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/rcupdate.h>
  26 #include <linux/once.h>
  27 #include <linux/fs.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 /**
  87  * enum sock_shutdown_cmd - Shutdown types
  88  * @SHUT_RD: shutdown receptions
  89  * @SHUT_WR: shutdown transmissions
  90  * @SHUT_RDWR: shutdown receptions/transmissions
  91  */
  92 enum sock_shutdown_cmd {
  93         SHUT_RD,
  94         SHUT_WR,
  95         SHUT_RDWR,
  96 };
  97
  98 struct socket_wq {
  99         /* Note: wait MUST be first field of socket_wq */
 100         wait_queue_head_t       wait;
 101         struct fasync_struct    *fasync_list;
 102         unsigned long           flags; /* %SOCKWQ_ASYNC_NOSPACE, etc */
 103         struct rcu_head         rcu;
 104 } ____cacheline_aligned_in_smp;
 105
 106 /**
 107  *  struct socket - general BSD socket
 108  *  @state: socket state (%SS_CONNECTED, etc)
 109  *  @type: socket type (%SOCK_STREAM, etc)
 110  *  @flags: socket flags (%SOCK_NOSPACE, etc)
 111  *  @ops: protocol specific socket operations
 112  *  @file: File back pointer for gc
 113  *  @sk: internal networking protocol agnostic socket representation
 114  *  @wq: wait queue for several uses
 115  */
 116 struct socket {
 117         socket_state            state;
 118
 119         short                   type;
 120
 121         unsigned long           flags;
 122
 123         struct socket_wq        *wq;
 124
 125         struct file             *file;
 126         struct sock             *sk;
 127         const struct proto_ops  *ops;
 128 };
 129
 130 struct vm_area_struct;
 131 struct page;
 132 struct sockaddr;
 133 struct msghdr;
 134 struct module;
 135 struct sk_buff;
 136 typedef int (*sk_read_actor_t)(read_descriptor_t *, struct sk_buff *,
 137                                unsigned int, size_t);
 138
 139 struct proto_ops {
 140         int             family;
 141         struct module   *owner;
 142         int             (*release)   (struct socket *sock);
 143         int             (*bind)      (struct socket *sock,
 144                                       struct sockaddr *myaddr,
 145                                       int sockaddr_len);
 146         int             (*connect)   (struct socket *sock,
 147                                       struct sockaddr *vaddr,
 148                                       int sockaddr_len, int flags);
 149         int             (*socketpair)(struct socket *sock1,
 150                                       struct socket *sock2);
 151         int             (*accept)    (struct socket *sock,
 152                                       struct socket *newsock, int flags, bool kern);
 153         int             (*getname)   (struct socket *sock,
 154                                       struct sockaddr *addr,
 155                                       int peer);
 156         __poll_t        (*poll)      (struct file *file, struct socket *sock,
 157                                       struct poll_table_struct *wait);
 158         int             (*ioctl)     (struct socket *sock, unsigned int cmd,
 159                                       unsigned long arg);
 160 #ifdef CONFIG_COMPAT
 161         int             (*compat_ioctl) (struct socket *sock, unsigned int cmd,
 162                                       unsigned long arg);
 163 #endif
 164         int             (*gettstamp) (struct socket *sock, void __user *userstamp,
 165                                       bool timeval, bool time32);
 166         int             (*listen)    (struct socket *sock, int len);
 167         int             (*shutdown)  (struct socket *sock, int flags);
 168         int             (*setsockopt)(struct socket *sock, int level,
 169                                       int optname, char __user *optval, unsigned int optlen);
 170         int             (*getsockopt)(struct socket *sock, int level,
 171                                       int optname, char __user *optval, int __user *optlen);
 172 #ifdef CONFIG_COMPAT
 173         int             (*compat_setsockopt)(struct socket *sock, int level,
 174                                       int optname, char __user *optval, unsigned int optlen);
 175         int             (*compat_getsockopt)(struct socket *sock, int level,
 176                                       int optname, char __user *optval, int __user *optlen);
 177 #endif
 178         int             (*sendmsg)   (struct socket *sock, struct msghdr *m,
 179                                       size_t total_len);
 180         /* Notes for implementing recvmsg:
 181          * ===============================
 182          * msg->msg_namelen should get updated by the recvmsg handlers
 183          * iff msg_name != NULL. It is by default 0 to prevent
 184          * returning uninitialized memory to user space.  The recvfrom
 185          * handlers can assume that msg.msg_name is either NULL or has
 186          * a minimum size of sizeof(struct sockaddr_storage).
 187          */
 188         int             (*recvmsg)   (struct socket *sock, struct msghdr *m,
 189                                       size_t total_len, int flags);
 190         int             (*mmap)      (struct file *file, struct socket *sock,
 191                                       struct vm_area_struct * vma);
 192         ssize_t         (*sendpage)  (struct socket *sock, struct page *page,
 193                                       int offset, size_t size, int flags);
 194         ssize_t         (*splice_read)(struct socket *sock,  loff_t *ppos,
 195                                        struct pipe_inode_info *pipe, size_t len, unsigned int flags);
 196         int             (*set_peek_off)(struct sock *sk, int val);
 197         int             (*peek_len)(struct socket *sock);
 198
 199         /* The following functions are called internally by kernel with
 200          * sock lock already held.
 201          */
 202         int             (*read_sock)(struct sock *sk, read_descriptor_t *desc,
 203                                      sk_read_actor_t recv_actor);
 204         int             (*sendpage_locked)(struct sock *sk, struct page *page,
 205                                            int offset, size_t size, int flags);
 206         int             (*sendmsg_locked)(struct sock *sk, struct msghdr *msg,
 207                                           size_t size);
 208         int             (*set_rcvlowat)(struct sock *sk, int val);
 209 };
 210
 211 #define DECLARE_SOCKADDR(type, dst, src)        \
 212         type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
 213
 214 struct net_proto_family {
 215         int             family;
 216         int             (*create)(struct net *net, struct socket *sock,
 217                                   int protocol, int kern);
 218         struct module   *owner;
 219 };
 220
 221 struct iovec;
 222 struct kvec;
 223
 224 enum {
 225         SOCK_WAKE_IO,
 226         SOCK_WAKE_WAITD,
 227         SOCK_WAKE_SPACE,
 228         SOCK_WAKE_URG,
 229 };
 230
 231 int sock_wake_async(struct socket_wq *sk_wq, int how, int band);
 232 int sock_register(const struct net_proto_family *fam);
 233 void sock_unregister(int family);
 234 bool sock_is_registered(int family);
 235 int __sock_create(struct net *net, int family, int type, int proto,
 236                   struct socket **res, int kern);
 237 int sock_create(int family, int type, int proto, struct socket **res);
 238 int sock_create_kern(struct net *net, int family, int type, int proto, struct socket **res);
 239 int sock_create_lite(int family, int type, int proto, struct socket **res);
 240 struct socket *sock_alloc(void);
 241 void sock_release(struct socket *sock);
 242 int sock_sendmsg(struct socket *sock, struct msghdr *msg);
 243 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags);
 244 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname);
 245 struct socket *sockfd_lookup(int fd, int *err);
 246 struct socket *sock_from_file(struct file *file, int *err);
 247 #define              sockfd_put(sock) fput(sock->file)
 248 int net_ratelimit(void);
 249
 250 #define net_ratelimited_function(function, ...)                 \
 251 do {                                                            \
 252         if (net_ratelimit())                                    \
 253                 function(__VA_ARGS__);                          \
 254 } while (0)
 255
 256 #define net_emerg_ratelimited(fmt, ...)                         \
 257         net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__)
 258 #define net_alert_ratelimited(fmt, ...)                         \
 259         net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__)
 260 #define net_crit_ratelimited(fmt, ...)                          \
 261         net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__)
 262 #define net_err_ratelimited(fmt, ...)                           \
 263         net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__)
 264 #define net_notice_ratelimited(fmt, ...)                        \
 265         net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__)
 266 #define net_warn_ratelimited(fmt, ...)                          \
 267         net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__)
 268 #define net_info_ratelimited(fmt, ...)                          \
 269         net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__)
 270 #if defined(CONFIG_DYNAMIC_DEBUG)
 271 #define net_dbg_ratelimited(fmt, ...)                                   \
 272 do {                                                                    \
 273         DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);                 \
 274         if (DYNAMIC_DEBUG_BRANCH(descriptor) &&                         \
 275             net_ratelimit())                                            \
 276                 __dynamic_pr_debug(&descriptor, pr_fmt(fmt),            \
 277                                    ##__VA_ARGS__);                      \
 278 } while (0)
 279 #elif defined(DEBUG)
 280 #define net_dbg_ratelimited(fmt, ...)                           \
 281         net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__)
 282 #else
 283 #define net_dbg_ratelimited(fmt, ...)                           \
 284         do {                                                    \
 285                 if (0)                                          \
 286                         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
 287         } while (0)
 288 #endif
 289
 290 #define net_get_random_once(buf, nbytes)                        \
 291         get_random_once((buf), (nbytes))
 292 #define net_get_random_once_wait(buf, nbytes)                   \
 293         get_random_once_wait((buf), (nbytes))
 294
 295 int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 296                    size_t num, size_t len);
 297 int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
 298                           struct kvec *vec, size_t num, size_t len);
 299 int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 300                    size_t num, size_t len, int flags);
 301
 302 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen);
 303 int kernel_listen(struct socket *sock, int backlog);
 304 int kernel_accept(struct socket *sock, struct socket **newsock, int flags);
 305 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
 306                    int flags);
 307 int kernel_getsockname(struct socket *sock, struct sockaddr *addr);
 308 int kernel_getpeername(struct socket *sock, struct sockaddr *addr);
 309 int kernel_getsockopt(struct socket *sock, int level, int optname, char *optval,
 310                       int *optlen);
 311 int kernel_setsockopt(struct socket *sock, int level, int optname, char *optval,
 312                       unsigned int optlen);
 313 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 314                     size_t size, int flags);
 315 int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
 316                            size_t size, int flags);
 317 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how);
 318
 319 /* Routine returns the IP overhead imposed by a (caller-protected) socket. */
 320 u32 kernel_sock_ip_overhead(struct sock *sk);
 321
 322 #define MODULE_ALIAS_NETPROTO(proto) \
 323         MODULE_ALIAS("net-pf-" __stringify(proto))
 324
 325 #define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
 326         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
 327
 328 #define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
 329         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 330                      "-type-" __stringify(type))
 331
 332 #define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \
 333         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 334                      name)
 335 #endif  /* _LINUX_NET_H */