1/*-
2 * Copyright (c) 1982, 1986, 1990, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	@(#)socketvar.h	8.3 (Berkeley) 2/19/95
30 *
31 * $FreeBSD$
32 */
33
34#ifndef _SYS_SOCKETVAR_H_
35#define _SYS_SOCKETVAR_H_
36
37#include <sys/queue.h>			/* for TAILQ macros */
38#include <sys/selinfo.h>		/* for struct selinfo */
39#include <sys/_lock.h>
40#include <sys/_mutex.h>
41#include <sys/_sx.h>
42#include <sys/sockbuf.h>
43#include <sys/sockstate.h>
44#ifdef _KERNEL
45#include <sys/sockopt.h>
46#endif
47
48struct vnet;
49
50/*
51 * Kernel structure per socket.
52 * Contains send and receive buffer queues,
53 * handle on protocol and pointer to protocol
54 * private data and error information.
55 */
56typedef	u_quad_t so_gen_t;
57
58struct socket;
59
60/*-
61 * Locking key to struct socket:
62 * (a) constant after allocation, no locking required.
63 * (b) locked by SOCK_LOCK(so).
64 * (c) locked by SOCKBUF_LOCK(&so->so_rcv).
65 * (d) locked by SOCKBUF_LOCK(&so->so_snd).
66 * (e) locked by ACCEPT_LOCK().
67 * (f) not locked since integer reads/writes are atomic.
68 * (g) used only as a sleep/wakeup address, no value.
69 * (h) locked by global mutex so_global_mtx.
70 */
71struct socket {
72	int	so_count;		/* (b) reference count */
73	short	so_type;		/* (a) generic type, see socket.h */
74	short	so_options;		/* from socket call, see socket.h */
75	short	so_linger;		/* time to linger while closing */
76	short	so_state;		/* (b) internal state flags SS_* */
77	int	so_qstate;		/* (e) internal state flags SQ_* */
78	void	*so_pcb;		/* protocol control block */
79	struct	vnet *so_vnet;		/* network stack instance */
80	struct	protosw *so_proto;	/* (a) protocol handle */
81/*
82 * Variables for connection queuing.
83 * Socket where accepts occur is so_head in all subsidiary sockets.
84 * If so_head is 0, socket is not related to an accept.
85 * For head socket so_incomp queues partially completed connections,
86 * while so_comp is a queue of connections ready to be accepted.
87 * If a connection is aborted and it has so_head set, then
88 * it has to be pulled out of either so_incomp or so_comp.
89 * We allow connections to queue up based on current queue lengths
90 * and limit on number of queued connections for this socket.
91 */
92	struct	socket *so_head;	/* (e) back pointer to listen socket */
93	TAILQ_HEAD(, socket) so_incomp;	/* (e) queue of partial unaccepted connections */
94	TAILQ_HEAD(, socket) so_comp;	/* (e) queue of complete unaccepted connections */
95	TAILQ_ENTRY(socket) so_list;	/* (e) list of unaccepted connections */
96	u_short	so_qlen;		/* (e) number of unaccepted connections */
97	u_short	so_incqlen;		/* (e) number of unaccepted incomplete
98					   connections */
99	u_short	so_qlimit;		/* (e) max number queued connections */
100	short	so_timeo;		/* (g) connection timeout */
101	u_short	so_error;		/* (f) error affecting connection */
102	struct	sigio *so_sigio;	/* [sg] information for async I/O or
103					   out of band data (SIGURG) */
104	u_long	so_oobmark;		/* (c) chars to oob mark */
105	TAILQ_HEAD(, aiocblist) so_aiojobq; /* AIO ops waiting on socket */
106
107	struct sockbuf so_rcv, so_snd;
108
109	struct	ucred *so_cred;		/* (a) user credentials */
110	struct	label *so_label;	/* (b) MAC label for socket */
111	struct	label *so_peerlabel;	/* (b) cached MAC label for peer */
112	/* NB: generation count must not be first. */
113	so_gen_t so_gencnt;		/* (h) generation count */
114	void	*so_emuldata;		/* (b) private data for emulators */
115 	struct so_accf {
116		struct	accept_filter *so_accept_filter;
117		void	*so_accept_filter_arg;	/* saved filter args */
118		char	*so_accept_filter_str;	/* saved user args */
119	} *so_accf;
120	/*
121	 * so_fibnum, so_user_cookie and friends can be used to attach
122	 * some user-specified metadata to a socket, which then can be
123	 * used by the kernel for various actions.
124	 * so_user_cookie is used by ipfw/dummynet.
125	 */
126	int so_fibnum;		/* routing domain for this socket */
127	uint32_t so_user_cookie;
128};
129
130/*
131 * Global accept mutex to serialize access to accept queues and
132 * fields associated with multiple sockets.  This allows us to
133 * avoid defining a lock order between listen and accept sockets
134 * until such time as it proves to be a good idea.
135 */
136extern struct mtx accept_mtx;
137#define	ACCEPT_LOCK_ASSERT()		mtx_assert(&accept_mtx, MA_OWNED)
138#define	ACCEPT_UNLOCK_ASSERT()		mtx_assert(&accept_mtx, MA_NOTOWNED)
139#define	ACCEPT_LOCK()			mtx_lock(&accept_mtx)
140#define	ACCEPT_UNLOCK()			mtx_unlock(&accept_mtx)
141
142/*
143 * Per-socket mutex: we reuse the receive socket buffer mutex for space
144 * efficiency.  This decision should probably be revisited as we optimize
145 * locking for the socket code.
146 */
147#define	SOCK_MTX(_so)			SOCKBUF_MTX(&(_so)->so_rcv)
148#define	SOCK_LOCK(_so)			SOCKBUF_LOCK(&(_so)->so_rcv)
149#define	SOCK_OWNED(_so)			SOCKBUF_OWNED(&(_so)->so_rcv)
150#define	SOCK_UNLOCK(_so)		SOCKBUF_UNLOCK(&(_so)->so_rcv)
151#define	SOCK_LOCK_ASSERT(_so)		SOCKBUF_LOCK_ASSERT(&(_so)->so_rcv)
152
153/*
154 * Socket state bits stored in so_qstate.
155 */
156#define	SQ_INCOMP		0x0800	/* unaccepted, incomplete connection */
157#define	SQ_COMP			0x1000	/* unaccepted, complete connection */
158
159/*
160 * Externalized form of struct socket used by the sysctl(3) interface.
161 */
162struct xsocket {
163	size_t	xso_len;	/* length of this structure */
164	struct	socket *xso_so;	/* makes a convenient handle sometimes */
165	short	so_type;
166	short	so_options;
167	short	so_linger;
168	short	so_state;
169	caddr_t	so_pcb;		/* another convenient handle */
170	int	xso_protocol;
171	int	xso_family;
172	u_short	so_qlen;
173	u_short	so_incqlen;
174	u_short	so_qlimit;
175	short	so_timeo;
176	u_short	so_error;
177	pid_t	so_pgid;
178	u_long	so_oobmark;
179	struct xsockbuf so_rcv, so_snd;
180	uid_t	so_uid;		/* XXX */
181};
182
183#ifdef _KERNEL
184
185/*
186 * Macros for sockets and socket buffering.
187 */
188
189/*
190 * Flags to sblock().
191 */
192#define	SBL_WAIT	0x00000001	/* Wait if not immediately available. */
193#define	SBL_NOINTR	0x00000002	/* Force non-interruptible sleep. */
194#define	SBL_VALID	(SBL_WAIT | SBL_NOINTR)
195
196/*
197 * Do we need to notify the other side when I/O is possible?
198 */
199#define	sb_notify(sb)	(((sb)->sb_flags & (SB_WAIT | SB_SEL | SB_ASYNC | \
200    SB_UPCALL | SB_AIO | SB_KNOTE)) != 0)
201
202/* do we have to send all at once on a socket? */
203#define	sosendallatonce(so) \
204    ((so)->so_proto->pr_flags & PR_ATOMIC)
205
206/* can we read something from so? */
207#define	soreadabledata(so) \
208    ((so)->so_rcv.sb_cc >= (so)->so_rcv.sb_lowat || \
209	!TAILQ_EMPTY(&(so)->so_comp) || (so)->so_error)
210#define	soreadable(so) \
211	(soreadabledata(so) || ((so)->so_rcv.sb_state & SBS_CANTRCVMORE))
212
213/* can we write something to so? */
214#define	sowriteable(so) \
215    ((sbspace(&(so)->so_snd) >= (so)->so_snd.sb_lowat && \
216	(((so)->so_state&SS_ISCONNECTED) || \
217	  ((so)->so_proto->pr_flags&PR_CONNREQUIRED)==0)) || \
218     ((so)->so_snd.sb_state & SBS_CANTSENDMORE) || \
219     (so)->so_error)
220
221/*
222 * soref()/sorele() ref-count the socket structure.  Note that you must
223 * still explicitly close the socket, but the last ref count will free
224 * the structure.
225 */
226#define	soref(so) do {							\
227	SOCK_LOCK_ASSERT(so);						\
228	++(so)->so_count;						\
229} while (0)
230
231#define	sorele(so) do {							\
232	ACCEPT_LOCK_ASSERT();						\
233	SOCK_LOCK_ASSERT(so);						\
234	if ((so)->so_count <= 0)					\
235		panic("sorele");					\
236	if (--(so)->so_count == 0)					\
237		sofree(so);						\
238	else {								\
239		SOCK_UNLOCK(so);					\
240		ACCEPT_UNLOCK();					\
241	}								\
242} while (0)
243
244/*
245 * In sorwakeup() and sowwakeup(), acquire the socket buffer lock to
246 * avoid a non-atomic test-and-wakeup.  However, sowakeup is
247 * responsible for releasing the lock if it is called.  We unlock only
248 * if we don't call into sowakeup.  If any code is introduced that
249 * directly invokes the underlying sowakeup() primitives, it must
250 * maintain the same semantics.
251 */
252#define	sorwakeup_locked(so) do {					\
253	SOCKBUF_LOCK_ASSERT(&(so)->so_rcv);				\
254	if (sb_notify(&(so)->so_rcv))					\
255		sowakeup((so), &(so)->so_rcv);	 			\
256	else								\
257		SOCKBUF_UNLOCK(&(so)->so_rcv);				\
258} while (0)
259
260#define	sorwakeup(so) do {						\
261	SOCKBUF_LOCK(&(so)->so_rcv);					\
262	sorwakeup_locked(so);						\
263} while (0)
264
265#define	sowwakeup_locked(so) do {					\
266	SOCKBUF_LOCK_ASSERT(&(so)->so_snd);				\
267	if (sb_notify(&(so)->so_snd))					\
268		sowakeup((so), &(so)->so_snd); 				\
269	else								\
270		SOCKBUF_UNLOCK(&(so)->so_snd);				\
271} while (0)
272
273#define	sowwakeup(so) do {						\
274	SOCKBUF_LOCK(&(so)->so_snd);					\
275	sowwakeup_locked(so);						\
276} while (0)
277
278struct accept_filter {
279	char	accf_name[16];
280	int	(*accf_callback)
281		(struct socket *so, void *arg, int waitflag);
282	void *	(*accf_create)
283		(struct socket *so, char *arg);
284	void	(*accf_destroy)
285		(struct socket *so);
286	SLIST_ENTRY(accept_filter) accf_next;
287};
288
289#ifdef MALLOC_DECLARE
290MALLOC_DECLARE(M_ACCF);
291MALLOC_DECLARE(M_PCB);
292MALLOC_DECLARE(M_SONAME);
293#endif
294
295extern int	maxsockets;
296extern u_long	sb_max;
297extern struct uma_zone *socket_zone;
298extern so_gen_t so_gencnt;
299
300struct mbuf;
301struct sockaddr;
302struct ucred;
303struct uio;
304
305/* 'which' values for socket upcalls. */
306#define	SO_RCV		1
307#define	SO_SND		2
308
309/* Return values for socket upcalls. */
310#define	SU_OK		0
311#define	SU_ISCONNECTED	1
312
313/*
314 * From uipc_socket and friends
315 */
316int	sockargs(struct mbuf **mp, caddr_t buf, int buflen, int type);
317int	getsockaddr(struct sockaddr **namp, caddr_t uaddr, size_t len);
318void	soabort(struct socket *so);
319int	soaccept(struct socket *so, struct sockaddr **nam);
320int	socheckuid(struct socket *so, uid_t uid);
321int	sobind(struct socket *so, struct sockaddr *nam, struct thread *td);
322int	soclose(struct socket *so);
323int	soconnect(struct socket *so, struct sockaddr *nam, struct thread *td);
324int	soconnect2(struct socket *so1, struct socket *so2);
325int	socow_setup(struct mbuf *m0, struct uio *uio);
326int	socreate(int dom, struct socket **aso, int type, int proto,
327	    struct ucred *cred, struct thread *td);
328int	sodisconnect(struct socket *so);
329struct	sockaddr *sodupsockaddr(const struct sockaddr *sa, int mflags);
330void	sofree(struct socket *so);
331void	sohasoutofband(struct socket *so);
332int	solisten(struct socket *so, int backlog, struct thread *td);
333void	solisten_proto(struct socket *so, int backlog);
334int	solisten_proto_check(struct socket *so);
335struct socket *
336	sonewconn(struct socket *head, int connstatus);
337
338
339int	sopoll(struct socket *so, int events, struct ucred *active_cred,
340	    struct thread *td);
341int	sopoll_generic(struct socket *so, int events,
342	    struct ucred *active_cred, struct thread *td);
343int	soreceive(struct socket *so, struct sockaddr **paddr, struct uio *uio,
344	    struct mbuf **mp0, struct mbuf **controlp, int *flagsp);
345int	soreceive_stream(struct socket *so, struct sockaddr **paddr,
346	    struct uio *uio, struct mbuf **mp0, struct mbuf **controlp,
347	    int *flagsp);
348int	soreceive_dgram(struct socket *so, struct sockaddr **paddr,
349	    struct uio *uio, struct mbuf **mp0, struct mbuf **controlp,
350	    int *flagsp);
351int	soreceive_generic(struct socket *so, struct sockaddr **paddr,
352	    struct uio *uio, struct mbuf **mp0, struct mbuf **controlp,
353	    int *flagsp);
354int	soreserve(struct socket *so, u_long sndcc, u_long rcvcc);
355void	sorflush(struct socket *so);
356int	sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
357	    struct mbuf *top, struct mbuf *control, int flags,
358	    struct thread *td);
359int	sosend_dgram(struct socket *so, struct sockaddr *addr,
360	    struct uio *uio, struct mbuf *top, struct mbuf *control,
361	    int flags, struct thread *td);
362int	sosend_generic(struct socket *so, struct sockaddr *addr,
363	    struct uio *uio, struct mbuf *top, struct mbuf *control,
364	    int flags, struct thread *td);
365int	soshutdown(struct socket *so, int how);
366void	sotoxsocket(struct socket *so, struct xsocket *xso);
367void	soupcall_clear(struct socket *so, int which);
368void	soupcall_set(struct socket *so, int which,
369	    int (*func)(struct socket *, void *, int), void *arg);
370void	sowakeup(struct socket *so, struct sockbuf *sb);
371int	selsocket(struct socket *so, int events, struct timeval *tv,
372	    struct thread *td);
373
374/*
375 * Accept filter functions (duh).
376 */
377int	accept_filt_add(struct accept_filter *filt);
378int	accept_filt_del(char *name);
379struct	accept_filter *accept_filt_get(char *name);
380#ifdef ACCEPT_FILTER_MOD
381#ifdef SYSCTL_DECL
382SYSCTL_DECL(_net_inet_accf);
383#endif
384int	accept_filt_generic_mod_event(module_t mod, int event, void *data);
385#endif
386
387#endif /* _KERNEL */
388
389#endif /* !_SYS_SOCKETVAR_H_ */
390