NAME
coap-server, coap-server-gnutls, coap-server-mbedtls, coap-server-openssl, coap-server-notls — CoAP Server based on libcoap
SYNOPSIS
coap-server [-a priority] [-b max_block_size] [-d max] [-e]
[-f scheme://addr[:port]
[-g group] [-l loss] [-p port] [-q tls_engine_conf_file]
[-r] [-t] [-v num] [-w [port][,secure_port]] [-x]
[-A address] [-E oscore_conf_file[,seq_file]]
[-G group_if] [-L value] [-N]
[-P scheme://addr[:port],[name1[,name2..]]]
[-T max_token_size] [-U type] [-V num] [-X size]
[[-h hint] [-i match_identity_file] [-k key]
[-s match_psk_sni_file] [-u user] [-2]]
[[-c certfile] [-j keyfile] [-n] [-C cafile]
[-J pkcs11_pin] [-M rpk_file] [-R trust_casfile]
[-S match_pki_sni_file]]
For coap-server versions that use libcoap compiled for different
(D)TLS libraries, coap-server-notls, coap-server-gnutls,
coap-server-openssl, coap-server-mbedtls or coap-server-tinydtls may be
available. Otherwise, coap-server uses the default libcoap (D)TLS support.
DESCRIPTION
coap-server is an example server for the 'Constrained Application Protocol`
(RFC 7252).
OPTIONS - General
-
-a priority
-
Send logging output to syslog at priority (0-7) level.
-
-b max_block_size
-
Maximum block size server supports (16, 32, 64, 128, 256, 512 or 1024) in
bytes.
-
-d max
-
Enable support for creation of dynamic resources when doing a PUT up to a
limit of max. If max is reached, a 4.06 code is returned until one of
the dynamic resources has been deleted.
-
-e
-
Echo back the data sent with a PUT.
-
-f scheme://address[:port]
-
Act as a reverse proxy where scheme, address, optional
port define how to connect to the internal server.
Scheme is one of coap, coaps, coap+tcp, coaps+tcp,
coap+ws, and coaps+ws. http(s) is not currently supported.
This option can be repeated to provide multiple internal
servers that are round-robin load balanced.
-
-g group
-
Join specified multicast group on start up.
Note: DTLS over multicast is not currently supported.
-
-l list
-
Fail to send some datagrams specified by a comma separated list of
numbers or number ranges (debugging only).
-
-l loss%
-
Randomly failed to send datagrams with the specified probability - 100%
all datagrams, 0% no datagrams (debugging only).
-
-p port
-
The port on the given address will be listening for incoming connections.
If (D)TLS is supported, then port + 1 will also be listened on for
(D)TLS connections.
The default port is 5683 if not given any other value.
-
-q tls_engine_conf_file
-
tls_engine_conf_file contains TLS ENGINE configuration. Only OpenSSL
is currently supported.
See coap-tls-engine-conf(5) for definitions.
-
-r
-
Enable multicast per resource support. If enabled, only /, /async
and /.well-known/core are enabled for multicast requests support,
otherwise all resources are enabled.
-
-t
-
Track resource’s observe values so observe subscriptions can be
maintained over a server restart.
Note: Use kill SIGUSR2 <pid> for controlled shutdown.
-
-v num
-
The verbosity level to use (default 4, maximum is 8) for general
CoAP logging.
-
-w [port][,secure_port]
-
Enable WebSockets support support on port (WS) and/or secure_port (WSS),
comma separated.
-
-x
-
Disable output of PDU data when displaying PDUs.
-
-A address
-
The local address of the interface which the server has to listen on.
-
-E oscore_conf_file[,seq_file]
-
oscore_conf_file contains OSCORE configuration. See coap-oscore-conf(5)
for definitions. Optional seq_file (which is created if needed) is used to
save the current transmit sequence number, so on server restart sequence
numbers continue to increase and are not reset to prevent anti-replay
mechanisms being triggered.
-
-G group_if
-
Use this interface for listening for the multicast group. This can be
different from the implied interface if the -A option is used.
-
-L value
Sum of one or more COAP_BLOCK_* flag values for different block handling
methods. Default is 1 (COAP_BLOCK_USE_LIBCOAP).
COAP_BLOCK_USE_LIBCOAP 1
COAP_BLOCK_SINGLE_BODY 2
COAP_BLOCK_TRY_Q_BLOCK 4
COAP_BLOCK_STLESS_BLOCK2 64
COAP_BLOCK_NOT_RANDOM_BLOCK1 128
-
-N
-
Send NON-confirmable message for "observe" responses. If option -N is
not specified, a confirmable response will be sent. Even if set, every
fifth response will still be sent as a confirmable response
(RFC 7641 requirement).
-
-P scheme://address[:port],[name1[,name2[,name3..]]]
-
Scheme, address, optional port of how to connect to the next proxy server
and zero or more names (comma separated) that this proxy server is known by.
The , (comma) is required. If there is no name1 or
if the hostname of the incoming proxy request matches one of these names,
then this server is considered to be the final endpoint. If
scheme://address[:port] is not defined before the leading , (comma) of the
first name, then the ongoing connection will be a direct connection.
Scheme is one of coap, coaps, coap+tcp, coaps+tcp, coap+ws, and coaps+ws.
http and https not currently supported.
This option can be repeated to provide multiple upstream
servers that are round-robin load balanced.
-
-T max_token_size
-
Set the maximum token length (8-65804).
-
-U type
-
Treat address defined by -A as a Unix socket address.
Type is coap (using datagram), coap+tcp (using stream), coaps
(DTLS using datagram) or coaps+tcp (TLS using stream).
-
-V num
-
The verbosity level to use (default 3, maximum is 7) for (D)TLS
library logging.
-
-X size
-
Maximum message size to use for TCP based connections (default is 8388864).
Maximum value of 2^32 -1.
OPTIONS - PSK
(If supported by underlying (D)TLS library)
-
-h hint
-
Identity Hint to send. Default is CoAP. Zero length is no hint.
-
-i match_identiity_file
-
This is a file that contains one or more lines of Identity Hints and (user)
Identities to match for a different new Pre-Shared Key (PSK) (comma
separated) to be used. E.g., per line
hint_to_match,identity_to_match,use_key
A line that starts with # is treated as a comment.
Note: -k still needs to be defined for the default case.
Note: A match using the -s option may mean that the current Identity Hint
is different to that defined by -h.
-
-k key
-
Pre-shared key to use for inbound connections. This cannot be empty if
defined.
If the key begins with 0x, then the hex text (two [0-9a-f] per byte) is
converted to binary data.
Note: if -c cafile is defined, you need to define -k key as well to
have the server support both PSK and PKI.
-
-s match_psk_sni_file
-
This is a file that contains one or more lines of received Subject Name
Identifier (SNI) to match to use a different Identity Hint and associated
Pre-Shared Key (PSK) (comma separated) instead of the -h hint and
-k key options. E.g., per line
sni_to_match,use_hint,with_key
Note: -k key still needs to be defined for the default case if there is
not a match.
Note: The associated Pre-Shared Key will get updated if there is also a -i
match. The update checking order is -s followed by -i.
-
-u user
-
User identity for pre-shared key mode (only used if option -P is set).
-
-2
-
Use EC-JPAKE negotiation (if supported).
OPTIONS - PKI
(If supported by underlying (D)TLS library)
Note: If any one of certfile, keyfile or cafile is in PKCS11 URI
naming format (pkcs11: prefix), then any remaining non PKCS11 URI file
definitions have to be in DER, not PEM, format. Otherwise all of
certfile, keyfile or cafile are in PEM format.
-
-c certfile
-
PEM file or PKCS11 URI for the certificate. The private key can also be in
the PEM file, or has the same PKCS11 URI. If not, the private key is defined
by -j keyfile.
Note: if -k key is defined, you need to define -c certfile as well to
have the server support both PSK and PKI.
-
-j keyfile
-
PEM file or PKCS11 URI for the private key for the certificate in -c
certfile if the parameter is different from certfile in -c certfile.
-
-n
-
Disable remote peer certificate checking. This gives clients the ability to
use PKI, but without any defined certificates.
-
-C cafile
-
PEM file or PKCS11 URI that contains a list of one or more CAs that are to
be passed to the client for the client to determine what client certificate
to use. Normally, this list of CAs would be the root CA and any
intermediate CAs. Ideally the server certificate should be signed by the
same CA so that mutual authentication can take place. The contents of
cafile are added to the trusted store of root CAs. Using the -C or -R
options will trigger the validation of the client certificate unless
overridden by the -n option.
-
-J pkcs11_pin
-
The user pin to unlock access to the PKCS11 token.
-
-M
-
Raw Public Key (RPK) PEM file or PKCS11 URI that contains both PUBLIC KEY
and PRIVATE KEY or just EC PRIVATE KEY. (GnuTLS and TinyDTLS(PEM) support
only). -C cafile or -R trust_casfile are not required.
-
-R trust_casfile
-
PEM file containing the set of trusted root CAs that are to be used to
validate the client certificate. Alternatively, this can point to a
directory containing a set of CA PEM files. The -C cafile CA does not have
to be in this list and is trusted for the validation. Using
-R trust_casfile disables common CA mutual authentication which can only
be done by using -C cafile. Using the -C or -R options will
trigger the validation of the client certificate unless overridden by the
-n option.
-
-S match_pki_sni_file
-
This option denotes a file that contains one or more lines of Subject Name
Identifier (SNI) to match for new certificate File and new CA File (comma
separated) to be used. E.g., entry per line
sni_to_match,new_cert_file,new_ca_file
A line that starts with # is treated as a comment.
Note: -c certfile and -C cafile still needs to be defined for the
default case
EXAMPLES
coap-server -A ::1
Let the server listen on localhost (port 5683) for UDP/TCP.
coap-server -A ::1 -k mysecretKey -h myhint
Let the server listen on localhost (port 5683 for UDP/TCP and port 5684 for
DTLS/TLS) with the server set up for PSK authentication if the client uses
coaps:// or coaps+tcp://.
coap-server -A ::1 -k mysecretKey -h myhint -p 13011
The same, except the UDP/TCP listening port is 13011 and the DTLS/TLS
listening port is 13012 (and not the default ports 5683 and 5684).
coap-server -A 2001:db8:81a8:0:6ef0:dead:feed:beef -v 5
The listening address is set to 2001:db8:81a8:0:6ef0:dead:feed:beef and the
verbosity level is set to 5.
coap-server -A 2001:db8:81a8:0:6ef0:dead:feed:beef -g FF02::FD
Set listening address to 2001:db8:81a8:0:6ef0:dead:feed:beef and join the
All CoAP Nodes multicast group FF02::FD.
coap-server -P, -A ::1
Let the server listen on localhost (port 5683) for UDP/TCP, as well as
accept any CoAP proxy requests and directly respond to them.
coap-server -P coap://upstream-proxy, -A ::1
Let the server listen on localhost (port 5683) for UDP/TCP, and then
open an upstream coap session to upstream-proxy for proxying onwards
the CoAP client’s request.
FILES
There are no configuration files.
EXIT STATUS
-
0
-
Success
-
1
-
Failure (syntax or usage error; configuration error; document
processing failure; unexpected error)
1.9.4