1/* vi: ts=8 sts=4 sw=4
2*
3* This file is part of the KDE project, module kdesu.
4* Copyright (C) 2000 Geert Jansen <jansen@kde.org>
5*
6* This is free software; you can use this library under the GNU Library
7* General Public License, version 2. See the file "COPYING.LIB" for the
8* exact licensing terms.
9*
10* ssh.cpp: Execute a program on a remote machine using ssh.
11*/
12
13#include "ssh.h"
14#include "kcookie.h"
15
16#include <config.h>
17
18#include <stdio.h>
19#include <stdlib.h>
20#include <unistd.h>
21#include <fcntl.h>
22#include <signal.h>
23#include <errno.h>
24#include <string.h>
25#include <ctype.h>
26#include <time.h>
27
28#include <sys/types.h>
29#include <sys/stat.h>
30
31#include <QtCore/QBool>
32
33#include <kdebug.h>
34#include <klocale.h>
35#include <kstandarddirs.h>
36
37extern int kdesuDebugArea();
38
39namespace KDESu {
40
41using namespace KDESuPrivate;
42
43class SshProcess::SshProcessPrivate
44{
45public:
46 SshProcessPrivate(const QByteArray &host)
47 : m_Host( host )
48 , m_Stub( "kdesu_stub" )
49 {}
50 QByteArray m_Prompt;
51 QByteArray m_Host;
52 QByteArray m_Error;
53 QByteArray m_Stub;
54};
55
56
57SshProcess::SshProcess(const QByteArray &host, const QByteArray &user, const QByteArray &command)
58 : d( new SshProcessPrivate(host) )
59{
60 m_User = user;
61 m_Command = command;
62 srand(time(0L));
63}
64
65
66SshProcess::~SshProcess()
67{
68 delete d;
69}
70
71void SshProcess::setHost(const QByteArray &host)
72{
73 d->m_Host = host;
74}
75
76
77void SshProcess::setStub(const QByteArray &stub)
78{
79 d->m_Stub = stub;
80}
81
82
83int SshProcess::checkInstall(const char *password)
84{
85 return exec(password, 1);
86}
87
88
89int SshProcess::checkNeedPassword()
90{
91 return exec(0L, 2);
92}
93
94
95int SshProcess::exec(const char *password, int check)
96{
97 if (check)
98 setTerminal(true);
99
100 QList<QByteArray> args;
101 args += "-l"; args += m_User;
102 args += "-o"; args += "StrictHostKeyChecking=no";
103 args += d->m_Host; args += d->m_Stub;
104
105 if (StubProcess::exec("ssh", args) < 0)
106 {
107 return check ? SshNotFound : -1;
108 }
109
110 int ret = ConverseSsh(password, check);
111 if (ret < 0)
112 {
113 if (!check)
114 kError(kdesuDebugArea()) << k_lineinfo << "Conversation with ssh failed.";
115 return ret;
116 }
117 if (check == 2)
118 {
119 if (ret == 1)
120 {
121 kill(m_Pid, SIGTERM);
122 waitForChild();
123 }
124 return ret;
125 }
126
127 if (m_bErase && password)
128 memset(const_cast<char *>(password), 0, qstrlen(password));
129
130 ret = ConverseStub(check);
131 if (ret < 0)
132 {
133 if (!check)
134 kError(kdesuDebugArea()) << k_lineinfo << "Conversation with kdesu_stub failed.";
135 return ret;
136 }
137 else if (ret == 1)
138 {
139 kill(m_Pid, SIGTERM);
140 waitForChild();
141 ret = SshIncorrectPassword;
142 }
143
144 if (check == 1)
145 {
146 waitForChild();
147 return 0;
148 }
149
150 setExitString("Waiting for forwarded connections to terminate");
151 ret = waitForChild();
152 return ret;
153}
154
155QByteArray SshProcess::prompt() const
156{
157 return d->m_Prompt;
158}
159
160QByteArray SshProcess::error() const
161{
162 return d->m_Error;
163}
164
165
166/*
167* Conversation with ssh.
168* If check is 0, this waits for either a "Password: " prompt,
169* or the header of the stub. If a prompt is received, the password is
170* written back. Used for running a command.
171* If check is 1, operation is the same as 0 except that if a stub header is
172* received, the stub is stopped with the "stop" command. This is used for
173* checking a password.
174* If check is 2, operation is the same as 1, except that no password is
175* written. The prompt is saved to m_Prompt. Used for checking the need for
176* a password.
177*/
178
179int SshProcess::ConverseSsh(const char *password, int check)
180{
181 unsigned i, j, colon;
182
183 QByteArray line;
184 int state = 0;
185
186 while (state < 2)
187 {
188 line = readLine();
189 const uint len = line.length();
190 if (line.isNull())
191 return -1;
192
193 switch (state) {
194 case 0:
195 // Check for "kdesu_stub" header.
196 if (line == "kdesu_stub")
197 {
198 unreadLine(line);
199 return 0;
200 }
201
202 // Match "Password: " with the regex ^[^:]+:[\w]*$.
203 for (i=0,j=0,colon=0; i<len; ++i)
204 {
205 if (line[i] == ':')
206 {
207 j = i; colon++;
208 continue;
209 }
210 if (!isspace(line[i]))
211 j++;
212 }
213 if ((colon == 1) && (line[j] == ':'))
214 {
215 if (check == 2)
216 {
217 d->m_Prompt = line;
218 return SshNeedsPassword;
219 }
220 if (WaitSlave())
221 return -1;
222 write(fd(), password, strlen(password));
223 write(fd(), "\n", 1);
224 state++;
225 break;
226 }
227
228 // Warning/error message.
229 d->m_Error += line; d->m_Error += '\n';
230 if (m_bTerminal)
231 fprintf(stderr, "ssh: %s\n", line.constData());
232 break;
233
234 case 1:
235 if (line.isEmpty())
236 {
237 state++;
238 break;
239 }
240 return -1;
241 }
242 }
243 return 0;
244}
245
246
247// Display redirection is handled by ssh natively.
248QByteArray SshProcess::display()
249{
250 return "no";
251}
252
253
254QByteArray SshProcess::displayAuth()
255{
256 return "no";
257}
258
259void SshProcess::virtual_hook( int id, void* data )
260{ StubProcess::virtual_hook( id, data ); }
261
262}
263