socketvar.h revision 191688
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: head/sys/sys/socketvar.h 191688 2009-04-30 13:36:26Z zec $
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
58/*-
59 * Locking key to struct socket:
60 * (a) constant after allocation, no locking required.
61 * (b) locked by SOCK_LOCK(so).
62 * (c) locked by SOCKBUF_LOCK(&so->so_rcv).
63 * (d) locked by SOCKBUF_LOCK(&so->so_snd).
64 * (e) locked by ACCEPT_LOCK().
65 * (f) not locked since integer reads/writes are atomic.
66 * (g) used only as a sleep/wakeup address, no value.
67 * (h) locked by global mutex so_global_mtx.
68 */
69struct socket {
70	int	so_count;		/* (b) reference count */
71	short	so_type;		/* (a) generic type, see socket.h */
72	short	so_options;		/* from socket call, see socket.h */
73	short	so_linger;		/* time to linger while closing */
74	short	so_state;		/* (b) internal state flags SS_* */
75	int	so_qstate;		/* (e) internal state flags SQ_* */
76	void	*so_pcb;		/* protocol control block */
77	struct	vnet *so_vnet;		/* network stack instance */
78	struct	protosw *so_proto;	/* (a) protocol handle */
79/*
80 * Variables for connection queuing.
81 * Socket where accepts occur is so_head in all subsidiary sockets.
82 * If so_head is 0, socket is not related to an accept.
83 * For head socket so_incomp queues partially completed connections,
84 * while so_comp is a queue of connections ready to be accepted.
85 * If a connection is aborted and it has so_head set, then
86 * it has to be pulled out of either so_incomp or so_comp.
87 * We allow connections to queue up based on current queue lengths
88 * and limit on number of queued connections for this socket.
89 */
90	struct	socket *so_head;	/* (e) back pointer to listen socket */
91	TAILQ_HEAD(, socket) so_incomp;	/* (e) queue of partial unaccepted connections */
92	TAILQ_HEAD(, socket) so_comp;	/* (e) queue of complete unaccepted connections */
93	TAILQ_ENTRY(socket) so_list;	/* (e) list of unaccepted connections */
94	u_short	so_qlen;		/* (e) number of unaccepted connections */
95	u_short	so_incqlen;		/* (e) number of unaccepted incomplete
96					   connections */
97	u_short	so_qlimit;		/* (e) max number queued connections */
98	short	so_timeo;		/* (g) connection timeout */
99	u_short	so_error;		/* (f) error affecting connection */
100	struct	sigio *so_sigio;	/* [sg] information for async I/O or
101					   out of band data (SIGURG) */
102	u_long	so_oobmark;		/* (c) chars to oob mark */
103	TAILQ_HEAD(, aiocblist) so_aiojobq; /* AIO ops waiting on socket */
104
105	struct sockbuf so_rcv, so_snd;
106
107	void	(*so_upcall)(struct socket *, void *, int);
108	void	*so_upcallarg;
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	int so_fibnum;		/* routing domain for this socket */
121};
122
123/*
124 * Global accept mutex to serialize access to accept queues and
125 * fields associated with multiple sockets.  This allows us to
126 * avoid defining a lock order between listen and accept sockets
127 * until such time as it proves to be a good idea.
128 */
129extern struct mtx accept_mtx;
130#define	ACCEPT_LOCK_ASSERT()		mtx_assert(&accept_mtx, MA_OWNED)
131#define	ACCEPT_UNLOCK_ASSERT()		mtx_assert(&accept_mtx, MA_NOTOWNED)
132#define	ACCEPT_LOCK()			mtx_lock(&accept_mtx)
133#define	ACCEPT_UNLOCK()			mtx_unlock(&accept_mtx)
134
135/*
136 * Per-socket mutex: we reuse the receive socket buffer mutex for space
137 * efficiency.  This decision should probably be revisited as we optimize
138 * locking for the socket code.
139 */
140#define	SOCK_MTX(_so)			SOCKBUF_MTX(&(_so)->so_rcv)
141#define	SOCK_LOCK(_so)			SOCKBUF_LOCK(&(_so)->so_rcv)
142#define	SOCK_OWNED(_so)			SOCKBUF_OWNED(&(_so)->so_rcv)
143#define	SOCK_UNLOCK(_so)		SOCKBUF_UNLOCK(&(_so)->so_rcv)
144#define	SOCK_LOCK_ASSERT(_so)		SOCKBUF_LOCK_ASSERT(&(_so)->so_rcv)
145
146/*
147 * Socket state bits stored in so_qstate.
148 */
149#define	SQ_INCOMP		0x0800	/* unaccepted, incomplete connection */
150#define	SQ_COMP			0x1000	/* unaccepted, complete connection */
151
152/*
153 * Externalized form of struct socket used by the sysctl(3) interface.
154 */
155struct xsocket {
156	size_t	xso_len;	/* length of this structure */
157	struct	socket *xso_so;	/* makes a convenient handle sometimes */
158	short	so_type;
159	short	so_options;
160	short	so_linger;
161	short	so_state;
162	caddr_t	so_pcb;		/* another convenient handle */
163	int	xso_protocol;
164	int	xso_family;
165	u_short	so_qlen;
166	u_short	so_incqlen;
167	u_short	so_qlimit;
168	short	so_timeo;
169	u_short	so_error;
170	pid_t	so_pgid;
171	u_long	so_oobmark;
172	struct xsockbuf so_rcv, so_snd;
173	uid_t	so_uid;		/* XXX */
174};
175
176#ifdef _KERNEL
177
178/*
179 * Macros for sockets and socket buffering.
180 */
181
182/*
183 * Flags to sblock().
184 */
185#define	SBL_WAIT	0x00000001	/* Wait if not immediately available. */
186#define	SBL_NOINTR	0x00000002	/* Force non-interruptible sleep. */
187#define	SBL_VALID	(SBL_WAIT | SBL_NOINTR)
188
189/*
190 * Do we need to notify the other side when I/O is possible?
191 */
192#define	sb_notify(sb)	(((sb)->sb_flags & (SB_WAIT | SB_SEL | SB_ASYNC | \
193    SB_UPCALL | SB_AIO | SB_KNOTE)) != 0)
194
195/* do we have to send all at once on a socket? */
196#define	sosendallatonce(so) \
197    ((so)->so_proto->pr_flags & PR_ATOMIC)
198
199/* can we read something from so? */
200#define	soreadable(so) \
201    ((so)->so_rcv.sb_cc >= (so)->so_rcv.sb_lowat || \
202	((so)->so_rcv.sb_state & SBS_CANTRCVMORE) || \
203	!TAILQ_EMPTY(&(so)->so_comp) || (so)->so_error)
204
205/* can we write something to so? */
206#define	sowriteable(so) \
207    ((sbspace(&(so)->so_snd) >= (so)->so_snd.sb_lowat && \
208	(((so)->so_state&SS_ISCONNECTED) || \
209	  ((so)->so_proto->pr_flags&PR_CONNREQUIRED)==0)) || \
210     ((so)->so_snd.sb_state & SBS_CANTSENDMORE) || \
211     (so)->so_error)
212
213/*
214 * soref()/sorele() ref-count the socket structure.  Note that you must
215 * still explicitly close the socket, but the last ref count will free
216 * the structure.
217 */
218#define	soref(so) do {							\
219	SOCK_LOCK_ASSERT(so);						\
220	++(so)->so_count;						\
221} while (0)
222
223#define	sorele(so) do {							\
224	ACCEPT_LOCK_ASSERT();						\
225	SOCK_LOCK_ASSERT(so);						\
226	if ((so)->so_count <= 0)					\
227		panic("sorele");					\
228	if (--(so)->so_count == 0)					\
229		sofree(so);						\
230	else {								\
231		SOCK_UNLOCK(so);					\
232		ACCEPT_UNLOCK();					\
233	}								\
234} while (0)
235
236#define	sotryfree(so) do {						\
237	ACCEPT_LOCK_ASSERT();						\
238	SOCK_LOCK_ASSERT(so);						\
239	if ((so)->so_count == 0)					\
240		sofree(so);						\
241	else {								\
242		SOCK_UNLOCK(so);					\
243		ACCEPT_UNLOCK();					\
244	}								\
245} while(0)
246
247/*
248 * In sorwakeup() and sowwakeup(), acquire the socket buffer lock to
249 * avoid a non-atomic test-and-wakeup.  However, sowakeup is
250 * responsible for releasing the lock if it is called.  We unlock only
251 * if we don't call into sowakeup.  If any code is introduced that
252 * directly invokes the underlying sowakeup() primitives, it must
253 * maintain the same semantics.
254 */
255#define	sorwakeup_locked(so) do {					\
256	SOCKBUF_LOCK_ASSERT(&(so)->so_rcv);				\
257	if (sb_notify(&(so)->so_rcv))					\
258		sowakeup((so), &(so)->so_rcv);	 			\
259	else								\
260		SOCKBUF_UNLOCK(&(so)->so_rcv);				\
261} while (0)
262
263#define	sorwakeup(so) do {						\
264	SOCKBUF_LOCK(&(so)->so_rcv);					\
265	sorwakeup_locked(so);						\
266} while (0)
267
268#define	sowwakeup_locked(so) do {					\
269	SOCKBUF_LOCK_ASSERT(&(so)->so_snd);				\
270	if (sb_notify(&(so)->so_snd))					\
271		sowakeup((so), &(so)->so_snd); 				\
272	else								\
273		SOCKBUF_UNLOCK(&(so)->so_snd);				\
274} while (0)
275
276#define	sowwakeup(so) do {						\
277	SOCKBUF_LOCK(&(so)->so_snd);					\
278	sowwakeup_locked(so);						\
279} while (0)
280
281struct accept_filter {
282	char	accf_name[16];
283	void	(*accf_callback)
284		(struct socket *so, void *arg, int waitflag);
285	void *	(*accf_create)
286		(struct socket *so, char *arg);
287	void	(*accf_destroy)
288		(struct socket *so);
289	SLIST_ENTRY(accept_filter) accf_next;
290};
291
292#ifdef MALLOC_DECLARE
293MALLOC_DECLARE(M_ACCF);
294MALLOC_DECLARE(M_PCB);
295MALLOC_DECLARE(M_SONAME);
296#endif
297
298extern int	maxsockets;
299extern u_long	sb_max;
300extern struct uma_zone *socket_zone;
301extern so_gen_t so_gencnt;
302
303struct mbuf;
304struct sockaddr;
305struct ucred;
306struct uio;
307
308/*
309 * From uipc_socket and friends
310 */
311int	sockargs(struct mbuf **mp, caddr_t buf, int buflen, int type);
312int	getsockaddr(struct sockaddr **namp, caddr_t uaddr, size_t len);
313void	soabort(struct socket *so);
314int	soaccept(struct socket *so, struct sockaddr **nam);
315int	socheckuid(struct socket *so, uid_t uid);
316int	sobind(struct socket *so, struct sockaddr *nam, struct thread *td);
317int	soclose(struct socket *so);
318int	soconnect(struct socket *so, struct sockaddr *nam, struct thread *td);
319int	soconnect2(struct socket *so1, struct socket *so2);
320int	socow_setup(struct mbuf *m0, struct uio *uio);
321int	socreate(int dom, struct socket **aso, int type, int proto,
322	    struct ucred *cred, struct thread *td);
323int	sodisconnect(struct socket *so);
324struct	sockaddr *sodupsockaddr(const struct sockaddr *sa, int mflags);
325void	sofree(struct socket *so);
326void	sohasoutofband(struct socket *so);
327int	solisten(struct socket *so, int backlog, struct thread *td);
328void	solisten_proto(struct socket *so, int backlog);
329int	solisten_proto_check(struct socket *so);
330struct socket *
331	sonewconn(struct socket *head, int connstatus);
332
333
334int	sopoll(struct socket *so, int events, struct ucred *active_cred,
335	    struct thread *td);
336int	sopoll_generic(struct socket *so, int events,
337	    struct ucred *active_cred, struct thread *td);
338int	soreceive(struct socket *so, struct sockaddr **paddr, struct uio *uio,
339	    struct mbuf **mp0, struct mbuf **controlp, int *flagsp);
340int	soreceive_dgram(struct socket *so, struct sockaddr **paddr,
341	    struct uio *uio, struct mbuf **mp0, struct mbuf **controlp,
342	    int *flagsp);
343int	soreceive_generic(struct socket *so, struct sockaddr **paddr,
344	    struct uio *uio, struct mbuf **mp0, struct mbuf **controlp,
345	    int *flagsp);
346int	soreserve(struct socket *so, u_long sndcc, u_long rcvcc);
347void	sorflush(struct socket *so);
348int	sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
349	    struct mbuf *top, struct mbuf *control, int flags,
350	    struct thread *td);
351int	sosend_dgram(struct socket *so, struct sockaddr *addr,
352	    struct uio *uio, struct mbuf *top, struct mbuf *control,
353	    int flags, struct thread *td);
354int	sosend_generic(struct socket *so, struct sockaddr *addr,
355	    struct uio *uio, struct mbuf *top, struct mbuf *control,
356	    int flags, struct thread *td);
357int	soshutdown(struct socket *so, int how);
358void	sotoxsocket(struct socket *so, struct xsocket *xso);
359void	sowakeup(struct socket *so, struct sockbuf *sb);
360int	selsocket(struct socket *so, int events, struct timeval *tv,
361	    struct thread *td);
362
363/*
364 * Accept filter functions (duh).
365 */
366int	accept_filt_add(struct accept_filter *filt);
367int	accept_filt_del(char *name);
368struct	accept_filter *accept_filt_get(char *name);
369#ifdef ACCEPT_FILTER_MOD
370#ifdef SYSCTL_DECL
371SYSCTL_DECL(_net_inet_accf);
372#endif
373int	accept_filt_generic_mod_event(module_t mod, int event, void *data);
374#endif
375
376#endif /* _KERNEL */
377
378#endif /* !_SYS_SOCKETVAR_H_ */
379