X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/8452efbc975bdfd2a9891cc1f82f158dc0c7e073..055817455466c8eb60392f30bb7c689763962e17:/doc/pscp.but diff --git a/doc/pscp.but b/doc/pscp.but index 73a18895..4485b9b1 100644 --- a/doc/pscp.but +++ b/doc/pscp.but @@ -1,15 +1,16 @@ -\versionid $Id: pscp.but,v 1.11 2001/06/28 13:36:14 owen Exp $ +\define{versionidpscp} \versionid $Id$ \#FIXME: Need examples \C{pscp} Using PSCP to transfer files securely -\# Explain PSCP: the command line, the modes of use (local->remote -\# and remote->local, recursive, wildcards). - \i{PSCP}, the PuTTY Secure Copy client, is a tool for transferring files securely between computers using an SSH connection. +If you have an SSH 2 server, you might prefer PSFTP (see \k{psftp}) +for interactive use. PSFTP does not in general work with SSH 1 +servers, however. + \H{pscp-starting} Starting PSCP PSCP is a command line application. This means that you cannot just @@ -40,17 +41,28 @@ use PSCP: \c Z:\owendadmin>pscp \c PuTTY Secure Copy client -\c Release 0.50 +\c Release 0.XX \c Usage: pscp [options] [user@]host:source target -\c pscp [options] source [source...] [user@]host:target -\c pscp [options] -ls user@host:filespec +\c pscp [options] source [source...] [user@]host:target +\c pscp [options] -ls [user@]host:filespec \c Options: \c -p preserve file attributes \c -q quiet, don't show statistics \c -r copy directories recursively \c -v show verbose messages +\c -load sessname Load settings from saved session \c -P port connect to specified port +\c -l user connect with specified username \c -pw passw login with specified password +\c -1 -2 force use of particular SSH protocol version +\c -4 -6 force use of IPv4 or IPv6 +\c -C enable compression +\c -i key private key file for authentication +\c -batch disable all interactive prompts +\c -unsafe allow server-side wildcards (DANGEROUS) +\c -V print version information +\c -sftp force use of SFTP protocol +\c -scp force use of SCP protocol (PSCP's interface is much like the Unix \c{scp} command, if you're familiar with that.) @@ -70,11 +82,53 @@ To send (a) file(s) to a remote server: \c pscp [options] source [source...] [user@]host:target -So to copy the local file \c{c:\\documents\\csh-whynot.txt} to the -server \c{example.com} as user \c{fred} to the file -\c{/tmp/csh-whynot} you would type: - -\c pscp c:\documents\csh-whynot.txt fred@example.com:/tmp/csh-whynot +So to copy the local file \c{c:\\documents\\foo.txt} to the server +\c{example.com} as user \c{fred} to the file \c{/tmp/foo} you would +type: + +\c pscp c:\documents\foo.txt fred@example.com:/tmp/foo + +You can use wildcards to transfer multiple files in either +direction, like this: + +\c pscp c:\documents\*.doc fred@example.com:docfiles +\c pscp fred@example.com:source/*.c c:\source + +However, in the second case (using a wildcard for multiple remote +files) you may see a warning saying something like \q{warning: +remote host tried to write to a file called 'terminal.c' when we +requested a file called '*.c'. If this is a wildcard, consider +upgrading to SSH 2 or using the '-unsafe' option. Renaming of this +file has been disallowed}. + +This is due to a fundamental insecurity in the old-style SCP +protocol: the client sends the wildcard string (\c{*.c}) to the +server, and the server sends back a sequence of file names that +match the wildcard pattern. However, there is nothing to stop the +server sending back a \e{different} pattern and writing over one of +your other files: if you request \c{*.c}, the server might send back +the file name \c{AUTOEXEC.BAT} and install a virus for you. Since +the wildcard matching rules are decided by the server, the client +cannot reliably verify that the filenames sent back match the +pattern. + +PSCP will attempt to use the newer SFTP protocol (part of SSH 2) +where possible, which does not suffer from this security flaw. If +you are talking to an SSH 2 server which supports SFTP, you will +never see this warning. (You can force use of the SFTP protocol, +if available, with \c{-sftp} - see \k{pscp-usage-options-backend}.) + +If you really need to use a server-side wildcard with an SSH 1 +server, you can use the \c{-unsafe} command line option with PSCP: + +\c pscp -unsafe fred@example.com:source/*.c c:\source + +This will suppress the warning message and the file transfer will +happen. However, you should be aware that by using this option you +are giving the server the ability to write to \e{any} file in the +target directory, so you should only use this option if you trust +the server administrator not to be malicious (and not to let the +server machine be cracked by malicious people). \S2{pscp-usage-basics-user} \c{user} @@ -121,6 +175,14 @@ directory on the remote server. \S{pscp-usage-options} Options +PSCP accepts all the general command line options supported by the +PuTTY tools, except the ones which make no sense in a file transfer +utility. See \k{using-general-opts} for a description of these +options. (The ones not supported by PSCP are clearly marked.) + +PSCP also supports some of its own options. The following sections +describe PSCP's specific command-line options. + These are the command line options that PSCP accepts. \S2{pscp-usage-options-p}\c{-p} preserve file attributes @@ -134,7 +196,7 @@ timestamp on copied files. By default, PSCP displays a meter displaying the progress of the current transfer: -\c mibs.tar | 168 kB | 84.0 kB/s | ETA: 00:00:13 | 13% +\c mibs.tar | 168 kB | 84.0 kB/s | ETA: 00:00:13 | 13% The fields in this display are (from left to right), filename, size (in kilobytes) of file transferred so far, estimate of how fast the @@ -151,59 +213,80 @@ PSCP to descend into any directories you specify, and to copy them and their contents. This allows you to use PSCP to transfer whole directory structures between machines. -\S2{pscp-usage-options-v}\c{-v} show \i{verbose} messages +\S2{pscp-usage-options-batch}\c{-batch} avoid interactive prompts + +If you use the \c{-batch} option, PSCP will never give an +interactive prompt while establishing the connection. If the +server's host key is invalid, for example (see \k{gs-hostkey}), then +the connection will simply be abandoned instead of asking you what +to do next. -The \c{-v} option to PSCP makes it print extra information about the -file transfer. For example: +This may help PSCP's behaviour when it is used in automated +scripts: using \c{-batch}, if something goes wrong at connection +time, the batch job will fail rather than hang. -\c Logging in as "fred". -\c fred@example.com's password: -\c Sending command: scp -v -f mibs.tar -\c Connected to example.com -\c Sending file modes: C0644 1320960 mibs.tar -\c mibs.tar | 1290 kB | 67.9 kB/s | ETA: 00:00:00 | 100% -\c Remote exit status 0 -\c Closing connection +\S2{pscp-usage-options-backend}\c{-sftp}, \c{-scp} force use of +particular protocol -This information may be useful for debugging problems with PSCP. +As mentioned in \k{pscp-usage-basics}, there are two different file +transfer protocols in use with SSH. Despite its name, PSCP (like many +other ostensible \cw{scp} clients) can use either of these protocols. -\S2{pscp-usage-options-P}\c{-P port} connect to specified \i{port} +The older SCP protocol does not have a written specification and +leaves a lot of detail to the server platform. Wildcards are expanded +on the server. The simple design means that any wildcard specification +supported by the server platform (such as brace expansion) can be +used, but also leads to interoperability issues such as with filename +quoting (for instance, where filenames contain spaces), and also the +security issue described in \k{pscp-usage-basics}. -If the \c{host} you specify is a saved session, PSCP uses any port -number specified in that saved session. If not, PSCP uses the default -SSH port, 22. The \c{-P} option allows you specify the port number to -connect to for PSCP's SSH connection. +The newer SFTP protocol, which is usually associated with SSH 2 +servers, is specified in a more platform independent way, and leaves +issues such as wildcard syntax up to the client. (PuTTY's SFTP +wildcard syntax is described in \k{psftp-wildcards}.) This makes it +more consistent across platforms, more suitable for scripting and +automation, and avoids security issues with wildcard matching. -\S2{pscp-usage-options-pw}\c{-pw passw} login with specified \i{password} +Normally PSCP will attempt to use the SFTP protocol, and only fall +back to the SCP protocol if SFTP is not available on the server. -If a password is required to connect to the \c{host}, PSCP will -interactively prompt you for it. However, this may not always be -appropriate. If you are running PSCP as part of some automated job, -it will not be possible to enter a password by hand. The \c{-pw} -option to PSCP lets you specify the password to use on the command -line. +The \c{-scp} option forces PSCP to use the SCP protocol or quit. -Since specifying passwords in scripts is a bad idea for security -reasons, you might want instead to consider using public-key -authentication; see \k{pscp-pubkey}. +The \c{-sftp} option forces PSCP to use the SFTP protocol or quit. +When this option is specified, PSCP looks harder for an SFTP server, +which may allow use of SFTP with SSH 1 depending on server setup. + +\S{pscp-retval} Return value + +PSCP returns an \cw{ERRORLEVEL} of zero (success) only if the files +were correctly transferred. You can test for this in a batch file, +using code such as this: + +\c pscp file*.* user@hostname: +\c if errorlevel 1 echo There was an error \S{pscp-pubkey} Using public key authentication with PSCP Like PuTTY, PSCP can authenticate using a public key instead of a -password. There are two ways you can do this. +password. There are three ways you can do this. Firstly, PSCP can use PuTTY saved sessions in place of hostnames (see \k{pscp-usage-basics-host}). So you would do this: \b Run PuTTY, and create a PuTTY saved session (see \k{config-saving}) which specifies your private key file (see -\k{config-auth}). You will probably also want to specify a username -to log in as (see \k{config-username}). +\k{config-ssh-privkey}). You will probably also want to specify a +username to log in as (see \k{config-username}). \b In PSCP, you can now use the name of the session instead of a -hostname: \c{pscp sessionname:file localfile}. +hostname: type \c{pscp sessionname:file localfile}, where +\c{sessionname} is replaced by the name of your saved session. -Secondly, PSCP will attempt to authenticate using Pageant if Pageant +Secondly, you can supply the name of a private key file on the command +line, with the \c{-i} option. See \k{using-cmdline-identity} for more +information. + +Thirdly, PSCP will attempt to authenticate using Pageant if Pageant is running (see \k{pageant}). So you would do this: \b Ensure Pageant is running, and has your private key stored in it. @@ -213,9 +296,3 @@ automatically detect Pageant and try to use the keys within it. For more general information on public-key authentication, see \k{pubkey}. - -\H{pscp-ixplorer} \i{Secure iXplorer} - -Lars Gunnarson has written a graphical interface for PSCP. You can -get it from his web site, at -\W{http://www.i-tree.org/}{www.i-tree.org}.