Sctp.h

Go to the documentation of this file.

//
// Sctp
//
 
#ifndef __KINESIS_VIDEO_WEBRTC_CLIENT_SCTP_SCTP__
#define __KINESIS_VIDEO_WEBRTC_CLIENT_SCTP_SCTP__
 
#pragma once
 
#ifdef __cplusplus
extern "C" {
#endif
 
// 1200 - 12 (SCTP header Size)
#define SCTP_MTU                         1188
#define SCTP_MAX_STREAMS                 300 // outbound and inbound streams negotiated per association
#define SCTP_ASSOCIATION_DEFAULT_PORT    5000
#define SCTP_DCEP_HEADER_LENGTH          12
#define SCTP_DCEP_LABEL_LEN_OFFSET       8
#define SCTP_DCEP_LABEL_OFFSET           12
#define SCTP_MAX_ALLOWABLE_PACKET_LENGTH (SCTP_DCEP_HEADER_LENGTH + MAX_DATA_CHANNEL_NAME_LEN + MAX_DATA_CHANNEL_PROTOCOL_LEN + 2)
 
#define SCTP_SESSION_ACTIVE             0
#define SCTP_SESSION_SHUTDOWN_INITIATED 1
#define SCTP_SESSION_SHUTDOWN_COMPLETED 2
 
#define DEFAULT_SCTP_SHUTDOWN_TIMEOUT 2 * HUNDREDS_OF_NANOS_IN_A_SECOND
 
#define DEFAULT_USRSCTP_TEARDOWN_POLLING_INTERVAL (10 * HUNDREDS_OF_NANOS_IN_A_MILLISECOND)
 
#define SCTP_TIMER_INTERVAL    (100 * HUNDREDS_OF_NANOS_IN_A_MILLISECOND)
#define SCTP_TIMER_START_DELAY (100 * HUNDREDS_OF_NANOS_IN_A_MILLISECOND)
 
#define SCTP_CONTEXT_REFERENCE_WAIT_TIMEOUT (5 * HUNDREDS_OF_NANOS_IN_A_SECOND)
 
// Values taken from defaults suggested by RFC 9260 spec: https://www.ietf.org/rfc/rfc9260.pdf
 
// Max retransmits along a given single path. Typical default is 5
#define SCTP_MAX_PATH_RETRANSMITS 5
// Max retransmits across all paths for an endpoint association. Typical default is double max path retransmits
#define SCTP_MAX_ASSOCIATION_RETRANSMITS 10
// Retransmission timeout. Typical default is 60 seconds
#define SCTP_RTO_MAX 60000
 
enum { SCTP_PPID_DCEP = 50, SCTP_PPID_STRING = 51, SCTP_PPID_BINARY = 53, SCTP_PPID_STRING_EMPTY = 56, SCTP_PPID_BINARY_EMPTY = 57 };
 
enum {
    DCEP_DATA_CHANNEL_OPEN = 0x03,
    DCEP_DATA_CHANNEL_ACK = 0x02,
};
 
typedef enum {
    DCEP_DATA_CHANNEL_RELIABLE_ORDERED = (BYTE) 0x00,
    DCEP_DATA_CHANNEL_RELIABLE_UNORDERED = (BYTE) 0x80,
    DCEP_DATA_CHANNEL_REXMIT = (BYTE) 0x01,
    DCEP_DATA_CHANNEL_TIMED = (BYTE) 0x02
} DATA_CHANNEL_TYPE;
 
// Callback that is fired when SCTP Association wishes to send packet
typedef VOID (*SctpSessionOutboundPacketFunc)(UINT64, PBYTE, UINT32);
 
// Callback that is fired when SCTP has a new DataChannel
// Argument is ChannelID and ChannelName + Len. A failure means the channel was not taken: no DATA_CHANNEL_ACK is sent
typedef STATUS (*SctpSessionDataChannelOpenFunc)(UINT64, UINT32, PBYTE, UINT32, PRtcDataChannelInit);
 
// Callback that is fired when SCTP has a DataChannel Message.
// Argument is ChannelID and Message + Len
typedef VOID (*SctpSessionDataChannelMessageFunc)(UINT64, UINT32, BOOL, PBYTE, UINT32);
 
// Callback that is fired when SCTP receives a DATA_CHANNEL_ACK. Argument is ChannelID
typedef VOID (*SctpSessionDataChannelAckFunc)(UINT64, UINT32);

typedef struct SctpContext {
    // last time the periodic usrsctp timers were called
    UINT64 lastTickTime;
    volatile ATOMIC_BOOL isSctpInitialized;
    SIZE_T contextRefCnt;
    MUTEX sctpContextLock;
} SctpContext, *PSctpContext;
 
typedef struct {
    UINT64 customData;
    SctpSessionOutboundPacketFunc outboundPacketFunc;
    SctpSessionDataChannelOpenFunc dataChannelOpenFunc;
    SctpSessionDataChannelMessageFunc dataChannelMessageFunc;
    SctpSessionDataChannelAckFunc dataChannelAckFunc;
} SctpSessionCallbacks, *PSctpSessionCallbacks;
 
typedef struct {
    volatile SIZE_T shutdownStatus;
    struct socket* socket;
    struct sctp_sendv_spa spa;
    BYTE packet[SCTP_MAX_ALLOWABLE_PACKET_LENGTH];
    UINT32 packetSize;
    SctpSessionCallbacks sctpSessionCallbacks;
    TIMER_QUEUE_HANDLE timerQueueHandle;
    UINT32 timerTaskId;
} SctpSession, *PSctpSession;
 
STATUS initSctpSession();
VOID deinitSctpSession();
STATUS createSctpSession(PSctpSessionCallbacks, TIMER_QUEUE_HANDLE, PSctpSession*);
STATUS freeSctpSession(PSctpSession*);
STATUS putSctpPacket(PSctpSession, PBYTE, UINT32);
// The last BOOL sends ordered whatever the channel's setting: an in-band channel until its DATA_CHANNEL_ACK, RFC 8832 section 6
STATUS sctpSessionWriteMessage(PSctpSession, UINT32, BOOL, PBYTE, UINT32, PRtcDataChannelInit, BOOL);
VOID sctpSessionSetSendInfo(struct sctp_sendv_spa*, UINT32, BOOL, PRtcDataChannelInit, BOOL);
VOID dcepParseChannelParameters(PBYTE, PRtcDataChannelInit);
STATUS sctpSessionWriteDcep(PSctpSession, UINT32, PCHAR, UINT32, PRtcDataChannelInit);
STATUS handleDcepPacket(PSctpSession, UINT32, PBYTE, SIZE_T);
 
// Callbacks used by usrsctp
INT32 onSctpOutboundPacket(PVOID, PVOID, ULONG, UINT8, UINT8);
INT32 onSctpInboundPacket(struct socket*, union sctp_sockstore, PVOID, ULONG, struct sctp_rcvinfo, INT32, PVOID);
// Callback to drive periodic SCTP timers
STATUS sctpTimerCallback(UINT32, UINT64, UINT64);
 
#ifdef __cplusplus
}
#endif
#endif //__KINESIS_VIDEO_WEBRTC_CLIENT_SCTP_SCTP__