LXR linux/include/linux/netlink.h

   1#ifndef __LINUX_NETLINK_H
   2#define __LINUX_NETLINK_H
   3
   4#include <linux/socket.h> /* for 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       /* Firewalling hook                             */
  11#define NETLINK_INET_DIAG       4       /* INET 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
  28#define MAX_LINKS 32            
  29
  30struct net;
  31
  32struct sockaddr_nl
  33{
  34        sa_family_t     nl_family;      /* AF_NETLINK   */
  35        unsigned short  nl_pad;         /* zero         */
  36        __u32           nl_pid;         /* port ID      */
  37        __u32           nl_groups;      /* multicast groups mask */
  38};
  39
  40struct nlmsghdr
  41{
  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
  56/* Modifiers to GET request */
  57#define NLM_F_ROOT      0x100   /* specify tree root    */
  58#define NLM_F_MATCH     0x200   /* return all matching  */
  59#define NLM_F_ATOMIC    0x400   /* atomic GET           */
  60#define NLM_F_DUMP      (NLM_F_ROOT|NLM_F_MATCH)
  61
  62/* Modifiers to NEW request */
  63#define NLM_F_REPLACE   0x100   /* Override existing            */
  64#define NLM_F_EXCL      0x200   /* Do not touch, if it exists   */
  65#define NLM_F_CREATE    0x400   /* Create, if it does not exist */
  66#define NLM_F_APPEND    0x800   /* Add to end of list           */
  67
  68/*
  69   4.4BSD ADD           NLM_F_CREATE|NLM_F_EXCL
  70   4.4BSD CHANGE        NLM_F_REPLACE
  71
  72   True CHANGE          NLM_F_CREATE|NLM_F_REPLACE
  73   Append               NLM_F_CREATE
  74   Check                NLM_F_EXCL
  75 */
  76
  77#define NLMSG_ALIGNTO   4
  78#define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
  79#define NLMSG_HDRLEN     ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
  80#define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(NLMSG_HDRLEN))
  81#define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
  82#define NLMSG_DATA(nlh)  ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
  83#define NLMSG_NEXT(nlh,len)      ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
  84                                  (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
  85#define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
  86                           (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
  87                           (nlh)->nlmsg_len <= (len))
  88#define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
  89
  90#define NLMSG_NOOP              0x1     /* Nothing.             */
  91#define NLMSG_ERROR             0x2     /* Error                */
  92#define NLMSG_DONE              0x3     /* End of a dump        */
  93#define NLMSG_OVERRUN           0x4     /* Data lost            */
  94
  95#define NLMSG_MIN_TYPE          0x10    /* < 0x10: reserved control messages */
  96
  97struct nlmsgerr
  98{
  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
 107struct nl_pktinfo
 108{
 109        __u32   group;
 110};
 111
 112#define NET_MAJOR 36            /* Major 36 is reserved for networking                                          */
 113
 114enum {
 115        NETLINK_UNCONNECTED = 0,
 116        NETLINK_CONNECTED,
 117};
 118
 119/*
 120 *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
 121 * +---------------------+- - -+- - - - - - - - - -+- - -+
 122 * |        Header       | Pad |     Payload       | Pad |
 123 * |   (struct nlattr)   | ing |                   | ing |
 124 * +---------------------+- - -+- - - - - - - - - -+- - -+
 125 *  <-------------- nlattr->nla_len -------------->
 126 */
 127
 128struct nlattr
 129{
 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
 157static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
 158{
 159        return (struct nlmsghdr *)skb->data;
 160}
 161
 162struct netlink_skb_parms
 163{
 164        struct ucred            creds;          /* Skb credentials      */
 165        __u32                   pid;
 166        __u32                   dst_group;
 167        kernel_cap_t            eff_cap;
 168        __u32                   loginuid;       /* Login (audit) uid */
 169        __u32                   sessionid;      /* Session id (audit) */
 170        __u32                   sid;            /* SELinux security id */
 171};
 172
 173#define NETLINK_CB(skb)         (*(struct netlink_skb_parms*)&((skb)->cb))
 174#define NETLINK_CREDS(skb)      (&NETLINK_CB((skb)).creds)
 175
 176
 177extern struct sock *netlink_kernel_create(struct net *net,
 178                                          int unit,unsigned int groups,
 179                                          void (*input)(struct sk_buff *skb),
 180                                          struct mutex *cb_mutex,
 181                                          struct module *module);
 182extern void netlink_kernel_release(struct sock *sk);
 183extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
 184extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
 185extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
 186extern int netlink_has_listeners(struct sock *sk, unsigned int group);
 187extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
 188extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
 189                             __u32 group, gfp_t allocation);
 190extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
 191extern int netlink_register_notifier(struct notifier_block *nb);
 192extern int netlink_unregister_notifier(struct notifier_block *nb);
 193
 194/* finegrained unicast helpers: */
 195struct sock *netlink_getsockbyfilp(struct file *filp);
 196int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
 197                      long *timeo, struct sock *ssk);
 198void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
 199int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
 200
 201/*
 202 *      skb should fit one page. This choice is good for headerless malloc.
 203 *      But we should limit to 8K so that userspace does not have to
 204 *      use enormous buffer sizes on recvmsg() calls just to avoid
 205 *      MSG_TRUNC when PAGE_SIZE is very large.
 206 */
 207#if PAGE_SIZE < 8192UL
 208#define NLMSG_GOODSIZE  SKB_WITH_OVERHEAD(PAGE_SIZE)
 209#else
 210#define NLMSG_GOODSIZE  SKB_WITH_OVERHEAD(8192UL)
 211#endif
 212
 213#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
 214
 215
 216struct netlink_callback
 217{
 218        struct sk_buff  *skb;
 219        struct nlmsghdr *nlh;
 220        int             (*dump)(struct sk_buff * skb, struct netlink_callback *cb);
 221        int             (*done)(struct netlink_callback *cb);
 222        int             family;
 223        long            args[6];
 224};
 225
 226struct netlink_notify
 227{
 228        struct net *net;
 229        int pid;
 230        int protocol;
 231};
 232
 233static __inline__ struct nlmsghdr *
 234__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)
 235{
 236        struct nlmsghdr *nlh;
 237        int size = NLMSG_LENGTH(len);
 238
 239        nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
 240        nlh->nlmsg_type = type;
 241        nlh->nlmsg_len = size;
 242        nlh->nlmsg_flags = flags;
 243        nlh->nlmsg_pid = pid;
 244        nlh->nlmsg_seq = seq;
 245        memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
 246        return nlh;
 247}
 248
 249#define NLMSG_NEW(skb, pid, seq, type, len, flags) \
 250({      if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \
 251                goto nlmsg_failure; \
 252        __nlmsg_put(skb, pid, seq, type, len, flags); })
 253
 254#define NLMSG_PUT(skb, pid, seq, type, len) \
 255        NLMSG_NEW(skb, pid, seq, type, len, 0)
 256
 257extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 258                              struct nlmsghdr *nlh,
 259                              int (*dump)(struct sk_buff *skb, struct netlink_callback*),
 260                              int (*done)(struct netlink_callback*));
 261
 262
 263#define NL_NONROOT_RECV 0x1
 264#define NL_NONROOT_SEND 0x2
 265extern void netlink_set_nonroot(int protocol, unsigned flag);
 266
 267#endif /* __KERNEL__ */
 268
 269#endif  /* __LINUX_NETLINK_H */
 270