1 /* $OpenBSD: readpassphrase.c,v 1.22 2010/01/13 10:20:54 dtucker Exp $ */ 2 3 /* 4 * Copyright (c) 2000-2002, 2007 Todd C. Miller <Todd.Miller (at) courtesan.com> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 * 18 * Sponsored in part by the Defense Advanced Research Projects 19 * Agency (DARPA) and Air Force Research Laboratory, Air Force 20 * Materiel Command, USAF, under agreement number F39502-99-1-0512. 21 */ 22 23 /* OPENBSD ORIGINAL: lib/libc/gen/readpassphrase.c */ 24 25 #include "includes.h" 26 27 #ifndef HAVE_READPASSPHRASE 28 29 #include <termios.h> 30 #include <signal.h> 31 #include <ctype.h> 32 #include <fcntl.h> 33 #include <readpassphrase.h> 34 #include <errno.h> 35 #include <string.h> 36 #include <unistd.h> 37 38 #ifdef TCSASOFT 39 # define _T_FLUSH (TCSAFLUSH|TCSASOFT) 40 #else 41 # define _T_FLUSH (TCSAFLUSH) 42 #endif 43 44 /* SunOS 4.x which lacks _POSIX_VDISABLE, but has VDISABLE */ 45 #if !defined(_POSIX_VDISABLE) && defined(VDISABLE) 46 # define _POSIX_VDISABLE VDISABLE 47 #endif 48 49 #ifndef _NSIG 50 # ifdef NSIG 51 # define _NSIG NSIG 52 # else 53 # define _NSIG 128 54 # endif 55 #endif 56 57 static volatile sig_atomic_t signo[_NSIG]; 58 59 static void handler(int); 60 61 char * 62 readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags) 63 { 64 ssize_t nr; 65 int input, output, save_errno, i, need_restart; 66 char ch, *p, *end; 67 struct termios term, oterm; 68 struct sigaction sa, savealrm, saveint, savehup, savequit, saveterm; 69 struct sigaction savetstp, savettin, savettou, savepipe; 70 71 /* I suppose we could alloc on demand in this case (XXX). */ 72 if (bufsiz == 0) { 73 errno = EINVAL; 74 return(NULL); 75 } 76 77 restart: 78 for (i = 0; i < _NSIG; i++) 79 signo[i] = 0; 80 nr = -1; 81 save_errno = 0; 82 need_restart = 0; 83 /* 84 * Read and write to /dev/tty if available. If not, read from 85 * stdin and write to stderr unless a tty is required. 86 */ 87 if ((flags & RPP_STDIN) || 88 (input = output = open(_PATH_TTY, O_RDWR)) == -1) { 89 if (flags & RPP_REQUIRE_TTY) { 90 errno = ENOTTY; 91 return(NULL); 92 } 93 input = STDIN_FILENO; 94 output = STDERR_FILENO; 95 } 96 97 /* 98 * Catch signals that would otherwise cause the user to end 99 * up with echo turned off in the shell. Don't worry about 100 * things like SIGXCPU and SIGVTALRM for now. 101 */ 102 sigemptyset(&sa.sa_mask); 103 sa.sa_flags = 0; /* don't restart system calls */ 104 sa.sa_handler = handler; 105 (void)sigaction(SIGALRM, &sa, &savealrm); 106 (void)sigaction(SIGHUP, &sa, &savehup); 107 (void)sigaction(SIGINT, &sa, &saveint); 108 (void)sigaction(SIGPIPE, &sa, &savepipe); 109 (void)sigaction(SIGQUIT, &sa, &savequit); 110 (void)sigaction(SIGTERM, &sa, &saveterm); 111 (void)sigaction(SIGTSTP, &sa, &savetstp); 112 (void)sigaction(SIGTTIN, &sa, &savettin); 113 (void)sigaction(SIGTTOU, &sa, &savettou); 114 115 /* Turn off echo if possible. */ 116 if (input != STDIN_FILENO && tcgetattr(input, &oterm) == 0) { 117 memcpy(&term, &oterm, sizeof(term)); 118 if (!(flags & RPP_ECHO_ON)) 119 term.c_lflag &= ~(ECHO | ECHONL); 120 #ifdef VSTATUS 121 if (term.c_cc[VSTATUS] != _POSIX_VDISABLE) 122 term.c_cc[VSTATUS] = _POSIX_VDISABLE; 123 #endif 124 (void)tcsetattr(input, _T_FLUSH, &term); 125 } else { 126 memset(&term, 0, sizeof(term)); 127 term.c_lflag |= ECHO; 128 memset(&oterm, 0, sizeof(oterm)); 129 oterm.c_lflag |= ECHO; 130 } 131 132 /* No I/O if we are already backgrounded. */ 133 if (signo[SIGTTOU] != 1 && signo[SIGTTIN] != 1) { 134 if (!(flags & RPP_STDIN)) 135 (void)write(output, prompt, strlen(prompt)); 136 end = buf + bufsiz - 1; 137 p = buf; 138 while ((nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r') { 139 if (p < end) { 140 if ((flags & RPP_SEVENBIT)) 141 ch &= 0x7f; 142 if (isalpha(ch)) { 143 if ((flags & RPP_FORCELOWER)) 144 ch = (char)tolower(ch); 145 if ((flags & RPP_FORCEUPPER)) 146 ch = (char)toupper(ch); 147 } 148 *p++ = ch; 149 } 150 } 151 *p = '\0'; 152 save_errno = errno; 153 if (!(term.c_lflag & ECHO)) 154 (void)write(output, "\n", 1); 155 } 156 157 /* Restore old terminal settings and signals. */ 158 if (memcmp(&term, &oterm, sizeof(term)) != 0) { 159 while (tcsetattr(input, _T_FLUSH, &oterm) == -1 && 160 errno == EINTR) 161 continue; 162 } 163 (void)sigaction(SIGALRM, &savealrm, NULL); 164 (void)sigaction(SIGHUP, &savehup, NULL); 165 (void)sigaction(SIGINT, &saveint, NULL); 166 (void)sigaction(SIGQUIT, &savequit, NULL); 167 (void)sigaction(SIGPIPE, &savepipe, NULL); 168 (void)sigaction(SIGTERM, &saveterm, NULL); 169 (void)sigaction(SIGTSTP, &savetstp, NULL); 170 (void)sigaction(SIGTTIN, &savettin, NULL); 171 (void)sigaction(SIGTTOU, &savettou, NULL); 172 if (input != STDIN_FILENO) 173 (void)close(input); 174 175 /* 176 * If we were interrupted by a signal, resend it to ourselves 177 * now that we have restored the signal handlers. 178 */ 179 for (i = 0; i < _NSIG; i++) { 180 if (signo[i]) { 181 kill(getpid(), i); 182 switch (i) { 183 case SIGTSTP: 184 case SIGTTIN: 185 case SIGTTOU: 186 need_restart = 1; 187 } 188 } 189 } 190 if (need_restart) 191 goto restart; 192 193 if (save_errno) 194 errno = save_errno; 195 return(nr == -1 ? NULL : buf); 196 } 197 198 #if 0 199 char * 200 getpass(const char *prompt) 201 { 202 static char buf[_PASSWORD_LEN + 1]; 203 204 return(readpassphrase(prompt, buf, sizeof(buf), RPP_ECHO_OFF)); 205 } 206 #endif 207 208 static void handler(int s) 209 { 210 211 signo[s] = 1; 212 } 213 #endif /* HAVE_READPASSPHRASE */ 214
