newlib/libc/unix/getpass.c

   1 #ifndef _NO_GETPASS
   2 /*
   3  * Copyright (c) 1988 The Regents of the University of California.
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 4. Neither the name of the University nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  */
  30
  31 #if defined(LIBC_SCCS) && !defined(lint)
  32 static char sccsid[] = "@(#)getpass.c   5.9 (Berkeley) 5/6/91";
  33 #endif /* LIBC_SCCS and not lint */
  34
  35 #include <stdio.h>
  36 #include <unistd.h>
  37 #include <pwd.h>
  38 #include <sys/termios.h>
  39 #include <sys/signal.h>
  40 #include <_syslist.h>
  41
  42 #ifndef _PATH_PASSWD
  43 #define _PATH_PASSWD            "/etc/passwd"
  44 #endif
  45
  46 #ifndef _PASSWORD_LEN
  47 #define _PASSWORD_LEN           128     /* max length, not counting NULL */
  48 #endif
  49
  50 char *
  51 getpass (prompt)
  52      const char *prompt;
  53 {
  54   struct termios term;
  55   register int ch;
  56   register char *p;
  57   FILE *fp, *outfp;
  58   long omask;
  59   int echo;
  60   static char buf[_PASSWORD_LEN + 1];
  61
  62   /*
  63    * read and write to /dev/tty if possible; else read from
  64    * stdin and write to stderr.
  65    */
  66
  67   if ((outfp = fp = fopen ("/dev/tty", "w+")) == NULL)
  68     {
  69       outfp = stderr;
  70       fp = stdin;
  71     }
  72   /*
  73    * note - blocking signals isn't necessarily the
  74    * right thing, but we leave it for now.
  75    */
  76   omask = sigblock (sigmask (SIGINT) | sigmask (SIGTSTP));
  77   (void) tcgetattr (fileno (fp), &term);
  78   echo = (term.c_lflag & ECHO);
  79   if (echo)
  80     {
  81       term.c_lflag &= ~ECHO;
  82       (void) tcsetattr (fileno (fp), TCSAFLUSH, &term);
  83     }
  84   (void) fputs (prompt, outfp);
  85   rewind (outfp);               /* implied flush */
  86   for (p = buf; (ch = getc (fp)) != EOF && ch != '\n';)
  87     if (p < buf + _PASSWORD_LEN)
  88       *p++ = ch;
  89   *p = '\0';
  90   (void) write (fileno (outfp), "\n", 1);
  91   if (echo)
  92     {
  93       term.c_lflag |= ECHO;
  94       tcsetattr (fileno (fp), TCSAFLUSH, &term);
  95     }
  96   (void) sigsetmask (omask);
  97   if (fp != stdin)
  98     (void) fclose (fp);
  99   return buf;
 100 }
 101 #endif /* !_NO_GETPASS  */