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