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sks

sks

Section: SKS OpenPGP Key server (8) Updated: 2009-03-29
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NAME

SKS - Synchronizing Key Server  

SYNOPSIS

sks [options] -debug  

DESCRIPTION

SKS is a OpenPGP keyserver whose goal is to provide easy to deploy, decentralized, and highly reliable synchronization. That means that a key submitted to one SKS server will quickly be distributed to all key servers, and even wildly out-of-date servers, or servers that experience spotty connectivity, can fully synchronize with rest of the system.

The design of SKS is deliberately simple. The server consists of two single-threaded processes. The first, ``sks db'', fulfills the normal jobs associated with a public key server, such as answering web requests. The only special functionality of ``sks db'' is that it keeps a log summarizing the changes to the key database. ``sks recon'' does all the work with respect to reconciling hosts databases. ``sks recon'' keeps track of specialized summary information about the database, and can use that information to efficiently determine the differences between its database and that of another host.  

FEATURES

Highly efficient and reliable reconciliation algorithm

Follows RFC2440 and RFC2440bis carefully - unlike PKS, SKS supports new and old style packets, photoID packets, multiple subkeys, and pretty much everything allowed by the RFCs.

Fully compatible with PKS system - can both send and receive syncs from PKS servers, ensuring seamless connectivity.

Simple configuration: each host just needs a (partial) list of the other participating key servers. Gossip is used to distribute information without putting a heavy load an any one host.

Supports HKP/web-based querying, and soon-to-be-standard machine readable indices  

OPTIONS

SKS binary command options are as follows:
db
 Initiates database server.

recon
Initiates reconciliation server.
cleandb
Apply filters to all keys in database, fixing some common problems.
build
Build key database, including body of keys directly in database.
fastbuild -n [size] -cache [mbytes]
Build key database, doesn't include keys directly in database, faster than build. -n specifies the mulitple of 15000 keys to read in at once, and -cache specifies the database cache to use in megabytes.
pbuild -cache [mbytes] -ptree_cache [mbytes]
Build prefix-tree database, used by reconciliation server, from key database. Allows for specification of cache for key database and for ptree database.
dump #keys dumpdir
Create a raw dump of the keys in the database.
merge
Adds key from key files to existing database.
drop
Drops key from database.
update_subkeys [-n # of updates / 1000]
Updates subkey keyid index to include all current keys. Only useful when upgrading versions 1.0.4 or before of SKS.
help
Prints the help message.
 

ADDITIONAL OPTIONS

You won't need most of the options below for normal operation. These options can be given in basedir/sksconf or as command line option for the sks binary.
-debug
Debugging mode.
-debuglevel
Debugging level --- sets verbosity of logging.
-q
 Number of bits defining a bin.

-mbar
Number of errors that can be corrected in one shot.
-seed
Seed used by RNG.
-hostname
Current hostname.
-d
 Number of keys to drop at random when synchronizing.

-n
 Multiple of 15,000 keys to load at once.

-max_internal_matches
Maximum number of matches for most specific word in a multi-word search.
-max_matches
Maximum number of matches that will be returned from a query.
-max_uid_fetches
Maximum number of uid fetches performed in a verbose index query.
-pagesize
Pagesize in bytes for key db.
-cache
Cache size in megs for key db.
-ptree_pagesize
Pagesize in bytes for prefix tree db.
-ptree_cache
Cache size in megs for prefix tree db.
-baseport
Set base port number.
-recon_port
Set recon port number.
-recon_address
Set recon binding address. Can be a list of whitespace separated IP addresses.
-hkp_port
Set hkp port number.
-hkp_address
Set hkp binding address. Can be a list of whitespace separated IP addresses.
-use_port_80
Have the HKP interface listen on port 80, as well as the hkp_port.
-basedir
Set base directory.
-stdoutlog
Send log messages to stdout instead of log file.
-diskptree
Use a disk-based ptree implementation. Slower, but requires far less memory.
-nodiskptree
Use in-mem ptree.
-max_ptree_nodes
Maximum number of allowed ptree nodes. Only meaningful if -diskptree is set.
-prob
Set probability. Used for testing code only.
-recon_sync_interval
Set sync interval for reconserver.
-gossip_interval
Set time between gossips in minutes.
-dontgossip
Don't gossip automatically. Host will still respond to requests from other hosts.
-db_sync_interval
Set sync interval for dbserver.
-checkpoint_interval
Time period between checkpoints.
-recon_checkpoint_interval
Time period between checkpoints for reconserver.
-ptree_thresh_mult
Multiple of thresh which specifies minimum node size in prefix tree.
-recon_thresh_mult
Multiple of thresh which specifies minimum node size that is included in reconciliation.
-max_recover
Maximum number of differences to recover in one round.
-http_fetch_size
Number of keys for reconserver to fetch from dbserver in one go.
-wserver_timeout
Timeout in seconds for webserver requests.
-reconciliation_timeout
Timeout for reconciliation runs in minutes.
-stat_hour
Hour at which to run database statistics.
-initial_stat
Runs database statistics calculation on boot.
-reconciliation_config_timeout
Set timeout in seconds for initial exchange of config info in reconciliation.
-missing_keys_timeout
Timeout in seconds for get_missing_keys.
-command_timeout
Timeout in seconds for commands set over command socket.
-sendmail_cmd
Command used for sending mail.
-from_addr
From address used in synchronization emails used to communicate with PKS.
-dump_new_only
When doing a database dump, only dump new keys, not keys already contained in a keydump file.
-max_outstanding_recon_requests
Maximum number of outstanding requests in reconciliation.
-membership_reload_interval
Maximum interval (in hours) at which membership file is reloaded.
--help, -help
Displays list of options.
 

FILES

Information about important files located in your SKS basedir.
bin/sks
The main SKS executable.
bin/sks_add_mail
The executable responsible for parsing incoming mails from PKS key servers.
bin/sks_build.sh
Script to generate an initial database.
mailsync
The mailsync should contains a list of email addresses of PKS keyservers. This file is important, because it ensures that keys submitted directly to an SKS keyserver are also forwarded to PKS keyservers. IMPORTANT : don't add someone to your mailsync file without getting their permission first!
membership
With SKS, two hosts can efficiently compare their databases then repair whatever differences are found. In order to set up reconciliation, you first need to find other SKS servers that will agree to gossip with you. The hostname and port of the server that has agreed to do so should be added to this file.
sksconf
The configuration file for your SKS server.
 

EXAMPLES

membership
 keyserver.ahost.org 11370 # Comments are allowed
 keyserver.foo.org 11370   # Another host with default ports

sksconf
 membership_reload_interval: 1
 initial_stat:
 hostname: keyserver.example.com
 from_addr: pgp-public-keys@keyserver.example.com

Procmail
 PATH=/path/of/sks/exectuables
 :0 
 * ^Subject: incremental
 | /path/of/sks_add_mail /path/to/sks/directory

/etc/aliases
 pgp-public-keys:      "|/path/of/sks_add_mail /path/to/sks/directory"

 

SEE ALSO

 The SKS website is located at http://minskyprimus.net/sks/.

 

AUTHOR

The first draft was written by Thomas Sjogren <thomas@northernsecurity.net>.


 

Index

NAME
SYNOPSIS
DESCRIPTION
FEATURES
OPTIONS
ADDITIONAL OPTIONS
FILES
EXAMPLES
SEE ALSO
AUTHOR

This document was created by man2html, using the manual pages.
Time: 22:02:23 GMT, April 16, 2011