paramiko 1.0 "jigglypuff" release, 6 nov 2004 Copyright (c) 2003-2004 Robey Pointer http://www.lag.net/~robey/paramiko/ *** WHAT "paramiko" is a combination of the esperanto words for "paranoid" and "friend". it's a module for python 2.2+ that implements the SSH2 protocol for secure (encrypted and authenticated) connections to remote machines. unlike SSL (aka TLS), SSH2 protocol does not require heirarchical certificates signed by a powerful central authority. you may know SSH2 as the protocol that replaced telnet and rsh for secure access to remote shells, but the protocol also includes the ability to open arbitrary channels to remote services across the encrypted tunnel (this is how sftp works, for example). it is written entirely in python (no C or platform-dependent code) and is released under the GNU LGPL (lesser GPL). the package and its API is fairly well documented in the "doc/" folder that should have come with this archive. *** REQUIREMENTS python 2.3 (python 2.2 is also supported, but not recommended) pycrypto 1.9+ (2.0 works too) pycrypto compiled for Win32 can be downloaded from the HashTar homepage: http://nitace.bsd.uchicago.edu:8080/hashtar you can also build it yourself using the free MinGW tools and this command line (thanks to Roger Binns for the info): python setup.py build --compiler=mingw32 bdist_wininst *** PORTABILITY i code and test this library on Linux and MacOS X. for that reason, i'm pretty sure that it works for all posix platforms, including MacOS. i also think it will work on Windows, though i've never tested it there. if you run into Windows problems, send me a patch: portability is important to me. the Channel object supports a "fileno()" call so that it can be passed into select or poll, for polling on posix. once you call "fileno()" on a Channel, it changes behavior in some fundamental ways, and these ways require posix. so don't call "fileno()" on a Channel on Windows. this is detailed in the documentation for the "fileno" method. python 2.2 may work, thanks to some patches from Roger Binns. things to watch out for: * sockets in 2.2 don't support timeouts, so the 'select' module is imported to do polling. this may not work on windows. (works fine on osx.) * logging is mostly stubbed out. it works just enough to let paramiko create log files for debugging, if you want them. to get real logging, you can backport python 2.3's logging package. Roger has done that already: http://sourceforge.net/project/showfiles.php?group_id=75211&package_id=113804 you really should upgrade to python 2.3. laziness is no excuse! :) some python distributions don't include the utf-8 string encodings, for reasons of space (misdirected as that is). if your distribution is missing encodings, you'll see an error like this: LookupError: no codec search functions registered: can't find encoding this means you need to copy string encodings over from a working system. (it probably only happens on embedded systems, not normal python installls.) Valeriy Pogrebitskiy says the best place to look is '.../lib/python*/encodings/__init__.py'. *** DEMO several demo scripts come with paramiko to demonstrate how to use it. probably the simplest demo of all is this: import paramiko, base64 key = paramiko.RSAKey(data=base64.decodestring('AAA...')) t = paramiko.Transport('ssh.example.com') t.connect(username='strongbad', password='thecheat', hostkey=key) chan = t.open_session() chan.exec_command('ls') for line in chan.makefile('r+'): print '... ' + line.strip('\n') chan.close() t.close() ...which prints out the results of executing 'ls' on a remote server. (the host key 'AAA...' should of course be replaced by the actual base64 encoding of the host key. if you skip host key verification, the connection is not secure!) the following example scripts get progressively more detailed: demo_windows.py executes 'ls' on any remote server, loading the host key from your openssh key file. (this script works on windows because it avoids using terminal i/o or the 'select' module.) it also creates a logfile 'demo_windows.log'. demo_simple.py calls invoke_shell() and emulates a terminal/tty through which you can execute commands interactively on a remote server. think of it as a poor man's ssh command-line client. (works only on posix [unix or macosx].) demo.py same as demo_simple.py, but allows you to authenticiate using a private key, and uses the long form of some of the API calls. (posix only.) forward.py command-line script to set up port-forwarding across an ssh transport. (requires python 2.3 and posix.) demo_server.py an ssh server that listens on port 2200 and accepts a login for 'robey' (password 'foo'), and pretends to be a BBS. meant to be a very simple demo of writing an ssh server. (should work on all platforms.) *** USE the demo scripts are probably the best example of how to use this package. there is also a lot of documentation, generated with epydoc, in the doc/ folder. point your browser there. seriously, do it. mad props to epydoc, which actually motivated me to write more documentation than i ever would have before. there are also unit tests here: $ python ./test.py which will verify that some of the core components are working correctly. not much is tested yet, but it's a start. the tests for SFTP are probably the best and easiest examples of how to use the SFTP class. *** WHAT'S NEW highlights of what's new in each release: v1.0 JIGGLYPUFF * fixed bug that broke server-mode authentication by private key * fixed bug where closing a Channel could end up killing the entire Transport * actually include demo_windows.py this time (oops!) * fixed recently-introduced bug in group-exchange key negotiation that would generate the wrong hash (and therefore fail the initial handshake) * server-mode subsystem handler is a bit more flexible v0.9 IVYSAUR * new ServerInterface class for implementing server policy, so it's no longer necessary to subclass Transport or Channel -- server code will need to be updated to follow this new API! (see demo_server.py) * some bugfixes for re-keying an active session * Transport.get_security_options() allows fine-tuned control over the crypto negotiation on a new session * Transport.connect() takes a single hostkey object now instead of two string parameters * the Channel request methods (like 'exec_command') now return True on success or False on failure * added a mechanism for providing subsystems in server mode (and a new class to be subclassed: SubsystemHandler) * renamed SFTP -> SFTPClient (but left an alias for existing code) * added SFTPClient.normalize() to resolve paths on the server * fleshed out the API a bit more for SFTPClient and private keys * a bunch of new unit tests! v0.9 HORSEA * fixed a lockup that could happen if the channel was closed while the send window was full * better checking of maximum packet sizes * better line buffering for file objects * now chops sftp requests into smaller packets for some older servers * more sftp unit tests v0.9 GYARADOS * Transport.open_channel() -- supports local & remote port forwarding now * now imports UTF-8 encodings explicitly as a hint to "freeze" utilities * no longer rejects older SFTP servers * default packet size bumped to 8kB * fixed deadlock in closing a channel * Transport.connect() -- fixed bug where it would always fail when given a host key to verify v0.9 FEAROW * Transport.send_ignore() -- send random ignored bytes * RSAKey/DSSKey added from_private_key_file() as a factory constructor; write_private_key_file() & generate() to create and save ssh2 keys; get_base64() to retrieve the exported public key * Transport added global_request() [client] and check_global_request() [server] * Transport.get_remove_server_key() now returns a PKey object instead of a tuple of strings * Transport.get_username() -- return the username you auth'd as [client] * Transport.set_keepalive() -- makes paramiko send periodic junk packets to the remote host, to keep the session active * python 2.2 support (thanks to Roger Binns) * misc. bug fixes *** MISSING LINKS * ctr forms of ciphers are missing (blowfish-ctr, aes128-ctr, aes256-ctr) * multi-part auth not supported (ie, need username AND pk) * server mode needs better documentation * sftp server mode * figure out if there's a way to put stdout/stderr on different channels? * add method to block until a channel's "exit-status" is set * if password auth is forbidden (only key auth allowed), error isn't very informative -- improve that.