == -1) {
perror("accept");
abort();
}
fd = rv;
fcntl_mix_cloexec(fd);
rv = un_recv_fds(fd, buf, buflen, NULL, 0);
if (rv < 0) {
perror("recvmsg");
exit(255);
}
if (rv == 0) {
close(fd);
return 0;
}
assert(rv == sizeof(req));
memcpy(&req, buf, sizeof(req));
if (req.tty) {
return child_handle_interactive(fd, w, &req);
} else {
return child_handle_noninteractive(fd, w, &req);
}
}
