/mandos/release

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bzr branch http://bzr.recompile.se/loggerhead/mandos/release
24.1.157 by Björn Påhlsson
added the actually plugin file for plymouth
1
#define _GNU_SOURCE		/* asprintf(), TEMP_FAILURE_RETRY() */
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#include <signal.h>		/* sig_atomic_t, struct sigaction,
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				   sigemptyset(), sigaddset(), SIGINT,
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				   SIGHUP, SIGTERM, sigaction(),
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				   kill(), SIG_IGN */
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#include <stdbool.h>		/* bool, false, true */
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#include <fcntl.h>		/* open(), O_RDONLY */
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#include <iso646.h>		/* and, or, not*/
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#include <sys/types.h>		/* size_t, ssize_t, pid_t, struct dirent,
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				   waitpid() */
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#include <sys/wait.h>		/* waitpid() */
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#include <stddef.h>		/* NULL */
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#include <string.h>		/* strchr(), memcmp() */
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#include <stdio.h>		/* asprintf(), perror(), fopen(), fscanf() */
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#include <unistd.h>		/* close(), readlink(), read(), fork()
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				   setsid(), chdir(), dup2()
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				   STDERR_FILENO, execv(), access() */
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#include <stdlib.h>		/* free(), EXIT_FAILURE, realloc(),
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				   EXIT_SUCCESS, malloc(), _exit(),
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				   getenv() */
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#include <dirent.h>		/* scandir(), alphasort() */
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#include <inttypes.h>		/* intmax_t, strtoumax(), SCNuMAX */
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#include <sys/stat.h>		/* struct stat, lstat() */
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#include <sysexits.h>		/* EX_OSERR */
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#include <error.h>		/* error() */
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#include <errno.h>		/* TEMP_FAILURE_RETRY */
237.2.194 by teddy at bsnet
* debian/watch: Also watch for "*.tar.xz" files.
27
#include <argz.h>		/* argz_count(), argz_extract() */
24.1.157 by Björn Påhlsson
added the actually plugin file for plymouth
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29
sig_atomic_t interrupted_by_signal = 0;
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const char plymouth_pid[] = "/dev/.initramfs/plymouth.pid";
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const char plymouth_path[] = "/bin/plymouth";
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const char plymouthd_path[] = "/sbin/plymouthd";
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const char *plymouthd_default_argv[] = {"/sbin/plymouthd", "--mode=boot",
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					"--attach-to-session",
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					"--pid-file=/dev/.initramfs/plymouth.pid",
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					NULL };
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static void termination_handler(__attribute__((unused))int signum){
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  if(interrupted_by_signal){
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    return;
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  }
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  interrupted_by_signal = 1;
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}
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/* Create prompt string */
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char *makeprompt(void){
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  int ret = 0;
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  char *prompt;
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  const char *const cryptsource = getenv("cryptsource");
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  const char *const crypttarget = getenv("crypttarget");
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  const char prompt_start[] = "Enter passphrase to unlock the disk";
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  if(cryptsource == NULL){
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    if(crypttarget == NULL){
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      ret = asprintf(&prompt, "%s: ", prompt_start);
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    } else {
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      ret = asprintf(&prompt, "%s (%s): ", prompt_start,
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		     crypttarget);
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    }
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  } else {
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    if(crypttarget == NULL){
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      ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
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    } else {
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      ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
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		     cryptsource, crypttarget);
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    }
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  }
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  if(ret == -1){
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    return NULL;
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  }
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  return prompt;
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}
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void kill_and_wait(pid_t pid){
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  TEMP_FAILURE_RETRY(kill(pid, SIGTERM));
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  TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
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}
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bool become_a_daemon(void){
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  int ret = setuid(geteuid());
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  if(ret == -1){
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    error(0, errno, "setuid");
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  }
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  setsid();
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  ret = chdir("/");
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  if(ret == -1){
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    error(0, errno, "chdir");
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    return false;
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  }
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  ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
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  if(ret == -1){
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    error(0, errno, "dup2");
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    return false;
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  }
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  return true;
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}
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bool exec_and_wait(pid_t *pid_return, const char *path,
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		   const char **argv, bool interruptable,
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		   bool daemonize){
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  int status;
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  int ret;
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  pid_t pid;
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  pid = fork();
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  if(pid == -1){
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    error(0, errno, "fork");
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    return false;
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  }
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  if(pid == 0){
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    /* Child */
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    if(daemonize){
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      if(not become_a_daemon()){
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	_exit(EX_OSERR);
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      }
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    }
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    char **new_argv = NULL;
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    char *tmp;
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    int i = 0;
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    for (; argv[i]!=(char *)NULL; i++){
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      tmp = realloc(new_argv, sizeof(const char *) * ((size_t)i + 1));
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      if (tmp == NULL){
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	error(0, errno, "realloc");
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	free(new_argv);
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	_exit(EXIT_FAILURE);
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      }
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      new_argv = (char **)tmp;
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      new_argv[i] = strdup(argv[i]);
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    }
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    new_argv[i] = (char *) NULL;
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    execv(path, (char *const *)new_argv);
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    error(0, errno, "execv");
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    _exit(EXIT_FAILURE);
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  }
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  if(pid_return != NULL){
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    *pid_return = pid;
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  }
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  do {
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    ret = waitpid(pid, &status, 0);
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  } while(ret == -1 and errno == EINTR
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	  and ((not interrupted_by_signal)
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	       or (not interruptable)));
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  if(interrupted_by_signal and interruptable){
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    return false;
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  }
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  if(ret == -1){
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    error(0, errno, "waitpid");
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    return false;
151
  }
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  if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
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    return true;
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  }
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  return false;
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}
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int is_plymouth(const struct dirent *proc_entry){
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  int ret;
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  {
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    uintmax_t maxvalue;
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    char *tmp;
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    errno = 0;
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    maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
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    if(errno != 0 or *tmp != '\0' or maxvalue != (uintmax_t)((pid_t)maxvalue)){
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      return 0;
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    }
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  }
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  char exe_target[sizeof(plymouth_path)];
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  char *exe_link;
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  ret = asprintf(&exe_link, "/proc/%s/exe", proc_entry->d_name);
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  if(ret == -1){
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    error(0, errno, "asprintf");
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    return 0;
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  }
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  struct stat exe_stat;
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  ret = lstat(exe_link, &exe_stat);
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  if(ret == -1){
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    free(exe_link);
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    if(errno != ENOENT){
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      error(0, errno, "lstat");
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    }
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    return 0;
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  }
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  if(not S_ISLNK(exe_stat.st_mode)
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     or exe_stat.st_uid != 0
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     or exe_stat.st_gid != 0){
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    free(exe_link);
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    return 0;
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  }
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  ssize_t sret = readlink(exe_link, exe_target, sizeof(exe_target));
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  free(exe_link);
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  if((sret != (ssize_t)sizeof(plymouth_path)-1) or
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      (memcmp(plymouth_path, exe_target,
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	      sizeof(plymouth_path)-1) != 0)){
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    return 0;
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  }
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  return 1;
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}
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pid_t get_pid(void){
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  int ret;
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  FILE *pidfile = fopen(plymouth_pid, "r");
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  uintmax_t maxvalue = 0;
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  if(pidfile != NULL){
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    ret = fscanf(pidfile, "%" SCNuMAX, &maxvalue);
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    if(ret != 1){
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      maxvalue = 0;
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    }
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    fclose(pidfile);
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  }
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  if(maxvalue == 0){
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    struct dirent **direntries;
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    ret = scandir("/proc", &direntries, is_plymouth, alphasort);
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    sscanf(direntries[0]->d_name, "%" SCNuMAX, &maxvalue);
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  }
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  pid_t pid;
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  pid = (pid_t)maxvalue;
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  if((uintmax_t)pid == maxvalue){
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    return pid;
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  }
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  return 0;
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}
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const char **getargv(pid_t pid){
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  int cl_fd;
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  char *cmdline_filename;
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  ssize_t sret;
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  int ret;
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  ret = asprintf(&cmdline_filename, "/proc/%" PRIuMAX "/cmdline",
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		 (uintmax_t)pid);
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  if(ret == -1){
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    error(0, errno, "asprintf");
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    return NULL;
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  }
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  /* Open /proc/<pid>/cmdline  */
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  cl_fd = open(cmdline_filename, O_RDONLY);
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  free(cmdline_filename);
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  if(cl_fd == -1){
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    error(0, errno, "open");
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    return NULL;
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  }
250
  
251
  size_t cmdline_allocated = 0;
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  size_t cmdline_len = 0;
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  char *cmdline = NULL;
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  char *tmp;
255
  const size_t blocksize = 1024;
256
  do {
257
    /* Allocate more space? */
258
    if(cmdline_len + blocksize > cmdline_allocated){
259
      tmp = realloc(cmdline, cmdline_allocated + blocksize);
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      if(tmp == NULL){
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	error(0, errno, "realloc");
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	free(cmdline);
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	close(cl_fd);
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	return NULL;
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      }
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      cmdline = tmp;
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      cmdline_allocated += blocksize;
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    }
269
    
270
    /* Read data */
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    sret = read(cl_fd, cmdline + cmdline_len,
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		cmdline_allocated - cmdline_len);
273
    if(sret == -1){
274
      error(0, errno, "read");
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      free(cmdline);
276
      close(cl_fd);
277
      return NULL;
278
    }
279
    cmdline_len += (size_t)sret;
280
  } while(sret != 0);
281
  ret = close(cl_fd);
282
  if(ret == -1){
283
    error(0, errno, "close");
284
    free(cmdline);
285
    return NULL;
286
  }
287
  
288
  /* we got cmdline and cmdline_len, ignore rest... */
237.2.194 by teddy at bsnet
* debian/watch: Also watch for "*.tar.xz" files.
289
  char **argv = malloc((argz_count(cmdline, cmdline_len)+1)
290
		       * sizeof(char *)); /* Get number of args */
291
  if(argv == NULL){
292
    error(0, errno, "argv = malloc()");
293
    free(cmdline);
294
    return NULL;
24.1.157 by Björn Påhlsson
added the actually plugin file for plymouth
295
  }
237.2.194 by teddy at bsnet
* debian/watch: Also watch for "*.tar.xz" files.
296
  argz_extract(cmdline, cmdline_len, argv); /* Create argv */
297
  return (const char **)argv;
24.1.157 by Björn Påhlsson
added the actually plugin file for plymouth
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}
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300
int main(__attribute__((unused))int argc,
301
	 __attribute__((unused))char **argv){
302
  char *prompt;
303
  char *prompt_arg;
304
  pid_t plymouth_command_pid;
305
  int ret;
306
  bool bret;
307
308
  /* test -x /bin/plymouth */
309
  ret = access(plymouth_path, X_OK);
310
  if(ret == -1){
311
    exit(EXIT_FAILURE);
312
  }
313
314
  { /* Add signal handlers */
315
    struct sigaction old_action,
316
      new_action = { .sa_handler = termination_handler,
317
		     .sa_flags = 0 };
318
    sigemptyset(&new_action.sa_mask);
319
    for(int *sig = (int[]){ SIGINT, SIGHUP, SIGTERM, 0 }; *sig != 0; sig++){
320
      ret = sigaddset(&new_action.sa_mask, *sig);
321
      if(ret == -1){
322
	error(0, errno, "sigaddset");
323
	exit(EX_OSERR);
324
      }
325
      ret = sigaction(*sig, NULL, &old_action);
326
      if(ret == -1){
327
	error(0, errno, "sigaction");
328
	exit(EX_OSERR);
329
      }
330
      if(old_action.sa_handler != SIG_IGN){
331
	ret = sigaction(*sig, &new_action, NULL);
332
	if(ret == -1){
333
	  error(0, errno, "sigaction");
334
	  exit(EX_OSERR);
335
	}
336
      }
337
    }
338
  }
339
    
340
  /* plymouth --ping */
341
  bret = exec_and_wait(&plymouth_command_pid, plymouth_path,
342
		       (const char *[]){ (const char *)plymouth_path, (const char *)"--ping", (const char *)NULL},
343
		       true, false);
344
  if(not bret){
345
    if(interrupted_by_signal){
346
      kill_and_wait(plymouth_command_pid);
347
    }
348
    exit(EXIT_FAILURE);
349
  }
350
  
351
  prompt = makeprompt();
352
  ret = asprintf(&prompt_arg, "--prompt=%s", prompt);
353
  free(prompt);
354
  if(ret == -1){
355
    error(0, errno, "asprintf");
356
    exit(EXIT_FAILURE);
357
  }
358
  
359
  /* plymouth ask-for-password --prompt="$prompt" */
360
  bret = exec_and_wait(&plymouth_command_pid, plymouth_path,
361
		       (const char *[]){plymouth_path, "ask-for-password", prompt_arg, NULL},
362
		       true, false);
363
  free(prompt_arg);
364
  if(not bret){
365
    if(interrupted_by_signal){
366
      kill_and_wait(plymouth_command_pid);
367
    } else {
368
      exit(EXIT_FAILURE);
369
    }
370
  }
371
  
372
  if(bret){
373
    exit(EXIT_SUCCESS);
374
  }
375
  
376
  const char **plymouthd_argv = NULL;
377
  pid_t pid = get_pid();
378
  if(pid == 0){
379
    error(0, 0, "plymouthd pid not found");
380
  } else {
381
    plymouthd_argv = getargv(pid);
382
  }
383
  if(plymouthd_argv == NULL){
384
    plymouthd_argv = plymouthd_default_argv;
385
  }
386
  
387
  bret = exec_and_wait(NULL, plymouth_path,
388
  		       (const char *[]){plymouth_path, "quit", NULL}, false, false);
389
  if(not bret){
390
    exit(EXIT_FAILURE);
391
  }
392
  bret = exec_and_wait(NULL, plymouthd_path, plymouthd_argv, false, true);
393
  if(not bret){
394
    exit(EXIT_FAILURE);
395
  }
396
  exec_and_wait(NULL, plymouth_path,
397
  		(const char *[]){ plymouth_path, "show-splash", NULL }, false, false);
398
  exit(EXIT_FAILURE);
399
}