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RELAYD.CONF(5)		       File Formats Manual		  RELAYD.CONF(5)

NAME
     relayd.conf -- relay daemon configuration file

DESCRIPTION
     relayd.conf is the configuration file for the relay daemon, relayd(8).

     relayd.conf is divided into the following main sections:

     Macros
	   User-defined variables may be defined and used later, simplifying the
	   configuration file.

     Global Configuration
	   Global  settings  for relayd(8).  Do note that the config file allows
	   global settings to be added after defining tables in the config file,
	   but those tables will use the built-in defaults instead of the global
	   settings below them.

     Tables
	   Table definitions describe a list of hosts, in a similar  fashion  to
	   pf(4)  tables.  They are used for relay and redirection target selec-
	   tion with the described options and health checking on the host  they
	   contain.

     Redirections
	   Redirections  are  translated to pf(4) rdr-to rules for stateful for-
	   warding to a target host from a health-checked table on layer 3.

     Relays
	   Relays allow application layer load balancing, TLS acceleration,  and
	   general purpose TCP proxying on layer 7.

     Protocols
	   Protocols are predefined settings and filter rules for relays.

     Within  the sections, a host address can be specified by IPv4 address, IPv6
     address, interface name, interface group, or DNS hostname.  If the  address
     is an interface name, relayd(8) will look up the first IPv4 address and any
     other  IPv4  and IPv6 addresses of the specified network interface.  A port
     can be specified by number or name.  The port name to number  mappings  are
     found in the file /etc/services; see services(5) for details.

     The  current  line  can  be  extended over multiple lines using a backslash
     (`\').  Comments can be put anywhere in the file using a hash  mark  (`#'),
     and  extend to the end of the current line.  Care should be taken when com-
     menting out multi-line text: the comment is effective until the end of  the
     entire block.

     Argument  names  not  beginning with a letter, digit, or underscore must be
     quoted.

     Additional configuration files can be included with  the  include	keyword,
     for example:

	   include "/usr/local/etc/relayd.conf.local"

MACROS
     Macros  can be defined that will later be expanded in context.  Macro names
     must start with a letter, digit, or underscore,  and  may	contain  any  of
     those  characters.   Macro  names	may  not be reserved words (for example,
     table, relay, or timeout).  Macros are not expanded inside quotes.

     For example:

	   www1="10.0.0.1"
	   www2="10.0.0.2"
	   table <webhosts> {
		   $www1
		   $www2
	   }

GLOBAL CONFIGURATION
     Here are the settings that can be set globally:

     agentx [context context] [path path]
	     Export relayd(8) metrics via an agentx compatible (snmp) daemon  by
	     connecting  to  path.   Metrics can be found under the relaydMIBOb-
	     jects subtree (enterprises.30155.3).  If path is omitted,	it  will
	     default  to  /var/agentx/master.  Context is the SNMPv3 context and
	     can usually be omitted.

     interval number
	     Set the interval in seconds at which the  hosts  will  be	checked.
	     The default interval is 10 seconds.

     log (state changes|host checks)
	     Log  host checks: Either log only the state changes of hosts or log
	     all host checks that were run, even if  the  state  didn't  change.
	     The  host	state  can  be "up" (the health check completed success-
	     fully), "down" (the host is down or didn't match the  check  crite-
	     ria),  or	"unknown"  (the host is disabled or has not been checked
	     yet).

     log connection [errors]
	     When using relays, log all TCP connections.   Optionally  log  only
	     connection errors.

     prefork number
	     When  using relays, run the specified number of processes to handle
	     relayed connections.  This increases the performance  and	prevents
	     delays  when  connecting  to  a  relay.   relayd(8)  runs	3  relay
	     processes by default and every process will handle  all  configured
	     relays.

     socket "path"
	     Create  a	control socket at path.  By default /var/run/relayd.sock
	     is used.

     timeout number
	     Set the global timeout in milliseconds for  checks.   This  can  be
	     overridden  by the timeout value in the table definitions.  The de-
	     fault timeout is 200 milliseconds and it must not exceed the global
	     interval.	The default value is optimized	for  checks  within  the
	     same  collision  domain  -  use a higher timeout, such as 1000 mil-
	     liseconds, for checks of hosts in other subnets.  If this option is
	     to be set, it should be placed before overrides in tables.

TABLES
     Tables are used to group a set of hosts as the target for	redirections  or
     relays;  they will be mapped to a pf(4) table for redirections.  Tables may
     be defined with the following attribute:

     disable  Start the table disabled - no hosts will be checked in this table.
	      The table can be later enabled through relayctl(8).

     Each table must contain at least one host address; multiple hosts are sepa-
     rated by newline, comma, or whitespace.  Host entries may be  defined  with
     the following attributes:

     ip ttl number
	    Change  the  default  time-to-live	value in the IP headers for host
	    checks.

     parent number
	    The optional parent option inherits the state  from  a  parent  host
	    with  the  specified identifier.  The check will be skipped for this
	    host and copied from the parent host.  This can be used  to  prevent
	    multiple  checks  on  hosts  with multiple IP addresses for the same
	    service.  The host identifiers are sequentially assigned to the con-
	    figured hosts starting with 1; it can be shown with the  relayctl(8)
	    show summary commands.

     priority number
	    Change  the  route priority used when adding a route.  If not speci-
	    fied, the kernel will set a priority of 8 (RTP_STATIC).  In ordinary
	    use, a fallback route should be added statically with  a  very  high
	    (e.g. 52) priority.  Unused in all other modes.

     retry number
	    The  optional  retry option adds a tolerance for failed host checks;
	    the check will be retried for number more times before  setting  the
	    host  state to down.  If this table is used by a relay, it will also
	    specify the number of retries for outgoing connection attempts.

     For example:

	   table <service> { 192.168.1.1, 192.168.1.2, 192.168.2.3 }
	   table <fallback> disable { 10.1.5.1 retry 2 }

	   redirect "www" {
		   listen on www.example.com port 80
		   forward to <service> check http "/" code 200
		   forward to <fallback> check http "/" code 200
	   }

     Tables are used by forward to directives in redirections or relays  with  a
     set  of  general  options,  health-checking  rules,  and  timings;  see the
     "REDIRECTIONS" and "RELAYS" sections for more information about the forward
     context.  Table specific  configuration  directives  are  described  below.
     Multiple  options	can  be  appended to forward to directives, separated by
     whitespaces.

     The following options will configure the health-checking method for the ta-
     ble, and is mandatory for redirections:

     check http path [host hostname] code number
	     For each host in the table, verify that  retrieving  the  URL  path
	     gives the HTTP return code number.  If hostname is specified, it is
	     used as the "Host:" header to query a specific hostname at the tar-
	     get  host.   To  validate the HTTP return code, use this shell com-
	     mand:

		   $ echo -n "HEAD <path> HTTP/1.0\r\n\r\n" | \
			   nc <host> <port> | head -n1

	     This prints the status header including the actual return code:

		   HTTP/1.1 200 OK

     check https path [host hostname] code number
	     This has the same effect as above but wraps  the  HTTP  request  in
	     TLS.

     check http path [host hostname] digest string
	     For  each	host  in  the table, verify that retrieving the URL path
	     produces non-binary content whose message digest  matches	the  de-
	     fined  string.   The  algorithm  used  is	determined by the string
	     length of the digest argument, either SHA1 (40 characters)  or  MD5
	     (32  characters).	 If  hostname  is  specified,  it is used as the
	     "Host:" header to query a specific hostname  at  the  target  host.
	     The  digest  does	not  take the HTTP headers into account.  Do not
	     specify a binary object (such as a graphic) as the  target  of  the
	     request,  as  relayd.conf expects the data returned to be a string.
	     To compute the digest, use this simple command:

		   $ ftp -o - http://host[:port]/path | sha1

	     This gives a digest that can be used as-is in a digest statement:

		   a9993e36476816aba3e25717850c26c9cd0d89d

     check https path [host hostname] digest string
	     This has the same effect as above but wraps  the  HTTP  request  in
	     TLS.

     check icmp
	     Ping  hosts  in this table to determine whether they are up or not.
	     This method will automatically use ICMP or ICMPV6 depending on  the
	     address family of each host.

     check script path
	     Execute  an  external program to check the host state.  The program
	     will be executed for each host by specifying the  hostname  on  the
	     command line:

		   /usr/local/bin/checkload.pl front-www1.private.example.com

	     relayd(8)	expects  a  positive return value on success and zero on
	     failure.  Note that the script will be executed with the privileges
	     of the "_relayd" user and terminated after timeout milliseconds.

     check send data expect pattern [tls]
	     For each host in the table, a TCP connection is established on  the
	     port  specified, then data is sent.  Incoming data is then read and
	     is expected to match against pattern using  shell	globbing  rules.
	     If  data  is an empty string or nothing then nothing is sent on the
	     connection and data is immediately read.  This can be  useful  with
	     protocols	that  output  a banner like SMTP, NNTP, and FTP.  If the
	     tls keyword is present, the transaction will occur in a TLS tunnel.

     check binary send data expect data [tls]
	     For each host in the table, a TCP connection is established on  the
	     port  specified,  then  the  send data is converted into binary and
	     sent.  Incoming (binary) data is then read and is expected to match
	     against a binary conversion of the  expect  data  using  memcmp(3).
	     data  must  be populated with a string containing an even number of
	     hexadecimal single-byte characters and must not be empty.	This can
	     be useful with binary protocols such as LDAP and SNMP.  If the  tls
	     keyword is present, the transaction will occur in a TLS tunnel.

     check tcp
	     Use a simple TCP connect to check that hosts are up.

     check tls
	     Perform  a  complete  TLS	handshake  with each host to check their
	     availability.

     The following general table options are available:

     interval number
	     Override the global interval and specify one for  this  table.   It
	     must be a multiple of the global interval.

     timeout number
	     Set the timeout in milliseconds for each host that is checked using
	     TCP as the transport.  This will override the global timeout, which
	     is 200 milliseconds by default.

     The  following  options  will set the scheduling algorithm to select a host
     from the specified table:

     mode hash [key]
	     Balances the outgoing connections across the active hosts based  on
	     the key, IP address and port of the relay.  Additional input can be
	     fed into the hash by looking at HTTP headers and GET variables; see
	     the  "PROTOCOLS" section below.  This mode is only supported by re-
	     lays.

     mode least-states
	     Forward each outgoing connection to the active host with the  least
	     active pf(4) states.  This mode is only supported by redirections.

     mode loadbalance [key]
	     Balances  the outgoing connections across the active hosts based on
	     the key, the source IP address of the client, and	the  IP  address
	     and port of the relay.  This mode is only supported by relays.

     mode random
	     Distributes  the  outgoing  connections randomly through all active
	     hosts.  This mode is supported by redirections and relays.

     mode roundrobin
	     Distributes the outgoing connections using a round-robin  scheduler
	     through  all  active  hosts.   This is the default mode and will be
	     used if no option has been specified.  This mode  is  supported  by
	     redirections and relays.

     mode source-hash [key]
	     Balances  the outgoing connections across the active hosts based on
	     the key and the source IP address of the client.  This mode is sup-
	     ported by redirections and relays.

     The optional key argument can be specified for the hash,  loadbalance,  and
     source-hash modes as either a hex value with a leading `0x' or as a string.
     If  omitted,  relayd(8)  generates  a  random key when the configuration is
     loaded.

REDIRECTIONS
     Redirections represent a pf(4) rdr-to rule.  They	are  used  for	stateful
     redirections to the hosts in the specified tables.  pf(4) rewrites the tar-
     get  IP addresses and ports of the incoming connections, operating on layer
     3.  The configuration directives that are valid in the redirect context are
     described below:

     disable
	     The redirection is initially disabled.  It  can  be  later  enabled
	     through relayctl(8).

     forward to <table> [port number] options ...
	     Specify  the  tables  of  target hosts to be used; see the "TABLES"
	     section above for information about table options.  If the port op-
	     tion is not specified, the first port from the listen on  directive
	     will  be  used.  This directive can be specified twice - the second
	     entry will be used as the backup table if all hosts in the main ta-
	     ble are down.  At least one entry for the main table is mandatory.

     listen on address [ip-proto] port port [interface name]
	     Specify an address and a port to listen on.   pf(4)  will	redirect
	     incoming  connections  for the specified target to the hosts in the
	     main or backup table.  The port argument can optionally  specify  a
	     port   range   instead   of   a   single	port;	the   format  is
	     min-port:max-port.  The optional argument ip-proto can be	used  to
	     specify  an  IP  protocol like tcp or udp; it defaults to tcp.  The
	     rule can be optionally restricted to a given interface name.

     [match] pftag name
	     Automatically tag packets passing through	the  pf(4)  rdr-to  rule
	     with the name supplied.  This allows simpler filter rules.  The op-
	     tional match keyword will change the default rule action from `pass
	     in quick' to `match in' to allow further evaluation in the pf rule-
	     set using the tagged name rule option.

     route to <table> [port number] options ...
	     Like  the	forward to directive, but directly routes the packets to
	     the target host without modifying the target address using a  pf(4)
	     route-to  rule.   This  can  be  used for "direct server return" to
	     force the target host to respond via  a  different  gateway.   Note
	     that  hosts  have	to  accept  sessions for the same address as the
	     gateway, which is typically done by configuring a	loopback  inter-
	     face on the host with this address.

     session timeout seconds
	     Specify  the inactivity timeout in seconds for established redirec-
	     tions.  The default timeout is 600 seconds (10 minutes).  The maxi-
	     mum is 2147483647 seconds (68 years).

     sticky-address
	     This has the same effect as specifying sticky-address for an rdr-to
	     rule in pf.conf(5).  It will ensure that multiple connections  from
	     the same source are mapped to the same redirection address.

RELAYS
     Relays  will forward traffic between a client and a target server.  In con-
     trast to redirections and IP forwarding in the network stack, a relay  will
     accept incoming connections from remote clients as a server, open an outgo-
     ing connection to a target host, and forward any traffic between the target
     host  and	the remote client, operating on layer 7.  A relay is also called
     an application layer gateway or layer 7 proxy.

     The main purpose of a relay is to provide advanced load balancing function-
     ality based on specified protocol characteristics, such as HTTP headers, to
     provide TLS acceleration and to allow basic handling of the underlying  ap-
     plication protocol.

     The relay configuration directives are described below:

     disable
	     Start the relay but immediately close any accepted connections.

     [transparent] forward [with tls] to address [port port] options ...
	     Specify  the address and port of the target host to connect to.  If
	     the port option is not specified, the port from the listen  on  di-
	     rective will be used.  Use the transparent keyword to enable fully-
	     transparent mode; the source address of the client will be retained
	     in this case.

	     The  with	tls directive enables client-side TLS mode to connect to
	     the remote host.  Verification of server certificates  can  be  en-
	     abled by setting the ca file option in the protocol section.

	     The following options may be specified for forward directives:

	     inet    If  the requested destination is an IPv6 address, relayd(8)
		     will forward the connection to an IPv4 address which is de-
		     termined by the last 4 octets of the original IPv6 destina-
		     tion.  For example, if the original  IPv6	destination  ad-
		     dress  is	2001:db8:7395:ffff::a01:101,  the session is re-
		     layed to the IPv4 address 10.1.1.1 (a01:101).

	     inet6 address-prefix
		     If the requested destination is an IPv4 address,  relayd(8)
		     will forward the connection to an IPv6 address which is de-
		     termined by setting the last 4 octets of the specified IPv6
		     address-prefix  to the 4 octets of the original IPv4 desti-
		     nation.  For example, if the original IPv4 destination  ad-
		     dress  is	10.1.1.1  and  the  specified  address prefix is
		     2001:db8:7395:ffff::, the session is relayed  to  the  IPv6
		     address 2001:db8:7395:ffff::a01:101.

	     retry number
		     The  optional host retry option will be used as a tolerance
		     for failed host connections; the connection will be retried
		     for number more times.

     forward to <table> [port port] options ...
	     Like the previous directive, but connect to a host from the  speci-
	     fied  table;  see	the "TABLES" section above for information about
	     table options.  This directive can be specified  multiple	times  -
	     subsequent entries will be used as the backup table if all hosts in
	     the previous table are down.  At least one entry for the main table
	     is  mandatory.   As  above,  use  the  with tls directive to enable
	     client-side TLS mode when connecting to the remote host.

     forward to destination options ...
	     When redirecting connections with a rdr-to rule in pf.conf(5) to  a
	     relay  listening on localhost, this directive will look up the real
	     destination address of the intended target host, allowing the relay
	     to be run as a transparent proxy.	If an additional forward to  di-
	     rective to a specified address or table is present, it will be used
	     as  a  backup if the NAT lookup failed.  As above, use the with tls
	     directive to enable client-side TLS mode when connecting to the re-
	     mote host.

     listen on address port port [tls]
	     Specify the address and port for the relay to listen on.  The relay
	     will accept incoming connections to the specified address.  If  the
	     tls keyword is present, the relay will accept connections using the
	     encrypted TLS protocol.

     protocol name
	     Use  the  specified protocol definition for the relay.  The generic
	     TCP protocol options will be used by default; see	the  "PROTOCOLS"
	     section below.

     session timeout seconds
	     Specify  the  inactivity  timeout in seconds for accepted sessions.
	     The default timeout is 600 seconds (10 minutes).	The  maximum  is
	     2147483647 seconds (68 years).

TLS RELAYS
     In  addition  to plain TCP, relayd(8) supports the Transport Layer Security
     (TLS) cryptographic protocol for authenticated and encrypted  relays.   re-
     layd(8) can operate as a TLS client or server to offer a variety of options
     for different use cases related to TLS.

     TLS client
	     When configuring the relay forward statements with the with tls di-
	     rective,  relayd(8)  will	enable client-side TLS to connect to the
	     remote host.  This is commonly used for TLS tunneling and transpar-
	     ent encapsulation of plain TCP connections.  See the forward to de-
	     scription in the "RELAYS" section for more details.

     TLS server
	     When specifying the tls keyword in the relay listen statements, re-
	     layd(8) will accept connections from clients as a TLS server.  This
	     mode is also known as "TLS acceleration".	See the  listen  on  de-
	     scription in the "RELAYS" section for more details.

     TLS client and server
	     When  combining  both  modes,  TLS server and client, relayd(8) can
	     filter TLS connections as a man-in-the-middle.  This combined  mode
	     is  also called "TLS inspection".	The configuration requires addi-
	     tional X.509 certificate settings; see the ca  key  description  in
	     the "PROTOCOLS" section for more details.

     When configured for "TLS inspection" mode, relayd(8) will listen for incom-
     ing connections which have been diverted to the local socket by PF.  Before
     accepting	and negotiating the incoming TLS connection as a server, it will
     look up the original destination address on the diverted socket,  and  pre-
     connect  to the target server as a TLS client to obtain the remote TLS cer-
     tificate.	It will update or patch the obtained TLS certificate by  replac-
     ing  the  included  public key with its local server key because it doesn't
     have the private key of the remote server certificate.  It also updates the
     X.509 issuer name to the local CA subject name and  signs	the  certificate
     with  its	local  CA key.	This way it keeps all the other X.509 attributes
     that are already present in the server certificate,  including  the  "green
     bar"  extended  validation attributes.  Now it finally accepts the TLS con-
     nection from the diverted client using the updated certificate and  contin-
     ues to handle the connection and to connect to the remote server.

PROTOCOLS
     Protocols are templates defining settings and rules for relays.  They allow
     setting  generic  TCP options, TLS settings, and rules for the selected ap-
     plication layer protocol.

     The protocol directive is available for a number of  different  application
     layer  protocols.	 There is no generic handler for UDP-based protocols be-
     cause it is a stateless datagram-based protocol which has to look into  the
     application layer protocol to find any possible state information.

     dns protocol
	     (UDP)  Domain Name System (DNS) protocol.	The requested IDs in the
	     DNS header will be used to match  the  state.   relayd(8)	replaces
	     these  IDs  with random values to compensate for predictable values
	     generated by some hosts.

     http protocol
	     Handle the HyperText Transfer Protocol (HTTP, or "HTTPS" if  encap-
	     sulated in a TLS tunnel).

     [tcp] protocol
	     Generic handler for TCP-based protocols.  This is the default.

     The available configuration directives are described below:

     (block|pass|match) [rule]
	     Specify one or more rules to filter connections based on their net-
	     work  or  application layer headers; see the "FILTER RULES" section
	     for more details.

     return error [option]
	     Return an error response to the client if an internal operation  or
	     the  forward connection to the client failed.  By default, the con-
	     nection will be silently dropped.	The effect of  this  option  de-
	     pends  on	the protocol: HTTP will send an error header and page to
	     the client before closing the connection.	Additional valid options
	     are:

	     style string
		     Specify a Cascading Style Sheet (CSS) to be  used	for  the
		     returned HTTP error pages, for example:

			   body { background: #a00000; color: white; }

     tcp option
	     Enable  or  disable  the  specified  TCP/IP options; see tcp(4) and
	     ip(4) for more information about the options.  Valid options are:

	     backlog number
		     Set the maximum length the queue of pending connections may
		     grow to.  The backlog option is 10 by default,  is  limited
		     to 512 and capped by the kern.somaxconn sysctl(8) variable.

	     ip minttl number
		     This option for the underlying IP connection may be used to
		     discard  packets with a TTL lower than the specified value.
		     This can be used to implement the Generalized TTL	Security
		     Mechanism (GTSM) according to RFC 5082.

	     ip ttl number
		     Change the default time-to-live value in the IP headers.

	     nodelay
		     Enable the TCP NODELAY option for this connection.  This is
		     recommended  to  avoid  delays  in the relayed data stream,
		     e.g. for SSH connections.	The default is no nodelay.

	     no splice
		     Disable socket splicing for zero-copy data  transfer.   The
		     default is to enable socket splicing.

	     sack    Use  selective  acknowledgements  for this connection.  The
		     default is no sack.

	     socket buffer number
		     Set the socket-level buffer size for input and  output  for
		     this connection.  This will affect the TCP window size.

     tls option
	     Set the TLS options and session settings.	This is only used if TLS
	     is enabled in the relay.  Valid options are:

	     ca cert path
		     Specify  a CA certificate for TLS inspection.  For more in-
		     formation, see the ca key option below.

	     ca file path
		     This option enables CA verification  in  TLS  client  mode.
		     The  daemon  will	load the CA (Certificate Authority) cer-
		     tificates from the specified path to verify the server cer-
		     tificates.   OpenBSD  provides  a	default  CA  bundle   in
		     /etc/ssl/cert.pem.

	     ca key path password password
		     Specify a CA key for TLS inspection.  The password argument
		     will  specify the password to decrypt the CA key (typically
		     an RSA key).  This option will enable TLS inspection if the
		     following conditions are true:

			   *   TLS server mode is enabled by the  listen  direc-
			       tive: listen on ... tls.
			   *   TLS client mode and divert lookups are enabled by
			       the   forward  directive:  forward  with  tls  to
			       destination.
			   *   The ca cert option is specified.
			   *   The ca key option is specified.

	     ciphers string
		     Set the string defining the TLS cipher suite.  If not spec-
		     ified, the default value `HIGH:!aNULL' will be used (strong
		     crypto cipher suites without anonymous DH).   See	the  CI-
		     PHERS  section  of openssl(1) for information about TLS ci-
		     pher suites and preference lists.

	     client-renegotiation
		     Allow client-initiated renegotiation.  To mitigate a poten-
		     tial DoS risk, the default is no client-renegotiation.

	     ecdhe curves
		     Specify a comma separated list of elliptic  curves  to  use
		     for  ECDHE cipher suites, in order of preference.	The spe-
		     cial value of "default" will use the  default  curves;  see
		     tls_config_set_ecdhecurves(3) for further details.

	     edh [params (none|auto|legacy)]
		     Enable EDH-based cipher suites with Perfect Forward Secrecy
		     (PFS) for older clients that do not support ECDHE.  In auto
		     mode,  the  key  size of the ephemeral key is automatically
		     selected based on the size of  the  private  key  used  for
		     signing.  In legacy mode, a 1024 bit ephemeral key is used.
		     If params is omitted, auto is used.  The default is no edh.

	     keypair name
		     The  relay  will  attempt	to  look  up  a  private  key in
		     /etc/ssl/private/name:port.key and a public certificate  in
		     /etc/ssl/name:port.crt,  where  port  is the specified port
		     that the relay listens on.  If these files are not present,
		     the     relay     will	continue     to     look      in
		     /etc/ssl/private/name.key	and /etc/ssl/name.crt.	This op-
		     tion can be specified multiple times for  TLS  Server  Name
		     Indication.  If not specified, a keypair will be loaded us-
		     ing  the  specified  IP  address of the relay as name.  See
		     ssl(8) for details about TLS server certificates.

		     An optional OCSP staple file will be used during TLS  hand-
		     shakes  with this server if it is found as a non-empty file
		     in /etc/ssl/name:port.ocsp or /etc/ssl/name.ocsp.	The file
		     should contain a DER-format OCSP response retrieved from an
		     OCSP server for the certificate in use, and can be  created
		     using ocspcheck(8).

	     no cipher-server-preference
		     Prefer  the  client's cipher list over the server's prefer-
		     ences when choosing a cipher for the connection.	The  de-
		     fault is to prefer the server's cipher list.

	     session tickets
		     Enable  TLS  session tickets.  relayd(8) supports stateless
		     TLS session tickets (RFC 5077) to implement TLS session re-
		     sumption for connections not using TLSv1.3.  The default is
		     to disable session tickets.

	     no tlsv1.3
		     Disable the TLSv1.3 protocol.  The  default  is  to  enable
		     TLSv1.3.

	     no tlsv1.2
		     Disable  the  TLSv1.2  protocol.	The default is to enable
		     TLSv1.2.

	     sslv3   Is deprecated and does nothing.

	     tlsv1   Enable all TLSv1 protocols.  This is  an  alias  that  cur-
		     rently  includes  tlsv1.2,  and tlsv1.3.  The default is no
		     tlsv1.

	     tlsv1.0
		     Is deprecated and does nothing.

	     tlsv1.1
		     Is deprecated and does nothing.

     http option
	     Set the HTTP options and session settings.  This is  only	used  if
	     HTTP is enabled in the relay.  Valid options are:

	     headerlen number
		     Set the maximum size of all HTTP headers in bytes.  The de-
		     fault  value  is  8192  and  it  is limited to a maximum of
		     131072.

	     websockets
		     Allow connection upgrade to websocket  protocol.	The  de-
		     fault is no websockets.

FILTER RULES
     Relays have the ability to filter connections based on their network or ap-
     plication	layer  headers.  Filter rules apply options to connections based
     on the specified filter parameters.

     For each connection that is processed by a  relay,  the  filter  rules  are
     evaluated in sequential order, from first to last.  For block and pass, the
     last  matching  rule  decides  what action is taken; if no rule matches the
     connection, the default action is to establish the connection  without  any
     additional  action.   For match, rules are evaluated every time they match;
     the pass/block state of a connection remains unchanged.

     The filter action may be one of the following:

     block   The connection is blocked.  If a block rule matches a  new  connec-
	     tion  attempt,  it  will  not be established.  block rules can also
	     trigger for existing connections after evaluating application layer
	     parameters; any connection of the relay session will  be  instantly
	     dropped.

     match   The  connection is matched.  This action does not alter the connec-
	     tion state, but allows additional parameters to the connection.

     pass    The connection is passed; relayd(8) will continue	to  process  the
	     relay session normally.

     These filter parameters can be used in the rules:

     request or response
	     A	relay session always consists of two connections: the request, a
	     client initiating a new connection to a server via the  relay,  and
	     the  response,  the  server accepting the connection.  Depending on
	     the protocol, an established  session  can  be  purely  request/re-
	     sponse-based  (like  HTTP),  exchange  data  in a bidirectional way
	     (like arbitrary TCP sessions), or just contain  a	single	datagram
	     and  an  optional	response  (like  UDP-based  protocols).  But the
	     client always requests to	communicate  with  a  remote  peer;  the
	     server.

     quick   If a connection is matched by a rule with the quick option set, the
	     rule  is  considered  to  be the last matching rule and any further
	     evaluation is skipped.

     inet or inet6
	     Only match connections with the specified address family, either of
	     type IPv4 or IPv6.

     from address[/prefix]
	     This rule only matches for connections from the specified source.

     to address[/prefix]
	     This rule only matches for connections to	the  specified	destina-
	     tion.  The destination is the address the client was connecting to,
	     typically	the  relay's listen address in non-transparent mode, not
	     the address of the forwarded backend connection.

     forward to <table>
	     Forward the request to a server in the specified table.  With  this
	     option, requests can be passed to specific backend servers.  A cor-
	     responding  forward  to  declaration in the "RELAYS" section is re-
	     quired.

     label string
	     The label will be printed as part	of  the  error	message  if  the
	     return error option is set and may contain HTML tags, for example:

		   block request url digest 5c1e03f58f8ce0b457474ffb371fd1ef \
			   label "<a href='http://example.com/adv.pl?id=7359'>\
			   Advisory provided by example.com</a>"

     no parameter
	     Reset  a  sticky  parameter  that	was previously set by a matching
	     rule.  The parameter is a keyword that can be either label or tag.

     tag string
	     Add a "sticky" tag to connections matching this filter rule.   Tags
	     can  be  used  to	filter the connection by further rules using the
	     tagged option.  Only one tag is assigned per  connection;	the  tag
	     will be replaced if the connection is already tagged.

     tagged string
	     Match  the connection if it is already tagged with a given tag by a
	     previous rule.

     The following parameters are available when using the http protocol:

     method name
	     Match the HTTP request method.  The method is specified by name and
	     can be either ACL, BASELINE-CONTROL,  CHECKIN,  CHECKOUT,	CONNECT,
	     COPY,  DELETE,  GET,  HEAD,  LABEL, LOCK, MERGE, MKACTIVITY, MKCOL,
	     MKREDIRECTREF, MKWORKSPACE, MOVE, OPTIONS, ORDERPATCH, PATCH, POST,
	     PROPFIND,	PROPPATCH,  PUT,  REPORT,  SEARCH,  TRACE,   UNCHECKOUT,
	     UNLOCK, UPDATE, UPDATEREDIRECTREF, or VERSION-CONTROL.

     type option [[digest] (key|file path) [value value]]
	     Match a specified HTTP header entity and an optional key and value.
	     An option can be specified to modify the matched entity or to trig-
	     ger an event.  The entity is extracted from the HTTP request or re-
	     sponse  header  and  can  be  either  of type cookie, header, path,
	     query, or url.

	     Instead of a single key, multiple keys can be loaded  from  a  file
	     specified	by  path  that contains one key per line.  Lines will be
	     stripped at the first whitespace or newline character and any empty
	     lines or lines beginning with a hash mark (`#') will be ignored.

	     If the digest keyword is specified, compare the message  digest  of
	     the  key  against the defined string.  The algorithm used is deter-
	     mined by the string length of the key  argument,  either  SHA1  (40
	     characters) or MD5 (32 characters).  To compute the digest, for ex-
	     ample for a url, use this simple command:

		   $ echo -n "example.com/path/?args" | sha1

     [type] may be one of:

     cookie option [key [value value]]
	     Look  up  the entity as a value in the Cookie header.  This type is
	     only available with the direction request.

     header option [key [value value]]
	     Look up the entity in the application protocol headers,  like  HTTP
	     headers in http mode.

     path option [key [value value]]
	     Look  up  the entity as a value in the URL path when using the http
	     protocol.	This type is only available with the direction	request.
	     The  key will match the path of the requested URL without the host-
	     name and query and the value will match the complete query, for ex-
	     ample:

		   block path "/index.html"
		   block path "/cgi-bin/t.cgi" value "foo=bar*"

     path strip number
	     Strip number path components from the beginning of the path of  the
	     requested	URL  when  using  the  http protocol.  This type is only
	     available with the direction request.

     query option [key [value value]]
	     Look up the entity as a query variable in the URL	when  using  the
	     http  protocol.   This  type  is  only available with the direction
	     request, for example:

		   # Will match /cgi-bin/example.pl?foo=bar&ok=yes
		   pass request query "foo" value "bar"

     url option [[digest] key [value value]]
	     Look up the entity as a URL suffix/prefix expression consisting  of
	     a	canonicalized hostname without port or suffix and a path name or
	     prefix when using the http protocol.  This type is  only  available
	     with the direction request, for example:

		   block url "example.com/index.html"
		   block url "example.com/test.cgi?val=1"

	     relayd(8)	will  match  the  full	URL  and different possible suf-
	     fix/prefix combinations by stripping subdomains and path components
	     (up to 5 levels), and the query string.  For example, the following
	     lookups	  will	    be	    done      for	http://www.exam-
	     ple.com:81/1/2/3/4/5.html?query=yes:

		   www.example.com/1/2/3/4/5.html?query=yes
		   www.example.com/1/2/3/4/5.html
		   www.example.com/
		   www.example.com/1/
		   www.example.com/1/2/
		   www.example.com/1/2/3/
		   example.com/1/2/3/4/5.html?query=yes
		   example.com/1/2/3/4/5.html
		   example.com/
		   example.com/1/
		   example.com/1/2/
		   example.com/1/2/3/

     [option] may be one of:

     append  Append  the  specified value to a protocol entity with the selected
	     key name.	If it does not exist, it will be created  with	the  new
	     value.

	     The  value  string  may  contain predefined macros that will be ex-
	     panded at runtime:

		   $HOST	 The Host header's value of the relay.
		   $REMOTE_ADDR  The IP address of the connected client.
		   $REMOTE_PORT  The TCP source port of the connected client.
		   $SERVER_ADDR  The configured IP address of the relay.
		   $SERVER_PORT  The configured TCP server port of the relay.
		   $SERVER_NAME  The server software name of relayd(8).
		   $TIMEOUT	 The configured session timeout of the relay.

     hash    Feed the value of the selected entity into the load balancing  hash
	     to  select  the target host.  See the table keyword in the "RELAYS"
	     section above.

     log     Log the key name and the value of the entity.

     remove  Remove the entity with the selected key name.

     set     Like the append directive above, but change  the  contents  of  the
	     specified entity.	If key does not exist in the request, it will be
	     created with the new value.

	     The  value  string  may  contain predefined macros that will be ex-
	     panded at runtime, as detailed for the append directive above.

FILES
     /usr/local/etc/relayd.conf 	       relayd(8) configuration file.

     /etc/examples/relayd.conf		       Example configuration file.

     /etc/services			       Service name database.

     /usr/local/etc/ssl/address.crt
     /usr/local/etc/ssl/address:port.crt
     /usr/local/etc/ssl/private/address.key
     /usr/local/etc/ssl/private/address:port.key
					       Location of the relay TLS  server
					       certificates,  where  address  is
					       the  configured	IP  address  and
					       port  is the configured port num-
					       ber of the relay.

     /usr/local/etc/ssl/cert.pem	       Default location of the CA bundle
					       that can be used with relayd(8).

EXAMPLES
     This configuration file would create a redirection service "www" which load
     balances four hosts and falls back to one host containing a "sorry page":

	   www1=front-www1.private.example.com
	   www2=front-www2.private.example.com
	   www3=front-www3.private.example.com
	   www4=front-www4.private.example.com

	   interval 5

	   table <phphosts> { $www1, $www2, $www3, $www4 }
	   table <sorryhost> disable { sorryhost.private.example.com }

	   redirect "www" {
		   listen on www.example.com port 8080 interface trunk0
		   listen on www6.example.com port 80 interface trunk0

		   pftag REDIRECTED

		   forward to <phphosts> port 8080 timeout 300 \
			   check http "/" digest "630aa3c2f..."
		   forward to <sorryhost> port 8080 timeout 300 check icmp
	   }

     It is possible to specify multiple listen directives with different IP pro-
     tocols in a single redirection configuration:

	   redirect "dns" {
		   listen on dns.example.com tcp port 53
		   listen on dns.example.com udp port 53

		   forward to <dnshosts> port 53 check tcp
	   }

     The following configuration would add a relay to forward secure HTTPS  con-
     nections  to  a pool of HTTP webservers using the loadbalance mode (TLS ac-
     celeration and layer 7 load balancing).  The HTTP protocol definition  will
     add  two  HTTP headers containing address information of the client and the
     server, set the "Keep-Alive" header value to the configured  session  time-
     out,  and include the "sessid" variable in the hash to calculate the target
     host:

	   http protocol "https" {
		   match header set "X-Forwarded-For" \
			   value "$REMOTE_ADDR"
		   match header set "X-Forwarded-By" \
			   value "$SERVER_ADDR:$SERVER_PORT"
		   match header set "Keep-Alive" value "$TIMEOUT"

		   match query hash "sessid"

		   pass
		   block path "/cgi-bin/index.cgi" value "*command=*"

		   tls { no tlsv1.0, ciphers "HIGH" }
	   }

	   relay "tlsaccel" {
		   listen on www.example.com port 443 tls
		   protocol "https"
		   forward to <phphosts> port 8080 mode loadbalance check tcp
	   }

     The second relay example will accept incoming connections to port 2222  and
     forward  them  to a remote SSH server.  The TCP nodelay option will allow a
     "smooth" SSH session without delays between keystrokes or displayed  output
     on the terminal:

	   protocol "myssh" {
		   tcp { nodelay, socket buffer 65536 }
	   }

	   relay "sshforward" {
		   listen on www.example.com port 2222
		   protocol "myssh"
		   forward to shell.example.com port 22
	   }

     The following relay example will configure "TLS inspection" as described in
     the  "TLS RELAYS" section.  To start, first generate a new local CA key and
     certificate:

	   # openssl req -x509 -days 365 -newkey rsa:2048 \
		   -keyout /usr/local/etc/ssl/private/ca.key \
		   -out /usr/local/etc/etc/ssl/ca.crt

     A TLS server key and self-signed cert for 127.0.0.1 are also required;  see
     listen  on in the "RELAYS" section for more details about certificate loca-
     tions.  Configure	the  packet  filter  with  a  matching	divert	rule  in
     pf.conf(5):

	   # Divert incoming HTTPS traffic to relayd
	   pass in on vlan1 inet proto tcp to port 443 \
		   divert-to localhost port 8443

     And finally configure the TLS inspection in relayd.conf:

	   http protocol httpfilter {
		   return error

		   pass
		   match label "Prohibited!"
		   block url "social.network.example.com/"

		   # New configuration directives for TLS Interception
		   tls ca key "/etc/ssl/private/ca.key" password "password123"
		   tls ca cert "/etc/ssl/ca.crt"
	   }

	   relay tlsinspect {
		   listen on 127.0.0.1 port 8443 tls
		   protocol httpfilter
		   forward with tls to destination
	   }

     The  next simple router configuration example can be used to run redundant,
     health-checked WAN links:

	   table <gateways> { $gw1 ip ttl 1, $gw2 ip ttl 1 }
	   router "uplinks" {
		   route 0.0.0.0/0
		   forward to <gateways> check icmp
	   }

SEE ALSO
     ocspcheck(8), relayctl(8), relayd(8), ssl(8)

HISTORY
     The relayd.conf file format, formerly known as hoststated.conf,  first  ap-
     peared in OpenBSD 4.1.  It was renamed to relayd.conf in OpenBSD 4.3.

AUTHORS
     The    relayd(8)	 program    was   written   by	 Pierre-Yves   Ritschard
     <pyr@openbsd.org> and Reyk Floeter <reyk@openbsd.org>.

CAVEATS
     relayd(8) verification of TLS server certificates is based on a  static  CA
     bundle  and  relayd(8) currently does not support CRLs (Certificate Revoca-
     tion Lists).

FreeBSD ports 15.quarterly	October 29, 2023		  RELAYD.CONF(5)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=relayd.conf&sektion=5&manpath=FreeBSD+Ports+15.1.quarterly>

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