1 /* $OpenBSD: readpassphrase.c,v 1.18 2005/08/08 08:05:34 espie Exp $ */ 2 3 /* 4 * Copyright (c) 2000-2002 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; 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; 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 signo = 0; 71 /* 72 * Read and write to /dev/tty if available. If not, read from 73 * stdin and write to stderr unless a tty is required. 74 */ 75 if ((flags & RPP_STDIN) || 76 (input = output = open(_PATH_TTY, O_RDWR)) == -1) { 77 if (flags & RPP_REQUIRE_TTY) { 78 errno = ENOTTY; 79 return(NULL); 80 } 81 input = STDIN_FILENO; 82 output = STDERR_FILENO; 83 } 84 85 /* 86 * Catch signals that would otherwise cause the user to end 87 * up with echo turned off in the shell. Don't worry about 88 * things like SIGXCPU and SIGVTALRM for now. 89 */ 90 sigemptyset(&sa.sa_mask); 91 sa.sa_flags = 0; /* don't restart system calls */ 92 sa.sa_handler = handler; 93 (void)sigaction(SIGALRM, &sa, &savealrm); 94 (void)sigaction(SIGHUP, &sa, &savehup); 95 (void)sigaction(SIGINT, &sa, &saveint); 96 (void)sigaction(SIGPIPE, &sa, &savepipe); 97 (void)sigaction(SIGQUIT, &sa, &savequit); 98 (void)sigaction(SIGTERM, &sa, &saveterm); 99 (void)sigaction(SIGTSTP, &sa, &savetstp); 100 (void)sigaction(SIGTTIN, &sa, &savettin); 101 (void)sigaction(SIGTTOU, &sa, &savettou); 102 103 /* Turn off echo if possible. */ 104 if (input != STDIN_FILENO && tcgetattr(input, &oterm) == 0) { 105 memcpy(&term, &oterm, sizeof(term)); 106 if (!(flags & RPP_ECHO_ON)) 107 term.c_lflag &= ~(ECHO | ECHONL); 108 #ifdef VSTATUS 109 if (term.c_cc[VSTATUS] != _POSIX_VDISABLE) 110 term.c_cc[VSTATUS] = _POSIX_VDISABLE; 111 #endif 112 (void)tcsetattr(input, _T_FLUSH, &term); 113 } else { 114 memset(&term, 0, sizeof(term)); 115 term.c_lflag |= ECHO; 116 memset(&oterm, 0, sizeof(oterm)); 117 oterm.c_lflag |= ECHO; 118 } 119 120 if (!(flags & RPP_STDIN)) 121 (void)write(output, prompt, strlen(prompt)); 122 end = buf + bufsiz - 1; 123 for (p = buf; (nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r';) { 124 if (p < end) { 125 if ((flags & RPP_SEVENBIT)) 126 ch &= 0x7f; 127 if (isalpha(ch)) { 128 if ((flags & RPP_FORCELOWER)) 129 ch = tolower(ch); 130 if ((flags & RPP_FORCEUPPER)) 131 ch = toupper(ch); 132 } 133 *p++ = ch; 134 } 135 } 136 *p = '\0'; 137 save_errno = errno; 138 if (!(term.c_lflag & ECHO)) 139 (void)write(output, "\n", 1); 140 141 /* Restore old terminal settings and signals. */ 142 if (memcmp(&term, &oterm, sizeof(term)) != 0) { 143 while (tcsetattr(input, _T_FLUSH, &oterm) == -1 && 144 errno == EINTR) 145 continue; 146 } 147 (void)sigaction(SIGALRM, &savealrm, NULL); 148 (void)sigaction(SIGHUP, &savehup, NULL); 149 (void)sigaction(SIGINT, &saveint, NULL); 150 (void)sigaction(SIGQUIT, &savequit, NULL); 151 (void)sigaction(SIGPIPE, &savepipe, NULL); 152 (void)sigaction(SIGTERM, &saveterm, NULL); 153 (void)sigaction(SIGTSTP, &savetstp, NULL); 154 (void)sigaction(SIGTTIN, &savettin, NULL); 155 if (input != STDIN_FILENO) 156 (void)close(input); 157 158 /* 159 * If we were interrupted by a signal, resend it to ourselves 160 * now that we have restored the signal handlers. 161 */ 162 if (signo) { 163 kill(getpid(), signo); 164 switch (signo) { 165 case SIGTSTP: 166 case SIGTTIN: 167 case SIGTTOU: 168 goto restart; 169 } 170 } 171 172 errno = save_errno; 173 return(nr == -1 ? NULL : buf); 174 } 175 176 #if 0 177 char * 178 getpass(const char *prompt) 179 { 180 static char buf[_PASSWORD_LEN + 1]; 181 182 return(readpassphrase(prompt, buf, sizeof(buf), RPP_ECHO_OFF)); 183 } 184 #endif 185 186 static void handler(int s) 187 { 188 189 signo = s; 190 } 191 #endif /* HAVE_READPASSPHRASE */ 192