Annotation of src/usr.bin/ssh/readpass.c, Revision 1.22.2.2
1.1 deraadt 1: /*
1.22.2.2! jason 2: * Copyright (c) 2001 Markus Friedl. All rights reserved.
1.8 deraadt 3: *
4: * Redistribution and use in source and binary forms, with or without
5: * modification, are permitted provided that the following conditions
6: * are met:
7: * 1. Redistributions of source code must retain the above copyright
8: * notice, this list of conditions and the following disclaimer.
9: * 2. Redistributions in binary form must reproduce the above copyright
10: * notice, this list of conditions and the following disclaimer in the
11: * documentation and/or other materials provided with the distribution.
12: *
1.22.2.2! jason 13: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
! 14: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
! 15: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
! 16: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
! 17: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
! 18: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
! 19: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
! 20: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
! 21: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
! 22: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.6 deraadt 23: */
1.1 deraadt 24:
25: #include "includes.h"
1.22.2.2! jason 26: RCSID("$OpenBSD: readpass.c,v 1.26 2002/02/13 00:39:15 markus Exp $");
1.19 markus 27:
28: #include <readpassphrase.h>
1.1 deraadt 29:
30: #include "xmalloc.h"
1.14 itojun 31: #include "readpass.h"
1.15 markus 32: #include "pathnames.h"
33: #include "log.h"
34: #include "ssh.h"
35:
1.18 itojun 36: static char *
1.16 mouring 37: ssh_askpass(char *askpass, const char *msg)
1.15 markus 38: {
39: pid_t pid;
40: size_t len;
1.22.2.1 jason 41: char *pass;
1.22.2.2! jason 42: int p[2], status, ret;
1.15 markus 43: char buf[1024];
44:
45: if (fflush(stdout) != 0)
46: error("ssh_askpass: fflush: %s", strerror(errno));
47: if (askpass == NULL)
48: fatal("internal error: askpass undefined");
1.21 markus 49: if (pipe(p) < 0) {
50: error("ssh_askpass: pipe: %s", strerror(errno));
51: return xstrdup("");
52: }
53: if ((pid = fork()) < 0) {
54: error("ssh_askpass: fork: %s", strerror(errno));
55: return xstrdup("");
56: }
1.15 markus 57: if (pid == 0) {
58: seteuid(getuid());
59: setuid(getuid());
60: close(p[0]);
61: if (dup2(p[1], STDOUT_FILENO) < 0)
62: fatal("ssh_askpass: dup2: %s", strerror(errno));
63: execlp(askpass, askpass, msg, (char *) 0);
64: fatal("ssh_askpass: exec(%s): %s", askpass, strerror(errno));
65: }
66: close(p[1]);
1.22.2.2! jason 67:
! 68: len = ret = 0;
! 69: do {
! 70: ret = read(p[0], buf + len, sizeof(buf) - 1 - len);
! 71: if (ret == -1 && errno == EINTR)
! 72: continue;
! 73: if (ret <= 0)
! 74: break;
! 75: len += ret;
! 76: } while (sizeof(buf) - 1 - len > 0);
! 77: buf[len] = '\0';
! 78:
1.15 markus 79: close(p[0]);
80: while (waitpid(pid, &status, 0) < 0)
81: if (errno != EINTR)
82: break;
1.22.2.2! jason 83:
1.22.2.1 jason 84: buf[strcspn(buf, "\r\n")] = '\0';
1.15 markus 85: pass = xstrdup(buf);
86: memset(buf, 0, sizeof(buf));
87: return pass;
88: }
89:
1.7 markus 90: /*
1.19 markus 91: * Reads a passphrase from /dev/tty with echo turned off/on. Returns the
92: * passphrase (allocated with xmalloc). Exits if EOF is encountered. If
93: * RP_ALLOW_STDIN is set, the passphrase will be read from stdin if no
94: * tty is available
1.12 markus 95: */
1.5 markus 96: char *
1.19 markus 97: read_passphrase(const char *prompt, int flags)
1.1 deraadt 98: {
1.19 markus 99: char *askpass = NULL, *ret, buf[1024];
100: int rppflags, use_askpass = 0, ttyfd;
1.15 markus 101:
1.19 markus 102: rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF;
103: if (flags & RP_ALLOW_STDIN) {
1.15 markus 104: if (!isatty(STDIN_FILENO))
105: use_askpass = 1;
106: } else {
1.19 markus 107: rppflags |= RPP_REQUIRE_TTY;
1.22.2.2! jason 108: ttyfd = open(_PATH_TTY, O_RDWR);
1.15 markus 109: if (ttyfd >= 0)
110: close(ttyfd);
111: else
112: use_askpass = 1;
113: }
114:
115: if (use_askpass && getenv("DISPLAY")) {
116: if (getenv(SSH_ASKPASS_ENV))
117: askpass = getenv(SSH_ASKPASS_ENV);
118: else
119: askpass = _PATH_SSH_ASKPASS_DEFAULT;
120: return ssh_askpass(askpass, prompt);
121: }
122:
1.19 markus 123: if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL)
1.20 markus 124: return xstrdup("");
1.19 markus 125:
126: ret = xstrdup(buf);
127: memset(buf, 'x', sizeof buf);
128: return ret;
1.1 deraadt 129: }