pdu.h
Go to the documentation of this file.
/*
* pdu.h -- CoAP message structure
*
* Copyright (C) 2010-2014 Olaf Bergmann <bergmann@tzi.org>
*
* This file is part of the CoAP library libcoap. Please see README for terms
* of use.
*/
#ifndef COAP_PDU_H_
#define COAP_PDU_H_
#include "uri.h"
struct coap_session_t;
#ifdef WITH_LWIP
#include <lwip/pbuf.h>
#endif
#include <stdint.h>
#define COAP_DEFAULT_PORT 5683 /* CoAP default UDP/TCP port */
#define COAPS_DEFAULT_PORT 5684 /* CoAP default UDP/TCP port for secure transmission */
#define COAP_DEFAULT_MAX_AGE 60 /* default maximum object lifetime in seconds */
#ifndef COAP_DEFAULT_MTU
#define COAP_DEFAULT_MTU 1152
#endif /* COAP_DEFAULT_MTU */
/* TCP Message format constants, do not modify */
#define COAP_MESSAGE_SIZE_OFFSET_TCP8 13
#define COAP_MESSAGE_SIZE_OFFSET_TCP16 269 /* 13 + 256 */
#define COAP_MESSAGE_SIZE_OFFSET_TCP32 65805 /* 269 + 65536 */
/* Derived message size limits */
#define COAP_MAX_MESSAGE_SIZE_TCP0 (COAP_MESSAGE_SIZE_OFFSET_TCP8-1) /* 12 */
#define COAP_MAX_MESSAGE_SIZE_TCP8 (COAP_MESSAGE_SIZE_OFFSET_TCP16-1) /* 268 */
#define COAP_MAX_MESSAGE_SIZE_TCP16 (COAP_MESSAGE_SIZE_OFFSET_TCP32-1) /* 65804 */
#define COAP_MAX_MESSAGE_SIZE_TCP32 (COAP_MESSAGE_SIZE_OFFSET_TCP32+0xFFFFFFFF)
#ifndef COAP_DEFAULT_MAX_PDU_RX_SIZE
#if defined(WITH_CONTIKI) || defined(WITH_LWIP)
#define COAP_DEFAULT_MAX_PDU_RX_SIZE (COAP_MAX_MESSAGE_SIZE_TCP16+4)
#else
/* 8 MiB max-message-size plus some space for options */
#define COAP_DEFAULT_MAX_PDU_RX_SIZE (8*1024*1024+256)
#endif
#endif /* COAP_DEFAULT_MAX_PDU_RX_SIZE */
#ifndef COAP_DEBUG_BUF_SIZE
#if defined(WITH_CONTIKI) || defined(WITH_LWIP)
#define COAP_DEBUG_BUF_SIZE 128
#else /* defined(WITH_CONTIKI) || defined(WITH_LWIP) */
/* 1024 derived from RFC7252 4.6. Message Size max payload */
#define COAP_DEBUG_BUF_SIZE (8 + 1024 * 2)
#endif /* defined(WITH_CONTIKI) || defined(WITH_LWIP) */
#endif /* COAP_DEBUG_BUF_SIZE */
#define COAP_DEFAULT_VERSION 1 /* version of CoAP supported */
#define COAP_DEFAULT_SCHEME "coap" /* the default scheme for CoAP URIs */
#define COAP_DEFAULT_URI_WELLKNOWN ".well-known/core"
/* CoAP message types */
#define COAP_MESSAGE_CON 0 /* confirmable message (requires ACK/RST) */
#define COAP_MESSAGE_NON 1 /* non-confirmable message (one-shot message) */
#define COAP_MESSAGE_ACK 2 /* used to acknowledge confirmable messages */
#define COAP_MESSAGE_RST 3 /* indicates error in received messages */
/* CoAP request methods */
#define COAP_REQUEST_GET 1
#define COAP_REQUEST_POST 2
#define COAP_REQUEST_PUT 3
#define COAP_REQUEST_DELETE 4
#define COAP_REQUEST_FETCH 5 /* RFC 8132 */
#define COAP_REQUEST_PATCH 6 /* RFC 8132 */
#define COAP_REQUEST_IPATCH 7 /* RFC 8132 */
/*
* CoAP option types (be sure to update coap_option_check_critical() when
* adding options
*/
#define COAP_OPTION_IF_MATCH 1 /* C, opaque, 0-8 B, (none) */
#define COAP_OPTION_URI_HOST 3 /* C, String, 1-255 B, destination address */
#define COAP_OPTION_ETAG 4 /* E, opaque, 1-8 B, (none) */
#define COAP_OPTION_IF_NONE_MATCH 5 /* empty, 0 B, (none) */
#define COAP_OPTION_URI_PORT 7 /* C, uint, 0-2 B, destination port */
#define COAP_OPTION_LOCATION_PATH 8 /* E, String, 0-255 B, - */
#define COAP_OPTION_URI_PATH 11 /* C, String, 0-255 B, (none) */
#define COAP_OPTION_CONTENT_FORMAT 12 /* E, uint, 0-2 B, (none) */
#define COAP_OPTION_CONTENT_TYPE COAP_OPTION_CONTENT_FORMAT
#define COAP_OPTION_MAXAGE 14 /* E, uint, 0--4 B, 60 Seconds */
#define COAP_OPTION_URI_QUERY 15 /* C, String, 1-255 B, (none) */
#define COAP_OPTION_ACCEPT 17 /* C, uint, 0-2 B, (none) */
#define COAP_OPTION_LOCATION_QUERY 20 /* E, String, 0-255 B, (none) */
#define COAP_OPTION_SIZE2 28 /* E, uint, 0-4 B, (none) */
#define COAP_OPTION_PROXY_URI 35 /* C, String, 1-1034 B, (none) */
#define COAP_OPTION_PROXY_SCHEME 39 /* C, String, 1-255 B, (none) */
#define COAP_OPTION_SIZE1 60 /* E, uint, 0-4 B, (none) */
/* option types from RFC 7641 */
#define COAP_OPTION_OBSERVE 6 /* E, empty/uint, 0 B/0-3 B, (none) */
#define COAP_OPTION_SUBSCRIPTION COAP_OPTION_OBSERVE
/* selected option types from RFC 7959 */
#define COAP_OPTION_BLOCK2 23 /* C, uint, 0--3 B, (none) */
#define COAP_OPTION_BLOCK1 27 /* C, uint, 0--3 B, (none) */
/* selected option types from RFC 7967 */
#define COAP_OPTION_NORESPONSE 258 /* N, uint, 0--1 B, 0 */
#define COAP_MAX_OPT 65535
/* CoAP result codes (HTTP-Code / 100 * 40 + HTTP-Code % 100) */
/* As of draft-ietf-core-coap-04, response codes are encoded to base
* 32, i.e. the three upper bits determine the response class while
* the remaining five fine-grained information specific to that class.
*/
#define COAP_RESPONSE_CODE(N) (((N)/100 << 5) | (N)%100)
/* Determines the class of response code C */
#define COAP_RESPONSE_CLASS(C) (((C) >> 5) & 0xFF)
#ifndef SHORT_ERROR_RESPONSE
const char *coap_response_phrase(unsigned char code);
#define COAP_ERROR_PHRASE_LENGTH 32
#else
#define coap_response_phrase(x) ((char *)NULL)
#define COAP_ERROR_PHRASE_LENGTH 0
#endif /* SHORT_ERROR_RESPONSE */
/* The following definitions exist for backwards compatibility */
#if 0 /* this does not exist any more */
#define COAP_RESPONSE_100 40 /* 100 Continue */
#endif
#define COAP_RESPONSE_200 COAP_RESPONSE_CODE(200) /* 2.00 OK */
#define COAP_RESPONSE_201 COAP_RESPONSE_CODE(201) /* 2.01 Created */
#define COAP_RESPONSE_304 COAP_RESPONSE_CODE(203) /* 2.03 Valid */
#define COAP_RESPONSE_400 COAP_RESPONSE_CODE(400) /* 4.00 Bad Request */
#define COAP_RESPONSE_404 COAP_RESPONSE_CODE(404) /* 4.04 Not Found */
#define COAP_RESPONSE_405 COAP_RESPONSE_CODE(405) /* 4.05 Method Not Allowed */
#define COAP_RESPONSE_415 COAP_RESPONSE_CODE(415) /* 4.15 Unsupported Media Type */
#define COAP_RESPONSE_500 COAP_RESPONSE_CODE(500) /* 5.00 Internal Server Error */
#define COAP_RESPONSE_501 COAP_RESPONSE_CODE(501) /* 5.01 Not Implemented */
#define COAP_RESPONSE_503 COAP_RESPONSE_CODE(503) /* 5.03 Service Unavailable */
#define COAP_RESPONSE_504 COAP_RESPONSE_CODE(504) /* 5.04 Gateway Timeout */
#if 0 /* these response codes do not have a valid code any more */
# define COAP_RESPONSE_X_240 240 /* Token Option required by server */
# define COAP_RESPONSE_X_241 241 /* Uri-Authority Option required by server */
#endif
#define COAP_RESPONSE_X_242 COAP_RESPONSE_CODE(402) /* Critical Option not supported */
#define COAP_SIGNALING_CODE(N) (((N)/100 << 5) | (N)%100)
#define COAP_SIGNALING_CSM COAP_SIGNALING_CODE(701)
#define COAP_SIGNALING_PING COAP_SIGNALING_CODE(702)
#define COAP_SIGNALING_PONG COAP_SIGNALING_CODE(703)
#define COAP_SIGNALING_RELEASE COAP_SIGNALING_CODE(704)
#define COAP_SIGNALING_ABORT COAP_SIGNALING_CODE(705)
/* Applies to COAP_SIGNALING_CSM */
#define COAP_SIGNALING_OPTION_MAX_MESSAGE_SIZE 2
#define COAP_SIGNALING_OPTION_BLOCK_WISE_TRANSFER 4
/* Applies to COAP_SIGNALING_PING / COAP_SIGNALING_PONG */
#define COAP_SIGNALING_OPTION_CUSTODY 2
/* Applies to COAP_SIGNALING_RELEASE */
#define COAP_SIGNALING_OPTION_ALTERNATIVE_ADDRESS 2
#define COAP_SIGNALING_OPTION_HOLD_OFF 4
/* Applies to COAP_SIGNALING_ABORT */
#define COAP_SIGNALING_OPTION_BAD_CSM_OPTION 2
/* CoAP media type encoding */
#define COAP_MEDIATYPE_TEXT_PLAIN 0 /* text/plain (UTF-8) */
#define COAP_MEDIATYPE_APPLICATION_LINK_FORMAT 40 /* application/link-format */
#define COAP_MEDIATYPE_APPLICATION_XML 41 /* application/xml */
#define COAP_MEDIATYPE_APPLICATION_OCTET_STREAM 42 /* application/octet-stream */
#define COAP_MEDIATYPE_APPLICATION_RDF_XML 43 /* application/rdf+xml */
#define COAP_MEDIATYPE_APPLICATION_EXI 47 /* application/exi */
#define COAP_MEDIATYPE_APPLICATION_JSON 50 /* application/json */
#define COAP_MEDIATYPE_APPLICATION_CBOR 60 /* application/cbor */
/* Content formats from RFC 8152 */
#define COAP_MEDIATYPE_APPLICATION_COSE_SIGN 98 /* application/cose; cose-type="cose-sign" */
#define COAP_MEDIATYPE_APPLICATION_COSE_SIGN1 18 /* application/cose; cose-type="cose-sign1" */
#define COAP_MEDIATYPE_APPLICATION_COSE_ENCRYPT 96 /* application/cose; cose-type="cose-encrypt" */
#define COAP_MEDIATYPE_APPLICATION_COSE_ENCRYPT0 16 /* application/cose; cose-type="cose-encrypt0" */
#define COAP_MEDIATYPE_APPLICATION_COSE_MAC 97 /* application/cose; cose-type="cose-mac" */
#define COAP_MEDIATYPE_APPLICATION_COSE_MAC0 17 /* application/cose; cose-type="cose-mac0" */
#define COAP_MEDIATYPE_APPLICATION_COSE_KEY 101 /* application/cose-key */
#define COAP_MEDIATYPE_APPLICATION_COSE_KEY_SET 102 /* application/cose-key-set */
/* Content formats from RFC 8428 */
#define COAP_MEDIATYPE_APPLICATION_SENML_JSON 110 /* application/senml+json */
#define COAP_MEDIATYPE_APPLICATION_SENSML_JSON 111 /* application/sensml+json */
#define COAP_MEDIATYPE_APPLICATION_SENML_CBOR 112 /* application/senml+cbor */
#define COAP_MEDIATYPE_APPLICATION_SENSML_CBOR 113 /* application/sensml+cbor */
#define COAP_MEDIATYPE_APPLICATION_SENML_EXI 114 /* application/senml-exi */
#define COAP_MEDIATYPE_APPLICATION_SENSML_EXI 115 /* application/sensml-exi */
#define COAP_MEDIATYPE_APPLICATION_SENML_XML 310 /* application/senml+xml */
#define COAP_MEDIATYPE_APPLICATION_SENSML_XML 311 /* application/sensml+xml */
/* Note that identifiers for registered media types are in the range 0-65535. We
* use an unallocated type here and hope for the best. */
#define COAP_MEDIATYPE_ANY 0xff /* any media type */
typedef int coap_tid_t;
#define COAP_INVALID_TID -1
#define COAP_DROPPED_RESPONSE -2
#define COAP_PDU_DELAYED -3
#define COAP_OPT_LONG 0x0F /* OC == 0b1111 indicates that the option list
* in a CoAP message is limited by 0b11110000
* marker */
#define COAP_OPT_END 0xF0 /* end marker */
#define COAP_PAYLOAD_START 0xFF /* payload marker */
COAP_DEPRECATED typedef struct {
uint16_t key; /* the option key (no delta coding) */
unsigned int length;
} coap_option;
#define COAP_OPTION_KEY(option) (option).key
#define COAP_OPTION_LENGTH(option) (option).length
#define COAP_OPTION_DATA(option) ((unsigned char *)&(option) + sizeof(coap_option))
typedef struct coap_pdu_t {
uint8_t type;
uint8_t code;
uint8_t max_hdr_size;
uint8_t hdr_size;
uint8_t token_length;
uint16_t tid;
uint16_t max_delta;
size_t alloc_size;
size_t used_size;
size_t max_size;
uint8_t *token;
uint8_t *data;
#ifdef WITH_LWIP
struct pbuf *pbuf;
#endif
} coap_pdu_t;
#define COAP_PDU_IS_EMPTY(pdu) ((pdu)->code == 0)
#define COAP_PDU_IS_REQUEST(pdu) (!COAP_PDU_IS_EMPTY(pdu) && (pdu)->code < 32)
#define COAP_PDU_IS_RESPONSE(pdu) ((pdu)->code >= 64 && (pdu)->code < 224)
#define COAP_PDU_IS_SIGNALING(pdu) ((pdu)->code >= 224)
#define COAP_PDU_MAX_UDP_HEADER_SIZE 4
#define COAP_PDU_MAX_TCP_HEADER_SIZE 6
#ifdef WITH_LWIP
coap_pdu_t * coap_pdu_from_pbuf(struct pbuf *pbuf);
#endif
typedef uint8_t coap_proto_t;
#define COAP_PROTO_NONE 0
#define COAP_PROTO_UDP 1
#define COAP_PROTO_DTLS 2
#define COAP_PROTO_TCP 3
#define COAP_PROTO_TLS 4
coap_pdu_t *
coap_pdu_init(uint8_t type, uint8_t code, uint16_t tid, size_t size);
int coap_pdu_resize(coap_pdu_t *pdu, size_t new_size);
void coap_pdu_clear(coap_pdu_t *pdu, size_t size);
coap_pdu_t *coap_new_pdu(const struct coap_session_t *session);
void coap_delete_pdu(coap_pdu_t *);
size_t coap_pdu_parse_header_size(coap_proto_t proto,
const uint8_t *data);
size_t coap_pdu_parse_size(coap_proto_t proto,
const uint8_t *data,
size_t length);
int coap_pdu_parse_header(coap_pdu_t *pdu, coap_proto_t proto);
int coap_pdu_parse_opt(coap_pdu_t *pdu);
int coap_pdu_parse(coap_proto_t proto,
const uint8_t *data,
size_t length,
coap_pdu_t *pdu);
int coap_add_token(coap_pdu_t *pdu,
size_t len,
const uint8_t *data);
size_t coap_add_option(coap_pdu_t *pdu,
uint16_t type,
size_t len,
const uint8_t *data);
uint8_t *coap_add_option_later(coap_pdu_t *pdu,
uint16_t type,
size_t len);
int coap_add_data(coap_pdu_t *pdu,
size_t len,
const uint8_t *data);
uint8_t *coap_add_data_after(coap_pdu_t *pdu, size_t len);
int coap_get_data(const coap_pdu_t *pdu,
size_t *len,
uint8_t **data);
size_t coap_pdu_encode_header(coap_pdu_t *pdu, coap_proto_t proto);
#endif /* COAP_PDU_H_ */
coap_pdu_t::type
uint8_t type
message type
Definition: pdu.h:288
coap_pdu_t::code
uint8_t code
request method (value 1–10) or response code (value 40-255)
Definition: pdu.h:289
coap_option
Definition: pdu.h:266
coap_response_phrase
const char * coap_response_phrase(unsigned char code)
Returns a human-readable response phrase for the specified CoAP response code.
Definition: pdu.c:370
coap_session_t
Definition: coap_session.h:59
coap_pdu_clear
void coap_pdu_clear(coap_pdu_t *pdu, size_t size)
Clears any contents from pdu and resets used_size, and data pointers.
Definition: pdu.c:34
coap_proto_t
uint8_t coap_proto_t
Definition: pdu.h:339
coap_pdu_parse_size
size_t coap_pdu_parse_size(coap_proto_t proto, const uint8_t *data, size_t length)
Parses data to extract the message size.
Definition: pdu.c:428
coap_add_token
int coap_add_token(coap_pdu_t *pdu, size_t len, const uint8_t *data)
Adds token of length len to pdu.
Definition: pdu.c:191
coap_add_option_later
uint8_t * coap_add_option_later(coap_pdu_t *pdu, uint16_t type, size_t len)
Adds option of given type to pdu that is passed as first parameter, but does not write a value...
Definition: pdu.c:252
coap_new_pdu
coap_pdu_t * coap_new_pdu(const struct coap_session_t *session)
Creates a new CoAP PDU.
Definition: pdu.c:119
coap_tid_t
int coap_tid_t
coap_tid_t is used to store CoAP transaction id, i.e.
Definition: pdu.h:238
coap_option::length
unsigned int length
Definition: pdu.h:268
uri.h
coap_pdu_parse
int coap_pdu_parse(coap_proto_t proto, const uint8_t *data, size_t length, coap_pdu_t *pdu)
Parses data into the CoAP PDU structure given in result.
Definition: pdu.c:543
coap_add_data
int coap_add_data(coap_pdu_t *pdu, size_t len, const uint8_t *data)
Adds given data to the pdu that is passed as first parameter.
Definition: pdu.c:288
coap_add_option
size_t coap_add_option(coap_pdu_t *pdu, uint16_t type, size_t len, const uint8_t *data)
Adds option of given type to pdu that is passed as first parameter.
Definition: pdu.c:215
coap_get_data
int coap_get_data(const coap_pdu_t *pdu, size_t *len, uint8_t **data)
Retrieves the length and data pointer of specified PDU.
Definition: pdu.c:318
coap_pdu_parse_header
int coap_pdu_parse_header(coap_pdu_t *pdu, coap_proto_t proto)
Decode the protocol specific header for the specified PDU.
Definition: pdu.c:460
coap_pdu_init
coap_pdu_t * coap_pdu_init(uint8_t type, uint8_t code, uint16_t tid, size_t size)
Creates a new CoAP PDU with at least enough storage space for the given size maximum message size...
Definition: pdu.c:79
coap_pdu_resize
int coap_pdu_resize(coap_pdu_t *pdu, size_t new_size)
Dynamically grows the size of pdu to new_size.
Definition: pdu.c:140
coap_pdu_t
structure for CoAP PDUs token, if any, follows the fixed size header, then options until payload mark...
Definition: pdu.h:287
coap_pdu_t::data
uint8_t * data
first byte of payload, if any
Definition: pdu.h:299
coap_session_t::proto
coap_proto_t proto
protocol used
Definition: coap_session.h:60
coap_pdu_t::used_size
size_t used_size
used bytes of storage for token, options and payload
Definition: pdu.h:296
coap_pdu_t::alloc_size
size_t alloc_size
allocated storage for token, options and payload
Definition: pdu.h:295
coap_pdu_t::token
uint8_t * token
first byte of token, if any, or options
Definition: pdu.h:298
COAP_DEPRECATED
#define COAP_DEPRECATED
Definition: libcoap.h:46
coap_pdu_t::max_size
size_t max_size
maximum size for token, options and payload, or zero for variable size pdu
Definition: pdu.h:297
coap_session_t::type
coap_session_type_t type
client or server side socket
Definition: coap_session.h:61
coap_pdu_t
struct coap_pdu_t coap_pdu_t
structure for CoAP PDUs token, if any, follows the fixed size header, then options until payload mark...
coap_option::key
uint16_t key
Definition: pdu.h:267
coap_pdu_t::max_delta
uint16_t max_delta
highest option number
Definition: pdu.h:294
coap_delete_pdu
void coap_delete_pdu(coap_pdu_t *)
Dispose of an CoAP PDU and frees associated storage.
Definition: pdu.c:127
coap_pdu_t::max_hdr_size
uint8_t max_hdr_size
space reserved for protocol-specific header
Definition: pdu.h:290
coap_pdu_encode_header
size_t coap_pdu_encode_header(coap_pdu_t *pdu, coap_proto_t proto)
Compose the protocol specific header for the specified PDU.
Definition: pdu.c:568
coap_add_data_after
uint8_t * coap_add_data_after(coap_pdu_t *pdu, size_t len)
Adds given data to the pdu that is passed as first parameter but does not copyt it.
Definition: pdu.c:300
coap_pdu_t::hdr_size
uint8_t hdr_size
actaul size used for protocol-specific header
Definition: pdu.h:291
uint8_t
unsigned char uint8_t
Definition: uthash.h:79
coap_pdu_t::token_length
uint8_t token_length
length of Token
Definition: pdu.h:292
coap_pdu_parse_opt
int coap_pdu_parse_opt(coap_pdu_t *pdu)
Verify consistency in the given CoAP PDU structure and locate the data.
Definition: pdu.c:492
coap_pdu_parse_header_size
size_t coap_pdu_parse_header_size(coap_proto_t proto, const uint8_t *data)
Interprets data to determine the number of bytes in the header.
Definition: pdu.c:405
coap_pdu_t::tid
uint16_t tid
transaction id, if any, in regular host byte order
Definition: pdu.h:293