netlink.h

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/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _UAPI__LINUX_NETLINK_H
#define _UAPI__LINUX_NETLINK_H
 
#include <linux/const.h>
#include <linux/socket.h> /* for __kernel_sa_family_t */
#include <linux/types.h>
 
#define NETLINK_ROUTE       0   /* Routing/device hook              */
#define NETLINK_UNUSED      1   /* Unused number                */
#define NETLINK_USERSOCK    2   /* Reserved for user mode socket protocols  */
#define NETLINK_FIREWALL    3   /* Unused number, formerly ip_queue     */
#define NETLINK_SOCK_DIAG   4   /* socket monitoring                */
#define NETLINK_NFLOG       5   /* netfilter/iptables ULOG */
#define NETLINK_XFRM        6   /* ipsec */
#define NETLINK_SELINUX     7   /* SELinux event notifications */
#define NETLINK_ISCSI       8   /* Open-iSCSI */
#define NETLINK_AUDIT       9   /* auditing */
#define NETLINK_FIB_LOOKUP  10  
#define NETLINK_CONNECTOR   11
#define NETLINK_NETFILTER   12  /* netfilter subsystem */
#define NETLINK_IP6_FW      13
#define NETLINK_DNRTMSG     14  /* DECnet routing messages (obsolete) */
#define NETLINK_KOBJECT_UEVENT  15  /* Kernel messages to userspace */
#define NETLINK_GENERIC     16
/* leave room for NETLINK_DM (DM Events) */
#define NETLINK_SCSITRANSPORT   18  /* SCSI Transports */
#define NETLINK_ECRYPTFS    19
#define NETLINK_RDMA        20
#define NETLINK_CRYPTO      21  /* Crypto layer */
#define NETLINK_SMC     22  /* SMC monitoring */
 
#define NETLINK_INET_DIAG   NETLINK_SOCK_DIAG
 
#define MAX_LINKS 32        
 
struct sockaddr_nl {
    __kernel_sa_family_t    nl_family;  /* AF_NETLINK   */
    unsigned short  nl_pad;     /* zero     */
    __u32       nl_pid;     /* port ID  */
        __u32       nl_groups;  /* multicast groups mask */
};
 
struct nlmsghdr {
    __u32       nlmsg_len;
    __u16       nlmsg_type;
    __u16       nlmsg_flags;
    __u32       nlmsg_seq;
    __u32       nlmsg_pid;
};
 
/* Flags values */
 
#define NLM_F_REQUEST       0x01    /* It is request message.   */
#define NLM_F_MULTI     0x02    /* Multipart message, terminated by NLMSG_DONE */
#define NLM_F_ACK       0x04    /* Reply with ack, with zero or error code */
#define NLM_F_ECHO      0x08    /* Receive resulting notifications */
#define NLM_F_DUMP_INTR     0x10    /* Dump was inconsistent due to sequence change */
#define NLM_F_DUMP_FILTERED 0x20    /* Dump was filtered as requested */
 
/* Modifiers to GET request */
#define NLM_F_ROOT  0x100   /* specify tree root    */
#define NLM_F_MATCH 0x200   /* return all matching  */
#define NLM_F_ATOMIC    0x400   /* atomic GET       */
#define NLM_F_DUMP  (NLM_F_ROOT|NLM_F_MATCH)
 
/* Modifiers to NEW request */
#define NLM_F_REPLACE   0x100   /* Override existing        */
#define NLM_F_EXCL  0x200   /* Do not touch, if it exists   */
#define NLM_F_CREATE    0x400   /* Create, if it does not exist */
#define NLM_F_APPEND    0x800   /* Add to end of list       */
 
/* Modifiers to DELETE request */
#define NLM_F_NONREC    0x100   /* Do not delete recursively    */
#define NLM_F_BULK  0x200   /* Delete multiple objects  */
 
/* Flags for ACK message */
#define NLM_F_CAPPED    0x100   /* request was capped */
#define NLM_F_ACK_TLVS  0x200   /* extended ACK TVLs were included */
 
/*
   4.4BSD ADD       NLM_F_CREATE|NLM_F_EXCL
   4.4BSD CHANGE    NLM_F_REPLACE
 
   True CHANGE      NLM_F_CREATE|NLM_F_REPLACE
   Append       NLM_F_CREATE
   Check        NLM_F_EXCL
 */
 
#define NLMSG_ALIGNTO   4U
#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
#define NLMSG_HDRLEN     ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
#define NLMSG_LENGTH(len) ((len) + NLMSG_HDRLEN)
#define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
#define NLMSG_DATA(nlh)  ((void *)(((char *)nlh) + NLMSG_HDRLEN))
#define NLMSG_NEXT(nlh,len)  ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
                  (struct nlmsghdr *)(((char *)(nlh)) + \
                  NLMSG_ALIGN((nlh)->nlmsg_len)))
#define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
               (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
               (nlh)->nlmsg_len <= (len))
#define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
 
#define NLMSG_NOOP      0x1 /* Nothing.     */
#define NLMSG_ERROR     0x2 /* Error        */
#define NLMSG_DONE      0x3 /* End of a dump    */
#define NLMSG_OVERRUN       0x4 /* Data lost        */
 
#define NLMSG_MIN_TYPE      0x10    /* < 0x10: reserved control messages */
 
struct nlmsgerr {
    int     error;
    struct nlmsghdr msg;
    /*
     * followed by the message contents unless NETLINK_CAP_ACK was set
     * or the ACK indicates success (error == 0)
     * message length is aligned with NLMSG_ALIGN()
     */
    /*
     * followed by TLVs defined in enum nlmsgerr_attrs
     * if NETLINK_EXT_ACK was set
     */
};
 
enum nlmsgerr_attrs {
    NLMSGERR_ATTR_UNUSED,
    NLMSGERR_ATTR_MSG,
    NLMSGERR_ATTR_OFFS,
    NLMSGERR_ATTR_COOKIE,
    NLMSGERR_ATTR_POLICY,
    NLMSGERR_ATTR_MISS_TYPE,
    NLMSGERR_ATTR_MISS_NEST,
 
    __NLMSGERR_ATTR_MAX,
    NLMSGERR_ATTR_MAX = __NLMSGERR_ATTR_MAX - 1
};
 
#define NETLINK_ADD_MEMBERSHIP      1
#define NETLINK_DROP_MEMBERSHIP     2
#define NETLINK_PKTINFO         3
#define NETLINK_BROADCAST_ERROR     4
#define NETLINK_NO_ENOBUFS      5
#ifndef __KERNEL__
#define NETLINK_RX_RING         6
#define NETLINK_TX_RING         7
#endif
#define NETLINK_LISTEN_ALL_NSID     8
#define NETLINK_LIST_MEMBERSHIPS    9
#define NETLINK_CAP_ACK         10
#define NETLINK_EXT_ACK         11
#define NETLINK_GET_STRICT_CHK      12
 
struct nl_pktinfo {
    __u32   group;
};
 
struct nl_mmap_req {
    unsigned int    nm_block_size;
    unsigned int    nm_block_nr;
    unsigned int    nm_frame_size;
    unsigned int    nm_frame_nr;
};
 
struct nl_mmap_hdr {
    unsigned int    nm_status;
    unsigned int    nm_len;
    __u32       nm_group;
    /* credentials */
    __u32       nm_pid;
    __u32       nm_uid;
    __u32       nm_gid;
};
 
#ifndef __KERNEL__
enum nl_mmap_status {
    NL_MMAP_STATUS_UNUSED,
    NL_MMAP_STATUS_RESERVED,
    NL_MMAP_STATUS_VALID,
    NL_MMAP_STATUS_COPY,
    NL_MMAP_STATUS_SKIP,
};
 
#define NL_MMAP_MSG_ALIGNMENT       NLMSG_ALIGNTO
#define NL_MMAP_MSG_ALIGN(sz)       __ALIGN_KERNEL(sz, NL_MMAP_MSG_ALIGNMENT)
#define NL_MMAP_HDRLEN          NL_MMAP_MSG_ALIGN(sizeof(struct nl_mmap_hdr))
#endif
 
#define NET_MAJOR 36        /* Major 36 is reserved for networking                      */
 
enum {
    NETLINK_UNCONNECTED = 0,
    NETLINK_CONNECTED,
};
 
/*
 *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
 * +---------------------+- - -+- - - - - - - - - -+- - -+
 * |        Header       | Pad |     Payload       | Pad |
 * |   (struct nlattr)   | ing |                   | ing |
 * +---------------------+- - -+- - - - - - - - - -+- - -+
 *  <-------------- nlattr->nla_len -------------->
 */
 
struct nlattr {
    __u16           nla_len;
    __u16           nla_type;
};
 
/*
 * nla_type (16 bits)
 * +---+---+-------------------------------+
 * | N | O | Attribute Type                |
 * +---+---+-------------------------------+
 * N := Carries nested attributes
 * O := Payload stored in network byte order
 *
 * Note: The N and O flag are mutually exclusive.
 */
#define NLA_F_NESTED        (1 << 15)
#define NLA_F_NET_BYTEORDER (1 << 14)
#define NLA_TYPE_MASK       ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
 
#define NLA_ALIGNTO     4
#define NLA_ALIGN(len)      (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
#define NLA_HDRLEN      ((int) NLA_ALIGN(sizeof(struct nlattr)))
 
/* Generic 32 bitflags attribute content sent to the kernel.
 *
 * The value is a bitmap that defines the values being set
 * The selector is a bitmask that defines which value is legit
 *
 * Examples:
 *  value = 0x0, and selector = 0x1
 *  implies we are selecting bit 1 and we want to set its value to 0.
 *
 *  value = 0x2, and selector = 0x2
 *  implies we are selecting bit 2 and we want to set its value to 1.
 *
 */
struct nla_bitfield32 {
    __u32 value;
    __u32 selector;
};
 
/*
 * policy descriptions - it's specific to each family how this is used
 * Normally, it should be retrieved via a dump inside another attribute
 * specifying where it applies.
 */
 
enum netlink_attribute_type {
    NL_ATTR_TYPE_INVALID,
 
    NL_ATTR_TYPE_FLAG,
 
    NL_ATTR_TYPE_U8,
    NL_ATTR_TYPE_U16,
    NL_ATTR_TYPE_U32,
    NL_ATTR_TYPE_U64,
 
    NL_ATTR_TYPE_S8,
    NL_ATTR_TYPE_S16,
    NL_ATTR_TYPE_S32,
    NL_ATTR_TYPE_S64,
 
    NL_ATTR_TYPE_BINARY,
    NL_ATTR_TYPE_STRING,
    NL_ATTR_TYPE_NUL_STRING,
 
    NL_ATTR_TYPE_NESTED,
    NL_ATTR_TYPE_NESTED_ARRAY,
 
    NL_ATTR_TYPE_BITFIELD32,
 
    NL_ATTR_TYPE_SINT,
    NL_ATTR_TYPE_UINT,
};
 
enum netlink_policy_type_attr {
    NL_POLICY_TYPE_ATTR_UNSPEC,
    NL_POLICY_TYPE_ATTR_TYPE,
    NL_POLICY_TYPE_ATTR_MIN_VALUE_S,
    NL_POLICY_TYPE_ATTR_MAX_VALUE_S,
    NL_POLICY_TYPE_ATTR_MIN_VALUE_U,
    NL_POLICY_TYPE_ATTR_MAX_VALUE_U,
    NL_POLICY_TYPE_ATTR_MIN_LENGTH,
    NL_POLICY_TYPE_ATTR_MAX_LENGTH,
    NL_POLICY_TYPE_ATTR_POLICY_IDX,
    NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE,
    NL_POLICY_TYPE_ATTR_BITFIELD32_MASK,
    NL_POLICY_TYPE_ATTR_PAD,
    NL_POLICY_TYPE_ATTR_MASK,
 
    /* keep last */
    __NL_POLICY_TYPE_ATTR_MAX,
    NL_POLICY_TYPE_ATTR_MAX = __NL_POLICY_TYPE_ATTR_MAX - 1
};
 
#endif /* _UAPI__LINUX_NETLINK_H */