coap.h File Reference

CoAP implementation for Zephyr. More...

#include <zephyr/types.h>
#include <stddef.h>
#include <stdbool.h>
#include <zephyr/net/net_ip.h>
#include <zephyr/sys/math_extras.h>
#include <zephyr/sys/slist.h>

Go to the source code of this file.

Data Structures
struct	coap_resource
	Description of CoAP resource. More...
struct	coap_observer
	Represents a remote device that is observing a local resource. More...
struct	coap_packet
	Representation of a CoAP Packet. More...
struct	coap_option
	Representation of a CoAP option. More...
struct	coap_transmission_parameters
	CoAP transmission parameters. More...
struct	coap_pending
	Represents a request awaiting for an acknowledgment (ACK). More...
struct	coap_reply
	Represents the handler for the reply of a request, it is also used when observing resources. More...
struct	coap_block_context
	Represents the current state of a block-wise transaction. More...

Macros
#define	COAP_MAKE_RESPONSE_CODE(class, det)   ((class << 5) | (det))
	Utility macro to create a CoAP response code.

Typedefs
typedef int(*	coap_method_t) (struct coap_resource *resource, struct coap_packet *request, struct sockaddr *addr, socklen_t addr_len)
	Type of the callback being called when a resource's method is invoked by the remote entity.
typedef void(*	coap_notify_t) (struct coap_resource *resource, struct coap_observer *observer)
	Type of the callback being called when a resource's has observers to be informed when an update happens.
typedef int(*	coap_reply_t) (const struct coap_packet *response, struct coap_reply *reply, const struct sockaddr *from)
	Helper function to be called when a response matches the a pending request.

Enumerations
enum	coap_option_num {   COAP_OPTION_IF_MATCH = 1 , COAP_OPTION_URI_HOST = 3 , COAP_OPTION_ETAG = 4 , COAP_OPTION_IF_NONE_MATCH = 5 ,   COAP_OPTION_OBSERVE = 6 , COAP_OPTION_URI_PORT = 7 , COAP_OPTION_LOCATION_PATH = 8 , COAP_OPTION_URI_PATH = 11 ,   COAP_OPTION_CONTENT_FORMAT = 12 , COAP_OPTION_MAX_AGE = 14 , COAP_OPTION_URI_QUERY = 15 , COAP_OPTION_ACCEPT = 17 ,   COAP_OPTION_LOCATION_QUERY = 20 , COAP_OPTION_BLOCK2 = 23 , COAP_OPTION_BLOCK1 = 27 , COAP_OPTION_SIZE2 = 28 ,   COAP_OPTION_PROXY_URI = 35 , COAP_OPTION_PROXY_SCHEME = 39 , COAP_OPTION_SIZE1 = 60 , COAP_OPTION_ECHO = 252 ,   COAP_OPTION_NO_RESPONSE = 258 , COAP_OPTION_REQUEST_TAG = 292 }
	Set of CoAP packet options we are aware of. More...
enum	coap_method {   COAP_METHOD_GET = 1 , COAP_METHOD_POST = 2 , COAP_METHOD_PUT = 3 , COAP_METHOD_DELETE = 4 ,   COAP_METHOD_FETCH = 5 , COAP_METHOD_PATCH = 6 , COAP_METHOD_IPATCH = 7 }
	Available request methods. More...
enum	coap_msgtype { COAP_TYPE_CON = 0 , COAP_TYPE_NON_CON = 1 , COAP_TYPE_ACK = 2 , COAP_TYPE_RESET = 3 }
	CoAP packets may be of one of these types. More...
enum	coap_response_code {   COAP_RESPONSE_CODE_OK = (( 2 << 5) | ( 0 )) , COAP_RESPONSE_CODE_CREATED = (( 2 << 5) | ( 1 )) , COAP_RESPONSE_CODE_DELETED = (( 2 << 5) | ( 2 )) , COAP_RESPONSE_CODE_VALID = (( 2 << 5) | ( 3 )) ,   COAP_RESPONSE_CODE_CHANGED = (( 2 << 5) | ( 4 )) , COAP_RESPONSE_CODE_CONTENT = (( 2 << 5) | ( 5 )) , COAP_RESPONSE_CODE_CONTINUE = (( 2 << 5) | ( 31 )) , COAP_RESPONSE_CODE_BAD_REQUEST = (( 4 << 5) | ( 0 )) ,   COAP_RESPONSE_CODE_UNAUTHORIZED = (( 4 << 5) | ( 1 )) , COAP_RESPONSE_CODE_BAD_OPTION = (( 4 << 5) | ( 2 )) , COAP_RESPONSE_CODE_FORBIDDEN = (( 4 << 5) | ( 3 )) , COAP_RESPONSE_CODE_NOT_FOUND = (( 4 << 5) | ( 4 )) ,   COAP_RESPONSE_CODE_NOT_ALLOWED = (( 4 << 5) | ( 5 )) , COAP_RESPONSE_CODE_NOT_ACCEPTABLE = (( 4 << 5) | ( 6 )) , COAP_RESPONSE_CODE_INCOMPLETE = (( 4 << 5) | ( 8 )) , COAP_RESPONSE_CODE_CONFLICT = (( 4 << 5) | ( 9 )) ,   COAP_RESPONSE_CODE_PRECONDITION_FAILED = (( 4 << 5) | ( 12 )) , COAP_RESPONSE_CODE_REQUEST_TOO_LARGE = (( 4 << 5) | ( 13 )) , COAP_RESPONSE_CODE_UNSUPPORTED_CONTENT_FORMAT , COAP_RESPONSE_CODE_UNPROCESSABLE_ENTITY = (( 4 << 5) | ( 22 )) ,   COAP_RESPONSE_CODE_TOO_MANY_REQUESTS = (( 4 << 5) | ( 29 )) , COAP_RESPONSE_CODE_INTERNAL_ERROR = (( 5 << 5) | ( 0 )) , COAP_RESPONSE_CODE_NOT_IMPLEMENTED = (( 5 << 5) | ( 1 )) , COAP_RESPONSE_CODE_BAD_GATEWAY = (( 5 << 5) | ( 2 )) ,   COAP_RESPONSE_CODE_SERVICE_UNAVAILABLE = (( 5 << 5) | ( 3 )) , COAP_RESPONSE_CODE_GATEWAY_TIMEOUT = (( 5 << 5) | ( 4 )) , COAP_RESPONSE_CODE_PROXYING_NOT_SUPPORTED }
	Set of response codes available for a response packet. More...
enum	coap_content_format {   COAP_CONTENT_FORMAT_TEXT_PLAIN = 0 , COAP_CONTENT_FORMAT_APP_LINK_FORMAT = 40 , COAP_CONTENT_FORMAT_APP_XML = 41 , COAP_CONTENT_FORMAT_APP_OCTET_STREAM = 42 ,   COAP_CONTENT_FORMAT_APP_EXI = 47 , COAP_CONTENT_FORMAT_APP_JSON = 50 , COAP_CONTENT_FORMAT_APP_JSON_PATCH_JSON = 51 , COAP_CONTENT_FORMAT_APP_MERGE_PATCH_JSON = 52 ,   COAP_CONTENT_FORMAT_APP_CBOR = 60 }
	Set of Content-Format option values for CoAP. More...
enum	coap_no_response { COAP_NO_RESPONSE_SUPPRESS_2_XX = 0x02 , COAP_NO_RESPONSE_SUPPRESS_4_XX = 0x08 , COAP_NO_RESPONSE_SUPPRESS_5_XX = 0x10 , COAP_NO_RESPONSE_SUPPRESS_ALL }
	Set of No-Response option values for CoAP. More...
enum	coap_block_size {   COAP_BLOCK_16 , COAP_BLOCK_32 , COAP_BLOCK_64 , COAP_BLOCK_128 ,   COAP_BLOCK_256 , COAP_BLOCK_512 , COAP_BLOCK_1024 }
	Represents the size of each block that will be transferred using block-wise transfers [RFC7959]: More...

Functions
uint8_t	coap_header_get_version (const struct coap_packet *cpkt)
	Returns the version present in a CoAP packet.
uint8_t	coap_header_get_type (const struct coap_packet *cpkt)
	Returns the type of the CoAP packet.
uint8_t	coap_header_get_token (const struct coap_packet *cpkt, uint8_t *token)
	Returns the token (if any) in the CoAP packet.
uint8_t	coap_header_get_code (const struct coap_packet *cpkt)
	Returns the code of the CoAP packet.
int	coap_header_set_code (const struct coap_packet *cpkt, uint8_t code)
	Modifies the code of the CoAP packet.
uint16_t	coap_header_get_id (const struct coap_packet *cpkt)
	Returns the message id associated with the CoAP packet.
const uint8_t *	coap_packet_get_payload (const struct coap_packet *cpkt, uint16_t *len)
	Returns the data pointer and length of the CoAP packet.
bool	coap_uri_path_match (const char *const *path, struct coap_option *options, uint8_t opt_num)
	Verify if CoAP URI path matches with provided options.
int	coap_packet_parse (struct coap_packet *cpkt, uint8_t *data, uint16_t len, struct coap_option *options, uint8_t opt_num)
	Parses the CoAP packet in data, validating it and initializing cpkt.
int	coap_packet_set_path (struct coap_packet *cpkt, const char *path)
	Parses provided coap path (with/without query) or query and appends that as options to the cpkt.
int	coap_packet_init (struct coap_packet *cpkt, uint8_t *data, uint16_t max_len, uint8_t ver, uint8_t type, uint8_t token_len, const uint8_t *token, uint8_t code, uint16_t id)
	Creates a new CoAP Packet from input data.
int	coap_ack_init (struct coap_packet *cpkt, const struct coap_packet *req, uint8_t *data, uint16_t max_len, uint8_t code)
	Create a new CoAP Acknowledgment message for given request.
int	coap_rst_init (struct coap_packet *cpkt, const struct coap_packet *req, uint8_t *data, uint16_t max_len)
	Create a new CoAP Reset message for given request.
uint8_t *	coap_next_token (void)
	Returns a randomly generated array of 8 bytes, that can be used as a message's token.
uint16_t	coap_next_id (void)
	Helper to generate message ids.
int	coap_find_options (const struct coap_packet *cpkt, uint16_t code, struct coap_option *options, uint16_t veclen)
	Return the values associated with the option of value code.
int	coap_packet_append_option (struct coap_packet *cpkt, uint16_t code, const uint8_t *value, uint16_t len)
	Appends an option to the packet.
int	coap_packet_remove_option (struct coap_packet *cpkt, uint16_t code)
	Remove an option from the packet.
unsigned int	coap_option_value_to_int (const struct coap_option *option)
	Converts an option to its integer representation.
int	coap_append_option_int (struct coap_packet *cpkt, uint16_t code, unsigned int val)
	Appends an integer value option to the packet.
int	coap_packet_append_payload_marker (struct coap_packet *cpkt)
	Append payload marker to CoAP packet.
int	coap_packet_append_payload (struct coap_packet *cpkt, const uint8_t *payload, uint16_t payload_len)
	Append payload to CoAP packet.
bool	coap_packet_is_request (const struct coap_packet *cpkt)
	Check if a CoAP packet is a CoAP request.
int	coap_handle_request_len (struct coap_packet *cpkt, struct coap_resource *resources, size_t resources_len, struct coap_option *options, uint8_t opt_num, struct sockaddr *addr, socklen_t addr_len)
	When a request is received, call the appropriate methods of the matching resources.
int	coap_handle_request (struct coap_packet *cpkt, struct coap_resource *resources, struct coap_option *options, uint8_t opt_num, struct sockaddr *addr, socklen_t addr_len)
	When a request is received, call the appropriate methods of the matching resources.
static uint16_t	coap_block_size_to_bytes (enum coap_block_size block_size)
	Helper for converting the enumeration to the size expressed in bytes.
static enum coap_block_size	coap_bytes_to_block_size (uint16_t bytes)
	Helper for converting block size in bytes to enumeration.
int	coap_block_transfer_init (struct coap_block_context *ctx, enum coap_block_size block_size, size_t total_size)
	Initializes the context of a block-wise transfer.
int	coap_append_descriptive_block_option (struct coap_packet *cpkt, struct coap_block_context *ctx)
	Append BLOCK1 or BLOCK2 option to the packet.
bool	coap_has_descriptive_block_option (struct coap_packet *cpkt)
	Check if a descriptive block option is set in the packet.
int	coap_remove_descriptive_block_option (struct coap_packet *cpkt)
	Remove BLOCK1 or BLOCK2 option from the packet.
bool	coap_block_has_more (struct coap_packet *cpkt)
	Check if BLOCK1 or BLOCK2 option has more flag set.
int	coap_append_block1_option (struct coap_packet *cpkt, struct coap_block_context *ctx)
	Append BLOCK1 option to the packet.
int	coap_append_block2_option (struct coap_packet *cpkt, struct coap_block_context *ctx)
	Append BLOCK2 option to the packet.
int	coap_append_size1_option (struct coap_packet *cpkt, struct coap_block_context *ctx)
	Append SIZE1 option to the packet.
int	coap_append_size2_option (struct coap_packet *cpkt, struct coap_block_context *ctx)
	Append SIZE2 option to the packet.
int	coap_get_option_int (const struct coap_packet *cpkt, uint16_t code)
	Get the integer representation of a CoAP option.
int	coap_get_block1_option (const struct coap_packet *cpkt, bool *has_more, uint32_t *block_number)
	Get the block size, more flag and block number from the CoAP block1 option.
int	coap_get_block2_option (const struct coap_packet *cpkt, bool *has_more, uint32_t *block_number)
	Get values from CoAP block2 option.
int	coap_update_from_block (const struct coap_packet *cpkt, struct coap_block_context *ctx)
	Retrieves BLOCK{1,2} and SIZE{1,2} from cpkt and updates ctx accordingly.
int	coap_next_block_for_option (const struct coap_packet *cpkt, struct coap_block_context *ctx, enum coap_option_num option)
	Updates ctx according to option set in cpkt so after this is called the current entry indicates the correct offset in the body of data being transferred.
size_t	coap_next_block (const struct coap_packet *cpkt, struct coap_block_context *ctx)
	Updates ctx so after this is called the current entry indicates the correct offset in the body of data being transferred.
void	coap_observer_init (struct coap_observer *observer, const struct coap_packet *request, const struct sockaddr *addr)
	Indicates that the remote device referenced by addr, with request, wants to observe a resource.
bool	coap_register_observer (struct coap_resource *resource, struct coap_observer *observer)
	After the observer is initialized, associate the observer with an resource.
bool	coap_remove_observer (struct coap_resource *resource, struct coap_observer *observer)
	Remove this observer from the list of registered observers of that resource.
struct coap_observer *	coap_find_observer (struct coap_observer *observers, size_t len, const struct sockaddr *addr, const uint8_t *token, uint8_t token_len)
	Returns the observer that matches address addr and has token token.
struct coap_observer *	coap_find_observer_by_addr (struct coap_observer *observers, size_t len, const struct sockaddr *addr)
	Returns the observer that matches address addr.
struct coap_observer *	coap_find_observer_by_token (struct coap_observer *observers, size_t len, const uint8_t *token, uint8_t token_len)
	Returns the observer that has token token.
struct coap_observer *	coap_observer_next_unused (struct coap_observer *observers, size_t len)
	Returns the next available observer representation.
void	coap_reply_init (struct coap_reply *reply, const struct coap_packet *request)
	Indicates that a reply is expected for request.
int	coap_pending_init (struct coap_pending *pending, const struct coap_packet *request, const struct sockaddr *addr, const struct coap_transmission_parameters *params)
	Initialize a pending request with a request.
struct coap_pending *	coap_pending_next_unused (struct coap_pending *pendings, size_t len)
	Returns the next available pending struct, that can be used to track the retransmission status of a request.
struct coap_reply *	coap_reply_next_unused (struct coap_reply *replies, size_t len)
	Returns the next available reply struct, so it can be used to track replies and notifications received.
struct coap_pending *	coap_pending_received (const struct coap_packet *response, struct coap_pending *pendings, size_t len)
	After a response is received, returns if there is any matching pending request exits.
struct coap_reply *	coap_response_received (const struct coap_packet *response, const struct sockaddr *from, struct coap_reply *replies, size_t len)
	After a response is received, call coap_reply_t handler registered in coap_reply structure.
struct coap_pending *	coap_pending_next_to_expire (struct coap_pending *pendings, size_t len)
	Returns the next pending about to expire, pending->timeout informs how many ms to next expiration.
bool	coap_pending_cycle (struct coap_pending *pending)
	After a request is sent, user may want to cycle the pending retransmission so the timeout is updated.
void	coap_pending_clear (struct coap_pending *pending)
	Cancels the pending retransmission, so it again becomes available.
void	coap_pendings_clear (struct coap_pending *pendings, size_t len)
	Cancels all pending retransmissions, so they become available again.
size_t	coap_pendings_count (struct coap_pending *pendings, size_t len)
	Count number of pending requests.
void	coap_reply_clear (struct coap_reply *reply)
	Cancels awaiting for this reply, so it becomes available again.
void	coap_replies_clear (struct coap_reply *replies, size_t len)
	Cancels all replies, so they become available again.
int	coap_resource_notify (struct coap_resource *resource)
	Indicates that this resource was updated and that the notify callback should be called for every registered observer.
bool	coap_request_is_observe (const struct coap_packet *request)
	Returns if this request is enabling observing a resource.
struct coap_transmission_parameters	coap_get_transmission_parameters (void)
	Get currently active CoAP transmission parameters.
void	coap_set_transmission_parameters (const struct coap_transmission_parameters *params)
	Set CoAP transmission parameters.

Detailed Description

CoAP implementation for Zephyr.