IPv6

This module includes functions that control IPv6 communication.

Summary

Enumerations
Anonymous Enum 10{   OT_IP6_PROTO_HOP_OPTS = 0,   OT_IP6_PROTO_TCP = 6,   OT_IP6_PROTO_UDP = 17,   OT_IP6_PROTO_IP6 = 41,   OT_IP6_PROTO_ROUTING = 43,   OT_IP6_PROTO_FRAGMENT = 44,   OT_IP6_PROTO_ICMP6 = 58,   OT_IP6_PROTO_NONE = 59,   OT_IP6_PROTO_DST_OPTS = 60 }	enum Internet Protocol Numbers.
Anonymous Enum 8{   OT_ADDRESS_ORIGIN_THREAD = 0,   OT_ADDRESS_ORIGIN_SLAAC = 1,   OT_ADDRESS_ORIGIN_DHCPV6 = 2,   OT_ADDRESS_ORIGIN_MANUAL = 3 }	enum IPv6 Address origins.
Anonymous Enum 9{   OT_ECN_NOT_CAPABLE = 0x0,   OT_ECN_CAPABLE_0 = 0x2,   OT_ECN_CAPABLE_1 = 0x1,   OT_ECN_MARKED = 0x3 }	enum ECN statuses, represented as in the IP header.

Typedefs
otIp6Address	typedef struct otIp6Address This structure represents an IPv6 address.
otIp6AddressCallback)(const otIp6AddressInfo *aAddressInfo, bool aIsAdded, void *aContext)	typedef void(* This function pointer is called when an internal IPv6 address is added or removed.
otIp6AddressComponents	typedef struct otIp6AddressComponents This structure represents the components of an IPv6 address.
otIp6AddressInfo	typedef struct otIp6AddressInfo
otIp6InterfaceIdentifier	typedef struct otIp6InterfaceIdentifier This structure represents the Interface Identifier of an IPv6 address.
otIp6NetworkPrefix	typedef struct otIp6NetworkPrefix This structure represents the Network Prefix of an IPv6 address (most significant 64 bits of the address).
otIp6Prefix	typedef struct otIp6Prefix This structure represents an IPv6 prefix.
otIp6ReceiveCallback)(otMessage *aMessage, void *aContext)	typedef void(* This function pointer is called when an IPv6 datagram is received.
otIp6RegisterMulticastListenersCallback)(void *aContext, otError aError, uint8_t aMlrStatus, const otIp6Address *aFailedAddresses, uint8_t aFailedAddressNum)	typedef void(* This function pointer is called with results of otIp6RegisterMulticastListeners.
otIp6SlaacPrefixFilter)(otInstance *aInstance, const otIp6Prefix *aPrefix)	typedef bool(* This function pointer allows user to filter prefixes and not allow an SLAAC address based on a prefix to be added.
otMessageInfo	typedef struct otMessageInfo This structure represents the local and peer IPv6 socket addresses.
otNetifAddress	typedef struct otNetifAddress This structure represents an IPv6 network interface unicast address.
otNetifMulticastAddress	typedef struct otNetifMulticastAddress This structure represents an IPv6 network interface multicast address.
otSockAddr	typedef struct otSockAddr This structure represents an IPv6 socket address.

Variables
OT_TOOL_PACKED_END	OT_TOOL_PACKED_BEGIN struct otIp6InterfaceIdentifier

Functions
otIp6AddUnicastAddress(otInstance *aInstance, const otNetifAddress *aAddress)	otError Adds a Network Interface Address to the Thread interface.
otIp6AddUnsecurePort(otInstance *aInstance, uint16_t aPort)	otError This function adds a port to the allowed unsecured port list.
otIp6AddressFromString(const char *aString, otIp6Address *aAddress)	otError This function converts a human-readable IPv6 address string into a binary representation.
otIp6AddressToString(const otIp6Address *aAddress, char *aBuffer, uint16_t aSize)	void This function converts a given IPv6 address to a human-readable string.
otIp6ArePrefixesEqual(const otIp6Prefix *aFirst, const otIp6Prefix *aSecond)	bool Test if two IPv6 prefixes are the same.
otIp6GetMulticastAddresses(otInstance *aInstance)	const otNetifMulticastAddress * Gets the list of IPv6 multicast addresses subscribed to the Thread interface.
otIp6GetPrefix(const otIp6Address *aAddress, uint8_t aLength, otIp6Prefix *aPrefix)	void This method gets a prefix with aLength from aAddress.
otIp6GetUnicastAddresses(otInstance *aInstance)	const otNetifAddress * Gets the list of IPv6 addresses assigned to the Thread interface.
otIp6GetUnsecurePorts(otInstance *aInstance, uint8_t *aNumEntries)	const uint16_t * This function returns a pointer to the unsecure port list.
otIp6IsAddressEqual(const otIp6Address *aFirst, const otIp6Address *aSecond)	bool Test if two IPv6 addresses are the same.
otIp6IsAddressUnspecified(const otIp6Address *aAddress)	bool This function indicates whether or not a given IPv6 address is the Unspecified Address.
otIp6IsEnabled(otInstance *aInstance)	bool Indicates whether or not the IPv6 interface is up.
otIp6IsMulticastPromiscuousEnabled(otInstance *aInstance)	bool Checks if multicast promiscuous mode is enabled on the Thread interface.
otIp6IsReceiveFilterEnabled(otInstance *aInstance)	bool This function indicates whether or not Thread control traffic is filtered out when delivering IPv6 datagrams via the callback specified in otIp6SetReceiveCallback().
otIp6IsSlaacEnabled(otInstance *aInstance)	bool This function indicates whether the SLAAC module is enabled or not.
otIp6NewMessage(otInstance *aInstance, const otMessageSettings *aSettings)	otMessage * Allocate a new message buffer for sending an IPv6 message.
otIp6NewMessageFromBuffer(otInstance *aInstance, const uint8_t *aData, uint16_t aDataLength, const otMessageSettings *aSettings)	otMessage * Allocate a new message buffer and write the IPv6 datagram to the message buffer for sending an IPv6 message.
otIp6PrefixMatch(const otIp6Address *aFirst, const otIp6Address *aSecond)	uint8_t This function returns the prefix match length (bits) for two IPv6 addresses.
otIp6PrefixToString(const otIp6Prefix *aPrefix, char *aBuffer, uint16_t aSize)	void This function converts a given IPv6 prefix to a human-readable string.
otIp6ProtoToString(uint8_t aIpProto)	const char * This function converts a given IP protocol number to a human-readable string.
otIp6RegisterMulticastListeners(otInstance *aInstance, const otIp6Address *aAddresses, uint8_t aAddressNum, const uint32_t *aTimeout, otIp6RegisterMulticastListenersCallback aCallback, void *aContext)	otError This function registers Multicast Listeners to Primary Backbone Router.
otIp6RemoveAllUnsecurePorts(otInstance *aInstance)	void This function removes all ports from the allowed unsecure port list.
otIp6RemoveUnicastAddress(otInstance *aInstance, const otIp6Address *aAddress)	otError Removes a Network Interface Address from the Thread interface.
otIp6RemoveUnsecurePort(otInstance *aInstance, uint16_t aPort)	otError This function removes a port from the allowed unsecure port list.
otIp6SelectSourceAddress(otInstance *aInstance, otMessageInfo *aMessageInfo)	otError This function perform OpenThread source address selection.
otIp6Send(otInstance *aInstance, otMessage *aMessage)	otError This function sends an IPv6 datagram via the Thread interface.
otIp6SetAddressCallback(otInstance *aInstance, otIp6AddressCallback aCallback, void *aCallbackContext)	void This function registers a callback to notify internal IPv6 address changes.
otIp6SetEnabled(otInstance *aInstance, bool aEnabled)	otError Brings the IPv6 interface up or down.
otIp6SetMeshLocalIid(otInstance *aInstance, const otIp6InterfaceIdentifier *aIid)	otError This function sets the Mesh Local IID (for test purpose).
otIp6SetMulticastPromiscuousEnabled(otInstance *aInstance, bool aEnabled)	void Enables or disables multicast promiscuous mode on the Thread interface.
otIp6SetReceiveCallback(otInstance *aInstance, otIp6ReceiveCallback aCallback, void *aCallbackContext)	void This function registers a callback to provide received IPv6 datagrams.
otIp6SetReceiveFilterEnabled(otInstance *aInstance, bool aEnabled)	void This function sets whether or not Thread control traffic is filtered out when delivering IPv6 datagrams via the callback specified in otIp6SetReceiveCallback().
otIp6SetSlaacEnabled(otInstance *aInstance, bool aEnabled)	void This function enables/disables the SLAAC module.
otIp6SetSlaacPrefixFilter(otInstance *aInstance, otIp6SlaacPrefixFilter aFilter)	void This function sets the SLAAC module filter handler.
otIp6SockAddrToString(const otSockAddr *aSockAddr, char *aBuffer, uint16_t aSize)	void This function converts a given IPv6 socket address to a human-readable string.
otIp6SubscribeMulticastAddress(otInstance *aInstance, const otIp6Address *aAddress)	otError Subscribes the Thread interface to a Network Interface Multicast Address.
otIp6UnsubscribeMulticastAddress(otInstance *aInstance, const otIp6Address *aAddress)	otError Unsubscribes the Thread interface to a Network Interface Multicast Address.

Macros
OT_IP6_ADDRESS_SIZE 16	Size of an IPv6 address (bytes)
OT_IP6_ADDRESS_STRING_SIZE 40	Recommended size for string representation of an IPv6 address.
OT_IP6_IID_SIZE 8	Size of an IPv6 Interface Identifier (bytes)
OT_IP6_MAX_MLR_ADDRESSES 15	Max number of IPv6 addresses supported by Multicast Listener Registration.
OT_IP6_PREFIX_BITSIZE (OT_IP6_PREFIX_SIZE * 8)	Size of an IPv6 prefix (bits)
OT_IP6_PREFIX_SIZE 8	Size of an IPv6 prefix (bytes)
OT_IP6_PREFIX_STRING_SIZE 45	Recommended size for string representation of an IPv6 prefix.
OT_IP6_SOCK_ADDR_STRING_SIZE 48	Recommended size for string representation of an IPv6 socket address.

Structs
otIp6Address	This structure represents an IPv6 address.
otIp6AddressComponents	This structure represents the components of an IPv6 address.
otIp6AddressInfo	This structure represents IPv6 address information.
otIp6InterfaceIdentifier	This structure represents the Interface Identifier of an IPv6 address.
otIp6NetworkPrefix	This structure represents the Network Prefix of an IPv6 address (most significant 64 bits of the address).
otIp6Prefix	This structure represents an IPv6 prefix.
otMessageInfo	This structure represents the local and peer IPv6 socket addresses.
otNetifAddress	This structure represents an IPv6 network interface unicast address.
otNetifMulticastAddress	This structure represents an IPv6 network interface multicast address.
otSockAddr	This structure represents an IPv6 socket address.

Unions
otIp6InterfaceIdentifier::OT_TOOL_PACKED_FIELD

Enumerations

Anonymous Enum 10

 Anonymous Enum 10

Internet Protocol Numbers.

Properties
OT_IP6_PROTO_DST_OPTS	Destination Options for IPv6.
OT_IP6_PROTO_FRAGMENT	Fragment Header for IPv6.
OT_IP6_PROTO_HOP_OPTS	IPv6 Hop-by-Hop Option.
OT_IP6_PROTO_ICMP6	ICMP for IPv6.
OT_IP6_PROTO_IP6	IPv6 encapsulation.
OT_IP6_PROTO_NONE	No Next Header for IPv6.
OT_IP6_PROTO_ROUTING	Routing Header for IPv6.
OT_IP6_PROTO_TCP	Transmission Control Protocol.
OT_IP6_PROTO_UDP	User Datagram.

Anonymous Enum 8

 Anonymous Enum 8

IPv6 Address origins.

Properties
OT_ADDRESS_ORIGIN_DHCPV6	DHCPv6 assigned address.
OT_ADDRESS_ORIGIN_MANUAL	Manually assigned address.
OT_ADDRESS_ORIGIN_SLAAC	SLAAC assigned address.
OT_ADDRESS_ORIGIN_THREAD	Thread assigned address (ALOC, RLOC, MLEID, etc)

Anonymous Enum 9

 Anonymous Enum 9

ECN statuses, represented as in the IP header.

Properties
OT_ECN_CAPABLE_0	ECT(0)
OT_ECN_CAPABLE_1	ECT(1)
OT_ECN_MARKED	Congestion encountered (CE)
OT_ECN_NOT_CAPABLE	Non-ECT.

Typedefs

otIp6Address

struct otIp6Address otIp6Address

This structure represents an IPv6 address.

otIp6AddressCallback

void(* otIp6AddressCallback)(const otIp6AddressInfo *aAddressInfo, bool aIsAdded, void *aContext)

This function pointer is called when an internal IPv6 address is added or removed.

Details
Parameters	[in] aAddressInfo A pointer to the IPv6 address information. [in] aIsAdded TRUE if the aAddress was added, FALSE if aAddress was removed. [in] aContext A pointer to application-specific context.

otIp6AddressComponents

struct otIp6AddressComponents otIp6AddressComponents

This structure represents the components of an IPv6 address.

otIp6AddressInfo

struct otIp6AddressInfo otIp6AddressInfo

otIp6InterfaceIdentifier

struct otIp6InterfaceIdentifier otIp6InterfaceIdentifier

This structure represents the Interface Identifier of an IPv6 address.

otIp6NetworkPrefix

struct otIp6NetworkPrefix otIp6NetworkPrefix

This structure represents the Network Prefix of an IPv6 address (most significant 64 bits of the address).

otIp6Prefix

struct otIp6Prefix otIp6Prefix

This structure represents an IPv6 prefix.

otIp6ReceiveCallback

void(* otIp6ReceiveCallback)(otMessage *aMessage, void *aContext)

This function pointer is called when an IPv6 datagram is received.

Details
Parameters	[in] aMessage A pointer to the message buffer containing the received IPv6 datagram. This function transfers the ownership of the aMessage to the receiver of the callback. The message should be freed by the receiver of the callback after it is processed (see otMessageFree()). [in] aContext A pointer to application-specific context.

otIp6RegisterMulticastListenersCallback

void(* otIp6RegisterMulticastListenersCallback)(void *aContext, otError aError, uint8_t aMlrStatus, const otIp6Address *aFailedAddresses, uint8_t aFailedAddressNum)

This function pointer is called with results of otIp6RegisterMulticastListeners.

Details

Parameters

[in] aContext A pointer to the user context. [in] aError OT_ERROR_NONE when successfully sent MLR.req and received MLR.rsp, OT_ERROR_RESPONSE_TIMEOUT when failed to receive MLR.rsp, OT_ERROR_PARSE when failed to parse MLR.rsp. [in] aMlrStatus The Multicast Listener Registration status when aError is OT_ERROR_NONE. [in] aFailedAddresses A pointer to the failed IPv6 addresses when aError is OT_ERROR_NONE. [in] aFailedAddressNum The number of failed IPv6 addresses when aError is OT_ERROR_NONE.

See also:
otIp6RegisterMulticastListeners

otIp6SlaacPrefixFilter

bool(* otIp6SlaacPrefixFilter)(otInstance *aInstance, const otIp6Prefix *aPrefix)

This function pointer allows user to filter prefixes and not allow an SLAAC address based on a prefix to be added.

otIp6SetSlaacPrefixFilter() can be used to set the filter handler. The filter handler is invoked by SLAAC module when it is about to add a SLAAC address based on a prefix. Its boolean return value determines whether the address is filtered (not added) or not.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aPrefix A pointer to prefix for which SLAAC address is about to be added.
Return Values	TRUE Indicates that the SLAAC address based on the prefix should be filtered and NOT added. FALSE Indicates that the SLAAC address based on the prefix should be added.

otMessageInfo

struct otMessageInfo otMessageInfo

This structure represents the local and peer IPv6 socket addresses.

otNetifAddress

struct otNetifAddress otNetifAddress

This structure represents an IPv6 network interface unicast address.

otNetifMulticastAddress

struct otNetifMulticastAddress otNetifMulticastAddress

This structure represents an IPv6 network interface multicast address.

otSockAddr

struct otSockAddr otSockAddr

This structure represents an IPv6 socket address.

Variables

OT_TOOL_PACKED_END

OT_TOOL_PACKED_BEGIN struct otIp6InterfaceIdentifier OT_TOOL_PACKED_END

Functions

otIp6AddUnicastAddress

otError otIp6AddUnicastAddress(
  otInstance *aInstance,
  const otNetifAddress *aAddress
)

Adds a Network Interface Address to the Thread interface.

The passed-in instance aAddress is copied by the Thread interface. The Thread interface only supports a fixed number of externally added unicast addresses. See OPENTHREAD_CONFIG_IP6_MAX_EXT_UCAST_ADDRS.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aAddress A pointer to a Network Interface Address.
Return Values	OT_ERROR_NONE Successfully added (or updated) the Network Interface Address. OT_ERROR_INVALID_ARGS The IP Address indicated by aAddress is an internal address. OT_ERROR_NO_BUFS The Network Interface is already storing the maximum allowed external addresses.

otIp6AddUnsecurePort

otError otIp6AddUnsecurePort(
  otInstance *aInstance,
  uint16_t aPort
)

This function adds a port to the allowed unsecured port list.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aPort The port value.
Return Values	OT_ERROR_NONE The port was successfully added to the allowed unsecure port list. OT_ERROR_INVALID_ARGS The port is invalid (value 0 is reserved for internal use). OT_ERROR_NO_BUFS The unsecure port list is full.

otIp6AddressFromString

otError otIp6AddressFromString(
  const char *aString,
  otIp6Address *aAddress
)

This function converts a human-readable IPv6 address string into a binary representation.

Details
Parameters	[in] aString A pointer to a NULL-terminated string. [out] aAddress A pointer to an IPv6 address.
Return Values	OT_ERROR_NONE Successfully parsed the string. OT_ERROR_INVALID_ARGS Failed to parse the string.

otIp6AddressToString

void otIp6AddressToString(
  const otIp6Address *aAddress,
  char *aBuffer,
  uint16_t aSize
)

This function converts a given IPv6 address to a human-readable string.

The IPv6 address string is formatted as 16 hex values separated by ':' (i.e., "%x:%x:%x:...:%x").

If the resulting string does not fit in aBuffer (within its aSize characters), the string will be truncated but the outputted string is always null-terminated.

Details
Parameters	[in] aAddress A pointer to an IPv6 address (MUST NOT be NULL). [out] aBuffer A pointer to a char array to output the string (MUST NOT be NULL). [in] aSize The size of aBuffer (in bytes). Recommended to use OT_IP6_ADDRESS_STRING_SIZE.

otIp6ArePrefixesEqual

bool otIp6ArePrefixesEqual(
  const otIp6Prefix *aFirst,
  const otIp6Prefix *aSecond
)

Test if two IPv6 prefixes are the same.

Details
Parameters	[in] aFirst A pointer to the first IPv6 prefix to compare. [in] aSecond A pointer to the second IPv6 prefix to compare.
Return Values	TRUE The two IPv6 prefixes are the same. FALSE The two IPv6 prefixes are not the same.

otIp6GetMulticastAddresses

const otNetifMulticastAddress * otIp6GetMulticastAddresses(
  otInstance *aInstance
)

Gets the list of IPv6 multicast addresses subscribed to the Thread interface.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance.
Returns	A pointer to the first Network Interface Multicast Address.

otIp6GetPrefix

void otIp6GetPrefix(
  const otIp6Address *aAddress,
  uint8_t aLength,
  otIp6Prefix *aPrefix
)

This method gets a prefix with aLength from aAddress.

Details
Parameters	[in] aAddress A pointer to an IPv6 address. [in] aLength The length of prefix in bits. [out] aPrefix A pointer to output the IPv6 prefix.

otIp6GetUnicastAddresses

const otNetifAddress * otIp6GetUnicastAddresses(
  otInstance *aInstance
)

Gets the list of IPv6 addresses assigned to the Thread interface.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance.
Returns	A pointer to the first Network Interface Address.

otIp6GetUnsecurePorts

const uint16_t * otIp6GetUnsecurePorts(
  otInstance *aInstance,
  uint8_t *aNumEntries
)

This function returns a pointer to the unsecure port list.

Note: Port value 0 is used to indicate an invalid entry.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [out] aNumEntries The number of entries in the list.
Returns	A pointer to the unsecure port list.

otIp6IsAddressEqual

bool otIp6IsAddressEqual(
  const otIp6Address *aFirst,
  const otIp6Address *aSecond
)

Test if two IPv6 addresses are the same.

Details
Parameters	[in] aFirst A pointer to the first IPv6 address to compare. [in] aSecond A pointer to the second IPv6 address to compare.
Return Values	TRUE The two IPv6 addresses are the same. FALSE The two IPv6 addresses are not the same.

otIp6IsAddressUnspecified

bool otIp6IsAddressUnspecified(
  const otIp6Address *aAddress
)

This function indicates whether or not a given IPv6 address is the Unspecified Address.

Details
Parameters	[in] aAddress A pointer to an IPv6 address.
Return Values	TRUE If the IPv6 address is the Unspecified Address. FALSE If the IPv6 address is not the Unspecified Address.

otIp6IsEnabled

bool otIp6IsEnabled(
  otInstance *aInstance
)

Indicates whether or not the IPv6 interface is up.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance.
Return Values	TRUE The IPv6 interface is enabled. FALSE The IPv6 interface is disabled.

otIp6IsMulticastPromiscuousEnabled

bool otIp6IsMulticastPromiscuousEnabled(
  otInstance *aInstance
)

Checks if multicast promiscuous mode is enabled on the Thread interface.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance.

See also:
otIp6SetMulticastPromiscuousEnabled

otIp6IsReceiveFilterEnabled

bool otIp6IsReceiveFilterEnabled(
  otInstance *aInstance
)

This function indicates whether or not Thread control traffic is filtered out when delivering IPv6 datagrams via the callback specified in otIp6SetReceiveCallback().

Details
Parameters	[in] aInstance A pointer to an OpenThread instance.
Returns	TRUE if Thread control traffic is filtered out, FALSE otherwise.

See also:
otIp6SetReceiveCallback
otIp6SetReceiveFilterEnabled

otIp6IsSlaacEnabled

bool otIp6IsSlaacEnabled(
  otInstance *aInstance
)

This function indicates whether the SLAAC module is enabled or not.

This function requires the build-time feature OPENTHREAD_CONFIG_IP6_SLAAC_ENABLE to be enabled.

Details
Return Values	TRUE SLAAC module is enabled. FALSE SLAAC module is disabled.

otIp6NewMessage

otMessage * otIp6NewMessage(
  otInstance *aInstance,
  const otMessageSettings *aSettings
)

Allocate a new message buffer for sending an IPv6 message.

Note: If aSettings is 'NULL', the link layer security is enabled and the message priority is set to OT_MESSAGE_PRIORITY_NORMAL by default.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aSettings A pointer to the message settings or NULL to set default settings.
Returns	A pointer to the message buffer or NULL if no message buffers are available or parameters are invalid.

See also:
otMessageFree

otIp6NewMessageFromBuffer

otMessage * otIp6NewMessageFromBuffer(
  otInstance *aInstance,
  const uint8_t *aData,
  uint16_t aDataLength,
  const otMessageSettings *aSettings
)

Allocate a new message buffer and write the IPv6 datagram to the message buffer for sending an IPv6 message.

Note: If aSettings is NULL, the link layer security is enabled and the message priority is obtained from IPv6 message itself. If aSettings is not NULL, the aSetting->mPriority is ignored and obtained from IPv6 message itself.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aData A pointer to the IPv6 datagram buffer. [in] aDataLength The size of the IPv6 datagram buffer pointed by aData. [in] aSettings A pointer to the message settings or NULL to set default settings.
Returns	A pointer to the message or NULL if malformed IPv6 header or insufficient message buffers are available.

See also:
otMessageFree

otIp6PrefixMatch

uint8_t otIp6PrefixMatch(
  const otIp6Address *aFirst,
  const otIp6Address *aSecond
)

This function returns the prefix match length (bits) for two IPv6 addresses.

Details
Parameters	[in] aFirst A pointer to the first IPv6 address. [in] aSecond A pointer to the second IPv6 address.
Returns	The prefix match length in bits.

otIp6PrefixToString

void otIp6PrefixToString(
  const otIp6Prefix *aPrefix,
  char *aBuffer,
  uint16_t aSize
)

This function converts a given IPv6 prefix to a human-readable string.

The IPv6 address string is formatted as "%x:%x:%x:...[::]/plen".

If the resulting string does not fit in aBuffer (within its aSize characters), the string will be truncated but the outputted string is always null-terminated.

Details
Parameters	[in] aPrefix A pointer to an IPv6 prefix (MUST NOT be NULL). [out] aBuffer A pointer to a char array to output the string (MUST NOT be NULL). [in] aSize The size of aBuffer (in bytes). Recommended to use OT_IP6_PREFIX_STRING_SIZE.

otIp6ProtoToString

const char * otIp6ProtoToString(
  uint8_t aIpProto
)

This function converts a given IP protocol number to a human-readable string.

Details
Parameters	[in] aIpProto An IP protocol number (OT_IP6_PROTO_* enumeration).
Returns	A string representing aIpProto.

otIp6RegisterMulticastListeners

otError otIp6RegisterMulticastListeners(
  otInstance *aInstance,
  const otIp6Address *aAddresses,
  uint8_t aAddressNum,
  const uint32_t *aTimeout,
  otIp6RegisterMulticastListenersCallback aCallback,
  void *aContext
)

This function registers Multicast Listeners to Primary Backbone Router.

Note: only available when both OPENTHREAD_CONFIG_TMF_PROXY_MLR_ENABLE and OPENTHREAD_CONFIG_COMMISSIONER_ENABLE are enabled)

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aAddresses A Multicast Address Array to register. [in] aAddressNum The number of Multicast Address to register (0 if aAddresses is NULL). [in] aTimeout A pointer to the timeout value (in seconds) to be included in MLR.req. A timeout value of 0 removes the corresponding Multicast Listener. If NULL, MLR.req would have no Timeout Tlv by default. [in] aCallback A pointer to the callback function. [in] aContext A pointer to the user context.
Return Values	OT_ERROR_NONE Successfully sent MLR.req. The aCallback will be called iff this method returns OT_ERROR_NONE. OT_ERROR_BUSY If a previous registration was ongoing. OT_ERROR_INVALID_ARGS If one or more arguments are invalid. OT_ERROR_INVALID_STATE If the device was not in a valid state to send MLR.req (e.g. Commissioner not started, Primary Backbone Router not found). OT_ERROR_NO_BUFS If insufficient message buffers available.

See also:
otIp6RegisterMulticastListenersCallback

otIp6RemoveAllUnsecurePorts

void otIp6RemoveAllUnsecurePorts(
  otInstance *aInstance
)

This function removes all ports from the allowed unsecure port list.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance.

otIp6RemoveUnicastAddress

otError otIp6RemoveUnicastAddress(
  otInstance *aInstance,
  const otIp6Address *aAddress
)

Removes a Network Interface Address from the Thread interface.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aAddress A pointer to an IP Address.
Return Values	OT_ERROR_NONE Successfully removed the Network Interface Address. OT_ERROR_INVALID_ARGS The IP Address indicated by aAddress is an internal address. OT_ERROR_NOT_FOUND The IP Address indicated by aAddress was not found.

otIp6RemoveUnsecurePort

otError otIp6RemoveUnsecurePort(
  otInstance *aInstance,
  uint16_t aPort
)

This function removes a port from the allowed unsecure port list.

Note: This function removes aPort by overwriting aPort with the element after aPort in the internal port list. Be careful when calling otIp6GetUnsecurePorts() followed by otIp6RemoveUnsecurePort() to remove unsecure ports.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aPort The port value.
Return Values	OT_ERROR_NONE The port was successfully removed from the allowed unsecure port list. OT_ERROR_INVALID_ARGS The port is invalid (value 0 is reserved for internal use). OT_ERROR_NOT_FOUND The port was not found in the unsecure port list.

otIp6SelectSourceAddress

otError otIp6SelectSourceAddress(
  otInstance *aInstance,
  otMessageInfo *aMessageInfo
)

This function perform OpenThread source address selection.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in,out] aMessageInfo A pointer to the message information.
Return Values	OT_ERROR_NONE Found a source address and is filled into mSockAddr of aMessageInfo. OT_ERROR_NOT_FOUND No source address was found and aMessageInfo is unchanged.

otIp6Send

otError otIp6Send(
  otInstance *aInstance,
  otMessage *aMessage
)

This function sends an IPv6 datagram via the Thread interface.

The caller transfers ownership of aMessage when making this call. OpenThread will free aMessage when processing is complete, including when a value other than OT_ERROR_NONE is returned.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aMessage A pointer to the message buffer containing the IPv6 datagram.
Return Values	OT_ERROR_NONE Successfully processed the message. OT_ERROR_DROP Message was well-formed but not fully processed due to packet processing rules. OT_ERROR_NO_BUFS Could not allocate necessary message buffers when processing the datagram. OT_ERROR_NO_ROUTE No route to host. OT_ERROR_INVALID_SOURCE_ADDRESS Source address is invalid, e.g. an anycast address or a multicast address. OT_ERROR_PARSE Encountered a malformed header when processing the message.

otIp6SetAddressCallback

void otIp6SetAddressCallback(
  otInstance *aInstance,
  otIp6AddressCallback aCallback,
  void *aCallbackContext
)

This function registers a callback to notify internal IPv6 address changes.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aCallback A pointer to a function that is called when an internal IPv6 address is added or removed. NULL to disable the callback. [in] aCallbackContext A pointer to application-specific context.

otIp6SetEnabled

otError otIp6SetEnabled(
  otInstance *aInstance,
  bool aEnabled
)

Brings the IPv6 interface up or down.

Call this to enable or disable IPv6 communication.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aEnabled TRUE to enable IPv6, FALSE otherwise.
Return Values	OT_ERROR_NONE Successfully brought the IPv6 interface up/down. OT_ERROR_INVALID_STATE IPv6 interface is not available since device is operating in raw-link mode (applicable only when OPENTHREAD_CONFIG_LINK_RAW_ENABLE feature is enabled).

otIp6SetMeshLocalIid

otError otIp6SetMeshLocalIid(
  otInstance *aInstance,
  const otIp6InterfaceIdentifier *aIid
)

This function sets the Mesh Local IID (for test purpose).

Only available when OPENTHREAD_CONFIG_REFERENCE_DEVICE_ENABLE is enabled.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aIid A pointer to the Mesh Local IID to set.
Return Values	OT_ERROR_NONE Successfully set the Mesh Local IID. OT_ERROR_INVALID_STATE Thread protocols are enabled.

otIp6SetMulticastPromiscuousEnabled

void otIp6SetMulticastPromiscuousEnabled(
  otInstance *aInstance,
  bool aEnabled
)

Enables or disables multicast promiscuous mode on the Thread interface.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aEnabled TRUE to enable Multicast Promiscuous mode, FALSE otherwise.

See also:
otIp6IsMulticastPromiscuousEnabled

otIp6SetReceiveCallback

void otIp6SetReceiveCallback(
  otInstance *aInstance,
  otIp6ReceiveCallback aCallback,
  void *aCallbackContext
)

This function registers a callback to provide received IPv6 datagrams.

By default, this callback does not pass Thread control traffic. See otIp6SetReceiveFilterEnabled() to change the Thread control traffic filter setting.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aCallback A pointer to a function that is called when an IPv6 datagram is received or NULL to disable the callback. [in] aCallbackContext A pointer to application-specific context.

See also:
otIp6IsReceiveFilterEnabled
otIp6SetReceiveFilterEnabled

otIp6SetReceiveFilterEnabled

void otIp6SetReceiveFilterEnabled(
  otInstance *aInstance,
  bool aEnabled
)

This function sets whether or not Thread control traffic is filtered out when delivering IPv6 datagrams via the callback specified in otIp6SetReceiveCallback().

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aEnabled TRUE if Thread control traffic is filtered out, FALSE otherwise.

See also:
otIp6SetReceiveCallback
otIsReceiveIp6FilterEnabled

otIp6SetSlaacEnabled

void otIp6SetSlaacEnabled(
  otInstance *aInstance,
  bool aEnabled
)

This function enables/disables the SLAAC module.

This function requires the build-time feature OPENTHREAD_CONFIG_IP6_SLAAC_ENABLE to be enabled.

When SLAAC module is enabled, SLAAC addresses (based on on-mesh prefixes in Network Data) are added to the interface. When SLAAC module is disabled any previously added SLAAC address is removed.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aEnabled TRUE to enable, FALSE to disable.

otIp6SetSlaacPrefixFilter

void otIp6SetSlaacPrefixFilter(
  otInstance *aInstance,
  otIp6SlaacPrefixFilter aFilter
)

This function sets the SLAAC module filter handler.

This function requires the build-time feature OPENTHREAD_CONFIG_IP6_SLAAC_ENABLE to be enabled.

The filter handler is called by SLAAC module when it is about to add a SLAAC address based on a prefix to decide whether the address should be added or not.

A NULL filter handler disables filtering and allows all SLAAC addresses to be added.

If this function is not called, the default filter used by SLAAC module will be NULL (filtering is disabled).

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aFilter A pointer to SLAAC prefix filter handler, or NULL to disable filtering.

otIp6SockAddrToString

void otIp6SockAddrToString(
  const otSockAddr *aSockAddr,
  char *aBuffer,
  uint16_t aSize
)

This function converts a given IPv6 socket address to a human-readable string.

The IPv6 socket address string is formatted as [address]:port where address is shown as 16 hex values separated by : and port is the port number in decimal format, for example "[%x:%x:...:%x]:%u".

If the resulting string does not fit in aBuffer (within its aSize characters), the string will be truncated but the outputted string is always null-terminated.

Details
Parameters	[in] aSockAddr A pointer to an IPv6 socket address (MUST NOT be NULL). [out] aBuffer A pointer to a char array to output the string (MUST NOT be NULL). [in] aSize The size of aBuffer (in bytes). Recommended to use OT_IP6_SOCK_ADDR_STRING_SIZE.

otIp6SubscribeMulticastAddress

otError otIp6SubscribeMulticastAddress(
  otInstance *aInstance,
  const otIp6Address *aAddress
)

Subscribes the Thread interface to a Network Interface Multicast Address.

The passed in instance aAddress will be copied by the Thread interface. The Thread interface only supports a fixed number of externally added multicast addresses. See OPENTHREAD_CONFIG_IP6_MAX_EXT_MCAST_ADDRS.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aAddress A pointer to an IP Address.
Return Values	OT_ERROR_NONE Successfully subscribed to the Network Interface Multicast Address. OT_ERROR_ALREADY The multicast address is already subscribed. OT_ERROR_INVALID_ARGS The IP Address indicated by aAddress is an invalid multicast address. OT_ERROR_REJECTED The IP Address indicated by aAddress is an internal multicast address. OT_ERROR_NO_BUFS The Network Interface is already storing the maximum allowed external multicast addresses.

otIp6UnsubscribeMulticastAddress

otError otIp6UnsubscribeMulticastAddress(
  otInstance *aInstance,
  const otIp6Address *aAddress
)

Unsubscribes the Thread interface to a Network Interface Multicast Address.

Details
Parameters	[in] aInstance A pointer to an OpenThread instance. [in] aAddress A pointer to an IP Address.
Return Values	OT_ERROR_NONE Successfully unsubscribed to the Network Interface Multicast Address. OT_ERROR_REJECTED The IP Address indicated by aAddress is an internal address. OT_ERROR_NOT_FOUND The IP Address indicated by aAddress was not found.

Macros

OT_IP6_ADDRESS_SIZE

 OT_IP6_ADDRESS_SIZE 16

Size of an IPv6 address (bytes)

OT_IP6_ADDRESS_STRING_SIZE

 OT_IP6_ADDRESS_STRING_SIZE 40

Recommended size for string representation of an IPv6 address.

OT_IP6_IID_SIZE

 OT_IP6_IID_SIZE 8

Size of an IPv6 Interface Identifier (bytes)

OT_IP6_MAX_MLR_ADDRESSES

 OT_IP6_MAX_MLR_ADDRESSES 15

Max number of IPv6 addresses supported by Multicast Listener Registration.

OT_IP6_PREFIX_BITSIZE

 OT_IP6_PREFIX_BITSIZE (OT_IP6_PREFIX_SIZE * 8)

Size of an IPv6 prefix (bits)

OT_IP6_PREFIX_SIZE

 OT_IP6_PREFIX_SIZE 8

Size of an IPv6 prefix (bytes)

OT_IP6_PREFIX_STRING_SIZE

 OT_IP6_PREFIX_STRING_SIZE 45

Recommended size for string representation of an IPv6 prefix.

OT_IP6_SOCK_ADDR_STRING_SIZE

 OT_IP6_SOCK_ADDR_STRING_SIZE 48

Recommended size for string representation of an IPv6 socket address.

Resources

OpenThread API Reference topics originate from the source code, available on GitHub. For more information, or to contribute to our documentation, refer to Resources.