2 * Copyright (c) 2001 Markus Friedl. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
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.
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.
26 RCSID("$OpenBSD: readpass.c,v 1.35 2006/02/10 01:44:26 stevesk Exp $");
28 #include <sys/types.h>
37 #include "pathnames.h"
42 ssh_askpass(char *askpass, const char *msg)
47 int p[2], status, ret;
50 if (fflush(stdout) != 0)
51 error("ssh_askpass: fflush: %s", strerror(errno));
53 fatal("internal error: askpass undefined");
55 error("ssh_askpass: pipe: %s", strerror(errno));
58 if ((pid = fork()) < 0) {
59 error("ssh_askpass: fork: %s", strerror(errno));
66 if (dup2(p[1], STDOUT_FILENO) < 0)
67 fatal("ssh_askpass: dup2: %s", strerror(errno));
68 execlp(askpass, askpass, msg, (char *) 0);
69 fatal("ssh_askpass: exec(%s): %s", askpass, strerror(errno));
75 ret = read(p[0], buf + len, sizeof(buf) - 1 - len);
76 if (ret == -1 && errno == EINTR)
81 } while (sizeof(buf) - 1 - len > 0);
85 while (waitpid(pid, &status, 0) < 0)
89 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
90 memset(buf, 0, sizeof(buf));
94 buf[strcspn(buf, "\r\n")] = '\0';
96 memset(buf, 0, sizeof(buf));
101 * Reads a passphrase from /dev/tty with echo turned off/on. Returns the
102 * passphrase (allocated with xmalloc). Exits if EOF is encountered. If
103 * RP_ALLOW_STDIN is set, the passphrase will be read from stdin if no
107 read_passphrase(const char *prompt, int flags)
109 char *askpass = NULL, *ret, buf[1024];
110 int rppflags, use_askpass = 0, ttyfd;
112 rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF;
113 if (flags & RP_USE_ASKPASS)
115 else if (flags & RP_ALLOW_STDIN) {
116 if (!isatty(STDIN_FILENO)) {
117 debug("read_passphrase: stdin is not a tty");
121 rppflags |= RPP_REQUIRE_TTY;
122 ttyfd = open(_PATH_TTY, O_RDWR);
126 debug("read_passphrase: can't open %s: %s", _PATH_TTY,
132 if ((flags & RP_USE_ASKPASS) && getenv("DISPLAY") == NULL)
133 return (flags & RP_ALLOW_EOF) ? NULL : xstrdup("");
135 if (use_askpass && getenv("DISPLAY")) {
136 if (getenv(SSH_ASKPASS_ENV))
137 askpass = getenv(SSH_ASKPASS_ENV);
139 askpass = _PATH_SSH_ASKPASS_DEFAULT;
140 if ((ret = ssh_askpass(askpass, prompt)) == NULL)
141 if (!(flags & RP_ALLOW_EOF))
146 if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL) {
147 if (flags & RP_ALLOW_EOF)
153 memset(buf, 'x', sizeof buf);
158 ask_permission(const char *fmt, ...)
161 char *p, prompt[1024];
165 vsnprintf(prompt, sizeof(prompt), fmt, args);
168 p = read_passphrase(prompt, RP_USE_ASKPASS|RP_ALLOW_EOF);
171 * Accept empty responses and responses consisting
172 * of the word "yes" as affirmative.
174 if (*p == '\0' || *p == '\n' ||
175 strcasecmp(p, "yes") == 0)