/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef _LINUX_DCCP_H #define _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 /* _LINUX_DCCP_H */