passphrase.c revision 302295
1/*-
2 * Copyright (c) 2014 Michihiro NAKAJIMA
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
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 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26/*	$OpenBSD: readpassphrase.c,v 1.22 2010/01/13 10:20:54 dtucker Exp $	*/
27/*
28 * Copyright (c) 2000-2002, 2007 Todd C. Miller <Todd.Miller@courtesan.com>
29 *
30 * Permission to use, copy, modify, and distribute this software for any
31 * purpose with or without fee is hereby granted, provided that the above
32 * copyright notice and this permission notice appear in all copies.
33 *
34 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
35 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
36 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
37 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
38 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
39 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
40 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
41 *
42 * Sponsored in part by the Defense Advanced Research Projects
43 * Agency (DARPA) and Air Force Research Laboratory, Air Force
44 * Materiel Command, USAF, under agreement number F39502-99-1-0512.
45 */
46
47/* OPENBSD ORIGINAL: lib/libc/gen/readpassphrase.c */
48
49
50#include "lafe_platform.h"
51__FBSDID("$FreeBSD: stable/10/contrib/libarchive/libarchive_fe/passphrase.c 302295 2016-06-30 12:44:15Z mm $");
52
53#include <errno.h>
54#ifdef HAVE_STDLIB_H
55#include <stdlib.h>
56#endif
57#ifdef HAVE_UNISTD_H
58#include <unistd.h>
59#endif
60#ifdef HAVE_READPASSPHRASE_H
61#include <readpassphrase.h>
62#endif
63
64#include "err.h"
65#include "passphrase.h"
66
67#ifndef HAVE_READPASSPHRASE
68
69#define RPP_ECHO_OFF    0x00		/* Turn off echo (default). */
70#define RPP_ECHO_ON     0x01		/* Leave echo on. */
71#define RPP_REQUIRE_TTY 0x02		/* Fail if there is no tty. */
72#define RPP_FORCELOWER  0x04		/* Force input to lower case. */
73#define RPP_FORCEUPPER  0x08		/* Force input to upper case. */
74#define RPP_SEVENBIT    0x10		/* Strip the high bit from input. */
75#define RPP_STDIN       0x20		/* Read from stdin, not /dev/tty */
76
77
78#if defined(_WIN32) && !defined(__CYGWIN__)
79#include <windows.h>
80
81static char *
82readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags)
83{
84	HANDLE hStdin, hStdout;
85	DWORD mode, rbytes;
86	BOOL success;
87
88	(void)flags;
89
90	hStdin = GetStdHandle(STD_INPUT_HANDLE);
91	if (hStdin == INVALID_HANDLE_VALUE)
92		return (NULL);
93	hStdout = GetStdHandle(STD_OUTPUT_HANDLE);
94	if (hStdout == INVALID_HANDLE_VALUE)
95		return (NULL);
96
97	success = GetConsoleMode(hStdin, &mode);
98	if (!success)
99		return (NULL);
100	mode &= ~ENABLE_ECHO_INPUT;
101	mode |= ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT;
102	success = SetConsoleMode(hStdin, mode);
103	if (!success)
104		return (NULL);
105
106	success = WriteFile(hStdout, prompt, (DWORD)strlen(prompt),
107		NULL, NULL);
108	if (!success)
109		return (NULL);
110	success = ReadFile(hStdin, buf, (DWORD)bufsiz - 1, &rbytes, NULL);
111	if (!success)
112		return (NULL);
113	WriteFile(hStdout, "\r\n", 2, NULL, NULL);
114	buf[rbytes] = '\0';
115	/* Remove trailing carriage return(s). */
116	if (rbytes > 2 && buf[rbytes - 2] == '\r' && buf[rbytes - 1] == '\n')
117		buf[rbytes - 2] = '\0';
118
119	return (buf);
120}
121
122#else /* _WIN32 && !__CYGWIN__ */
123
124#include <assert.h>
125#include <ctype.h>
126#include <fcntl.h>
127#ifdef HAVE_PATHS_H
128#include <paths.h>
129#endif
130#include <signal.h>
131#include <string.h>
132#include <termios.h>
133#include <unistd.h>
134
135#ifdef TCSASOFT
136# define _T_FLUSH	(TCSAFLUSH|TCSASOFT)
137#else
138# define _T_FLUSH	(TCSAFLUSH)
139#endif
140
141/* SunOS 4.x which lacks _POSIX_VDISABLE, but has VDISABLE */
142#if !defined(_POSIX_VDISABLE) && defined(VDISABLE)
143#  define _POSIX_VDISABLE       VDISABLE
144#endif
145
146#define M(a,b) (a > b ? a : b)
147#define MAX_SIGNO M(M(M(SIGALRM, SIGHUP), \
148                      M(SIGINT, SIGPIPE)), \
149                    M(M(SIGQUIT, SIGTERM), \
150                      M(M(SIGTSTP, SIGTTIN), SIGTTOU)))
151
152static volatile sig_atomic_t signo[MAX_SIGNO + 1];
153
154static void
155handler(int s)
156{
157	assert(s <= MAX_SIGNO);
158	signo[s] = 1;
159}
160
161static char *
162readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags)
163{
164	ssize_t nr;
165	int input, output, save_errno, i, need_restart;
166	char ch, *p, *end;
167	struct termios term, oterm;
168	struct sigaction sa, savealrm, saveint, savehup, savequit, saveterm;
169	struct sigaction savetstp, savettin, savettou, savepipe;
170
171	/* I suppose we could alloc on demand in this case (XXX). */
172	if (bufsiz == 0) {
173		errno = EINVAL;
174		return(NULL);
175	}
176
177restart:
178	for (i = 0; i <= MAX_SIGNO; i++)
179		signo[i] = 0;
180	nr = -1;
181	save_errno = 0;
182	need_restart = 0;
183	/*
184	 * Read and write to /dev/tty if available.  If not, read from
185	 * stdin and write to stderr unless a tty is required.
186	 */
187	if ((flags & RPP_STDIN) ||
188	    (input = output = open(_PATH_TTY, O_RDWR)) == -1) {
189		if (flags & RPP_REQUIRE_TTY) {
190			errno = ENOTTY;
191			return(NULL);
192		}
193		input = STDIN_FILENO;
194		output = STDERR_FILENO;
195	}
196
197	/*
198	 * Catch signals that would otherwise cause the user to end
199	 * up with echo turned off in the shell.  Don't worry about
200	 * things like SIGXCPU and SIGVTALRM for now.
201	 */
202	sigemptyset(&sa.sa_mask);
203	sa.sa_flags = 0;		/* don't restart system calls */
204	sa.sa_handler = handler;
205	/* Keep this list in sync with MAX_SIGNO! */
206	(void)sigaction(SIGALRM, &sa, &savealrm);
207	(void)sigaction(SIGHUP, &sa, &savehup);
208	(void)sigaction(SIGINT, &sa, &saveint);
209	(void)sigaction(SIGPIPE, &sa, &savepipe);
210	(void)sigaction(SIGQUIT, &sa, &savequit);
211	(void)sigaction(SIGTERM, &sa, &saveterm);
212	(void)sigaction(SIGTSTP, &sa, &savetstp);
213	(void)sigaction(SIGTTIN, &sa, &savettin);
214	(void)sigaction(SIGTTOU, &sa, &savettou);
215
216	/* Turn off echo if possible. */
217	if (input != STDIN_FILENO && tcgetattr(input, &oterm) == 0) {
218		memcpy(&term, &oterm, sizeof(term));
219		if (!(flags & RPP_ECHO_ON))
220			term.c_lflag &= ~(ECHO | ECHONL);
221#ifdef VSTATUS
222		if (term.c_cc[VSTATUS] != _POSIX_VDISABLE)
223			term.c_cc[VSTATUS] = _POSIX_VDISABLE;
224#endif
225		(void)tcsetattr(input, _T_FLUSH, &term);
226	} else {
227		memset(&term, 0, sizeof(term));
228		term.c_lflag |= ECHO;
229		memset(&oterm, 0, sizeof(oterm));
230		oterm.c_lflag |= ECHO;
231	}
232
233	/* No I/O if we are already backgrounded. */
234	if (signo[SIGTTOU] != 1 && signo[SIGTTIN] != 1) {
235		if (!(flags & RPP_STDIN)) {
236			int r = write(output, prompt, strlen(prompt));
237			(void)r;
238		}
239		end = buf + bufsiz - 1;
240		p = buf;
241		while ((nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r') {
242			if (p < end) {
243				if ((flags & RPP_SEVENBIT))
244					ch &= 0x7f;
245				if (isalpha((unsigned char)ch)) {
246					if ((flags & RPP_FORCELOWER))
247						ch = (char)tolower((unsigned char)ch);
248					if ((flags & RPP_FORCEUPPER))
249						ch = (char)toupper((unsigned char)ch);
250				}
251				*p++ = ch;
252			}
253		}
254		*p = '\0';
255		save_errno = errno;
256		if (!(term.c_lflag & ECHO)) {
257			int r = write(output, "\n", 1);
258			(void)r;
259		}
260	}
261
262	/* Restore old terminal settings and signals. */
263	if (memcmp(&term, &oterm, sizeof(term)) != 0) {
264		while (tcsetattr(input, _T_FLUSH, &oterm) == -1 &&
265		    errno == EINTR)
266			continue;
267	}
268	(void)sigaction(SIGALRM, &savealrm, NULL);
269	(void)sigaction(SIGHUP, &savehup, NULL);
270	(void)sigaction(SIGINT, &saveint, NULL);
271	(void)sigaction(SIGQUIT, &savequit, NULL);
272	(void)sigaction(SIGPIPE, &savepipe, NULL);
273	(void)sigaction(SIGTERM, &saveterm, NULL);
274	(void)sigaction(SIGTSTP, &savetstp, NULL);
275	(void)sigaction(SIGTTIN, &savettin, NULL);
276	(void)sigaction(SIGTTOU, &savettou, NULL);
277	if (input != STDIN_FILENO)
278		(void)close(input);
279
280	/*
281	 * If we were interrupted by a signal, resend it to ourselves
282	 * now that we have restored the signal handlers.
283	 */
284	for (i = 0; i <= MAX_SIGNO; i++) {
285		if (signo[i]) {
286			kill(getpid(), i);
287			switch (i) {
288			case SIGTSTP:
289			case SIGTTIN:
290			case SIGTTOU:
291				need_restart = 1;
292			}
293		}
294	}
295	if (need_restart)
296		goto restart;
297
298	if (save_errno)
299		errno = save_errno;
300	return(nr == -1 ? NULL : buf);
301}
302#endif /* _WIN32 && !__CYGWIN__ */
303#endif /* HAVE_READPASSPHRASE */
304
305char *
306lafe_readpassphrase(const char *prompt, char *buf, size_t bufsiz)
307{
308	char *p;
309
310	p = readpassphrase(prompt, buf, bufsiz, RPP_ECHO_OFF);
311	if (p == NULL) {
312		switch (errno) {
313		case EINTR:
314			break;
315		default:
316			lafe_errc(1, errno, "Couldn't read passphrase");
317			break;
318		}
319	}
320	return (p);
321}
322
323