Library libssh2

Provides a binding for the libssh2 library.

SSH2 is a complex protocol and libssh2 simplifies many tasks involved in interacting with ssh servers. This module provides bindings for some of the most commonly used libssh2 functions. You may wish to use the functionality in libssh2-utility instead, which wraps many of the functions here in an easier to use class, SSHConnection.

For performance reasons, the modules reuses the NSE's existing nsock socket pool.

Authors:

• Devin Bjelland
• Sergey Khegay

Copyright © Same as Nmap--See https://nmap.org/book/man-legal.html

Functions

channel_close (session, channel)

Gracefully closes open libssh2 channel

channel_eof (channel)

Checks if server has sent EOF on libssh2 channel

channel_exec (session, channel, cmd)

Executes command on libssh2 channel and returns output

channel_read (session, channel)

Reads data from stdin on libssh2 channel.

channel_read_stderr (session, channel)

Reads data from stderr on libssh2 channel.

channel_send_eof (session, channel)

Sends EOF on libssh2 channel. Note that the server may continue to send data until it sends its own EOF (which can be checked with channel_eof()

channel_write (session, channel, buffer)

Writes data to libssh2 channel. Not garenteed to write entire buffer.

hostkey_hash (session, hashtype)

Returns SHA1 or MD5 hostkey hash of session

open_channel (session)

Opens channel on authenticated ssh2 session and sets it to pseudo terminal mode.

publickey_canauth (session, username, publickeydata)

Checks to see if ssh server accepts public key for authentication as given user. This doesn't require the private key as it doesn't finish authenticating.

read_publickey (publickeyfile)

Read publickey from id_*.pub type key file

session_close (session)

Gracefully closes connected libssh2 session

session_open (host, port)

Creates libssh2 session and performs handshake

set_timeout (session, timeout)

Sets timeout of libssh2 session

userauth_list (session)

Returns list of authentication methods supported by the server

userauth_password (session, username, password)

Attempts to authenicate libssh2 session using provided credentials

userauth_publickey (session, username, privatekeyfile, passphrase, publickeyfile)

Attempts to authenticate libssh2 session using provided publickey

Functions

channel_close (session, channel)

Gracefully closes open libssh2 channel

Parameters

session

Authenticated libssh2 session

channel

Open libssh2 channel

channel_eof (channel)

Checks if server has sent EOF on libssh2 channel

Parameters

channel

Open libssh2 channel

Return value:

true/false depending on whether server has send EOF

channel_exec (session, channel, cmd)

Executes command on libssh2 channel and returns output

Parameters

session

Authenticated libssh2 session

channel

Open libssh2 channel

cmd

String containing command to execute

Return value:

String containing output from command

channel_read (session, channel)

Reads data from stdin on libssh2 channel.

Parameters

session

Authenticated libssh2 session

channel

Open libssh2 channel

Return value:

string containing data read from channel

channel_read_stderr (session, channel)

Reads data from stderr on libssh2 channel.

Parameters

session

Authenticated libssh2 session

channel

Open libssh2 channel

Return value:

string containing data read from channel

channel_send_eof (session, channel)

Sends EOF on libssh2 channel. Note that the server may continue to send data until it sends its own EOF (which can be checked with channel_eof()

Parameters

session

Authenticated libssh2 session

channel

Open libssh2 channel

channel_write (session, channel, buffer)

Writes data to libssh2 channel. Not garenteed to write entire buffer.

Parameters

session

Authenticated libssh2 session

channel

Open libssh2 channel

buffer

String containing data to be written

Return value:

Number of bytes written to channel

hostkey_hash (session, hashtype)

Returns SHA1 or MD5 hostkey hash of session

Parameters

session

Connected libssh2 session.

hashtype

(optional) "sha1" or "md5" (sha1 is default)

Return value:

hostkey hash of server

open_channel (session)

Opens channel on authenticated ssh2 session and sets it to pseudo terminal mode.

Parameters

session

Authenticated libssh2 session

Return value:

libssh2 channel

publickey_canauth (session, username, publickeydata)

Checks to see if ssh server accepts public key for authentication as given user. This doesn't require the private key as it doesn't finish authenticating.

Parameters

session

Connected libssh2 session

username

Username to authenicate as

publickeydata

String containing raw publickey blob

Return value:

true/false, depending on whether user can authenticate with given key

read_publickey (publickeyfile)

Read publickey from id_*.pub type key file

Parameters

publickeyfile

File containing publickey

Return value:

string containing raw key data

session_close (session)

Gracefully closes connected libssh2 session

Parameters

session

Connected libssh2 session

session_open (host, port)

Creates libssh2 session and performs handshake

Parameters

host

Host to connect to.

port

Port to connect to.

Return value:

session or nil on failure

set_timeout (session, timeout)

Sets timeout of libssh2 session

Parameters

session

Connected libssh2 session.

timeout

Timeout for session in milliseconds.

userauth_list (session)

Returns list of authentication methods supported by the server

Parameters

session

Connected libssh2 session.

Return value:

List of supported authentication methods/

userauth_password (session, username, password)

Attempts to authenicate libssh2 session using provided credentials

Parameters

session

 

username

Username to authenicate as.

password

Password to authenicate with.

Return value:

true/false, depending on success

userauth_publickey (session, username, privatekeyfile, passphrase, publickeyfile)

Attempts to authenticate libssh2 session using provided publickey

Parameters

session

Connected libssh2 session

username

Username to authenicate as

privatekeyfile

File containing privatekey

passphrase

Passphrase for privatekey

publickeyfile

File containing publickey. Not necessary if libssh2 is compiled against OpenSSL

Return value:

true/false, depending on success