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 #include <linux/fs.h>
  29
  30 #include <uapi/linux/net.h>
  31
  32 struct poll_table_struct;
  33 struct pipe_inode_info;
  34 struct inode;
  35 struct file;
  36 struct net;
  37
  38 /* Historically, SOCKWQ_ASYNC_NOSPACE & SOCKWQ_ASYNC_WAITDATA were located
  39  * in sock->flags, but moved into sk->sk_wq->flags to be RCU protected.
  40  * Eventually all flags will be in sk->sk_wq_flags.
  41  */
  42 #define SOCKWQ_ASYNC_NOSPACE    0
  43 #define SOCKWQ_ASYNC_WAITDATA   1
  44 #define SOCK_NOSPACE            2
  45 #define SOCK_PASSCRED           3
  46 #define SOCK_PASSSEC            4
  47
  48 #ifndef ARCH_HAS_SOCKET_TYPES
  49 /**
  50  * enum sock_type - Socket types
  51  * @SOCK_STREAM: stream (connection) socket
  52  * @SOCK_DGRAM: datagram (conn.less) socket
  53  * @SOCK_RAW: raw socket
  54  * @SOCK_RDM: reliably-delivered message
  55  * @SOCK_SEQPACKET: sequential packet socket
  56  * @SOCK_DCCP: Datagram Congestion Control Protocol socket
  57  * @SOCK_PACKET: linux specific way of getting packets at the dev level.
  58  *                For writing rarp and other similar things on the user level.
  59  *
  60  * When adding some new socket type please
  61  * grep ARCH_HAS_SOCKET_TYPE include/asm-* /socket.h, at least MIPS
  62  * overrides this enum for binary compat reasons.
  63  */
  64 enum sock_type {
  65         SOCK_STREAM     = 1,
  66         SOCK_DGRAM      = 2,
  67         SOCK_RAW        = 3,
  68         SOCK_RDM        = 4,
  69         SOCK_SEQPACKET  = 5,
  70         SOCK_DCCP       = 6,
  71         SOCK_PACKET     = 10,
  72 };
  73
  74 #define SOCK_MAX (SOCK_PACKET + 1)
  75 /* Mask which covers at least up to SOCK_MASK-1.  The
  76  * remaining bits are used as flags. */
  77 #define SOCK_TYPE_MASK 0xf
  78
  79 /* Flags for socket, socketpair, accept4 */
  80 #define SOCK_CLOEXEC    O_CLOEXEC
  81 #ifndef SOCK_NONBLOCK
  82 #define SOCK_NONBLOCK   O_NONBLOCK
  83 #endif
  84
  85 #endif /* ARCH_HAS_SOCKET_TYPES */
  86
  87 enum sock_shutdown_cmd {
  88         SHUT_RD,
  89         SHUT_WR,
  90         SHUT_RDWR,
  91 };
  92
  93 struct socket_wq {
  94         /* Note: wait MUST be first field of socket_wq */
  95         wait_queue_head_t       wait;
  96         struct fasync_struct    *fasync_list;
  97         unsigned long           flags; /* %SOCKWQ_ASYNC_NOSPACE, etc */
  98         struct rcu_head         rcu;
  99 } ____cacheline_aligned_in_smp;
 100
 101 /**
 102  *  struct socket - general BSD socket
 103  *  @state: socket state (%SS_CONNECTED, etc)
 104  *  @type: socket type (%SOCK_STREAM, etc)
 105  *  @flags: socket flags (%SOCK_NOSPACE, etc)
 106  *  @ops: protocol specific socket operations
 107  *  @file: File back pointer for gc
 108  *  @sk: internal networking protocol agnostic socket representation
 109  *  @wq: wait queue for several uses
 110  */
 111 struct socket {
 112         socket_state            state;
 113
 114         kmemcheck_bitfield_begin(type);
 115         short                   type;
 116         kmemcheck_bitfield_end(type);
 117
 118         unsigned long           flags;
 119
 120         struct socket_wq __rcu  *wq;
 121
 122         struct file             *file;
 123         struct sock             *sk;
 124         const struct proto_ops  *ops;
 125 };
 126
 127 struct vm_area_struct;
 128 struct page;
 129 struct sockaddr;
 130 struct msghdr;
 131 struct module;
 132 struct sk_buff;
 133 typedef int (*sk_read_actor_t)(read_descriptor_t *, struct sk_buff *,
 134                                unsigned int, size_t);
 135
 136 struct proto_ops {
 137         int             family;
 138         struct module   *owner;
 139         int             (*release)   (struct socket *sock);
 140         int             (*bind)      (struct socket *sock,
 141                                       struct sockaddr *myaddr,
 142                                       int sockaddr_len);
 143         int             (*connect)   (struct socket *sock,
 144                                       struct sockaddr *vaddr,
 145                                       int sockaddr_len, int flags);
 146         int             (*socketpair)(struct socket *sock1,
 147                                       struct socket *sock2);
 148         int             (*accept)    (struct socket *sock,
 149                                       struct socket *newsock, int flags, bool kern);
 150         int             (*getname)   (struct socket *sock,
 151                                       struct sockaddr *addr,
 152                                       int *sockaddr_len, int peer);
 153         unsigned int    (*poll)      (struct file *file, struct socket *sock,
 154                                       struct poll_table_struct *wait);
 155         int             (*ioctl)     (struct socket *sock, unsigned int cmd,
 156                                       unsigned long arg);
 157 #ifdef CONFIG_COMPAT
 158         int             (*compat_ioctl) (struct socket *sock, unsigned int cmd,
 159                                       unsigned long arg);
 160 #endif
 161         int             (*listen)    (struct socket *sock, int len);
 162         int             (*shutdown)  (struct socket *sock, int flags);
 163         int             (*setsockopt)(struct socket *sock, int level,
 164                                       int optname, char __user *optval, unsigned int optlen);
 165         int             (*getsockopt)(struct socket *sock, int level,
 166                                       int optname, char __user *optval, int __user *optlen);
 167 #ifdef CONFIG_COMPAT
 168         int             (*compat_setsockopt)(struct socket *sock, int level,
 169                                       int optname, char __user *optval, unsigned int optlen);
 170         int             (*compat_getsockopt)(struct socket *sock, int level,
 171                                       int optname, char __user *optval, int __user *optlen);
 172 #endif
 173         int             (*sendmsg)   (struct socket *sock, struct msghdr *m,
 174                                       size_t total_len);
 175         /* Notes for implementing recvmsg:
 176          * ===============================
 177          * msg->msg_namelen should get updated by the recvmsg handlers
 178          * iff msg_name != NULL. It is by default 0 to prevent
 179          * returning uninitialized memory to user space.  The recvfrom
 180          * handlers can assume that msg.msg_name is either NULL or has
 181          * a minimum size of sizeof(struct sockaddr_storage).
 182          */
 183         int             (*recvmsg)   (struct socket *sock, struct msghdr *m,
 184                                       size_t total_len, int flags);
 185         int             (*mmap)      (struct file *file, struct socket *sock,
 186                                       struct vm_area_struct * vma);
 187         ssize_t         (*sendpage)  (struct socket *sock, struct page *page,
 188                                       int offset, size_t size, int flags);
 189         ssize_t         (*splice_read)(struct socket *sock,  loff_t *ppos,
 190                                        struct pipe_inode_info *pipe, size_t len, unsigned int flags);
 191         int             (*set_peek_off)(struct sock *sk, int val);
 192         int             (*peek_len)(struct socket *sock);
 193         int             (*read_sock)(struct sock *sk, read_descriptor_t *desc,
 194                                      sk_read_actor_t recv_actor);
 195 };
 196
 197 #define DECLARE_SOCKADDR(type, dst, src)        \
 198         type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
 199
 200 struct net_proto_family {
 201         int             family;
 202         int             (*create)(struct net *net, struct socket *sock,
 203                                   int protocol, int kern);
 204         struct module   *owner;
 205 };
 206
 207 struct iovec;
 208 struct kvec;
 209
 210 enum {
 211         SOCK_WAKE_IO,
 212         SOCK_WAKE_WAITD,
 213         SOCK_WAKE_SPACE,
 214         SOCK_WAKE_URG,
 215 };
 216
 217 int sock_wake_async(struct socket_wq *sk_wq, int how, int band);
 218 int sock_register(const struct net_proto_family *fam);
 219 void sock_unregister(int family);
 220 int __sock_create(struct net *net, int family, int type, int proto,
 221                   struct socket **res, int kern);
 222 int sock_create(int family, int type, int proto, struct socket **res);
 223 int sock_create_kern(struct net *net, int family, int type, int proto, struct socket **res);
 224 int sock_create_lite(int family, int type, int proto, struct socket **res);
 225 struct socket *sock_alloc(void);
 226 void sock_release(struct socket *sock);
 227 int sock_sendmsg(struct socket *sock, struct msghdr *msg);
 228 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags);
 229 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname);
 230 struct socket *sockfd_lookup(int fd, int *err);
 231 struct socket *sock_from_file(struct file *file, int *err);
 232 #define              sockfd_put(sock) fput(sock->file)
 233 int net_ratelimit(void);
 234
 235 #define net_ratelimited_function(function, ...)                 \
 236 do {                                                            \
 237         if (net_ratelimit())                                    \
 238                 function(__VA_ARGS__);                          \
 239 } while (0)
 240
 241 #define net_emerg_ratelimited(fmt, ...)                         \
 242         net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__)
 243 #define net_alert_ratelimited(fmt, ...)                         \
 244         net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__)
 245 #define net_crit_ratelimited(fmt, ...)                          \
 246         net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__)
 247 #define net_err_ratelimited(fmt, ...)                           \
 248         net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__)
 249 #define net_notice_ratelimited(fmt, ...)                        \
 250         net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__)
 251 #define net_warn_ratelimited(fmt, ...)                          \
 252         net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__)
 253 #define net_info_ratelimited(fmt, ...)                          \
 254         net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__)
 255 #if defined(CONFIG_DYNAMIC_DEBUG)
 256 #define net_dbg_ratelimited(fmt, ...)                                   \
 257 do {                                                                    \
 258         DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);                 \
 259         if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&        \
 260             net_ratelimit())                                            \
 261                 __dynamic_pr_debug(&descriptor, pr_fmt(fmt),            \
 262                                    ##__VA_ARGS__);                      \
 263 } while (0)
 264 #elif defined(DEBUG)
 265 #define net_dbg_ratelimited(fmt, ...)                           \
 266         net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__)
 267 #else
 268 #define net_dbg_ratelimited(fmt, ...)                           \
 269         do {                                                    \
 270                 if (0)                                          \
 271                         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
 272         } while (0)
 273 #endif
 274
 275 #define net_get_random_once(buf, nbytes)                        \
 276         get_random_once((buf), (nbytes))
 277 #define net_get_random_once_wait(buf, nbytes)                   \
 278         get_random_once_wait((buf), (nbytes))
 279
 280 int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 281                    size_t num, size_t len);
 282 int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 283                    size_t num, size_t len, int flags);
 284
 285 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen);
 286 int kernel_listen(struct socket *sock, int backlog);
 287 int kernel_accept(struct socket *sock, struct socket **newsock, int flags);
 288 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
 289                    int flags);
 290 int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
 291                        int *addrlen);
 292 int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
 293                        int *addrlen);
 294 int kernel_getsockopt(struct socket *sock, int level, int optname, char *optval,
 295                       int *optlen);
 296 int kernel_setsockopt(struct socket *sock, int level, int optname, char *optval,
 297                       unsigned int optlen);
 298 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 299                     size_t size, int flags);
 300 int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
 301 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how);
 302
 303 /* Routine returns the IP overhead imposed by a (caller-protected) socket. */
 304 u32 kernel_sock_ip_overhead(struct sock *sk);
 305
 306 #define MODULE_ALIAS_NETPROTO(proto) \
 307         MODULE_ALIAS("net-pf-" __stringify(proto))
 308
 309 #define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
 310         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
 311
 312 #define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
 313         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 314                      "-type-" __stringify(type))
 315
 316 #define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \
 317         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 318                      name)
 319 #endif  /* _LINUX_NET_H */