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 <readpassphrase.h> 31 32 #ifdef TCSASOFT 33 # define _T_FLUSH (TCSAFLUSH|TCSASOFT) 34 #else 35 # define _T_FLUSH (TCSAFLUSH) 36 #endif 37 38 /* SunOS 4.x which lacks _POSIX_VDISABLE, but has VDISABLE */ 39 #if !defined(_POSIX_VDISABLE) && defined(VDISABLE) 40 # define _POSIX_VDISABLE VDISABLE 41 #endif 42 43 static volatile sig_atomic_t signo; 44 45 static void handler(int); 46 47 char * 48 readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags) 49 { 50 ssize_t nr; 51 int input, output, save_errno; 52 char ch, *p, *end; 53 struct termios term, oterm; 54 struct sigaction sa, savealrm, saveint, savehup, savequit, saveterm; 55 struct sigaction savetstp, savettin, savettou, savepipe; 56 57 /* I suppose we could alloc on demand in this case (XXX). */ 58 if (bufsiz == 0) { 59 errno = EINVAL; 60 return(NULL); 61 } 62 63 restart: 64 signo = 0; 65 /* 66 * Read and write to /dev/tty if available. If not, read from 67 * stdin and write to stderr unless a tty is required. 68 */ 69 if ((flags & RPP_STDIN) || 70 (input = output = open(_PATH_TTY, O_RDWR)) == -1) { 71 if (flags & RPP_REQUIRE_TTY) { 72 errno = ENOTTY; 73 return(NULL); 74 } 75 input = STDIN_FILENO; 76 output = STDERR_FILENO; 77 } 78 79 /* 80 * Catch signals that would otherwise cause the user to end 81 * up with echo turned off in the shell. Don't worry about 82 * things like SIGXCPU and SIGVTALRM for now. 83 */ 84 sigemptyset(&sa.sa_mask); 85 sa.sa_flags = 0; /* don't restart system calls */ 86 sa.sa_handler = handler; 87 (void)sigaction(SIGALRM, &sa, &savealrm); 88 (void)sigaction(SIGHUP, &sa, &savehup); 89 (void)sigaction(SIGINT, &sa, &saveint); 90 (void)sigaction(SIGPIPE, &sa, &savepipe); 91 (void)sigaction(SIGQUIT, &sa, &savequit); 92 (void)sigaction(SIGTERM, &sa, &saveterm); 93 (void)sigaction(SIGTSTP, &sa, &savetstp); 94 (void)sigaction(SIGTTIN, &sa, &savettin); 95 (void)sigaction(SIGTTOU, &sa, &savettou); 96 97 /* Turn off echo if possible. */ 98 if (input != STDIN_FILENO && tcgetattr(input, &oterm) == 0) { 99 memcpy(&term, &oterm, sizeof(term)); 100 if (!(flags & RPP_ECHO_ON)) 101 term.c_lflag &= ~(ECHO | ECHONL); 102 #ifdef VSTATUS 103 if (term.c_cc[VSTATUS] != _POSIX_VDISABLE) 104 term.c_cc[VSTATUS] = _POSIX_VDISABLE; 105 #endif 106 (void)tcsetattr(input, _T_FLUSH, &term); 107 } else { 108 memset(&term, 0, sizeof(term)); 109 term.c_lflag |= ECHO; 110 memset(&oterm, 0, sizeof(oterm)); 111 oterm.c_lflag |= ECHO; 112 } 113 114 if (!(flags & RPP_STDIN)) 115 (void)write(output, prompt, strlen(prompt)); 116 end = buf + bufsiz - 1; 117 for (p = buf; (nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r';) { 118 if (p < end) { 119 if ((flags & RPP_SEVENBIT)) 120 ch &= 0x7f; 121 if (isalpha(ch)) { 122 if ((flags & RPP_FORCELOWER)) 123 ch = tolower(ch); 124 if ((flags & RPP_FORCEUPPER)) 125 ch = toupper(ch); 126 } 127 *p++ = ch; 128 } 129 } 130 *p = '\0'; 131 save_errno = errno; 132 if (!(term.c_lflag & ECHO)) 133 (void)write(output, "\n", 1); 134 135 /* Restore old terminal settings and signals. */ 136 if (memcmp(&term, &oterm, sizeof(term)) != 0) { 137 while (tcsetattr(input, _T_FLUSH, &oterm) == -1 && 138 errno == EINTR) 139 continue; 140 } 141 (void)sigaction(SIGALRM, &savealrm, NULL); 142 (void)sigaction(SIGHUP, &savehup, NULL); 143 (void)sigaction(SIGINT, &saveint, NULL); 144 (void)sigaction(SIGQUIT, &savequit, NULL); 145 (void)sigaction(SIGPIPE, &savepipe, NULL); 146 (void)sigaction(SIGTERM, &saveterm, NULL); 147 (void)sigaction(SIGTSTP, &savetstp, NULL); 148 (void)sigaction(SIGTTIN, &savettin, NULL); 149 if (input != STDIN_FILENO) 150 (void)close(input); 151 152 /* 153 * If we were interrupted by a signal, resend it to ourselves 154 * now that we have restored the signal handlers. 155 */ 156 if (signo) { 157 kill(getpid(), signo); 158 switch (signo) { 159 case SIGTSTP: 160 case SIGTTIN: 161 case SIGTTOU: 162 goto restart; 163 } 164 } 165 166 errno = save_errno; 167 return(nr == -1 ? NULL : buf); 168 } 169 170 #if 0 171 char * 172 getpass(const char *prompt) 173 { 174 static char buf[_PASSWORD_LEN + 1]; 175 176 return(readpassphrase(prompt, buf, sizeof(buf), RPP_ECHO_OFF)); 177 } 178 #endif 179 180 static void handler(int s) 181 { 182 183 signo = s; 184 } 185 #endif /* HAVE_READPASSPHRASE */ 186