src/shared/spawn-ask-password-agent.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2011 Lennart Poettering
   6 ***/
   7
   8 #include <signal.h>
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11
  12 #include "log.h"
  13 #include "process-util.h"
  14 #include "spawn-ask-password-agent.h"
  15 #include "util.h"
  16
  17 static pid_t agent_pid = 0;
  18
  19 int ask_password_agent_open(void) {
  20         int r;
  21
  22         if (agent_pid > 0)
  23                 return 0;
  24
  25         /* We check STDIN here, not STDOUT, since this is about input,
  26          * not output */
  27         if (!isatty(STDIN_FILENO))
  28                 return 0;
  29
  30         if (!is_main_thread())
  31                 return -EPERM;
  32
  33         r = fork_agent("(sd-askpwagent)",
  34                        NULL, 0,
  35                        &agent_pid,
  36                        SYSTEMD_TTY_ASK_PASSWORD_AGENT_BINARY_PATH,
  37                        SYSTEMD_TTY_ASK_PASSWORD_AGENT_BINARY_PATH, "--watch", NULL);
  38         if (r < 0)
  39                 return log_error_errno(r, "Failed to fork TTY ask password agent: %m");
  40
  41         return 1;
  42 }
  43
  44 void ask_password_agent_close(void) {
  45
  46         if (agent_pid <= 0)
  47                 return;
  48
  49         /* Inform agent that we are done */
  50         (void) kill_and_sigcont(agent_pid, SIGTERM);
  51         (void) wait_for_terminate(agent_pid, NULL);
  52         agent_pid = 0;
  53 }