--- name: "silcd.conf" section: "5" platform: "linux" package: "silcd" version: "1.1.18-1" release: "Debian 6.0 (Squeeze)" platforms: ["linux"] url: "https://new.carta.tech/silcd.conf" --- # silcd.conf(5) format of configuration file for silcd ## NAME silcd.conf - format of configuration file for silcd ## CONFIGURATION FILE **Silcd** reads its configuration from /etc/silc/silcd.conf (or the file specified with **-f**). The file contains sections, subsections and key-value pairs. Each section or subsection is bound with a starting *{* and ending *}*. Keys and values are of the format '*KEY*=*VALUE*;'. All statements as well as sections must be terminated with a ';'. Mandatory section in configuration file is *ServerInfo*. Other sections are optional but recommended. If *General* section is defined it must be defined before the *ConnectionParams* section. On the other hand, the *ConnectionParams* section must be defined before *Client*, *ServerConnection* and/or *RouterConnection* sections. Other sections can be in a free order in the configuration file. ## SECTION: General *General* section contains global settings for the silcd. **dynamic\_server** Dynamic router connections. If this is set for normal SILC server the connection to primary router is not created untill it is actually needed. Giving for example */WHOIS foobar@silcnet.org* would then create connection to the primary router to resolve user foobar. On the other hand giving */WHOIS foobar* would try to search the user foobar locally, without creating the connection. Note that giving */JOIN foobar* will also created the connection as current SILC Server version supports only global channels (all JOINs require connection to router, if one is configured). **prefer\_passphrase\_auth** If both public key and passphrase authentication are set for a connection, public key authentication is by default preferred. Setting this value to *true* causes silcd to prefer passphrase authentication in these cases. **require\_reverse\_lookup** Set this value to *true* if all connecting hosts must have a fully qualified domain name (FQDN). If set to true, a host without FQDN is not allowed to connect to server. **connections\_max** Maximum number of incoming connections to this server. Any further connections are refused. **connections\_max\_per\_host** Maximum number of incoming connections from any single host. This setting can be overridden on a connection-specific basis with *ConnectionParams*. **version\_protocol** Defines the minimum required version of protocol to allow connecting to server. A client or server using this version of protocol or newer is allowed to connect, one using anything older will be rejected. Leaving unset allows all versions to connect. This can be overridden with *ConnectionParams*. **version\_software** Defines the minimum required version of software to allow connecting to server. A client or server that is of this version or newer is allowed to connect, one using anything older will be rejected. Leaving unset allows all versions to connect. This can be overridden with *ConnectionParams*. **version\_software\_vendor** Defines the allowed software vendor string that is required to connect. Usually this is either a build number or special client tag. Using this requirement is not encouraged unless the server is in very limited use. Leaving unset allows all versions regardless of their vendor to connect. Can be overridden with *ConnectionParams*. **key\_exchange\_rekey** Defines the interval, in seconds, how often the session key will be regenerated. This setting only applies to the connection initiator, as rekey is always performed by the initiating party. Setting has effect only when the server acts as an initiator, and can be overridden with *ConnectionParams*. **key\_exchange\_pfs** Boolean value to determine, whether key-exchange is performed with Perfect Forward Secrecy (PFS) or without. If set to *true*, the rekey process will be somewhat slower, but more secure since the key is entirely regenerated. Can be overridden with *ConnectionParams*. **key\_exchange\_timeout** Key exchange timeout in seconds. If the key exchange is not completed within this time, the remote connection will be closed. **conn\_auth\_timeout** Connection authentication timeout in seconds. If the connection authentication is not completed within this time, the remote connection will be closed. **channel\_rekey\_secs** Seconds, how often channel key will be regenerated. Note that channel key is regenerated each time someone joins or leaves the channel. This is the maximum time any channel can have the same key. **detach\_disabled** Boolean value controlling, whether clients are denied the use of DETACH command. Default value is false (DETACH is allowed). **detach\_timeout** Time in seconds how long detached sessions will be available. By default, detached sessions do not expire and as such, are persistent as long as the server is running. If DETACH command is allowed, this value should be set as well. **qos** Boolean value controlling, whether Quality of Service settings are enabled. Default setting is false. NOTE: If you enable QoS in general section, it applies to every connection the server has, including server connections. This setting can be overridden with *ConnectionParams* and in case of server connections, it SHOULD BE overridden (server connections should not use QoS). **qos\_rate\_limit** Limits read operations per second to given amount. Do note that one read operation may read several SILC packets, so this setting does not automatically correspond to amount of messages transmitted or accepted. **qos\_bytes\_limit** Limits incoming SILC data to the specified number of bytes per second. **qos\_limit\_sec** This value defines the timeout, in seconds, for the delay of received data in case it was left in a QoS queue. **qos\_limit\_usec** This value defines the timeout, in microseconds, for the delay of received data for received data in case it was left in a QoS queue. ## SECTION: ServerInfo *ServerInfo* contains values for bound interfaces and administrative info. **hostname** Server's name (FQDN). **ServerType** This is a descriptive text field, usually telling what the server and its purpose are. **Location** Descriptive field of server's geographic location. **Admin** Administrator's full name. **AdminEmail** Administrator's email address. **User** The name of the user account silcd will be running on. This must be an existing user. Silcd needs to executed as root; after binding the port it will drop root privileges and use the account given here. **Group** The name of the group silcd will be running on. This must be an existing group. Silcd needs to be executed as root; after binding the port it will drop root privileges and use the group given here. **PublicKey** Full path to server's public key file. **PrivateKey** Full path to server's private key file. **MotdFile** Full path to MOTD (Message Of The Day) file, a text file that will be displayed to each client upon connection. **PidFile** Full path to file where silcd will write its PID. ## SUBSECTION: Primary This is the primary listener info. Each server can have no more than one *Primary* section. **ip** Specifies the address silcd is listening on. **port** Specifies the port silcd is listening on. **public\_ip** Optional field. If your server is behind NAT this IP would be the public IP address. The 'ip' field would include the internal IP address. With this option it is possible to run silcd behind NAT device. ## SUBSECTION: Secondary This is a secondary listener info. A server may have any amount of *Secondary* listener settings. These are needed only if silcd needs to listen on several interfaces. *Secondary* subsections have the same information that *Primary* does. ## SECTION: Logging This section is used to set up various log files; their paths, maximum sizes and individual logging options. There are four defined logging channels. The log channels have an importance value, and more important channels are always redirected to the less important ones. Setting a valid logging file for *Info* will ensure logging for all channels, whereas a setting for *Errors* would only ensure logging for *Errors* and *Fatals*. **Timestamp** A boolean value that dictates whether log lines will have timestamps prefixed. In general, this is a good idea. You might want to disable this if you are running silcd under some special logging daemon, such as daemontools. **QuickLogs** A boolean value that determines how often log files are updated. Setting this to *true* makes silcd log in real-time. Setting this to *false* makes silcd write to logs every *FlushDelay* seconds. Real-time logging causes a bit more CPU and HDD usage but reduces memory consumption. **FlushDelay** Time in seconds, how often logs are flushed to logfiles. This setting has effect only if *QuickLogs* is disabled. ## SUBSECTION: Info ## SUBSECTION: Warnings ## SUBSECTION: Errors ## SUBSECTION: Fatals Each of these subsections has the same attributes, *File* and *Size*. Different levels of problems are logged to their respective channels (*Info*, *Warnings*, *Errors*, *Fatals*), depending on their need of attention. **File** Full path to log file. **Size** Limit the size the log file is allowed to grow to. Any further messages to this file cause the oldest lines to be removed in order to keep the file size within given limit. ## SECTION: ConnectionParams This section defines connection parameters. Each connection may have its own set of *ConnectionParams* but having one is in no way mandatory. If no separate parameters have been assigned, the defaults and the ones from *General* section will be used. A silcd configuration may have any number of *ConnectionParams* sections. **name** This is a unique name that separates **this** particular *ConnectionParams* section from all the others. It is also the name with which settings are referred to a given set of parameters. This field is mandatory. **connections\_max** Limits how many concurrent connections are allowed. Any further connections are simply refused. Note that this setting can not override the figure given in *General* section. **connections\_max\_per\_host** Maximum number of connections allowed from any single host. If this parameter is set for a block controlling server connections, it is highly suggested to use a value of one (1). **version\_protocol** Exactly the same as in *General* section. **version\_software** Exactly the same as in *General* section. **version\_software\_vendor** Exactly the same as in *General* section. **keepalive\_secs** How often (seconds) to send HEARTBEAT packets to connected clients. **reconnect\_count** When connection is lost, how many times a reconnection is tried. **reconnect\_interval** How often, in seconds, a reconnection is attempted. **reconnect\_interval\_max** Reconnection time is lengthened each time an unsuccessful attempt occurs. This value defines the maximum interval to which the delay may be prolonged. **reconnect\_keep\_trying** Boolean value controlling whether server eventually gives up trying to reconnect. If set to *false*, server will give up once *reconnect\_count* is reached or, even at maximum interval no connection is established. **key\_exchange\_rekey** Exactly the same as in *General* section. **key\_exchange\_pfs** Exactly the same as in *General* section. **anonymous** This boolean setting has meaning only to client connections. If set to *true*, client connections using this *ConnectionParams* block will have their username and host scrambled. The client will also have an anonymous mode set to it. **qos** Exactly the same as in *General* section NOTE: For server connection this should be set to *false* value. **qos\_rate\_limit** Exactly the same as in *General* section. **qos\_bytes\_limit** Exactly the same as in *General* section. **qos\_limit\_sec** Exactly the same as in *General* section. **qos\_limit\_usec** Exactly the same as in *General* section. ## SECTION: Client This section defines how incoming client connections are handled. There can be several *Client* sections, each with their own requirements. A **silcd** admin could for example require that connections from certain IP-address space must supply a connection password. **Host** An address or wildcarded set of addresses, either in numeric IP-address fashion or as hostnames. For example *"10.1.\*"* or *"\*.mydomain.domain.org"*. **Passphrase** The required passphrase to allow client connection. **PublicKey** The path to a file containing the client's public key. There can be any number of *PublicKey* statements in one *Client* section. Matching any of them will do. **Params** Name of client connection parameters. ## SECTION: ServerConnection This section defines a configured server connection. A regular SILC server does not need one at all. If this block exists, it means that the server is a SILC router. There must be one *ServerConnection* for each SILC server that connects to this router. **Host** Either an FQDN or strict IP-address of the connecting server. **Passphrase** If server connection requires passphrase authentication, set it here. **PublicKey** This is a path to connecting server's public key. If server connection requires public key authentication, set this value. If both *Passphrase* and *PublicKey* are set, then either of them will be accepted. **Params** Connection parameters. **Backup** A boolean value controlling whether this server acts as a backup. Set to *false* for normal servers. If set to *true*, this server is a backup router. ## SECTION: RouterConnection This section covers router connections. Stand-alone servers won't have this section, and regular servers should only have one. Router servers need one *RouterConnection* for each other router they have been configured to connect to. First configured section is the primary route. **Port** If *Initiator* is set tro *true*, this setting defines the remote port in which to connect. if *Initiator* is set to false, then this defines the local (listening) port. **Passphrase** If connecting server requires a passphrase authentication, it is set here. **PublicKey** If connecting to server requires public key authentication, the path to server's public key file is set here. **Params** Connection parameters. **Initiator** A boolean setting that defines whether this server is the connecting party. **BackupHost** If the configured connection is a backup connection, set this to the address of the main router that will be replaced. For normal router connection leave this option out. **BackupPort** If the configured connection is a backup connection, set this to the remote port which to connect to. For normal router connection, leave this option out. **BackupLocal** A boolean value. If this setting is *true*, then the backup router is in the same cell. If the backup router is in another cell, set this to *false*. Needless to say, for normal router connection, leave this option out. ## SECTION: Admin This section defines configured administration connections. **Host** Either FQDN or a strict IP-address to the origin of connection. This field is optional. **User** Username that the connecting client announces. This field is optional. **Nick** Nickname that the connecting client announces. This field is optional. **Passphrase** Passphrase required to obtain server operator privileges. **PublicKey** Path to administrator's public key file. If both *Passphrase* and *PublicKey* are defined, either one can be used. ## SECTION: Deny This section defines denied incoming connections. They apply equally to both client and server connections, so make sure you know what you add here. Each *Deny* section covers one instance of denied connection(s). There may be any number of *Deny* sections. **Host** Address or wildcarded addresses of denied connections. **NOTE!** This field is not mandatory, but highly recommended. If you don't specify *Host* at all, or give it a value of "\*", you have a silcd that denies every single incoming connection. **Reason** A string giving the reason as to why the connecting party is not allowed to connect. Unlike *Host*, this field IS mandatory. ## FILES **silcd.conf** ## SEE ALSO **[silcd(8)](/silcd/8.md)** ## AUTHOR SILC is designed and written by Pekka Riikonen \ and rest of the SILC Project. Configuration file format and parser is by Giovanni Giacobbi \. This manpage was written by Mika 'Bostik' Boström \ See **CREDITS** for full list of contributors.