LXR linux/include/linux/netlink.h

   1#ifndef __LINUX_NETLINK_H
   2#define __LINUX_NETLINK_H
   3
   4#include <linux/socket.h> /* for __kernel_sa_family_t */
   5#include <linux/types.h>
   6
   7#define NETLINK_ROUTE           0       /* Routing/device hook                          */
   8#define NETLINK_UNUSED          1       /* Unused number                                */
   9#define NETLINK_USERSOCK        2       /* Reserved for user mode socket protocols      */
  10#define NETLINK_FIREWALL        3       /* Unused number, formerly ip_queue             */
  11#define NETLINK_SOCK_DIAG       4       /* socket monitoring                            */
  12#define NETLINK_NFLOG           5       /* netfilter/iptables ULOG */
  13#define NETLINK_XFRM            6       /* ipsec */
  14#define NETLINK_SELINUX         7       /* SELinux event notifications */
  15#define NETLINK_ISCSI           8       /* Open-iSCSI */
  16#define NETLINK_AUDIT           9       /* auditing */
  17#define NETLINK_FIB_LOOKUP      10      
  18#define NETLINK_CONNECTOR       11
  19#define NETLINK_NETFILTER       12      /* netfilter subsystem */
  20#define NETLINK_IP6_FW          13
  21#define NETLINK_DNRTMSG         14      /* DECnet routing messages */
  22#define NETLINK_KOBJECT_UEVENT  15      /* Kernel messages to userspace */
  23#define NETLINK_GENERIC         16
  24/* leave room for NETLINK_DM (DM Events) */
  25#define NETLINK_SCSITRANSPORT   18      /* SCSI Transports */
  26#define NETLINK_ECRYPTFS        19
  27#define NETLINK_RDMA            20
  28#define NETLINK_CRYPTO          21      /* Crypto layer */
  29
  30#define NETLINK_INET_DIAG       NETLINK_SOCK_DIAG
  31
  32#define MAX_LINKS 32            
  33
  34struct sockaddr_nl {
  35        __kernel_sa_family_t    nl_family;      /* AF_NETLINK   */
  36        unsigned short  nl_pad;         /* zero         */
  37        __u32           nl_pid;         /* port ID      */
  38        __u32           nl_groups;      /* multicast groups mask */
  39};
  40
  41struct nlmsghdr {
  42        __u32           nlmsg_len;      /* Length of message including header */
  43        __u16           nlmsg_type;     /* Message content */
  44        __u16           nlmsg_flags;    /* Additional flags */
  45        __u32           nlmsg_seq;      /* Sequence number */
  46        __u32           nlmsg_pid;      /* Sending process port ID */
  47};
  48
  49/* Flags values */
  50
  51#define NLM_F_REQUEST           1       /* It is request message.       */
  52#define NLM_F_MULTI             2       /* Multipart message, terminated by NLMSG_DONE */
  53#define NLM_F_ACK               4       /* Reply with ack, with zero or error code */
  54#define NLM_F_ECHO              8       /* Echo this request            */
  55#define NLM_F_DUMP_INTR         16      /* Dump was inconsistent due to sequence change */
  56
  57/* Modifiers to GET request */
  58#define NLM_F_ROOT      0x100   /* specify tree root    */
  59#define NLM_F_MATCH     0x200   /* return all matching  */
  60#define NLM_F_ATOMIC    0x400   /* atomic GET           */
  61#define NLM_F_DUMP      (NLM_F_ROOT|NLM_F_MATCH)
  62
  63/* Modifiers to NEW request */
  64#define NLM_F_REPLACE   0x100   /* Override existing            */
  65#define NLM_F_EXCL      0x200   /* Do not touch, if it exists   */
  66#define NLM_F_CREATE    0x400   /* Create, if it does not exist */
  67#define NLM_F_APPEND    0x800   /* Add to end of list           */
  68
  69/*
  70   4.4BSD ADD           NLM_F_CREATE|NLM_F_EXCL
  71   4.4BSD CHANGE        NLM_F_REPLACE
  72
  73   True CHANGE          NLM_F_CREATE|NLM_F_REPLACE
  74   Append               NLM_F_CREATE
  75   Check                NLM_F_EXCL
  76 */
  77
  78#define NLMSG_ALIGNTO   4U
  79#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
  80#define NLMSG_HDRLEN     ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
  81#define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
  82#define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
  83#define NLMSG_DATA(nlh)  ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
  84#define NLMSG_NEXT(nlh,len)      ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
  85                                  (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
  86#define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
  87                           (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
  88                           (nlh)->nlmsg_len <= (len))
  89#define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
  90
  91#define NLMSG_NOOP              0x1     /* Nothing.             */
  92#define NLMSG_ERROR             0x2     /* Error                */
  93#define NLMSG_DONE              0x3     /* End of a dump        */
  94#define NLMSG_OVERRUN           0x4     /* Data lost            */
  95
  96#define NLMSG_MIN_TYPE          0x10    /* < 0x10: reserved control messages */
  97
  98struct nlmsgerr {
  99        int             error;
 100        struct nlmsghdr msg;
 101};
 102
 103#define NETLINK_ADD_MEMBERSHIP  1
 104#define NETLINK_DROP_MEMBERSHIP 2
 105#define NETLINK_PKTINFO         3
 106#define NETLINK_BROADCAST_ERROR 4
 107#define NETLINK_NO_ENOBUFS      5
 108
 109struct nl_pktinfo {
 110        __u32   group;
 111};
 112
 113#define NET_MAJOR 36            /* Major 36 is reserved for networking                                          */
 114
 115enum {
 116        NETLINK_UNCONNECTED = 0,
 117        NETLINK_CONNECTED,
 118};
 119
 120/*
 121 *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
 122 * +---------------------+- - -+- - - - - - - - - -+- - -+
 123 * |        Header       | Pad |     Payload       | Pad |
 124 * |   (struct nlattr)   | ing |                   | ing |
 125 * +---------------------+- - -+- - - - - - - - - -+- - -+
 126 *  <-------------- nlattr->nla_len -------------->
 127 */
 128
 129struct nlattr {
 130        __u16           nla_len;
 131        __u16           nla_type;
 132};
 133
 134/*
 135 * nla_type (16 bits)
 136 * +---+---+-------------------------------+
 137 * | N | O | Attribute Type                |
 138 * +---+---+-------------------------------+
 139 * N := Carries nested attributes
 140 * O := Payload stored in network byte order
 141 *
 142 * Note: The N and O flag are mutually exclusive.
 143 */
 144#define NLA_F_NESTED            (1 << 15)
 145#define NLA_F_NET_BYTEORDER     (1 << 14)
 146#define NLA_TYPE_MASK           ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
 147
 148#define NLA_ALIGNTO             4
 149#define NLA_ALIGN(len)          (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
 150#define NLA_HDRLEN              ((int) NLA_ALIGN(sizeof(struct nlattr)))
 151
 152#ifdef __KERNEL__
 153
 154#include <linux/capability.h>
 155#include <linux/skbuff.h>
 156#include <linux/export.h>
 157
 158struct net;
 159
 160static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
 161{
 162        return (struct nlmsghdr *)skb->data;
 163}
 164
 165struct netlink_skb_parms {
 166        struct ucred            creds;          /* Skb credentials      */
 167        __u32                   pid;
 168        __u32                   dst_group;
 169};
 170
 171#define NETLINK_CB(skb)         (*(struct netlink_skb_parms*)&((skb)->cb))
 172#define NETLINK_CREDS(skb)      (&NETLINK_CB((skb)).creds)
 173
 174
 175extern void netlink_table_grab(void);
 176extern void netlink_table_ungrab(void);
 177
 178/* optional Netlink kernel configuration parameters */
 179struct netlink_kernel_cfg {
 180        unsigned int    groups;
 181        void            (*input)(struct sk_buff *skb);
 182        struct mutex    *cb_mutex;
 183        void            (*bind)(int group);
 184};
 185
 186extern struct sock *netlink_kernel_create(struct net *net, int unit,
 187                                          struct module *module,
 188                                          struct netlink_kernel_cfg *cfg);
 189extern void netlink_kernel_release(struct sock *sk);
 190extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
 191extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
 192extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
 193extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
 194extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
 195extern int netlink_has_listeners(struct sock *sk, unsigned int group);
 196extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
 197extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
 198                             __u32 group, gfp_t allocation);
 199extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
 200        __u32 pid, __u32 group, gfp_t allocation,
 201        int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
 202        void *filter_data);
 203extern int netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
 204extern int netlink_register_notifier(struct notifier_block *nb);
 205extern int netlink_unregister_notifier(struct notifier_block *nb);
 206
 207/* finegrained unicast helpers: */
 208struct sock *netlink_getsockbyfilp(struct file *filp);
 209int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
 210                      long *timeo, struct sock *ssk);
 211void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
 212int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
 213
 214/*
 215 *      skb should fit one page. This choice is good for headerless malloc.
 216 *      But we should limit to 8K so that userspace does not have to
 217 *      use enormous buffer sizes on recvmsg() calls just to avoid
 218 *      MSG_TRUNC when PAGE_SIZE is very large.
 219 */
 220#if PAGE_SIZE < 8192UL
 221#define NLMSG_GOODSIZE  SKB_WITH_OVERHEAD(PAGE_SIZE)
 222#else
 223#define NLMSG_GOODSIZE  SKB_WITH_OVERHEAD(8192UL)
 224#endif
 225
 226#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
 227
 228
 229struct netlink_callback {
 230        struct sk_buff          *skb;
 231        const struct nlmsghdr   *nlh;
 232        int                     (*dump)(struct sk_buff * skb,
 233                                        struct netlink_callback *cb);
 234        int                     (*done)(struct netlink_callback *cb);
 235        void                    *data;
 236        /* the module that dump function belong to */
 237        struct module           *module;
 238        u16                     family;
 239        u16                     min_dump_alloc;
 240        unsigned int            prev_seq, seq;
 241        long                    args[6];
 242};
 243
 244struct netlink_notify {
 245        struct net *net;
 246        int pid;
 247        int protocol;
 248};
 249
 250struct nlmsghdr *
 251__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags);
 252
 253struct netlink_dump_control {
 254        int (*dump)(struct sk_buff *skb, struct netlink_callback *);
 255        int (*done)(struct netlink_callback *);
 256        void *data;
 257        struct module *module;
 258        u16 min_dump_alloc;
 259};
 260
 261extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 262                                const struct nlmsghdr *nlh,
 263                                struct netlink_dump_control *control);
 264static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 265                                     const struct nlmsghdr *nlh,
 266                                     struct netlink_dump_control *control)
 267{
 268        if (!control->module)
 269                control->module = THIS_MODULE;
 270
 271        return __netlink_dump_start(ssk, skb, nlh, control);
 272}
 273
 274
 275#define NL_NONROOT_RECV 0x1
 276#define NL_NONROOT_SEND 0x2
 277extern void netlink_set_nonroot(int protocol, unsigned flag);
 278
 279#endif /* __KERNEL__ */
 280
 281#endif  /* __LINUX_NETLINK_H */
 282