1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * NET An implementation of the SOCKET network access protocol. 4 * This is the master header file for the Linux NET layer, 5 * or, in plain English: the networking handling part of the 6 * kernel. 7 * 8 * Version: @(#)net.h 1.0.3 05/25/93 9 * 10 * Authors: Orest Zborowski, <[email protected]> 11 * Ross Biro 12 * Fred N. van Kempen, <[email protected]> 13 */ 14 #ifndef _LINUX_NET_H 15 #define _LINUX_NET_H 16 17 #include <linux/stringify.h> 18 #include <linux/random.h> 19 #include <linux/wait.h> 20 #include <linux/fcntl.h> /* For O_CLOEXEC and O_NONBLOCK */ 21 #include <linux/rcupdate.h> 22 #include <linux/once.h> 23 #include <linux/fs.h> 24 #include <linux/mm.h> 25 #include <linux/sockptr.h> 26 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 /* Historically, SOCKWQ_ASYNC_NOSPACE & SOCKWQ_ASYNC_WAITDATA were located 36 * in sock->flags, but moved into sk->sk_wq->flags to be RCU protected. 37 * Eventually all flags will be in sk->sk_wq->flags. 38 */ 39 #define SOCKWQ_ASYNC_NOSPACE 0 40 #define SOCKWQ_ASYNC_WAITDATA 1 41 #define SOCK_NOSPACE 2 42 #define SOCK_PASSCRED 3 43 #define SOCK_PASSSEC 4 44 45 #define PROTO_CMSG_DATA_ONLY 0x0001 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 file *file; 124 struct sock *sk; 125 const struct proto_ops *ops; 126 127 struct socket_wq wq; 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 unsigned int flags; 142 struct module *owner; 143 int (*release) (struct socket *sock); 144 int (*bind) (struct socket *sock, 145 struct sockaddr *myaddr, 146 int sockaddr_len); 147 int (*connect) (struct socket *sock, 148 struct sockaddr *vaddr, 149 int sockaddr_len, int flags); 150 int (*socketpair)(struct socket *sock1, 151 struct socket *sock2); 152 int (*accept) (struct socket *sock, 153 struct socket *newsock, int flags, bool kern); 154 int (*getname) (struct socket *sock, 155 struct sockaddr *addr, 156 int peer); 157 __poll_t (*poll) (struct file *file, struct socket *sock, 158 struct poll_table_struct *wait); 159 int (*ioctl) (struct socket *sock, unsigned int cmd, 160 unsigned long arg); 161 #ifdef CONFIG_COMPAT 162 int (*compat_ioctl) (struct socket *sock, unsigned int cmd, 163 unsigned long arg); 164 #endif 165 int (*gettstamp) (struct socket *sock, void __user *userstamp, 166 bool timeval, bool time32); 167 int (*listen) (struct socket *sock, int len); 168 int (*shutdown) (struct socket *sock, int flags); 169 int (*setsockopt)(struct socket *sock, int level, 170 int optname, sockptr_t optval, 171 unsigned int optlen); 172 int (*getsockopt)(struct socket *sock, int level, 173 int optname, char __user *optval, int __user *optlen); 174 void (*show_fdinfo)(struct seq_file *m, struct socket *sock); 175 int (*sendmsg) (struct socket *sock, struct msghdr *m, 176 size_t total_len); 177 /* Notes for implementing recvmsg: 178 * =============================== 179 * msg->msg_namelen should get updated by the recvmsg handlers 180 * iff msg_name != NULL. It is by default 0 to prevent 181 * returning uninitialized memory to user space. The recvfrom 182 * handlers can assume that msg.msg_name is either NULL or has 183 * a minimum size of sizeof(struct sockaddr_storage). 184 */ 185 int (*recvmsg) (struct socket *sock, struct msghdr *m, 186 size_t total_len, int flags); 187 int (*mmap) (struct file *file, struct socket *sock, 188 struct vm_area_struct * vma); 189 ssize_t (*sendpage) (struct socket *sock, struct page *page, 190 int offset, size_t size, int flags); 191 ssize_t (*splice_read)(struct socket *sock, loff_t *ppos, 192 struct pipe_inode_info *pipe, size_t len, unsigned int flags); 193 int (*set_peek_off)(struct sock *sk, int val); 194 int (*peek_len)(struct socket *sock); 195 196 /* The following functions are called internally by kernel with 197 * sock lock already held. 198 */ 199 int (*read_sock)(struct sock *sk, read_descriptor_t *desc, 200 sk_read_actor_t recv_actor); 201 int (*sendpage_locked)(struct sock *sk, struct page *page, 202 int offset, size_t size, int flags); 203 int (*sendmsg_locked)(struct sock *sk, struct msghdr *msg, 204 size_t size); 205 int (*set_rcvlowat)(struct sock *sk, int val); 206 }; 207 208 #define DECLARE_SOCKADDR(type, dst, src) \ 209 type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; }) 210 211 struct net_proto_family { 212 int family; 213 int (*create)(struct net *net, struct socket *sock, 214 int protocol, int kern); 215 struct module *owner; 216 }; 217 218 struct iovec; 219 struct kvec; 220 221 enum { 222 SOCK_WAKE_IO, 223 SOCK_WAKE_WAITD, 224 SOCK_WAKE_SPACE, 225 SOCK_WAKE_URG, 226 }; 227 228 int sock_wake_async(struct socket_wq *sk_wq, int how, int band); 229 int sock_register(const struct net_proto_family *fam); 230 void sock_unregister(int family); 231 bool sock_is_registered(int family); 232 int __sock_create(struct net *net, int family, int type, int proto, 233 struct socket **res, int kern); 234 int sock_create(int family, int type, int proto, struct socket **res); 235 int sock_create_kern(struct net *net, int family, int type, int proto, struct socket **res); 236 int sock_create_lite(int family, int type, int proto, struct socket **res); 237 struct socket *sock_alloc(void); 238 void sock_release(struct socket *sock); 239 int sock_sendmsg(struct socket *sock, struct msghdr *msg); 240 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags); 241 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname); 242 struct socket *sockfd_lookup(int fd, int *err); 243 struct socket *sock_from_file(struct file *file, int *err); 244 #define sockfd_put(sock) fput(sock->file) 245 int net_ratelimit(void); 246 247 #define net_ratelimited_function(function, ...) \ 248 do { \ 249 if (net_ratelimit()) \ 250 function(__VA_ARGS__); \ 251 } while (0) 252 253 #define net_emerg_ratelimited(fmt, ...) \ 254 net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__) 255 #define net_alert_ratelimited(fmt, ...) \ 256 net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__) 257 #define net_crit_ratelimited(fmt, ...) \ 258 net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__) 259 #define net_err_ratelimited(fmt, ...) \ 260 net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__) 261 #define net_notice_ratelimited(fmt, ...) \ 262 net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__) 263 #define net_warn_ratelimited(fmt, ...) \ 264 net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__) 265 #define net_info_ratelimited(fmt, ...) \ 266 net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__) 267 #if defined(CONFIG_DYNAMIC_DEBUG) || \ 268 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) 269 #define net_dbg_ratelimited(fmt, ...) \ 270 do { \ 271 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \ 272 if (DYNAMIC_DEBUG_BRANCH(descriptor) && \ 273 net_ratelimit()) \ 274 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), \ 275 ##__VA_ARGS__); \ 276 } while (0) 277 #elif defined(DEBUG) 278 #define net_dbg_ratelimited(fmt, ...) \ 279 net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__) 280 #else 281 #define net_dbg_ratelimited(fmt, ...) \ 282 do { \ 283 if (0) \ 284 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \ 285 } while (0) 286 #endif 287 288 #define net_get_random_once(buf, nbytes) \ 289 get_random_once((buf), (nbytes)) 290 #define net_get_random_once_wait(buf, nbytes) \ 291 get_random_once_wait((buf), (nbytes)) 292 293 /* 294 * E.g. XFS meta- & log-data is in slab pages, or bcache meta 295 * data pages, or other high order pages allocated by 296 * __get_free_pages() without __GFP_COMP, which have a page_count 297 * of 0 and/or have PageSlab() set. We cannot use send_page for 298 * those, as that does get_page(); put_page(); and would cause 299 * either a VM_BUG directly, or __page_cache_release a page that 300 * would actually still be referenced by someone, leading to some 301 * obscure delayed Oops somewhere else. 302 */ 303 static inline bool sendpage_ok(struct page *page) 304 { 305 return !PageSlab(page) && page_count(page) >= 1; 306 } 307 308 int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec, 309 size_t num, size_t len); 310 int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg, 311 struct kvec *vec, size_t num, size_t len); 312 int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec, 313 size_t num, size_t len, int flags); 314 315 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen); 316 int kernel_listen(struct socket *sock, int backlog); 317 int kernel_accept(struct socket *sock, struct socket **newsock, int flags); 318 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen, 319 int flags); 320 int kernel_getsockname(struct socket *sock, struct sockaddr *addr); 321 int kernel_getpeername(struct socket *sock, struct sockaddr *addr); 322 int kernel_sendpage(struct socket *sock, struct page *page, int offset, 323 size_t size, int flags); 324 int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset, 325 size_t size, int flags); 326 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how); 327 328 /* Routine returns the IP overhead imposed by a (caller-protected) socket. */ 329 u32 kernel_sock_ip_overhead(struct sock *sk); 330 331 #define MODULE_ALIAS_NETPROTO(proto) \ 332 MODULE_ALIAS("net-pf-" __stringify(proto)) 333 334 #define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \ 335 MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto)) 336 337 #define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \ 338 MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \ 339 "-type-" __stringify(type)) 340 341 #define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \ 342 MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \ 343 name) 344 #endif /* _LINUX_NET_H */ 345