1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
/*
* Dropbear SSH
*
* Copyright (c) 2002,2003 Matt Johnston
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE. */
#include "includes.h"
#include "buffer.h"
#include "dbutil.h"
#include "session.h"
#include "ssh.h"
#include "runopts.h"
#ifdef ENABLE_CLI_PASSWORD_AUTH
#ifdef ENABLE_CLI_ASKPASS_HELPER
/* Returns 1 if we want to use the askpass program, 0 otherwise */
static int want_askpass()
{
char* askpass_prog = NULL;
askpass_prog = getenv("SSH_ASKPASS");
return askpass_prog && !isatty(STDIN_FILENO) && getenv("DISPLAY");
}
/* returns a statically allocated password from a helper app, or NULL
* on failure */
static char *gui_getpass(const char *prompt) {
pid_t pid;
int p[2], maxlen, len, status;
static char buf[DROPBEAR_MAX_CLI_PASS + 1];
char* helper = NULL;
TRACE(("enter gui_getpass"))
helper = getenv("SSH_ASKPASS");
if (!helper)
{
TRACE(("leave gui_getpass: no askpass program"))
return NULL;
}
if (pipe(p) < 0) {
TRACE(("error creating child pipe"))
return NULL;
}
pid = fork();
if (pid < 0) {
TRACE(("fork error"))
return NULL;
}
if (!pid) {
/* child */
close(p[0]);
if (dup2(p[1], STDOUT_FILENO) < 0) {
TRACE(("error redirecting stdout"))
exit(1);
}
close(p[1]);
execlp(helper, helper, prompt, (char *)0);
TRACE(("execlp error"))
exit(1);
}
close(p[1]);
maxlen = sizeof(buf);
while (maxlen > 0) {
len = read(p[0], buf + sizeof(buf) - maxlen, maxlen);
if (len > 0) {
maxlen -= len;
} else {
if (errno != EINTR)
break;
}
}
close(p[0]);
while (waitpid(pid, &status, 0) < 0 && errno == EINTR)
;
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
return(NULL);
len = sizeof(buf) - maxlen;
buf[len] = '\0';
if (len > 0 && buf[len - 1] == '\n')
buf[len - 1] = '\0';
TRACE(("leave gui_getpass"))
return(buf);
}
#endif /* ENABLE_CLI_ASKPASS_HELPER */
int cli_auth_password() {
char* password = NULL;
TRACE(("enter cli_auth_password"))
CHECKCLEARTOWRITE();
#ifdef ENABLE_CLI_ASKPASS_HELPER
if (want_askpass())
password = gui_getpass("Password: ");
else
#endif
password = getpass("Password: ");
if (password == NULL)
return 0;
buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_REQUEST);
buf_putstring(ses.writepayload, cli_opts.username,
strlen(cli_opts.username));
buf_putstring(ses.writepayload, SSH_SERVICE_CONNECTION,
SSH_SERVICE_CONNECTION_LEN);
buf_putstring(ses.writepayload, AUTH_METHOD_PASSWORD,
AUTH_METHOD_PASSWORD_LEN);
buf_putbyte(ses.writepayload, 0); /* FALSE - so says the spec */
buf_putstring(ses.writepayload, password, strlen(password));
encrypt_packet();
m_burn(password, strlen(password));
TRACE(("leave cli_auth_password"))
return 1; /* Password auth can always be tried */
}
#endif /* ENABLE_CLI_PASSWORD_AUTH */
|
