include/linux/net.h

   1 /*
   2  * NET          An implementation of the SOCKET network access protocol.
   3  *              This is the master header file for the Linux NET layer,
   4  *              or, in plain English: the networking handling part of the
   5  *              kernel.
   6  *
   7  * Version:     @(#)net.h       1.0.3   05/25/93
   8  *
   9  * Authors:     Orest Zborowski, <obz@Kodak.COM>
  10  *              Ross Biro
  11  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12  *
  13  *              This program is free software; you can redistribute it and/or
  14  *              modify it under the terms of the GNU General Public License
  15  *              as published by the Free Software Foundation; either version
  16  *              2 of the License, or (at your option) any later version.
  17  */
  18 #ifndef _LINUX_NET_H
  19 #define _LINUX_NET_H
  20
  21 #include <linux/stringify.h>
  22 #include <linux/random.h>
  23 #include <linux/wait.h>
  24 #include <linux/fcntl.h>        /* For O_CLOEXEC and O_NONBLOCK */
  25 #include <linux/kmemcheck.h>
  26 #include <linux/rcupdate.h>
  27 #include <linux/once.h>
  28
  29 #include <uapi/linux/net.h>
  30
  31 struct poll_table_struct;
  32 struct pipe_inode_info;
  33 struct inode;
  34 struct file;
  35 struct net;
  36
  37 /* Historically, SOCKWQ_ASYNC_NOSPACE & SOCKWQ_ASYNC_WAITDATA were located
  38  * in sock->flags, but moved into sk->sk_wq->flags to be RCU protected.
  39  * Eventually all flags will be in sk->sk_wq_flags.
  40  */
  41 #define SOCKWQ_ASYNC_NOSPACE    0
  42 #define SOCKWQ_ASYNC_WAITDATA   1
  43 #define SOCK_NOSPACE            2
  44 #define SOCK_PASSCRED           3
  45 #define SOCK_PASSSEC            4
  46
  47 #ifndef ARCH_HAS_SOCKET_TYPES
  48 /**
  49  * enum sock_type - Socket types
  50  * @SOCK_STREAM: stream (connection) socket
  51  * @SOCK_DGRAM: datagram (conn.less) socket
  52  * @SOCK_RAW: raw socket
  53  * @SOCK_RDM: reliably-delivered message
  54  * @SOCK_SEQPACKET: sequential packet socket
  55  * @SOCK_DCCP: Datagram Congestion Control Protocol socket
  56  * @SOCK_PACKET: linux specific way of getting packets at the dev level.
  57  *                For writing rarp and other similar things on the user level.
  58  *
  59  * When adding some new socket type please
  60  * grep ARCH_HAS_SOCKET_TYPE include/asm-* /socket.h, at least MIPS
  61  * overrides this enum for binary compat reasons.
  62  */
  63 enum sock_type {
  64         SOCK_STREAM     = 1,
  65         SOCK_DGRAM      = 2,
  66         SOCK_RAW        = 3,
  67         SOCK_RDM        = 4,
  68         SOCK_SEQPACKET  = 5,
  69         SOCK_DCCP       = 6,
  70         SOCK_PACKET     = 10,
  71 };
  72
  73 #define SOCK_MAX (SOCK_PACKET + 1)
  74 /* Mask which covers at least up to SOCK_MASK-1.  The
  75  * remaining bits are used as flags. */
  76 #define SOCK_TYPE_MASK 0xf
  77
  78 /* Flags for socket, socketpair, accept4 */
  79 #define SOCK_CLOEXEC    O_CLOEXEC
  80 #ifndef SOCK_NONBLOCK
  81 #define SOCK_NONBLOCK   O_NONBLOCK
  82 #endif
  83
  84 #endif /* ARCH_HAS_SOCKET_TYPES */
  85
  86 enum sock_shutdown_cmd {
  87         SHUT_RD,
  88         SHUT_WR,
  89         SHUT_RDWR,
  90 };
  91
  92 struct socket_wq {
  93         /* Note: wait MUST be first field of socket_wq */
  94         wait_queue_head_t       wait;
  95         struct fasync_struct    *fasync_list;
  96         unsigned long           flags; /* %SOCKWQ_ASYNC_NOSPACE, etc */
  97         struct rcu_head         rcu;
  98 } ____cacheline_aligned_in_smp;
  99
 100 /**
 101  *  struct socket - general BSD socket
 102  *  @state: socket state (%SS_CONNECTED, etc)
 103  *  @type: socket type (%SOCK_STREAM, etc)
 104  *  @flags: socket flags (%SOCK_NOSPACE, etc)
 105  *  @ops: protocol specific socket operations
 106  *  @file: File back pointer for gc
 107  *  @sk: internal networking protocol agnostic socket representation
 108  *  @wq: wait queue for several uses
 109  */
 110 struct socket {
 111         socket_state            state;
 112
 113         kmemcheck_bitfield_begin(type);
 114         short                   type;
 115         kmemcheck_bitfield_end(type);
 116
 117         unsigned long           flags;
 118
 119         struct socket_wq __rcu  *wq;
 120
 121         struct file             *file;
 122         struct sock             *sk;
 123         const struct proto_ops  *ops;
 124 };
 125
 126 struct vm_area_struct;
 127 struct page;
 128 struct sockaddr;
 129 struct msghdr;
 130 struct module;
 131
 132 struct proto_ops {
 133         int             family;
 134         struct module   *owner;
 135         int             (*release)   (struct socket *sock);
 136         int             (*bind)      (struct socket *sock,
 137                                       struct sockaddr *myaddr,
 138                                       int sockaddr_len);
 139         int             (*connect)   (struct socket *sock,
 140                                       struct sockaddr *vaddr,
 141                                       int sockaddr_len, int flags);
 142         int             (*socketpair)(struct socket *sock1,
 143                                       struct socket *sock2);
 144         int             (*accept)    (struct socket *sock,
 145                                       struct socket *newsock, int flags);
 146         int             (*getname)   (struct socket *sock,
 147                                       struct sockaddr *addr,
 148                                       int *sockaddr_len, int peer);
 149         unsigned int    (*poll)      (struct file *file, struct socket *sock,
 150                                       struct poll_table_struct *wait);
 151         int             (*ioctl)     (struct socket *sock, unsigned int cmd,
 152                                       unsigned long arg);
 153 #ifdef CONFIG_COMPAT
 154         int             (*compat_ioctl) (struct socket *sock, unsigned int cmd,
 155                                       unsigned long arg);
 156 #endif
 157         int             (*listen)    (struct socket *sock, int len);
 158         int             (*shutdown)  (struct socket *sock, int flags);
 159         int             (*setsockopt)(struct socket *sock, int level,
 160                                       int optname, char __user *optval, unsigned int optlen);
 161         int             (*getsockopt)(struct socket *sock, int level,
 162                                       int optname, char __user *optval, int __user *optlen);
 163 #ifdef CONFIG_COMPAT
 164         int             (*compat_setsockopt)(struct socket *sock, int level,
 165                                       int optname, char __user *optval, unsigned int optlen);
 166         int             (*compat_getsockopt)(struct socket *sock, int level,
 167                                       int optname, char __user *optval, int __user *optlen);
 168 #endif
 169         int             (*sendmsg)   (struct socket *sock, struct msghdr *m,
 170                                       size_t total_len);
 171         /* Notes for implementing recvmsg:
 172          * ===============================
 173          * msg->msg_namelen should get updated by the recvmsg handlers
 174          * iff msg_name != NULL. It is by default 0 to prevent
 175          * returning uninitialized memory to user space.  The recvfrom
 176          * handlers can assume that msg.msg_name is either NULL or has
 177          * a minimum size of sizeof(struct sockaddr_storage).
 178          */
 179         int             (*recvmsg)   (struct socket *sock, struct msghdr *m,
 180                                       size_t total_len, int flags);
 181         int             (*mmap)      (struct file *file, struct socket *sock,
 182                                       struct vm_area_struct * vma);
 183         ssize_t         (*sendpage)  (struct socket *sock, struct page *page,
 184                                       int offset, size_t size, int flags);
 185         ssize_t         (*splice_read)(struct socket *sock,  loff_t *ppos,
 186                                        struct pipe_inode_info *pipe, size_t len, unsigned int flags);
 187         int             (*set_peek_off)(struct sock *sk, int val);
 188 };
 189
 190 #define DECLARE_SOCKADDR(type, dst, src)        \
 191         type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
 192
 193 struct net_proto_family {
 194         int             family;
 195         int             (*create)(struct net *net, struct socket *sock,
 196                                   int protocol, int kern);
 197         struct module   *owner;
 198 };
 199
 200 struct iovec;
 201 struct kvec;
 202
 203 enum {
 204         SOCK_WAKE_IO,
 205         SOCK_WAKE_WAITD,
 206         SOCK_WAKE_SPACE,
 207         SOCK_WAKE_URG,
 208 };
 209
 210 int sock_wake_async(struct socket_wq *sk_wq, int how, int band);
 211 int sock_register(const struct net_proto_family *fam);
 212 void sock_unregister(int family);
 213 int __sock_create(struct net *net, int family, int type, int proto,
 214                   struct socket **res, int kern);
 215 int sock_create(int family, int type, int proto, struct socket **res);
 216 int sock_create_kern(struct net *net, int family, int type, int proto, struct socket **res);
 217 int sock_create_lite(int family, int type, int proto, struct socket **res);
 218 struct socket *sock_alloc(void);
 219 void sock_release(struct socket *sock);
 220 int sock_sendmsg(struct socket *sock, struct msghdr *msg);
 221 int sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 222                  int flags);
 223 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname);
 224 struct socket *sockfd_lookup(int fd, int *err);
 225 struct socket *sock_from_file(struct file *file, int *err);
 226 #define              sockfd_put(sock) fput(sock->file)
 227 int net_ratelimit(void);
 228
 229 #define net_ratelimited_function(function, ...)                 \
 230 do {                                                            \
 231         if (net_ratelimit())                                    \
 232                 function(__VA_ARGS__);                          \
 233 } while (0)
 234
 235 #define net_emerg_ratelimited(fmt, ...)                         \
 236         net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__)
 237 #define net_alert_ratelimited(fmt, ...)                         \
 238         net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__)
 239 #define net_crit_ratelimited(fmt, ...)                          \
 240         net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__)
 241 #define net_err_ratelimited(fmt, ...)                           \
 242         net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__)
 243 #define net_notice_ratelimited(fmt, ...)                        \
 244         net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__)
 245 #define net_warn_ratelimited(fmt, ...)                          \
 246         net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__)
 247 #define net_info_ratelimited(fmt, ...)                          \
 248         net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__)
 249 #if defined(DEBUG)
 250 #define net_dbg_ratelimited(fmt, ...)                           \
 251         net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__)
 252 #else
 253 #define net_dbg_ratelimited(fmt, ...)                           \
 254         do {                                                    \
 255                 if (0)                                          \
 256                         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
 257         } while (0)
 258 #endif
 259
 260 #define net_get_random_once(buf, nbytes)                        \
 261         get_random_once((buf), (nbytes))
 262
 263 int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 264                    size_t num, size_t len);
 265 int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 266                    size_t num, size_t len, int flags);
 267
 268 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen);
 269 int kernel_listen(struct socket *sock, int backlog);
 270 int kernel_accept(struct socket *sock, struct socket **newsock, int flags);
 271 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
 272                    int flags);
 273 int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
 274                        int *addrlen);
 275 int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
 276                        int *addrlen);
 277 int kernel_getsockopt(struct socket *sock, int level, int optname, char *optval,
 278                       int *optlen);
 279 int kernel_setsockopt(struct socket *sock, int level, int optname, char *optval,
 280                       unsigned int optlen);
 281 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 282                     size_t size, int flags);
 283 int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
 284 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how);
 285
 286 #define MODULE_ALIAS_NETPROTO(proto) \
 287         MODULE_ALIAS("net-pf-" __stringify(proto))
 288
 289 #define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
 290         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
 291
 292 #define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
 293         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 294                      "-type-" __stringify(type))
 295
 296 #define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \
 297         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 298                      name)
 299 #endif  /* _LINUX_NET_H */