readpassphrase.c (5875B)
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@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 "orconfig.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 "ext/tor_readpassphrase.h" 34 #include <errno.h> 35 #include <string.h> 36 #include <unistd.h> 37 38 #ifndef _PATH_TTY 39 # define _PATH_TTY "/dev/tty" 40 #endif 41 42 #ifdef TCSASOFT 43 # define _T_FLUSH (TCSAFLUSH|TCSASOFT) 44 #else 45 # define _T_FLUSH (TCSAFLUSH) 46 #endif 47 48 /* SunOS 4.x which lacks _POSIX_VDISABLE, but has VDISABLE */ 49 #if !defined(_POSIX_VDISABLE) && defined(VDISABLE) 50 # define _POSIX_VDISABLE VDISABLE 51 #endif 52 53 #ifndef _NSIG 54 # ifdef NSIG 55 # define _NSIG NSIG 56 # else 57 # define _NSIG 128 58 # endif 59 #endif 60 61 static volatile sig_atomic_t signo[_NSIG]; 62 63 static void handler(int); 64 65 char * 66 readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags) 67 { 68 ssize_t bytes_written = 0; 69 ssize_t nr; 70 int input, output, save_errno, i, need_restart; 71 char ch, *p, *end; 72 struct termios term, oterm; 73 struct sigaction sa, savealrm, saveint, savehup, savequit, saveterm; 74 struct sigaction savetstp, savettin, savettou, savepipe; 75 76 /* I suppose we could alloc on demand in this case (XXX). */ 77 if (bufsiz == 0) { 78 errno = EINVAL; 79 return(NULL); 80 } 81 82 restart: 83 for (i = 0; i < _NSIG; i++) 84 signo[i] = 0; 85 nr = -1; 86 save_errno = 0; 87 need_restart = 0; 88 /* 89 * Read and write to /dev/tty if available. If not, read from 90 * stdin and write to stderr unless a tty is required. 91 */ 92 if ((flags & RPP_STDIN) || 93 (input = output = open(_PATH_TTY, O_RDWR)) == -1) { 94 if (flags & RPP_REQUIRE_TTY) { 95 errno = ENOTTY; 96 return(NULL); 97 } 98 input = STDIN_FILENO; 99 output = STDERR_FILENO; 100 } 101 102 /* 103 * Catch signals that would otherwise cause the user to end 104 * up with echo turned off in the shell. Don't worry about 105 * things like SIGXCPU and SIGVTALRM for now. 106 */ 107 sigemptyset(&sa.sa_mask); 108 sa.sa_flags = 0; /* don't restart system calls */ 109 sa.sa_handler = handler; 110 (void)sigaction(SIGALRM, &sa, &savealrm); 111 (void)sigaction(SIGHUP, &sa, &savehup); 112 (void)sigaction(SIGINT, &sa, &saveint); 113 (void)sigaction(SIGPIPE, &sa, &savepipe); 114 (void)sigaction(SIGQUIT, &sa, &savequit); 115 (void)sigaction(SIGTERM, &sa, &saveterm); 116 (void)sigaction(SIGTSTP, &sa, &savetstp); 117 (void)sigaction(SIGTTIN, &sa, &savettin); 118 (void)sigaction(SIGTTOU, &sa, &savettou); 119 120 /* Turn off echo if possible. */ 121 if (input != STDIN_FILENO && tcgetattr(input, &oterm) == 0) { 122 memcpy(&term, &oterm, sizeof(term)); 123 if (!(flags & RPP_ECHO_ON)) 124 term.c_lflag &= ~(ECHO | ECHONL); 125 #ifdef VSTATUS 126 if (term.c_cc[VSTATUS] != _POSIX_VDISABLE) 127 term.c_cc[VSTATUS] = _POSIX_VDISABLE; 128 #endif 129 (void)tcsetattr(input, _T_FLUSH, &term); 130 } else { 131 memset(&term, 0, sizeof(term)); 132 term.c_lflag |= ECHO; 133 memset(&oterm, 0, sizeof(oterm)); 134 oterm.c_lflag |= ECHO; 135 } 136 137 /* No I/O if we are already backgrounded. */ 138 if (signo[SIGTTOU] != 1 && signo[SIGTTIN] != 1) { 139 if (!(flags & RPP_STDIN)) 140 bytes_written = write(output, prompt, strlen(prompt)); 141 end = buf + bufsiz - 1; 142 p = buf; 143 while ((nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r') { 144 if (p < end) { 145 #if 0 146 if ((flags & RPP_SEVENBIT)) 147 ch &= 0x7f; 148 if (isalpha(ch)) { 149 if ((flags & RPP_FORCELOWER)) 150 ch = (char)tolower(ch); 151 if ((flags & RPP_FORCEUPPER)) 152 ch = (char)toupper(ch); 153 } 154 #endif 155 *p++ = ch; 156 } 157 } 158 *p = '\0'; 159 save_errno = errno; 160 if (!(term.c_lflag & ECHO)) 161 bytes_written = write(output, "\n", 1); 162 } 163 164 (void) bytes_written; 165 166 /* Restore old terminal settings and signals. */ 167 if (memcmp(&term, &oterm, sizeof(term)) != 0) { 168 while (tcsetattr(input, _T_FLUSH, &oterm) == -1 && 169 errno == EINTR) 170 continue; 171 } 172 (void)sigaction(SIGALRM, &savealrm, NULL); 173 (void)sigaction(SIGHUP, &savehup, NULL); 174 (void)sigaction(SIGINT, &saveint, NULL); 175 (void)sigaction(SIGQUIT, &savequit, NULL); 176 (void)sigaction(SIGPIPE, &savepipe, NULL); 177 (void)sigaction(SIGTERM, &saveterm, NULL); 178 (void)sigaction(SIGTSTP, &savetstp, NULL); 179 (void)sigaction(SIGTTIN, &savettin, NULL); 180 (void)sigaction(SIGTTOU, &savettou, NULL); 181 if (input != STDIN_FILENO) 182 (void)close(input); 183 184 /* 185 * If we were interrupted by a signal, resend it to ourselves 186 * now that we have restored the signal handlers. 187 */ 188 for (i = 0; i < _NSIG; i++) { 189 if (signo[i]) { 190 kill(getpid(), i); 191 switch (i) { 192 case SIGTSTP: 193 case SIGTTIN: 194 case SIGTTOU: 195 need_restart = 1; 196 } 197 } 198 } 199 if (need_restart) 200 goto restart; 201 202 if (save_errno) 203 errno = save_errno; 204 return(nr == -1 ? NULL : buf); 205 } 206 207 #if 0 208 char * 209 getpass(const char *prompt) 210 { 211 static char buf[_PASSWORD_LEN + 1]; 212 213 return(readpassphrase(prompt, buf, sizeof(buf), RPP_ECHO_OFF)); 214 } 215 #endif 216 217 static void handler(int s) 218 { 219 220 signo[s] = 1; 221 } 222 #endif /* HAVE_READPASSPHRASE */