1/* $OpenBSD: readpassphrase.c,v 1.12 2001/12/15 05:41:00 millert Exp $ */ 2 3/* 4 * Copyright (c) 2000 Todd C. Miller <Todd.Miller@courtesan.com> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 19 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 20 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 21 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 23 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 24 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 25 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 26 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 27 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#if defined(LIBC_SCCS) && !defined(lint) 31static const char rcsid[] = "$OpenBSD: readpassphrase.c,v 1.12 2001/12/15 05:41:00 millert Exp $"; 32#endif /* LIBC_SCCS and not lint */ 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: src/lib/libc/gen/readpassphrase.c,v 1.6 2002/03/09 03:16:41 green Exp $"); 35 36#include "xlocale_private.h" 37 38#include "namespace.h" 39#include <ctype.h> 40#include <errno.h> 41#include <fcntl.h> 42#include <paths.h> 43#include <pwd.h> 44#include <signal.h> 45#include <string.h> 46#include <termios.h> 47#include <unistd.h> 48#include <readpassphrase.h> 49#include "un-namespace.h" 50 51static volatile sig_atomic_t signo; 52 53static void handler(int); 54 55char * 56readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags) 57{ 58 ssize_t nr; 59 int input, output, save_errno; 60 char ch, *p, *end; 61 struct termios term, oterm; 62 struct sigaction sa, saveint, savehup, savequit, saveterm; 63 struct sigaction savetstp, savettin, savettou; 64 locale_t loc = __current_locale(); 65 66 /* I suppose we could alloc on demand in this case (XXX). */ 67 if (bufsiz == 0) { 68 errno = EINVAL; 69 return(NULL); 70 } 71 72restart: 73 /* 74 * Read and write to /dev/tty if available. If not, read from 75 * stdin and write to stderr unless a tty is required. 76 */ 77 if ((input = output = _open(_PATH_TTY, O_RDWR)) == -1) { 78 if (flags & RPP_REQUIRE_TTY) { 79 errno = ENOTTY; 80 return(NULL); 81 } 82 input = STDIN_FILENO; 83 output = STDERR_FILENO; 84 } 85 86 /* 87 * Catch signals that would otherwise cause the user to end 88 * up with echo turned off in the shell. Don't worry about 89 * things like SIGALRM and SIGPIPE for now. 90 */ 91 sigemptyset(&sa.sa_mask); 92 sa.sa_flags = 0; /* don't restart system calls */ 93 sa.sa_handler = handler; 94 (void)_sigaction(SIGINT, &sa, &saveint); 95 (void)_sigaction(SIGHUP, &sa, &savehup); 96 (void)_sigaction(SIGQUIT, &sa, &savequit); 97 (void)_sigaction(SIGTERM, &sa, &saveterm); 98 (void)_sigaction(SIGTSTP, &sa, &savetstp); 99 (void)_sigaction(SIGTTIN, &sa, &savettin); 100 (void)_sigaction(SIGTTOU, &sa, &savettou); 101 102 /* Turn off echo if possible. */ 103 if (tcgetattr(input, &oterm) == 0) { 104 memcpy(&term, &oterm, sizeof(term)); 105 if (!(flags & RPP_ECHO_ON)) 106 term.c_lflag &= ~(ECHO | ECHONL); 107 if (term.c_cc[VSTATUS] != _POSIX_VDISABLE) 108 term.c_cc[VSTATUS] = _POSIX_VDISABLE; 109 (void)tcsetattr(input, TCSAFLUSH|TCSASOFT, &term); 110 } else { 111 memset(&term, 0, sizeof(term)); 112 memset(&oterm, 0, sizeof(oterm)); 113 } 114 115 (void)_write(output, prompt, strlen(prompt)); 116 end = buf + bufsiz - 1; 117 for (p = buf; (nr = _read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r';) { 118 if (p < end) { 119 if ((flags & RPP_SEVENBIT)) 120 ch &= 0x7f; 121 if (isalpha_l(ch, loc)) { 122 if ((flags & RPP_FORCELOWER)) 123 ch = tolower_l(ch, loc); 124 if ((flags & RPP_FORCEUPPER)) 125 ch = toupper_l(ch, loc); 126 } 127 *p++ = ch; 128 } 129 } 130 *p = '\0'; 131 save_errno = errno; 132 if (!(term.c_lflag & ECHO)) 133 (void)_write(output, "\n", 1); 134 135 /* Restore old terminal settings and signals. */ 136 if (memcmp(&term, &oterm, sizeof(term)) != 0) 137 (void)tcsetattr(input, TCSANOW|TCSASOFT, &oterm); 138 (void)_sigaction(SIGINT, &saveint, NULL); 139 (void)_sigaction(SIGHUP, &savehup, NULL); 140 (void)_sigaction(SIGQUIT, &savequit, NULL); 141 (void)_sigaction(SIGTERM, &saveterm, NULL); 142 (void)_sigaction(SIGTSTP, &savetstp, NULL); 143 (void)_sigaction(SIGTTIN, &savettin, NULL); 144 (void)_sigaction(SIGTTOU, &savettou, NULL); 145 if (input != STDIN_FILENO) 146 (void)_close(input); 147 148 /* 149 * If we were interrupted by a signal, resend it to ourselves 150 * now that we have restored the signal handlers. 151 */ 152 if (signo) { 153 kill(getpid(), signo); 154 switch (signo) { 155 case SIGTSTP: 156 case SIGTTIN: 157 case SIGTTOU: 158 signo = 0; 159 goto restart; 160 } 161 } 162 163 errno = save_errno; 164 return(nr == -1 ? NULL : buf); 165} 166 167char * 168getpass(const char *prompt) 169{ 170 const size_t bufsiz = _PASSWORD_LEN + 1; 171 static char *buf = NULL; 172 173 if (buf == NULL) { 174 buf = malloc(bufsiz); 175 if (buf == NULL) { 176 return NULL; 177 } 178 } 179 180 if (readpassphrase(prompt, buf, bufsiz, RPP_ECHO_OFF) == NULL) { 181 buf[0] = '\0'; 182 } 183 return buf; 184} 185 186static void handler(int s) 187{ 188 189 signo = s; 190} 191