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

#ifndef __KERNEL__
#include <netinet/in.h>         /* for sockaddr_in and sockaddr_in6     */
#include <sys/socket.h>         /* for struct sockaddr                  */
#endif

#include <linux/const.h>
#include <linux/types.h>
#include <linux/in.h>           /* for sockaddr_in                      */
#include <linux/in6.h>          /* for sockaddr_in6                     */
#include <linux/socket.h>       /* for sockaddr_storage and sa_family   */

#define MPTCP_SUBFLOW_FLAG_MCAP_REM             _BITUL(0)
#define MPTCP_SUBFLOW_FLAG_MCAP_LOC             _BITUL(1)
#define MPTCP_SUBFLOW_FLAG_JOIN_REM             _BITUL(2)
#define MPTCP_SUBFLOW_FLAG_JOIN_LOC             _BITUL(3)
#define MPTCP_SUBFLOW_FLAG_BKUP_REM             _BITUL(4)
#define MPTCP_SUBFLOW_FLAG_BKUP_LOC             _BITUL(5)
#define MPTCP_SUBFLOW_FLAG_FULLY_ESTABLISHED    _BITUL(6)
#define MPTCP_SUBFLOW_FLAG_CONNECTED            _BITUL(7)
#define MPTCP_SUBFLOW_FLAG_MAPVALID             _BITUL(8)

#define MPTCP_PM_CMD_GRP_NAME   "mptcp_pm_cmds"
#define MPTCP_PM_EV_GRP_NAME    "mptcp_pm_events"

#include <linux/mptcp_pm.h>

#define MPTCP_INFO_FLAG_FALLBACK                _BITUL(0)
#define MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED     _BITUL(1)

#define MPTCP_PM_EV_FLAG_DENY_JOIN_ID0          _BITUL(0)
#define MPTCP_PM_EV_FLAG_SERVER_SIDE            _BITUL(1)

#define MPTCP_PM_ADDR_FLAG_SIGNAL               _BITUL(0)
#define MPTCP_PM_ADDR_FLAG_SUBFLOW              _BITUL(1)
#define MPTCP_PM_ADDR_FLAG_BACKUP               _BITUL(2)
#define MPTCP_PM_ADDR_FLAG_FULLMESH             _BITUL(3)
#define MPTCP_PM_ADDR_FLAG_IMPLICIT             _BITUL(4)
#define MPTCP_PM_ADDR_FLAG_LAMINAR              _BITUL(5)
#define MPTCP_PM_ADDR_FLAGS_MASK                GENMASK(5, 0)

struct mptcp_info {
        __u8    mptcpi_subflows;
        #define mptcpi_extra_subflows mptcpi_subflows
        __u8    mptcpi_add_addr_signal;
        __u8    mptcpi_add_addr_accepted;
        __u8    mptcpi_subflows_max;
        #define mptcpi_limit_extra_subflows mptcpi_subflows_max
        __u8    mptcpi_add_addr_signal_max;
        #define mptcpi_endp_signal_max mptcpi_add_addr_signal_max
        __u8    mptcpi_add_addr_accepted_max;
        #define mptcpi_limit_add_addr_accepted mptcpi_add_addr_accepted_max
        /* 16-bit hole that can no longer be filled */
        __u32   mptcpi_flags;
        __u32   mptcpi_token;
        __u64   mptcpi_write_seq;
        __u64   mptcpi_snd_una;
        __u64   mptcpi_rcv_nxt;
        __u8    mptcpi_local_addr_used;
        __u8    mptcpi_local_addr_max;
        #define mptcpi_endp_subflow_max mptcpi_local_addr_max
        __u8    mptcpi_csum_enabled;
        /* 8-bit hole that can no longer be filled */
        __u32   mptcpi_retransmits;
        __u64   mptcpi_bytes_retrans;
        __u64   mptcpi_bytes_sent;
        __u64   mptcpi_bytes_received;
        __u64   mptcpi_bytes_acked;
        __u8    mptcpi_subflows_total;
        __u8    mptcpi_endp_laminar_max;
        __u8    mptcpi_endp_fullmesh_max;
        __u8    reserved;
        __u32   mptcpi_last_data_sent;
        __u32   mptcpi_last_data_recv;
        __u32   mptcpi_last_ack_recv;
};

/* MPTCP Reset reason codes, rfc8684 */
#define MPTCP_RST_EUNSPEC       0
#define MPTCP_RST_EMPTCP        1
#define MPTCP_RST_ERESOURCE     2
#define MPTCP_RST_EPROHIBIT     3
#define MPTCP_RST_EWQ2BIG       4
#define MPTCP_RST_EBADPERF      5
#define MPTCP_RST_EMIDDLEBOX    6

struct mptcp_subflow_data {
        __u32           size_subflow_data;              /* size of this structure in userspace */
        __u32           num_subflows;                   /* must be 0, set by kernel */
        __u32           size_kernel;                    /* must be 0, set by kernel */
        __u32           size_user;                      /* size of one element in data[] */
} __attribute__((aligned(8)));

struct mptcp_subflow_addrs {
        union {
                __kernel_sa_family_t sa_family;
                struct sockaddr sa_local;
                struct sockaddr_in sin_local;
                struct sockaddr_in6 sin6_local;
                struct __kernel_sockaddr_storage ss_local;
        };
        union {
                struct sockaddr sa_remote;
                struct sockaddr_in sin_remote;
                struct sockaddr_in6 sin6_remote;
                struct __kernel_sockaddr_storage ss_remote;
        };
};

struct mptcp_subflow_info {
        __u32                           id;
        struct mptcp_subflow_addrs      addrs;
};

struct mptcp_full_info {
        __u32           size_tcpinfo_kernel;    /* must be 0, set by kernel */
        __u32           size_tcpinfo_user;
        __u32           size_sfinfo_kernel;     /* must be 0, set by kernel */
        __u32           size_sfinfo_user;
        __u32           num_subflows;           /* must be 0, set by kernel (real subflow count) */
        __u32           size_arrays_user;       /* max subflows that userspace is interested in;
                                                 * the buffers at subflow_info/tcp_info
                                                 * are respectively at least:
                                                 *  size_arrays * size_sfinfo_user
                                                 *  size_arrays * size_tcpinfo_user
                                                 * bytes wide
                                                 */
        __aligned_u64           subflow_info;
        __aligned_u64           tcp_info;
        struct mptcp_info       mptcp_info;
};

/* MPTCP socket options */
#define MPTCP_INFO              1
#define MPTCP_TCPINFO           2
#define MPTCP_SUBFLOW_ADDRS     3
#define MPTCP_FULL_INFO         4

#endif /* _UAPI_MPTCP_H */