1 /* getpass.c -- read a password without echo.
2 *
3 * Portions of this code are Copyright (c) 1988, 1993
4 * The Regents of the University of California. 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 * 3. All advertising materials mentioning features or use of this software
15 * must display the following acknowledgement:
16 * This product includes software developed by the University of
17 * California, Berkeley and its contributors.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <h/mh.h>
36 #include <termios.h>
37
38 /* We don't use MAX_PASS here because the maximum password length on a remote
39 POP daemon will have nothing to do with the length on our OS. 256 is
40 arbitrary but hopefully big enough to accommodate everyone. */
41 #define MAX_PASSWORD_LEN 256
42
43 #ifndef TCSANOW
44 #define TCSANOW 0
45 #endif
46
47 char *
nmh_getpass(const char * prompt)48 nmh_getpass(const char *prompt)
49 {
50 struct termios oterm, term;
51 int ch;
52 char *p;
53 FILE *fout, *fin;
54 static char buf[MAX_PASSWORD_LEN + 1];
55 int istty = isatty(fileno(stdin));
56
57 /* Find if stdin is connect to a terminal. If so, read directly from
58 * the terminal, and turn off echo. Otherwise read from stdin.
59 */
60
61 if (!istty || !(fout = fin = fopen("/dev/tty", "w+"))) {
62 fout = stderr;
63 fin = stdin;
64 }
65 else /* Reading directly from terminal here */
66 {
67 (void)tcgetattr(fileno(fin), &oterm);
68 term = oterm; /* Save original info */
69 term.c_lflag &= ~ECHO;
70 (void)fputs(prompt, fout);
71 rewind(fout); /* implied flush */
72 (void)tcsetattr(fileno(fin), TCSANOW, &term);
73 }
74
75 for (p = buf; (ch = getc(fin)) != EOF &&
76 ch != '\n' &&
77 p < buf + MAX_PASSWORD_LEN;)
78 *p++ = ch;
79 *p = '\0';
80
81 if (istty) {
82 (void)tcsetattr(fileno(fin), TCSANOW, &oterm);
83 rewind(fout);
84 (void)fputc('\n', fout);
85 (void)fclose(fin);
86 }
87 return buf;
88 }
89