X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/9dda64599614c85260f2559f6b9688c0e971edb9..c5e438ecf3f6d7b8caab10e43a452f3555149309:/doc/faq.but diff --git a/doc/faq.but b/doc/faq.but index 1aa42760..3459826f 100644 --- a/doc/faq.but +++ b/doc/faq.but @@ -1,4 +1,4 @@ -\versionid $Id: faq.but,v 1.25 2002/05/11 16:45:29 simon Exp $ +\versionid $Id: faq.but,v 1.36 2002/10/10 14:39:35 jacob Exp $ \A{faq} PuTTY FAQ @@ -37,10 +37,9 @@ version 0.52. \S{faq-ssh2-keyfmt}{Question} Does PuTTY support reading OpenSSH or \cw{ssh.com} SSHv2 private key files? -Version 0.52 doesn't, but in the latest development snapshots -PuTTYgen can load OpenSSH private keys. We plan to add an export -feature so that it can save them as well, and we also plan to -support the \cw{ssh.com} key format. +PuTTY doesn't support this natively, but as of 0.53 +PuTTYgen can convert both OpenSSH and \cw{ssh.com} private key +files into PuTTY's format. \S{faq-ssh1}{Question} Does PuTTY support SSH v1? @@ -194,7 +193,7 @@ We do not have ports for any other systems at the present time. If anyone told you we had a Unix port, or an iPaq port, or any other port of PuTTY, they were mistaken. We don't. -\S{faq-wince}{Question} Will there be a port to Windows CE? +\S{faq-wince}{Question} Will there be a port to Windows CE or PocketPC? Probably not in the particularly near future. Despite sharing large parts of the Windows API, in practice WinCE doesn't appear to be @@ -331,7 +330,10 @@ To run a PuTTY session saved under the name \q{\cw{mysession}}, create a Windows shortcut that invokes PuTTY with a command line like -\c \path\name\to\putty.exe @mysession +\c \path\name\to\putty.exe -load mysession + +(Note: prior to 0.53, the syntax was \c{@session}. This is now +deprecated and may be removed at some point.) \S{faq-startssh}{Question} How can I start an SSH session straight from the command line? @@ -366,10 +368,13 @@ forwarding? I can't find the Tunnels panel. This is a new feature in version 0.52. You should upgrade. \S{faq-options}{Question} How do I use all PuTTY's features (public -keys, port forwarding, SSH v2, etc.) in PSCP, PSFTP and Plink? +keys, proxying, cipher selection, etc.) in PSCP, PSFTP and Plink? + +Most major features (e.g., public keys, port forwarding) are available +through command line options. See the documentation. -The command-line tools are currently rather short of command line -options to enable this sort of thing. However, you can use most of +Not all features are accessible from the command line yet, although +we'd like to fix this. In the meantime, you can use most of PuTTY's features if you create a PuTTY saved session, and then use the name of the saved session on the command line in place of a hostname. This works for PSCP, PSFTP and Plink (but don't expect @@ -507,7 +512,7 @@ v2 servers from \cw{ssh.com} will require the key exchange to be repeated one hour after the start of the connection, and PuTTY will get this wrong. -Upgrade to version 0.52 and the problem should go away. +Upgrade to version 0.52 or better and the problem should go away. \S{faq-outofmem}{Question} After trying to establish an SSH 2 connection, PuTTY says \q{Out of memory} and dies. @@ -588,7 +593,7 @@ effect. It will only take effect once you reset the terminal. AltGr key. In PuTTY version 0.51, the AltGr key was broken. Upgrade to version -0.52. +0.52 or better. \S{faq-idleout}{Question} My PuTTY sessions unexpectedly close after they are idle for a while. @@ -713,17 +718,22 @@ You should still read the page} on the PuTTY website (also provided as \k{feedback} in the manual), and follow the guidelines contained in that. -\S{faq-broken-openssh31}{Question} Since my SSH server was upgraded to -OpenSSH 3.1p1, I can no longer connect with PuTTY. +\S{faq-openssh-bad-openssl}{Question} Since my SSH server was upgraded +to OpenSSH 3.1p1/3.4p1, I can no longer connect with PuTTY. There is a known problem when OpenSSH has been built against an incorrect version of OpenSSL; the quick workaround is to configure PuTTY to use SSH protocol 2 and the Blowfish cipher. +For more details and OpenSSH patches, see +\W{http://bugzilla.mindrot.org/show_bug.cgi?id=138}{bug 138} in the +OpenSSH BTS. + This is not a PuTTY-specific problem; if you try to connect with -another client you'll likely have similar problems. +another client you'll likely have similar problems. (Although PuTTY's +default cipher differs from many other clients.) -Configurations known to be broken (and symptoms): +\e{OpenSSH 3.1p1:} configurations known to be broken (and symptoms): \b SSH 2 with AES cipher (PuTTY says "Assertion failed! Expression: (len & 15) == 0" in sshaes.c, or "Out of memory", or crashes) @@ -735,9 +745,24 @@ packet") \b SSH 1 with 3DES -For more details and OpenSSH patches, see -\W{http://bugzilla.mindrot.org/show_bug.cgi?id=138}{bug 138} in the -OpenSSH BTS. +\e{OpenSSH 3.4p1:} as of 3.4p1, only the problem with SSH 1 and +Blowfish remains. Rebuild your server, apply the patch linked to from +bug 138 above, or use another cipher (e.g., 3DES) instead. + +\e{Other versions:} we occasionally get reports of the same symptom +and workarounds with older versions of OpenSSH, although it's not +clear the underlying cause is the same. + +\S{faq-ssh2key-ssh1conn}{Question} Why do I see "Couldn't load private +key from ..."? Why can PuTTYgen load my key but not PuTTY? + +It's likely that you've generated an SSH protocol 2 key with PuTTYgen, +but you're trying to use it in an SSH 1 connection. SSH1 and SSH2 keys +have different formats, and (at least in 0.52) PuTTY's reporting of a +key in the wrong format isn't optimal. + +To connect using SSH 2 to a server that supports both versions, you +need to change the configuration from the default (see \k{faq-ssh2}). \H{faq-secure} Security questions @@ -781,6 +806,16 @@ all. For this reason we now believe PuTTY's DSA implementation is probably OK. However, if you have the choice, we still recommend you use RSA instead. +\S{faq-virtuallock}{Question} Couldn't Pageant use +\cw{VirtualLock()} to stop private keys being written to disk? + +Unfortunately not. The \cw{VirtualLock()} function in the Windows +API doesn't do a proper job: it may prevent small pieces of a +process's memory from being paged to disk while the process is +running, but it doesn't stop the process's memory as a whole from +being swapped completely out to disk when the process is long-term +inactive. And Pageant spends most of its time inactive. + \H{faq-admin} Administrative questions \S{faq-domain}{Question} Would you like me to register you a nicer @@ -878,6 +913,15 @@ developers. If you want to be sure your donation is going towards something worthwhile, ask us first. If you don't like these terms, feel perfectly free not to donate. We don't mind. +\H{faq-misc} Miscellaneous questions + +\S{faq-openssh}{Question} Is PuTTY a port of OpenSSH, or based on +OpenSSH? + +No, it isn't. PuTTY is almost completely composed of code written +from scratch for PuTTY. The only code we share with OpenSSH is the +detector for SSH1 CRC compensation attacks, written by CORE SDI S.A. + \S{faq-sillyputty}{Question} Where can I buy silly putty? You're looking at the wrong web site; the only PuTTY we know about