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 <uapi/linux/net.h>
  28
  29 struct poll_table_struct;
  30 struct pipe_inode_info;
  31 struct inode;
  32 struct file;
  33 struct net;
  34
  35 #define SOCK_ASYNC_NOSPACE      0
  36 #define SOCK_ASYNC_WAITDATA     1
  37 #define SOCK_NOSPACE            2
  38 #define SOCK_PASSCRED           3
  39 #define SOCK_PASSSEC            4
  40 #define SOCK_EXTERNALLY_ALLOCATED 5
  41
  42 #ifndef ARCH_HAS_SOCKET_TYPES
  43 /**
  44  * enum sock_type - Socket types
  45  * @SOCK_STREAM: stream (connection) socket
  46  * @SOCK_DGRAM: datagram (conn.less) socket
  47  * @SOCK_RAW: raw socket
  48  * @SOCK_RDM: reliably-delivered message
  49  * @SOCK_SEQPACKET: sequential packet socket
  50  * @SOCK_DCCP: Datagram Congestion Control Protocol socket
  51  * @SOCK_PACKET: linux specific way of getting packets at the dev level.
  52  *                For writing rarp and other similar things on the user level.
  53  *
  54  * When adding some new socket type please
  55  * grep ARCH_HAS_SOCKET_TYPE include/asm-* /socket.h, at least MIPS
  56  * overrides this enum for binary compat reasons.
  57  */
  58 enum sock_type {
  59         SOCK_STREAM     = 1,
  60         SOCK_DGRAM      = 2,
  61         SOCK_RAW        = 3,
  62         SOCK_RDM        = 4,
  63         SOCK_SEQPACKET  = 5,
  64         SOCK_DCCP       = 6,
  65         SOCK_PACKET     = 10,
  66 };
  67
  68 #define SOCK_MAX (SOCK_PACKET + 1)
  69 /* Mask which covers at least up to SOCK_MASK-1.  The
  70  * remaining bits are used as flags. */
  71 #define SOCK_TYPE_MASK 0xf
  72
  73 /* Flags for socket, socketpair, accept4 */
  74 #define SOCK_CLOEXEC    O_CLOEXEC
  75 #ifndef SOCK_NONBLOCK
  76 #define SOCK_NONBLOCK   O_NONBLOCK
  77 #endif
  78
  79 #endif /* ARCH_HAS_SOCKET_TYPES */
  80
  81 enum sock_shutdown_cmd {
  82         SHUT_RD         = 0,
  83         SHUT_WR         = 1,
  84         SHUT_RDWR       = 2,
  85 };
  86
  87 struct socket_wq {
  88         /* Note: wait MUST be first field of socket_wq */
  89         wait_queue_head_t       wait;
  90         struct fasync_struct    *fasync_list;
  91         struct rcu_head         rcu;
  92 } ____cacheline_aligned_in_smp;
  93
  94 /**
  95  *  struct socket - general BSD socket
  96  *  @state: socket state (%SS_CONNECTED, etc)
  97  *  @type: socket type (%SOCK_STREAM, etc)
  98  *  @flags: socket flags (%SOCK_ASYNC_NOSPACE, etc)
  99  *  @ops: protocol specific socket operations
 100  *  @file: File back pointer for gc
 101  *  @sk: internal networking protocol agnostic socket representation
 102  *  @wq: wait queue for several uses
 103  */
 104 struct socket {
 105         socket_state            state;
 106
 107         kmemcheck_bitfield_begin(type);
 108         short                   type;
 109         kmemcheck_bitfield_end(type);
 110
 111         unsigned long           flags;
 112
 113         struct socket_wq __rcu  *wq;
 114
 115         struct file             *file;
 116         struct sock             *sk;
 117         const struct proto_ops  *ops;
 118 };
 119
 120 struct vm_area_struct;
 121 struct page;
 122 struct kiocb;
 123 struct sockaddr;
 124 struct msghdr;
 125 struct module;
 126
 127 struct proto_ops {
 128         int             family;
 129         struct module   *owner;
 130         int             (*release)   (struct socket *sock);
 131         int             (*bind)      (struct socket *sock,
 132                                       struct sockaddr *myaddr,
 133                                       int sockaddr_len);
 134         int             (*connect)   (struct socket *sock,
 135                                       struct sockaddr *vaddr,
 136                                       int sockaddr_len, int flags);
 137         int             (*socketpair)(struct socket *sock1,
 138                                       struct socket *sock2);
 139         int             (*accept)    (struct socket *sock,
 140                                       struct socket *newsock, int flags);
 141         int             (*getname)   (struct socket *sock,
 142                                       struct sockaddr *addr,
 143                                       int *sockaddr_len, int peer);
 144         unsigned int    (*poll)      (struct file *file, struct socket *sock,
 145                                       struct poll_table_struct *wait);
 146         int             (*ioctl)     (struct socket *sock, unsigned int cmd,
 147                                       unsigned long arg);
 148 #ifdef CONFIG_COMPAT
 149         int             (*compat_ioctl) (struct socket *sock, unsigned int cmd,
 150                                       unsigned long arg);
 151 #endif
 152         int             (*listen)    (struct socket *sock, int len);
 153         int             (*shutdown)  (struct socket *sock, int flags);
 154         int             (*setsockopt)(struct socket *sock, int level,
 155                                       int optname, char __user *optval, unsigned int optlen);
 156         int             (*getsockopt)(struct socket *sock, int level,
 157                                       int optname, char __user *optval, int __user *optlen);
 158 #ifdef CONFIG_COMPAT
 159         int             (*compat_setsockopt)(struct socket *sock, int level,
 160                                       int optname, char __user *optval, unsigned int optlen);
 161         int             (*compat_getsockopt)(struct socket *sock, int level,
 162                                       int optname, char __user *optval, int __user *optlen);
 163 #endif
 164         int             (*sendmsg)   (struct kiocb *iocb, struct socket *sock,
 165                                       struct msghdr *m, size_t total_len);
 166         /* Notes for implementing recvmsg:
 167          * ===============================
 168          * msg->msg_namelen should get updated by the recvmsg handlers
 169          * iff msg_name != NULL. It is by default 0 to prevent
 170          * returning uninitialized memory to user space.  The recvfrom
 171          * handlers can assume that msg.msg_name is either NULL or has
 172          * a minimum size of sizeof(struct sockaddr_storage).
 173          */
 174         int             (*recvmsg)   (struct kiocb *iocb, struct socket *sock,
 175                                       struct msghdr *m, size_t total_len,
 176                                       int flags);
 177         int             (*mmap)      (struct file *file, struct socket *sock,
 178                                       struct vm_area_struct * vma);
 179         ssize_t         (*sendpage)  (struct socket *sock, struct page *page,
 180                                       int offset, size_t size, int flags);
 181         ssize_t         (*splice_read)(struct socket *sock,  loff_t *ppos,
 182                                        struct pipe_inode_info *pipe, size_t len, unsigned int flags);
 183         int             (*set_peek_off)(struct sock *sk, int val);
 184 };
 185
 186 #define DECLARE_SOCKADDR(type, dst, src)        \
 187         type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
 188
 189 struct net_proto_family {
 190         int             family;
 191         int             (*create)(struct net *net, struct socket *sock,
 192                                   int protocol, int kern);
 193         struct module   *owner;
 194 };
 195
 196 struct iovec;
 197 struct kvec;
 198
 199 enum {
 200         SOCK_WAKE_IO,
 201         SOCK_WAKE_WAITD,
 202         SOCK_WAKE_SPACE,
 203         SOCK_WAKE_URG,
 204 };
 205
 206 extern int           sock_wake_async(struct socket *sk, int how, int band);
 207 extern int           sock_register(const struct net_proto_family *fam);
 208 extern void          sock_unregister(int family);
 209 extern int           __sock_create(struct net *net, int family, int type, int proto,
 210                                  struct socket **res, int kern);
 211 extern int           sock_create(int family, int type, int proto,
 212                                  struct socket **res);
 213 extern int           sock_create_kern(int family, int type, int proto,
 214                                       struct socket **res);
 215 extern int           sock_create_lite(int family, int type, int proto,
 216                                       struct socket **res);
 217 extern void          sock_release(struct socket *sock);
 218 extern int           sock_sendmsg(struct socket *sock, struct msghdr *msg,
 219                                   size_t len);
 220 extern int           sock_recvmsg(struct socket *sock, struct msghdr *msg,
 221                                   size_t size, int flags);
 222 extern struct file  *sock_alloc_file(struct socket *sock, int flags, const char *dname);
 223 extern struct socket *sockfd_lookup(int fd, int *err);
 224 extern struct socket *sock_from_file(struct file *file, int *err);
 225 #define              sockfd_put(sock) fput(sock->file)
 226 extern int           net_ratelimit(void);
 227
 228 #define net_ratelimited_function(function, ...)                 \
 229 do {                                                            \
 230         if (net_ratelimit())                                    \
 231                 function(__VA_ARGS__);                          \
 232 } while (0)
 233
 234 #define net_emerg_ratelimited(fmt, ...)                         \
 235         net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__)
 236 #define net_alert_ratelimited(fmt, ...)                         \
 237         net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__)
 238 #define net_crit_ratelimited(fmt, ...)                          \
 239         net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__)
 240 #define net_err_ratelimited(fmt, ...)                           \
 241         net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__)
 242 #define net_notice_ratelimited(fmt, ...)                        \
 243         net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__)
 244 #define net_warn_ratelimited(fmt, ...)                          \
 245         net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__)
 246 #define net_info_ratelimited(fmt, ...)                          \
 247         net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__)
 248 #define net_dbg_ratelimited(fmt, ...)                           \
 249         net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__)
 250
 251 #define net_random()            prandom_u32()
 252 #define net_srandom(seed)       prandom_seed((__force u32)(seed))
 253
 254 extern int           kernel_sendmsg(struct socket *sock, struct msghdr *msg,
 255                                     struct kvec *vec, size_t num, size_t len);
 256 extern int           kernel_recvmsg(struct socket *sock, struct msghdr *msg,
 257                                     struct kvec *vec, size_t num,
 258                                     size_t len, int flags);
 259
 260 extern int kernel_bind(struct socket *sock, struct sockaddr *addr,
 261                        int addrlen);
 262 extern int kernel_listen(struct socket *sock, int backlog);
 263 extern int kernel_accept(struct socket *sock, struct socket **newsock,
 264                          int flags);
 265 extern int kernel_connect(struct socket *sock, struct sockaddr *addr,
 266                           int addrlen, int flags);
 267 extern int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
 268                               int *addrlen);
 269 extern int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
 270                               int *addrlen);
 271 extern int kernel_getsockopt(struct socket *sock, int level, int optname,
 272                              char *optval, int *optlen);
 273 extern int kernel_setsockopt(struct socket *sock, int level, int optname,
 274                              char *optval, unsigned int optlen);
 275 extern int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 276                            size_t size, int flags);
 277 extern int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
 278 extern int kernel_sock_shutdown(struct socket *sock,
 279                                 enum sock_shutdown_cmd how);
 280
 281 #define MODULE_ALIAS_NETPROTO(proto) \
 282         MODULE_ALIAS("net-pf-" __stringify(proto))
 283
 284 #define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
 285         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
 286
 287 #define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
 288         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 289                      "-type-" __stringify(type))
 290
 291 #define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \
 292         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 293                      name)
 294 #endif  /* _LINUX_NET_H */