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1 | \define{versionidfaq} \versionid $Id$ |
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2 | |
421406a4 |
3 | \A{faq} PuTTY \i{FAQ} |
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4 | |
5 | This FAQ is published on the PuTTY web site, and also provided as an |
6 | appendix in the manual. |
7 | |
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8 | \H{faq-intro} Introduction |
9 | |
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10 | \S{faq-what}{Question} What is PuTTY? |
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11 | |
12 | PuTTY is a client program for the SSH, Telnet and Rlogin network |
13 | protocols. |
14 | |
15 | These protocols are all used to run a remote session on a computer, |
16 | over a network. PuTTY implements the client end of that session: the |
17 | end at which the session is displayed, rather than the end at which |
18 | it runs. |
19 | |
20 | In really simple terms: you run PuTTY on a Windows machine, and tell |
21 | it to connect to (for example) a Unix machine. PuTTY opens a window. |
22 | Then, anything you type into that window is sent straight to the |
23 | Unix machine, and everything the Unix machine sends back is |
24 | displayed in the window. So you can work on the Unix machine as if |
25 | you were sitting at its console, while actually sitting somewhere |
26 | else. |
27 | |
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28 | \H{faq-support} Features supported in PuTTY |
29 | |
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30 | \I{supported features}In general, if you want to know if PuTTY supports |
31 | a particular feature, you should look for it on the |
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32 | \W{http://www.chiark.greenend.org.uk/~sgtatham/putty/}{PuTTY web site}. |
33 | In particular: |
34 | |
35 | \b try the |
36 | \W{http://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html}{changes |
37 | page}, and see if you can find the feature on there. If a feature is |
38 | listed there, it's been implemented. If it's listed as a change made |
39 | \e{since} the latest version, it should be available in the |
40 | development snapshots, in which case testing will be very welcome. |
41 | |
42 | \b try the |
ebe9a956 |
43 | \W{http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/}{Wishlist |
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44 | page}, and see if you can find the feature there. If it's on there, |
b21091fb |
45 | and not in the \q{Recently fixed} section, it probably \e{hasn't} been |
46 | implemented. |
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47 | |
2e85c969 |
48 | \S{faq-ssh2}{Question} Does PuTTY support SSH-2? |
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49 | |
2e85c969 |
50 | Yes. SSH-2 support has been available in PuTTY since version 0.50. |
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51 | |
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52 | Public key authentication (both RSA and DSA) in SSH-2 is new in |
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53 | version 0.52. |
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54 | |
a1d2976b |
55 | \S{faq-ssh2-keyfmt}{Question} Does PuTTY support reading OpenSSH or |
2e85c969 |
56 | \cw{ssh.com} SSH-2 private key files? |
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57 | |
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58 | PuTTY doesn't support this natively, but as of 0.53 |
59 | PuTTYgen can convert both OpenSSH and \cw{ssh.com} private key |
60 | files into PuTTY's format. |
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61 | |
2e85c969 |
62 | \S{faq-ssh1}{Question} Does PuTTY support SSH-1? |
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63 | |
2e85c969 |
64 | Yes. SSH-1 support has always been available in PuTTY. |
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65 | |
421406a4 |
66 | \S{faq-localecho}{Question} Does PuTTY support \i{local echo}? |
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67 | |
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68 | Yes. Version 0.52 has proper support for local echo. |
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69 | |
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70 | In version 0.51 and before, local echo could not be separated from |
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71 | local line editing (where you type a line of text locally, and it is |
72 | not sent to the server until you press Return, so you have the |
73 | chance to edit it and correct mistakes \e{before} the server sees |
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74 | it). New in version 0.52, local echo and local line editing are |
75 | separate options, and by default PuTTY will try to determine |
76 | automatically whether to enable them or not, based on which protocol |
77 | you have selected and also based on hints from the server. If you |
78 | have a problem with PuTTY's default choice, you can force each |
79 | option to be enabled or disabled as you choose. The controls are in |
80 | the Terminal panel, in the section marked \q{Line discipline |
81 | options}. |
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82 | |
270bd741 |
83 | \S{faq-savedsettings}{Question} Does PuTTY support storing settings, |
84 | so I don't have to change them every time? |
85 | |
86 | Yes, all of PuTTY's settings can be saved in named session profiles. |
00c1d39a |
87 | You can also change the default settings that are used for new sessions. |
270bd741 |
88 | See \k{config-saving} in the documentation for how to do this. |
89 | |
a1d2976b |
90 | \S{faq-disksettings}{Question} Does PuTTY support storing its |
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91 | settings in a disk file? |
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92 | |
93 | Not at present, although \k{config-file} in the documentation gives |
94 | a method of achieving the same effect. |
95 | |
a1d2976b |
96 | \S{faq-fullscreen}{Question} Does PuTTY support full-screen mode, |
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97 | like a DOS box? |
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98 | |
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99 | Yes; this is a new feature in version 0.52. |
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100 | |
babac7bd |
101 | \S{faq-password-remember}{Question} Does PuTTY have the ability to |
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102 | \i{remember my password} so I don't have to type it every time? |
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103 | |
104 | No, it doesn't. |
105 | |
106 | Remembering your password is a bad plan for obvious security |
107 | reasons: anyone who gains access to your machine while you're away |
108 | from your desk can find out the remembered password, and use it, |
109 | abuse it or change it. |
110 | |
111 | In addition, it's not even \e{possible} for PuTTY to automatically |
112 | send your password in a Telnet session, because Telnet doesn't give |
113 | the client software any indication of which part of the login |
114 | process is the password prompt. PuTTY would have to guess, by |
115 | looking for words like \q{password} in the session data; and if your |
116 | login program is written in something other than English, this won't |
117 | work. |
118 | |
119 | In SSH, remembering your password would be possible in theory, but |
120 | there doesn't seem to be much point since SSH supports public key |
121 | authentication, which is more flexible and more secure. See |
122 | \k{pubkey} in the documentation for a full discussion of public key |
123 | authentication. |
124 | |
a1d2976b |
125 | \S{faq-hostkeys}{Question} Is there an option to turn off the |
421406a4 |
126 | \I{verifying the host key}annoying host key prompts? |
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127 | |
128 | No, there isn't. And there won't be. Even if you write it yourself |
129 | and send us the patch, we won't accept it. |
130 | |
131 | Those annoying host key prompts are the \e{whole point} of SSH. |
132 | Without them, all the cryptographic technology SSH uses to secure |
133 | your session is doing nothing more than making an attacker's job |
134 | slightly harder; instead of sitting between you and the server with |
135 | a packet sniffer, the attacker must actually subvert a router and |
136 | start modifying the packets going back and forth. But that's not all |
137 | that much harder than just sniffing; and without host key checking, |
138 | it will go completely undetected by client or server. |
139 | |
140 | Host key checking is your guarantee that the encryption you put on |
141 | your data at the client end is the \e{same} encryption taken off the |
142 | data at the server end; it's your guarantee that it hasn't been |
143 | removed and replaced somewhere on the way. Host key checking makes |
144 | the attacker's job \e{astronomically} hard, compared to packet |
145 | sniffing, and even compared to subverting a router. Instead of |
146 | applying a little intelligence and keeping an eye on Bugtraq, the |
147 | attacker must now perform a brute-force attack against at least one |
148 | military-strength cipher. That insignificant host key prompt really |
149 | does make \e{that} much difference. |
150 | |
151 | If you're having a specific problem with host key checking - perhaps |
152 | you want an automated batch job to make use of PSCP or Plink, and |
153 | the interactive host key prompt is hanging the batch process - then |
154 | the right way to fix it is to add the correct host key to the |
155 | Registry in advance. That way, you retain the \e{important} feature |
156 | of host key checking: the right key will be accepted and the wrong |
157 | ones will not. Adding an option to turn host key checking off |
158 | completely is the wrong solution and we will not do it. |
159 | |
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160 | If you have host keys available in the common \i\c{known_hosts} format, |
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161 | we have a script called |
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162 | \W{http://www.tartarus.org/~simon-anonsvn/viewcvs.cgi/putty/contrib/kh2reg.py?view=markup}\c{kh2reg.py} |
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163 | to convert them to a Windows .REG file, which can be installed ahead of |
164 | time by double-clicking or using \c{REGEDIT}. |
165 | |
a1d2976b |
166 | \S{faq-server}{Question} Will you write an SSH server for the PuTTY |
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167 | suite, to go with the client? |
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168 | |
169 | No. The only reason we might want to would be if we could easily |
170 | re-use existing code and significantly cut down the effort. We don't |
171 | believe this is the case; there just isn't enough common ground |
172 | between an SSH client and server to make it worthwhile. |
173 | |
174 | If someone else wants to use bits of PuTTY in the process of writing |
175 | a Windows SSH server, they'd be perfectly welcome to of course, but |
176 | I really can't see it being a lot less effort for us to do that than |
177 | it would be for us to write a server from the ground up. We don't |
178 | have time, and we don't have motivation. The code is available if |
179 | anyone else wants to try it. |
180 | |
67325335 |
181 | \S{faq-pscp-ascii}{Question} Can PSCP or PSFTP transfer files in |
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182 | \i{ASCII} mode? |
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183 | |
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184 | Unfortunately not. |
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185 | |
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186 | Until recently, this was a limitation of the file transfer protocols: |
187 | the SCP and SFTP protocols had no notion of transferring a file in |
188 | anything other than binary mode. (This is still true of SCP.) |
189 | |
190 | The current draft protocol spec of SFTP proposes a means of |
191 | implementing ASCII transfer. At some point PSCP/PSFTP may implement |
192 | this proposal. |
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193 | |
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194 | \H{faq-ports} Ports to other operating systems |
195 | |
196 | The eventual goal is for PuTTY to be a multi-platform program, able |
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197 | to run on at least Windows, Mac OS and Unix. |
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198 | |
199 | Porting will become easier once PuTTY has a generalised porting |
200 | layer, drawing a clear line between platform-dependent and |
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201 | platform-independent code. The general intention was for this |
202 | porting layer to evolve naturally as part of the process of doing |
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203 | the first port; a Unix port has now been released and the plan |
204 | seems to be working so far. |
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205 | |
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206 | \S{faq-ports-general}{Question} What ports of PuTTY exist? |
207 | |
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208 | Currently, release versions of PuTTY tools only run on full Win32 |
209 | systems and Unix. \q{Win32} includes Windows 95, 98, and ME, and it |
210 | includes Windows NT, Windows 2000 and Windows XP. |
211 | |
212 | In the development code, a partial port to the Mac OS (see |
213 | \k{faq-mac-port}) is under way. |
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214 | |
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215 | Currently PuTTY does \e{not} run on Windows CE (see \k{faq-wince}), |
216 | and it does not quite run on the Win32s environment under Windows |
217 | 3.1 (see \k{faq-win31}). |
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218 | |
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219 | We do not have release-quality ports for any other systems at the |
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220 | present time. If anyone told you we had an EPOC port, or an iPaq port, |
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221 | or any other port of PuTTY, they were mistaken. We don't. |
222 | |
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223 | There are some third-party ports to various platforms, mentioned |
224 | on the Links page of our website. |
225 | |
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226 | \S{faq-unix}{Question} \I{Unix version}Is there a port to Unix? |
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227 | |
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228 | As of 0.54, there are Unix ports of most of the traditional PuTTY |
229 | tools, and also one entirely new application. |
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230 | |
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231 | If you look at the source release, you should find a \c{unix} |
232 | subdirectory containing \c{Makefile.gtk}, which should build you Unix |
233 | ports of Plink, PuTTY itself, PuTTYgen, PSCP, PSFTP, and also |
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234 | \i\c{pterm} - an \cw{xterm}-type program which supports the same |
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235 | terminal emulation as PuTTY. We do not yet have a Unix port of |
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236 | Pageant. |
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237 | |
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238 | If you don't have \i{Gtk}, you should still be able to build the |
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239 | command-line tools. |
240 | |
241 | Note that Unix PuTTY has mostly only been tested on Linux so far; |
242 | portability problems such as BSD-style ptys or different header file |
243 | requirements are expected. |
244 | |
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245 | \S{faq-unix-why}{Question} What's the point of the Unix port? Unix |
246 | has OpenSSH. |
247 | |
248 | All sorts of little things. \c{pterm} is directly useful to anyone |
249 | who prefers PuTTY's terminal emulation to \c{xterm}'s, which at |
250 | least some people do. Unix Plink has apparently found a niche among |
251 | people who find the complexity of OpenSSL makes OpenSSH hard to |
252 | install (and who don't mind Plink not having as many features). Some |
253 | users want to generate a large number of SSH keys on Unix and then |
254 | copy them all into PuTTY, and the Unix PuTTYgen should allow them to |
255 | automate that conversion process. |
256 | |
257 | There were development advantages as well; porting PuTTY to Unix was |
258 | a valuable path-finding effort for other future ports, and also |
259 | allowed us to use the excellent Linux tool |
260 | \W{http://valgrind.kde.org/}{Valgrind} to help with debugging, which |
261 | has already improved PuTTY's stability on \e{all} platforms. |
262 | |
263 | However, if you're a Unix user and you can see no reason to switch |
264 | from OpenSSH to PuTTY/Plink, then you're probably right. We don't |
265 | expect our Unix port to be the right thing for everybody. |
266 | |
70cd2027 |
267 | \S{faq-wince}{Question} Will there be a port to Windows CE or PocketPC? |
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268 | |
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269 | It's currently being worked on, but it's only in its early stages yet, |
270 | and certainly isn't yet useful. PuTTY on portable devices would |
271 | clearly be a useful thing, so in the long term I hope it can be |
272 | brought up to release quality. |
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273 | |
b273515b |
274 | There's also a third-party port at |
c2658847 |
275 | \W{http://pocketputty.duxy.net/}\c{http://pocketputty.duxy.net/}. |
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276 | |
421406a4 |
277 | \S{faq-win31}{Question} Is there a port to \i{Windows 3.1}? |
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278 | |
279 | PuTTY is a 32-bit application from the ground up, so it won't run on |
280 | Windows 3.1 as a native 16-bit program; and it would be \e{very} |
281 | hard to port it to do so, because of Windows 3.1's vile memory |
282 | allocation mechanisms. |
283 | |
284 | However, it is possible in theory to compile the existing PuTTY |
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285 | source in such a way that it will run under \i{Win32s} (an extension to |
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286 | Windows 3.1 to let you run 32-bit programs). In order to do this |
287 | you'll need the right kind of C compiler - modern versions of Visual |
288 | C at least have stopped being backwards compatible to Win32s. Also, |
289 | the last time we tried this it didn't work very well. |
290 | |
291 | If you're interested in running PuTTY under Windows 3.1, help and |
292 | testing in this area would be very welcome! |
293 | |
421406a4 |
294 | \S{faq-mac-port}{Question} Will there be a port to the \I{Mac OS}Mac? |
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295 | |
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296 | There are several answers to this question: |
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297 | |
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298 | \b The Unix/Gtk port is already fully working under Mac OS X as an X11 |
299 | application. |
300 | |
99a2d7d4 |
301 | \b A native (Cocoa) Mac OS X port has been started. It's just about |
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302 | usable, but is of nowhere near release quality yet, and is likely to |
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303 | behave in unexpected ways. Currently it's unlikely to be completed |
304 | unless someone steps in to help. |
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305 | |
306 | \b A separate port to the classic Mac OS (pre-OSX) is also in |
307 | progress; it too is not ready yet. |
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308 | |
a1d2976b |
309 | \S{faq-epoc}{Question} Will there be a port to EPOC? |
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310 | |
311 | I hope so, but given that ports aren't really progressing very fast |
312 | even on systems the developers \e{do} already know how to program |
313 | for, it might be a long time before any of us get round to learning |
314 | a new system and doing the port for that. |
315 | |
4f2fd423 |
316 | However, some of the work has been done by other people, and a beta |
317 | port of PuTTY for the Nokia 9200 Communicator series is available |
dc08d858 |
318 | from \W{http://s2putty.sourceforge.net/}\cw{http://s2putty.sourceforge.net/} |
4f2fd423 |
319 | |
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320 | \H{faq-embedding} Embedding PuTTY in other programs |
321 | |
a1d2976b |
322 | \S{faq-dll}{Question} Is the SSH or Telnet code available as a DLL? |
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323 | |
324 | No, it isn't. It would take a reasonable amount of rewriting for |
325 | this to be possible, and since the PuTTY project itself doesn't |
326 | believe in DLLs (they make installation more error-prone) none of us |
327 | has taken the time to do it. |
328 | |
329 | Most of the code cleanup work would be a good thing to happen in |
330 | general, so if anyone feels like helping, we wouldn't say no. |
331 | |
a1d2976b |
332 | \S{faq-vb}{Question} Is the SSH or Telnet code available as a Visual |
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333 | Basic component? |
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334 | |
335 | No, it isn't. None of the PuTTY team uses Visual Basic, and none of |
336 | us has any particular need to make SSH connections from a Visual |
337 | Basic application. In addition, all the preliminary work to turn it |
338 | into a DLL would be necessary first; and furthermore, we don't even |
339 | know how to write VB components. |
340 | |
341 | If someone offers to do some of this work for us, we might consider |
342 | it, but unless that happens I can't see VB integration being |
343 | anywhere other than the very bottom of our priority list. |
344 | |
a1d2976b |
345 | \S{faq-ipc}{Question} How can I use PuTTY to make an SSH connection |
70706890 |
346 | from within another program? |
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347 | |
348 | Probably your best bet is to use Plink, the command-line connection |
349 | tool. If you can start Plink as a second Windows process, and |
350 | arrange for your primary process to be able to send data to the |
351 | Plink process, and receive data from it, through pipes, then you |
352 | should be able to make SSH connections from your program. |
353 | |
354 | This is what CVS for Windows does, for example. |
355 | |
356 | \H{faq-details} Details of PuTTY's operation |
357 | |
421406a4 |
358 | \S{faq-term}{Question} What \i{terminal type} does PuTTY use? |
ee46ef84 |
359 | |
360 | For most purposes, PuTTY can be considered to be an \cw{xterm} |
32c37ecd |
361 | terminal. |
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362 | |
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363 | PuTTY also supports some terminal \i{control sequences} not supported by |
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364 | the real \cw{xterm}: notably the Linux console sequences that |
365 | reconfigure the colour palette, and the title bar control sequences |
421406a4 |
366 | used by \i\cw{DECterm} (which are different from the \cw{xterm} ones; |
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367 | PuTTY supports both). |
368 | |
369 | By default, PuTTY announces its terminal type to the server as |
370 | \c{xterm}. If you have a problem with this, you can reconfigure it |
371 | to say something else; \c{vt220} might help if you have trouble. |
372 | |
a1d2976b |
373 | \S{faq-settings}{Question} Where does PuTTY store its data? |
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374 | |
4c53784e |
375 | On Windows, PuTTY stores most of its data (saved sessions, SSH host |
421406a4 |
376 | keys) in the \i{Registry}. The precise location is |
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377 | |
378 | \c HKEY_CURRENT_USER\Software\SimonTatham\PuTTY |
379 | |
380 | and within that area, saved sessions are stored under \c{Sessions} |
381 | while host keys are stored under \c{SshHostKeys}. |
382 | |
383 | PuTTY also requires a random number seed file, to improve the |
384 | unpredictability of randomly chosen data needed as part of the SSH |
c8f5c5c8 |
385 | cryptography. This is stored by default in a file called \i\c{PUTTY.RND} |
386 | in your Windows home directory (\c{%HOMEDRIVE%\\%HOMEPATH%}), or in |
387 | the actual Windows directory (such as \c{C:\\WINDOWS}) if the home |
388 | directory doesn't exist, for example if you're using Win95. If you |
389 | want to change the location of the random number seed file, you can |
390 | put your chosen pathname in the Registry, at |
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391 | |
392 | \c HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\RandSeedFile |
393 | |
4c53784e |
394 | On Unix, PuTTY stores all of this data in a directory \cw{~/.putty}. |
395 | |
ee46ef84 |
396 | \H{faq-howto} HOWTO questions |
397 | |
aecc2016 |
398 | \S{faq-login}{Question} What login name / password should I use? |
399 | |
400 | This is not a question you should be asking \e{us}. |
401 | |
402 | PuTTY is a communications tool, for making connections to other |
403 | computers. We maintain the tool; we \e{don't} administer any computers |
404 | that you're likely to be able to use, in the same way that the people |
405 | who make web browsers aren't responsible for most of the content you can |
406 | view in them. \#{FIXME: less technical analogy?} We cannot help with |
407 | questions of this sort. |
408 | |
409 | If you know the name of the computer you want to connect to, but don't |
410 | know what login name or password to use, you should talk to whoever |
411 | administers that computer. If you don't know who that is, see the next |
412 | question for some possible ways to find out. |
413 | |
414 | \# FIXME: some people ask us to provide them with a login name |
415 | apparently as random members of the public rather than in the |
416 | belief that we run a server belonging to an organisation they already |
417 | have some relationship with. Not sure what to say to such people. |
418 | |
421406a4 |
419 | \S{faq-commands}{Question} \I{commands on the server}What commands |
420 | can I type into my PuTTY terminal window? |
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421 | |
aecc2016 |
422 | Again, this is not a question you should be asking \e{us}. You need |
423 | to read the manuals, or ask the administrator, of \e{the computer |
424 | you have connected to}. |
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425 | |
426 | PuTTY does not process the commands you type into it. It's only a |
427 | communications tool. It makes a connection to another computer; it |
428 | passes the commands you type to that other computer; and it passes |
429 | the other computer's responses back to you. Therefore, the precise |
430 | range of commands you can use will not depend on PuTTY, but on what |
431 | kind of computer you have connected to and what software is running |
432 | on it. The PuTTY team cannot help you with that. |
433 | |
434 | (Think of PuTTY as being a bit like a telephone. If you phone |
435 | somebody up and you don't know what language to speak to make them |
436 | understand you, it isn't \e{the telephone company}'s job to find |
437 | that out for you. We just provide the means for you to get in touch; |
438 | making yourself understood is somebody else's problem.) |
439 | |
440 | If you are unsure of where to start looking for the administrator of |
441 | your server, a good place to start might be to remember how you |
442 | found out the host name in the PuTTY configuration. If you were |
443 | given that host name by e-mail, for example, you could try asking |
444 | the person who sent you that e-mail. If your company's IT department |
445 | provided you with ready-made PuTTY saved sessions, then that IT |
446 | department can probably also tell you something about what commands |
447 | you can type during those sessions. But the PuTTY maintainer team |
448 | does not administer any server you are likely to be connecting to, |
449 | and cannot help you with questions of this type. |
450 | |
421406a4 |
451 | \S{faq-startmax}{Question} How can I make PuTTY start up \i{maximise}d? |
ee46ef84 |
452 | |
453 | Create a Windows shortcut to start PuTTY from, and set it as \q{Run |
454 | Maximized}. |
455 | |
421406a4 |
456 | \S{faq-startsess}{Question} How can I create a \i{Windows shortcut} to |
70706890 |
457 | start a particular saved session directly? |
ee46ef84 |
458 | |
459 | To run a PuTTY session saved under the name \q{\cw{mysession}}, |
460 | create a Windows shortcut that invokes PuTTY with a command line |
461 | like |
462 | |
80969352 |
463 | \c \path\name\to\putty.exe -load "mysession" |
a58b605b |
464 | |
465 | (Note: prior to 0.53, the syntax was \c{@session}. This is now |
466 | deprecated and may be removed at some point.) |
ee46ef84 |
467 | |
a1d2976b |
468 | \S{faq-startssh}{Question} How can I start an SSH session straight |
70706890 |
469 | from the command line? |
ee46ef84 |
470 | |
471 | Use the command line \c{putty -ssh host.name}. Alternatively, create |
472 | a saved session that specifies the SSH protocol, and start the saved |
473 | session as shown in \k{faq-startsess}. |
474 | |
421406a4 |
475 | \S{faq-cutpaste}{Question} How do I \i{copy and paste} between PuTTY and |
70706890 |
476 | other Windows applications? |
ee46ef84 |
477 | |
478 | Copy and paste works similarly to the X Window System. You use the |
479 | left mouse button to select text in the PuTTY window. The act of |
480 | selection \e{automatically} copies the text to the clipboard: there |
481 | is no need to press Ctrl-Ins or Ctrl-C or anything else. In fact, |
482 | pressing Ctrl-C will send a Ctrl-C character to the other end of |
483 | your connection (just like it does the rest of the time), which may |
484 | have unpleasant effects. The \e{only} thing you need to do, to copy |
485 | text to the clipboard, is to select it. |
486 | |
487 | To paste the clipboard contents into a PuTTY window, by default you |
488 | click the right mouse button. If you have a three-button mouse and |
489 | are used to X applications, you can configure pasting to be done by |
490 | the middle button instead, but this is not the default because most |
491 | Windows users don't have a middle button at all. |
492 | |
493 | You can also paste by pressing Shift-Ins. |
494 | |
a1d2976b |
495 | \S{faq-options}{Question} How do I use all PuTTY's features (public |
a58b605b |
496 | keys, proxying, cipher selection, etc.) in PSCP, PSFTP and Plink? |
497 | |
498 | Most major features (e.g., public keys, port forwarding) are available |
499 | through command line options. See the documentation. |
72be5b5e |
500 | |
a58b605b |
501 | Not all features are accessible from the command line yet, although |
502 | we'd like to fix this. In the meantime, you can use most of |
72be5b5e |
503 | PuTTY's features if you create a PuTTY saved session, and then use |
504 | the name of the saved session on the command line in place of a |
505 | hostname. This works for PSCP, PSFTP and Plink (but don't expect |
506 | port forwarding in the file transfer applications!). |
f2003e32 |
507 | |
a1d2976b |
508 | \S{faq-pscp}{Question} How do I use PSCP.EXE? When I double-click it |
70706890 |
509 | gives me a command prompt window which then closes instantly. |
ee46ef84 |
510 | |
511 | PSCP is a command-line application, not a GUI application. If you |
512 | run it without arguments, it will simply print a help message and |
513 | terminate. |
514 | |
515 | To use PSCP properly, run it from a Command Prompt window. See |
516 | \k{pscp} in the documentation for more details. |
517 | |
421406a4 |
518 | \S{faq-pscp-spaces}{Question} \I{spaces in filenames}How do I use |
519 | PSCP to copy a file whose name has spaces in? |
ee46ef84 |
520 | |
521 | If PSCP is using the traditional SCP protocol, this is confusing. If |
522 | you're specifying a file at the local end, you just use one set of |
523 | quotes as you would normally do: |
524 | |
525 | \c pscp "local filename with spaces" user@host: |
526 | \c pscp user@host:myfile "local filename with spaces" |
527 | |
528 | But if the filename you're specifying is on the \e{remote} side, you |
529 | have to use backslashes and two sets of quotes: |
530 | |
531 | \c pscp user@host:"\"remote filename with spaces\"" local_filename |
532 | \c pscp local_filename user@host:"\"remote filename with spaces\"" |
533 | |
534 | Worse still, in a remote-to-local copy you have to specify the local |
535 | file name explicitly, otherwise PSCP will complain that they don't |
536 | match (unless you specified the \c{-unsafe} option). The following |
537 | command will give an error message: |
538 | |
539 | \c c:\>pscp user@host:"\"oo er\"" . |
e9cee352 |
540 | \c warning: remote host tried to write to a file called 'oo er' |
541 | \c when we requested a file called '"oo er"'. |
ee46ef84 |
542 | |
e9cee352 |
543 | Instead, you need to specify the local file name in full: |
544 | |
545 | \c c:\>pscp user@host:"\"oo er\"" "oo er" |
546 | |
ee46ef84 |
547 | If PSCP is using the newer SFTP protocol, none of this is a problem, |
548 | and all filenames with spaces in are specified using a single pair |
549 | of quotes in the obvious way: |
550 | |
551 | \c pscp "local file" user@host: |
552 | \c pscp user@host:"remote file" . |
553 | |
554 | \H{faq-trouble} Troubleshooting |
555 | |
babac7bd |
556 | \S{faq-incorrect-mac}{Question} Why do I see \q{Incorrect MAC |
557 | received on packet}? |
ee46ef84 |
558 | |
f348999d |
559 | One possible cause of this that used to be common is a bug in old |
2e85c969 |
560 | SSH-2 servers distributed by \cw{ssh.com}. (This is not the only |
f348999d |
561 | possible cause; see \k{errors-crc} in the documentation.) |
2e85c969 |
562 | Version 2.3.0 and below of their SSH-2 server |
ee46ef84 |
563 | constructs Message Authentication Codes in the wrong way, and |
564 | expects the client to construct them in the same wrong way. PuTTY |
565 | constructs the MACs correctly by default, and hence these old |
566 | servers will fail to work with it. |
567 | |
32c37ecd |
568 | If you are using PuTTY version 0.52 or better, this should work |
569 | automatically: PuTTY should detect the buggy servers from their |
570 | version number announcement, and automatically start to construct |
571 | its MACs in the same incorrect manner as they do, so it will be able |
572 | to work with them. |
ee46ef84 |
573 | |
32c37ecd |
574 | If you are using PuTTY version 0.51 or below, you can enable the |
575 | workaround by going to the SSH panel and ticking the box labelled |
e4c398b4 |
576 | \q{Imitate SSH2 MAC bug}. It's possible that you might have to do |
32c37ecd |
577 | this with 0.52 as well, if a buggy server exists that PuTTY doesn't |
578 | know about. |
ee46ef84 |
579 | |
421406a4 |
580 | In this context MAC stands for \ii{Message Authentication Code}. It's a |
b7e2c163 |
581 | cryptographic term, and it has nothing at all to do with Ethernet |
582 | MAC (Media Access Control) addresses. |
583 | |
67325335 |
584 | \S{faq-pscp-protocol}{Question} Why do I see \q{Fatal: Protocol |
585 | error: Expected control record} in PSCP? |
586 | |
587 | This happens because PSCP was expecting to see data from the server |
588 | that was part of the PSCP protocol exchange, and instead it saw data |
589 | that it couldn't make any sense of at all. |
590 | |
421406a4 |
591 | This almost always happens because the \i{startup scripts} in your |
67325335 |
592 | account on the server machine are generating output. This is |
593 | impossible for PSCP, or any other SCP client, to work around. You |
594 | should never use startup files (\c{.bashrc}, \c{.cshrc} and so on) |
595 | which generate output in non-interactive sessions. |
596 | |
597 | This is not actually a PuTTY problem. If PSCP fails in this way, |
598 | then all other SCP clients are likely to fail in exactly the same |
599 | way. The problem is at the server end. |
600 | |
421406a4 |
601 | \S{faq-colours}{Question} I clicked on a colour in the \ii{Colours} |
70706890 |
602 | panel, and the colour didn't change in my terminal. |
ee46ef84 |
603 | |
604 | That isn't how you're supposed to use the Colours panel. |
605 | |
606 | During the course of a session, PuTTY potentially uses \e{all} the |
607 | colours listed in the Colours panel. It's not a question of using |
608 | only one of them and you choosing which one; PuTTY will use them |
609 | \e{all}. The purpose of the Colours panel is to let you adjust the |
610 | appearance of all the colours. So to change the colour of the |
611 | cursor, for example, you would select \q{Cursor Colour}, press the |
612 | \q{Modify} button, and select a new colour from the dialog box that |
613 | appeared. Similarly, if you want your session to appear in green, |
614 | you should select \q{Default Foreground} and press \q{Modify}. |
615 | Clicking on \q{ANSI Green} won't turn your session green; it will |
616 | only allow you to adjust the \e{shade} of green used when PuTTY is |
617 | instructed by the server to display green text. |
618 | |
421406a4 |
619 | \S{faq-winsock2}{Question} Plink on \i{Windows 95} says it can't find |
620 | \i\cw{WS2_32.DLL}. |
ee46ef84 |
621 | |
622 | Plink requires the extended Windows network library, WinSock version |
623 | 2. This is installed as standard on Windows 98 and above, and on |
624 | Windows NT, and even on later versions of Windows 95; but early |
625 | Win95 installations don't have it. |
626 | |
627 | In order to use Plink on these systems, you will need to download |
628 | the |
629 | \W{http://www.microsoft.com/windows95/downloads/contents/wuadmintools/s_wunetworkingtools/w95sockets2/}{WinSock 2 upgrade}: |
630 | |
35cffede |
631 | \c http://www.microsoft.com/windows95/downloads/contents/ |
632 | \c wuadmintools/s_wunetworkingtools/w95sockets2/ |
ee46ef84 |
633 | |
2e85c969 |
634 | \S{faq-outofmem}{Question} After trying to establish an SSH-2 |
421406a4 |
635 | connection, PuTTY says \q{\ii{Out of memory}} and dies. |
ee46ef84 |
636 | |
637 | If this happens just while the connection is starting up, this often |
638 | indicates that for some reason the client and server have failed to |
639 | establish a session encryption key. Somehow, they have performed |
640 | calculations that should have given each of them the same key, but |
641 | have ended up with different keys; so data encrypted by one and |
642 | decrypted by the other looks like random garbage. |
643 | |
644 | This causes an \q{out of memory} error because the first encrypted |
645 | data PuTTY expects to see is the length of an SSH message. Normally |
646 | this will be something well under 100 bytes. If the decryption has |
647 | failed, PuTTY will see a completely random length in the region of |
648 | two \e{gigabytes}, and will try to allocate enough memory to store |
649 | this non-existent message. This will immediately lead to it thinking |
650 | it doesn't have enough memory, and panicking. |
651 | |
652 | If this happens to you, it is quite likely to still be a PuTTY bug |
653 | and you should report it (although it might be a bug in your SSH |
654 | server instead); but it doesn't necessarily mean you've actually run |
655 | out of memory. |
656 | |
9accb45d |
657 | \S{faq-outofmem2}{Question} When attempting a file transfer, either |
421406a4 |
658 | PSCP or PSFTP says \q{\ii{Out of memory}} and dies. |
9accb45d |
659 | |
421406a4 |
660 | This is almost always caused by your \i{login scripts} on the server |
9accb45d |
661 | generating output. PSCP or PSFTP will receive that output when they |
662 | were expecting to see the start of a file transfer protocol, and |
663 | they will attempt to interpret the output as file-transfer protocol. |
664 | This will usually lead to an \q{out of memory} error for much the |
665 | same reasons as given in \k{faq-outofmem}. |
666 | |
667 | This is a setup problem in your account on your server, \e{not} a |
668 | PSCP/PSFTP bug. Your login scripts should \e{never} generate output |
669 | during non-interactive sessions; secure file transfer is not the |
670 | only form of remote access that will break if they do. |
671 | |
672 | On Unix, a simple fix is to ensure that all the parts of your login |
673 | script that might generate output are in \c{.profile} (if you use a |
674 | Bourne shell derivative) or \c{.login} (if you use a C shell). |
675 | Putting them in more general files such as \c{.bashrc} or \c{.cshrc} |
676 | is liable to lead to problems. |
677 | |
7b24f677 |
678 | \S{faq-psftp-slow}{Question} PSFTP transfers files much slower than PSCP. |
9accb45d |
679 | |
b7280cfe |
680 | The throughput of PSFTP 0.54 should be much better than 0.53b and |
681 | prior; we've added code to the SFTP backend to queue several blocks |
682 | of data rather than waiting for an acknowledgement for each. (The |
683 | SCP backend did not suffer from this performance issue because SCP |
684 | is a much simpler protocol.) |
9accb45d |
685 | |
a1d2976b |
686 | \S{faq-bce}{Question} When I run full-colour applications, I see |
948c614b |
687 | areas of black space where colour ought to be, or vice versa. |
f1453e5c |
688 | |
421406a4 |
689 | You almost certainly need to change the \q{Use \i{background colour} to |
948c614b |
690 | erase screen} setting in the Terminal panel. If there is too much |
691 | black space (the commoner situation), you should enable it, while if |
692 | there is too much colour, you should disable it. (See \k{config-erase}.) |
693 | |
694 | In old versions of PuTTY, this was disabled by default, and would not |
695 | take effect until you reset the terminal (see \k{faq-resetterm}). |
696 | Since 0.54, it is enabled by default, and changes take effect |
697 | immediately. |
f1453e5c |
698 | |
a1d2976b |
699 | \S{faq-resetterm}{Question} When I change some terminal settings, |
70706890 |
700 | nothing happens. |
f1453e5c |
701 | |
421406a4 |
702 | Some of the terminal options (notably \ii{Auto Wrap} and |
f1453e5c |
703 | background-colour screen erase) actually represent the \e{default} |
704 | setting, rather than the currently active setting. The server can |
705 | send sequences that modify these options in mid-session, but when |
706 | the terminal is reset (by server action, or by you choosing \q{Reset |
707 | Terminal} from the System menu) the defaults are restored. |
708 | |
5bcf5d50 |
709 | In versions 0.53b and prior, if you change one of these options in |
710 | the middle of a session, you will find that the change does not |
711 | immediately take effect. It will only take effect once you reset |
712 | the terminal. |
713 | |
e6c7a73a |
714 | In version 0.54, the behaviour has changed - changes to these |
715 | settings take effect immediately. |
f1453e5c |
716 | |
a1d2976b |
717 | \S{faq-idleout}{Question} My PuTTY sessions unexpectedly close after |
421406a4 |
718 | they are \I{idle connections}idle for a while. |
ee46ef84 |
719 | |
421406a4 |
720 | Some types of \i{firewall}, and almost any router doing Network Address |
721 | Translation (\i{NAT}, also known as IP masquerading), will forget about |
ee46ef84 |
722 | a connection through them if the connection does nothing for too |
723 | long. This will cause the connection to be rudely cut off when |
724 | contact is resumed. |
725 | |
726 | You can try to combat this by telling PuTTY to send \e{keepalives}: |
727 | packets of data which have no effect on the actual session, but |
728 | which reassure the router or firewall that the network connection is |
729 | still active and worth remembering about. |
730 | |
731 | Keepalives don't solve everything, unfortunately; although they |
732 | cause greater robustness against this sort of router, they can also |
733 | cause a \e{loss} of robustness against network dropouts. See |
734 | \k{config-keepalive} in the documentation for more discussion of |
735 | this. |
736 | |
a1d2976b |
737 | \S{faq-timeout}{Question} PuTTY's network connections time out too |
421406a4 |
738 | quickly when \I{breaks in connectivity}network connectivity is |
739 | temporarily lost. |
ee46ef84 |
740 | |
741 | This is a Windows problem, not a PuTTY problem. The timeout value |
742 | can't be set on per application or per session basis. To increase |
743 | the TCP timeout globally, you need to tinker with the Registry. |
744 | |
8ac4ce9f |
745 | On Windows 95, 98 or ME, the registry key you need to create or |
746 | change is |
ee46ef84 |
747 | |
748 | \c HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\ |
749 | \c MSTCP\MaxDataRetries |
750 | |
751 | (it must be of type DWORD in Win95, or String in Win98/ME). |
8ac4ce9f |
752 | (See MS Knowledge Base article |
753 | \W{http://support.microsoft.com/default.aspx?scid=kb;en-us;158474}{158474} |
754 | for more information.) |
ee46ef84 |
755 | |
8e5037f6 |
756 | On Windows NT, 2000, or XP, the registry key to create or change is |
ee46ef84 |
757 | |
758 | \c HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\ |
759 | \c Parameters\TcpMaxDataRetransmissions |
760 | |
761 | and it must be of type DWORD. |
8e5037f6 |
762 | (See MS Knowledge Base articles |
8ac4ce9f |
763 | \W{http://support.microsoft.com/default.aspx?scid=kb;en-us;120642}{120642} |
8e5037f6 |
764 | and |
765 | \W{http://support.microsoft.com/default.aspx?scid=kb;en-us;314053}{314053} |
8ac4ce9f |
766 | for more information.) |
ee46ef84 |
767 | |
768 | Set the key's value to something like 10. This will cause Windows to |
769 | try harder to keep connections alive instead of abandoning them. |
770 | |
a1d2976b |
771 | \S{faq-puttyputty}{Question} When I \cw{cat} a binary file, I get |
b03dda39 |
772 | \q{PuTTYPuTTYPuTTY} on my command line. |
ee46ef84 |
773 | |
a5a6cb30 |
774 | Don't do that, then. |
ee46ef84 |
775 | |
776 | This is designed behaviour; when PuTTY receives the character |
777 | Control-E from the remote server, it interprets it as a request to |
778 | identify itself, and so it sends back the string \q{\cw{PuTTY}} as |
779 | if that string had been entered at the keyboard. Control-E should |
780 | only be sent by programs that are prepared to deal with the |
781 | response. Writing a binary file to your terminal is likely to output |
782 | many Control-E characters, and cause this behaviour. Don't do it. |
783 | It's a bad plan. |
784 | |
a5a6cb30 |
785 | To mitigate the effects, you could configure the answerback string |
786 | to be empty (see \k{config-answerback}); but writing binary files to |
787 | your terminal is likely to cause various other unpleasant behaviour, |
788 | so this is only a small remedy. |
789 | |
421406a4 |
790 | \S{faq-wintitle}{Question} When I \cw{cat} a binary file, my \i{window |
791 | title} changes to a nonsense string. |
ee46ef84 |
792 | |
a5a6cb30 |
793 | Don't do that, then. |
ee46ef84 |
794 | |
795 | It is designed behaviour that PuTTY should have the ability to |
796 | adjust the window title on instructions from the server. Normally |
797 | the control sequence that does this should only be sent |
798 | deliberately, by programs that know what they are doing and intend |
799 | to put meaningful text in the window title. Writing a binary file to |
800 | your terminal runs the risk of sending the same control sequence by |
801 | accident, and cause unexpected changes in the window title. Don't do |
802 | it. |
803 | |
e81024f9 |
804 | \S{faq-password-fails}{Question} My \i{keyboard} stops working once |
805 | PuTTY displays the \i{password prompt}. |
59c1f1f6 |
806 | |
807 | No, it doesn't. PuTTY just doesn't display the password you type, so |
808 | that someone looking at your screen can't see what it is. |
809 | |
810 | Unlike the Windows login prompts, PuTTY doesn't display the password |
811 | as a row of asterisks either. This is so that someone looking at |
812 | your screen can't even tell how \e{long} your password is, which |
813 | might be valuable information. |
814 | |
e81024f9 |
815 | \S{faq-keyboard}{Question} One or more \I{keyboard}\i{function keys} |
816 | don't do what I expected in a server-side application. |
b5bee048 |
817 | |
818 | If you've already tried all the relevant options in the PuTTY |
819 | Keyboard panel, you may need to mail the PuTTY maintainers and ask. |
820 | |
821 | It is \e{not} usually helpful just to tell us which application, |
822 | which server operating system, and which key isn't working; in order |
823 | to replicate the problem we would need to have a copy of every |
824 | operating system, and every application, that anyone has ever |
825 | complained about. |
826 | |
827 | PuTTY responds to function key presses by sending a sequence of |
828 | control characters to the server. If a function key isn't doing what |
829 | you expect, it's likely that the character sequence your application |
830 | is expecting to receive is not the same as the one PuTTY is sending. |
831 | Therefore what we really need to know is \e{what} sequence the |
832 | application is expecting. |
833 | |
834 | The simplest way to investigate this is to find some other terminal |
835 | environment, in which that function key \e{does} work; and then |
836 | investigate what sequence the function key is sending in that |
e81024f9 |
837 | situation. One reasonably easy way to do this on a \i{Unix} system is to |
838 | type the command \i\c{cat}, and then press the function key. This is |
b5bee048 |
839 | likely to produce output of the form \c{^[[11~}. You can also do |
840 | this in PuTTY, to find out what sequence the function key is |
841 | producing in that. Then you can mail the PuTTY maintainers and tell |
842 | us \q{I wanted the F1 key to send \c{^[[11~}, but instead it's |
843 | sending \c{^[OP}, can this be done?}, or something similar. |
844 | |
845 | You should still read the |
846 | \W{http://www.chiark.greenend.org.uk/~sgtatham/putty/feedback.html}{Feedback |
847 | page} on the PuTTY website (also provided as \k{feedback} in the |
848 | manual), and follow the guidelines contained in that. |
849 | |
941d39e2 |
850 | \S{faq-openssh-bad-openssl}{Question} Since my SSH server was upgraded |
421406a4 |
851 | to \i{OpenSSH} 3.1p1/3.4p1, I can no longer connect with PuTTY. |
1d2a9c9c |
852 | |
853 | There is a known problem when OpenSSH has been built against an |
854 | incorrect version of OpenSSL; the quick workaround is to configure |
855 | PuTTY to use SSH protocol 2 and the Blowfish cipher. |
856 | |
941d39e2 |
857 | For more details and OpenSSH patches, see |
858 | \W{http://bugzilla.mindrot.org/show_bug.cgi?id=138}{bug 138} in the |
859 | OpenSSH BTS. |
860 | |
1d2a9c9c |
861 | This is not a PuTTY-specific problem; if you try to connect with |
941d39e2 |
862 | another client you'll likely have similar problems. (Although PuTTY's |
863 | default cipher differs from many other clients.) |
1d2a9c9c |
864 | |
941d39e2 |
865 | \e{OpenSSH 3.1p1:} configurations known to be broken (and symptoms): |
1d2a9c9c |
866 | |
3a115fdd |
867 | \b SSH-2 with AES cipher (PuTTY says \q{Assertion failed! Expression: |
868 | (len & 15) == 0} in \cw{sshaes.c}, or \q{Out of memory}, or crashes) |
1d2a9c9c |
869 | |
3a115fdd |
870 | \b SSH-2 with 3DES (PuTTY says \q{Incorrect MAC received on packet}) |
9712b085 |
871 | |
3a115fdd |
872 | \b SSH-1 with Blowfish (PuTTY says \q{Incorrect CRC received on |
873 | packet}) |
1d2a9c9c |
874 | |
2e85c969 |
875 | \b SSH-1 with 3DES |
1d2a9c9c |
876 | |
2e85c969 |
877 | \e{OpenSSH 3.4p1:} as of 3.4p1, only the problem with SSH-1 and |
941d39e2 |
878 | Blowfish remains. Rebuild your server, apply the patch linked to from |
879 | bug 138 above, or use another cipher (e.g., 3DES) instead. |
59f76022 |
880 | |
46ccbe20 |
881 | \e{Other versions:} we occasionally get reports of the same symptom |
882 | and workarounds with older versions of OpenSSH, although it's not |
883 | clear the underlying cause is the same. |
884 | |
3a115fdd |
885 | \S{faq-ssh2key-ssh1conn}{Question} Why do I see \q{Couldn't load |
886 | private key from ...}? Why can PuTTYgen load my key but not PuTTY? |
1bb76745 |
887 | |
888 | It's likely that you've generated an SSH protocol 2 key with PuTTYgen, |
2e85c969 |
889 | but you're trying to use it in an SSH-1 connection. SSH-1 and SSH-2 keys |
1bb76745 |
890 | have different formats, and (at least in 0.52) PuTTY's reporting of a |
891 | key in the wrong format isn't optimal. |
892 | |
2e85c969 |
893 | To connect using SSH-2 to a server that supports both versions, you |
1bb76745 |
894 | need to change the configuration from the default (see \k{faq-ssh2}). |
895 | |
421406a4 |
896 | \S{faq-rh8-utf8}{Question} When I'm connected to a \i{Red Hat Linux} 8.0 |
2c4b913d |
897 | system, some characters don't display properly. |
898 | |
899 | A common complaint is that hyphens in man pages show up as a-acute. |
900 | |
421406a4 |
901 | With release 8.0, Red Hat appear to have made \i{UTF-8} the default |
2c4b913d |
902 | character set. There appears to be no way for terminal emulators such |
903 | as PuTTY to know this (as far as we know, the appropriate escape |
904 | sequence to switch into UTF-8 mode isn't sent). |
905 | |
906 | A fix is to configure sessions to RH8 systems to use UTF-8 |
907 | translation - see \k{config-charset} in the documentation. (Note that |
908 | if you use \q{Change Settings}, changes may not take place immediately |
909 | - see \k{faq-resetterm}.) |
910 | |
911 | If you really want to change the character set used by the server, the |
912 | right place is \c{/etc/sysconfig/i18n}, but this shouldn't be |
913 | necessary. |
914 | |
b86e68d8 |
915 | \S{faq-screen}{Question} Since I upgraded to PuTTY 0.54, the |
916 | scrollback has stopped working when I run \c{screen}. |
917 | |
918 | PuTTY's terminal emulator has always had the policy that when the |
421406a4 |
919 | \q{\i{alternate screen}} is in use, nothing is added to the scrollback. |
b86e68d8 |
920 | This is because the usual sorts of programs which use the alternate |
921 | screen are things like text editors, which tend to scroll back and |
922 | forth in the same document a lot; so (a) they would fill up the |
923 | scrollback with a large amount of unhelpfully disordered text, and |
924 | (b) they contain their \e{own} method for the user to scroll back to |
925 | the bit they were interested in. We have generally found this policy |
926 | to do the Right Thing in almost all situations. |
927 | |
928 | Unfortunately, \c{screen} is one exception: it uses the alternate |
929 | screen, but it's still usually helpful to have PuTTY's scrollback |
930 | continue working. The simplest solution is to go to the Features |
931 | control panel and tick \q{Disable switching to alternate terminal |
932 | screen}. (See \k{config-features-altscreen} for more details.) |
f08afc59 |
933 | Alternatively, you can tell \c{screen} itself not to use the |
934 | alternate screen: the |
935 | \W{http://www4.informatik.uni-erlangen.de/~jnweiger/screen-faq.html}{\c{screen} |
936 | FAQ} suggests adding the line \cq{termcapinfo xterm ti@:te@} to your |
937 | \cw{.screenrc} file. |
b86e68d8 |
938 | |
939 | The reason why this only started to be a problem in 0.54 is because |
940 | \c{screen} typically uses an unusual control sequence to switch to |
941 | the alternate screen, and previous versions of PuTTY did not support |
942 | this sequence. |
943 | |
421406a4 |
944 | \S{faq-alternate-localhost}{Question} Since I upgraded \i{Windows XP} |
85c598bf |
945 | to Service Pack 2, I can't use addresses like \cw{127.0.0.2}. |
946 | |
421406a4 |
947 | Some people who ask PuTTY to listen on \i{localhost} addresses other |
948 | than \cw{127.0.0.1} to forward services such as \i{SMB} and \i{Windows |
949 | Terminal Services} have found that doing so no longer works since |
85c598bf |
950 | they upgraded to WinXP SP2. |
951 | |
0a05eecb |
952 | This is apparently an issue with SP2 that is acknowledged by Microsoft |
953 | in MS Knowledge Base article |
85c598bf |
954 | \W{http://support.microsoft.com/default.aspx?scid=kb;en-us;884020}{884020}. |
a510ac14 |
955 | The article links to a fix you can download. |
85c598bf |
956 | |
5ac88186 |
957 | (\e{However}, we've been told that SP2 \e{also} fixes the bug that |
958 | means you need to use non-\cw{127.0.0.1} addresses to forward |
000cae2e |
959 | Terminal Services in the first place.) |
5ac88186 |
960 | |
811527db |
961 | \S{faq-missing-slash}{Question} PSFTP commands seem to be missing a |
962 | directory separator (slash). |
963 | |
964 | Some people have reported the following incorrect behaviour with |
965 | PSFTP: |
966 | |
967 | \c psftp> pwd |
968 | \e iii |
969 | \c Remote directory is /dir1/dir2 |
970 | \c psftp> get filename.ext |
971 | \e iiiiiiiiiiiiiiii |
972 | \c /dir1/dir2filename.ext: no such file or directory |
973 | |
974 | This is not a bug in PSFTP. There is a known bug in some versions of |
421406a4 |
975 | portable \i{OpenSSH} |
811527db |
976 | (\W{http://bugzilla.mindrot.org/show_bug.cgi?id=697}{bug 697}) that |
977 | causes these symptoms; it appears to have been introduced around |
978 | 3.7.x. It manifests only on certain platforms (AIX is what has been |
979 | reported to us). |
980 | |
981 | There is a patch for OpenSSH attached to that bug; it's also fixed in |
982 | recent versions of portable OpenSSH (from around 3.8). |
983 | |
b493cd11 |
984 | \S{faq-connaborted}{Question} Do you want to hear about \q{Software |
985 | caused connection abort}? |
6b39d356 |
986 | |
987 | In the documentation for PuTTY 0.53 and 0.53b, we mentioned that we'd |
988 | like to hear about any occurrences of this error. Since the release |
989 | of PuTTY 0.54, however, we've been convinced that this error doesn't |
990 | indicate that PuTTY's doing anything wrong, and we don't need to hear |
991 | about further occurrences. See \k{errors-connaborted} for our current |
992 | documentation of this error. |
993 | |
3ba2d921 |
994 | \S{faq-rekey}{Question} My SSH-2 session \I{locking up, SSH-2 |
995 | sessions}locks up for a few seconds every so often. |
996 | |
997 | Recent versions of PuTTY automatically initiate \i{repeat key |
998 | exchange} once per hour, to improve session security. If your client |
999 | or server machine is slow, you may experience this as a delay of |
1000 | anything up to thirty seconds or so. |
1001 | |
1002 | These \I{delays, in SSH-2 sessions}delays are inconvenient, but they |
1003 | are there for your protection. If they really cause you a problem, |
1004 | you can choose to turn off periodic rekeying using the \q{Kex} |
1005 | configuration panel (see \k{config-ssh-kex}), but be aware that you |
1006 | will be sacrificing security for this. (Falling back to SSH-1 would |
1007 | also remove the delays, but would lose a \e{lot} more security |
1008 | still. We do not recommend it.) |
1009 | |
7090f35e |
1010 | \S{faq-xpwontrun}{Question} PuTTY fails to start up. Windows claims that |
1011 | \q{the application configuration is incorrect}. |
1012 | |
1013 | This is caused by a bug in certain versions of \i{Windows XP} which is |
1014 | triggered by PuTTY 0.58. It can be avoided by installing |
1015 | Service Pack 2, by using a different version of PuTTY, or by installing |
1016 | a special \i{manifest file} alongside the PuTTY executable. |
1017 | The |
1018 | \W{http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/xp-wont-run}{\q{xp-wont-run}} |
1019 | entry in PuTTY's wishlist has more details. |
1020 | |
ee46ef84 |
1021 | \H{faq-secure} Security questions |
1022 | |
a1d2976b |
1023 | \S{faq-publicpc}{Question} Is it safe for me to download PuTTY and |
70706890 |
1024 | use it on a public PC? |
ee46ef84 |
1025 | |
1026 | It depends on whether you trust that PC. If you don't trust the |
1027 | public PC, don't use PuTTY on it, and don't use any other software |
1028 | you plan to type passwords into either. It might be watching your |
1029 | keystrokes, or it might tamper with the PuTTY binary you download. |
1030 | There is \e{no} program safe enough that you can run it on an |
1031 | actively malicious PC and get away with typing passwords into it. |
1032 | |
1033 | If you do trust the PC, then it's probably OK to use PuTTY on it |
1034 | (but if you don't trust the network, then the PuTTY download might |
1035 | be tampered with, so it would be better to carry PuTTY with you on a |
1036 | floppy). |
1037 | |
a1d2976b |
1038 | \S{faq-cleanup}{Question} What does PuTTY leave on a system? How can |
421406a4 |
1039 | I \i{clean up} after it? |
ee46ef84 |
1040 | |
1041 | PuTTY will leave some Registry entries, and a random seed file, on |
1042 | the PC (see \k{faq-settings}). If you are using PuTTY on a public |
1043 | PC, or somebody else's PC, you might want to clean these up when you |
1044 | leave. You can do that automatically, by running the command |
9310cb7d |
1045 | \c{putty -cleanup}. (Note that this only removes settings for |
1046 | the currently logged-in user on \i{multi-user systems}.) |
1047 | |
1048 | If PuTTY was installed from the installer package, it will also |
c35ff6c8 |
1049 | appear in \q{Add/Remove Programs}. Older versions of the uninstaller |
1050 | do not remove the above-mentioned registry entries and file. |
ee46ef84 |
1051 | |
421406a4 |
1052 | \S{faq-dsa}{Question} How come PuTTY now supports \i{DSA}, when the |
70706890 |
1053 | website used to say how insecure it was? |
ee46ef84 |
1054 | |
1055 | DSA has a major weakness \e{if badly implemented}: it relies on a |
1056 | random number generator to far too great an extent. If the random |
1057 | number generator produces a number an attacker can predict, the DSA |
1058 | private key is exposed - meaning that the attacker can log in as you |
1059 | on all systems that accept that key. |
1060 | |
1061 | The PuTTY policy changed because the developers were informed of |
1062 | ways to implement DSA which do not suffer nearly as badly from this |
1063 | weakness, and indeed which don't need to rely on random numbers at |
1064 | all. For this reason we now believe PuTTY's DSA implementation is |
1065 | probably OK. However, if you have the choice, we still recommend you |
1066 | use RSA instead. |
1067 | |
ee4b471f |
1068 | \S{faq-virtuallock}{Question} Couldn't Pageant use |
1069 | \cw{VirtualLock()} to stop private keys being written to disk? |
f9908cf7 |
1070 | |
ee4b471f |
1071 | Unfortunately not. The \cw{VirtualLock()} function in the Windows |
1072 | API doesn't do a proper job: it may prevent small pieces of a |
1073 | process's memory from being paged to disk while the process is |
1074 | running, but it doesn't stop the process's memory as a whole from |
1075 | being swapped completely out to disk when the process is long-term |
1076 | inactive. And Pageant spends most of its time inactive. |
f9908cf7 |
1077 | |
ee46ef84 |
1078 | \H{faq-admin} Administrative questions |
1079 | |
a1d2976b |
1080 | \S{faq-domain}{Question} Would you like me to register you a nicer |
70706890 |
1081 | domain name? |
ee46ef84 |
1082 | |
1083 | No, thank you. Even if you can find one (most of them seem to have |
1084 | been registered already, by people who didn't ask whether we |
1085 | actually wanted it before they applied), we're happy with the PuTTY |
1086 | web site being exactly where it is. It's not hard to find (just type |
1087 | \q{putty} into \W{http://www.google.com/}{google.com} and we're the |
1088 | first link returned), and we don't believe the administrative hassle |
1089 | of moving the site would be worth the benefit. |
1090 | |
1091 | In addition, if we \e{did} want a custom domain name, we would want |
1092 | to run it ourselves, so we knew for certain that it would continue |
1093 | to point where we wanted it, and wouldn't suddenly change or do |
1094 | strange things. Having it registered for us by a third party who we |
1095 | don't even know is not the best way to achieve this. |
1096 | |
a1d2976b |
1097 | \S{faq-webhosting}{Question} Would you like free web hosting for the |
70706890 |
1098 | PuTTY web site? |
ee46ef84 |
1099 | |
1100 | We already have some, thanks. |
1101 | |
34185d04 |
1102 | \S{faq-link}{Question} Would you link to my web site from the PuTTY |
1103 | web site? |
1104 | |
1105 | Only if the content of your web page is of definite direct interest |
1106 | to PuTTY users. If your content is unrelated, or only tangentially |
1107 | related, to PuTTY, then the link would simply be advertising for |
1108 | you. |
1109 | |
1110 | One very nice effect of the Google ranking mechanism is that by and |
1111 | large, the most popular web sites get the highest rankings. This |
1112 | means that when an ordinary person does a search, the top item in |
1113 | the search is very likely to be a high-quality site or the site they |
1114 | actually wanted, rather than the site which paid the most money for |
1115 | its ranking. |
1116 | |
1117 | The PuTTY web site is held in high esteem by Google, for precisely |
1118 | this reason: lots of people have linked to it simply because they |
1119 | like PuTTY, without us ever having to ask anyone to link to us. We |
1120 | feel that it would be an abuse of this esteem to use it to boost the |
1121 | ranking of random advertisers' web sites. If you want your web site |
1122 | to have a high Google ranking, we'd prefer that you achieve this the |
1123 | way we did - by being good enough at what you do that people will |
1124 | link to you simply because they like you. |
1125 | |
b609f258 |
1126 | In particular, we aren't interested in trading links for money (see |
1127 | above), and we \e{certainly} aren't interested in trading links for |
1128 | other links (since we have no advertising on our web site, our |
1129 | Google ranking is not even directly worth anything to us). If we |
1130 | don't want to link to you for free, then we probably won't want to |
1131 | link to you at all. |
1132 | |
34185d04 |
1133 | If you have software based on PuTTY, or specifically designed to |
1134 | interoperate with PuTTY, or in some other way of genuine interest to |
1135 | PuTTY users, then we will probably be happy to add a link to you on |
1136 | our Links page. And if you're running a mirror of the PuTTY web |
1137 | site, we're \e{definitely} interested. |
1138 | |
a1d2976b |
1139 | \S{faq-sourceforge}{Question} Why don't you move PuTTY to |
70706890 |
1140 | SourceForge? |
ee46ef84 |
1141 | |
1142 | Partly, because we don't want to move the web site location (see |
1143 | \k{faq-domain}). |
1144 | |
1145 | Also, security reasons. PuTTY is a security product, and as such it |
1146 | is particularly important to guard the code and the web site against |
1147 | unauthorised modifications which might introduce subtle security |
51e759ee |
1148 | flaws. Therefore, we prefer that the Subversion repository, web site and |
ee46ef84 |
1149 | FTP site remain where they are, under the direct control of system |
1150 | administrators we know and trust personally, rather than being run |
1151 | by a large organisation full of people we've never met and which is |
1152 | known to have had breakins in the past. |
1153 | |
1154 | No offence to SourceForge; I think they do a wonderful job. But |
1155 | they're not ideal for everyone, and in particular they're not ideal |
1156 | for us. |
1157 | |
a1d2976b |
1158 | \S{faq-mailinglist1}{Question} Why can't I subscribe to the |
70706890 |
1159 | putty-bugs mailing list? |
ee46ef84 |
1160 | |
1161 | Because you're not a member of the PuTTY core development team. The |
1162 | putty-bugs mailing list is not a general newsgroup-like discussion |
1163 | forum; it's a contact address for the core developers, and an |
1164 | \e{internal} mailing list for us to discuss things among ourselves. |
1165 | If we opened it up for everybody to subscribe to, it would turn into |
1166 | something more like a newsgroup and we would be completely |
1167 | overwhelmed by the volume of traffic. It's hard enough to keep up |
1168 | with the list as it is. |
1169 | |
a1d2976b |
1170 | \S{faq-mailinglist2}{Question} If putty-bugs isn't a |
70706890 |
1171 | general-subscription mailing list, what is? |
ee46ef84 |
1172 | |
1173 | There isn't one, that we know of. |
1174 | |
be86e512 |
1175 | If someone else wants to set up a mailing list or other forum for |
1176 | PuTTY users to help each other with common problems, that would be |
1177 | fine with us, though the PuTTY team would almost certainly not have the |
87b461db |
1178 | time to read it. It's probably better to use one of the established |
1179 | newsgroups for this purpose (see \k{feedback-other-fora}). |
ee46ef84 |
1180 | |
a1d2976b |
1181 | \S{faq-donations}{Question} How can I donate to PuTTY development? |
ee46ef84 |
1182 | |
1183 | Please, \e{please} don't feel you have to. PuTTY is completely free |
1184 | software, and not shareware. We think it's very important that |
1185 | \e{everybody} who wants to use PuTTY should be able to, whether they |
1186 | have any money or not; so the last thing we would want is for a |
1187 | PuTTY user to feel guilty because they haven't paid us any money. If |
1188 | you want to keep your money, please do keep it. We wouldn't dream of |
1189 | asking for any. |
1190 | |
1191 | Having said all that, if you still really \e{want} to give us money, |
1192 | we won't argue :-) The easiest way for us to accept donations is if |
2244ea7b |
1193 | you send money to \cw{<anakin@pobox.com>} using PayPal |
1194 | (\W{http://www.paypal.com/}\cw{www.paypal.com}). Alternatively, if |
1195 | you don't trust PayPal, you could donate through e-gold |
1196 | (\W{http://www.e-gold.com}\cw{www.e-gold.com}): deposit your |
1197 | donation in account number 174769, then send us e-mail to let us |
1198 | know you've done so (otherwise we might not notice for months!). |
ee46ef84 |
1199 | |
1200 | Small donations (tens of dollars or tens of euros) will probably be |
1201 | spent on beer or curry, which helps motivate our volunteer team to |
1202 | continue doing this for the world. Larger donations will be spent on |
1203 | something that actually helps development, if we can find anything |
9cd3f7b0 |
1204 | (perhaps new hardware, or a copy of Windows XP), but if we can't |
ee46ef84 |
1205 | find anything then we'll just distribute the money among the |
1206 | developers. If you want to be sure your donation is going towards |
1207 | something worthwhile, ask us first. If you don't like these terms, |
1208 | feel perfectly free not to donate. We don't mind. |
1209 | |
150ef9c6 |
1210 | \S{faq-permission}{Question} Can I have permission to put PuTTY on a |
1211 | cover disk / distribute it with other software / etc? |
1212 | |
1213 | Yes. You need not bother asking us explicitly for permission. You |
1214 | already have permission. Redistribution of the unmodified PuTTY |
91ebba83 |
1215 | binary in this way is entirely permitted by our licence (see |
1216 | \k{licence}), and you are welcome to do it as much as you like. |
150ef9c6 |
1217 | |
1218 | If you are distributing PuTTY within your own organisation, or for |
1219 | use with your own product, then we recommend (but do not insist) |
1220 | that you offer your own first-line technical support, to answer |
1221 | questions directly relating to the interaction of PuTTY with your |
1222 | particular environment. If your users mail us directly, we won't be |
1223 | able to give them very much help about things specific to your own |
1224 | setup. |
1225 | |
6894fbe1 |
1226 | \S{faq-indemnity}{Question} Can you sign an agreement indemnifying |
1227 | us against security problems in PuTTY? |
1228 | |
1229 | No! |
1230 | |
1231 | A vendor of physical security products (e.g. locks) might plausibly |
1232 | be willing to accept financial liability for a product that failed |
1233 | to perform as advertised and resulted in damage (e.g. valuables |
1234 | being stolen). The reason they can afford to do this is because they |
1235 | sell a \e{lot} of units, and only a small proportion of them will |
1236 | fail; so they can meet their financial liability out of the income |
1237 | from all the rest of their sales, and still have enough left over to |
1238 | make a profit. Financial liability is intrinsically linked to |
1239 | selling your product for money. |
1240 | |
1241 | There are two reasons why PuTTY is not analogous to a physical lock |
1242 | in this context. One is that software products don't exhibit random |
1243 | variation: \e{if} PuTTY has a security hole (which does happen, |
1244 | although we do our utmost to prevent it and to respond quickly when |
1245 | it does), every copy of PuTTY will have the same hole, so it's |
1246 | likely to affect all the users at the same time. So even if our |
1247 | users were all paying us to use PuTTY, we wouldn't be able to |
1248 | \e{simultaneously} pay every affected user compensation in excess of |
1249 | the amount they had paid us in the first place. It just wouldn't |
1250 | work. |
1251 | |
1252 | The second, much more important, reason is that PuTTY users |
1253 | \e{don't} pay us. The PuTTY team does not have an income; it's a |
1254 | volunteer effort composed of people spending their spare time to try |
1255 | to write useful software. We aren't even a company or any kind of |
1256 | legally recognised organisation. We're just a bunch of people who |
1257 | happen to do some stuff in our spare time. |
1258 | |
1259 | Therefore, to ask us to assume financial liability is to ask us to |
1260 | assume a risk of having to pay it out of our own \e{personal} |
1261 | pockets: out of the same budget from which we buy food and clothes |
1262 | and pay our rent. That's more than we're willing to give. We're |
1263 | already giving a lot of our spare \e{time} to developing software |
1264 | for free; if we had to pay our own \e{money} to do it as well, we'd |
1265 | start to wonder why we were bothering. |
1266 | |
1267 | Free software fundamentally does not work on the basis of financial |
1268 | guarantees. Your guarantee of the software functioning correctly is |
1269 | simply that you have the source code and can check it before you use |
1270 | it. If you want to be sure there aren't any security holes, do a |
1271 | security audit of the PuTTY code, or hire a security engineer if you |
1272 | don't have the necessary skills yourself: instead of trying to |
1273 | ensure you can get compensation in the event of a disaster, try to |
1274 | ensure there isn't a disaster in the first place. |
1275 | |
1276 | If you \e{really} want financial security, see if you can find a |
1277 | security engineer who will take financial responsibility for the |
1278 | correctness of their review. (This might be less likely to suffer |
1279 | from the everything-failing-at-once problem mentioned above, because |
1280 | such an engineer would probably be reviewing a lot of \e{different} |
1281 | products which would tend to fail independently.) Failing that, see |
1282 | if you can persuade an insurance company to insure you against |
1283 | security incidents, and if the insurer demands it as a condition |
1284 | then get our code reviewed by a security engineer they're happy |
1285 | with. |
1286 | |
1287 | \S{faq-permission-form}{Question} Can you sign this form granting us |
1288 | permission to use/distribute PuTTY? |
1289 | |
1290 | If your form contains any clause along the lines of \q{the |
1291 | undersigned represents and warrants}, we're not going to sign it. |
1292 | This is particularly true if it asks us to warrant that PuTTY is |
1293 | secure; see \k{faq-indemnity} for more discussion of this. But it |
1294 | doesn't really matter what we're supposed to be warranting: even if |
1295 | it's something we already believe is true, such as that we don't |
1296 | infringe any third-party copyright, we will not sign a document |
1297 | accepting any legal or financial liability. This is simply because |
1298 | the PuTTY development project has no income out of which to satisfy |
1299 | that liability, or pay legal costs, should it become necessary. We |
1300 | cannot afford to be sued. We are assuring you that \e{we have done |
1301 | our best}; if that isn't good enough for you, tough. |
1302 | |
1303 | The existing PuTTY licence document already gives you permission to |
1304 | use or distribute PuTTY in pretty much any way which does not |
1305 | involve pretending you wrote it or suing us if it goes wrong. We |
1306 | think that really ought to be enough for anybody. |
1307 | |
1308 | See also \k{faq-permission-general} for another reason why we don't |
1309 | want to do this sort of thing. |
1310 | |
1311 | \S{faq-permission-future}{Question} Can you write us a formal notice |
1312 | of permission to use PuTTY? |
1313 | |
1314 | We could, in principle, but it isn't clear what use it would be. If |
1315 | you think there's a serious chance of one of the PuTTY copyright |
1316 | holders suing you (which we don't!), you would presumably want a |
1317 | signed notice from \e{all} of them; and we couldn't provide that |
1318 | even if we wanted to, because many of the copyright holders are |
1319 | people who contributed some code in the past and with whom we |
1320 | subsequently lost contact. Therefore the best we would be able to do |
1321 | \e{even in theory} would be to have the core development team sign |
1322 | the document, which wouldn't guarantee you that some other copyright |
1323 | holder might not sue. |
1324 | |
1325 | See also \k{faq-permission-general} for another reason why we don't |
1326 | want to do this sort of thing. |
1327 | |
1328 | \S{faq-permission-general}{Question} Can you sign \e{anything} for |
1329 | us? |
1330 | |
1331 | Not unless there's an incredibly good reason. |
1332 | |
1333 | We are generally unwilling to set a precedent that involves us |
1334 | having to enter into individual agreements with PuTTY users. We |
1335 | estimate that we have literally \e{millions} of users, and we |
1336 | absolutely would not have time to go round signing specific |
1337 | agreements with every one of them. So if you want us to sign |
1338 | something specific for you, you might usefully stop to consider |
1339 | whether there's anything special that distinguishes you from 999,999 |
1340 | other users, and therefore any reason we should be willing to sign |
1341 | something for you without it setting such a precedent. |
1342 | |
1343 | If your company policy requires you to have an individual agreement |
1344 | with the supplier of any software you use, then your company policy |
1345 | is simply not well suited to using popular free software, and we |
1346 | urge you to consider this as a flaw in your policy. |
1347 | |
1348 | \S{faq-permission-assurance}{Question} If you won't sign anything, |
1349 | can you give us some sort of assurance that you won't make PuTTY |
1350 | closed-source in future? |
1351 | |
1352 | Yes and no. |
1353 | |
1354 | If what you want is an assurance that some \e{current version} of |
1355 | PuTTY which you've already downloaded will remain free, then you |
1356 | already have that assurance: it's called the PuTTY Licence. It |
1357 | grants you permission to use, distribute and copy the software to |
1358 | which it applies; once we've granted that permission (which we |
1359 | have), we can't just revoke it. |
1360 | |
1361 | On the other hand, if you want an assurance that \e{future} versions |
1362 | of PuTTY won't be closed-source, that's more difficult. We could in |
1363 | principle sign a document stating that we would never release a |
1364 | closed-source PuTTY, but that wouldn't assure you that we \e{would} |
1365 | keep releasing \e{open}-source PuTTYs: we would still have the |
1366 | option of ceasing to develop PuTTY at all, which would surely be |
1367 | even worse for you than making it closed-source! (And we almost |
1368 | certainly wouldn't \e{want} to sign a document guaranteeing that we |
1369 | would actually continue to do development work on PuTTY; we |
1370 | certainly wouldn't sign it for free. Documents like that are called |
1371 | contracts of employment, and are generally not signed except in |
1372 | return for a sizeable salary.) |
1373 | |
1374 | If we \e{were} to stop developing PuTTY, or to decide to make all |
1375 | future releases closed-source, then you would still be free to copy |
1376 | the last open release in accordance with the current licence, and in |
1377 | particular you could start your own fork of the project from that |
1378 | release. If this happened, I confidently predict that \e{somebody} |
1379 | would do that, and that some kind of a free PuTTY would continue to |
1380 | be developed. There's already precedent for that sort of thing |
1381 | happening in free software. We can't guarantee that somebody |
1382 | \e{other than you} would do it, of course; you might have to do it |
1383 | yourself. But we can assure you that there would be nothing |
1384 | \e{preventing} anyone from continuing free development if we |
1385 | stopped. |
1386 | |
1387 | (Finally, we can also confidently predict that if we made PuTTY |
1388 | closed-source and someone made an open-source fork, most people |
1389 | would switch to the latter. Therefore, it would be pretty stupid of |
1390 | us to try it.) |
1391 | |
f9908cf7 |
1392 | \H{faq-misc} Miscellaneous questions |
1393 | |
421406a4 |
1394 | \S{faq-openssh}{Question} Is PuTTY a port of \i{OpenSSH}, or based on |
f9908cf7 |
1395 | OpenSSH? |
1396 | |
1397 | No, it isn't. PuTTY is almost completely composed of code written |
1398 | from scratch for PuTTY. The only code we share with OpenSSH is the |
2e85c969 |
1399 | detector for SSH-1 CRC compensation attacks, written by CORE SDI S.A. |
f9908cf7 |
1400 | |
606398fb |
1401 | \S{faq-sillyputty}{Question} Where can I buy silly putty? |
1402 | |
1403 | You're looking at the wrong web site; the only PuTTY we know about |
1404 | here is the name of a computer program. |
1405 | |
1406 | If you want the kind of putty you can buy as an executive toy, the |
1407 | PuTTY team can personally recommend Thinking Putty, which you can |
1408 | buy from Crazy Aaron's Putty World, at |
1409 | \W{http://www.puttyworld.com}\cw{www.puttyworld.com}. |
1410 | |
fa58cf81 |
1411 | \S{faq-meaning}{Question} What does \q{PuTTY} mean? |
ee46ef84 |
1412 | |
fa58cf81 |
1413 | It's the name of a popular SSH and Telnet client. Any other meaning |
1414 | is in the eye of the beholder. It's been rumoured that \q{PuTTY} |
1415 | is the antonym of \q{\cw{getty}}, or that it's the stuff that makes your |
1416 | Windows useful, or that it's a kind of plutonium Teletype. We |
1417 | couldn't possibly comment on such allegations. |
1418 | |
1419 | \S{faq-pronounce}{Question} How do I pronounce \q{PuTTY}? |
1420 | |
1421 | Exactly like the English word \q{putty}, which we pronounce |
65b15d17 |
1422 | /\u02C8{'}p\u028C{V}ti/. |