include/linux/netlink.h

   1 #ifndef __LINUX_NETLINK_H
   2 #define __LINUX_NETLINK_H
   3
   4 #define NETLINK_ROUTE           0       /* Routing/device hook                          */
   5 #define NETLINK_SKIP            1       /* Reserved for ENskip                          */
   6 #define NETLINK_USERSOCK        2       /* Reserved for user mode socket protocols      */
   7 #define NETLINK_FIREWALL        3       /* Firewalling hook                             */
   8 #define NETLINK_ARPD            8
   9 #define NETLINK_ROUTE6          11      /* af_inet6 route comm channel */
  10 #define NETLINK_IP6_FW          13
  11 #define NETLINK_DNRTMSG         14      /* DECnet routing messages */
  12 #define NETLINK_TAPBASE         16      /* 16 to 31 are ethertap */
  13
  14 #define MAX_LINKS 32
  15
  16 struct sockaddr_nl
  17 {
  18         sa_family_t     nl_family;      /* AF_NETLINK   */
  19         unsigned short  nl_pad;         /* zero         */
  20         __u32           nl_pid;         /* process pid  */
  21         __u32           nl_groups;      /* multicast groups mask */
  22 };
  23
  24 struct nlmsghdr
  25 {
  26         __u32           nlmsg_len;      /* Length of message including header */
  27         __u16           nlmsg_type;     /* Message content */
  28         __u16           nlmsg_flags;    /* Additional flags */
  29         __u32           nlmsg_seq;      /* Sequence number */
  30         __u32           nlmsg_pid;      /* Sending process PID */
  31 };
  32
  33 /* Flags values */
  34
  35 #define NLM_F_REQUEST           1       /* It is request message.       */
  36 #define NLM_F_MULTI             2       /* Multipart message, terminated by NLMSG_DONE */
  37 #define NLM_F_ACK               4       /* If succeed, reply with ack   */
  38 #define NLM_F_ECHO              8       /* Echo this request            */
  39
  40 /* Modifiers to GET request */
  41 #define NLM_F_ROOT      0x100   /* specify tree root    */
  42 #define NLM_F_MATCH     0x200   /* return all matching  */
  43 #define NLM_F_ATOMIC    0x400   /* atomic GET           */
  44 #define NLM_F_DUMP      (NLM_F_ROOT|NLM_F_MATCH)
  45
  46 /* Modifiers to NEW request */
  47 #define NLM_F_REPLACE   0x100   /* Override existing            */
  48 #define NLM_F_EXCL      0x200   /* Do not touch, if it exists   */
  49 #define NLM_F_CREATE    0x400   /* Create, if it does not exist */
  50 #define NLM_F_APPEND    0x800   /* Add to end of list           */
  51
  52 /*
  53    4.4BSD ADD           NLM_F_CREATE|NLM_F_EXCL
  54    4.4BSD CHANGE        NLM_F_REPLACE
  55
  56    True CHANGE          NLM_F_CREATE|NLM_F_REPLACE
  57    Append               NLM_F_CREATE
  58    Check                NLM_F_EXCL
  59  */
  60
  61 #define NLMSG_ALIGNTO   4
  62 #define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
  63 #define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(sizeof(struct nlmsghdr)))
  64 #define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
  65 #define NLMSG_DATA(nlh)  ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
  66 #define NLMSG_NEXT(nlh,len)      ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
  67                                   (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
  68 #define NLMSG_OK(nlh,len) ((len) > 0 && (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
  69                            (nlh)->nlmsg_len <= (len))
  70 #define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
  71
  72 #define NLMSG_NOOP              0x1     /* Nothing.             */
  73 #define NLMSG_ERROR             0x2     /* Error                */
  74 #define NLMSG_DONE              0x3     /* End of a dump        */
  75 #define NLMSG_OVERRUN           0x4     /* Data lost            */
  76
  77 struct nlmsgerr
  78 {
  79         int             error;
  80         struct nlmsghdr msg;
  81 };
  82
  83 #define NET_MAJOR 36            /* Major 36 is reserved for networking                                          */
  84
  85 #ifdef __KERNEL__
  86
  87 struct netlink_skb_parms
  88 {
  89         struct ucred            creds;          /* Skb credentials      */
  90         __u32                   pid;
  91         __u32                   groups;
  92         __u32                   dst_pid;
  93         __u32                   dst_groups;
  94         kernel_cap_t            eff_cap;
  95 };
  96
  97 #define NETLINK_CB(skb)         (*(struct netlink_skb_parms*)&((skb)->cb))
  98 #define NETLINK_CREDS(skb)      (&NETLINK_CB((skb)).creds)
  99
 100
 101 extern int netlink_attach(int unit, int (*function)(int,struct sk_buff *skb));
 102 extern void netlink_detach(int unit);
 103 extern int netlink_post(int unit, struct sk_buff *skb);
 104 extern int init_netlink(void);
 105 extern struct sock *netlink_kernel_create(int unit, void (*input)(struct sock *sk, int len));
 106 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
 107 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
 108 extern void netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
 109                               __u32 group, int allocation);
 110 extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
 111
 112 /*
 113  *      skb should fit one page. This choice is good for headerless malloc.
 114  *
 115  *      FIXME: What is the best size for SLAB???? --ANK
 116  */
 117 #define NLMSG_GOODSIZE (PAGE_SIZE - ((sizeof(struct sk_buff)+0xF)&~0xF))
 118
 119
 120 struct netlink_callback
 121 {
 122         struct sk_buff  *skb;
 123         struct nlmsghdr *nlh;
 124         int             (*dump)(struct sk_buff * skb, struct netlink_callback *cb);
 125         int             (*done)(struct netlink_callback *cb);
 126         int             family;
 127         long            args[4];
 128 };
 129
 130 extern __inline__ struct nlmsghdr *
 131 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len)
 132 {
 133         struct nlmsghdr *nlh;
 134         int size = NLMSG_LENGTH(len);
 135
 136         nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
 137         nlh->nlmsg_type = type;
 138         nlh->nlmsg_len = size;
 139         nlh->nlmsg_flags = 0;
 140         nlh->nlmsg_pid = pid;
 141         nlh->nlmsg_seq = seq;
 142         return nlh;
 143 }
 144
 145 #define NLMSG_PUT(skb, pid, seq, type, len) \
 146 ({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) goto nlmsg_failure; \
 147    __nlmsg_put(skb, pid, seq, type, len); })
 148
 149 extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 150                               struct nlmsghdr *nlh,
 151                               int (*dump)(struct sk_buff *skb, struct netlink_callback*),
 152                               int (*done)(struct netlink_callback*));
 153
 154
 155 #endif /* __KERNEL__ */
 156
 157 #endif  /* __LINUX_NETLINK_H */