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uipc_syscalls.c revision 1.149
      1 /*	$NetBSD: uipc_syscalls.c,v 1.149 2011/12/20 23:56:28 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Andrew Doran.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1982, 1986, 1989, 1990, 1993
     34  *	The Regents of the University of California.  All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  * 3. Neither the name of the University nor the names of its contributors
     45  *    may be used to endorse or promote products derived from this software
     46  *    without specific prior written permission.
     47  *
     48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     58  * SUCH DAMAGE.
     59  *
     60  *	@(#)uipc_syscalls.c	8.6 (Berkeley) 2/14/95
     61  */
     62 
     63 #include <sys/cdefs.h>
     64 __KERNEL_RCSID(0, "$NetBSD: uipc_syscalls.c,v 1.149 2011/12/20 23:56:28 christos Exp $");
     65 
     66 #include "opt_pipe.h"
     67 
     68 #include <sys/param.h>
     69 #include <sys/systm.h>
     70 #include <sys/filedesc.h>
     71 #include <sys/proc.h>
     72 #include <sys/file.h>
     73 #include <sys/buf.h>
     74 #define MBUFTYPES
     75 #include <sys/mbuf.h>
     76 #include <sys/protosw.h>
     77 #include <sys/socket.h>
     78 #include <sys/socketvar.h>
     79 #include <sys/signalvar.h>
     80 #include <sys/un.h>
     81 #include <sys/ktrace.h>
     82 #include <sys/event.h>
     83 #include <sys/kauth.h>
     84 
     85 #include <sys/mount.h>
     86 #include <sys/syscallargs.h>
     87 
     88 /*
     89  * System call interface to the socket abstraction.
     90  */
     91 extern const struct fileops socketops;
     92 
     93 int
     94 sys___socket30(struct lwp *l, const struct sys___socket30_args *uap, register_t *retval)
     95 {
     96 	/* {
     97 		syscallarg(int)	domain;
     98 		syscallarg(int)	type;
     99 		syscallarg(int)	protocol;
    100 	} */
    101 	int		fd, error;
    102 
    103 	error = fsocreate(SCARG(uap, domain), NULL, SCARG(uap, type),
    104 			 SCARG(uap, protocol), l, &fd);
    105 	if (error == 0)
    106 		*retval = fd;
    107 	return error;
    108 }
    109 
    110 /* ARGSUSED */
    111 int
    112 sys_bind(struct lwp *l, const struct sys_bind_args *uap, register_t *retval)
    113 {
    114 	/* {
    115 		syscallarg(int)				s;
    116 		syscallarg(const struct sockaddr *)	name;
    117 		syscallarg(unsigned int)		namelen;
    118 	} */
    119 	struct mbuf	*nam;
    120 	int		error;
    121 
    122 	error = sockargs(&nam, SCARG(uap, name), SCARG(uap, namelen),
    123 	    MT_SONAME);
    124 	if (error)
    125 		return error;
    126 
    127 	return do_sys_bind(l, SCARG(uap, s), nam);
    128 }
    129 
    130 int
    131 do_sys_bind(struct lwp *l, int fd, struct mbuf *nam)
    132 {
    133 	struct socket	*so;
    134 	int		error;
    135 
    136 	if ((error = fd_getsock(fd, &so)) != 0) {
    137 		m_freem(nam);
    138 		return (error);
    139 	}
    140 	MCLAIM(nam, so->so_mowner);
    141 	error = sobind(so, nam, l);
    142 	m_freem(nam);
    143 	fd_putfile(fd);
    144 	return error;
    145 }
    146 
    147 /* ARGSUSED */
    148 int
    149 sys_listen(struct lwp *l, const struct sys_listen_args *uap, register_t *retval)
    150 {
    151 	/* {
    152 		syscallarg(int)	s;
    153 		syscallarg(int)	backlog;
    154 	} */
    155 	struct socket	*so;
    156 	int		error;
    157 
    158 	if ((error = fd_getsock(SCARG(uap, s), &so)) != 0)
    159 		return (error);
    160 	error = solisten(so, SCARG(uap, backlog), l);
    161 	fd_putfile(SCARG(uap, s));
    162 	return error;
    163 }
    164 
    165 int
    166 do_sys_accept(struct lwp *l, int sock, struct mbuf **name, register_t *new_sock,
    167     const sigset_t *mask, int flags, int clrflags)
    168 {
    169 	file_t		*fp, *fp2;
    170 	struct mbuf	*nam;
    171 	int		error, fd;
    172 	struct socket	*so, *so2;
    173 	short		wakeup_state = 0;
    174 
    175 	if ((fp = fd_getfile(sock)) == NULL)
    176 		return (EBADF);
    177 	if (fp->f_type != DTYPE_SOCKET) {
    178 		fd_putfile(sock);
    179 		return (ENOTSOCK);
    180 	}
    181 	if ((error = fd_allocfile(&fp2, &fd)) != 0) {
    182 		fd_putfile(sock);
    183 		return (error);
    184 	}
    185 	nam = m_get(M_WAIT, MT_SONAME);
    186 	*new_sock = fd;
    187 	so = fp->f_data;
    188 	solock(so);
    189 
    190 	if (__predict_false(mask))
    191 		sigsuspendsetup(l, mask);
    192 
    193 	if (!(so->so_proto->pr_flags & PR_LISTEN)) {
    194 		error = EOPNOTSUPP;
    195 		goto bad;
    196 	}
    197 	if ((so->so_options & SO_ACCEPTCONN) == 0) {
    198 		error = EINVAL;
    199 		goto bad;
    200 	}
    201 	if ((so->so_state & SS_NBIO) && so->so_qlen == 0) {
    202 		error = EWOULDBLOCK;
    203 		goto bad;
    204 	}
    205 	while (so->so_qlen == 0 && so->so_error == 0) {
    206 		if (so->so_state & SS_CANTRCVMORE) {
    207 			so->so_error = ECONNABORTED;
    208 			break;
    209 		}
    210 		if (wakeup_state & SS_RESTARTSYS) {
    211 			error = ERESTART;
    212 			goto bad;
    213 		}
    214 		error = sowait(so, true, 0);
    215 		if (error) {
    216 			goto bad;
    217 		}
    218 		wakeup_state = so->so_state;
    219 	}
    220 	if (so->so_error) {
    221 		error = so->so_error;
    222 		so->so_error = 0;
    223 		goto bad;
    224 	}
    225 	/* connection has been removed from the listen queue */
    226 	KNOTE(&so->so_rcv.sb_sel.sel_klist, NOTE_SUBMIT);
    227 	so2 = TAILQ_FIRST(&so->so_q);
    228 	if (soqremque(so2, 1) == 0)
    229 		panic("accept");
    230 	fp2->f_type = DTYPE_SOCKET;
    231 	fp2->f_flag = (fp->f_flag & ~clrflags) |
    232 	    ((flags & SOCK_NONBLOCK) ? FNONBLOCK : 0);
    233 	fp2->f_ops = &socketops;
    234 	fp2->f_data = so2;
    235 	error = soaccept(so2, nam);
    236 	so2->so_cred = kauth_cred_dup(so->so_cred);
    237 	sounlock(so);
    238 	if (error) {
    239 		/* an error occurred, free the file descriptor and mbuf */
    240 		m_freem(nam);
    241 		mutex_enter(&fp2->f_lock);
    242 		fp2->f_count++;
    243 		mutex_exit(&fp2->f_lock);
    244 		closef(fp2);
    245 		fd_abort(curproc, NULL, fd);
    246 	} else {
    247 		fd_set_exclose(l, fd, (flags & SOCK_CLOEXEC) != 0);
    248 		fd_affix(curproc, fp2, fd);
    249 		*name = nam;
    250 	}
    251 	fd_putfile(sock);
    252 	if (__predict_false(mask))
    253 		sigsuspendteardown(l);
    254 	return (error);
    255  bad:
    256  	sounlock(so);
    257  	m_freem(nam);
    258 	fd_putfile(sock);
    259  	fd_abort(curproc, fp2, fd);
    260 	if (__predict_false(mask))
    261 		sigsuspendteardown(l);
    262  	return (error);
    263 }
    264 
    265 int
    266 sys_accept(struct lwp *l, const struct sys_accept_args *uap, register_t *retval)
    267 {
    268 	/* {
    269 		syscallarg(int)			s;
    270 		syscallarg(struct sockaddr *)	name;
    271 		syscallarg(unsigned int *)	anamelen;
    272 	} */
    273 	int error, fd;
    274 	struct mbuf *name;
    275 
    276 	error = do_sys_accept(l, SCARG(uap, s), &name, retval, NULL, 0, 0);
    277 	if (error != 0)
    278 		return error;
    279 	error = copyout_sockname(SCARG(uap, name), SCARG(uap, anamelen),
    280 	    MSG_LENUSRSPACE, name);
    281 	if (name != NULL)
    282 		m_free(name);
    283 	if (error != 0) {
    284 		fd = (int)*retval;
    285 		if (fd_getfile(fd) != NULL)
    286 			(void)fd_close(fd);
    287 	}
    288 	return error;
    289 }
    290 
    291 int
    292 sys_paccept(struct lwp *l, const struct sys_paccept_args *uap,
    293     register_t *retval)
    294 {
    295 	/* {
    296 		syscallarg(int)			s;
    297 		syscallarg(struct sockaddr *)	name;
    298 		syscallarg(unsigned int *)	anamelen;
    299 		syscallarg(const sigset_t *)	mask;
    300 		syscallarg(int)			flags;
    301 	} */
    302 	int error, fd;
    303 	struct mbuf *name;
    304 	sigset_t *mask, amask;
    305 
    306 	if (SCARG(uap, mask) != NULL) {
    307 		error = copyin(SCARG(uap, mask), &amask, sizeof(amask));
    308 		if (error)
    309 			return error;
    310 		mask = &amask;
    311 	} else
    312 		mask = NULL;
    313 
    314 	error = do_sys_accept(l, SCARG(uap, s), &name, retval, mask,
    315 	    SCARG(uap, flags), FNONBLOCK);
    316 	if (error != 0)
    317 		return error;
    318 	error = copyout_sockname(SCARG(uap, name), SCARG(uap, anamelen),
    319 	    MSG_LENUSRSPACE, name);
    320 	if (name != NULL)
    321 		m_free(name);
    322 	if (error != 0) {
    323 		fd = (int)*retval;
    324 		if (fd_getfile(fd) != NULL)
    325 			(void)fd_close(fd);
    326 	}
    327 	return error;
    328 }
    329 
    330 /* ARGSUSED */
    331 int
    332 sys_connect(struct lwp *l, const struct sys_connect_args *uap, register_t *retval)
    333 {
    334 	/* {
    335 		syscallarg(int)				s;
    336 		syscallarg(const struct sockaddr *)	name;
    337 		syscallarg(unsigned int)		namelen;
    338 	} */
    339 	int		error;
    340 	struct mbuf	*nam;
    341 
    342 	error = sockargs(&nam, SCARG(uap, name), SCARG(uap, namelen),
    343 	    MT_SONAME);
    344 	if (error)
    345 		return error;
    346 	return do_sys_connect(l,  SCARG(uap, s), nam);
    347 }
    348 
    349 int
    350 do_sys_connect(struct lwp *l, int fd, struct mbuf *nam)
    351 {
    352 	struct socket	*so;
    353 	int		error;
    354 	int		interrupted = 0;
    355 
    356 	if ((error = fd_getsock(fd, &so)) != 0) {
    357 		m_freem(nam);
    358 		return (error);
    359 	}
    360 	solock(so);
    361 	MCLAIM(nam, so->so_mowner);
    362 	if ((so->so_state & SS_ISCONNECTING) != 0) {
    363 		error = EALREADY;
    364 		goto out;
    365 	}
    366 
    367 	error = soconnect(so, nam, l);
    368 	if (error)
    369 		goto bad;
    370 	if ((so->so_state & SS_NBIO) && (so->so_state & SS_ISCONNECTING) != 0) {
    371 		error = EINPROGRESS;
    372 		goto out;
    373 	}
    374 	while ((so->so_state & SS_ISCONNECTING) != 0 && so->so_error == 0) {
    375 		error = sowait(so, true, 0);
    376 		if (__predict_false((so->so_state & SS_ISABORTING) != 0)) {
    377 			error = EPIPE;
    378 			interrupted = 1;
    379 			break;
    380 		}
    381 		if (error) {
    382 			if (error == EINTR || error == ERESTART)
    383 				interrupted = 1;
    384 			break;
    385 		}
    386 	}
    387 	if (error == 0) {
    388 		error = so->so_error;
    389 		so->so_error = 0;
    390 	}
    391  bad:
    392 	if (!interrupted)
    393 		so->so_state &= ~SS_ISCONNECTING;
    394 	if (error == ERESTART)
    395 		error = EINTR;
    396  out:
    397  	sounlock(so);
    398  	fd_putfile(fd);
    399 	m_freem(nam);
    400 	return (error);
    401 }
    402 
    403 static int
    404 makesocket(struct lwp *l, file_t **fp, int *fd, int flags, int type,
    405     int domain, int proto, struct socket *soo)
    406 {
    407 	int error;
    408 	struct socket *so;
    409 	int fnonblock = (flags & SOCK_NONBLOCK) ? FNONBLOCK : 0;
    410 
    411 	if ((error = socreate(domain, &so, type, proto, l, soo)) != 0)
    412 		return error;
    413 
    414 	if ((error = fd_allocfile(fp, fd)) != 0) {
    415 		soclose(so);
    416 		return error;
    417 	}
    418 	fd_set_exclose(l, *fd, (flags & SOCK_CLOEXEC) != 0);
    419 	(*fp)->f_flag = FREAD|FWRITE|fnonblock;
    420 	(*fp)->f_type = DTYPE_SOCKET;
    421 	(*fp)->f_ops = &socketops;
    422 	(*fp)->f_data = so;
    423 	return 0;
    424 }
    425 
    426 int
    427 sys_socketpair(struct lwp *l, const struct sys_socketpair_args *uap,
    428     register_t *retval)
    429 {
    430 	/* {
    431 		syscallarg(int)		domain;
    432 		syscallarg(int)		type;
    433 		syscallarg(int)		protocol;
    434 		syscallarg(int *)	rsv;
    435 	} */
    436 	file_t		*fp1, *fp2;
    437 	struct socket	*so1, *so2;
    438 	int		fd, error, sv[2];
    439 	proc_t		*p;
    440 	int		flags = SCARG(uap, type) & SOCK_FLAGS_MASK;
    441 	int		type = SCARG(uap, type) & ~SOCK_FLAGS_MASK;
    442 	int		domain = SCARG(uap, domain);
    443 	int		proto = SCARG(uap, protocol);
    444 
    445 	p = curproc;
    446 
    447 	error = makesocket(l, &fp1, &fd, flags, type, domain, proto, NULL);
    448 	if (error)
    449 		return error;
    450 	so1 = fp1->f_data;
    451 	sv[0] = fd;
    452 
    453 	error = makesocket(l, &fp2, &fd, flags, type, domain, proto, so1);
    454 	if (error)
    455 		goto out;
    456 	so2 = fp2->f_data;
    457 	sv[1] = fd;
    458 
    459 	solock(so1);
    460 	error = soconnect2(so1, so2);
    461 	if (error == 0 && type == SOCK_DGRAM) {
    462 		/*
    463 		 * Datagram socket connection is asymmetric.
    464 		 */
    465 		error = soconnect2(so2, so1);
    466 	}
    467 	sounlock(so1);
    468 
    469 	if (error == 0)
    470 		error = copyout(sv, SCARG(uap, rsv), sizeof(sv));
    471 	if (error == 0) {
    472 		fd_affix(p, fp2, sv[1]);
    473 		fd_affix(p, fp1, sv[0]);
    474 		return 0;
    475 	}
    476 	fd_abort(p, fp2, sv[1]);
    477 	(void)soclose(so2);
    478 out:
    479 	fd_abort(p, fp1, sv[0]);
    480 	(void)soclose(so1);
    481 	return error;
    482 }
    483 
    484 int
    485 sys_sendto(struct lwp *l, const struct sys_sendto_args *uap, register_t *retval)
    486 {
    487 	/* {
    488 		syscallarg(int)				s;
    489 		syscallarg(const void *)		buf;
    490 		syscallarg(size_t)			len;
    491 		syscallarg(int)				flags;
    492 		syscallarg(const struct sockaddr *)	to;
    493 		syscallarg(unsigned int)		tolen;
    494 	} */
    495 	struct msghdr	msg;
    496 	struct iovec	aiov;
    497 
    498 	msg.msg_name = __UNCONST(SCARG(uap, to)); /* XXXUNCONST kills const */
    499 	msg.msg_namelen = SCARG(uap, tolen);
    500 	msg.msg_iov = &aiov;
    501 	msg.msg_iovlen = 1;
    502 	msg.msg_control = NULL;
    503 	msg.msg_flags = 0;
    504 	aiov.iov_base = __UNCONST(SCARG(uap, buf)); /* XXXUNCONST kills const */
    505 	aiov.iov_len = SCARG(uap, len);
    506 	return do_sys_sendmsg(l, SCARG(uap, s), &msg, SCARG(uap, flags), retval);
    507 }
    508 
    509 int
    510 sys_sendmsg(struct lwp *l, const struct sys_sendmsg_args *uap, register_t *retval)
    511 {
    512 	/* {
    513 		syscallarg(int)				s;
    514 		syscallarg(const struct msghdr *)	msg;
    515 		syscallarg(int)				flags;
    516 	} */
    517 	struct msghdr	msg;
    518 	int		error;
    519 
    520 	error = copyin(SCARG(uap, msg), &msg, sizeof(msg));
    521 	if (error)
    522 		return (error);
    523 
    524 	msg.msg_flags = MSG_IOVUSRSPACE;
    525 	return do_sys_sendmsg(l, SCARG(uap, s), &msg, SCARG(uap, flags), retval);
    526 }
    527 
    528 int
    529 do_sys_sendmsg(struct lwp *l, int s, struct msghdr *mp, int flags,
    530 		register_t *retsize)
    531 {
    532 	struct iovec	aiov[UIO_SMALLIOV], *iov = aiov, *tiov, *ktriov = NULL;
    533 	struct mbuf	*to, *control;
    534 	struct socket	*so;
    535 	struct uio	auio;
    536 	size_t		len, iovsz;
    537 	int		i, error;
    538 
    539 	ktrkuser("msghdr", mp, sizeof *mp);
    540 
    541 	/* If the caller passed us stuff in mbufs, we must free them. */
    542 	to = (mp->msg_flags & MSG_NAMEMBUF) ? mp->msg_name : NULL;
    543 	control = (mp->msg_flags & MSG_CONTROLMBUF) ? mp->msg_control : NULL;
    544 	iovsz = mp->msg_iovlen * sizeof(struct iovec);
    545 
    546 	if (mp->msg_flags & MSG_IOVUSRSPACE) {
    547 		if ((unsigned int)mp->msg_iovlen > UIO_SMALLIOV) {
    548 			if ((unsigned int)mp->msg_iovlen > IOV_MAX) {
    549 				error = EMSGSIZE;
    550 				goto bad;
    551 			}
    552 			iov = kmem_alloc(iovsz, KM_SLEEP);
    553 		}
    554 		if (mp->msg_iovlen != 0) {
    555 			error = copyin(mp->msg_iov, iov, iovsz);
    556 			if (error)
    557 				goto bad;
    558 		}
    559 		mp->msg_iov = iov;
    560 	}
    561 
    562 	auio.uio_iov = mp->msg_iov;
    563 	auio.uio_iovcnt = mp->msg_iovlen;
    564 	auio.uio_rw = UIO_WRITE;
    565 	auio.uio_offset = 0;			/* XXX */
    566 	auio.uio_resid = 0;
    567 	KASSERT(l == curlwp);
    568 	auio.uio_vmspace = l->l_proc->p_vmspace;
    569 
    570 	for (i = 0, tiov = mp->msg_iov; i < mp->msg_iovlen; i++, tiov++) {
    571 		/*
    572 		 * Writes return ssize_t because -1 is returned on error.
    573 		 * Therefore, we must restrict the length to SSIZE_MAX to
    574 		 * avoid garbage return values.
    575 		 */
    576 		auio.uio_resid += tiov->iov_len;
    577 		if (tiov->iov_len > SSIZE_MAX || auio.uio_resid > SSIZE_MAX) {
    578 			error = EINVAL;
    579 			goto bad;
    580 		}
    581 	}
    582 
    583 	if (mp->msg_name && to == NULL) {
    584 		error = sockargs(&to, mp->msg_name, mp->msg_namelen,
    585 		    MT_SONAME);
    586 		if (error)
    587 			goto bad;
    588 	}
    589 
    590 	if (mp->msg_control) {
    591 		if (mp->msg_controllen < CMSG_ALIGN(sizeof(struct cmsghdr))) {
    592 			error = EINVAL;
    593 			goto bad;
    594 		}
    595 		if (control == NULL) {
    596 			error = sockargs(&control, mp->msg_control,
    597 			    mp->msg_controllen, MT_CONTROL);
    598 			if (error)
    599 				goto bad;
    600 		}
    601 	}
    602 
    603 	if (ktrpoint(KTR_GENIO)) {
    604 		ktriov = kmem_alloc(iovsz, KM_SLEEP);
    605 		memcpy(ktriov, auio.uio_iov, iovsz);
    606 	}
    607 
    608 	if ((error = fd_getsock(s, &so)) != 0)
    609 		goto bad;
    610 
    611 	if (mp->msg_name)
    612 		MCLAIM(to, so->so_mowner);
    613 	if (mp->msg_control)
    614 		MCLAIM(control, so->so_mowner);
    615 
    616 	len = auio.uio_resid;
    617 	error = (*so->so_send)(so, to, &auio, NULL, control, flags, l);
    618 	/* Protocol is responsible for freeing 'control' */
    619 	control = NULL;
    620 
    621 	fd_putfile(s);
    622 
    623 	if (error) {
    624 		if (auio.uio_resid != len && (error == ERESTART ||
    625 		    error == EINTR || error == EWOULDBLOCK))
    626 			error = 0;
    627 		if (error == EPIPE && (flags & MSG_NOSIGNAL) == 0) {
    628 			mutex_enter(proc_lock);
    629 			psignal(l->l_proc, SIGPIPE);
    630 			mutex_exit(proc_lock);
    631 		}
    632 	}
    633 	if (error == 0)
    634 		*retsize = len - auio.uio_resid;
    635 
    636 bad:
    637 	if (ktriov != NULL) {
    638 		ktrgeniov(s, UIO_WRITE, ktriov, *retsize, error);
    639 		kmem_free(ktriov, iovsz);
    640 	}
    641 
    642  	if (iov != aiov)
    643  		kmem_free(iov, iovsz);
    644 	if (to)
    645 		m_freem(to);
    646 	if (control)
    647 		m_freem(control);
    648 
    649 	return (error);
    650 }
    651 
    652 int
    653 sys_recvfrom(struct lwp *l, const struct sys_recvfrom_args *uap, register_t *retval)
    654 {
    655 	/* {
    656 		syscallarg(int)			s;
    657 		syscallarg(void *)		buf;
    658 		syscallarg(size_t)		len;
    659 		syscallarg(int)			flags;
    660 		syscallarg(struct sockaddr *)	from;
    661 		syscallarg(unsigned int *)	fromlenaddr;
    662 	} */
    663 	struct msghdr	msg;
    664 	struct iovec	aiov;
    665 	int		error;
    666 	struct mbuf	*from;
    667 
    668 	msg.msg_name = NULL;
    669 	msg.msg_iov = &aiov;
    670 	msg.msg_iovlen = 1;
    671 	aiov.iov_base = SCARG(uap, buf);
    672 	aiov.iov_len = SCARG(uap, len);
    673 	msg.msg_control = NULL;
    674 	msg.msg_flags = SCARG(uap, flags) & MSG_USERFLAGS;
    675 
    676 	error = do_sys_recvmsg(l, SCARG(uap, s), &msg, &from, NULL, retval);
    677 	if (error != 0)
    678 		return error;
    679 
    680 	error = copyout_sockname(SCARG(uap, from), SCARG(uap, fromlenaddr),
    681 	    MSG_LENUSRSPACE, from);
    682 	if (from != NULL)
    683 		m_free(from);
    684 	return error;
    685 }
    686 
    687 int
    688 sys_recvmsg(struct lwp *l, const struct sys_recvmsg_args *uap, register_t *retval)
    689 {
    690 	/* {
    691 		syscallarg(int)			s;
    692 		syscallarg(struct msghdr *)	msg;
    693 		syscallarg(int)			flags;
    694 	} */
    695 	struct msghdr	msg;
    696 	int		error;
    697 	struct mbuf	*from, *control;
    698 
    699 	error = copyin(SCARG(uap, msg), &msg, sizeof(msg));
    700 	if (error)
    701 		return (error);
    702 
    703 	msg.msg_flags = (SCARG(uap, flags) & MSG_USERFLAGS) | MSG_IOVUSRSPACE;
    704 
    705 	error = do_sys_recvmsg(l, SCARG(uap, s), &msg, &from,
    706 	    msg.msg_control != NULL ? &control : NULL, retval);
    707 	if (error != 0)
    708 		return error;
    709 
    710 	if (msg.msg_control != NULL)
    711 		error = copyout_msg_control(l, &msg, control);
    712 
    713 	if (error == 0)
    714 		error = copyout_sockname(msg.msg_name, &msg.msg_namelen, 0,
    715 			from);
    716 	if (from != NULL)
    717 		m_free(from);
    718 	if (error == 0) {
    719 		ktrkuser("msghdr", &msg, sizeof msg);
    720 		error = copyout(&msg, SCARG(uap, msg), sizeof(msg));
    721 	}
    722 
    723 	return (error);
    724 }
    725 
    726 /*
    727  * Adjust for a truncated SCM_RIGHTS control message.
    728  *  This means closing any file descriptors that aren't present
    729  *  in the returned buffer.
    730  *  m is the mbuf holding the (already externalized) SCM_RIGHTS message.
    731  */
    732 static void
    733 free_rights(struct mbuf *m)
    734 {
    735 	int nfd;
    736 	int i;
    737 	int *fdv;
    738 
    739 	nfd = m->m_len < CMSG_SPACE(sizeof(int)) ? 0
    740 	    : (m->m_len - CMSG_SPACE(sizeof(int))) / sizeof(int) + 1;
    741 	fdv = (int *) CMSG_DATA(mtod(m,struct cmsghdr *));
    742 	for (i = 0; i < nfd; i++) {
    743 		if (fd_getfile(fdv[i]) != NULL)
    744 			(void)fd_close(fdv[i]);
    745 	}
    746 }
    747 
    748 void
    749 free_control_mbuf(struct lwp *l, struct mbuf *control, struct mbuf *uncopied)
    750 {
    751 	struct mbuf *next;
    752 	struct cmsghdr *cmsg;
    753 	bool do_free_rights = false;
    754 
    755 	while (control != NULL) {
    756 		cmsg = mtod(control, struct cmsghdr *);
    757 		if (control == uncopied)
    758 			do_free_rights = true;
    759 		if (do_free_rights && cmsg->cmsg_level == SOL_SOCKET
    760 		    && cmsg->cmsg_type == SCM_RIGHTS)
    761 			free_rights(control);
    762 		next = control->m_next;
    763 		m_free(control);
    764 		control = next;
    765 	}
    766 }
    767 
    768 /* Copy socket control/CMSG data to user buffer, frees the mbuf */
    769 int
    770 copyout_msg_control(struct lwp *l, struct msghdr *mp, struct mbuf *control)
    771 {
    772 	int i, len, error = 0;
    773 	struct cmsghdr *cmsg;
    774 	struct mbuf *m;
    775 	char *q;
    776 
    777 	len = mp->msg_controllen;
    778 	if (len <= 0 || control == 0) {
    779 		mp->msg_controllen = 0;
    780 		free_control_mbuf(l, control, control);
    781 		return 0;
    782 	}
    783 
    784 	q = (char *)mp->msg_control;
    785 
    786 	for (m = control; m != NULL; ) {
    787 		cmsg = mtod(m, struct cmsghdr *);
    788 		i = m->m_len;
    789 		if (len < i) {
    790 			mp->msg_flags |= MSG_CTRUNC;
    791 			if (cmsg->cmsg_level == SOL_SOCKET
    792 			    && cmsg->cmsg_type == SCM_RIGHTS)
    793 				/* Do not truncate me ... */
    794 				break;
    795 			i = len;
    796 		}
    797 		error = copyout(mtod(m, void *), q, i);
    798 		ktrkuser("msgcontrol", mtod(m, void *), i);
    799 		if (error != 0) {
    800 			/* We must free all the SCM_RIGHTS */
    801 			m = control;
    802 			break;
    803 		}
    804 		m = m->m_next;
    805 		if (m)
    806 			i = ALIGN(i);
    807 		q += i;
    808 		len -= i;
    809 		if (len <= 0)
    810 			break;
    811 	}
    812 
    813 	free_control_mbuf(l, control, m);
    814 
    815 	mp->msg_controllen = q - (char *)mp->msg_control;
    816 	return error;
    817 }
    818 
    819 int
    820 do_sys_recvmsg(struct lwp *l, int s, struct msghdr *mp, struct mbuf **from,
    821     struct mbuf **control, register_t *retsize)
    822 {
    823 	struct iovec	aiov[UIO_SMALLIOV], *iov = aiov, *tiov, *ktriov;
    824 	struct socket	*so;
    825 	struct uio	auio;
    826 	size_t		len, iovsz;
    827 	int		i, error;
    828 
    829 	ktrkuser("msghdr", mp, sizeof *mp);
    830 
    831 	*from = NULL;
    832 	if (control != NULL)
    833 		*control = NULL;
    834 
    835 	if ((error = fd_getsock(s, &so)) != 0)
    836 		return (error);
    837 
    838 	iovsz = mp->msg_iovlen * sizeof(struct iovec);
    839 
    840 	if (mp->msg_flags & MSG_IOVUSRSPACE) {
    841 		if ((unsigned int)mp->msg_iovlen > UIO_SMALLIOV) {
    842 			if ((unsigned int)mp->msg_iovlen > IOV_MAX) {
    843 				error = EMSGSIZE;
    844 				goto out;
    845 			}
    846 			iov = kmem_alloc(iovsz, KM_SLEEP);
    847 		}
    848 		if (mp->msg_iovlen != 0) {
    849 			error = copyin(mp->msg_iov, iov, iovsz);
    850 			if (error)
    851 				goto out;
    852 		}
    853 		auio.uio_iov = iov;
    854 	} else
    855 		auio.uio_iov = mp->msg_iov;
    856 	auio.uio_iovcnt = mp->msg_iovlen;
    857 	auio.uio_rw = UIO_READ;
    858 	auio.uio_offset = 0;			/* XXX */
    859 	auio.uio_resid = 0;
    860 	KASSERT(l == curlwp);
    861 	auio.uio_vmspace = l->l_proc->p_vmspace;
    862 
    863 	tiov = auio.uio_iov;
    864 	for (i = 0; i < mp->msg_iovlen; i++, tiov++) {
    865 		/*
    866 		 * Reads return ssize_t because -1 is returned on error.
    867 		 * Therefore we must restrict the length to SSIZE_MAX to
    868 		 * avoid garbage return values.
    869 		 */
    870 		auio.uio_resid += tiov->iov_len;
    871 		if (tiov->iov_len > SSIZE_MAX || auio.uio_resid > SSIZE_MAX) {
    872 			error = EINVAL;
    873 			goto out;
    874 		}
    875 	}
    876 
    877 	ktriov = NULL;
    878 	if (ktrpoint(KTR_GENIO)) {
    879 		ktriov = kmem_alloc(iovsz, KM_SLEEP);
    880 		memcpy(ktriov, auio.uio_iov, iovsz);
    881 	}
    882 
    883 	len = auio.uio_resid;
    884 	mp->msg_flags &= MSG_USERFLAGS;
    885 	error = (*so->so_receive)(so, from, &auio, NULL, control,
    886 	    &mp->msg_flags);
    887 	len -= auio.uio_resid;
    888 	*retsize = len;
    889 	if (error != 0 && len != 0
    890 	    && (error == ERESTART || error == EINTR || error == EWOULDBLOCK))
    891 		/* Some data transferred */
    892 		error = 0;
    893 
    894 	if (ktriov != NULL) {
    895 		ktrgeniov(s, UIO_READ, ktriov, len, error);
    896 		kmem_free(ktriov, iovsz);
    897 	}
    898 
    899 	if (error != 0) {
    900 		m_freem(*from);
    901 		*from = NULL;
    902 		if (control != NULL) {
    903 			free_control_mbuf(l, *control, *control);
    904 			*control = NULL;
    905 		}
    906 	}
    907  out:
    908 	if (iov != aiov)
    909 		kmem_free(iov, iovsz);
    910 	fd_putfile(s);
    911 	return (error);
    912 }
    913 
    914 
    915 /* ARGSUSED */
    916 int
    917 sys_shutdown(struct lwp *l, const struct sys_shutdown_args *uap, register_t *retval)
    918 {
    919 	/* {
    920 		syscallarg(int)	s;
    921 		syscallarg(int)	how;
    922 	} */
    923 	struct socket	*so;
    924 	int		error;
    925 
    926 	if ((error = fd_getsock(SCARG(uap, s), &so)) != 0)
    927 		return (error);
    928 	solock(so);
    929 	error = soshutdown(so, SCARG(uap, how));
    930 	sounlock(so);
    931 	fd_putfile(SCARG(uap, s));
    932 	return (error);
    933 }
    934 
    935 /* ARGSUSED */
    936 int
    937 sys_setsockopt(struct lwp *l, const struct sys_setsockopt_args *uap, register_t *retval)
    938 {
    939 	/* {
    940 		syscallarg(int)			s;
    941 		syscallarg(int)			level;
    942 		syscallarg(int)			name;
    943 		syscallarg(const void *)	val;
    944 		syscallarg(unsigned int)	valsize;
    945 	} */
    946 	struct sockopt	sopt;
    947 	struct socket	*so;
    948 	int		error;
    949 	unsigned int	len;
    950 
    951 	len = SCARG(uap, valsize);
    952 	if (len > 0 && SCARG(uap, val) == NULL)
    953 		return (EINVAL);
    954 
    955 	if (len > MCLBYTES)
    956 		return (EINVAL);
    957 
    958 	if ((error = fd_getsock(SCARG(uap, s), &so)) != 0)
    959 		return (error);
    960 
    961 	sockopt_init(&sopt, SCARG(uap, level), SCARG(uap, name), len);
    962 
    963 	if (len > 0) {
    964 		error = copyin(SCARG(uap, val), sopt.sopt_data, len);
    965 		if (error)
    966 			goto out;
    967 	}
    968 
    969 	error = sosetopt(so, &sopt);
    970 
    971  out:
    972 	sockopt_destroy(&sopt);
    973  	fd_putfile(SCARG(uap, s));
    974 	return (error);
    975 }
    976 
    977 /* ARGSUSED */
    978 int
    979 sys_getsockopt(struct lwp *l, const struct sys_getsockopt_args *uap, register_t *retval)
    980 {
    981 	/* {
    982 		syscallarg(int)			s;
    983 		syscallarg(int)			level;
    984 		syscallarg(int)			name;
    985 		syscallarg(void *)		val;
    986 		syscallarg(unsigned int *)	avalsize;
    987 	} */
    988 	struct sockopt	sopt;
    989 	struct socket	*so;
    990 	unsigned int	valsize, len;
    991 	int		error;
    992 
    993 	if (SCARG(uap, val) != NULL) {
    994 		error = copyin(SCARG(uap, avalsize), &valsize, sizeof(valsize));
    995 		if (error)
    996 			return (error);
    997 	} else
    998 		valsize = 0;
    999 
   1000 	if ((error = fd_getsock(SCARG(uap, s), &so)) != 0)
   1001 		return (error);
   1002 
   1003 	sockopt_init(&sopt, SCARG(uap, level), SCARG(uap, name), 0);
   1004 
   1005 	error = sogetopt(so, &sopt);
   1006 	if (error)
   1007 		goto out;
   1008 
   1009 	if (valsize > 0) {
   1010 		len = min(valsize, sopt.sopt_size);
   1011 		error = copyout(sopt.sopt_data, SCARG(uap, val), len);
   1012 		if (error)
   1013 			goto out;
   1014 
   1015 		error = copyout(&len, SCARG(uap, avalsize), sizeof(len));
   1016 		if (error)
   1017 			goto out;
   1018 	}
   1019 
   1020  out:
   1021 	sockopt_destroy(&sopt);
   1022  	fd_putfile(SCARG(uap, s));
   1023 	return (error);
   1024 }
   1025 
   1026 #ifdef PIPE_SOCKETPAIR
   1027 /* ARGSUSED */
   1028 int
   1029 pipe1(struct lwp *l, register_t *retval, int flags)
   1030 {
   1031 	file_t		*rf, *wf;
   1032 	struct socket	*rso, *wso;
   1033 	int		fd, error;
   1034 	proc_t		*p;
   1035 
   1036 	if (flags & ~(O_CLOEXEC|O_NONBLOCK))
   1037 		return EINVAL;
   1038 	p = curproc;
   1039 	if ((error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0, l, NULL)) != 0)
   1040 		return (error);
   1041 	if ((error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0, l, rso)) != 0)
   1042 		goto free1;
   1043 	/* remember this socket pair implements a pipe */
   1044 	wso->so_state |= SS_ISAPIPE;
   1045 	rso->so_state |= SS_ISAPIPE;
   1046 	if ((error = fd_allocfile(&rf, &fd)) != 0)
   1047 		goto free2;
   1048 	retval[0] = fd;
   1049 	rf->f_flag = FREAD | flags;
   1050 	rf->f_type = DTYPE_SOCKET;
   1051 	rf->f_ops = &socketops;
   1052 	rf->f_data = rso;
   1053 	if ((error = fd_allocfile(&wf, &fd)) != 0)
   1054 		goto free3;
   1055 	wf->f_flag = FWRITE | flags;
   1056 	wf->f_type = DTYPE_SOCKET;
   1057 	wf->f_ops = &socketops;
   1058 	wf->f_data = wso;
   1059 	retval[1] = fd;
   1060 	solock(wso);
   1061 	error = unp_connect2(wso, rso, PRU_CONNECT2);
   1062 	sounlock(wso);
   1063 	if (error != 0)
   1064 		goto free4;
   1065 	fd_affix(p, wf, (int)retval[1]);
   1066 	fd_affix(p, rf, (int)retval[0]);
   1067 	return (0);
   1068  free4:
   1069 	fd_abort(p, wf, (int)retval[1]);
   1070  free3:
   1071 	fd_abort(p, rf, (int)retval[0]);
   1072  free2:
   1073 	(void)soclose(wso);
   1074  free1:
   1075 	(void)soclose(rso);
   1076 	return (error);
   1077 }
   1078 #endif /* PIPE_SOCKETPAIR */
   1079 
   1080 /*
   1081  * Get socket name.
   1082  */
   1083 /* ARGSUSED */
   1084 int
   1085 do_sys_getsockname(struct lwp *l, int fd, int which, struct mbuf **nam)
   1086 {
   1087 	struct socket	*so;
   1088 	struct mbuf	*m;
   1089 	int		error;
   1090 
   1091 	if ((error = fd_getsock(fd, &so)) != 0)
   1092 		return error;
   1093 
   1094 	m = m_getclr(M_WAIT, MT_SONAME);
   1095 	MCLAIM(m, so->so_mowner);
   1096 
   1097 	solock(so);
   1098 	if (which == PRU_PEERADDR
   1099 	    && (so->so_state & (SS_ISCONNECTED | SS_ISCONFIRMING)) == 0) {
   1100 		error = ENOTCONN;
   1101 	} else {
   1102 		*nam = m;
   1103 		error = (*so->so_proto->pr_usrreq)(so, which, NULL, m, NULL,
   1104 		    NULL);
   1105 	}
   1106  	sounlock(so);
   1107 	if (error != 0)
   1108 		m_free(m);
   1109  	fd_putfile(fd);
   1110 	return error;
   1111 }
   1112 
   1113 int
   1114 copyout_sockname(struct sockaddr *asa, unsigned int *alen, int flags,
   1115     struct mbuf *addr)
   1116 {
   1117 	int len;
   1118 	int error;
   1119 
   1120 	if (asa == NULL)
   1121 		/* Assume application not interested */
   1122 		return 0;
   1123 
   1124 	if (flags & MSG_LENUSRSPACE) {
   1125 		error = copyin(alen, &len, sizeof(len));
   1126 		if (error)
   1127 			return error;
   1128 	} else
   1129 		len = *alen;
   1130 	if (len < 0)
   1131 		return EINVAL;
   1132 
   1133 	if (addr == NULL) {
   1134 		len = 0;
   1135 		error = 0;
   1136 	} else {
   1137 		if (len > addr->m_len)
   1138 			len = addr->m_len;
   1139 		/* Maybe this ought to copy a chain ? */
   1140 		ktrkuser("sockname", mtod(addr, void *), len);
   1141 		error = copyout(mtod(addr, void *), asa, len);
   1142 	}
   1143 
   1144 	if (error == 0) {
   1145 		if (flags & MSG_LENUSRSPACE)
   1146 			error = copyout(&len, alen, sizeof(len));
   1147 		else
   1148 			*alen = len;
   1149 	}
   1150 
   1151 	return error;
   1152 }
   1153 
   1154 /*
   1155  * Get socket name.
   1156  */
   1157 /* ARGSUSED */
   1158 int
   1159 sys_getsockname(struct lwp *l, const struct sys_getsockname_args *uap, register_t *retval)
   1160 {
   1161 	/* {
   1162 		syscallarg(int)			fdes;
   1163 		syscallarg(struct sockaddr *)	asa;
   1164 		syscallarg(unsigned int *)	alen;
   1165 	} */
   1166 	struct mbuf	*m;
   1167 	int		error;
   1168 
   1169 	error = do_sys_getsockname(l, SCARG(uap, fdes), PRU_SOCKADDR, &m);
   1170 	if (error != 0)
   1171 		return error;
   1172 
   1173 	error = copyout_sockname(SCARG(uap, asa), SCARG(uap, alen),
   1174 	    MSG_LENUSRSPACE, m);
   1175 	if (m != NULL)
   1176 		m_free(m);
   1177 	return error;
   1178 }
   1179 
   1180 /*
   1181  * Get name of peer for connected socket.
   1182  */
   1183 /* ARGSUSED */
   1184 int
   1185 sys_getpeername(struct lwp *l, const struct sys_getpeername_args *uap, register_t *retval)
   1186 {
   1187 	/* {
   1188 		syscallarg(int)			fdes;
   1189 		syscallarg(struct sockaddr *)	asa;
   1190 		syscallarg(unsigned int *)	alen;
   1191 	} */
   1192 	struct mbuf	*m;
   1193 	int		error;
   1194 
   1195 	error = do_sys_getsockname(l, SCARG(uap, fdes), PRU_PEERADDR, &m);
   1196 	if (error != 0)
   1197 		return error;
   1198 
   1199 	error = copyout_sockname(SCARG(uap, asa), SCARG(uap, alen),
   1200 	    MSG_LENUSRSPACE, m);
   1201 	if (m != NULL)
   1202 		m_free(m);
   1203 	return error;
   1204 }
   1205 
   1206 /*
   1207  * XXX In a perfect world, we wouldn't pass around socket control
   1208  * XXX arguments in mbufs, and this could go away.
   1209  */
   1210 int
   1211 sockargs(struct mbuf **mp, const void *bf, size_t buflen, int type)
   1212 {
   1213 	struct sockaddr	*sa;
   1214 	struct mbuf	*m;
   1215 	int		error;
   1216 
   1217 	/*
   1218 	 * We can't allow socket names > UCHAR_MAX in length, since that
   1219 	 * will overflow sa_len.  Control data more than a page size in
   1220 	 * length is just too much.
   1221 	 */
   1222 	if (buflen > (type == MT_SONAME ? UCHAR_MAX : PAGE_SIZE))
   1223 		return (EINVAL);
   1224 
   1225 	/* Allocate an mbuf to hold the arguments. */
   1226 	m = m_get(M_WAIT, type);
   1227 	/* can't claim.  don't who to assign it to. */
   1228 	if (buflen > MLEN) {
   1229 		/*
   1230 		 * Won't fit into a regular mbuf, so we allocate just
   1231 		 * enough external storage to hold the argument.
   1232 		 */
   1233 		MEXTMALLOC(m, buflen, M_WAITOK);
   1234 	}
   1235 	m->m_len = buflen;
   1236 	error = copyin(bf, mtod(m, void *), buflen);
   1237 	if (error) {
   1238 		(void) m_free(m);
   1239 		return (error);
   1240 	}
   1241 	ktrkuser(mbuftypes[type], mtod(m, void *), buflen);
   1242 	*mp = m;
   1243 	if (type == MT_SONAME) {
   1244 		sa = mtod(m, struct sockaddr *);
   1245 #if BYTE_ORDER != BIG_ENDIAN
   1246 		/*
   1247 		 * 4.3BSD compat thing - need to stay, since bind(2),
   1248 		 * connect(2), sendto(2) were not versioned for COMPAT_43.
   1249 		 */
   1250 		if (sa->sa_family == 0 && sa->sa_len < AF_MAX)
   1251 			sa->sa_family = sa->sa_len;
   1252 #endif
   1253 		sa->sa_len = buflen;
   1254 	}
   1255 	return (0);
   1256 }
   1257