3 SILC Specification ............................................ 7
3.1 Client .................................................... 7
3.1.1 Client ID ........................................... 8
- 3.2 Server .................................................... 8
+ 3.2 Server .................................................... 9
3.2.1 Server's Local ID List .............................. 9
3.2.2 Server ID ........................................... 10
- 3.2.3 SILC Server Ports ................................... 10
+ 3.2.3 SILC Server Ports ................................... 11
3.3 Router .................................................... 11
3.3.1 Router's Local ID List .............................. 11
3.3.2 Router's Global ID List ............................. 12
- 3.3.3 Router's Server ID .................................. 12
- 3.4 Channels .................................................. 12
- 3.4.1 Channel ID .......................................... 13
+ 3.3.3 Router's Server ID .................................. 13
+ 3.4 Channels .................................................. 13
+ 3.4.1 Channel ID .......................................... 14
3.5 Operators ................................................. 14
- 3.6 SILC Commands ............................................. 14
+ 3.6 SILC Commands ............................................. 15
3.7 SILC Packets .............................................. 15
- 3.8 Packet Encryption ......................................... 15
+ 3.8 Packet Encryption ......................................... 16
3.8.1 Determination of the Source and the Destination ..... 16
- 3.8.2 Client To Client .................................... 16
- 3.8.3 Client To Channel ................................... 17
- 3.8.4 Server To Server .................................... 18
- 3.9 Key Exchange And Authentication ........................... 18
+ 3.8.2 Client To Client .................................... 17
+ 3.8.3 Client To Channel ................................... 18
+ 3.8.4 Server To Server .................................... 19
+ 3.9 Key Exchange And Authentication ........................... 19
3.10 Algorithms ............................................... 19
3.10.1 Ciphers ............................................ 19
3.10.2 Public Key Algorithms .............................. 20
3.10.3 MAC Algorithms ..................................... 20
- 3.10.4 Compression Algorithms ............................. 20
+ 3.10.4 Compression Algorithms ............................. 21
3.11 SILC Public Key .......................................... 21
-4 SILC Procedures ............................................... 23
- 4.1 Creating Client Connection ................................ 23
- 4.2 Creating Server Connection ................................ 24
- 4.3 Joining to a Channel ...................................... 25
- 4.4 Channel Key Generation .................................... 26
+4 SILC Procedures ............................................... 24
+ 4.1 Creating Client Connection ................................ 24
+ 4.2 Creating Server Connection ................................ 25
+ 4.3 Joining to a Channel ...................................... 26
+ 4.4 Channel Key Generation .................................... 27
4.5 Private Message Sending and Reception ..................... 27
- 4.6 Private Message Key Generation ............................ 27
- 4.7 Channel Message Sending and Reception ..................... 28
- 4.8 Session Key Regeneration .................................. 28
+ 4.6 Private Message Key Generation ............................ 28
+ 4.7 Channel Message Sending and Reception ..................... 29
+ 4.8 Session Key Regeneration .................................. 29
4.9 Command Sending and Reception ............................. 29
-5 SILC Commands ................................................. 29
- 5.1 SILC Commands Syntax ...................................... 29
- 5.2 SILC Commands List ........................................ 31
- 5.3 SILC Command Status Types ................................. 54
- 5.3.1 SILC Command Status Payload ......................... 54
+5 SILC Commands ................................................. 30
+ 5.1 SILC Commands Syntax ...................................... 30
+ 5.2 SILC Commands List ........................................ 32
+ 5.3 SILC Command Status Types ................................. 53
+ 5.3.1 SILC Command Status Payload ......................... 53
5.3.2 SILC Command Status List ............................ 54
-6 Security Considerations ....................................... 58
+6 Security Considerations ....................................... 59
7 References .................................................... 59
8 Author's Address .............................................. 60
This document describes a Secure Internet Live Conferencing (SILC)
protocol which provides secure conferencing services over insecure
network channel. SILC is IRC [IRC] like protocol, however, it is
-not equivalent to IRC and does not support IRC. Strong cryptographic
-methods are used to protect SILC packets inside SILC network. Two
-other Internet Drafts relates very closely to this memo; SILC Packet
-Protocol [SILC2] and SILC Key Exchange and Authentication Protocols
-[SILC3].
+not equivalent to IRC and does not support IRC.
+
+Strong cryptographic methods are used to protect SILC packets inside
+SILC network. Two other Internet Drafts relates very closely to this
+memo; SILC Packet Protocol [SILC2] and SILC Key Exchange and
+Authentication Protocols [SILC3].
The protocol uses extensively packets as conferencing protocol
requires message and command sending. The SILC Packet Protocol is
SILC network is a cellular network as opposed to tree style network
topology. The rationale for this is to have servers that can perform
specific kind of tasks what other servers cannot perform. This leads
-to two kinds of servers; normal SILC servers and SILC routers.
+to two kinds of servers; normal SILC servers and SILC routers.
+
A difference between normal server and router server is that routers
knows everything about everything in the network. They also do the
actual routing of the messages to the correct receiver. Normal servers
This, on the other hand, leads to cellular like network, where routers
are in the centrum on the cell and servers are connected to the router.
+
Following diagram represents SILC network topology.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
.in 8
.nf
---- ---- ---- ---- ---- ----
are delivered from one router to the other router.
-
-
-
.ti 0
2.4 Channel Communication
Normal server also keeps information about locally created channels and
their Channel ID's.
+
+
+
+
+
+
+
Hence, local list for normal server includes:
.in 6
o Sending key
o Receiving key
-
-
channel list - All channels in server
o Channel name
o Channel ID
since these are not needed by the router. Router keeps only information
that it needs.
+
+
+
+
Hence, local list for router includes:
.in 6
o Server ID
o Router's Server ID
+
client list - All clients in SILC
o Client ID
SILC packets.
+
+
.ti 0
3.8 Packet Encryption
definition of how it must be done. SILC has a mandatory algorithm that
must be supported in order to be compliant with this protocol.
+
+
+
+
+
Following ciphers are defined in SILC protocol:
.in 6
same name format as above.
-
-
-
-
.ti 0
3.10.2 Public Key Algorithms
(MAC) of the packet data. See [SILC2] for details how to compute the
MAC.
+
+
+
+
Following MAC algorithms are defined in SILC protocol:
.in 6
The format of the SILC Public Key is as follows:
+
+
+
+
+
.in 5
.nf
1 2 3
normal session keys established by SILC Key Exchange protocol.
+
+
.ti 0
4.7 Channel Message Sending and Reception
command replies. The number of argument is marked in parentheses
before the actual argument.
+
+
+
+
.in 6
Example: Arguments: (1) <nickname> (2) <username@host>
.in 3
<message> argument, regardles of the ordering of the arguments in
the Command Payload.
-
-
-
-
Reply messages to the command:
Max Arguments: 4
argument for all command replies and for this reason it is not
described in the command reply descriptions.
+
+
Status messages:
SILC_STATUS_OK
SILC_STATUS_ERR_NO_SUCH_SERVER
-
-
-
-
-
7 SILC_COMMAND_TOPIC
Max Arguments: 2
SILC_STATUS_ERR_NO_CLIENT_ID
+
+
+
11 SILC_COMMAND_INFO
Max Arguments: 1
SILC_STATUS_ERR_NO_SUCH_SERVER
-
-
-
-
12 SILC_COMMAND_CONNECT
Max Arguments: 2
This command replies only with Status Payload.
+
+
Status messages:
SILC_STATUS_OK
SILC_STATUS_ERR_AUTH_FAILED
-
-
-
-
-
15 SILC_COMMAND_JOIN
Max Arguments: 3
SILC_STATUS_ERR_NO_SUCH_SERVER
-
-
-
-
17 SILC_COMMAND_UMODE
Max Arguments: 2
SILC_STATUS_ERR_NO_CLIENT_ID
+
+
19 SILC_COMMAND_KICK
Max Arguments: 3
This command replies only with Status Payload.
+
+
Status messages:
SILC_STATUS_OK
Reply messages to the command:
+
+
Max Arguments: 1
Arguments: (1) <Status Payload>
"Unknown command". Command sent to server is unknown by the
server.
-
-
16 SILC_STATUS_ERR_WILDCARDS
"Wildcards cannot be used". Wildcards were provided but they
"You are banned from this server". The client tried to register
on server that has explicitly denied this host to connect.
+
+
31 SILC_STATUS_ERR_BAD_PASSWORD
"Cannot join channel. Incorrect password". Password provided for
"Cannot join channel. You have been banned". The client has
been banned from the channel.
-
-
35 SILC_STATUS_ERR_UNKNOWN_MODE
"Unknown mode". Mode provided by the client were unknown to
-
-
-
-
.ti 0
8 Author's Address
projects / silc.git / commitdiff