manpage(SILC) (1) (December 7 2002) (silc-client) (silc-client)


manpagename(silc) (client for SILC, a secure and flexible conferencing network)


manpagesynopsis()
bf(silc) bf([) -S em(file) | -d | -C | -c em(host) | -w em(pass) | 
-p em(port) | -! | -n em(nick) | -h em(host) | -v | -? bf(])


manpagedescription()
SILC (Secure Internet Live Conferencing) is a secure conferencing network.
bf(Silc) is the SILC client which is used to connect to SILC server and
the SILC network.  The silc client resembles IRC clients to make the
using easier for new users.

bf(Silc) supports sending of practically any kind of messages in addition
of normal text messages in the SILC network.  This includes multimedia
messages like images, video and audio stream.  The session to SILC server
is secured with session key, channel messages are protected with channel
key and private messages with session keys.  It is also possible to use
private channel keys and private message keys in addition to server
generated keys.  It is also possible to digitally sign all messages.

bf(Silc) supports em(passphrase) authentication and public key authentication
based on em(digital signatures), when connecting to SILC server.  bf(Silc)
also supports key exchange (key agreement) between other bf(Silc) users in
the SILC network to negotiate secret key material.  This key material then
can be used to secure for example private messages.  It is also possible to
exchange public keys and certificates in the SILC network between clients
and servers.

The bf(silc) also supports em(detaching) from the SILC network by closing
the connection to the server but without quitting from the network.  Next
time the bf(silc) connects to the server it em(resumes) the session in the
SILC network.  During the detaching the user remains in the network and other
users may query the user information and see that user is in network but
currently detached.  Messages sent to user while being detached are
dropped by the server.  When resuming is over the user has automatically
same nickname than before detaching and remains on all channels, and it
seems like user never left the network.

The bf(silc) also supports creation of em(friends) list, which is kind of
a buddy list familiar from IM (Instant Messaging) clients.  By using the
bf(WHOIS) SILC command with em(-details) option it is possible to fetch the
user's information such as their public keys and certificates, business
card, pictures, and other information and save them to the friends list.
The friends list is located at bf(~/.silc/friends/) directory.

The SILC public key and private key pair is used to authenticate the user
to the SILC server when connecting a server.  This key pair is created
automatically when the bf(silc) is run for the first time.  It can also
be created with bf(-C) option.

When connecting for the first time to SILC server, user will be asked to
accept the server's public key.  When key is accepted the bf(silc) saves
the public key for future into bf(~/.silc/serverkeys/) directory.  The
next time user connects to same server the public key is verified against
the saved public key.  The purpose of this public key saving is to avoid
man-in-the-middle attacks which could be possible if the key would have
to be verified every time user connects to the server.

manpageoptions()
bf(-c) em(host)      Connect to given host

bf(-p) em(port)      Connect to em(port)

bf(-C)           Create new public key pair

bf(-P)           Change the passphrase of the private key file

bf(-S) em(keyfile)   Display the contents of given SILC public key from file

bf(-n) em(nick)      Specify what nick to use

bf(-h) em(host)      Give em(host) as your hostname

bf(-w) em(pass)      Use em(pass) as password for connection

bf(-d) em(string)    Enable debugging

bf(-v)           Display client version

bf(-!)           Do not autoconnect

bf(-?)           Display client help message


manpagesection(LONG OPTIONS)

bf(--connect)=em(SERVER)     Same as bf(-c).

bf(--port)=em(PORT)          Same as bf(-p).

bf(--home)=em(PATH)          Client home dir (em(~/.silc)).

bf(--config)=em(PATH)        Configuration file location (em(~/.silc/silc.conf)).

bf(--list-ciphers)       List supported ciphers.

bf(--list-hash-funcs)    List supported hash functions.

bf(--list-hmacs)         List supported HMACs.

bf(--list-pkcs)          List supported PKCSs.

bf(--create-key-pair)    Same as bf(-C).

bf(--passphrase-change)  Same as bf(-P).

bf(--nick)=em(NICK)          Same as bf(-n).

bf(--hostname)=em(HOST)      Same as bf(-h).

bf(--password)=em(PASS)      Same as bf(-w).

bf(--debug)=em(STRING)       Same as bf(-d), limit to messages *em(STRING)*.

bf(--dummy)              Use dummy terminal mode.

bf(--version)            Same as bf(-v).

bf(--noconnect)          Same as bf(-!).

bf(--help)               Same as bf(-?).

bf(--usage)              Display very brief usage summary.


manpagesection(KEY GENERATION)
When generating key pair(s) for silc (bf(-C)), the following extra
switches apply:

bf(--pkcs)=em(PKCS)       Set the public key algorithm of key pair.  For example bf(rsa).

bf(--bits)=em(VALUE)       Set the length of public key pair, in bits.


manpagesection(CONFIGURATION FILE)
The bf(silc) configuration file is bf(~/.silc/silc.conf) and can be used
to configure the behaviour of the client.  The configuration file format
is equivalent to Irssi IRC client's configuration file.  See the 
documentation for the configuration file at bf(http://irssi.org).

There are a few bf(silc) configuration settings in em(silc.conf) which
can be configured in em(settings) section under em("server") block.
They can be set also with the bf(/SET) command in the bf(silc) client.

bf(crypto_default_cipher)
quote(The default cipher to use to secure the session to the server.
Values can be for example bf(aes-256-cbc), bf(aes-192-cbc), bf(aes-128-cbc),
bf(twofish-256-cbc), bf(twofish-192-cbc), bf(twofish-128-cbc).)

bf(crypto_default_hash)
quote(The default hash function to use in session with the server. Values
can be bf(sha1) or bf(md5).)

bf(crypto_default_hmac)
quote(The default HMAC to be use in session with the server.  Value can
be bf(hmac-sha1-96), bf(hmac-md5-96), bf(hmac-sha1) or bf(hmac-md5).)


manpagefiles()
bf(~/.silc/silc.conf)
quote(Client's configuration file)

bf(~/.silc/public_key.pub)
quote(The SILC public key of the user)

bf(~/.silc/private_key.pub)
quote(The SILC private key of the user)

bf(~/.silc/clientkeys/)
quote(The directory holding the public keys of other users the user has
accepted and trusted in the SILC network.  The public keys can be received
with bf(GETKEY) SILC command or during key agreement between two users.)

bf(~/.silc/serverkeys/)
quote(The directory holding the public keys of servers the user has accepted
and trusted when connecting to a server.)

bf(~/.silc/friends/)
quote(The directory holding the information of em(friends) that user has.
User can create a friend list with bf(WHOIS -details) SILC command.  This
directory holds the friends' public keys, business cards, pictures, and
other information.)


manpageseealso()
bf(silcd(8)) bf(silcd.conf(5))


manpagesection(NETWORK RESOURCES)
Homepage: bf(http://silcnet.org)

SILC Client is based on Irssi IRC client: bf(http://irssi.org)

User's guide: bf(http://silcnet.org/docs/)


manpageauthor()
SILC is designed and written by Pekka Riikonen <priikone@iki.fi> and rest
of the SILC Project.

This manpage was written by Mika 'Bostik' Boström <bostik@lut.fi>

See bf(CREDITS) for full list of contributors.


