socketvar.h revision 129979
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 * $FreeBSD: head/sys/sys/socketvar.h 129979 2004-06-02 04:15:39Z rwatson $
31 */
32
33#ifndef _SYS_SOCKETVAR_H_
34#define _SYS_SOCKETVAR_H_
35
36#include <sys/queue.h>			/* for TAILQ macros */
37#include <sys/selinfo.h>		/* for struct selinfo */
38
39/*
40 * Kernel structure per socket.
41 * Contains send and receive buffer queues,
42 * handle on protocol and pointer to protocol
43 * private data and error information.
44 */
45typedef	u_quad_t so_gen_t;
46
47/*-
48 * Locking key to struct socket:
49 * (a) constant after allocation, no locking required.
50 * (b) locked by SOCK_LOCK(so).
51 * (c) locked by SOCKBUF_LOCK(&so->so_rcv).
52 * (d) locked by SOCKBUF_LOCK(&so->so_snd).
53 * (e) locked by ACCEPT_LOCK().
54 * (f) not locked since integer reads/writes are atomic.
55 * (g) used only as a sleep/wakeup address, no value.
56 */
57struct socket {
58	int	so_count;		/* reference count */
59	short	so_type;		/* (a) generic type, see socket.h */
60	short	so_options;		/* from socket call, see socket.h */
61	short	so_linger;		/* time to linger while closing */
62	short	so_state;		/* internal state flags SS_* */
63	int	so_qstate;		/* (e) internal state flags SQ_* */
64	void	*so_pcb;		/* protocol control block */
65	struct	protosw *so_proto;	/* (a) protocol handle */
66/*
67 * Variables for connection queuing.
68 * Socket where accepts occur is so_head in all subsidiary sockets.
69 * If so_head is 0, socket is not related to an accept.
70 * For head socket so_incomp queues partially completed connections,
71 * while so_comp is a queue of connections ready to be accepted.
72 * If a connection is aborted and it has so_head set, then
73 * it has to be pulled out of either so_incomp or so_comp.
74 * We allow connections to queue up based on current queue lengths
75 * and limit on number of queued connections for this socket.
76 */
77	struct	socket *so_head;	/* (e) back pointer to accept socket */
78	TAILQ_HEAD(, socket) so_incomp;	/* (e) queue of partial unaccepted connections */
79	TAILQ_HEAD(, socket) so_comp;	/* (e) queue of complete unaccepted connections */
80	TAILQ_ENTRY(socket) so_list;	/* (e) list of unaccepted connections */
81	short	so_qlen;		/* (e) number of unaccepted connections */
82	short	so_incqlen;		/* (e) number of unaccepted incomplete
83					   connections */
84	short	so_qlimit;		/* (e) max number queued connections */
85	short	so_timeo;		/* connection timeout */
86	u_short	so_error;		/* error affecting connection */
87	struct	sigio *so_sigio;	/* [sg] information for async I/O or
88					   out of band data (SIGURG) */
89	u_long	so_oobmark;		/* chars to oob mark */
90	TAILQ_HEAD(, aiocblist) so_aiojobq; /* AIO ops waiting on socket */
91/*
92 * Variables for socket buffering.
93 */
94	struct sockbuf {
95		struct	selinfo sb_sel;	/* process selecting read/write */
96#define	sb_startzero	sb_mb
97		struct	mbuf *sb_mb;	/* the mbuf chain */
98		struct	mbuf *sb_mbtail; /* the last mbuf in the chain */
99		struct	mbuf *sb_lastrecord;	/* first mbuf of last record in
100						 * socket buffer */
101		u_int	sb_cc;		/* actual chars in buffer */
102		u_int	sb_hiwat;	/* max actual char count */
103		u_int	sb_mbcnt;	/* chars of mbufs used */
104		u_int	sb_mbmax;	/* max chars of mbufs to use */
105		u_int	sb_ctl;		/* non-data chars in buffer */
106		int	sb_lowat;	/* low water mark */
107		int	sb_timeo;	/* timeout for read/write */
108		short	sb_flags;	/* flags, see below */
109	} so_rcv, so_snd;
110#define	SB_MAX		(256*1024)	/* default for max chars in sockbuf */
111#define	SB_LOCK		0x01		/* lock on data queue */
112#define	SB_WANT		0x02		/* someone is waiting to lock */
113#define	SB_WAIT		0x04		/* someone is waiting for data/space */
114#define	SB_SEL		0x08		/* someone is selecting */
115#define	SB_ASYNC	0x10		/* ASYNC I/O, need signals */
116#define	SB_UPCALL	0x20		/* someone wants an upcall */
117#define	SB_NOINTR	0x40		/* operations not interruptible */
118#define SB_AIO		0x80		/* AIO operations queued */
119#define SB_KNOTE	0x100		/* kernel note attached */
120
121	void	(*so_upcall)(struct socket *, void *, int);
122	void	*so_upcallarg;
123	struct	ucred *so_cred;		/* user credentials */
124	struct	label *so_label;	/* MAC label for socket */
125	struct	label *so_peerlabel;	/* cached MAC label for socket peer */
126	/* NB: generation count must not be first; easiest to make it last. */
127	so_gen_t so_gencnt;		/* generation count */
128	void	*so_emuldata;		/* private data for emulators */
129 	struct so_accf {
130		struct	accept_filter *so_accept_filter;
131		void	*so_accept_filter_arg;	/* saved filter args */
132		char	*so_accept_filter_str;	/* saved user args */
133	} *so_accf;
134};
135
136#define SB_EMPTY_FIXUP(sb) do {						\
137	if ((sb)->sb_mb == NULL) {					\
138		(sb)->sb_mbtail = NULL;					\
139		(sb)->sb_lastrecord = NULL;				\
140	}								\
141} while (/*CONSTCOND*/0)
142
143/*
144 * Global accept mutex to serialize access to accept queues and
145 * fields associated with multiple sockets.  This allows us to
146 * avoid defining a lock order between listen and accept sockets
147 * until such time as it proves to be a good idea.
148 */
149extern struct mtx accept_mtx;
150#define ACCEPT_LOCK()			mtx_lock(&accept_mtx)
151#define ACCEPT_UNLOCK()			mtx_unlock(&accept_mtx)
152
153/*
154 * Socket state bits.
155 */
156#define	SS_NOFDREF		0x0001	/* no file table ref any more */
157#define	SS_ISCONNECTED		0x0002	/* socket connected to a peer */
158#define	SS_ISCONNECTING		0x0004	/* in process of connecting to peer */
159#define	SS_ISDISCONNECTING	0x0008	/* in process of disconnecting */
160#define	SS_CANTSENDMORE		0x0010	/* can't send more data to peer */
161#define	SS_CANTRCVMORE		0x0020	/* can't receive more data from peer */
162#define	SS_RCVATMARK		0x0040	/* at mark on input */
163
164#define	SS_NBIO			0x0100	/* non-blocking ops */
165#define	SS_ASYNC		0x0200	/* async i/o notify */
166#define	SS_ISCONFIRMING		0x0400	/* deciding to accept connection req */
167
168#define	SS_ISDISCONNECTED	0x2000	/* socket disconnected from peer */
169
170/*
171 * Socket state bits stored in so_qstate.
172 */
173#define	SQ_INCOMP		0x0800	/* unaccepted, incomplete connection */
174#define	SQ_COMP			0x1000	/* unaccepted, complete connection */
175
176/*
177 * Externalized form of struct socket used by the sysctl(3) interface.
178 */
179struct xsocket {
180	size_t	xso_len;	/* length of this structure */
181	struct	socket *xso_so;	/* makes a convenient handle sometimes */
182	short	so_type;
183	short	so_options;
184	short	so_linger;
185	short	so_state;
186	caddr_t	so_pcb;		/* another convenient handle */
187	int	xso_protocol;
188	int	xso_family;
189	short	so_qlen;
190	short	so_incqlen;
191	short	so_qlimit;
192	short	so_timeo;
193	u_short	so_error;
194	pid_t	so_pgid;
195	u_long	so_oobmark;
196	struct xsockbuf {
197		u_int	sb_cc;
198		u_int	sb_hiwat;
199		u_int	sb_mbcnt;
200		u_int	sb_mbmax;
201		int	sb_lowat;
202		int	sb_timeo;
203		short	sb_flags;
204	} so_rcv, so_snd;
205	uid_t	so_uid;		/* XXX */
206};
207
208/*
209 * Macros for sockets and socket buffering.
210 */
211
212/*
213 * Do we need to notify the other side when I/O is possible?
214 */
215#define	sb_notify(sb)	(((sb)->sb_flags & (SB_WAIT | SB_SEL | SB_ASYNC | \
216    SB_UPCALL | SB_AIO | SB_KNOTE)) != 0)
217
218/*
219 * How much space is there in a socket buffer (so->so_snd or so->so_rcv)?
220 * This is problematical if the fields are unsigned, as the space might
221 * still be negative (cc > hiwat or mbcnt > mbmax).  Should detect
222 * overflow and return 0.  Should use "lmin" but it doesn't exist now.
223 */
224#define	sbspace(sb) \
225    ((long) imin((int)((sb)->sb_hiwat - (sb)->sb_cc), \
226	 (int)((sb)->sb_mbmax - (sb)->sb_mbcnt)))
227
228/* do we have to send all at once on a socket? */
229#define	sosendallatonce(so) \
230    ((so)->so_proto->pr_flags & PR_ATOMIC)
231
232/* can we read something from so? */
233#define	soreadable(so) \
234    ((so)->so_rcv.sb_cc >= (so)->so_rcv.sb_lowat || \
235	((so)->so_state & SS_CANTRCVMORE) || \
236	!TAILQ_EMPTY(&(so)->so_comp) || (so)->so_error)
237
238/* can we write something to so? */
239#define	sowriteable(so) \
240    ((sbspace(&(so)->so_snd) >= (so)->so_snd.sb_lowat && \
241	(((so)->so_state&SS_ISCONNECTED) || \
242	  ((so)->so_proto->pr_flags&PR_CONNREQUIRED)==0)) || \
243     ((so)->so_state & SS_CANTSENDMORE) || \
244     (so)->so_error)
245
246/* adjust counters in sb reflecting allocation of m */
247#define	sballoc(sb, m) { \
248	(sb)->sb_cc += (m)->m_len; \
249	if ((m)->m_type != MT_DATA && (m)->m_type != MT_HEADER && \
250	    (m)->m_type != MT_OOBDATA) \
251		(sb)->sb_ctl += (m)->m_len; \
252	(sb)->sb_mbcnt += MSIZE; \
253	if ((m)->m_flags & M_EXT) \
254		(sb)->sb_mbcnt += (m)->m_ext.ext_size; \
255}
256
257/* adjust counters in sb reflecting freeing of m */
258#define	sbfree(sb, m) { \
259	(sb)->sb_cc -= (m)->m_len; \
260	if ((m)->m_type != MT_DATA && (m)->m_type != MT_HEADER && \
261	    (m)->m_type != MT_OOBDATA) \
262		(sb)->sb_ctl -= (m)->m_len; \
263	(sb)->sb_mbcnt -= MSIZE; \
264	if ((m)->m_flags & M_EXT) \
265		(sb)->sb_mbcnt -= (m)->m_ext.ext_size; \
266}
267
268/*
269 * Set lock on sockbuf sb; sleep if lock is already held.
270 * Unless SB_NOINTR is set on sockbuf, sleep is interruptible.
271 * Returns error without lock if sleep is interrupted.
272 */
273#define sblock(sb, wf) ((sb)->sb_flags & SB_LOCK ? \
274		(((wf) == M_WAITOK) ? sb_lock(sb) : EWOULDBLOCK) : \
275		((sb)->sb_flags |= SB_LOCK), 0)
276
277/* release lock on sockbuf sb */
278#define	sbunlock(sb) { \
279	(sb)->sb_flags &= ~SB_LOCK; \
280	if ((sb)->sb_flags & SB_WANT) { \
281		(sb)->sb_flags &= ~SB_WANT; \
282		wakeup(&(sb)->sb_flags); \
283	} \
284}
285
286/*
287 * soref()/sorele() ref-count the socket structure.  Note that you must
288 * still explicitly close the socket, but the last ref count will free
289 * the structure.
290 */
291#define soref(so)	do {			\
292				++(so)->so_count; \
293			} while (0)
294
295#define sorele(so)	do {				\
296				if ((so)->so_count <= 0)	\
297					panic("sorele");\
298				if (--(so)->so_count == 0)\
299					sofree(so);	\
300			} while (0)
301
302#define sotryfree(so)	do {				\
303				if ((so)->so_count == 0)	\
304					sofree(so);	\
305			} while(0)
306
307#define	sorwakeup(so)	do {					\
308				if (sb_notify(&(so)->so_rcv))	\
309					sowakeup((so), &(so)->so_rcv); \
310			} while (0)
311
312#define	sowwakeup(so)	do {					\
313				if (sb_notify(&(so)->so_snd))	\
314					sowakeup((so), &(so)->so_snd); \
315			} while (0)
316
317#ifdef _KERNEL
318
319/*
320 * Argument structure for sosetopt et seq.  This is in the KERNEL
321 * section because it will never be visible to user code.
322 */
323enum sopt_dir { SOPT_GET, SOPT_SET };
324struct sockopt {
325	enum	sopt_dir sopt_dir; /* is this a get or a set? */
326	int	sopt_level;	/* second arg of [gs]etsockopt */
327	int	sopt_name;	/* third arg of [gs]etsockopt */
328	void   *sopt_val;	/* fourth arg of [gs]etsockopt */
329	size_t	sopt_valsize;	/* (almost) fifth arg of [gs]etsockopt */
330	struct	thread *sopt_td; /* calling thread or null if kernel */
331};
332
333struct accept_filter {
334	char	accf_name[16];
335	void	(*accf_callback)
336		(struct socket *so, void *arg, int waitflag);
337	void *	(*accf_create)
338		(struct socket *so, char *arg);
339	void	(*accf_destroy)
340		(struct socket *so);
341	SLIST_ENTRY(accept_filter) accf_next;
342};
343
344#ifdef MALLOC_DECLARE
345MALLOC_DECLARE(M_ACCF);
346MALLOC_DECLARE(M_PCB);
347MALLOC_DECLARE(M_SONAME);
348#endif
349
350extern int	maxsockets;
351extern u_long	sb_max;
352extern struct uma_zone *socket_zone;
353extern so_gen_t so_gencnt;
354
355struct mbuf;
356struct sockaddr;
357struct ucred;
358struct uio;
359
360/*
361 * From uipc_socket and friends
362 */
363int	sockargs(struct mbuf **mp, caddr_t buf, int buflen, int type);
364int	getsockaddr(struct sockaddr **namp, caddr_t uaddr, size_t len);
365void	sbappend(struct sockbuf *sb, struct mbuf *m);
366void	sbappendstream(struct sockbuf *sb, struct mbuf *m);
367int	sbappendaddr(struct sockbuf *sb, struct sockaddr *asa,
368	    struct mbuf *m0, struct mbuf *control);
369int	sbappendcontrol(struct sockbuf *sb, struct mbuf *m0,
370	    struct mbuf *control);
371void	sbappendrecord(struct sockbuf *sb, struct mbuf *m0);
372void	sbcheck(struct sockbuf *sb);
373void	sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n);
374struct mbuf *
375	sbcreatecontrol(caddr_t p, int size, int type, int level);
376void	sbdrop(struct sockbuf *sb, int len);
377void	sbdroprecord(struct sockbuf *sb);
378void	sbflush(struct sockbuf *sb);
379void	sbinsertoob(struct sockbuf *sb, struct mbuf *m0);
380void	sbrelease(struct sockbuf *sb, struct socket *so);
381int	sbreserve(struct sockbuf *sb, u_long cc, struct socket *so,
382	    struct thread *td);
383void	sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb);
384int	sbwait(struct sockbuf *sb);
385int	sb_lock(struct sockbuf *sb);
386int	soabort(struct socket *so);
387int	soaccept(struct socket *so, struct sockaddr **nam);
388struct	socket *soalloc(int mflags);
389int	socheckuid(struct socket *so, uid_t uid);
390int	sobind(struct socket *so, struct sockaddr *nam, struct thread *td);
391void	socantrcvmore(struct socket *so);
392void	socantsendmore(struct socket *so);
393int	soclose(struct socket *so);
394int	soconnect(struct socket *so, struct sockaddr *nam, struct thread *td);
395int	soconnect2(struct socket *so1, struct socket *so2);
396int	socow_setup(struct mbuf *m0, struct uio *uio);
397int	socreate(int dom, struct socket **aso, int type, int proto,
398	    struct ucred *cred, struct thread *td);
399void	sodealloc(struct socket *so);
400int	sodisconnect(struct socket *so);
401struct	sockaddr *sodupsockaddr(const struct sockaddr *sa, int mflags);
402void	sofree(struct socket *so);
403int	sogetopt(struct socket *so, struct sockopt *sopt);
404void	sohasoutofband(struct socket *so);
405void	soisconnected(struct socket *so);
406void	soisconnecting(struct socket *so);
407void	soisdisconnected(struct socket *so);
408void	soisdisconnecting(struct socket *so);
409int	solisten(struct socket *so, int backlog, struct thread *td);
410struct socket *
411	sonewconn(struct socket *head, int connstatus);
412int	sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen);
413int	sooptcopyout(struct sockopt *sopt, const void *buf, size_t len);
414
415/* XXX; prepare mbuf for (__FreeBSD__ < 3) routines. */
416int	soopt_getm(struct sockopt *sopt, struct mbuf **mp);
417int	soopt_mcopyin(struct sockopt *sopt, struct mbuf *m);
418int	soopt_mcopyout(struct sockopt *sopt, struct mbuf *m);
419
420int	sopoll(struct socket *so, int events, struct ucred *active_cred,
421	    struct thread *td);
422int	soreceive(struct socket *so, struct sockaddr **paddr, struct uio *uio,
423	    struct mbuf **mp0, struct mbuf **controlp, int *flagsp);
424int	soreserve(struct socket *so, u_long sndcc, u_long rcvcc);
425void	sorflush(struct socket *so);
426int	sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
427	    struct mbuf *top, struct mbuf *control, int flags,
428	    struct thread *td);
429int	sosetopt(struct socket *so, struct sockopt *sopt);
430int	soshutdown(struct socket *so, int how);
431void	sotoxsocket(struct socket *so, struct xsocket *xso);
432void	sowakeup(struct socket *so, struct sockbuf *sb);
433
434#ifdef SOCKBUF_DEBUG
435void	sblastrecordchk(struct sockbuf *, const char *, int);
436#define	SBLASTRECORDCHK(sb)	sblastrecordchk((sb), __FILE__, __LINE__)
437
438void	sblastmbufchk(struct sockbuf *, const char *, int);
439#define	SBLASTMBUFCHK(sb)	sblastmbufchk((sb), __FILE__, __LINE__)
440#else
441#define	SBLASTRECORDCHK(sb)      /* nothing */
442#define	SBLASTMBUFCHK(sb)        /* nothing */
443#endif /* SOCKBUF_DEBUG */
444
445/*
446 * Accept filter functions (duh).
447 */
448int	accept_filt_add(struct accept_filter *filt);
449int	accept_filt_del(char *name);
450struct	accept_filter *accept_filt_get(char *name);
451#ifdef ACCEPT_FILTER_MOD
452#ifdef SYSCTL_DECL
453SYSCTL_DECL(_net_inet_accf);
454#endif
455int	accept_filt_generic_mod_event(module_t mod, int event, void *data);
456#endif
457
458#endif /* _KERNEL */
459
460#endif /* !_SYS_SOCKETVAR_H_ */
461