getpass.c raw

   1  #define _GNU_SOURCE
   2  #include <stdio.h>
   3  #include <termios.h>
   4  #include <unistd.h>
   5  #include <fcntl.h>
   6  #include <string.h>
   7  
   8  char *getpass(const char *prompt)
   9  {
  10  	int fd;
  11  	struct termios s, t;
  12  	ssize_t l;
  13  	static char password[128];
  14  
  15  	if ((fd = open("/dev/tty", O_RDWR|O_NOCTTY|O_CLOEXEC)) < 0) return 0;
  16  
  17  	tcgetattr(fd, &t);
  18  	s = t;
  19  	t.c_lflag &= ~(ECHO|ISIG);
  20  	t.c_lflag |= ICANON;
  21  	t.c_iflag &= ~(INLCR|IGNCR);
  22  	t.c_iflag |= ICRNL;
  23  	tcsetattr(fd, TCSAFLUSH, &t);
  24  	tcdrain(fd);
  25  
  26  	dprintf(fd, "%s", prompt);
  27  
  28  	l = read(fd, password, sizeof password);
  29  	if (l >= 0) {
  30  		if (l > 0 && password[l-1] == '\n' || l==sizeof password) l--;
  31  		password[l] = 0;
  32  	}
  33  
  34  	tcsetattr(fd, TCSAFLUSH, &s);
  35  
  36  	dprintf(fd, "\n");
  37  	close(fd);
  38  
  39  	return l<0 ? 0 : password;
  40  }
  41