netlink.h revision c40bba6922b470c0fd0c7a7b8b09584527c468e9
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#define NETLINK_BROADCAST_ERROR 4 107#define NETLINK_NO_ENOBUFS 5 108 109struct nl_pktinfo 110{ 111 __u32 group; 112}; 113 114#define NET_MAJOR 36 /* Major 36 is reserved for networking */ 115 116enum { 117 NETLINK_UNCONNECTED = 0, 118 NETLINK_CONNECTED, 119}; 120 121/* 122 * <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)--> 123 * +---------------------+- - -+- - - - - - - - - -+- - -+ 124 * | Header | Pad | Payload | Pad | 125 * | (struct nlattr) | ing | | ing | 126 * +---------------------+- - -+- - - - - - - - - -+- - -+ 127 * <-------------- nlattr->nla_len --------------> 128 */ 129 130struct nlattr 131{ 132 __u16 nla_len; 133 __u16 nla_type; 134}; 135 136/* 137 * nla_type (16 bits) 138 * +---+---+-------------------------------+ 139 * | N | O | Attribute Type | 140 * +---+---+-------------------------------+ 141 * N := Carries nested attributes 142 * O := Payload stored in network byte order 143 * 144 * Note: The N and O flag are mutually exclusive. 145 */ 146#define NLA_F_NESTED (1 << 15) 147#define NLA_F_NET_BYTEORDER (1 << 14) 148#define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER) 149 150#define NLA_ALIGNTO 4 151#define NLA_ALIGN(len) (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1)) 152#define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr))) 153 154#ifdef __KERNEL__ 155 156#include <linux/capability.h> 157#include <linux/skbuff.h> 158 159static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb) 160{ 161 return (struct nlmsghdr *)skb->data; 162} 163 164struct netlink_skb_parms 165{ 166 struct ucred creds; /* Skb credentials */ 167 __u32 pid; 168 __u32 dst_group; 169 kernel_cap_t eff_cap; 170 __u32 loginuid; /* Login (audit) uid */ 171 __u32 sessionid; /* Session id (audit) */ 172 __u32 sid; /* SELinux security id */ 173}; 174 175#define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb)) 176#define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds) 177 178 179extern struct sock *netlink_kernel_create(struct net *net, 180 int unit,unsigned int groups, 181 void (*input)(struct sk_buff *skb), 182 struct mutex *cb_mutex, 183 struct module *module); 184extern void netlink_kernel_release(struct sock *sk); 185extern int netlink_change_ngroups(struct sock *sk, unsigned int groups); 186extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group); 187extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err); 188extern int netlink_has_listeners(struct sock *sk, unsigned int group); 189extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock); 190extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid, 191 __u32 group, gfp_t allocation); 192extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code); 193extern int netlink_register_notifier(struct notifier_block *nb); 194extern int netlink_unregister_notifier(struct notifier_block *nb); 195 196/* finegrained unicast helpers: */ 197struct sock *netlink_getsockbyfilp(struct file *filp); 198int netlink_attachskb(struct sock *sk, struct sk_buff *skb, 199 long *timeo, struct sock *ssk); 200void netlink_detachskb(struct sock *sk, struct sk_buff *skb); 201int netlink_sendskb(struct sock *sk, struct sk_buff *skb); 202 203/* 204 * skb should fit one page. This choice is good for headerless malloc. 205 * But we should limit to 8K so that userspace does not have to 206 * use enormous buffer sizes on recvmsg() calls just to avoid 207 * MSG_TRUNC when PAGE_SIZE is very large. 208 */ 209#if PAGE_SIZE < 8192UL 210#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE) 211#else 212#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL) 213#endif 214 215#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN) 216 217 218struct netlink_callback 219{ 220 struct sk_buff *skb; 221 struct nlmsghdr *nlh; 222 int (*dump)(struct sk_buff * skb, struct netlink_callback *cb); 223 int (*done)(struct netlink_callback *cb); 224 int family; 225 long args[6]; 226}; 227 228struct netlink_notify 229{ 230 struct net *net; 231 int pid; 232 int protocol; 233}; 234 235static __inline__ struct nlmsghdr * 236__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags) 237{ 238 struct nlmsghdr *nlh; 239 int size = NLMSG_LENGTH(len); 240 241 nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size)); 242 nlh->nlmsg_type = type; 243 nlh->nlmsg_len = size; 244 nlh->nlmsg_flags = flags; 245 nlh->nlmsg_pid = pid; 246 nlh->nlmsg_seq = seq; 247 if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0) 248 memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size); 249 return nlh; 250} 251 252#define NLMSG_NEW(skb, pid, seq, type, len, flags) \ 253({ if (unlikely(skb_tailroom(skb) < (int)NLMSG_SPACE(len))) \ 254 goto nlmsg_failure; \ 255 __nlmsg_put(skb, pid, seq, type, len, flags); }) 256 257#define NLMSG_PUT(skb, pid, seq, type, len) \ 258 NLMSG_NEW(skb, pid, seq, type, len, 0) 259 260extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, 261 struct nlmsghdr *nlh, 262 int (*dump)(struct sk_buff *skb, struct netlink_callback*), 263 int (*done)(struct netlink_callback*)); 264 265 266#define NL_NONROOT_RECV 0x1 267#define NL_NONROOT_SEND 0x2 268extern void netlink_set_nonroot(int protocol, unsigned flag); 269 270#endif /* __KERNEL__ */ 271 272#endif /* __LINUX_NETLINK_H */ 273