/mandos/release : contents of plugins.d/usplash.c at revision 237.2.8

: (revision 237.2.8)

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/*  -*- coding: utf-8 -*- */
/*
 * Passprompt - Read a password from usplash and output it
 * 
 * Copyright © 2008 Teddy Hogeborn
 * Copyright © 2008 Björn Påhlsson
 * 
 * This program is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see
 * <http://www.gnu.org/licenses/>.
 * 
 * Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
 * <https://www.fukt.bsnet.se/~teddy/>.
 */

#define _GNU_SOURCE		/* asprintf() */
#include <signal.h>		/* sig_atomic_t, struct sigaction,
				   sigemptyset(), sigaddset(), SIGINT,
				   SIGHUP, SIGTERM, sigaction(),
				   SIG_IGN, kill(), SIGKILL */
#include <stdbool.h>		/* bool, false, true */
#include <fcntl.h>		/* open(), O_WRONLY, O_RDONLY */
#include <iso646.h>		/* and, or, not*/
#include <errno.h>		/* errno, EINTR */
#include <sys/types.h>		/* size_t, ssize_t, pid_t, DIR, struct
				   dirent */
#include <stddef.h>		/* NULL */
#include <string.h>		/* strlen(), memcmp() */
#include <stdio.h>		/* asprintf(), perror() */
#include <unistd.h>		/* close(), write(), readlink(),
				   read(), STDOUT_FILENO, sleep(),
				   fork(), setuid(), geteuid(),
				   setsid(), chdir(), dup2(),
				   STDERR_FILENO, execv() */
#include <stdlib.h>		/* free(), EXIT_FAILURE, strtoul(),
				   realloc(), EXIT_SUCCESS, malloc(),
				   _exit() */
#include <stdlib.h>		/* getenv() */
#include <dirent.h>		/* opendir(), readdir(), closedir() */
#include <sys/stat.h>		/* struct stat, lstat(), S_ISLNK */

sig_atomic_t interrupted_by_signal = 0;

static void termination_handler(__attribute__((unused))int signum){
  interrupted_by_signal = 1;
}

static bool usplash_write(const char *cmd, const char *arg){
  /* 
   * usplash_write("TIMEOUT", "15") will write "TIMEOUT 15\0"
   * usplash_write("PULSATE", NULL) will write "PULSATE\0"
   * SEE ALSO
   *         usplash_write(8)
   */
  int ret;
  int fifo_fd;
  do{
    fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
    if(fifo_fd == -1 and (errno != EINTR or interrupted_by_signal)){
      return false;
    }
  }while(fifo_fd == -1);
  
  const char *cmd_line;
  size_t cmd_line_len;
  char *cmd_line_alloc = NULL;
  if(arg == NULL){
    cmd_line = cmd;
    cmd_line_len = strlen(cmd);
  }else{
    do{
      ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
      if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
	int e = errno;
	close(fifo_fd);
	errno = e;
	return false;
      }
    }while(ret == -1);
    cmd_line = cmd_line_alloc;
    cmd_line_len = (size_t)ret + 1;
  }
  
  size_t written = 0;
  while(not interrupted_by_signal and written < cmd_line_len){
    ret = write(fifo_fd, cmd_line + written,
		cmd_line_len - written);
    if(ret == -1){
      if(errno != EINTR or interrupted_by_signal){
	int e = errno;
	close(fifo_fd);
	free(cmd_line_alloc);
	errno = e;
	return false;
      } else {
	continue;
      }
    }
    written += (size_t)ret;
  }
  free(cmd_line_alloc);
  do{
    ret = close(fifo_fd);
    if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
      return false;
    }
  }while(ret == -1);
  if(interrupted_by_signal){
    return false;
  }
  return true;
}

int main(__attribute__((unused))int argc,
	 __attribute__((unused))char **argv){
  int ret = 0;
  ssize_t sret;
  bool an_error_occured = false;
  
  /* Create prompt string */
  char *prompt = NULL;
  {
    const char *const cryptsource = getenv("cryptsource");
    const char *const crypttarget = getenv("crypttarget");
    const char prompt_start[] = "Enter passphrase to unlock the disk";
    
    if(cryptsource == NULL){
      if(crypttarget == NULL){
	ret = asprintf(&prompt, "%s: ", prompt_start);
      } else {
	ret = asprintf(&prompt, "%s (%s): ", prompt_start,
		       crypttarget);
      }
    } else {
      if(crypttarget == NULL){
	ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
      } else {
	ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
		       cryptsource, crypttarget);
      }
    }
    if(ret == -1){
      return EXIT_FAILURE;
    }
  }
  
  /* Find usplash process */
  pid_t usplash_pid = 0;
  char *cmdline = NULL;
  size_t cmdline_len = 0;
  const char usplash_name[] = "/sbin/usplash";
  {
    DIR *proc_dir = opendir("/proc");
    if(proc_dir == NULL){
      free(prompt);
      perror("opendir");
      return EXIT_FAILURE;
    }
    for(struct dirent *proc_ent = readdir(proc_dir);
	proc_ent != NULL;
	proc_ent = readdir(proc_dir)){
      pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
      if(pid == 0){
	/* Not a process */
	continue;
      }
      /* Find the executable name by doing readlink() on the
	 /proc/<pid>/exe link */
      char exe_target[sizeof(usplash_name)];
      {
	/* create file name string */
	char *exe_link;
	ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
	if(ret == -1){
	  perror("asprintf");
	  free(prompt);
	  closedir(proc_dir);
	  return EXIT_FAILURE;
	}
	
	/* Check that it refers to a symlink owned by root:root */
	struct stat exe_stat;
	ret = lstat(exe_link, &exe_stat);
	if(ret == -1){
	  perror("lstat");
	  free(exe_link);
	  free(prompt);
	  closedir(proc_dir);
	  return EXIT_FAILURE;
	}
	if(not S_ISLNK(exe_stat.st_mode)
	   or exe_stat.st_uid != 0
	   or exe_stat.st_gid != 0){
	  free(exe_link);
	  continue;
	}
	
	sret = readlink(exe_link, exe_target, sizeof(exe_target));
	free(exe_link);
	if(sret == -1){
	  continue;
	}
      }
      if((sret == ((ssize_t)sizeof(exe_target)-1))
	 and (memcmp(usplash_name, exe_target,
		     sizeof(exe_target)-1) == 0)){
	usplash_pid = pid;
	/* Read and save the command line of usplash in "cmdline" */
	{
	  /* Open /proc/<pid>/cmdline  */
	  int cl_fd;
	  {
	    char *cmdline_filename;
	    ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
			   proc_ent->d_name);
	    if(ret == -1){
	      perror("asprintf");
	      free(prompt);
	      closedir(proc_dir);
	      return EXIT_FAILURE;
	    }
	    cl_fd = open(cmdline_filename, O_RDONLY);
	    if(cl_fd == -1){
	      perror("open");
	      free(cmdline_filename);
	      free(prompt);
	      closedir(proc_dir);
	      return EXIT_FAILURE;
	    }
	    free(cmdline_filename);
	  }
	  size_t cmdline_allocated = 0;
	  char *tmp;
	  const size_t blocksize = 1024;
	  do{
	    if(cmdline_len + blocksize > cmdline_allocated){
	      tmp = realloc(cmdline, cmdline_allocated + blocksize);
	      if(tmp == NULL){
		perror("realloc");
		free(cmdline);
		free(prompt);
		closedir(proc_dir);
		return EXIT_FAILURE;
	      }
	      cmdline = tmp;
	      cmdline_allocated += blocksize;
	    }
	    sret = read(cl_fd, cmdline + cmdline_len,
			cmdline_allocated - cmdline_len);
	    if(sret == -1){
	      perror("read");
	      free(cmdline);
	      free(prompt);
	      closedir(proc_dir);
	      return EXIT_FAILURE;
	    }
	    cmdline_len += (size_t)sret;
	  } while(sret != 0);
	  close(cl_fd);
	}
	break;
      }
    }
    closedir(proc_dir);
  }
  if(usplash_pid == 0){
    free(prompt);
    return EXIT_FAILURE;
  }
  
  /* Set up the signal handler */
  {
    struct sigaction old_action,
      new_action = { .sa_handler = termination_handler,
		     .sa_flags = 0 };
    sigemptyset(&new_action.sa_mask);
    sigaddset(&new_action.sa_mask, SIGINT);
    sigaddset(&new_action.sa_mask, SIGHUP);
    sigaddset(&new_action.sa_mask, SIGTERM);
    ret = sigaction(SIGINT, NULL, &old_action);
    if(ret == -1){
      perror("sigaction");
      free(prompt);
      return EXIT_FAILURE;
    }
    if(old_action.sa_handler != SIG_IGN){
      ret = sigaction(SIGINT, &new_action, NULL);
      if(ret == -1){
	perror("sigaction");
	free(prompt);
	return EXIT_FAILURE;
      }
    }
    ret = sigaction(SIGHUP, NULL, &old_action);
    if(ret == -1){
      perror("sigaction");
      free(prompt);
      return EXIT_FAILURE;
    }
    if(old_action.sa_handler != SIG_IGN){
      ret = sigaction(SIGHUP, &new_action, NULL);
      if(ret == -1){
	perror("sigaction");
	free(prompt);
	return EXIT_FAILURE;
      }
    }
    ret = sigaction(SIGTERM, NULL, &old_action);
    if(ret == -1){
      perror("sigaction");
      free(prompt);
      return EXIT_FAILURE;
    }
    if(old_action.sa_handler != SIG_IGN){
      ret = sigaction(SIGTERM, &new_action, NULL);
      if(ret == -1){
	perror("sigaction");
	free(prompt);
	return EXIT_FAILURE;
      }
    }
  }
  
  /* Write command to FIFO */
  if(not interrupted_by_signal){
    if(not usplash_write("TIMEOUT", "0")
       and (errno != EINTR)){
      perror("usplash_write");
      an_error_occured = true;
    }
  }
  if(not interrupted_by_signal and not an_error_occured){
    if(not usplash_write("INPUTQUIET", prompt)
       and (errno != EINTR)){
      perror("usplash_write");
      an_error_occured = true;
    }
  }
  free(prompt);
  
  /* This is not really a loop; while() is used to be able to "break"
     out of it; those breaks are marked "Big" */
  while(not interrupted_by_signal and not an_error_occured){
    char *buf = NULL;
    size_t buf_len = 0;
    
    /* Open FIFO */
    int fifo_fd;
    do{
      fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
      if(fifo_fd == -1){
	if(errno != EINTR){
	  perror("open");
	  an_error_occured = true;
	  break;
	}
	if(interrupted_by_signal){
	  break;
	}
      }
    }while(fifo_fd == -1);
    if(interrupted_by_signal or an_error_occured){
      break;			/* Big */
    }
    
    /* Read from FIFO */
    size_t buf_allocated = 0;
    const size_t blocksize = 1024;
    do{
      if(buf_len + blocksize > buf_allocated){
	char *tmp = realloc(buf, buf_allocated + blocksize);
	if(tmp == NULL){
	  perror("realloc");
	  an_error_occured = true;
	  break;
	}
	buf = tmp;
	buf_allocated += blocksize;
      }
      do{
	sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
	if(sret == -1){
	  if(errno != EINTR){
	    perror("read");
	    an_error_occured = true;
	    break;
	  }
	  if(interrupted_by_signal){
	    break;
	  }
	}
      }while(sret == -1);
      if(interrupted_by_signal or an_error_occured){
	break;
      }
      
      buf_len += (size_t)sret;
    }while(sret != 0);
    close(fifo_fd);
    if(interrupted_by_signal or an_error_occured){
      break;			/* Big */
    }
    
    if(not usplash_write("TIMEOUT", "15")
       and (errno != EINTR)){
	perror("usplash_write");
	an_error_occured = true;
    }
    if(interrupted_by_signal or an_error_occured){
      break;			/* Big */
    }
    
    /* Print password to stdout */
    size_t written = 0;
    while(written < buf_len){
      do{
	sret = write(STDOUT_FILENO, buf + written, buf_len - written);
	if(sret == -1){
	  if(errno != EINTR){
	    perror("write");
	    an_error_occured = true;
	    break;
	  }
	  if(interrupted_by_signal){
	    break;
	  }
	}
      }while(sret == -1);
      if(interrupted_by_signal or an_error_occured){
	break;
      }
      written += (size_t)sret;
    }
    free(buf);
    if(not interrupted_by_signal and not an_error_occured){
      free(cmdline);
      return EXIT_SUCCESS;
    }
    break;			/* Big */
  }				/* end of non-loop while() */
  
  /* If we got here, an error or interrupt must have happened */
  
  /* Create argc and argv for new usplash*/
  int cmdline_argc = 0;
  char **cmdline_argv = malloc(sizeof(char *));
  {
    size_t position = 0;
    while(position < cmdline_len){
      char **tmp = realloc(cmdline_argv,
			   (sizeof(char *)
			    * (size_t)(cmdline_argc + 2)));
      if(tmp == NULL){
	perror("realloc");
	free(cmdline_argv);
	return EXIT_FAILURE;
      }
      cmdline_argv = tmp;
      cmdline_argv[cmdline_argc] = cmdline + position;
      cmdline_argc++;
      position += strlen(cmdline + position) + 1;
    }
    cmdline_argv[cmdline_argc] = NULL;
  }
  /* Kill old usplash */
  kill(usplash_pid, SIGTERM);
  sleep(2);
  while(kill(usplash_pid, 0) == 0){
    kill(usplash_pid, SIGKILL);
    sleep(1);
  }
  pid_t new_usplash_pid = fork();
  if(new_usplash_pid == 0){
    /* Child; will become new usplash process */
    
    /* Make the effective user ID (root) the only user ID instead of
       the real user ID (mandos) */
    ret = setuid(geteuid());
    if(ret == -1){
      perror("setuid");
    }
    
    setsid();
    ret = chdir("/");
/*     if(fork() != 0){ */
/*       _exit(EXIT_SUCCESS); */
/*     } */
    ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
    if(ret == -1){
      perror("dup2");
      _exit(EXIT_FAILURE);
    }
    
    execv(usplash_name, cmdline_argv);
    if(not interrupted_by_signal){
      perror("execv");
    }
    free(cmdline);
    free(cmdline_argv);
    _exit(EXIT_FAILURE);
  }
  free(cmdline);
  free(cmdline_argv);
  sleep(2);
  if(not usplash_write("PULSATE", NULL)
     and (errno != EINTR)){
    perror("usplash_write");
  }
  
  return EXIT_FAILURE;
}

237.1.2 by Teddy Hogeborn Further steps towards a D-Bus server interface, plus minor syntax	1	/* -- coding: utf-8 -- */
	2	/*
	3	* Passprompt - Read a password from usplash and output it
	4	*
	5	* Copyright © 2008 Teddy Hogeborn
	6	* Copyright © 2008 Björn Påhlsson
	7	*
	8	* This program is free software: you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License as
	10	* published by the Free Software Foundation, either version 3 of the
	11	* License, or (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful, but
	14	* WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program. If not, see
	20	* <http://www.gnu.org/licenses/>.
	21	*
	22	* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
	23	* <https://www.fukt.bsnet.se/~teddy/>.
	24	*/
	25
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	26	#define _GNU_SOURCE /* asprintf() */
	27	#include <signal.h> /* sig_atomic_t, struct sigaction,
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	28	sigemptyset(), sigaddset(), SIGINT,
	29	SIGHUP, SIGTERM, sigaction(),
	30	SIG_IGN, kill(), SIGKILL */
	31	#include <stdbool.h> /* bool, false, true */
	32	#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	33	#include <iso646.h> /* and, or, not*/
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	34	#include <errno.h> /* errno, EINTR */
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	35	#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
	36	dirent */
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	37	#include <stddef.h> /* NULL */
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	38	#include <string.h> /* strlen(), memcmp() */
	39	#include <stdio.h> /* asprintf(), perror() */
	40	#include <unistd.h> /* close(), write(), readlink(),
	41	read(), STDOUT_FILENO, sleep(),
	42	fork(), setuid(), geteuid(),
	43	setsid(), chdir(), dup2(),
	44	STDERR_FILENO, execv() */
	45	#include <stdlib.h> /* free(), EXIT_FAILURE, strtoul(),
	46	realloc(), EXIT_SUCCESS, malloc(),
	47	_exit() */
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	48	#include <stdlib.h> /* getenv() */
	49	#include <dirent.h> /* opendir(), readdir(), closedir() */
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	50	#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	51
	52	sig_atomic_t interrupted_by_signal = 0;
	53
	54	static void termination_handler(__attribute__((unused))int signum){
	55	interrupted_by_signal = 1;
	56	}
	57
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	58	static bool usplash_write(const char cmd, const char arg){
	59	/*
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	60	* usplash_write("TIMEOUT", "15") will write "TIMEOUT 15\0"
	61	* usplash_write("PULSATE", NULL) will write "PULSATE\0"
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	62	* SEE ALSO
	63	* usplash_write(8)
	64	*/
	65	int ret;
	66	int fifo_fd;
	67	do{
	68	fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
	69	if(fifo_fd == -1 and (errno != EINTR or interrupted_by_signal)){
	70	return false;
	71	}
	72	}while(fifo_fd == -1);
	73
	74	const char *cmd_line;
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	75	size_t cmd_line_len;
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	76	char *cmd_line_alloc = NULL;
	77	if(arg == NULL){
	78	cmd_line = cmd;
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	79	cmd_line_len = strlen(cmd);
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	80	}else{
	81	do{
	82	ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
	83	if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
	84	int e = errno;
	85	close(fifo_fd);
	86	errno = e;
	87	return false;
	88	}
	89	}while(ret == -1);
	90	cmd_line = cmd_line_alloc;
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	91	cmd_line_len = (size_t)ret + 1;
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	92	}
	93
	94	size_t written = 0;
	95	while(not interrupted_by_signal and written < cmd_line_len){
	96	ret = write(fifo_fd, cmd_line + written,
	97	cmd_line_len - written);
	98	if(ret == -1){
	99	if(errno != EINTR or interrupted_by_signal){
	100	int e = errno;
	101	close(fifo_fd);
	102	free(cmd_line_alloc);
	103	errno = e;
	104	return false;
	105	} else {
	106	continue;
	107	}
	108	}
	109	written += (size_t)ret;
	110	}
	111	free(cmd_line_alloc);
	112	do{
	113	ret = close(fifo_fd);
	114	if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
	115	return false;
	116	}
	117	}while(ret == -1);
	118	if(interrupted_by_signal){
	119	return false;
	120	}
	121	return true;
	122	}
	123
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	124	int main(__attribute__((unused))int argc,
	125	__attribute__((unused))char **argv){
	126	int ret = 0;
	127	ssize_t sret;
	128	bool an_error_occured = false;
	129
	130	/* Create prompt string */
	131	char *prompt = NULL;
	132	{
	133	const char *const cryptsource = getenv("cryptsource");
	134	const char *const crypttarget = getenv("crypttarget");
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	135	const char prompt_start[] = "Enter passphrase to unlock the disk";
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	136
	137	if(cryptsource == NULL){
	138	if(crypttarget == NULL){
	139	ret = asprintf(&prompt, "%s: ", prompt_start);
	140	} else {
	141	ret = asprintf(&prompt, "%s (%s): ", prompt_start,
	142	crypttarget);
	143	}
	144	} else {
	145	if(crypttarget == NULL){
	146	ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
	147	} else {
	148	ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
	149	cryptsource, crypttarget);
	150	}
	151	}
	152	if(ret == -1){
	153	return EXIT_FAILURE;
	154	}
	155	}
	156
	157	/* Find usplash process */
	158	pid_t usplash_pid = 0;
	159	char *cmdline = NULL;
	160	size_t cmdline_len = 0;
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	161	const char usplash_name[] = "/sbin/usplash";
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	162	{
	163	DIR *proc_dir = opendir("/proc");
	164	if(proc_dir == NULL){
	165	free(prompt);
	166	perror("opendir");
	167	return EXIT_FAILURE;
	168	}
	169	for(struct dirent *proc_ent = readdir(proc_dir);
	170	proc_ent != NULL;
	171	proc_ent = readdir(proc_dir)){
	172	pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
	173	if(pid == 0){
	174	/* Not a process */
	175	continue;
	176	}
	177	/* Find the executable name by doing readlink() on the
	178	/proc/<pid>/exe link */
	179	char exe_target[sizeof(usplash_name)];
	180	{
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	181	/* create file name string */
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	182	char *exe_link;
	183	ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
	184	if(ret == -1){
	185	perror("asprintf");
	186	free(prompt);
	187	closedir(proc_dir);
	188	return EXIT_FAILURE;
	189	}
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	190
	191	/* Check that it refers to a symlink owned by root:root */
	192	struct stat exe_stat;
	193	ret = lstat(exe_link, &exe_stat);
	194	if(ret == -1){
	195	perror("lstat");
	196	free(exe_link);
	197	free(prompt);
	198	closedir(proc_dir);
	199	return EXIT_FAILURE;
	200	}
	201	if(not S_ISLNK(exe_stat.st_mode)
	202	or exe_stat.st_uid != 0
	203	or exe_stat.st_gid != 0){
	204	free(exe_link);
	205	continue;
	206	}
	207
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	208	sret = readlink(exe_link, exe_target, sizeof(exe_target));
	209	free(exe_link);
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	210	if(sret == -1){
	211	continue;
	212	}
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	213	}
	214	if((sret == ((ssize_t)sizeof(exe_target)-1))
	215	and (memcmp(usplash_name, exe_target,
	216	sizeof(exe_target)-1) == 0)){
	217	usplash_pid = pid;
	218	/* Read and save the command line of usplash in "cmdline" */
	219	{
	220	/* Open /proc/<pid>/cmdline */
	221	int cl_fd;
	222	{
	223	char *cmdline_filename;
	224	ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
	225	proc_ent->d_name);
	226	if(ret == -1){
	227	perror("asprintf");
	228	free(prompt);
	229	closedir(proc_dir);
	230	return EXIT_FAILURE;
	231	}
	232	cl_fd = open(cmdline_filename, O_RDONLY);
	233	if(cl_fd == -1){
	234	perror("open");
	235	free(cmdline_filename);
	236	free(prompt);
	237	closedir(proc_dir);
	238	return EXIT_FAILURE;
	239	}
	240	free(cmdline_filename);
	241	}
	242	size_t cmdline_allocated = 0;
	243	char *tmp;
	244	const size_t blocksize = 1024;
	245	do{
	246	if(cmdline_len + blocksize > cmdline_allocated){
	247	tmp = realloc(cmdline, cmdline_allocated + blocksize);
	248	if(tmp == NULL){
	249	perror("realloc");
	250	free(cmdline);
	251	free(prompt);
	252	closedir(proc_dir);
	253	return EXIT_FAILURE;
	254	}
	255	cmdline = tmp;
	256	cmdline_allocated += blocksize;
	257	}
	258	sret = read(cl_fd, cmdline + cmdline_len,
	259	cmdline_allocated - cmdline_len);
	260	if(sret == -1){
	261	perror("read");
	262	free(cmdline);
	263	free(prompt);
	264	closedir(proc_dir);
	265	return EXIT_FAILURE;
	266	}
	267	cmdline_len += (size_t)sret;
	268	} while(sret != 0);
	269	close(cl_fd);
	270	}
	271	break;
	272	}
	273	}
	274	closedir(proc_dir);
	275	}
	276	if(usplash_pid == 0){
277	free(prompt);
278	return EXIT_FAILURE;
279	}
280
281	/* Set up the signal handler */
282	{
283	struct sigaction old_action,
284	new_action = { .sa_handler = termination_handler,
285	.sa_flags = 0 };
286	sigemptyset(&new_action.sa_mask);
287	sigaddset(&new_action.sa_mask, SIGINT);
288	sigaddset(&new_action.sa_mask, SIGHUP);
289	sigaddset(&new_action.sa_mask, SIGTERM);
290	ret = sigaction(SIGINT, NULL, &old_action);
291	if(ret == -1){
292	perror("sigaction");
293	free(prompt);
294	return EXIT_FAILURE;
295	}
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	296	if(old_action.sa_handler != SIG_IGN){
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	297	ret = sigaction(SIGINT, &new_action, NULL);
	298	if(ret == -1){
	299	perror("sigaction");
	300	free(prompt);
	301	return EXIT_FAILURE;
	302	}
	303	}
	304	ret = sigaction(SIGHUP, NULL, &old_action);
	305	if(ret == -1){
	306	perror("sigaction");
	307	free(prompt);
	308	return EXIT_FAILURE;
	309	}
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	310	if(old_action.sa_handler != SIG_IGN){
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	311	ret = sigaction(SIGHUP, &new_action, NULL);
	312	if(ret == -1){
	313	perror("sigaction");
	314	free(prompt);
	315	return EXIT_FAILURE;
	316	}
	317	}
	318	ret = sigaction(SIGTERM, NULL, &old_action);
	319	if(ret == -1){
	320	perror("sigaction");
	321	free(prompt);
	322	return EXIT_FAILURE;
	323	}
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	324	if(old_action.sa_handler != SIG_IGN){
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	325	ret = sigaction(SIGTERM, &new_action, NULL);
	326	if(ret == -1){
	327	perror("sigaction");
	328	free(prompt);
	329	return EXIT_FAILURE;
	330	}
	331	}
	332	}
	333
	334	/* Write command to FIFO */
	335	if(not interrupted_by_signal){
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	336	if(not usplash_write("TIMEOUT", "0")
	337	and (errno != EINTR)){
	338	perror("usplash_write");
	339	an_error_occured = true;
	340	}
	341	}
	342	if(not interrupted_by_signal and not an_error_occured){
	343	if(not usplash_write("INPUTQUIET", prompt)
	344	and (errno != EINTR)){
	345	perror("usplash_write");
	346	an_error_occured = true;
	347	}
	348	}
	349	free(prompt);
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	350
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	351	/* This is not really a loop; while() is used to be able to "break"
	352	out of it; those breaks are marked "Big" */
	353	while(not interrupted_by_signal and not an_error_occured){
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	354	char *buf = NULL;
	355	size_t buf_len = 0;
	356
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	357	/* Open FIFO */
	358	int fifo_fd;
	359	do{
	360	fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
	361	if(fifo_fd == -1){
	362	if(errno != EINTR){
	363	perror("open");
	364	an_error_occured = true;
	365	break;
	366	}
	367	if(interrupted_by_signal){
	368	break;
	369	}
	370	}
	371	}while(fifo_fd == -1);
	372	if(interrupted_by_signal or an_error_occured){
	373	break; /* Big */
	374	}
	375
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	376	/* Read from FIFO */
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	377	size_t buf_allocated = 0;
	378	const size_t blocksize = 1024;
	379	do{
	380	if(buf_len + blocksize > buf_allocated){
	381	char *tmp = realloc(buf, buf_allocated + blocksize);
	382	if(tmp == NULL){
	383	perror("realloc");
	384	an_error_occured = true;
	385	break;
	386	}
	387	buf = tmp;
	388	buf_allocated += blocksize;
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	389	}
	390	do{
	391	sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
	392	if(sret == -1){
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	393	if(errno != EINTR){
	394	perror("read");
	395	an_error_occured = true;
	396	break;
	397	}
	398	if(interrupted_by_signal){
	399	break;
	400	}
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	401	}
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	402	}while(sret == -1);
	403	if(interrupted_by_signal or an_error_occured){
	404	break;
	405	}
	406
	407	buf_len += (size_t)sret;
	408	}while(sret != 0);
	409	close(fifo_fd);
	410	if(interrupted_by_signal or an_error_occured){
	411	break; /* Big */
	412	}
	413
	414	if(not usplash_write("TIMEOUT", "15")
	415	and (errno != EINTR)){
	416	perror("usplash_write");
	417	an_error_occured = true;
	418	}
	419	if(interrupted_by_signal or an_error_occured){
	420	break; /* Big */
	421	}
	422
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	423	/* Print password to stdout */
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	424	size_t written = 0;
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	425	while(written < buf_len){
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	426	do{
	427	sret = write(STDOUT_FILENO, buf + written, buf_len - written);
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	428	if(sret == -1){
	429	if(errno != EINTR){
	430	perror("write");
	431	an_error_occured = true;
	432	break;
	433	}
	434	if(interrupted_by_signal){
	435	break;
	436	}
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	437	}
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	438	}while(sret == -1);
	439	if(interrupted_by_signal or an_error_occured){
	440	break;
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	441	}
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	442	written += (size_t)sret;
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	443	}
	444	free(buf);
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	445	if(not interrupted_by_signal and not an_error_occured){
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	446	free(cmdline);
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	447	return EXIT_SUCCESS;
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	448	}
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	449	break; /* Big */
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	450	} /* end of non-loop while() */
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	451
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	452	/* If we got here, an error or interrupt must have happened */
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	453
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	454	/* Create argc and argv for new usplash*/
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	455	int cmdline_argc = 0;
	456	char *cmdline_argv = malloc(sizeof(char ));
	457	{
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	458	size_t position = 0;
	459	while(position < cmdline_len){
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	460	char **tmp = realloc(cmdline_argv,
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	461	(sizeof(char *)
	462	* (size_t)(cmdline_argc + 2)));
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	463	if(tmp == NULL){
	464	perror("realloc");
	465	free(cmdline_argv);
	466	return EXIT_FAILURE;
	467	}
	468	cmdline_argv = tmp;
	469	cmdline_argv[cmdline_argc] = cmdline + position;
	470	cmdline_argc++;
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	471	position += strlen(cmdline + position) + 1;
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	472	}
	473	cmdline_argv[cmdline_argc] = NULL;
	474	}
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	475	/* Kill old usplash */
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	476	kill(usplash_pid, SIGTERM);
	477	sleep(2);
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	478	while(kill(usplash_pid, 0) == 0){
	479	kill(usplash_pid, SIGKILL);
	480	sleep(1);
	481	}
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	482	pid_t new_usplash_pid = fork();
	483	if(new_usplash_pid == 0){
	484	/* Child; will become new usplash process */
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	485
	486	/* Make the effective user ID (root) the only user ID instead of
	487	the real user ID (mandos) */
	488	ret = setuid(geteuid());
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	489	if(ret == -1){
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	490	perror("setuid");
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	491	}
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	492
	493	setsid();
	494	ret = chdir("/");
	495	/* if(fork() != 0){ */
	496	/* _exit(EXIT_SUCCESS); */
	497	/* } */
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	498	ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
	499	if(ret == -1){
	500	perror("dup2");
	501	_exit(EXIT_FAILURE);
	502	}
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	503
	504	execv(usplash_name, cmdline_argv);
223 by Teddy Hogeborn * .bzrignore (plugins.d/askpass-fifo): Added.	505	if(not interrupted_by_signal){
	506	perror("execv");
	507	}
213 by Teddy Hogeborn * plugins.d/usplash.c (main): Bug fix: Do not free "cmdline" too soon.	508	free(cmdline);
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	509	free(cmdline_argv);
	510	_exit(EXIT_FAILURE);
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	511	}
213 by Teddy Hogeborn * plugins.d/usplash.c (main): Bug fix: Do not free "cmdline" too soon.	512	free(cmdline);
212 by Teddy Hogeborn * plugins.d/usplash.c (usplash_write): Move "cmd_line_len" up.	513	free(cmdline_argv);
210 by Teddy Hogeborn * debian/mandos-client.postinst: Change home directory to	514	sleep(2);
	515	if(not usplash_write("PULSATE", NULL)
	516	and (errno != EINTR)){
	517	perror("usplash_write");
208 by Teddy Hogeborn * Makefile (PLUGINS): Added "plugins.d/usplash".	518	}
	519
	520	return EXIT_FAILURE;
	521	}