1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * Copyright (c) 2001 Markus Friedl. All rights reserved. 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without 5*0Sstevel@tonic-gate * modification, are permitted provided that the following conditions 6*0Sstevel@tonic-gate * are met: 7*0Sstevel@tonic-gate * 1. Redistributions of source code must retain the above copyright 8*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer. 9*0Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright 10*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the 11*0Sstevel@tonic-gate * documentation and/or other materials provided with the distribution. 12*0Sstevel@tonic-gate * 13*0Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14*0Sstevel@tonic-gate * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15*0Sstevel@tonic-gate * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16*0Sstevel@tonic-gate * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17*0Sstevel@tonic-gate * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18*0Sstevel@tonic-gate * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19*0Sstevel@tonic-gate * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20*0Sstevel@tonic-gate * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21*0Sstevel@tonic-gate * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22*0Sstevel@tonic-gate * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23*0Sstevel@tonic-gate */ 24*0Sstevel@tonic-gate 25*0Sstevel@tonic-gate #include "includes.h" 26*0Sstevel@tonic-gate RCSID("$OpenBSD: readpass.c,v 1.27 2002/03/26 15:58:46 markus Exp $"); 27*0Sstevel@tonic-gate 28*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 29*0Sstevel@tonic-gate 30*0Sstevel@tonic-gate #include "xmalloc.h" 31*0Sstevel@tonic-gate #include "readpass.h" 32*0Sstevel@tonic-gate #include "pathnames.h" 33*0Sstevel@tonic-gate #include "log.h" 34*0Sstevel@tonic-gate #include "ssh.h" 35*0Sstevel@tonic-gate 36*0Sstevel@tonic-gate static char * 37*0Sstevel@tonic-gate ssh_askpass(char *askpass, const char *msg) 38*0Sstevel@tonic-gate { 39*0Sstevel@tonic-gate pid_t pid; 40*0Sstevel@tonic-gate size_t len; 41*0Sstevel@tonic-gate char *pass; 42*0Sstevel@tonic-gate int p[2], status, ret; 43*0Sstevel@tonic-gate char buf[1024]; 44*0Sstevel@tonic-gate 45*0Sstevel@tonic-gate if (fflush(stdout) != 0) 46*0Sstevel@tonic-gate error("ssh_askpass: fflush: %s", strerror(errno)); 47*0Sstevel@tonic-gate if (askpass == NULL) 48*0Sstevel@tonic-gate fatal("internal error: askpass undefined"); 49*0Sstevel@tonic-gate if (pipe(p) < 0) { 50*0Sstevel@tonic-gate error("ssh_askpass: pipe: %s", strerror(errno)); 51*0Sstevel@tonic-gate return xstrdup(""); 52*0Sstevel@tonic-gate } 53*0Sstevel@tonic-gate if ((pid = fork()) < 0) { 54*0Sstevel@tonic-gate error("ssh_askpass: fork: %s", strerror(errno)); 55*0Sstevel@tonic-gate return xstrdup(""); 56*0Sstevel@tonic-gate } 57*0Sstevel@tonic-gate if (pid == 0) { 58*0Sstevel@tonic-gate seteuid(getuid()); 59*0Sstevel@tonic-gate setuid(getuid()); 60*0Sstevel@tonic-gate close(p[0]); 61*0Sstevel@tonic-gate if (dup2(p[1], STDOUT_FILENO) < 0) 62*0Sstevel@tonic-gate fatal("ssh_askpass: dup2: %s", strerror(errno)); 63*0Sstevel@tonic-gate execlp(askpass, askpass, msg, (char *) 0); 64*0Sstevel@tonic-gate fatal("ssh_askpass: exec(%s): %s", askpass, strerror(errno)); 65*0Sstevel@tonic-gate } 66*0Sstevel@tonic-gate close(p[1]); 67*0Sstevel@tonic-gate 68*0Sstevel@tonic-gate len = ret = 0; 69*0Sstevel@tonic-gate do { 70*0Sstevel@tonic-gate ret = read(p[0], buf + len, sizeof(buf) - 1 - len); 71*0Sstevel@tonic-gate if (ret == -1 && errno == EINTR) 72*0Sstevel@tonic-gate continue; 73*0Sstevel@tonic-gate if (ret <= 0) 74*0Sstevel@tonic-gate break; 75*0Sstevel@tonic-gate len += ret; 76*0Sstevel@tonic-gate } while (sizeof(buf) - 1 - len > 0); 77*0Sstevel@tonic-gate buf[len] = '\0'; 78*0Sstevel@tonic-gate 79*0Sstevel@tonic-gate close(p[0]); 80*0Sstevel@tonic-gate while (waitpid(pid, &status, 0) < 0) 81*0Sstevel@tonic-gate if (errno != EINTR) 82*0Sstevel@tonic-gate break; 83*0Sstevel@tonic-gate 84*0Sstevel@tonic-gate buf[strcspn(buf, "\r\n")] = '\0'; 85*0Sstevel@tonic-gate pass = xstrdup(buf); 86*0Sstevel@tonic-gate memset(buf, 0, sizeof(buf)); 87*0Sstevel@tonic-gate return pass; 88*0Sstevel@tonic-gate } 89*0Sstevel@tonic-gate 90*0Sstevel@tonic-gate /* 91*0Sstevel@tonic-gate * Reads a passphrase from /dev/tty with echo turned off/on. Returns the 92*0Sstevel@tonic-gate * passphrase (allocated with xmalloc). Exits if EOF is encountered. If 93*0Sstevel@tonic-gate * RP_ALLOW_STDIN is set, the passphrase will be read from stdin if no 94*0Sstevel@tonic-gate * tty is available 95*0Sstevel@tonic-gate */ 96*0Sstevel@tonic-gate char * 97*0Sstevel@tonic-gate read_passphrase(const char *prompt, int flags) 98*0Sstevel@tonic-gate { 99*0Sstevel@tonic-gate char *askpass = NULL, *ret, buf[1024]; 100*0Sstevel@tonic-gate int rppflags, use_askpass = 0, ttyfd; 101*0Sstevel@tonic-gate 102*0Sstevel@tonic-gate rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF; 103*0Sstevel@tonic-gate if (flags & RP_ALLOW_STDIN) { 104*0Sstevel@tonic-gate if (!isatty(STDIN_FILENO)) 105*0Sstevel@tonic-gate use_askpass = 1; 106*0Sstevel@tonic-gate } else { 107*0Sstevel@tonic-gate rppflags |= RPP_REQUIRE_TTY; 108*0Sstevel@tonic-gate ttyfd = open(_PATH_TTY, O_RDWR); 109*0Sstevel@tonic-gate if (ttyfd >= 0) 110*0Sstevel@tonic-gate close(ttyfd); 111*0Sstevel@tonic-gate else 112*0Sstevel@tonic-gate use_askpass = 1; 113*0Sstevel@tonic-gate } 114*0Sstevel@tonic-gate 115*0Sstevel@tonic-gate if (use_askpass && getenv("DISPLAY")) { 116*0Sstevel@tonic-gate if (getenv(SSH_ASKPASS_ENV)) 117*0Sstevel@tonic-gate askpass = getenv(SSH_ASKPASS_ENV); 118*0Sstevel@tonic-gate else 119*0Sstevel@tonic-gate askpass = _PATH_SSH_ASKPASS_DEFAULT; 120*0Sstevel@tonic-gate return ssh_askpass(askpass, prompt); 121*0Sstevel@tonic-gate } 122*0Sstevel@tonic-gate 123*0Sstevel@tonic-gate if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL) { 124*0Sstevel@tonic-gate if (flags & RP_ALLOW_EOF) 125*0Sstevel@tonic-gate return NULL; 126*0Sstevel@tonic-gate return xstrdup(""); 127*0Sstevel@tonic-gate } 128*0Sstevel@tonic-gate 129*0Sstevel@tonic-gate ret = xstrdup(buf); 130*0Sstevel@tonic-gate memset(buf, 'x', sizeof buf); 131*0Sstevel@tonic-gate return ret; 132*0Sstevel@tonic-gate } 133