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/jump_label.h>
  28 #include <uapi/linux/net.h>
  29
  30 struct poll_table_struct;
  31 struct pipe_inode_info;
  32 struct inode;
  33 struct file;
  34 struct net;
  35
  36 #define SOCK_ASYNC_NOSPACE      0
  37 #define SOCK_ASYNC_WAITDATA     1
  38 #define SOCK_NOSPACE            2
  39 #define SOCK_PASSCRED           3
  40 #define SOCK_PASSSEC            4
  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,
  83         SHUT_WR,
  84         SHUT_RDWR,
  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 sockaddr;
 123 struct msghdr;
 124 struct module;
 125
 126 struct proto_ops {
 127         int             family;
 128         struct module   *owner;
 129         int             (*release)   (struct socket *sock);
 130         int             (*bind)      (struct socket *sock,
 131                                       struct sockaddr *myaddr,
 132                                       int sockaddr_len);
 133         int             (*connect)   (struct socket *sock,
 134                                       struct sockaddr *vaddr,
 135                                       int sockaddr_len, int flags);
 136         int             (*socketpair)(struct socket *sock1,
 137                                       struct socket *sock2);
 138         int             (*accept)    (struct socket *sock,
 139                                       struct socket *newsock, int flags);
 140         int             (*getname)   (struct socket *sock,
 141                                       struct sockaddr *addr,
 142                                       int *sockaddr_len, int peer);
 143         unsigned int    (*poll)      (struct file *file, struct socket *sock,
 144                                       struct poll_table_struct *wait);
 145         int             (*ioctl)     (struct socket *sock, unsigned int cmd,
 146                                       unsigned long arg);
 147 #ifdef CONFIG_COMPAT
 148         int             (*compat_ioctl) (struct socket *sock, unsigned int cmd,
 149                                       unsigned long arg);
 150 #endif
 151         int             (*listen)    (struct socket *sock, int len);
 152         int             (*shutdown)  (struct socket *sock, int flags);
 153         int             (*setsockopt)(struct socket *sock, int level,
 154                                       int optname, char __user *optval, unsigned int optlen);
 155         int             (*getsockopt)(struct socket *sock, int level,
 156                                       int optname, char __user *optval, int __user *optlen);
 157 #ifdef CONFIG_COMPAT
 158         int             (*compat_setsockopt)(struct socket *sock, int level,
 159                                       int optname, char __user *optval, unsigned int optlen);
 160         int             (*compat_getsockopt)(struct socket *sock, int level,
 161                                       int optname, char __user *optval, int __user *optlen);
 162 #endif
 163         int             (*sendmsg)   (struct socket *sock, struct msghdr *m,
 164                                       size_t total_len);
 165         /* Notes for implementing recvmsg:
 166          * ===============================
 167          * msg->msg_namelen should get updated by the recvmsg handlers
 168          * iff msg_name != NULL. It is by default 0 to prevent
 169          * returning uninitialized memory to user space.  The recvfrom
 170          * handlers can assume that msg.msg_name is either NULL or has
 171          * a minimum size of sizeof(struct sockaddr_storage).
 172          */
 173         int             (*recvmsg)   (struct socket *sock, struct msghdr *m,
 174                                       size_t total_len, int flags);
 175         int             (*mmap)      (struct file *file, struct socket *sock,
 176                                       struct vm_area_struct * vma);
 177         ssize_t         (*sendpage)  (struct socket *sock, struct page *page,
 178                                       int offset, size_t size, int flags);
 179         ssize_t         (*splice_read)(struct socket *sock,  loff_t *ppos,
 180                                        struct pipe_inode_info *pipe, size_t len, unsigned int flags);
 181         int             (*set_peek_off)(struct sock *sk, int val);
 182 };
 183
 184 #define DECLARE_SOCKADDR(type, dst, src)        \
 185         type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
 186
 187 struct net_proto_family {
 188         int             family;
 189         int             (*create)(struct net *net, struct socket *sock,
 190                                   int protocol, int kern);
 191         struct module   *owner;
 192 };
 193
 194 struct iovec;
 195 struct kvec;
 196
 197 enum {
 198         SOCK_WAKE_IO,
 199         SOCK_WAKE_WAITD,
 200         SOCK_WAKE_SPACE,
 201         SOCK_WAKE_URG,
 202 };
 203
 204 int sock_wake_async(struct socket *sk, int how, int band);
 205 int sock_register(const struct net_proto_family *fam);
 206 void sock_unregister(int family);
 207 int __sock_create(struct net *net, int family, int type, int proto,
 208                   struct socket **res, int kern);
 209 int sock_create(int family, int type, int proto, struct socket **res);
 210 int sock_create_kern(struct net *net, int family, int type, int proto, struct socket **res);
 211 int sock_create_lite(int family, int type, int proto, struct socket **res);
 212 void sock_release(struct socket *sock);
 213 int sock_sendmsg(struct socket *sock, struct msghdr *msg);
 214 int sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 215                  int flags);
 216 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname);
 217 struct socket *sockfd_lookup(int fd, int *err);
 218 struct socket *sock_from_file(struct file *file, int *err);
 219 #define              sockfd_put(sock) fput(sock->file)
 220 int net_ratelimit(void);
 221
 222 #define net_ratelimited_function(function, ...)                 \
 223 do {                                                            \
 224         if (net_ratelimit())                                    \
 225                 function(__VA_ARGS__);                          \
 226 } while (0)
 227
 228 #define net_emerg_ratelimited(fmt, ...)                         \
 229         net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__)
 230 #define net_alert_ratelimited(fmt, ...)                         \
 231         net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__)
 232 #define net_crit_ratelimited(fmt, ...)                          \
 233         net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__)
 234 #define net_err_ratelimited(fmt, ...)                           \
 235         net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__)
 236 #define net_notice_ratelimited(fmt, ...)                        \
 237         net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__)
 238 #define net_warn_ratelimited(fmt, ...)                          \
 239         net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__)
 240 #define net_info_ratelimited(fmt, ...)                          \
 241         net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__)
 242 #define net_dbg_ratelimited(fmt, ...)                           \
 243         net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__)
 244
 245 bool __net_get_random_once(void *buf, int nbytes, bool *done,
 246                            struct static_key *done_key);
 247
 248 #define net_get_random_once(buf, nbytes)                                \
 249         ({                                                              \
 250                 bool ___ret = false;                                    \
 251                 static bool ___done = false;                            \
 252                 static struct static_key ___once_key =                  \
 253                         STATIC_KEY_INIT_TRUE;                           \
 254                 if (static_key_true(&___once_key))                      \
 255                         ___ret = __net_get_random_once(buf,             \
 256                                                        nbytes,          \
 257                                                        &___done,        \
 258                                                        &___once_key);   \
 259                 ___ret;                                                 \
 260         })
 261
 262 int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 263                    size_t num, size_t len);
 264 int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
 265                    size_t num, size_t len, int flags);
 266
 267 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen);
 268 int kernel_listen(struct socket *sock, int backlog);
 269 int kernel_accept(struct socket *sock, struct socket **newsock, int flags);
 270 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
 271                    int flags);
 272 int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
 273                        int *addrlen);
 274 int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
 275                        int *addrlen);
 276 int kernel_getsockopt(struct socket *sock, int level, int optname, char *optval,
 277                       int *optlen);
 278 int kernel_setsockopt(struct socket *sock, int level, int optname, char *optval,
 279                       unsigned int optlen);
 280 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 281                     size_t size, int flags);
 282 int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
 283 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how);
 284
 285 #define MODULE_ALIAS_NETPROTO(proto) \
 286         MODULE_ALIAS("net-pf-" __stringify(proto))
 287
 288 #define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
 289         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
 290
 291 #define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
 292         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 293                      "-type-" __stringify(type))
 294
 295 #define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \
 296         MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
 297                      name)
 298 #endif  /* _LINUX_NET_H */