https://github.com/torvalds/linux
Tip revision: 431c1646e1f86b949fa3685efc50b660a364c2b6 authored by Linus Torvalds on 01 September 2024, 07:46:02 UTC
Linux 6.11-rc6
Linux 6.11-rc6
Tip revision: 431c164
dccp.h
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _UAPI_LINUX_DCCP_H
#define _UAPI_LINUX_DCCP_H
#include <linux/types.h>
#include <asm/byteorder.h>
/**
* struct dccp_hdr - generic part of DCCP packet header
*
* @dccph_sport - Relevant port on the endpoint that sent this packet
* @dccph_dport - Relevant port on the other endpoint
* @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
* @dccph_ccval - Used by the HC-Sender CCID
* @dccph_cscov - Parts of the packet that are covered by the Checksum field
* @dccph_checksum - Internet checksum, depends on dccph_cscov
* @dccph_x - 0 = 24 bit sequence number, 1 = 48
* @dccph_type - packet type, see DCCP_PKT_ prefixed macros
* @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x
*/
struct dccp_hdr {
__be16 dccph_sport,
dccph_dport;
__u8 dccph_doff;
#if defined(__LITTLE_ENDIAN_BITFIELD)
__u8 dccph_cscov:4,
dccph_ccval:4;
#elif defined(__BIG_ENDIAN_BITFIELD)
__u8 dccph_ccval:4,
dccph_cscov:4;
#else
#error "Adjust your <asm/byteorder.h> defines"
#endif
__sum16 dccph_checksum;
#if defined(__LITTLE_ENDIAN_BITFIELD)
__u8 dccph_x:1,
dccph_type:4,
dccph_reserved:3;
#elif defined(__BIG_ENDIAN_BITFIELD)
__u8 dccph_reserved:3,
dccph_type:4,
dccph_x:1;
#else
#error "Adjust your <asm/byteorder.h> defines"
#endif
__u8 dccph_seq2;
__be16 dccph_seq;
};
/**
* struct dccp_hdr_ext - the low bits of a 48 bit seq packet
*
* @dccph_seq_low - low 24 bits of a 48 bit seq packet
*/
struct dccp_hdr_ext {
__be32 dccph_seq_low;
};
/**
* struct dccp_hdr_request - Connection initiation request header
*
* @dccph_req_service - Service to which the client app wants to connect
*/
struct dccp_hdr_request {
__be32 dccph_req_service;
};
/**
* struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
*
* @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
* @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
*/
struct dccp_hdr_ack_bits {
__be16 dccph_reserved1;
__be16 dccph_ack_nr_high;
__be32 dccph_ack_nr_low;
};
/**
* struct dccp_hdr_response - Connection initiation response header
*
* @dccph_resp_ack - 48 bit Acknowledgment Number Subheader (5.3)
* @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
*/
struct dccp_hdr_response {
struct dccp_hdr_ack_bits dccph_resp_ack;
__be32 dccph_resp_service;
};
/**
* struct dccp_hdr_reset - Unconditionally shut down a connection
*
* @dccph_reset_ack - 48 bit Acknowledgment Number Subheader (5.6)
* @dccph_reset_code - one of %dccp_reset_codes
* @dccph_reset_data - the Data 1 ... Data 3 fields from 5.6
*/
struct dccp_hdr_reset {
struct dccp_hdr_ack_bits dccph_reset_ack;
__u8 dccph_reset_code,
dccph_reset_data[3];
};
enum dccp_pkt_type {
DCCP_PKT_REQUEST = 0,
DCCP_PKT_RESPONSE,
DCCP_PKT_DATA,
DCCP_PKT_ACK,
DCCP_PKT_DATAACK,
DCCP_PKT_CLOSEREQ,
DCCP_PKT_CLOSE,
DCCP_PKT_RESET,
DCCP_PKT_SYNC,
DCCP_PKT_SYNCACK,
DCCP_PKT_INVALID,
};
#define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
static inline unsigned int dccp_packet_hdr_len(const __u8 type)
{
if (type == DCCP_PKT_DATA)
return 0;
if (type == DCCP_PKT_DATAACK ||
type == DCCP_PKT_ACK ||
type == DCCP_PKT_SYNC ||
type == DCCP_PKT_SYNCACK ||
type == DCCP_PKT_CLOSE ||
type == DCCP_PKT_CLOSEREQ)
return sizeof(struct dccp_hdr_ack_bits);
if (type == DCCP_PKT_REQUEST)
return sizeof(struct dccp_hdr_request);
if (type == DCCP_PKT_RESPONSE)
return sizeof(struct dccp_hdr_response);
return sizeof(struct dccp_hdr_reset);
}
enum dccp_reset_codes {
DCCP_RESET_CODE_UNSPECIFIED = 0,
DCCP_RESET_CODE_CLOSED,
DCCP_RESET_CODE_ABORTED,
DCCP_RESET_CODE_NO_CONNECTION,
DCCP_RESET_CODE_PACKET_ERROR,
DCCP_RESET_CODE_OPTION_ERROR,
DCCP_RESET_CODE_MANDATORY_ERROR,
DCCP_RESET_CODE_CONNECTION_REFUSED,
DCCP_RESET_CODE_BAD_SERVICE_CODE,
DCCP_RESET_CODE_TOO_BUSY,
DCCP_RESET_CODE_BAD_INIT_COOKIE,
DCCP_RESET_CODE_AGGRESSION_PENALTY,
DCCP_MAX_RESET_CODES /* Leave at the end! */
};
/* DCCP options */
enum {
DCCPO_PADDING = 0,
DCCPO_MANDATORY = 1,
DCCPO_MIN_RESERVED = 3,
DCCPO_MAX_RESERVED = 31,
DCCPO_CHANGE_L = 32,
DCCPO_CONFIRM_L = 33,
DCCPO_CHANGE_R = 34,
DCCPO_CONFIRM_R = 35,
DCCPO_NDP_COUNT = 37,
DCCPO_ACK_VECTOR_0 = 38,
DCCPO_ACK_VECTOR_1 = 39,
DCCPO_TIMESTAMP = 41,
DCCPO_TIMESTAMP_ECHO = 42,
DCCPO_ELAPSED_TIME = 43,
DCCPO_MAX = 45,
DCCPO_MIN_RX_CCID_SPECIFIC = 128, /* from sender to receiver */
DCCPO_MAX_RX_CCID_SPECIFIC = 191,
DCCPO_MIN_TX_CCID_SPECIFIC = 192, /* from receiver to sender */
DCCPO_MAX_TX_CCID_SPECIFIC = 255,
};
/* maximum size of a single TLV-encoded DCCP option (sans type/len bytes) */
#define DCCP_SINGLE_OPT_MAXLEN 253
/* DCCP CCIDS */
enum {
DCCPC_CCID2 = 2,
DCCPC_CCID3 = 3,
};
/* DCCP features (RFC 4340 section 6.4) */
enum dccp_feature_numbers {
DCCPF_RESERVED = 0,
DCCPF_CCID = 1,
DCCPF_SHORT_SEQNOS = 2,
DCCPF_SEQUENCE_WINDOW = 3,
DCCPF_ECN_INCAPABLE = 4,
DCCPF_ACK_RATIO = 5,
DCCPF_SEND_ACK_VECTOR = 6,
DCCPF_SEND_NDP_COUNT = 7,
DCCPF_MIN_CSUM_COVER = 8,
DCCPF_DATA_CHECKSUM = 9,
/* 10-127 reserved */
DCCPF_MIN_CCID_SPECIFIC = 128,
DCCPF_SEND_LEV_RATE = 192, /* RFC 4342, sec. 8.4 */
DCCPF_MAX_CCID_SPECIFIC = 255,
};
/* DCCP socket control message types for cmsg */
enum dccp_cmsg_type {
DCCP_SCM_PRIORITY = 1,
DCCP_SCM_QPOLICY_MAX = 0xFFFF,
/* ^-- Up to here reserved exclusively for qpolicy parameters */
DCCP_SCM_MAX
};
/* DCCP priorities for outgoing/queued packets */
enum dccp_packet_dequeueing_policy {
DCCPQ_POLICY_SIMPLE,
DCCPQ_POLICY_PRIO,
DCCPQ_POLICY_MAX
};
/* DCCP socket options */
#define DCCP_SOCKOPT_PACKET_SIZE 1 /* XXX deprecated, without effect */
#define DCCP_SOCKOPT_SERVICE 2
#define DCCP_SOCKOPT_CHANGE_L 3
#define DCCP_SOCKOPT_CHANGE_R 4
#define DCCP_SOCKOPT_GET_CUR_MPS 5
#define DCCP_SOCKOPT_SERVER_TIMEWAIT 6
#define DCCP_SOCKOPT_SEND_CSCOV 10
#define DCCP_SOCKOPT_RECV_CSCOV 11
#define DCCP_SOCKOPT_AVAILABLE_CCIDS 12
#define DCCP_SOCKOPT_CCID 13
#define DCCP_SOCKOPT_TX_CCID 14
#define DCCP_SOCKOPT_RX_CCID 15
#define DCCP_SOCKOPT_QPOLICY_ID 16
#define DCCP_SOCKOPT_QPOLICY_TXQLEN 17
#define DCCP_SOCKOPT_CCID_RX_INFO 128
#define DCCP_SOCKOPT_CCID_TX_INFO 192
/* maximum number of services provided on the same listening port */
#define DCCP_SERVICE_LIST_MAX_LEN 32
#endif /* _UAPI_LINUX_DCCP_H */