1# libcoap: A C implementation of the Constrained Application Protocol (RFC 7252) 2 3[](https://github.com/obgm/libcoap/actions?query=branch:main) 4[](https://github.com/obgm/libcoap/actions?query=branch:develop) 5[](https://scan.coverity.com/projects/obgm-libcoap) 6[](https://bugs.chromium.org/p/oss-fuzz/issues/list?sort=-opened&can=1&q=proj:libcoap) 7[](https://github.com/obgm/libcoap/actions/workflows/cifuzz.yml) 8[](https://github.com/pre-commit/pre-commit) 9 10Copyright (C) 2010—2023 by Olaf Bergmann <bergmann@tzi.org> and others 11 12ABOUT LIBCOAP 13============= 14 15libcoap is a C implementation of a lightweight application-protocol 16for devices that are constrained their resources such as computing 17power, RF range, memory, bandwidth, or network packet sizes. This 18protocol, CoAP, is standardized by the IETF as RFC 7252. For further 19information related to CoAP, see <https://coap.space> or 20[CoAP Wiki](https://en.wikipedia.org/wiki/Constrained_Application_Protocol). 21 22You might want to check out 23[libcoap-minimal](https://github.com/obgm/libcoap-minimal) for usage 24examples. 25 26DOCUMENTATION 27============= 28 29Documentation and further information can be found at 30<https://libcoap.net>. 31 32PACKAGE CONTENTS 33================ 34 35This package contains a protocol parser and basic networking 36functions for platforms with support for malloc() and BSD-style 37sockets. In addition, there is support for Contiki-NG, 38Espressif/ESP-IDF, LwIP and RIOT-OS hosted environments. 39 40The following RFCs are supported 41 42* [RFC7252: The Constrained Application Protocol (CoAP)](https://rfc-editor.org/rfc/rfc7252) 43 44* [RFC7390: Group Communication for the Constrained Application Protocol (CoAP)](https://rfc-editor.org/rfc/rfc7390) 45 46* [RFC7641: Observing Resources in the Constrained Application Protocol (CoAP)](https://rfc-editor.org/rfc/rfc7641) 47 48* [RFC7959: Block-Wise Transfers in the Constrained Application Protocol (CoAP)](https://rfc-editor.org/rfc/rfc7959) 49 50* [RFC7967: Constrained Application Protocol (CoAP) Option for No Server Response](https://rfc-editor.org/rfc/rfc7967) 51 52* [RFC8132: PATCH and FETCH Methods for the Constrained Application Protocol (CoAP)](https://rfc-editor.org/rfc/rfc8132) 53 54* [RFC8323: CoAP (Constrained Application Protocol) over TCP, TLS, and WebSockets](https://rfc-editor.org/rfc/rfc8323) 55 56* [RFC8516: "Too Many Requests" Response Code for the Constrained Application Protocol](https://rfc-editor.org/rfc/rfc8516) 57 58* [RFC8613: Object Security for Constrained RESTful Environments (OSCORE)](https://rfc-editor.org/rfc/rfc8613) 59 60* [RFC8768: Constrained Application Protocol (CoAP) Hop-Limit Option](https://rfc-editor.org/rfc/rfc8768) 61 62* [RFC8974: Extended Tokens and Stateless Clients in the Constrained Application Protocol (CoAP)](https://rfc-editor.org/rfc/rfc8974) 63 64* [RFC9175: CoAP: Echo, Request-Tag, and Token Processing](https://rfc-editor.org/rfc/rfc9175) 65 66* [RFC9177: Constrained Application Protocol (CoAP) Block-Wise Transfer Options Supporting Robust Transmission](https://rfc-editor.org/rfc/rfc9177) 67 68There is (D)TLS support for the following libraries 69 70* [OpenSSL](https://www.openssl.org) (Minimum version 1.1.0) [PKI, PSK and PKCS11] 71 72* [GnuTLS](https://www.gnutls.org) (Minimum version 3.3.0) [PKI, PSK, RPK(3.6.6+) and PKCS11] 73 74* [Mbed TLS](https://www.trustedfirmware.org/projects/mbed-tls/) (Minimum version 2.7.10) [PKI and PSK] 75 76* [TinyDTLS](https://github.com/eclipse/tinydtls) [PSK and RPK] [DTLS Only] 77 78The examples directory contain a CoAP client, CoAP Resource Directory server 79and a CoAP server to demonstrate the use of this library. 80 81BUILDING 82======== 83 84Further information can be found at <https://libcoap.net/install.html> 85and [BUILDING](https://raw.githubusercontent.com/obgm/libcoap/develop/BUILDING). 86 87LICENSE INFORMATION 88=================== 89 90This library is published as open-source software without any warranty 91of any kind. Use is permitted under the terms of the simplified BSD 92license. It includes public domain software. libcoap binaries may also 93include open-source software with their respective licensing terms. 94Please refer to 95[LICENSE](https://raw.githubusercontent.com/obgm/libcoap/develop/LICENSE) 96for further details. 97 98
