1 /* OPENBSD ORIGINAL: lib/libc/gen/readpassphrase.c */ 2 3 /* $OpenBSD: readpassphrase.c,v 1.16 2003/06/17 21:56:23 millert Exp $ */ 4 5 /* 6 * Copyright (c) 2000-2002 Todd C. Miller <Todd.Miller@courtesan.com> 7 * 8 * Permission to use, copy, modify, and distribute this software for any 9 * purpose with or without fee is hereby granted, provided that the above 10 * copyright notice and this permission notice appear in all copies. 11 * 12 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 13 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 14 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 15 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 16 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 17 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 18 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 19 * 20 * Sponsored in part by the Defense Advanced Research Projects 21 * Agency (DARPA) and Air Force Research Laboratory, Air Force 22 * Materiel Command, USAF, under agreement number F39502-99-1-0512. 23 */ 24 25 #if defined(LIBC_SCCS) && !defined(lint) 26 static const char rcsid[] = "$OpenBSD: readpassphrase.c,v 1.16 2003/06/17 21:56:23 millert Exp $"; 27 #endif /* LIBC_SCCS and not lint */ 28 29 #include "includes.h" 30 31 #ifndef HAVE_READPASSPHRASE 32 33 #include <termios.h> 34 #include <readpassphrase.h> 35 36 #ifdef TCSASOFT 37 # define _T_FLUSH (TCSAFLUSH|TCSASOFT) 38 #else 39 # define _T_FLUSH (TCSAFLUSH) 40 #endif 41 42 /* SunOS 4.x which lacks _POSIX_VDISABLE, but has VDISABLE */ 43 #if !defined(_POSIX_VDISABLE) && defined(VDISABLE) 44 # define _POSIX_VDISABLE VDISABLE 45 #endif 46 47 static volatile sig_atomic_t signo; 48 49 static void handler(int); 50 51 char * 52 readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags) 53 { 54 ssize_t nr; 55 int input, output, save_errno; 56 char ch, *p, *end; 57 struct termios term, oterm; 58 struct sigaction sa, savealrm, saveint, savehup, savequit, saveterm; 59 struct sigaction savetstp, savettin, savettou, savepipe; 60 61 /* I suppose we could alloc on demand in this case (XXX). */ 62 if (bufsiz == 0) { 63 errno = EINVAL; 64 return(NULL); 65 } 66 67 restart: 68 signo = 0; 69 /* 70 * Read and write to /dev/tty if available. If not, read from 71 * stdin and write to stderr unless a tty is required. 72 */ 73 if ((flags & RPP_STDIN) || 74 (input = output = open(_PATH_TTY, O_RDWR)) == -1) { 75 if (flags & RPP_REQUIRE_TTY) { 76 errno = ENOTTY; 77 return(NULL); 78 } 79 input = STDIN_FILENO; 80 output = STDERR_FILENO; 81 } 82 83 /* 84 * Catch signals that would otherwise cause the user to end 85 * up with echo turned off in the shell. Don't worry about 86 * things like SIGXCPU and SIGVTALRM for now. 87 */ 88 sigemptyset(&sa.sa_mask); 89 sa.sa_flags = 0; /* don't restart system calls */ 90 sa.sa_handler = handler; 91 (void)sigaction(SIGALRM, &sa, &savealrm); 92 (void)sigaction(SIGHUP, &sa, &savehup); 93 (void)sigaction(SIGINT, &sa, &saveint); 94 (void)sigaction(SIGPIPE, &sa, &savepipe); 95 (void)sigaction(SIGQUIT, &sa, &savequit); 96 (void)sigaction(SIGTERM, &sa, &saveterm); 97 (void)sigaction(SIGTSTP, &sa, &savetstp); 98 (void)sigaction(SIGTTIN, &sa, &savettin); 99 (void)sigaction(SIGTTOU, &sa, &savettou); 100 101 /* Turn off echo if possible. */ 102 if (input != STDIN_FILENO && tcgetattr(input, &oterm) == 0) { 103 memcpy(&term, &oterm, sizeof(term)); 104 if (!(flags & RPP_ECHO_ON)) 105 term.c_lflag &= ~(ECHO | ECHONL); 106 #ifdef VSTATUS 107 if (term.c_cc[VSTATUS] != _POSIX_VDISABLE) 108 term.c_cc[VSTATUS] = _POSIX_VDISABLE; 109 #endif 110 (void)tcsetattr(input, _T_FLUSH, &term); 111 } else { 112 memset(&term, 0, sizeof(term)); 113 term.c_lflag |= ECHO; 114 memset(&oterm, 0, sizeof(oterm)); 115 oterm.c_lflag |= ECHO; 116 } 117 118 if (!(flags & RPP_STDIN)) 119 (void)write(output, prompt, strlen(prompt)); 120 end = buf + bufsiz - 1; 121 for (p = buf; (nr = read(input, &ch, 1)) == 1 && ch != '\n' && ch != '\r';) { 122 if (p < end) { 123 if ((flags & RPP_SEVENBIT)) 124 ch &= 0x7f; 125 if (isalpha(ch)) { 126 if ((flags & RPP_FORCELOWER)) 127 ch = tolower(ch); 128 if ((flags & RPP_FORCEUPPER)) 129 ch = toupper(ch); 130 } 131 *p++ = ch; 132 } 133 } 134 *p = '\0'; 135 save_errno = errno; 136 if (!(term.c_lflag & ECHO)) 137 (void)write(output, "\n", 1); 138 139 /* Restore old terminal settings and signals. */ 140 if (memcmp(&term, &oterm, sizeof(term)) != 0) 141 (void)tcsetattr(input, _T_FLUSH, &oterm); 142 (void)sigaction(SIGALRM, &savealrm, NULL); 143 (void)sigaction(SIGHUP, &savehup, NULL); 144 (void)sigaction(SIGINT, &saveint, NULL); 145 (void)sigaction(SIGQUIT, &savequit, NULL); 146 (void)sigaction(SIGPIPE, &savepipe, NULL); 147 (void)sigaction(SIGTERM, &saveterm, NULL); 148 (void)sigaction(SIGTSTP, &savetstp, NULL); 149 (void)sigaction(SIGTTIN, &savettin, NULL); 150 if (input != STDIN_FILENO) 151 (void)close(input); 152 153 /* 154 * If we were interrupted by a signal, resend it to ourselves 155 * now that we have restored the signal handlers. 156 */ 157 if (signo) { 158 kill(getpid(), signo); 159 switch (signo) { 160 case SIGTSTP: 161 case SIGTTIN: 162 case SIGTTOU: 163 goto restart; 164 } 165 } 166 167 errno = save_errno; 168 return(nr == -1 ? NULL : buf); 169 } 170 171 #if 0 172 char * 173 getpass(const char *prompt) 174 { 175 static char buf[_PASSWORD_LEN + 1]; 176 177 return(readpassphrase(prompt, buf, sizeof(buf), RPP_ECHO_OFF)); 178 } 179 #endif 180 181 static void handler(int s) 182 { 183 184 signo = s; 185 } 186 #endif /* HAVE_READPASSPHRASE */ 187