2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41 * Reads a passphrase from /dev/tty with echo turned off. Returns the
42 * passphrase (allocated with xmalloc), being very careful to ensure that
43 * no other userland buffer is storing the password.
46 read_passphrase(const char *prompt, int from_stdin)
48 char buf[1024], *p, ch;
49 struct termios tio, saved_tio;
51 int input, output, echo = 0;
55 output = STDERR_FILENO;
57 input = output = open("/dev/tty", O_RDWR);
60 fatal("You have no controlling tty. Cannot read passphrase.\n");
62 /* block signals, get terminal modes and turn off echo */
64 sigaddset(&nset, SIGINT);
65 sigaddset(&nset, SIGTSTP);
66 (void) sigprocmask(SIG_BLOCK, &nset, &oset);
68 if (tcgetattr(input, &tio) == 0 && (tio.c_lflag & ECHO)) {
71 tio.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHONL);
72 (void) tcsetattr(input, TCSANOW, &tio);
77 (void)write(output, prompt, strlen(prompt));
78 for (p = buf; read(input, &ch, 1) == 1 && ch != '\n';)
79 if (p < buf + sizeof(buf) - 1)
82 (void)write(output, "\n", 1);
84 /* restore terminal modes and allow signals */
86 tcsetattr(input, TCSANOW, &saved_tio);
87 (void) sigprocmask(SIG_SETMASK, &oset, NULL);
92 memset(buf, 0, sizeof(buf));