readpassphrase.c revision 98937
1141240Snjl/* $OpenBSD: readpassphrase.c,v 1.12 2001/12/15 05:41:00 millert Exp $ */ 2141240Snjl 3141240Snjl/* 4141240Snjl * Copyright (c) 2000 Todd C. Miller <Todd.Miller@courtesan.com> 5141240Snjl * All rights reserved. 6141240Snjl * 7141240Snjl * Redistribution and use in source and binary forms, with or without 8141240Snjl * modification, are permitted provided that the following conditions 9141240Snjl * are met: 10141240Snjl * 1. Redistributions of source code must retain the above copyright 11141240Snjl * notice, this list of conditions and the following disclaimer. 12141240Snjl * 2. Redistributions in binary form must reproduce the above copyright 13141240Snjl * notice, this list of conditions and the following disclaimer in the 14141240Snjl * documentation and/or other materials provided with the distribution. 15141240Snjl * 3. The name of the author may not be used to endorse or promote products 16141240Snjl * derived from this software without specific prior written permission. 17141240Snjl * 18141240Snjl * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 19141240Snjl * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 20141240Snjl * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 21141240Snjl * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 22141240Snjl * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 23141240Snjl * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 24141240Snjl * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 25141240Snjl * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 26141240Snjl * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 27141240Snjl * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28141240Snjl */ 29141240Snjl 30141240Snjl#if defined(LIBC_SCCS) && !defined(lint) 31141240Snjlstatic const char rcsid[] = "$OpenBSD: readpassphrase.c,v 1.12 2001/12/15 05:41:00 millert Exp $"; 32141240Snjl#endif /* LIBC_SCCS and not lint */ 33141240Snjl 34141240Snjl#include "includes.h" 35141240Snjl 36141240Snjl#ifndef HAVE_READPASSPHRASE 37141240Snjl 38141240Snjl#include <termios.h> 39141240Snjl#include <readpassphrase.h> 40141240Snjl 41141240Snjl#ifdef TCSASOFT 42141240Snjl# define _T_FLUSH (TCSAFLUSH|TCSASOFT) 43141814Snjl#else 44141240Snjl# define _T_FLUSH (TCSAFLUSH) 45141240Snjl#endif 46141240Snjl 47141240Snjl/* SunOS 4.x which lacks _POSIX_VDISABLE, but has VDISABLE */ 48141240Snjl#if !defined(_POSIX_VDISABLE) && defined(VDISABLE) 49141240Snjl# define _POSIX_VDISABLE VDISABLE 50141240Snjl#endif 51141240Snjl 52141240Snjlstatic volatile sig_atomic_t signo; 53141240Snjl 54141240Snjlstatic void handler(int); 55141240Snjl 56141240Snjlchar * 57141240Snjlreadpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags) 58141240Snjl{ 59141240Snjl ssize_t nr; 60141923Snjl int input, output, save_errno; 61141923Snjl char ch, *p, *end; 62141923Snjl struct termios term, oterm; 63141923Snjl struct sigaction sa, saveint, savehup, savequit, saveterm; 64141413Snjl struct sigaction savetstp, savettin, savettou; 65141240Snjl 66141240Snjl /* I suppose we could alloc on demand in this case (XXX). */ 67141240Snjl if (bufsiz == 0) { 68141240Snjl errno = EINVAL; 69141240Snjl return(NULL); 70141240Snjl } 71141240Snjl 72141240Snjlrestart: 73141240Snjl /* 74141240Snjl * Read and write to /dev/tty if available. If not, read from 75141240Snjl * stdin and write to stderr unless a tty is required. 76141240Snjl */ 77141240Snjl if ((input = output = open(_PATH_TTY, O_RDWR)) == -1) { 78141240Snjl if (flags & RPP_REQUIRE_TTY) { 79141240Snjl errno = ENOTTY; 80141240Snjl return(NULL); 81141240Snjl } 82141240Snjl input = STDIN_FILENO; 83141240Snjl output = STDERR_FILENO; 84141240Snjl } 85141413Snjl 86141240Snjl /* 87141413Snjl * Catch signals that would otherwise cause the user to end 88141413Snjl * up with echo turned off in the shell. Don't worry about 89141413Snjl * things like SIGALRM and SIGPIPE for now. 90141413Snjl */ 91141240Snjl sigemptyset(&sa.sa_mask); 92141240Snjl sa.sa_flags = 0; /* don't restart system calls */ 93141240Snjl sa.sa_handler = handler; 94141240Snjl (void)sigaction(SIGINT, &sa, &saveint); 95141240Snjl (void)sigaction(SIGHUP, &sa, &savehup); 96141240Snjl (void)sigaction(SIGQUIT, &sa, &savequit); 97141240Snjl (void)sigaction(SIGTERM, &sa, &saveterm); 98141240Snjl (void)sigaction(SIGTSTP, &sa, &savetstp); 99141240Snjl (void)sigaction(SIGTTIN, &sa, &savettin); 100141240Snjl (void)sigaction(SIGTTOU, &sa, &savettou); 101141240Snjl 102141240Snjl /* Turn off echo if possible. */ 103141240Snjl if (tcgetattr(input, &oterm) == 0) { 104141240Snjl memcpy(&term, &oterm, sizeof(term)); 105141240Snjl if (!(flags & RPP_ECHO_ON)) 106141240Snjl term.c_lflag &= ~(ECHO | ECHONL); 107141240Snjl#ifdef VSTATUS 108141240Snjl if (term.c_cc[VSTATUS] != _POSIX_VDISABLE) 109141240Snjl term.c_cc[VSTATUS] = _POSIX_VDISABLE; 110141240Snjl#endif 111141240Snjl (void)tcsetattr(input, _T_FLUSH, &term); 112141240Snjl } else { 113141240Snjl memset(&term, 0, sizeof(term)); 114141240Snjl memset(&oterm, 0, sizeof(oterm)); 115141240Snjl } 116141240Snjl 117141240Snjl (void)write(output, prompt, strlen(prompt)); 118141240Snjl end = buf + bufsiz - 1; 119141240Snjl for (p = buf; (nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r';) { 120141240Snjl if (p < end) { 121141240Snjl if ((flags & RPP_SEVENBIT)) 122141240Snjl ch &= 0x7f; 123141240Snjl if (isalpha(ch)) { 124141240Snjl if ((flags & RPP_FORCELOWER)) 125141923Snjl ch = tolower(ch); 126141240Snjl if ((flags & RPP_FORCEUPPER)) 127141240Snjl ch = toupper(ch); 128141240Snjl } 129141240Snjl *p++ = ch; 130141240Snjl } 131141240Snjl } 132141240Snjl *p = '\0'; 133141240Snjl save_errno = errno; 134141240Snjl if (!(term.c_lflag & ECHO)) 135141240Snjl (void)write(output, "\n", 1); 136141240Snjl 137141240Snjl /* Restore old terminal settings and signals. */ 138141240Snjl if (memcmp(&term, &oterm, sizeof(term)) != 0) 139141240Snjl (void)tcsetattr(input, _T_FLUSH, &oterm); 140141240Snjl (void)sigaction(SIGINT, &saveint, NULL); 141141240Snjl (void)sigaction(SIGHUP, &savehup, NULL); 142141240Snjl (void)sigaction(SIGQUIT, &savequit, NULL); 143141240Snjl (void)sigaction(SIGTERM, &saveterm, NULL); 144141240Snjl (void)sigaction(SIGTSTP, &savetstp, NULL); 145141240Snjl (void)sigaction(SIGTTIN, &savettin, NULL); 146141240Snjl (void)sigaction(SIGTTOU, &savettou, NULL); 147141240Snjl if (input != STDIN_FILENO) 148141240Snjl (void)close(input); 149141240Snjl 150141240Snjl /* 151141240Snjl * If we were interrupted by a signal, resend it to ourselves 152141240Snjl * now that we have restored the signal handlers. 153141240Snjl */ 154141240Snjl if (signo) { 155141240Snjl kill(getpid(), signo); 156141240Snjl switch (signo) { 157141240Snjl case SIGTSTP: 158141240Snjl case SIGTTIN: 159141240Snjl case SIGTTOU: 160141240Snjl signo = 0; 161141240Snjl goto restart; 162141240Snjl } 163141240Snjl } 164141240Snjl 165141240Snjl errno = save_errno; 166141240Snjl return(nr == -1 ? NULL : buf); 167141240Snjl} 168141240Snjl 169141240Snjl#if 0 170141240Snjlchar * 171141240Snjlgetpass(const char *prompt) 172141240Snjl{ 173141240Snjl static char buf[_PASSWORD_LEN + 1]; 174141240Snjl 175141240Snjl return(readpassphrase(prompt, buf, sizeof(buf), RPP_ECHO_OFF)); 176141240Snjl} 177141240Snjl#endif 178141814Snjl 179141814Snjlstatic void handler(int s) 180141240Snjl{ 181141240Snjl signo = s; 182141240Snjl} 183141814Snjl#endif /* HAVE_READPASSPHRASE */ 184141814Snjl