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NetBSD/sys/kern/uipc_socket.c

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/* $NetBSD: uipc_socket.c,v 1.71 2002/08/21 05:13:37 thorpej Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of Wasabi Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1982, 1986, 1988, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)uipc_socket.c 8.6 (Berkeley) 5/2/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.71 2002/08/21 05:13:37 thorpej Exp $");
#include "opt_sock_counters.h"
#include "opt_sosend_loan.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/kernel.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/resourcevar.h>
#include <sys/pool.h>
#include <uvm/uvm.h>
struct pool socket_pool;
extern int somaxconn; /* patchable (XXX sysctl) */
int somaxconn = SOMAXCONN;
#ifdef SOSEND_COUNTERS
#include <sys/device.h>
struct evcnt sosend_loan_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "loan big");
struct evcnt sosend_copy_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "copy big");
struct evcnt sosend_copy_small = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "copy small");
struct evcnt sosend_kvalimit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "kva limit");
#define SOSEND_COUNTER_INCR(ev) (ev)->ev_count++
#else
#define SOSEND_COUNTER_INCR(ev) /* nothing */
#endif /* SOSEND_COUNTERS */
void
soinit(void)
{
pool_init(&socket_pool, sizeof(struct socket), 0, 0, 0,
"sockpl", NULL);
#ifdef SOSEND_COUNTERS
evcnt_attach_static(&sosend_loan_big);
evcnt_attach_static(&sosend_copy_big);
evcnt_attach_static(&sosend_copy_small);
evcnt_attach_static(&sosend_kvalimit);
#endif /* SOSEND_COUNTERS */
}
#ifdef SOSEND_NO_LOAN
int use_sosend_loan = 0;
#else
int use_sosend_loan = 1;
#endif
struct mbuf *so_pendfree;
int somaxkva = 16 * 1024 * 1024;
int socurkva;
int sokvawaiters;
#define SOCK_LOAN_THRESH 4096
#define SOCK_LOAN_CHUNK 65536
static void
sodoloanfree(caddr_t buf, u_int size)
{
struct vm_page **pgs;
vaddr_t va, sva, eva;
vsize_t len;
paddr_t pa;
int i, npgs;
eva = round_page((vaddr_t) buf + size);
sva = trunc_page((vaddr_t) buf);
len = eva - sva;
npgs = len >> PAGE_SHIFT;
pgs = alloca(npgs * sizeof(*pgs));
for (i = 0, va = sva; va < eva; i++, va += PAGE_SIZE) {
if (pmap_extract(pmap_kernel(), va, &pa) == FALSE)
panic("sodoloanfree: va 0x%lx not mapped", va);
pgs[i] = PHYS_TO_VM_PAGE(pa);
}
pmap_kremove(sva, len);
pmap_update(pmap_kernel());
uvm_unloan(pgs, npgs, UVM_LOAN_TOPAGE);
uvm_km_free(kernel_map, sva, len);
socurkva -= len;
if (sokvawaiters)
wakeup(&socurkva);
}
static size_t
sodopendfree(struct socket *so)
{
struct mbuf *m;
size_t rv = 0;
int s;
s = splvm();
for (;;) {
m = so_pendfree;
if (m == NULL)
break;
so_pendfree = m->m_next;
splx(s);
rv += m->m_ext.ext_size;
sodoloanfree(m->m_ext.ext_buf, m->m_ext.ext_size);
s = splvm();
pool_cache_put(&mbpool_cache, m);
}
for (;;) {
m = so->so_pendfree;
if (m == NULL)
break;
so->so_pendfree = m->m_next;
splx(s);
rv += m->m_ext.ext_size;
sodoloanfree(m->m_ext.ext_buf, m->m_ext.ext_size);
s = splvm();
pool_cache_put(&mbpool_cache, m);
}
splx(s);
return (rv);
}
static void
soloanfree(struct mbuf *m, caddr_t buf, u_int size, void *arg)
{
struct socket *so = arg;
int s;
if (m == NULL) {
sodoloanfree(buf, size);
return;
}
s = splvm();
m->m_next = so->so_pendfree;
so->so_pendfree = m;
splx(s);
if (sokvawaiters)
wakeup(&socurkva);
}
static long
sosend_loan(struct socket *so, struct uio *uio, struct mbuf *m, long space)
{
struct iovec *iov = uio->uio_iov;
vaddr_t sva, eva;
vsize_t len;
struct vm_page **pgs;
vaddr_t lva, va;
int npgs, s, i, error;
if (uio->uio_segflg != UIO_USERSPACE)
return (0);
if (iov->iov_len < (size_t) space)
space = iov->iov_len;
if (space > SOCK_LOAN_CHUNK)
space = SOCK_LOAN_CHUNK;
eva = round_page((vaddr_t) iov->iov_base + space);
sva = trunc_page((vaddr_t) iov->iov_base);
len = eva - sva;
npgs = len >> PAGE_SHIFT;
while (socurkva + len > somaxkva) {
if (sodopendfree(so))
continue;
SOSEND_COUNTER_INCR(&sosend_kvalimit);
s = splvm();
sokvawaiters++;
(void) tsleep(&socurkva, PVM, "sokva", 0);
sokvawaiters--;
splx(s);
}
lva = uvm_km_valloc_wait(kernel_map, len);
if (lva == 0)
return (0);
socurkva += len;
pgs = alloca(npgs * sizeof(*pgs));
error = uvm_loan(&uio->uio_procp->p_vmspace->vm_map, sva, len,
pgs, UVM_LOAN_TOPAGE);
if (error) {
uvm_km_free(kernel_map, lva, len);
socurkva -= len;
return (0);
}
for (i = 0, va = lva; i < npgs; i++, va += PAGE_SIZE)
pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pgs[i]), VM_PROT_READ);
pmap_update(pmap_kernel());
lva += (vaddr_t) iov->iov_base & PAGE_MASK;
MEXTADD(m, (caddr_t) lva, space, M_MBUF, soloanfree, so);
uio->uio_resid -= space;
/* uio_offset not updated, not set/used for write(2) */
uio->uio_iov->iov_base = (caddr_t) uio->uio_iov->iov_base + space;
uio->uio_iov->iov_len -= space;
if (uio->uio_iov->iov_len == 0) {
uio->uio_iov++;
uio->uio_iovcnt--;
}
return (space);
}
/*
* Socket operation routines.
* These routines are called by the routines in
* sys_socket.c or from a system process, and
* implement the semantics of socket operations by
* switching out to the protocol specific routines.
*/
/*ARGSUSED*/
int
socreate(int dom, struct socket **aso, int type, int proto)
{
struct proc *p;
struct protosw *prp;
struct socket *so;
int error, s;
p = curproc; /* XXX */
if (proto)
prp = pffindproto(dom, proto, type);
else
prp = pffindtype(dom, type);
if (prp == 0 || prp->pr_usrreq == 0)
return (EPROTONOSUPPORT);
if (prp->pr_type != type)
return (EPROTOTYPE);
s = splsoftnet();
so = pool_get(&socket_pool, PR_WAITOK);
memset((caddr_t)so, 0, sizeof(*so));
TAILQ_INIT(&so->so_q0);
TAILQ_INIT(&so->so_q);
so->so_type = type;
so->so_proto = prp;
so->so_send = sosend;
so->so_receive = soreceive;
if (p != 0)
so->so_uid = p->p_ucred->cr_uid;
error = (*prp->pr_usrreq)(so, PRU_ATTACH, (struct mbuf *)0,
(struct mbuf *)(long)proto, (struct mbuf *)0, p);
if (error) {
so->so_state |= SS_NOFDREF;
sofree(so);
splx(s);
return (error);
}
splx(s);
*aso = so;
return (0);
}
int
sobind(struct socket *so, struct mbuf *nam, struct proc *p)
{
int s, error;
s = splsoftnet();
error = (*so->so_proto->pr_usrreq)(so, PRU_BIND, (struct mbuf *)0,
nam, (struct mbuf *)0, p);
splx(s);
return (error);
}
int
solisten(struct socket *so, int backlog)
{
int s, error;
s = splsoftnet();
error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, (struct mbuf *)0,
(struct mbuf *)0, (struct mbuf *)0, (struct proc *)0);
if (error) {
splx(s);
return (error);
}
if (TAILQ_EMPTY(&so->so_q))
so->so_options |= SO_ACCEPTCONN;
if (backlog < 0)
backlog = 0;
so->so_qlimit = min(backlog, somaxconn);
splx(s);
return (0);
}
void
sofree(struct socket *so)
{
struct mbuf *m;
if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0)
return;
if (so->so_head) {
/*
* We must not decommission a socket that's on the accept(2)
* queue. If we do, then accept(2) may hang after select(2)
* indicated that the listening socket was ready.
*/
if (!soqremque(so, 0))
return;
}
sbrelease(&so->so_snd);
sorflush(so);
while ((m = so->so_pendfree) != NULL) {
so->so_pendfree = m->m_next;
m->m_next = so_pendfree;
so_pendfree = m;
}
pool_put(&socket_pool, so);
}
/*
* Close a socket on last file table reference removal.
* Initiate disconnect if connected.
* Free socket when disconnect complete.
*/
int
soclose(struct socket *so)
{
struct socket *so2;
int s, error;
error = 0;
s = splsoftnet(); /* conservative */
if (so->so_options & SO_ACCEPTCONN) {
while ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) {
(void) soqremque(so2, 0);
(void) soabort(so2);
}
while ((so2 = TAILQ_FIRST(&so->so_q)) != 0) {
(void) soqremque(so2, 1);
(void) soabort(so2);
}
}
if (so->so_pcb == 0)
goto discard;
if (so->so_state & SS_ISCONNECTED) {
if ((so->so_state & SS_ISDISCONNECTING) == 0) {
error = sodisconnect(so);
if (error)
goto drop;
}
if (so->so_options & SO_LINGER) {
if ((so->so_state & SS_ISDISCONNECTING) &&
(so->so_state & SS_NBIO))
goto drop;
while (so->so_state & SS_ISCONNECTED) {
error = tsleep((caddr_t)&so->so_timeo,
PSOCK | PCATCH, netcls,
so->so_linger * hz);
if (error)
break;
}
}
}
drop:
if (so->so_pcb) {
int error2 = (*so->so_proto->pr_usrreq)(so, PRU_DETACH,
(struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0,
(struct proc *)0);
if (error == 0)
error = error2;
}
discard:
if (so->so_state & SS_NOFDREF)
panic("soclose: NOFDREF");
so->so_state |= SS_NOFDREF;
sofree(so);
splx(s);
return (error);
}
/*
* Must be called at splsoftnet...
*/
int
soabort(struct socket *so)
{
return (*so->so_proto->pr_usrreq)(so, PRU_ABORT, (struct mbuf *)0,
(struct mbuf *)0, (struct mbuf *)0, (struct proc *)0);
}
int
soaccept(struct socket *so, struct mbuf *nam)
{
int s, error;
error = 0;
s = splsoftnet();
if ((so->so_state & SS_NOFDREF) == 0)
panic("soaccept: !NOFDREF");
so->so_state &= ~SS_NOFDREF;
if ((so->so_state & SS_ISDISCONNECTED) == 0 ||
(so->so_proto->pr_flags & PR_ABRTACPTDIS) == 0)
error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT,
(struct mbuf *)0, nam, (struct mbuf *)0, (struct proc *)0);
else
error = ECONNABORTED;
splx(s);
return (error);
}
int
soconnect(struct socket *so, struct mbuf *nam)
{
struct proc *p;
int s, error;
p = curproc; /* XXX */
if (so->so_options & SO_ACCEPTCONN)
return (EOPNOTSUPP);
s = splsoftnet();
/*
* If protocol is connection-based, can only connect once.
* Otherwise, if connected, try to disconnect first.
* This allows user to disconnect by connecting to, e.g.,
* a null address.
*/
if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
(error = sodisconnect(so))))
error = EISCONN;
else
error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT,
(struct mbuf *)0, nam, (struct mbuf *)0, p);
splx(s);
return (error);
}
int
soconnect2(struct socket *so1, struct socket *so2)
{
int s, error;
s = splsoftnet();
error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2,
(struct mbuf *)0, (struct mbuf *)so2, (struct mbuf *)0,
(struct proc *)0);
splx(s);
return (error);
}
int
sodisconnect(struct socket *so)
{
int s, error;
s = splsoftnet();
if ((so->so_state & SS_ISCONNECTED) == 0) {
error = ENOTCONN;
goto bad;
}
if (so->so_state & SS_ISDISCONNECTING) {
error = EALREADY;
goto bad;
}
error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT,
(struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0,
(struct proc *)0);
bad:
splx(s);
sodopendfree(so);
return (error);
}
#define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
/*
* Send on a socket.
* If send must go all at once and message is larger than
* send buffering, then hard error.
* Lock against other senders.
* If must go all at once and not enough room now, then
* inform user that this would block and do nothing.
* Otherwise, if nonblocking, send as much as possible.
* The data to be sent is described by "uio" if nonzero,
* otherwise by the mbuf chain "top" (which must be null
* if uio is not). Data provided in mbuf chain must be small
* enough to send all at once.
*
* Returns nonzero on error, timeout or signal; callers
* must check for short counts if EINTR/ERESTART are returned.
* Data and control buffers are freed on return.
*/
int
sosend(struct socket *so, struct mbuf *addr, struct uio *uio, struct mbuf *top,
struct mbuf *control, int flags)
{
struct proc *p;
struct mbuf **mp, *m;
long space, len, resid, clen, mlen;
int error, s, dontroute, atomic;
sodopendfree(so);
p = curproc; /* XXX */
clen = 0;
atomic = sosendallatonce(so) || top;
if (uio)
resid = uio->uio_resid;
else
resid = top->m_pkthdr.len;
/*
* In theory resid should be unsigned.
* However, space must be signed, as it might be less than 0
* if we over-committed, and we must use a signed comparison
* of space and resid. On the other hand, a negative resid
* causes us to loop sending 0-length segments to the protocol.
*/
if (resid < 0) {
error = EINVAL;
goto out;
}
dontroute =
(flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
(so->so_proto->pr_flags & PR_ATOMIC);
p->p_stats->p_ru.ru_msgsnd++;
if (control)
clen = control->m_len;
#define snderr(errno) { error = errno; splx(s); goto release; }
restart:
if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0)
goto out;
do {
s = splsoftnet();
if (so->so_state & SS_CANTSENDMORE)
snderr(EPIPE);
if (so->so_error) {
error = so->so_error;
so->so_error = 0;
splx(s);
goto release;
}
if ((so->so_state & SS_ISCONNECTED) == 0) {
if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
if ((so->so_state & SS_ISCONFIRMING) == 0 &&
!(resid == 0 && clen != 0))
snderr(ENOTCONN);
} else if (addr == 0)
snderr(EDESTADDRREQ);
}
space = sbspace(&so->so_snd);
if (flags & MSG_OOB)
space += 1024;
if ((atomic && resid > so->so_snd.sb_hiwat) ||
clen > so->so_snd.sb_hiwat)
snderr(EMSGSIZE);
if (space < resid + clen && uio &&
(atomic || space < so->so_snd.sb_lowat || space < clen)) {
if (so->so_state & SS_NBIO)
snderr(EWOULDBLOCK);
sbunlock(&so->so_snd);
error = sbwait(&so->so_snd);
splx(s);
if (error)
goto out;
goto restart;
}
splx(s);
mp = &top;
space -= clen;
do {
if (uio == NULL) {
/*
* Data is prepackaged in "top".
*/
resid = 0;
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
} else do {
if (top == 0) {
MGETHDR(m, M_WAIT, MT_DATA);
mlen = MHLEN;
m->m_pkthdr.len = 0;
m->m_pkthdr.rcvif = (struct ifnet *)0;
} else {
MGET(m, M_WAIT, MT_DATA);
mlen = MLEN;
}
if (use_sosend_loan &&
uio->uio_iov->iov_len >= SOCK_LOAN_THRESH &&
space >= SOCK_LOAN_THRESH &&
(len = sosend_loan(so, uio, m,
space)) != 0) {
SOSEND_COUNTER_INCR(&sosend_loan_big);
space -= len;
goto have_data;
}
if (resid >= MINCLSIZE && space >= MCLBYTES) {
SOSEND_COUNTER_INCR(&sosend_copy_big);
MCLGET(m, M_WAIT);
if ((m->m_flags & M_EXT) == 0)
goto nopages;
mlen = MCLBYTES;
if (atomic && top == 0) {
len = lmin(MCLBYTES - max_hdr,
resid);
m->m_data += max_hdr;
} else
len = lmin(MCLBYTES, resid);
space -= len;
} else {
nopages:
SOSEND_COUNTER_INCR(&sosend_copy_small);
len = lmin(lmin(mlen, resid), space);
space -= len;
/*
* For datagram protocols, leave room
* for protocol headers in first mbuf.
*/
if (atomic && top == 0 && len < mlen)
MH_ALIGN(m, len);
}
error = uiomove(mtod(m, caddr_t), (int)len,
uio);
have_data:
resid = uio->uio_resid;
m->m_len = len;
*mp = m;
top->m_pkthdr.len += len;
if (error)
goto release;
mp = &m->m_next;
if (resid <= 0) {
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
break;
}
} while (space > 0 && atomic);
s = splsoftnet();
if (so->so_state & SS_CANTSENDMORE)
snderr(EPIPE);
if (dontroute)
so->so_options |= SO_DONTROUTE;
if (resid > 0)
so->so_state |= SS_MORETOCOME;
error = (*so->so_proto->pr_usrreq)(so,
(flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND,
top, addr, control, p);
if (dontroute)
so->so_options &= ~SO_DONTROUTE;
if (resid > 0)
so->so_state &= ~SS_MORETOCOME;
splx(s);
clen = 0;
control = 0;
top = 0;
mp = &top;
if (error)
goto release;
} while (resid && space > 0);
} while (resid);
release:
sbunlock(&so->so_snd);
out:
if (top)
m_freem(top);
if (control)
m_freem(control);
return (error);
}
/*
* Implement receive operations on a socket.
* We depend on the way that records are added to the sockbuf
* by sbappend*. In particular, each record (mbufs linked through m_next)
* must begin with an address if the protocol so specifies,
* followed by an optional mbuf or mbufs containing ancillary data,
* and then zero or more mbufs of data.
* In order to avoid blocking network interrupts for the entire time here,
* we splx() while doing the actual copy to user space.
* Although the sockbuf is locked, new data may still be appended,
* and thus we must maintain consistency of the sockbuf during that time.
*
* The caller may receive the data as a single mbuf chain by supplying
* an mbuf **mp0 for use in returning the chain. The uio is then used
* only for the count in uio_resid.
*/
int
soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio,
struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
{
struct mbuf *m, **mp;
int flags, len, error, s, offset, moff, type, orig_resid;
struct protosw *pr;
struct mbuf *nextrecord;
int mbuf_removed = 0;
pr = so->so_proto;
mp = mp0;
type = 0;
orig_resid = uio->uio_resid;
if (paddr)
*paddr = 0;
if (controlp)
*controlp = 0;
if (flagsp)
flags = *flagsp &~ MSG_EOR;
else
flags = 0;
if ((flags & MSG_DONTWAIT) == 0)
sodopendfree(so);
if (flags & MSG_OOB) {
m = m_get(M_WAIT, MT_DATA);
error = (*pr->pr_usrreq)(so, PRU_RCVOOB, m,
(struct mbuf *)(long)(flags & MSG_PEEK), (struct mbuf *)0,
(struct proc *)0);
if (error)
goto bad;
do {
error = uiomove(mtod(m, caddr_t),
(int) min(uio->uio_resid, m->m_len), uio);
m = m_free(m);
} while (uio->uio_resid && error == 0 && m);
bad:
if (m)
m_freem(m);
return (error);
}
if (mp)
*mp = (struct mbuf *)0;
if (so->so_state & SS_ISCONFIRMING && uio->uio_resid)
(*pr->pr_usrreq)(so, PRU_RCVD, (struct mbuf *)0,
(struct mbuf *)0, (struct mbuf *)0, (struct proc *)0);
restart:
if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0)
return (error);
s = splsoftnet();
m = so->so_rcv.sb_mb;
/*
* If we have less data than requested, block awaiting more
* (subject to any timeout) if:
* 1. the current count is less than the low water mark,
* 2. MSG_WAITALL is set, and it is possible to do the entire
* receive operation at once if we block (resid <= hiwat), or
* 3. MSG_DONTWAIT is not set.
* If MSG_WAITALL is set but resid is larger than the receive buffer,
* we have to do the receive in sections, and thus risk returning
* a short count if a timeout or signal occurs after we start.
*/
if (m == 0 || (((flags & MSG_DONTWAIT) == 0 &&
so->so_rcv.sb_cc < uio->uio_resid) &&
(so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) {
#ifdef DIAGNOSTIC
if (m == 0 && so->so_rcv.sb_cc)
panic("receive 1");
#endif
if (so->so_error) {
if (m)
goto dontblock;
error = so->so_error;
if ((flags & MSG_PEEK) == 0)
so->so_error = 0;
goto release;
}
if (so->so_state & SS_CANTRCVMORE) {
if (m)
goto dontblock;
else
goto release;
}
for (; m; m = m->m_next)
if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) {
m = so->so_rcv.sb_mb;
goto dontblock;
}
if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
(so->so_proto->pr_flags & PR_CONNREQUIRED)) {
error = ENOTCONN;
goto release;
}
if (uio->uio_resid == 0)
goto release;
if ((so->so_state & SS_NBIO) || (flags & MSG_DONTWAIT)) {
error = EWOULDBLOCK;
goto release;
}
SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1");
SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1");
sbunlock(&so->so_rcv);
error = sbwait(&so->so_rcv);
splx(s);
if (error)
return (error);
goto restart;
}
dontblock:
/*
* On entry here, m points to the first record of the socket buffer.
* While we process the initial mbufs containing address and control
* info, we save a copy of m->m_nextpkt into nextrecord.
*/
#ifdef notyet /* XXXX */
if (uio->uio_procp)
uio->uio_procp->p_stats->p_ru.ru_msgrcv++;
#endif
KASSERT(m == so->so_rcv.sb_mb);
SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
nextrecord = m->m_nextpkt;
if (pr->pr_flags & PR_ADDR) {
#ifdef DIAGNOSTIC
if (m->m_type != MT_SONAME)
panic("receive 1a");
#endif
orig_resid = 0;
if (flags & MSG_PEEK) {
if (paddr)
*paddr = m_copy(m, 0, m->m_len);
m = m->m_next;
} else {
sbfree(&so->so_rcv, m);
mbuf_removed = 1;
if (paddr) {
*paddr = m;
so->so_rcv.sb_mb = m->m_next;
m->m_next = 0;
m = so->so_rcv.sb_mb;
} else {
MFREE(m, so->so_rcv.sb_mb);
m = so->so_rcv.sb_mb;
}
}
}
while (m && m->m_type == MT_CONTROL && error == 0) {
if (flags & MSG_PEEK) {
if (controlp)
*controlp = m_copy(m, 0, m->m_len);
m = m->m_next;
} else {
sbfree(&so->so_rcv, m);
mbuf_removed = 1;
if (controlp) {
if (pr->pr_domain->dom_externalize &&
mtod(m, struct cmsghdr *)->cmsg_type ==
SCM_RIGHTS)
error = (*pr->pr_domain->dom_externalize)(m);
*controlp = m;
so->so_rcv.sb_mb = m->m_next;
m->m_next = 0;
m = so->so_rcv.sb_mb;
} else {
MFREE(m, so->so_rcv.sb_mb);
m = so->so_rcv.sb_mb;
}
}
if (controlp) {
orig_resid = 0;
controlp = &(*controlp)->m_next;
}
}
/*
* If m is non-NULL, we have some data to read. From now on,
* make sure to keep sb_lastrecord consistent when working on
* the last packet on the chain (nextrecord == NULL) and we
* change m->m_nextpkt.
*/
if (m) {
if ((flags & MSG_PEEK) == 0) {
m->m_nextpkt = nextrecord;
/*
* If nextrecord == NULL (this is a single chain),
* then sb_lastrecord may not be valid here if m
* was changed earlier.
*/
if (nextrecord == NULL) {
KASSERT(so->so_rcv.sb_mb == m);
so->so_rcv.sb_lastrecord = m;
}
}
type = m->m_type;
if (type == MT_OOBDATA)
flags |= MSG_OOB;
} else {
if ((flags & MSG_PEEK) == 0) {
KASSERT(so->so_rcv.sb_mb == m);
so->so_rcv.sb_mb = nextrecord;
SB_EMPTY_FIXUP(&so->so_rcv);
}
}
SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
moff = 0;
offset = 0;
while (m && uio->uio_resid > 0 && error == 0) {
if (m->m_type == MT_OOBDATA) {
if (type != MT_OOBDATA)
break;
} else if (type == MT_OOBDATA)
break;
#ifdef DIAGNOSTIC
else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
panic("receive 3");
#endif
so->so_state &= ~SS_RCVATMARK;
len = uio->uio_resid;
if (so->so_oobmark && len > so->so_oobmark - offset)
len = so->so_oobmark - offset;
if (len > m->m_len - moff)
len = m->m_len - moff;
/*
* If mp is set, just pass back the mbufs.
* Otherwise copy them out via the uio, then free.
* Sockbuf must be consistent here (points to current mbuf,
* it points to next record) when we drop priority;
* we must note any additions to the sockbuf when we
* block interrupts again.
*/
if (mp == 0) {
SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove");
SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove");
splx(s);
error = uiomove(mtod(m, caddr_t) + moff, (int)len, uio);
s = splsoftnet();
if (error) {
/*
* If any part of the record has been removed
* (such as the MT_SONAME mbuf, which will
* happen when PR_ADDR, and thus also
* PR_ATOMIC, is set), then drop the entire
* record to maintain the atomicity of the
* receive operation.
*
* This avoids a later panic("receive 1a")
* when compiled with DIAGNOSTIC.
*/
if (m && mbuf_removed
&& (pr->pr_flags & PR_ATOMIC))
(void) sbdroprecord(&so->so_rcv);
goto release;
}
} else
uio->uio_resid -= len;
if (len == m->m_len - moff) {
if (m->m_flags & M_EOR)
flags |= MSG_EOR;
if (flags & MSG_PEEK) {
m = m->m_next;
moff = 0;
} else {
nextrecord = m->m_nextpkt;
sbfree(&so->so_rcv, m);
if (mp) {
*mp = m;
mp = &m->m_next;
so->so_rcv.sb_mb = m = m->m_next;
*mp = (struct mbuf *)0;
} else {
MFREE(m, so->so_rcv.sb_mb);
m = so->so_rcv.sb_mb;
}
/*
* If m != NULL, we also know that
* so->so_rcv.sb_mb != NULL.
*/
KASSERT(so->so_rcv.sb_mb == m);
if (m) {
m->m_nextpkt = nextrecord;
if (nextrecord == NULL)
so->so_rcv.sb_lastrecord = m;
} else {
so->so_rcv.sb_mb = nextrecord;
SB_EMPTY_FIXUP(&so->so_rcv);
}
SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
}
} else {
if (flags & MSG_PEEK)
moff += len;
else {
if (mp)
*mp = m_copym(m, 0, len, M_WAIT);
m->m_data += len;
m->m_len -= len;
so->so_rcv.sb_cc -= len;
}
}
if (so->so_oobmark) {
if ((flags & MSG_PEEK) == 0) {
so->so_oobmark -= len;
if (so->so_oobmark == 0) {
so->so_state |= SS_RCVATMARK;
break;
}
} else {
offset += len;
if (offset == so->so_oobmark)
break;
}
}
if (flags & MSG_EOR)
break;
/*
* If the MSG_WAITALL flag is set (for non-atomic socket),
* we must not quit until "uio->uio_resid == 0" or an error
* termination. If a signal/timeout occurs, return
* with a short count but without error.
* Keep sockbuf locked against other readers.
*/
while (flags & MSG_WAITALL && m == 0 && uio->uio_resid > 0 &&
!sosendallatonce(so) && !nextrecord) {
if (so->so_error || so->so_state & SS_CANTRCVMORE)
break;
/*
* If we are peeking and the socket receive buffer is
* full, stop since we can't get more data to peek at.
*/
if ((flags & MSG_PEEK) && sbspace(&so->so_rcv) <= 0)
break;
/*
* If we've drained the socket buffer, tell the
* protocol in case it needs to do something to
* get it filled again.
*/
if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb)
(*pr->pr_usrreq)(so, PRU_RCVD,
(struct mbuf *)0,
(struct mbuf *)(long)flags,
(struct mbuf *)0,
(struct proc *)0);
SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2");
SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2");
error = sbwait(&so->so_rcv);
if (error) {
sbunlock(&so->so_rcv);
splx(s);
return (0);
}
if ((m = so->so_rcv.sb_mb) != NULL)
nextrecord = m->m_nextpkt;
}
}
if (m && pr->pr_flags & PR_ATOMIC) {
flags |= MSG_TRUNC;
if ((flags & MSG_PEEK) == 0)
(void) sbdroprecord(&so->so_rcv);
}
if ((flags & MSG_PEEK) == 0) {
if (m == 0) {
/*
* First part is an inline SB_EMPTY_FIXUP(). Second
* part makes sure sb_lastrecord is up-to-date if
* there is still data in the socket buffer.
*/
so->so_rcv.sb_mb = nextrecord;
if (so->so_rcv.sb_mb == NULL) {
so->so_rcv.sb_mbtail = NULL;
so->so_rcv.sb_lastrecord = NULL;
} else if (nextrecord->m_nextpkt == NULL)
so->so_rcv.sb_lastrecord = nextrecord;
}
SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
(*pr->pr_usrreq)(so, PRU_RCVD, (struct mbuf *)0,
(struct mbuf *)(long)flags, (struct mbuf *)0,
(struct proc *)0);
}
if (orig_resid == uio->uio_resid && orig_resid &&
(flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
sbunlock(&so->so_rcv);
splx(s);
goto restart;
}
if (flagsp)
*flagsp |= flags;
release:
sbunlock(&so->so_rcv);
splx(s);
return (error);
}
int
soshutdown(struct socket *so, int how)
{
struct protosw *pr;
pr = so->so_proto;
if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
return (EINVAL);
if (how == SHUT_RD || how == SHUT_RDWR)
sorflush(so);
if (how == SHUT_WR || how == SHUT_RDWR)
return (*pr->pr_usrreq)(so, PRU_SHUTDOWN, (struct mbuf *)0,
(struct mbuf *)0, (struct mbuf *)0, (struct proc *)0);
return (0);
}
void
sorflush(struct socket *so)
{
struct sockbuf *sb, asb;
struct protosw *pr;
int s;
sb = &so->so_rcv;
pr = so->so_proto;
sb->sb_flags |= SB_NOINTR;
(void) sblock(sb, M_WAITOK);
s = splnet();
socantrcvmore(so);
sbunlock(sb);
asb = *sb;
memset((caddr_t)sb, 0, sizeof(*sb));
splx(s);
if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose)
(*pr->pr_domain->dom_dispose)(asb.sb_mb);
sbrelease(&asb);
}
int
sosetopt(struct socket *so, int level, int optname, struct mbuf *m0)
{
int error;
struct mbuf *m;
error = 0;
m = m0;
if (level != SOL_SOCKET) {
if (so->so_proto && so->so_proto->pr_ctloutput)
return ((*so->so_proto->pr_ctloutput)
(PRCO_SETOPT, so, level, optname, &m0));
error = ENOPROTOOPT;
} else {
switch (optname) {
case SO_LINGER:
if (m == NULL || m->m_len != sizeof(struct linger)) {
error = EINVAL;
goto bad;
}
so->so_linger = mtod(m, struct linger *)->l_linger;
/* fall thru... */
case SO_DEBUG:
case SO_KEEPALIVE:
case SO_DONTROUTE:
case SO_USELOOPBACK:
case SO_BROADCAST:
case SO_REUSEADDR:
case SO_REUSEPORT:
case SO_OOBINLINE:
case SO_TIMESTAMP:
if (m == NULL || m->m_len < sizeof(int)) {
error = EINVAL;
goto bad;
}
if (*mtod(m, int *))
so->so_options |= optname;
else
so->so_options &= ~optname;
break;
case SO_SNDBUF:
case SO_RCVBUF:
case SO_SNDLOWAT:
case SO_RCVLOWAT:
{
int optval;
if (m == NULL || m->m_len < sizeof(int)) {
error = EINVAL;
goto bad;
}
/*
* Values < 1 make no sense for any of these
* options, so disallow them.
*/
optval = *mtod(m, int *);
if (optval < 1) {
error = EINVAL;
goto bad;
}
switch (optname) {
case SO_SNDBUF:
case SO_RCVBUF:
if (sbreserve(optname == SO_SNDBUF ?
&so->so_snd : &so->so_rcv,
(u_long) optval) == 0) {
error = ENOBUFS;
goto bad;
}
break;
/*
* Make sure the low-water is never greater than
* the high-water.
*/
case SO_SNDLOWAT:
so->so_snd.sb_lowat =
(optval > so->so_snd.sb_hiwat) ?
so->so_snd.sb_hiwat : optval;
break;
case SO_RCVLOWAT:
so->so_rcv.sb_lowat =
(optval > so->so_rcv.sb_hiwat) ?
so->so_rcv.sb_hiwat : optval;
break;
}
break;
}
case SO_SNDTIMEO:
case SO_RCVTIMEO:
{
struct timeval *tv;
short val;
if (m == NULL || m->m_len < sizeof(*tv)) {
error = EINVAL;
goto bad;
}
tv = mtod(m, struct timeval *);
if (tv->tv_sec * hz + tv->tv_usec / tick > SHRT_MAX) {
error = EDOM;
goto bad;
}
val = tv->tv_sec * hz + tv->tv_usec / tick;
switch (optname) {
case SO_SNDTIMEO:
so->so_snd.sb_timeo = val;
break;
case SO_RCVTIMEO:
so->so_rcv.sb_timeo = val;
break;
}
break;
}
default:
error = ENOPROTOOPT;
break;
}
if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
(void) ((*so->so_proto->pr_ctloutput)
(PRCO_SETOPT, so, level, optname, &m0));
m = NULL; /* freed by protocol */
}
}
bad:
if (m)
(void) m_free(m);
return (error);
}
int
sogetopt(struct socket *so, int level, int optname, struct mbuf **mp)
{
struct mbuf *m;
if (level != SOL_SOCKET) {
if (so->so_proto && so->so_proto->pr_ctloutput) {
return ((*so->so_proto->pr_ctloutput)
(PRCO_GETOPT, so, level, optname, mp));
} else
return (ENOPROTOOPT);
} else {
m = m_get(M_WAIT, MT_SOOPTS);
m->m_len = sizeof(int);
switch (optname) {
case SO_LINGER:
m->m_len = sizeof(struct linger);
mtod(m, struct linger *)->l_onoff =
so->so_options & SO_LINGER;
mtod(m, struct linger *)->l_linger = so->so_linger;
break;
case SO_USELOOPBACK:
case SO_DONTROUTE:
case SO_DEBUG:
case SO_KEEPALIVE:
case SO_REUSEADDR:
case SO_REUSEPORT:
case SO_BROADCAST:
case SO_OOBINLINE:
case SO_TIMESTAMP:
*mtod(m, int *) = so->so_options & optname;
break;
case SO_TYPE:
*mtod(m, int *) = so->so_type;
break;
case SO_ERROR:
*mtod(m, int *) = so->so_error;
so->so_error = 0;
break;
case SO_SNDBUF:
*mtod(m, int *) = so->so_snd.sb_hiwat;
break;
case SO_RCVBUF:
*mtod(m, int *) = so->so_rcv.sb_hiwat;
break;
case SO_SNDLOWAT:
*mtod(m, int *) = so->so_snd.sb_lowat;
break;
case SO_RCVLOWAT:
*mtod(m, int *) = so->so_rcv.sb_lowat;
break;
case SO_SNDTIMEO:
case SO_RCVTIMEO:
{
int val = (optname == SO_SNDTIMEO ?
so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
m->m_len = sizeof(struct timeval);
mtod(m, struct timeval *)->tv_sec = val / hz;
mtod(m, struct timeval *)->tv_usec =
(val % hz) * tick;
break;
}
default:
(void)m_free(m);
return (ENOPROTOOPT);
}
*mp = m;
return (0);
}
}
void
sohasoutofband(struct socket *so)
{
struct proc *p;
if (so->so_pgid < 0)
gsignal(-so->so_pgid, SIGURG);
else if (so->so_pgid > 0 && (p = pfind(so->so_pgid)) != 0)
psignal(p, SIGURG);
selwakeup(&so->so_rcv.sb_sel);
}
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