This module includes functions that control DNS communication. More...

Classes
struct	otDnsQuery
	This structure implements DNS Query parameters. More...

Macros
#define	OT_DNS_MAX_HOSTNAME_LENGTH 62
	Maximum allowed hostname length (maximum label size - 1 for compression).

#define	OT_DNS_DEFAULT_DNS_SERVER_IP "2001:4860:4860::8888"
	Defines default DNS Server address - Google DNS.

#define	OT_DNS_DEFAULT_DNS_SERVER_PORT 53
	Defines default DNS Server port.

Typedefs
typedef struct otDnsQuery	otDnsQuery
	This structure implements DNS Query parameters.

typedef void(*	otDnsResponseHandler) (void aContext, const char aHostname, otIp6Address *aAddress, uint32_t aTtl, otError aResult)
	This function pointer is called when a DNS response is received. More...

Functions
otError	otDnsClientQuery (otInstance aInstance, const otDnsQuery aQuery, otDnsResponseHandler aHandler, void *aContext)
	This function sends a DNS query for AAAA (IPv6) record. More...

Detailed Description

This module includes functions that control DNS communication.

Typedef Documentation

typedef void(* otDnsResponseHandler) (void *aContext, const char *aHostname, otIp6Address *aAddress, uint32_t aTtl, otError aResult)

This function pointer is called when a DNS response is received.

Parameters

[in]	aContext	A pointer to application-specific context.
[in]	aHostname	Identifies hostname related with DNS response.
[in]	aAddress	A pointer to the IPv6 address received in DNS response. May be null.
[in]	aTtl	Specifies the maximum time in seconds that the resource record may be cached.
[in]	aResult	A result of the DNS transaction.

Return values

OT_ERROR_NONE	A response was received successfully and IPv6 address is provided in `aAddress`.
OT_ERROR_ABORT	A DNS transaction was aborted by stack.
OT_ERROR_RESPONSE_TIMEOUT	No DNS response has been received within timeout.
OT_ERROR_NOT_FOUND	A response was received but no IPv6 address has been found.
OT_ERROR_FAILED	A response was received but status code is different than success.

This function sends a DNS query for AAAA (IPv6) record.

This function is available only if feature OPENTHREAD_ENABLE_DNS_CLIENT is enabled.

Parameters

[in]	aInstance	A pointer to an OpenThread instance.
[in]	aQuery	A pointer to specify DNS query parameters.
[in]	aHandler	A function pointer that shall be called on response reception or time-out.
[in]	aContext	A pointer to arbitrary context information.