1 SILC - Secure Internet Live Conferencing
2 ========================================
4 [NOTE: SILC is still in middle of development and this package is known
5 as Developer's Version which means that the package is in no means stable
6 or ready to be in production use. This package is for those who wants
7 to test SILC, find bugs and maybe contribute some time and code for the
8 SILC project. There is no guarantees that this package even compiles and
9 even if it compiles there is no guarantees that it would work, and even
10 if it works there is no guarantees that it would work correctly, and even
11 if it seems to work correctly it may be just plain luck.]
17 SILC (Secure Internet Live Conferencing) is a protocol which provides
18 secure conferencing services in the Internet over insecure channel.
19 SILC is IRC like softwarre although internally they are very different.
20 Biggest similiarity between SILC and IRC is that they both provide
21 conferencing services and that SILC has almost same commands as IRC. Other
22 than that they are nothing alike. Biggest differences are that SILC is
23 secure what IRC is not in any way. The network model is also entirely
24 different compared to IRC.
30 The development version is still preliminary version and requires some
31 work to get it working. You should, first of all, check the example
32 configuration files in ./doc/ directory. Change them according to your
38 ./silc -f <config file>
43 ./silcd -f <config file>
49 Following commands has been, at least partly, implemented:
52 /SERVER [<server>[:<port>]]
54 Connects to remote SILC server.
58 Changes/sets nickname. Note that in SILC there can be
59 multiple same nicknames. However, the logic on working
60 with multiple nicknams on user interface is pretty much
61 still missing. Also note that nicknames in SILC are
66 Joins to a channel. Channel names start with `#'
71 Leaves the channel. If /leave * is given the client
72 leaves the current channel.
76 Lists clients currently joined to the channel.
78 /MSG <nickname> <message>
80 Sends private message to remote client. Support for
81 handling multiple same nicknames with /MSG command is
84 /WHOIS <nickname>[@<server>] [<count>]
86 Gives a little information about a client. Support for
87 handling multiple same nicknames with this command is
92 Pings server. Only locally connected server may be
97 Quits session. Connection to remote server is closed.
101 Clears current screen.
107 Features to be included into the final release of SILC. [Note that the
108 current Developer's Version does not include all of these features, read
109 TODO file for more information.]
111 o Normal conferencing services such as private messages, channels,
112 channel messages, etc. All traffic is secured and authenticated.
114 o No unique nicknames. There can same nicknames in SILC without
115 collisions. SILC has unique Client ID's, Server ID's and Channel ID's
116 to assure that there are no collisions.
118 o Secure key exchange and authentication protocol. SILC Key Exchange
119 protocol provides key material used in the SILC sessions in secure
120 manner. The protocol is immune for example to man-in-the-middle
121 attacks. The SILC Authentication protocol provides strong
122 authentication. Authentication may be based on passphrase or public
123 key (RSA) authentication. For clients there is an option not to
124 use authentication when connecting to servers.
126 o All traffic is encrypted and authenticated using the best cryptographic
127 algorithms out there. Command messages, private messages and channel
128 messages are all protected by encryption. User can set private keys
129 for both private message and for channels so that even SILC servers do
130 not know the keys. Cipher keys are, by default, 128 bits in length and
131 public keys, by default, 1024 bits in length.
133 o Supports data compression with GZIP to improve performance.
135 o Supports SOCKS4 and SOCKS5 firewall traversal protocols.
137 o SIM (SILC Module) support. Support for loading of shared objects at
138 run-time that provides new and extended features to both SILC client
139 and server. These can provide extra ciphers and extra features to
142 o SILC client can be installed and used without root privileges.
144 o SILC client can be configured by system wide configuration files but
145 with user specific configuration files as well.
151 Even though SILC were just released to the public the idea and the protocol
152 itself is quite old. I got the idea about SILC in its current form in
153 the year 1996 and first lines of codes were written in early 1997. This
154 release is now third rewrite of the SILC. The very first version were
155 written in 1997 and it included SILC client and very very preliminary
156 SILC server. The server actually weren't usable but the client looked
157 pretty much the same as it does now. At that time the SILC also included
158 RSA implementation and 3DES implementation. The random number generator
159 that exists in this current release is actually based on the RNG written
160 in 1997. The RNG written in 1997, on the other hand, were based on
161 the SSH's random number generator. The RNG has been rewritten twice
162 since the first version.
164 I stopped writing the SILC later in 1997 when I got busy at school and
165 in work. The pause lasted several months. The development resumed in
166 1998 when my friend (Juha Räsänen) and I implemented ElGamal algorithm.
167 I rewrote some other parts as well. However, for the same reasons as
168 previously the development stopped again. I resumed the development
169 later in 1998 by doing rewrite of the SILC in C++. This was obviously
170 a mistake but at that time it seemed like a good idea. Again, in the
171 winter 1999 I got very busy writing my thesis and was forced to stop the
172 development again. I also, started a new job in the spring.
174 Later, in 1999, I decided that this time I'm going to make it the right
175 way. C++ was obviously a bad choice so I decided to fall back to plain
176 C language. I also decided to do complete rewrite and started doing
177 more thorough planning of what the SILC actually should include. I also
178 decided that this time it is going to kill me before I stop the
179 development. I started writing SILC in the weekends and actually
180 everytime I had some spare time. I also started a new job but I didn't
181 let that get to my way. The result of this development effort is the
182 release now in public.
184 I've learned a lot by doing the SILC. I guess, when I started it I wasn't
185 that good of a C programmer. That alone was a reason why SILC hasn't
186 seen the day of light before now. My programming style has also changed
187 dramatically during these years. Actually, it has changed couple times
188 since this last rewrite as well. However, the code style of current SILC
189 release is quite consistent (actually the coding style SILC has been
190 written now I've learned in my current job).
192 There is probably over 85% of new code in this third rewrite. Rest has
193 just been copied from the old versions and only minor changes has been
194 made (like changed function names and overall coding style). I've
195 preserved the dates of the old files (dating back to 1997) that has
196 existed in some forms in the old versions. There is a lot of new code but
197 already I see a lot that needs rewriting. The development continues.
203 Feedback and comments are welcome. You can reach me in the following
206 [Note that generally bug reports should not be sent just yet as the
207 Developer's Version is full of them and the bug hunt has not even started
210 Pekka Riikonen <priikone@poseidon.pspt.fi>