X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/putty/blobdiff_plain/1d2a9c9caa60dc62a8f510957880cb7941af4c2b..59f76022ba5d26b64fb06b07c947808ef3457052:/doc/faq.but diff --git a/doc/faq.but b/doc/faq.but index 38531386..e2577bf4 100644 --- a/doc/faq.but +++ b/doc/faq.but @@ -1,4 +1,4 @@ -\versionid $Id: faq.but,v 1.22 2002/03/24 13:42:30 jacob Exp $ +\versionid $Id: faq.but,v 1.30 2002/07/09 11:34:10 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? -Not at present. OpenSSH and \cw{ssh.com} have totally different -formats for private key files, and neither one is particularly -pleasant, so PuTTY has its own. We do plan to write a converter at -some stage. +Version 0.52 doesn't, but in the latest development snapshots +PuTTYgen can load and save both OpenSSH and \cw{ssh.com} private key +files. \S{faq-ssh1}{Question} Does PuTTY support SSH v1? @@ -532,6 +531,36 @@ and you should report it (although it might be a bug in your SSH server instead); but it doesn't necessarily mean you've actually run out of memory. +\S{faq-outofmem2}{Question} When attempting a file transfer, either +PSCP or PSFTP says \q{Out of memory} and dies. + +This is almost always caused by your login scripts on the server +generating output. PSCP or PSFTP will receive that output when they +were expecting to see the start of a file transfer protocol, and +they will attempt to interpret the output as file-transfer protocol. +This will usually lead to an \q{out of memory} error for much the +same reasons as given in \k{faq-outofmem}. + +This is a setup problem in your account on your server, \e{not} a +PSCP/PSFTP bug. Your login scripts should \e{never} generate output +during non-interactive sessions; secure file transfer is not the +only form of remote access that will break if they do. + +On Unix, a simple fix is to ensure that all the parts of your login +script that might generate output are in \c{.profile} (if you use a +Bourne shell derivative) or \c{.login} (if you use a C shell). +Putting them in more general files such as \c{.bashrc} or \c{.cshrc} +is liable to lead to problems. + +\S{faq-psftp-slow} PSFTP transfers files much slower than PSCP. + +We believe this is because the SFTP and SSH2 protocols are less +efficient at bulk data transfer than SCP and SSH1, because every +block of data transferred requires an acknowledgment from the far +end. It would in theory be possible to queue several blocks of data +to get round this speed problem, but as yet we haven't done the +coding. If you really want this fixed, feel free to offer to help. + \S{faq-bce}{Question} When I run full-colour applications, I see areas of black space where colour ought to be. @@ -693,11 +722,13 @@ PuTTY to use SSH protocol 2 and the Blowfish cipher. This is not a PuTTY-specific problem; if you try to connect with another client you'll likely have similar problems. -Configurations known to be broken and symptoms: +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) +\b SSH 2 with 3DES (PuTTY says "Incorrect MAC received on packet") + \b SSH 1 with Blowfish (PuTTY says "Incorrect CRC received on packet") @@ -707,6 +738,21 @@ For more details and OpenSSH patches, see \W{http://bugzilla.mindrot.org/show_bug.cgi?id=138}{bug 138} in the OpenSSH BTS. +\e{Update:} As of OpenSSH 3.4p1 the problem with SSH 1 and Blowfish +remains. Apply the patch linked to from bug 138, or use another cipher +(e.g., 3DES) instead. + +\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 \S{faq-publicpc}{Question} Is it safe for me to download PuTTY and