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