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_SKIP            1       /* Reserved for ENskip                          */
   9 #define NETLINK_USERSOCK        2       /* Reserved for user mode socket protocols      */
  10 #define NETLINK_FIREWALL        3       /* Firewalling hook                             */
  11 #define NETLINK_TCPDIAG         4       /* TCP 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_ARPD            8
  16 #define NETLINK_AUDIT           9       /* auditing */
  17 #define NETLINK_ROUTE6          11      /* af_inet6 route comm channel */
  18 #define NETLINK_IP6_FW          13
  19 #define NETLINK_DNRTMSG         14      /* DECnet routing messages */
  20 #define NETLINK_TAPBASE         16      /* 16 to 31 are ethertap */
  21
  22 #define MAX_LINKS 32
  23
  24 struct sockaddr_nl
  25 {
  26         sa_family_t     nl_family;      /* AF_NETLINK   */
  27         unsigned short  nl_pad;         /* zero         */
  28         __u32           nl_pid;         /* process pid  */
  29         __u32           nl_groups;      /* multicast groups mask */
  30 };
  31
  32 struct nlmsghdr
  33 {
  34         __u32           nlmsg_len;      /* Length of message including header */
  35         __u16           nlmsg_type;     /* Message content */
  36         __u16           nlmsg_flags;    /* Additional flags */
  37         __u32           nlmsg_seq;      /* Sequence number */
  38         __u32           nlmsg_pid;      /* Sending process PID */
  39 };
  40
  41 /* Flags values */
  42
  43 #define NLM_F_REQUEST           1       /* It is request message.       */
  44 #define NLM_F_MULTI             2       /* Multipart message, terminated by NLMSG_DONE */
  45 #define NLM_F_ACK               4       /* Reply with ack, with zero or error code */
  46 #define NLM_F_ECHO              8       /* Echo this request            */
  47
  48 /* Modifiers to GET request */
  49 #define NLM_F_ROOT      0x100   /* specify tree root    */
  50 #define NLM_F_MATCH     0x200   /* return all matching  */
  51 #define NLM_F_ATOMIC    0x400   /* atomic GET           */
  52 #define NLM_F_DUMP      (NLM_F_ROOT|NLM_F_MATCH)
  53
  54 /* Modifiers to NEW request */
  55 #define NLM_F_REPLACE   0x100   /* Override existing            */
  56 #define NLM_F_EXCL      0x200   /* Do not touch, if it exists   */
  57 #define NLM_F_CREATE    0x400   /* Create, if it does not exist */
  58 #define NLM_F_APPEND    0x800   /* Add to end of list           */
  59
  60 /*
  61    4.4BSD ADD           NLM_F_CREATE|NLM_F_EXCL
  62    4.4BSD CHANGE        NLM_F_REPLACE
  63
  64    True CHANGE          NLM_F_CREATE|NLM_F_REPLACE
  65    Append               NLM_F_CREATE
  66    Check                NLM_F_EXCL
  67  */
  68
  69 #define NLMSG_ALIGNTO   4
  70 #define NLMSG_ALIGN(len) ( ((len)+NLMSG_ALIGNTO-1) & ~(NLMSG_ALIGNTO-1) )
  71 #define NLMSG_LENGTH(len) ((len)+NLMSG_ALIGN(sizeof(struct nlmsghdr)))
  72 #define NLMSG_SPACE(len) NLMSG_ALIGN(NLMSG_LENGTH(len))
  73 #define NLMSG_DATA(nlh)  ((void*)(((char*)nlh) + NLMSG_LENGTH(0)))
  74 #define NLMSG_NEXT(nlh,len)      ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \
  75                                   (struct nlmsghdr*)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))
  76 #define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \
  77                            (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \
  78                            (nlh)->nlmsg_len <= (len))
  79 #define NLMSG_PAYLOAD(nlh,len) ((nlh)->nlmsg_len - NLMSG_SPACE((len)))
  80
  81 #define NLMSG_NOOP              0x1     /* Nothing.             */
  82 #define NLMSG_ERROR             0x2     /* Error                */
  83 #define NLMSG_DONE              0x3     /* End of a dump        */
  84 #define NLMSG_OVERRUN           0x4     /* Data lost            */
  85
  86 struct nlmsgerr
  87 {
  88         int             error;
  89         struct nlmsghdr msg;
  90 };
  91
  92 #define NET_MAJOR 36            /* Major 36 is reserved for networking                                          */
  93
  94 enum {
  95         NETLINK_UNCONNECTED = 0,
  96         NETLINK_CONNECTED,
  97 };
  98
  99 #ifdef __KERNEL__
 100
 101 #include <linux/capability.h>
 102 #include <linux/skbuff.h>
 103
 104 struct netlink_skb_parms
 105 {
 106         struct ucred            creds;          /* Skb credentials      */
 107         __u32                   pid;
 108         __u32                   groups;
 109         __u32                   dst_pid;
 110         __u32                   dst_groups;
 111         kernel_cap_t            eff_cap;
 112 };
 113
 114 #define NETLINK_CB(skb)         (*(struct netlink_skb_parms*)&((skb)->cb))
 115 #define NETLINK_CREDS(skb)      (&NETLINK_CB((skb)).creds)
 116
 117
 118 extern int netlink_attach(int unit, int (*function)(int,struct sk_buff *skb));
 119 extern void netlink_detach(int unit);
 120 extern int netlink_post(int unit, struct sk_buff *skb);
 121 extern struct sock *netlink_kernel_create(int unit, void (*input)(struct sock *sk, int len));
 122 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
 123 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock);
 124 extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid,
 125                              __u32 group, int allocation);
 126 extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code);
 127 extern int netlink_register_notifier(struct notifier_block *nb);
 128 extern int netlink_unregister_notifier(struct notifier_block *nb);
 129
 130 /* finegrained unicast helpers: */
 131 struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid);
 132 struct sock *netlink_getsockbyfilp(struct file *filp);
 133 int netlink_attachskb(struct sock *sk, struct sk_buff *skb, int nonblock, long timeo);
 134 void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
 135 int netlink_sendskb(struct sock *sk, struct sk_buff *skb, int protocol);
 136
 137 /*
 138  *      skb should fit one page. This choice is good for headerless malloc.
 139  *
 140  *      FIXME: What is the best size for SLAB???? --ANK
 141  */
 142 #define NLMSG_GOODSIZE (PAGE_SIZE - ((sizeof(struct sk_buff)+0xF)&~0xF))
 143
 144
 145 struct netlink_callback
 146 {
 147         struct sk_buff  *skb;
 148         struct nlmsghdr *nlh;
 149         int             (*dump)(struct sk_buff * skb, struct netlink_callback *cb);
 150         int             (*done)(struct netlink_callback *cb);
 151         int             family;
 152         long            args[4];
 153 };
 154
 155 struct netlink_notify
 156 {
 157         int pid;
 158         int protocol;
 159 };
 160
 161 static __inline__ struct nlmsghdr *
 162 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len)
 163 {
 164         struct nlmsghdr *nlh;
 165         int size = NLMSG_LENGTH(len);
 166
 167         nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
 168         nlh->nlmsg_type = type;
 169         nlh->nlmsg_len = size;
 170         nlh->nlmsg_flags = 0;
 171         nlh->nlmsg_pid = pid;
 172         nlh->nlmsg_seq = seq;
 173         return nlh;
 174 }
 175
 176 #define NLMSG_PUT(skb, pid, seq, type, len) \
 177 ({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) goto nlmsg_failure; \
 178    __nlmsg_put(skb, pid, seq, type, len); })
 179
 180 extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 181                               struct nlmsghdr *nlh,
 182                               int (*dump)(struct sk_buff *skb, struct netlink_callback*),
 183                               int (*done)(struct netlink_callback*));
 184
 185
 186 #define NL_NONROOT_RECV 0x1
 187 #define NL_NONROOT_SEND 0x2
 188 extern void netlink_set_nonroot(int protocol, unsigned flag);
 189
 190 #endif /* __KERNEL__ */
 191
 192 #endif  /* __LINUX_NETLINK_H */