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  • Committer: Teddy Hogeborn
  • Date: 2010-10-03 01:38:05 UTC
  • mfrom: (24.1.170 mandos)
  • Revision ID: teddy@fukt.bsnet.se-20101003013805-ojt18455zatp2ewh
Merge from Björn.

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 * Contact the authors at <mandos@fukt.bsnet.se>.
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 */
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#define _GNU_SOURCE             /* getline(), asprintf() */
 
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#define _GNU_SOURCE             /* getline() */
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#include <termios.h>            /* struct termios, tcsetattr(),
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                                   TCSAFLUSH, tcgetattr(), ECHO */
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#include <unistd.h>             /* struct termios, tcsetattr(),
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                                   STDIN_FILENO, TCSAFLUSH,
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                                   tcgetattr(), ECHO, readlink() */
 
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                                   tcgetattr(), ECHO */
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#include <signal.h>             /* sig_atomic_t, raise(), struct
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                                   sigaction, sigemptyset(),
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                                   sigaction(), sigaddset(), SIGINT,
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                                   SIGQUIT, SIGHUP, SIGTERM,
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                                   raise() */
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#include <stddef.h>             /* NULL, size_t, ssize_t */
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#include <sys/types.h>          /* ssize_t, struct dirent, pid_t,
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                                   ssize_t, open() */
 
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#include <sys/types.h>          /* ssize_t */
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#include <stdlib.h>             /* EXIT_SUCCESS, EXIT_FAILURE,
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                                   getenv(), free() */
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#include <dirent.h>             /* scandir(), alphasort() */
 
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                                   getenv() */
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#include <stdio.h>              /* fprintf(), stderr, getline(),
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                                   stdin, feof(), fputc()
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                                */
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#include <error.h>              /* error() */
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#include <iso646.h>             /* or, not */
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#include <stdbool.h>            /* bool, false, true */
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#include <inttypes.h>           /* strtoumax() */
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#include <sys/stat.h>           /* struct stat, lstat(), open() */
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#include <string.h>             /* strlen, rindex, memcmp */
 
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#include <string.h>             /* strlen, rindex */
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#include <argp.h>               /* struct argp_option, struct
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                                   argp_state, struct argp,
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                                   argp_parse(), error_t,
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                                   ARGP_ERR_UNKNOWN */
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#include <sysexits.h>           /* EX_SOFTWARE, EX_OSERR,
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                                   EX_UNAVAILABLE, EX_IOERR, EX_OK */
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#include <fcntl.h>              /* open() */
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volatile sig_atomic_t quit_now = 0;
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int signal_received;
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const char *argp_program_version = "password-prompt " VERSION;
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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/* Needed for conflict resolution */
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const char plymouth_name[] = "plymouthd";
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const char plymouth_alt_name[] = "plymouthd";
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static void termination_handler(int signum){
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  if(quit_now){
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    return;
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  signal_received = signum;
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}
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bool conflict_detection(void){
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  /* plymouth conflicts with password-prompt since both want to read
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     from the terminal.  Password-prompt will exit if it detects
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     plymouth since plymouth performs the same functionality.
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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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    int cl_fd;
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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'
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         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 *cmdline_filename;
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    ret = asprintf(&cmdline_filename, "/proc/%s/cmdline", 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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    /* 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 0;
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    }
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    char *cmdline = NULL;
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    {
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      size_t cmdline_len = 0;
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      size_t cmdline_allocated = 0;
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      char *tmp;
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      const size_t blocksize = 1024;
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      ssize_t sret;
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      do {
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        /* Allocate more space? */
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        if(cmdline_len + blocksize + 1 > cmdline_allocated){
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          tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
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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 0;
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          }
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          cmdline = tmp;
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          cmdline_allocated += blocksize;
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        }
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        /* Read data */
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        sret = read(cl_fd, cmdline + cmdline_len,
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                    cmdline_allocated - cmdline_len);
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        if(sret == -1){
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          error(0, errno, "read");
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          free(cmdline);
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          close(cl_fd);
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          return 0;
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        }
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        cmdline_len += (size_t)sret;
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      } while(sret != 0);
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      ret = close(cl_fd);
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      if(ret == -1){
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        error(0, errno, "close");
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        free(cmdline);
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        return 0;
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      }
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      cmdline[cmdline_len] = '\0'; /* Make sure it is terminated */
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    }
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    /* we now have cmdline */
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    /* get basename */
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    char *cmdline_base = strrchr(cmdline, '/');
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    if(cmdline_base != NULL){
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      cmdline_base += 1;                /* skip the slash */
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    } else {
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      cmdline_base = cmdline;
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    }
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    if((strcmp(cmdline_base, plymouth_name) != 0)
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       and (strcmp(cmdline_base, plymouth_alt_name) != 0)){
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      free(cmdline);
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      return 0;
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    }
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    free(cmdline);
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    return 1;
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  }
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  struct dirent **direntries;
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  int ret;
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  ret = scandir("/proc", &direntries, is_plymouth, alphasort);
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  if (ret == -1){
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    error(1, errno, "scandir");
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  }
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  return ret > 0;
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}
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int main(int argc, char **argv){
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  ssize_t sret;
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  int ret;
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  if(debug){
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    fprintf(stderr, "Starting %s\n", argv[0]);
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  }
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  if (conflict_detection()){
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    if(debug){
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      fprintf(stderr, "Stopping %s because of conflict", argv[0]);
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    }
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    return EXIT_FAILURE;
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  }
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  if(debug){
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    fprintf(stderr, "Storing current terminal attributes\n");
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  }