xbps/bin/xbps-rindex/readpassphrase.c

124 lines
4.1 KiB
C

/* $NetBSD: readpassphrase.c,v 1.1 2009/06/07 22:38:47 christos Exp $ */
/*
* Copyright (c) 2000 Todd C. Miller <Todd.Miller@courtesan.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>
#include "defs.h"
#define RPP_ECHO_OFF 0x00 /* Turn off echo (default). */
#define RPP_ECHO_ON 0x01 /* Leave echo on. */
#define RPP_REQUIRE_TTY 0x02 /* Fail if there is no tty. */
#define RPP_FORCELOWER 0x04 /* Force input to lower case. */
#define RPP_FORCEUPPER 0x08 /* Force input to upper case. */
#define RPP_SEVENBIT 0x10 /* Strip the high bit from input. */
char *
readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags)
{
struct termios term, oterm;
char ch, *p, *end;
int input, output;
sigset_t oset, nset;
/* I suppose we could alloc on demand in this case (XXX). */
if (bufsiz == 0) {
errno = EINVAL;
return(NULL);
}
/*
* Read and write to /dev/tty if available. If not, read from
* stdin and write to stderr unless a tty is required.
*/
if ((input = output = open(_PATH_TTY, O_RDWR)) == -1) {
if (flags & RPP_REQUIRE_TTY) {
errno = ENOTTY;
return(NULL);
}
input = STDIN_FILENO;
output = STDERR_FILENO;
}
/*
* We block SIGINT and SIGTSTP so the terminal is not left
* in an inconsistent state (ie: no echo). It would probably
* be better to simply catch these though.
*/
sigemptyset(&nset);
sigaddset(&nset, SIGINT);
sigaddset(&nset, SIGTSTP);
(void)sigprocmask(SIG_BLOCK, &nset, &oset);
/* Turn off echo if possible. */
if (tcgetattr(input, &oterm) == 0) {
memcpy(&term, &oterm, sizeof(term));
if (!(flags & RPP_ECHO_ON) && (term.c_lflag & ECHO))
term.c_lflag &= ~ECHO;
(void)tcsetattr(input, TCSAFLUSH, &term);
} else {
memset(&term, 0, sizeof(term));
memset(&oterm, 0, sizeof(oterm));
}
(void)write(output, prompt, strlen(prompt));
end = buf + bufsiz - 1;
for (p = buf; read(input, &ch, 1) == 1 && ch != '\n' && ch != '\r';) {
if (p < end) {
if ((flags & RPP_SEVENBIT))
ch &= 0x7f;
if (isalpha((unsigned char)ch)) {
if ((flags & RPP_FORCELOWER))
ch = tolower((unsigned char)ch);
if ((flags & RPP_FORCEUPPER))
ch = toupper((unsigned char)ch);
}
*p++ = ch;
}
}
*p = '\0';
if (!(term.c_lflag & ECHO))
(void)write(output, "\n", 1);
/* Restore old terminal settings and signal mask. */
if (memcmp(&term, &oterm, sizeof(term)) != 0)
(void)tcsetattr(input, TCSAFLUSH, &oterm);
(void)sigprocmask(SIG_SETMASK, &oset, NULL);
if (input != STDIN_FILENO)
(void)close(input);
return(buf);
}