]>
Commit | Line | Data |
---|---|---|
3c0ef626 | 1 | /* |
e9a17296 | 2 | * Copyright (c) 2001 Markus Friedl. All rights reserved. |
3c0ef626 | 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. | |
3c0ef626 | 12 | * |
e9a17296 | 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. | |
3c0ef626 | 23 | */ |
24 | ||
25 | #include "includes.h" | |
665a873d | 26 | RCSID("$OpenBSD: readpass.c,v 1.33 2005/05/02 21:13:22 markus Exp $"); |
3c0ef626 | 27 | |
28 | #include "xmalloc.h" | |
c9f39d2c | 29 | #include "misc.h" |
3c0ef626 | 30 | #include "pathnames.h" |
31 | #include "log.h" | |
32 | #include "ssh.h" | |
33 | ||
34 | static char * | |
35 | ssh_askpass(char *askpass, const char *msg) | |
36 | { | |
37 | pid_t pid; | |
38 | size_t len; | |
39 | char *pass; | |
e9a17296 | 40 | int p[2], status, ret; |
3c0ef626 | 41 | char buf[1024]; |
42 | ||
43 | if (fflush(stdout) != 0) | |
44 | error("ssh_askpass: fflush: %s", strerror(errno)); | |
45 | if (askpass == NULL) | |
46 | fatal("internal error: askpass undefined"); | |
47 | if (pipe(p) < 0) { | |
48 | error("ssh_askpass: pipe: %s", strerror(errno)); | |
6a9b3198 | 49 | return NULL; |
3c0ef626 | 50 | } |
51 | if ((pid = fork()) < 0) { | |
52 | error("ssh_askpass: fork: %s", strerror(errno)); | |
6a9b3198 | 53 | return NULL; |
3c0ef626 | 54 | } |
55 | if (pid == 0) { | |
56 | seteuid(getuid()); | |
57 | setuid(getuid()); | |
58 | close(p[0]); | |
59 | if (dup2(p[1], STDOUT_FILENO) < 0) | |
60 | fatal("ssh_askpass: dup2: %s", strerror(errno)); | |
61 | execlp(askpass, askpass, msg, (char *) 0); | |
62 | fatal("ssh_askpass: exec(%s): %s", askpass, strerror(errno)); | |
63 | } | |
64 | close(p[1]); | |
e9a17296 | 65 | |
66 | len = ret = 0; | |
67 | do { | |
68 | ret = read(p[0], buf + len, sizeof(buf) - 1 - len); | |
69 | if (ret == -1 && errno == EINTR) | |
70 | continue; | |
71 | if (ret <= 0) | |
72 | break; | |
73 | len += ret; | |
74 | } while (sizeof(buf) - 1 - len > 0); | |
75 | buf[len] = '\0'; | |
76 | ||
3c0ef626 | 77 | close(p[0]); |
78 | while (waitpid(pid, &status, 0) < 0) | |
79 | if (errno != EINTR) | |
80 | break; | |
e9a17296 | 81 | |
6a9b3198 | 82 | if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { |
83 | memset(buf, 0, sizeof(buf)); | |
84 | return NULL; | |
85 | } | |
86 | ||
3c0ef626 | 87 | buf[strcspn(buf, "\r\n")] = '\0'; |
88 | pass = xstrdup(buf); | |
89 | memset(buf, 0, sizeof(buf)); | |
90 | return pass; | |
91 | } | |
92 | ||
93 | /* | |
94 | * Reads a passphrase from /dev/tty with echo turned off/on. Returns the | |
95 | * passphrase (allocated with xmalloc). Exits if EOF is encountered. If | |
96 | * RP_ALLOW_STDIN is set, the passphrase will be read from stdin if no | |
97 | * tty is available | |
98 | */ | |
99 | char * | |
100 | read_passphrase(const char *prompt, int flags) | |
101 | { | |
102 | char *askpass = NULL, *ret, buf[1024]; | |
103 | int rppflags, use_askpass = 0, ttyfd; | |
104 | ||
105 | rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF; | |
c9f39d2c | 106 | if (flags & RP_USE_ASKPASS) |
107 | use_askpass = 1; | |
108 | else if (flags & RP_ALLOW_STDIN) { | |
665a873d | 109 | if (!isatty(STDIN_FILENO)) { |
110 | debug("read_passphrase: stdin is not a tty"); | |
3c0ef626 | 111 | use_askpass = 1; |
665a873d | 112 | } |
3c0ef626 | 113 | } else { |
114 | rppflags |= RPP_REQUIRE_TTY; | |
e9a17296 | 115 | ttyfd = open(_PATH_TTY, O_RDWR); |
3c0ef626 | 116 | if (ttyfd >= 0) |
117 | close(ttyfd); | |
665a873d | 118 | else { |
119 | debug("read_passphrase: can't open %s: %s", _PATH_TTY, | |
120 | strerror(errno)); | |
3c0ef626 | 121 | use_askpass = 1; |
665a873d | 122 | } |
3c0ef626 | 123 | } |
124 | ||
c9f39d2c | 125 | if ((flags & RP_USE_ASKPASS) && getenv("DISPLAY") == NULL) |
126 | return (flags & RP_ALLOW_EOF) ? NULL : xstrdup(""); | |
127 | ||
3c0ef626 | 128 | if (use_askpass && getenv("DISPLAY")) { |
129 | if (getenv(SSH_ASKPASS_ENV)) | |
130 | askpass = getenv(SSH_ASKPASS_ENV); | |
131 | else | |
132 | askpass = _PATH_SSH_ASKPASS_DEFAULT; | |
6a9b3198 | 133 | if ((ret = ssh_askpass(askpass, prompt)) == NULL) |
134 | if (!(flags & RP_ALLOW_EOF)) | |
135 | return xstrdup(""); | |
136 | return ret; | |
3c0ef626 | 137 | } |
138 | ||
700318f3 | 139 | if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL) { |
140 | if (flags & RP_ALLOW_EOF) | |
141 | return NULL; | |
3c0ef626 | 142 | return xstrdup(""); |
700318f3 | 143 | } |
3c0ef626 | 144 | |
145 | ret = xstrdup(buf); | |
146 | memset(buf, 'x', sizeof buf); | |
147 | return ret; | |
148 | } | |
996d5e62 | 149 | |
150 | int | |
151 | ask_permission(const char *fmt, ...) | |
152 | { | |
153 | va_list args; | |
154 | char *p, prompt[1024]; | |
155 | int allowed = 0; | |
156 | ||
157 | va_start(args, fmt); | |
158 | vsnprintf(prompt, sizeof(prompt), fmt, args); | |
159 | va_end(args); | |
160 | ||
161 | p = read_passphrase(prompt, RP_USE_ASKPASS|RP_ALLOW_EOF); | |
162 | if (p != NULL) { | |
163 | /* | |
164 | * Accept empty responses and responses consisting | |
165 | * of the word "yes" as affirmative. | |
166 | */ | |
167 | if (*p == '\0' || *p == '\n' || | |
168 | strcasecmp(p, "yes") == 0) | |
169 | allowed = 1; | |
170 | xfree(p); | |
171 | } | |
172 | ||
173 | return (allowed); | |
174 | } |