busybox/libbb/bb_askpass.c

/* vi: set sw=4 ts=4: */
/*
 * Ask for a password
 * I use a static buffer in this function.  Plan accordingly.
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include "libbb.h"

/* do nothing signal handler */
static void askpass_timeout(int UNUSED_PARAM ignore)
{
}

char* FAST_FUNC bb_ask_stdin(const char *prompt)
{
	return bb_ask(STDIN_FILENO, 0, prompt);
}
char* FAST_FUNC bb_ask(const int fd, int timeout, const char *prompt)
{
	/* Was static char[BIGNUM] */
	enum { sizeof_passwd = 128 };
	static char *passwd;

	char *ret;
	int i;
	struct sigaction sa, oldsa;
	struct termios tio, oldtio;

	tcgetattr(fd, &oldtio);
	tcflush(fd, TCIFLUSH);
	tio = oldtio;
#ifndef IUCLC
# define IUCLC 0
#endif
	tio.c_iflag &= ~(IUCLC|IXON|IXOFF|IXANY);
	tio.c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL|TOSTOP);
	tcsetattr(fd, TCSANOW, &tio);

	memset(&sa, 0, sizeof(sa));
	/* sa.sa_flags = 0; - no SA_RESTART! */
	/* SIGINT and SIGALRM will interrupt reads below */
	sa.sa_handler = askpass_timeout;
	sigaction(SIGINT, &sa, &oldsa);
	if (timeout) {
		sigaction_set(SIGALRM, &sa);
		alarm(timeout);
	}

	fputs(prompt, stdout);
	fflush_all();

	if (!passwd)
		passwd = xmalloc(sizeof_passwd);
	ret = passwd;
	i = 0;
	while (1) {
		int r = read(fd, &ret[i], 1);
		if (r < 0) {
			/* read is interrupted by timeout or ^C */
			ret = NULL;
			break;
		}
		if (r == 0 /* EOF */
		 || ret[i] == '\r' || ret[i] == '\n' /* EOL */
		 || ++i == sizeof_passwd-1 /* line limit */
		) {
			ret[i] = '\0';
			break;
		}
	}

	if (timeout) {
		alarm(0);
	}
	sigaction_set(SIGINT, &oldsa);
	tcsetattr(fd, TCSANOW, &oldtio);
	bb_putchar('\n');
	fflush_all();
	return ret;
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Ask for a password
4	* I use a static buffer in this function. Plan accordingly.
5	*
6	* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
7	*
8	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
9	*/
10
11	#include "libbb.h"
12
13	/* do nothing signal handler */
14	static void askpass_timeout(int UNUSED_PARAM ignore)
15	{
16	}
17
18	char* FAST_FUNC bb_ask_stdin(const char *prompt)
19	{
20	return bb_ask(STDIN_FILENO, 0, prompt);
21	}
22	char* FAST_FUNC bb_ask(const int fd, int timeout, const char *prompt)
23	{
24	/* Was static char[BIGNUM] */
25	enum { sizeof_passwd = 128 };
26	static char *passwd;
27
28	char *ret;
29	int i;
30	struct sigaction sa, oldsa;
31	struct termios tio, oldtio;
32
33	tcgetattr(fd, &oldtio);
34	tcflush(fd, TCIFLUSH);
35	tio = oldtio;
36	#ifndef IUCLC
37	# define IUCLC 0
38	#endif
39	tio.c_iflag &= ~(IUCLC\|IXON\|IXOFF\|IXANY);
40	tio.c_lflag &= ~(ECHO\|ECHOE\|ECHOK\|ECHONL\|TOSTOP);
41	tcsetattr(fd, TCSANOW, &tio);
42
43	memset(&sa, 0, sizeof(sa));
44	/* sa.sa_flags = 0; - no SA_RESTART! */
45	/* SIGINT and SIGALRM will interrupt reads below */
46	sa.sa_handler = askpass_timeout;
47	sigaction(SIGINT, &sa, &oldsa);
48	if (timeout) {
49	sigaction_set(SIGALRM, &sa);
50	alarm(timeout);
51	}
52
53	fputs(prompt, stdout);
54	fflush_all();
55
56	if (!passwd)
57	passwd = xmalloc(sizeof_passwd);
58	ret = passwd;
59	i = 0;
60	while (1) {
61	int r = read(fd, &ret[i], 1);
62	if (r < 0) {
63	/* read is interrupted by timeout or ^C */
64	ret = NULL;
65	break;
66	}
67	if (r == 0 /* EOF */
68	\|\| ret[i] == '\r' \|\| ret[i] == '\n' /* EOL */
69	\|\| ++i == sizeof_passwd-1 /* line limit */
70	) {
71	ret[i] = '\0';
72	break;
73	}
74	}
75
76	if (timeout) {
77	alarm(0);
78	}
79	sigaction_set(SIGINT, &oldsa);
80	tcsetattr(fd, TCSANOW, &oldtio);
81	bb_putchar('\n');
82	fflush_all();
83	return ret;
84	}