/* $NetBSD: uipc_socket.c,v 1.313 2024/12/06 18:44:00 riastradh Exp $ */

/* $NetBSD: uipc_socket.c,v 1.313 2024/12/06 18:44:00 riastradh Exp $ */

/*
* Copyright (c) 2002, 2007, 2008, 2009, 2023 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, and by Andrew Doran.
*
* 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.
*
* 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) 2004 The FreeBSD Foundation
* Copyright (c) 2004 Robert Watson
* 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. 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
*/

/*
* 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.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.313 2024/12/06 18:44:00 riastradh Exp $");

#ifdef _KERNEL_OPT
#include "opt_compat_netbsd.h"
#include "opt_mbuftrace.h"
#include "opt_multiprocessor.h" /* XXX */
#include "opt_pipe.h"
#include "opt_sctp.h"
#include "opt_sock_counters.h"
#include "opt_somaxkva.h"
#include "opt_sosend_loan.h"
#endif

#include <sys/param.h>
#include <sys/types.h>

#include <sys/compat_stub.h>
#include <sys/condvar.h>
#include <sys/domain.h>
#include <sys/event.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/kauth.h>
#include <sys/kernel.h>
#include <sys/kmem.h>
#include <sys/kthread.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/poll.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/resourcevar.h>
#include <sys/sdt.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/systm.h>
#include <sys/uidinfo.h>

#include <compat/sys/socket.h>
#include <compat/sys/time.h>

#include <uvm/uvm_extern.h>
#include <uvm/uvm_loan.h>
#include <uvm/uvm_page.h>

#ifdef SCTP
#include <netinet/sctp_route.h>
#endif

MALLOC_DEFINE(M_SONAME, "soname", "socket name");

extern const struct fileops socketops;

static int sooptions;
extern int somaxconn; /* patchable (XXX sysctl) */
int somaxconn = SOMAXCONN;
kmutex_t *softnet_lock;

#ifdef SOSEND_COUNTERS
#include <sys/device.h>

static struct evcnt sosend_loan_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "loan big");
static struct evcnt sosend_copy_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "copy big");
static struct evcnt sosend_copy_small = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "copy small");
static struct evcnt sosend_kvalimit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
NULL, "sosend", "kva limit");

#define SOSEND_COUNTER_INCR(ev) (ev)->ev_count++

EVCNT_ATTACH_STATIC(sosend_loan_big);
EVCNT_ATTACH_STATIC(sosend_copy_big);
EVCNT_ATTACH_STATIC(sosend_copy_small);
EVCNT_ATTACH_STATIC(sosend_kvalimit);
#else

#define SOSEND_COUNTER_INCR(ev) /* nothing */

#endif /* SOSEND_COUNTERS */

#if defined(SOSEND_NO_LOAN) || defined(MULTIPROCESSOR)
int sock_loan_thresh = -1;
#else
int sock_loan_thresh = 4096;
#endif

static kmutex_t so_pendfree_lock;
static struct mbuf *so_pendfree = NULL;

#ifndef SOMAXKVA
#define SOMAXKVA (16 * 1024 * 1024)
#endif
int somaxkva = SOMAXKVA;
static int socurkva;
static kcondvar_t socurkva_cv;

#ifndef SOFIXEDBUF
#define SOFIXEDBUF true
#endif
bool sofixedbuf = SOFIXEDBUF;

static kauth_listener_t socket_listener;

#define SOCK_LOAN_CHUNK 65536

static void sopendfree_thread(void *);
static kcondvar_t pendfree_thread_cv;
static lwp_t *sopendfree_lwp;

static void sysctl_kern_socket_setup(void);
static struct sysctllog *socket_sysctllog;

static vsize_t
sokvareserve(struct socket *so, vsize_t len)
{
int error;

mutex_enter(&so_pendfree_lock);
while (socurkva + len > somaxkva) {
SOSEND_COUNTER_INCR(&sosend_kvalimit);
error = cv_wait_sig(&socurkva_cv, &so_pendfree_lock);
if (error) {
len = 0;
break;
}
}
socurkva += len;
mutex_exit(&so_pendfree_lock);
return len;
}

static void
sokvaunreserve(vsize_t len)
{

mutex_enter(&so_pendfree_lock);
socurkva -= len;
cv_broadcast(&socurkva_cv);
mutex_exit(&so_pendfree_lock);
}

/*
* sokvaalloc: allocate kva for loan.
*/
vaddr_t
sokvaalloc(vaddr_t sva, vsize_t len, struct socket *so)
{
vaddr_t lva;

if (sokvareserve(so, len) == 0)
return 0;

lva = uvm_km_alloc(kernel_map, len, atop(sva) & uvmexp.colormask,
UVM_KMF_COLORMATCH | UVM_KMF_VAONLY | UVM_KMF_WAITVA);
if (lva == 0) {
sokvaunreserve(len);
return 0;
}

return lva;
}

/*
* sokvafree: free kva for loan.
*/
void
sokvafree(vaddr_t sva, vsize_t len)
{

uvm_km_free(kernel_map, sva, len, UVM_KMF_VAONLY);
sokvaunreserve(len);
}

static void
sodoloanfree(struct vm_page **pgs, void *buf, size_t size)
{
vaddr_t sva, eva;
vsize_t len;
int npgs;

KASSERT(pgs != NULL);

eva = round_page((vaddr_t) buf + size);
sva = trunc_page((vaddr_t) buf);
len = eva - sva;
npgs = len >> PAGE_SHIFT;

pmap_kremove(sva, len);
pmap_update(pmap_kernel());
uvm_unloan(pgs, npgs, UVM_LOAN_TOPAGE);
sokvafree(sva, len);
}

/*
* sopendfree_thread: free mbufs on "pendfree" list. Unlock and relock
* so_pendfree_lock when freeing mbufs.
*/
static void
sopendfree_thread(void *v)
{
struct mbuf *m, *next;
size_t rv;

mutex_enter(&so_pendfree_lock);

for (;;) {
rv = 0;
while (so_pendfree != NULL) {
m = so_pendfree;
so_pendfree = NULL;
mutex_exit(&so_pendfree_lock);

for (; m != NULL; m = next) {
next = m->m_next;
KASSERT((~m->m_flags & (M_EXT|M_EXT_PAGES)) ==
0);
KASSERT(m->m_ext.ext_refcnt == 0);

rv += m->m_ext.ext_size;
sodoloanfree(m->m_ext.ext_pgs, m->m_ext.ext_buf,
m->m_ext.ext_size);
pool_cache_put(mb_cache, m);
}

mutex_enter(&so_pendfree_lock);
}
if (rv)
cv_broadcast(&socurkva_cv);
cv_wait(&pendfree_thread_cv, &so_pendfree_lock);
}
panic("sopendfree_thread");
/* NOTREACHED */
}

void
soloanfree(struct mbuf *m, void *buf, size_t size, void *arg)
{

KASSERT(m != NULL);

/*
* postpone freeing mbuf.
*
* we can't do it in interrupt context
* because we need to put kva back to kernel_map.
*/

mutex_enter(&so_pendfree_lock);
m->m_next = so_pendfree;
so_pendfree = m;
cv_signal(&pendfree_thread_cv);
mutex_exit(&so_pendfree_lock);
}

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;
vaddr_t lva;
int npgs, error;
vaddr_t va;
int i;

if (VMSPACE_IS_KERNEL_P(uio->uio_vmspace))
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;

KASSERT(npgs <= M_EXT_MAXPAGES);

lva = sokvaalloc(sva, len, so);
if (lva == 0)
return 0;

error = uvm_loan(&uio->uio_vmspace->vm_map, sva, len,
m->m_ext.ext_pgs, UVM_LOAN_TOPAGE);
if (error) {
sokvafree(lva, len);
return 0;
}

for (i = 0, va = lva; i < npgs; i++, va += PAGE_SIZE)
pmap_kenter_pa(va, VM_PAGE_TO_PHYS(m->m_ext.ext_pgs[i]),
VM_PROT_READ, 0);
pmap_update(pmap_kernel());

lva += (vaddr_t) iov->iov_base & PAGE_MASK;

MEXTADD(m, (void *) lva, space, M_MBUF, soloanfree, so);
m->m_flags |= M_EXT_PAGES | M_EXT_ROMAP;

uio->uio_resid -= space;
/* uio_offset not updated, not set/used for write(2) */
uio->uio_iov->iov_base = (char *)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;
}

static int
socket_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
void *arg0, void *arg1, void *arg2, void *arg3)
{
int result;
enum kauth_network_req req;

result = KAUTH_RESULT_DEFER;
req = (enum kauth_network_req)(uintptr_t)arg0;

if ((action != KAUTH_NETWORK_SOCKET) &&
(action != KAUTH_NETWORK_BIND))
return result;

switch (req) {
case KAUTH_REQ_NETWORK_BIND_PORT:
result = KAUTH_RESULT_ALLOW;
break;

case KAUTH_REQ_NETWORK_SOCKET_DROP: {
/* Normal users can only drop their own connections. */
struct socket *so = (struct socket *)arg1;

if (so->so_cred && proc_uidmatch(cred, so->so_cred) == 0)
result = KAUTH_RESULT_ALLOW;

break;
}

case KAUTH_REQ_NETWORK_SOCKET_OPEN:
/* We allow "raw" routing/bluetooth sockets to anyone. */
switch ((u_long)arg1) {
case PF_ROUTE:
case PF_OROUTE:
case PF_BLUETOOTH:
case PF_CAN:
result = KAUTH_RESULT_ALLOW;
break;
default:
/* Privileged, let secmodel handle this. */
if ((u_long)arg2 == SOCK_RAW)
break;
result = KAUTH_RESULT_ALLOW;
break;
}
break;

case KAUTH_REQ_NETWORK_SOCKET_CANSEE:
result = KAUTH_RESULT_ALLOW;

break;

default:
break;
}

return result;
}

void
soinit(void)
{

sysctl_kern_socket_setup();

#ifdef SCTP
/* Update the SCTP function hooks if necessary*/

vec_sctp_add_ip_address = sctp_add_ip_address;
vec_sctp_delete_ip_address = sctp_delete_ip_address;
#endif

mutex_init(&so_pendfree_lock, MUTEX_DEFAULT, IPL_VM);
softnet_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
cv_init(&socurkva_cv, "sokva");
cv_init(&pendfree_thread_cv, "sopendfr");
soinit2();

/* Set the initial adjusted socket buffer size. */
if (sb_max_set(sb_max))
panic("bad initial sb_max value: %lu", sb_max);

socket_listener = kauth_listen_scope(KAUTH_SCOPE_NETWORK,
socket_listener_cb, NULL);
}

void
soinit1(void)
{
int error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL,
sopendfree_thread, NULL, &sopendfree_lwp, "sopendfree");
if (error)
panic("soinit1 %d", error);
}

/*
* socreate: create a new socket of the specified type and the protocol.
*
* => Caller may specify another socket for lock sharing (must not be held).
* => Returns the new socket without lock held.
*/
int
socreate(int dom, struct socket **aso, int type, int proto, struct lwp *l,
struct socket *lockso)
{
const struct protosw *prp;
struct socket *so;
uid_t uid;
int error;
kmutex_t *lock;

error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_SOCKET,
KAUTH_REQ_NETWORK_SOCKET_OPEN, KAUTH_ARG(dom), KAUTH_ARG(type),
KAUTH_ARG(proto));
if (error != 0)
return error;

if (proto)
prp = pffindproto(dom, proto, type);
else
prp = pffindtype(dom, type);
if (prp == NULL) {
/* no support for domain */
if (pffinddomain(dom) == 0)
return SET_ERROR(EAFNOSUPPORT);
/* no support for socket type */
if (proto == 0 && type != 0)
return SET_ERROR(EPROTOTYPE);
return SET_ERROR(EPROTONOSUPPORT);
}
if (prp->pr_usrreqs == NULL)
return SET_ERROR(EPROTONOSUPPORT);
if (prp->pr_type != type)
return SET_ERROR(EPROTOTYPE);

so = soget(true);
so->so_type = type;
so->so_proto = prp;
so->so_send = sosend;
so->so_receive = soreceive;
so->so_options = sooptions;
#ifdef MBUFTRACE
so->so_rcv.sb_mowner = &prp->pr_domain->dom_mowner;
so->so_snd.sb_mowner = &prp->pr_domain->dom_mowner;
so->so_mowner = &prp->pr_domain->dom_mowner;
#endif
uid = kauth_cred_geteuid(l->l_cred);
so->so_uidinfo = uid_find(uid);
so->so_egid = kauth_cred_getegid(l->l_cred);
so->so_cpid = l->l_proc->p_pid;

/*
* Lock assigned and taken during PCB attach, unless we share
* the lock with another socket, e.g. socketpair(2) case.
*/
if (lockso) {
/*
* lockso->so_lock should be stable at this point, so
* no need for atomic_load_*.
*/
lock = lockso->so_lock;
so->so_lock = lock;
mutex_obj_hold(lock);
mutex_enter(lock);
}

/* Attach the PCB (returns with the socket lock held). */
error = (*prp->pr_usrreqs->pr_attach)(so, proto);
KASSERT(solocked(so));

if (error) {
KASSERT(so->so_pcb == NULL);
so->so_state |= SS_NOFDREF;
sofree(so);
return error;
}
so->so_cred = kauth_cred_hold(l->l_cred);
sounlock(so);

*aso = so;
return 0;
}

/*
* fsocreate: create a socket and a file descriptor associated with it.
* Returns the allocated file structure in *fpp, but the descriptor
* is not visible yet for the process.
* Caller is responsible for calling fd_affix() for the returned *fpp once
* it's socket initialization is finished successfully, or fd_abort() if it's
* initialization fails.
*
*
* => On success, write file descriptor to *fdout and *fpp and return zero.
* => On failure, return non-zero; *fdout and *fpp will be undefined.
*/
int
fsocreate(int domain, struct socket **sop, int type, int proto, int *fdout,
file_t **fpp, struct socket *lockso)
{
lwp_t *l = curlwp;
int error, fd, flags;
struct socket *so;
file_t *fp;

flags = type & SOCK_FLAGS_MASK;
type &= ~SOCK_FLAGS_MASK;
error = socreate(domain, &so, type, proto, l, lockso);
if (error) {
return error;
}

if ((error = fd_allocfile(&fp, &fd)) != 0) {
soclose(so);
return error;
}
fd_set_exclose(l, fd, (flags & SOCK_CLOEXEC) != 0);
fp->f_flag = FREAD|FWRITE|((flags & SOCK_NONBLOCK) ? FNONBLOCK : 0)|
((flags & SOCK_NOSIGPIPE) ? FNOSIGPIPE : 0);
fp->f_type = DTYPE_SOCKET;
fp->f_ops = &socketops;
if (flags & SOCK_NONBLOCK) {
so->so_state |= SS_NBIO;
}
fp->f_socket = so;

if (sop != NULL) {
*sop = so;
}
*fdout = fd;
*fpp = fp;
return error;
}

int
sofamily(const struct socket *so)
{
const struct protosw *pr;
const struct domain *dom;

if ((pr = so->so_proto) == NULL)
return AF_UNSPEC;
if ((dom = pr->pr_domain) == NULL)
return AF_UNSPEC;
return dom->dom_family;
}

int
sobind(struct socket *so, struct sockaddr *nam, struct lwp *l)
{
int error;

solock(so);
if (nam->sa_family != so->so_proto->pr_domain->dom_family) {
sounlock(so);
return SET_ERROR(EAFNOSUPPORT);
}
error = (*so->so_proto->pr_usrreqs->pr_bind)(so, nam, l);
sounlock(so);
return error;
}

int
solisten(struct socket *so, int backlog, struct lwp *l)
{
int error;
short oldopt, oldqlimit;

solock(so);
if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
SS_ISDISCONNECTING)) != 0) {
sounlock(so);
return SET_ERROR(EINVAL);
}
oldopt = so->so_options;
oldqlimit = so->so_qlimit;
if (TAILQ_EMPTY(&so->so_q))
so->so_options |= SO_ACCEPTCONN;
if (backlog < 0)
backlog = 0;
so->so_qlimit = uimin(backlog, somaxconn);

error = (*so->so_proto->pr_usrreqs->pr_listen)(so, l);
if (error != 0) {
so->so_options = oldopt;
so->so_qlimit = oldqlimit;
sounlock(so);
return error;
}
sounlock(so);
return 0;
}

void
sofree(struct socket *so)
{
u_int refs;

KASSERT(solocked(so));

if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) {
sounlock(so);
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)) {
sounlock(so);
return;
}
}
if (so->so_rcv.sb_hiwat)
(void)chgsbsize(so->so_uidinfo, &so->so_rcv.sb_hiwat, 0,
RLIM_INFINITY);
if (so->so_snd.sb_hiwat)
(void)chgsbsize(so->so_uidinfo, &so->so_snd.sb_hiwat, 0,
RLIM_INFINITY);
sbrelease(&so->so_snd, so);
KASSERT(!cv_has_waiters(&so->so_cv));
KASSERT(!cv_has_waiters(&so->so_rcv.sb_cv));
KASSERT(!cv_has_waiters(&so->so_snd.sb_cv));
sorflush(so);
refs = so->so_aborting; /* XXX */
/* Remove accept filter if one is present. */
if (so->so_accf != NULL)
(void)accept_filt_clear(so);
sounlock(so);
if (refs == 0) /* XXX */
soput(so);
}

/*
* soclose: 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 error = 0;

solock(so);
if (so->so_options & SO_ACCEPTCONN) {
for (;;) {
if ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) {
KASSERT(solocked2(so, so2));
(void) soqremque(so2, 0);
/* soabort drops the lock. */
(void) soabort(so2);
solock(so);
continue;
}
if ((so2 = TAILQ_FIRST(&so->so_q)) != 0) {
KASSERT(solocked2(so, so2));
(void) soqremque(so2, 1);
/* soabort drops the lock. */
(void) soabort(so2);
solock(so);
continue;
}
break;
}
}
if (so->so_pcb == NULL)
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|SS_NBIO)) ==
(SS_ISDISCONNECTING|SS_NBIO))
goto drop;
while (so->so_state & SS_ISCONNECTED) {
error = sowait(so, true, so->so_linger * hz);
if (error)
break;
}
}
}
drop:
if (so->so_pcb) {
KASSERT(solocked(so));
(*so->so_proto->pr_usrreqs->pr_detach)(so);
}
discard:
KASSERT((so->so_state & SS_NOFDREF) == 0);
kauth_cred_free(so->so_cred);
so->so_cred = NULL;
so->so_state |= SS_NOFDREF;
sofree(so);
return error;
}

/*
* Must be called with the socket locked.. Will return with it unlocked.
*/
int
soabort(struct socket *so)
{
u_int refs;
int error;

KASSERT(solocked(so));
KASSERT(so->so_head == NULL);

so->so_aborting++; /* XXX */
error = (*so->so_proto->pr_usrreqs->pr_abort)(so);
refs = --so->so_aborting; /* XXX */
if (error || (refs == 0)) {
sofree(so);
} else {
sounlock(so);
}
return error;
}

int
soaccept(struct socket *so, struct sockaddr *nam)
{
int error;

KASSERT(solocked(so));
KASSERT((so->so_state & SS_NOFDREF) != 0);

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_usrreqs->pr_accept)(so, nam);
else
error = SET_ERROR(ECONNABORTED);

return error;
}

int
soconnect(struct socket *so, struct sockaddr *nam, struct lwp *l)
{
int error;

KASSERT(solocked(so));

if (so->so_options & SO_ACCEPTCONN)
return SET_ERROR(EOPNOTSUPP);
/*
* 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 = SET_ERROR(EISCONN);
} else {
if (nam->sa_family != so->so_proto->pr_domain->dom_family) {
return SET_ERROR(EAFNOSUPPORT);
}
error = (*so->so_proto->pr_usrreqs->pr_connect)(so, nam, l);
}

return error;
}

int
soconnect2(struct socket *so1, struct socket *so2)
{
KASSERT(solocked2(so1, so2));

return (*so1->so_proto->pr_usrreqs->pr_connect2)(so1, so2);
}

int
sodisconnect(struct socket *so)
{
int error;

KASSERT(solocked(so));

if ((so->so_state & SS_ISCONNECTED) == 0) {
error = SET_ERROR(ENOTCONN);
} else if (so->so_state & SS_ISDISCONNECTING) {
error = SET_ERROR(EALREADY);
} else {
error = (*so->so_proto->pr_usrreqs->pr_disconnect)(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 sockaddr *addr, struct uio *uio,
struct mbuf *top, struct mbuf *control, int flags, struct lwp *l)
{
struct mbuf **mp, *m;
long space, len, resid, clen, mlen;
int error, s, dontroute, atomic;
short wakeup_state = 0;

clen = 0;

/*
* solock() provides atomicity of access. splsoftnet() prevents
* protocol processing soft interrupts from interrupting us and
* blocking (expensive).
*/
s = splsoftnet();
solock(so);
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 = SET_ERROR(EINVAL);
goto out;
}
dontroute =
(flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
(so->so_proto->pr_flags & PR_ATOMIC);
l->l_ru.ru_msgsnd++;
if (control)
clen = control->m_len;
restart:
if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0)
goto out;
do {
if (so->so_state & SS_CANTSENDMORE) {
error = SET_ERROR(EPIPE);
goto release;
}
if (so->so_error) {
error = SET_ERROR(so->so_error);
if ((flags & MSG_PEEK) == 0)
so->so_error = 0;
goto release;
}
if ((so->so_state & SS_ISCONNECTED) == 0) {
if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
if (resid || clen == 0) {
error = SET_ERROR(ENOTCONN);
goto release;
}
} else if (addr == NULL) {
error = SET_ERROR(EDESTADDRREQ);
goto release;
}
}
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) {
error = SET_ERROR(EMSGSIZE);
goto release;
}
if (space < resid + clen &&
(atomic || space < so->so_snd.sb_lowat || space < clen)) {
if ((so->so_state & SS_NBIO) || (flags & MSG_NBIO)) {
error = SET_ERROR(EWOULDBLOCK);
goto release;
}
sbunlock(&so->so_snd);
if (wakeup_state & SS_RESTARTSYS) {
error = SET_ERROR(ERESTART);
goto out;
}
error = sbwait(&so->so_snd);
if (error)
goto out;
wakeup_state = so->so_state;
goto restart;
}
wakeup_state = 0;
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 {
sounlock(so);
splx(s);
if (top == NULL) {
m = m_gethdr(M_WAIT, MT_DATA);
mlen = MHLEN;
m->m_pkthdr.len = 0;
m_reset_rcvif(m);
} else {
m = m_get(M_WAIT, MT_DATA);
mlen = MLEN;
}
MCLAIM(m, so->so_snd.sb_mowner);
if (sock_loan_thresh >= 0 &&
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);
m_clget(m, M_DONTWAIT);
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)
m_align(m, len);
}
error = uiomove(mtod(m, void *), (int)len, uio);
have_data:
resid = uio->uio_resid;
m->m_len = len;
*mp = m;
top->m_pkthdr.len += len;
s = splsoftnet();
solock(so);
if (error != 0)
goto release;
mp = &m->m_next;
if (resid <= 0) {
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
break;
}
} while (space > 0 && atomic);

if (so->so_state & SS_CANTSENDMORE) {
error = SET_ERROR(EPIPE);
goto release;
}
if (dontroute)
so->so_options |= SO_DONTROUTE;
if (resid > 0)
so->so_state |= SS_MORETOCOME;
if (flags & MSG_OOB) {
error = (*so->so_proto->pr_usrreqs->pr_sendoob)(
so, top, control);
} else {
error = (*so->so_proto->pr_usrreqs->pr_send)(so,
top, addr, control, l);
}
if (dontroute)
so->so_options &= ~SO_DONTROUTE;
if (resid > 0)
so->so_state &= ~SS_MORETOCOME;
clen = 0;
control = NULL;
top = NULL;
mp = &top;
if (error != 0)
goto release;
} while (resid && space > 0);
} while (resid);

release:
sbunlock(&so->so_snd);
out:
sounlock(so);
splx(s);
m_freem(top);
m_freem(control);
return error;
}

/*
* Following replacement or removal of the first mbuf on the first
* mbuf chain of a socket buffer, push necessary state changes back
* into the socket buffer so that other consumers see the values
* consistently. 'nextrecord' is the caller's locally stored value of
* the original value of sb->sb_mb->m_nextpkt which must be restored
* when the lead mbuf changes. NOTE: 'nextrecord' may be NULL.
*/
static void
sbsync(struct sockbuf *sb, struct mbuf *nextrecord)
{

KASSERT(solocked(sb->sb_so));

/*
* First, update for the new value of nextrecord. If necessary,
* make it the first record.
*/
if (sb->sb_mb != NULL)
sb->sb_mb->m_nextpkt = nextrecord;
else
sb->sb_mb = nextrecord;

/*
* Now update any dependent socket buffer fields to reflect
* the new state. This is an inline of SB_EMPTY_FIXUP, with
* the addition of a second clause that takes care of the
* case where sb_mb has been updated, but remains the last
* record.
*/
if (sb->sb_mb == NULL) {
sb->sb_mbtail = NULL;
sb->sb_lastrecord = NULL;
} else if (sb->sb_mb->m_nextpkt == NULL)
sb->sb_lastrecord = sb->sb_mb;
}

/*
* 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 lwp *l = curlwp;
struct mbuf *m, **mp, *mt;
size_t len, offset, moff, orig_resid;
int atomic, flags, error, s, type;
const struct protosw *pr;
struct mbuf *nextrecord;
int mbuf_removed = 0;
const struct domain *dom;
short wakeup_state = 0;

pr = so->so_proto;
atomic = pr->pr_flags & PR_ATOMIC;
dom = pr->pr_domain;
mp = mp0;
type = 0;
orig_resid = uio->uio_resid;

if (paddr != NULL)
*paddr = NULL;
if (controlp != NULL)
*controlp = NULL;
if (flagsp != NULL)
flags = *flagsp &~ MSG_EOR;
else
flags = 0;

if (flags & MSG_OOB) {
m = m_get(M_WAIT, MT_DATA);
solock(so);
error = (*pr->pr_usrreqs->pr_recvoob)(so, m, flags & MSG_PEEK);
sounlock(so);
if (error)
goto bad;
do {
error = uiomove(mtod(m, void *),
MIN(uio->uio_resid, m->m_len), uio);
m = m_free(m);
} while (uio->uio_resid > 0 && error == 0 && m);
bad:
m_freem(m);
return error;
}
if (mp != NULL)
*mp = NULL;

/*
* solock() provides atomicity of access. splsoftnet() prevents
* protocol processing soft interrupts from interrupting us and
* blocking (expensive).
*/
s = splsoftnet();
solock(so);
restart:
if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0) {
sounlock(so);
splx(s);
return error;
}
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 == NULL ||
((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 == NULL && !atomic)) {
#ifdef DIAGNOSTIC
if (m == NULL && so->so_rcv.sb_cc)
panic("receive 1");
#endif
if (so->so_error || so->so_rerror) {
u_short *e;
if (m != NULL)
goto dontblock;
e = so->so_error ? &so->so_error : &so->so_rerror;
error = SET_ERROR(*e);
if ((flags & MSG_PEEK) == 0)
*e = 0;
goto release;
}
if (so->so_state & SS_CANTRCVMORE) {
if (m != NULL)
goto dontblock;
else
goto release;
}
for (; m != NULL; 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 = SET_ERROR(ENOTCONN);
goto release;
}
if (uio->uio_resid == 0)
goto release;
if ((so->so_state & SS_NBIO) ||
(flags & (MSG_DONTWAIT|MSG_NBIO))) {
error = SET_ERROR(EWOULDBLOCK);
goto release;
}
SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1");
SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1");
sbunlock(&so->so_rcv);
if (wakeup_state & SS_RESTARTSYS)
error = SET_ERROR(ERESTART);
else
error = sbwait(&so->so_rcv);
if (error != 0) {
sounlock(so);
splx(s);
return error;
}
wakeup_state = so->so_state;
goto restart;
}

dontblock:
/*
* On entry here, m points to the first record of the socket buffer.
* From this point onward, we maintain 'nextrecord' as a cache of the
* pointer to the next record in the socket buffer. We must keep the
* various socket buffer pointers and local stack versions of the
* pointers in sync, pushing out modifications before dropping the
* socket lock, and re-reading them when picking it up.
*
* Otherwise, we will race with the network stack appending new data
* or records onto the socket buffer by using inconsistent/stale
* versions of the field, possibly resulting in socket buffer
* corruption.
*
* By holding the high-level sblock(), we prevent simultaneous
* readers from pulling off the front of the socket buffer.
*/
if (l != NULL)
l->l_ru.ru_msgrcv++;
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) {
KASSERT(m->m_type == MT_SONAME);
orig_resid = 0;
if (flags & MSG_PEEK) {
if (paddr)
*paddr = m_copym(m, 0, m->m_len, M_DONTWAIT);
m = m->m_next;
} else {
sbfree(&so->so_rcv, m);
mbuf_removed = 1;
if (paddr != NULL) {
*paddr = m;
so->so_rcv.sb_mb = m->m_next;
m->m_next = NULL;
m = so->so_rcv.sb_mb;
} else {
m = so->so_rcv.sb_mb = m_free(m);
}
sbsync(&so->so_rcv, nextrecord);
}
}

if (pr->pr_flags & PR_ADDR_OPT) {
/*
* For SCTP we may be getting a whole message OR a partial
* delivery.
*/
if (m->m_type == MT_SONAME) {
orig_resid = 0;
if (flags & MSG_PEEK) {
if (paddr)
*paddr = m_copym(m, 0, m->m_len, M_DONTWAIT);
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 {
m = so->so_rcv.sb_mb = m_free(m);
}
sbsync(&so->so_rcv, nextrecord);
}
}
}

/*
* Process one or more MT_CONTROL mbufs present before any data mbufs
* in the first mbuf chain on the socket buffer. If MSG_PEEK, we
* just copy the data; if !MSG_PEEK, we call into the protocol to
* perform externalization (or freeing if controlp == NULL).
*/
if (__predict_false(m != NULL && m->m_type == MT_CONTROL)) {
struct mbuf *cm = NULL, *cmn;
struct mbuf **cme = &cm;

do {
if (flags & MSG_PEEK) {
if (controlp != NULL) {
*controlp = m_copym(m, 0, m->m_len, M_DONTWAIT);
controlp = (*controlp == NULL ? NULL :
&(*controlp)->m_next);
}
m = m->m_next;
} else {
sbfree(&so->so_rcv, m);
so->so_rcv.sb_mb = m->m_next;
m->m_next = NULL;
*cme = m;
cme = &(*cme)->m_next;
m = so->so_rcv.sb_mb;
}
} while (m != NULL && m->m_type == MT_CONTROL);
if ((flags & MSG_PEEK) == 0)
sbsync(&so->so_rcv, nextrecord);

for (; cm != NULL; cm = cmn) {
cmn = cm->m_next;
cm->m_next = NULL;
type = mtod(cm, struct cmsghdr *)->cmsg_type;
if (controlp != NULL) {
if (dom->dom_externalize != NULL &&
type == SCM_RIGHTS) {
sounlock(so);
splx(s);
error = (*dom->dom_externalize)(cm, l,
(flags & MSG_CMSG_CLOEXEC) ?
O_CLOEXEC : 0);
s = splsoftnet();
solock(so);
}
*controlp = cm;
while (*controlp != NULL)
controlp = &(*controlp)->m_next;
} else {
/*
* Dispose of any SCM_RIGHTS message that went
* through the read path rather than recv.
*/
if (dom->dom_dispose != NULL &&
type == SCM_RIGHTS) {
sounlock(so);
(*dom->dom_dispose)(cm);
solock(so);
}
m_freem(cm);
}
}
if (m != NULL)
nextrecord = so->so_rcv.sb_mb->m_nextpkt;
else
nextrecord = so->so_rcv.sb_mb;
orig_resid = 0;
}

/* If m is non-NULL, we have some data to read. */
if (__predict_true(m != NULL)) {
type = m->m_type;
if (type == MT_OOBDATA)
flags |= MSG_OOB;
}
SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");

moff = 0;
offset = 0;
while (m != NULL && uio->uio_resid > 0 && error == 0) {
/*
* If the type of mbuf has changed, end the receive
* operation and do a short read.
*/
if (m->m_type == MT_OOBDATA) {
if (type != MT_OOBDATA)
break;
} else if (type == MT_OOBDATA) {
break;
} else if (m->m_type == MT_CONTROL) {
break;
}
#ifdef DIAGNOSTIC
else if (m->m_type != MT_DATA && m->m_type != MT_HEADER) {
panic("%s: m_type=%d", __func__, m->m_type);
}
#endif

so->so_state &= ~SS_RCVATMARK;
wakeup_state = 0;
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 == NULL) {
SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove");
SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove");
sounlock(so);
splx(s);
error = uiomove(mtod(m, char *) + moff, len, uio);
s = splsoftnet();
solock(so);
if (error != 0) {
/*
* 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 && 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;
#ifdef SCTP
if (m->m_flags & M_NOTIFICATION)
flags |= MSG_NOTIFICATION;
#endif
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 = NULL;
} else {
m = so->so_rcv.sb_mb = m_free(m);
}
/*
* 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 != NULL) {
mt = m_copym(m, 0, len, M_NOWAIT);
if (__predict_false(mt == NULL)) {
sounlock(so);
mt = m_copym(m, 0, len, M_WAIT);
solock(so);
}
*mp = mt;
}
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;
}
} else {
so->so_state &= ~SS_POLLRDBAND;
}
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 == NULL && uio->uio_resid > 0 &&
!sosendallatonce(so) && !nextrecord) {
if (so->so_error || so->so_rerror ||
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_usrreqs->pr_rcvd)(so, flags, l);
SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2");
SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2");
if (wakeup_state & SS_RESTARTSYS)
error = SET_ERROR(ERESTART);
else
error = sbwait(&so->so_rcv);
if (error != 0) {
sbunlock(&so->so_rcv);
sounlock(so);
splx(s);
return 0;
}
if ((m = so->so_rcv.sb_mb) != NULL)
nextrecord = m->m_nextpkt;
wakeup_state = so->so_state;
}
}

if (m && atomic) {
flags |= MSG_TRUNC;
if ((flags & MSG_PEEK) == 0)
(void) sbdroprecord(&so->so_rcv);
}
if ((flags & MSG_PEEK) == 0) {
if (m == NULL) {
/*
* 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_usrreqs->pr_rcvd)(so, flags, l);
}
if (orig_resid == uio->uio_resid && orig_resid &&
(flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
sbunlock(&so->so_rcv);
goto restart;
}

if (flagsp != NULL)
*flagsp |= flags;
release:
sbunlock(&so->so_rcv);
sounlock(so);
splx(s);
return error;
}

int
soshutdown(struct socket *so, int how)
{
const struct protosw *pr;
int error;

KASSERT(solocked(so));

pr = so->so_proto;
if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
return SET_ERROR(EINVAL);

if (how == SHUT_RD || how == SHUT_RDWR) {
sorflush(so);
error = 0;
}
if (how == SHUT_WR || how == SHUT_RDWR)
error = (*pr->pr_usrreqs->pr_shutdown)(so);

return error;
}

void
sorestart(struct socket *so)
{
/*
* An application has called close() on an fd on which another
* of its threads has called a socket system call.
* Mark this and wake everyone up, and code that would block again
* instead returns ERESTART.
* On system call re-entry the fd is validated and EBADF returned.
* Any other fd will block again on the 2nd syscall.
*/
solock(so);
so->so_state |= SS_RESTARTSYS;
cv_broadcast(&so->so_cv);
cv_broadcast(&so->so_snd.sb_cv);
cv_broadcast(&so->so_rcv.sb_cv);
sounlock(so);
}

void
sorflush(struct socket *so)
{
struct sockbuf *sb, asb;
const struct protosw *pr;

KASSERT(solocked(so));

sb = &so->so_rcv;
pr = so->so_proto;
socantrcvmore(so);
sb->sb_flags |= SB_NOINTR;
(void )sblock(sb, M_WAITOK);
sbunlock(sb);
asb = *sb;
/*
* Clear most of the sockbuf structure, but leave some of the
* fields valid.
*/
memset(&sb->sb_startzero, 0,
sizeof(*sb) - offsetof(struct sockbuf, sb_startzero));
if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) {
sounlock(so);
(*pr->pr_domain->dom_dispose)(asb.sb_mb);
solock(so);
}
sbrelease(&asb, so);
}

/*
* internal set SOL_SOCKET options
*/
static int
sosetopt1(struct socket *so, const struct sockopt *sopt)
{
int error, opt;
int optval = 0; /* XXX: gcc */
struct linger l;
struct timeval tv;

opt = sopt->sopt_name;

switch (opt) {

case SO_ACCEPTFILTER:
error = accept_filt_setopt(so, sopt);
KASSERT(solocked(so));
break;

case SO_LINGER:
error = sockopt_get(sopt, &l, sizeof(l));
solock(so);
if (error)
break;
if (l.l_linger < 0 || l.l_linger > USHRT_MAX ||
l.l_linger > (INT_MAX / hz)) {
error = SET_ERROR(EDOM);
break;
}
so->so_linger = l.l_linger;
if (l.l_onoff)
so->so_options |= SO_LINGER;
else
so->so_options &= ~SO_LINGER;
break;

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:
case SO_NOSIGPIPE:
case SO_RERROR:
error = sockopt_getint(sopt, &optval);
solock(so);
if (error)
break;
if (optval)
so->so_options |= opt;
else
so->so_options &= ~opt;
break;

case SO_SNDBUF:
case SO_RCVBUF:
case SO_SNDLOWAT:
case SO_RCVLOWAT:
error = sockopt_getint(sopt, &optval);
solock(so);
if (error)
break;

/*
* Values < 1 make no sense for any of these
* options, so disallow them.
*/
if (optval < 1) {
error = SET_ERROR(EINVAL);
break;
}

switch (opt) {
case SO_SNDBUF:
if (sbreserve(&so->so_snd, (u_long)optval, so) == 0) {
error = SET_ERROR(ENOBUFS);
break;
}
if (sofixedbuf)
so->so_snd.sb_flags &= ~SB_AUTOSIZE;
break;

case SO_RCVBUF:
if (sbreserve(&so->so_rcv, (u_long)optval, so) == 0) {
error = SET_ERROR(ENOBUFS);
break;
}
if (sofixedbuf)
so->so_rcv.sb_flags &= ~SB_AUTOSIZE;
break;

/*
* Make sure the low-water is never greater than
* the high-water.
*/
case SO_SNDLOWAT:
if (optval > so->so_snd.sb_hiwat)
optval = so->so_snd.sb_hiwat;

so->so_snd.sb_lowat = optval;
break;

case SO_RCVLOWAT:
if (optval > so->so_rcv.sb_hiwat)
optval = so->so_rcv.sb_hiwat;

so->so_rcv.sb_lowat = optval;
break;
}
break;

case SO_SNDTIMEO:
case SO_RCVTIMEO:
solock(so);
error = sockopt_get(sopt, &tv, sizeof(tv));
if (error)
break;

if (tv.tv_sec < 0 || tv.tv_usec < 0 || tv.tv_usec >= 1000000) {
error = SET_ERROR(EDOM);
break;
}
if (tv.tv_sec > (INT_MAX - tv.tv_usec / tick) / hz) {
error = SET_ERROR(EDOM);
break;
}

optval = tv.tv_sec * hz + tv.tv_usec / tick;
if (optval == 0 && tv.tv_usec != 0)
optval = 1;

switch (opt) {
case SO_SNDTIMEO:
so->so_snd.sb_timeo = optval;
break;
case SO_RCVTIMEO:
so->so_rcv.sb_timeo = optval;
break;
}
break;

default:
MODULE_HOOK_CALL(uipc_socket_50_setopt1_hook,
(opt, so, sopt), enosys(), error);
if (error == ENOSYS || error == EPASSTHROUGH) {
solock(so);
error = SET_ERROR(ENOPROTOOPT);
}
break;
}
KASSERT(solocked(so));
return error;
}

int
sosetopt(struct socket *so, struct sockopt *sopt)
{
int error, prerr;

if (sopt->sopt_level == SOL_SOCKET) {
error = sosetopt1(so, sopt);
KASSERT(solocked(so));
} else {
error = SET_ERROR(ENOPROTOOPT);
solock(so);
}

if ((error == 0 || error == ENOPROTOOPT) &&
so->so_proto != NULL && so->so_proto->pr_ctloutput != NULL) {
/* give the protocol stack a shot */
prerr = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so, sopt);
if (prerr == 0)
error = 0;
else if (prerr != ENOPROTOOPT)
error = prerr;
}
sounlock(so);
return error;
}

/*
* so_setsockopt() is a wrapper providing a sockopt structure for sosetopt()
*/
int
so_setsockopt(struct lwp *l, struct socket *so, int level, int name,
const void *val, size_t valsize)
{
struct sockopt sopt;
int error;

KASSERT(valsize == 0 || val != NULL);

sockopt_init(&sopt, level, name, valsize);
sockopt_set(&sopt, val, valsize);

error = sosetopt(so, &sopt);

sockopt_destroy(&sopt);

return error;
}

/*
* internal get SOL_SOCKET options
*/
static int
sogetopt1(struct socket *so, struct sockopt *sopt)
{
int error, optval, opt;
struct linger l;
struct timeval tv;

switch ((opt = sopt->sopt_name)) {

case SO_ACCEPTFILTER:
error = accept_filt_getopt(so, sopt);
break;

case SO_LINGER:
l.l_onoff = (so->so_options & SO_LINGER) ? 1 : 0;
l.l_linger = so->so_linger;

error = sockopt_set(sopt, &l, sizeof(l));
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:
case SO_NOSIGPIPE:
case SO_RERROR:
case SO_ACCEPTCONN:
error = sockopt_setint(sopt, (so->so_options & opt) ? 1 : 0);
break;

case SO_TYPE:
error = sockopt_setint(sopt, so->so_type);
break;

case SO_ERROR:
if (so->so_error == 0) {
so->so_error = so->so_rerror;
so->so_rerror = 0;
}
error = sockopt_setint(sopt, so->so_error);
so->so_error = 0;
break;

case SO_SNDBUF:
error = sockopt_setint(sopt, so->so_snd.sb_hiwat);
break;

case SO_RCVBUF:
error = sockopt_setint(sopt, so->so_rcv.sb_hiwat);
break;

case SO_SNDLOWAT:
error = sockopt_setint(sopt, so->so_snd.sb_lowat);
break;

case SO_RCVLOWAT:
error = sockopt_setint(sopt, so->so_rcv.sb_lowat);
break;

case SO_SNDTIMEO:
case SO_RCVTIMEO:
optval = (opt == SO_SNDTIMEO ?
so->so_snd.sb_timeo : so->so_rcv.sb_timeo);

memset(&tv, 0, sizeof(tv));
tv.tv_sec = optval / hz;
tv.tv_usec = (optval % hz) * tick;

error = sockopt_set(sopt, &tv, sizeof(tv));
break;

case SO_OVERFLOWED:
error = sockopt_setint(sopt, so->so_rcv.sb_overflowed);
break;

default:
MODULE_HOOK_CALL(uipc_socket_50_getopt1_hook,
(opt, so, sopt), enosys(), error);
if (error)
error = SET_ERROR(ENOPROTOOPT);
break;
}

return error;
}

int
sogetopt(struct socket *so, struct sockopt *sopt)
{
int error;

solock(so);
if (sopt->sopt_level != SOL_SOCKET) {
if (so->so_proto && so->so_proto->pr_ctloutput) {
error = ((*so->so_proto->pr_ctloutput)
(PRCO_GETOPT, so, sopt));
} else
error = SET_ERROR(ENOPROTOOPT);
} else {
error = sogetopt1(so, sopt);
}
sounlock(so);
return error;
}

/*
* alloc sockopt data buffer buffer
* - will be released at destroy
*/
static int
sockopt_alloc(struct sockopt *sopt, size_t len, km_flag_t kmflag)
{
void *data;

KASSERT(sopt->sopt_size == 0);

if (len > sizeof(sopt->sopt_buf)) {
data = kmem_zalloc(len, kmflag);
if (data == NULL)
return SET_ERROR(ENOMEM);
sopt->sopt_data = data;
} else
sopt->sopt_data = sopt->sopt_buf;

sopt->sopt_size = len;
return 0;
}

/*
* initialise sockopt storage
* - MAY sleep during allocation
*/
void
sockopt_init(struct sockopt *sopt, int level, int name, size_t size)
{

memset(sopt, 0, sizeof(*sopt));

sopt->sopt_level = level;
sopt->sopt_name = name;
(void)sockopt_alloc(sopt, size, KM_SLEEP);
}

/*
* destroy sockopt storage
* - will release any held memory references
*/
void
sockopt_destroy(struct sockopt *sopt)
{

if (sopt->sopt_data != sopt->sopt_buf)
kmem_free(sopt->sopt_data, sopt->sopt_size);

memset(sopt, 0, sizeof(*sopt));
}

/*
* set sockopt value
* - value is copied into sockopt
* - memory is allocated when necessary, will not sleep
*/
int
sockopt_set(struct sockopt *sopt, const void *buf, size_t len)
{
int error;

if (sopt->sopt_size == 0) {
error = sockopt_alloc(sopt, len, KM_NOSLEEP);
if (error)
return error;
}

sopt->sopt_retsize = MIN(sopt->sopt_size, len);
if (sopt->sopt_retsize > 0) {
memcpy(sopt->sopt_data, buf, sopt->sopt_retsize);
}

return 0;
}

/*
* common case of set sockopt integer value
*/
int
sockopt_setint(struct sockopt *sopt, int val)
{

return sockopt_set(sopt, &val, sizeof(int));
}

/*
* get sockopt value
* - correct size must be given
*/
int
sockopt_get(const struct sockopt *sopt, void *buf, size_t len)
{

if (sopt->sopt_size != len)
return SET_ERROR(EINVAL);

memcpy(buf, sopt->sopt_data, len);
return 0;
}

/*
* common case of get sockopt integer value
*/
int
sockopt_getint(const struct sockopt *sopt, int *valp)
{

return sockopt_get(sopt, valp, sizeof(int));
}

/*
* set sockopt value from mbuf
* - ONLY for legacy code
* - mbuf is released by sockopt
* - will not sleep
*/
int
sockopt_setmbuf(struct sockopt *sopt, struct mbuf *m)
{
size_t len;
int error;

len = m_length(m);

if (sopt->sopt_size == 0) {
error = sockopt_alloc(sopt, len, KM_NOSLEEP);
if (error)
return error;
}

sopt->sopt_retsize = MIN(sopt->sopt_size, len);
m_copydata(m, 0, sopt->sopt_retsize, sopt->sopt_data);
m_freem(m);

return 0;
}

/*
* get sockopt value into mbuf
* - ONLY for legacy code
* - mbuf to be released by the caller
* - will not sleep
*/
struct mbuf *
sockopt_getmbuf(const struct sockopt *sopt)
{
struct mbuf *m;

if (sopt->sopt_size > MCLBYTES)
return NULL;

m = m_get(M_DONTWAIT, MT_SOOPTS);
if (m == NULL)
return NULL;

if (sopt->sopt_size > MLEN) {
MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
return NULL;
}
}

memcpy(mtod(m, void *), sopt->sopt_data, sopt->sopt_size);
m->m_len = sopt->sopt_size;

return m;
}

void
sohasoutofband(struct socket *so)
{

so->so_state |= SS_POLLRDBAND;
fownsignal(so->so_pgid, SIGURG, POLL_PRI, POLLPRI|POLLRDBAND, so);
selnotify(&so->so_rcv.sb_sel, POLLPRI | POLLRDBAND, NOTE_SUBMIT);
}

static void
filt_sordetach(struct knote *kn)
{
struct socket *so;

so = ((file_t *)kn->kn_obj)->f_socket;
solock(so);
if (selremove_knote(&so->so_rcv.sb_sel, kn))
so->so_rcv.sb_flags &= ~SB_KNOTE;
sounlock(so);
}

/*ARGSUSED*/
static int
filt_soread(struct knote *kn, long hint)
{
struct socket *so;
int rv;

so = ((file_t *)kn->kn_obj)->f_socket;
if (hint != NOTE_SUBMIT)
solock(so);
kn->kn_data = so->so_rcv.sb_cc;
if (so->so_state & SS_CANTRCVMORE) {
knote_set_eof(kn, 0);
kn->kn_fflags = so->so_error;
rv = 1;
} else if (so->so_error || so->so_rerror)
rv = 1;
else if (kn->kn_sfflags & NOTE_LOWAT)
rv = (kn->kn_data >= kn->kn_sdata);
else
rv = (kn->kn_data >= so->so_rcv.sb_lowat);
if (hint != NOTE_SUBMIT)
sounlock(so);
return rv;
}

static void
filt_sowdetach(struct knote *kn)
{
struct socket *so;

so = ((file_t *)kn->kn_obj)->f_socket;
solock(so);
if (selremove_knote(&so->so_snd.sb_sel, kn))
so->so_snd.sb_flags &= ~SB_KNOTE;
sounlock(so);
}

/*ARGSUSED*/
static int
filt_sowrite(struct knote *kn, long hint)
{
struct socket *so;
int rv;

so = ((file_t *)kn->kn_obj)->f_socket;
if (hint != NOTE_SUBMIT)
solock(so);
kn->kn_data = sbspace(&so->so_snd);
if (so->so_state & SS_CANTSENDMORE) {
knote_set_eof(kn, 0);
kn->kn_fflags = so->so_error;
rv = 1;
} else if (so->so_error)
rv = 1;
else if (((so->so_state & SS_ISCONNECTED) == 0) &&
(so->so_proto->pr_flags & PR_CONNREQUIRED))
rv = 0;
else if (kn->kn_sfflags & NOTE_LOWAT)
rv = (kn->kn_data >= kn->kn_sdata);
else
rv = (kn->kn_data >= so->so_snd.sb_lowat);
if (hint != NOTE_SUBMIT)
sounlock(so);
return rv;
}

static int
filt_soempty(struct knote *kn, long hint)
{
struct socket *so;
int rv;

so = ((file_t *)kn->kn_obj)->f_socket;
if (hint != NOTE_SUBMIT)
solock(so);
rv = (kn->kn_data = sbused(&so->so_snd)) == 0 ||
(so->so_options & SO_ACCEPTCONN) != 0;
if (hint != NOTE_SUBMIT)
sounlock(so);
return rv;
}

/*ARGSUSED*/
static int
filt_solisten(struct knote *kn, long hint)
{
struct socket *so;
int rv;

so = ((file_t *)kn->kn_obj)->f_socket;

/*
* Set kn_data to number of incoming connections, not
* counting partial (incomplete) connections.
*/
if (hint != NOTE_SUBMIT)
solock(so);
kn->kn_data = so->so_qlen;
rv = (kn->kn_data > 0);
if (hint != NOTE_SUBMIT)
sounlock(so);
return rv;
}

static const struct filterops solisten_filtops = {
.f_flags = FILTEROP_ISFD | FILTEROP_MPSAFE,
.f_attach = NULL,
.f_detach = filt_sordetach,
.f_event = filt_solisten,
};

static const struct filterops soread_filtops = {
.f_flags = FILTEROP_ISFD | FILTEROP_MPSAFE,
.f_attach = NULL,
.f_detach = filt_sordetach,
.f_event = filt_soread,
};

static const struct filterops sowrite_filtops = {
.f_flags = FILTEROP_ISFD | FILTEROP_MPSAFE,
.f_attach = NULL,
.f_detach = filt_sowdetach,
.f_event = filt_sowrite,
};

static const struct filterops soempty_filtops = {
.f_flags = FILTEROP_ISFD | FILTEROP_MPSAFE,
.f_attach = NULL,
.f_detach = filt_sowdetach,
.f_event = filt_soempty,
};

int
soo_kqfilter(struct file *fp, struct knote *kn)
{
struct socket *so;
struct sockbuf *sb;

so = ((file_t *)kn->kn_obj)->f_socket;
solock(so);
switch (kn->kn_filter) {
case EVFILT_READ:
if (so->so_options & SO_ACCEPTCONN)
kn->kn_fop = &solisten_filtops;
else
kn->kn_fop = &soread_filtops;
sb = &so->so_rcv;
break;
case EVFILT_WRITE:
kn->kn_fop = &sowrite_filtops;
sb = &so->so_snd;

#ifdef PIPE_SOCKETPAIR
if (so->so_state & SS_ISAPIPE) {
/* Other end of pipe has been closed. */
if (so->so_state & SS_ISDISCONNECTED) {
sounlock(so);
return SET_ERROR(EBADF);
}
}
#endif
break;
case EVFILT_EMPTY:
kn->kn_fop = &soempty_filtops;
sb = &so->so_snd;
break;
default:
sounlock(so);
return SET_ERROR(EINVAL);
}
selrecord_knote(&sb->sb_sel, kn);
sb->sb_flags |= SB_KNOTE;
sounlock(so);
return 0;
}

static int
sodopoll(struct socket *so, int events)
{
int revents;

revents = 0;

if (events & (POLLIN | POLLRDNORM))
if (soreadable(so))
revents |= events & (POLLIN | POLLRDNORM);

if (events & (POLLOUT | POLLWRNORM))
if (sowritable(so))
revents |= events & (POLLOUT | POLLWRNORM);

if (events & (POLLPRI | POLLRDBAND))
if (so->so_state & SS_POLLRDBAND)
revents |= events & (POLLPRI | POLLRDBAND);

return revents;
}

int
sopoll(struct socket *so, int events)
{
int revents = 0;

#ifndef DIAGNOSTIC
/*
* Do a quick, unlocked check in expectation that the socket
* will be ready for I/O. Don't do this check if DIAGNOSTIC,
* as the solocked() assertions will fail.
*/
if ((revents = sodopoll(so, events)) != 0)
return revents;
#endif

solock(so);
if ((revents = sodopoll(so, events)) == 0) {
if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) {
selrecord(curlwp, &so->so_rcv.sb_sel);
so->so_rcv.sb_flags |= SB_NOTIFY;
}

if (events & (POLLOUT | POLLWRNORM)) {
selrecord(curlwp, &so->so_snd.sb_sel);
so->so_snd.sb_flags |= SB_NOTIFY;
}
}
sounlock(so);

return revents;
}

struct mbuf **
sbsavetimestamp(int opt, struct mbuf **mp)
{
struct timeval tv;
int error;

memset(&tv, 0, sizeof(tv));
microtime(&tv);

MODULE_HOOK_CALL(uipc_socket_50_sbts_hook, (opt, &mp), enosys(), error);
if (error == 0)
return mp;

if (opt & SO_TIMESTAMP) {
*mp = sbcreatecontrol(&tv, sizeof(tv),
SCM_TIMESTAMP, SOL_SOCKET);
if (*mp)
mp = &(*mp)->m_next;
}
return mp;
}

#include <sys/sysctl.h>

static int sysctl_kern_somaxkva(SYSCTLFN_PROTO);
static int sysctl_kern_sbmax(SYSCTLFN_PROTO);

/*
* sysctl helper routine for kern.somaxkva. ensures that the given
* value is not too small.
* (XXX should we maybe make sure it's not too large as well?)
*/
static int
sysctl_kern_somaxkva(SYSCTLFN_ARGS)
{
int error, new_somaxkva;
struct sysctlnode node;

new_somaxkva = somaxkva;
node = *rnode;
node.sysctl_data = &new_somaxkva;
error = sysctl_lookup(SYSCTLFN_CALL(&node));
if (error || newp == NULL)
return error;

if (new_somaxkva < (16 * 1024 * 1024)) /* sanity */
return SET_ERROR(EINVAL);

mutex_enter(&so_pendfree_lock);
somaxkva = new_somaxkva;
cv_broadcast(&socurkva_cv);
mutex_exit(&so_pendfree_lock);

return error;
}

/*
* sysctl helper routine for kern.sbmax. Basically just ensures that
* any new value is not too small.
*/
static int
sysctl_kern_sbmax(SYSCTLFN_ARGS)
{
int error, new_sbmax;
struct sysctlnode node;

new_sbmax = sb_max;
node = *rnode;
node.sysctl_data = &new_sbmax;
error = sysctl_lookup(SYSCTLFN_CALL(&node));
if (error || newp == NULL)
return error;

KERNEL_LOCK(1, NULL);
error = sb_max_set(new_sbmax);
KERNEL_UNLOCK_ONE(NULL);

return error;
}

/*
* sysctl helper routine for kern.sooptions. Ensures that only allowed
* options can be set.
*/
static int
sysctl_kern_sooptions(SYSCTLFN_ARGS)
{
int error, new_options;
struct sysctlnode node;

new_options = sooptions;
node = *rnode;
node.sysctl_data = &new_options;
error = sysctl_lookup(SYSCTLFN_CALL(&node));
if (error || newp == NULL)
return error;

if (new_options & ~SO_DEFOPTS)
return SET_ERROR(EINVAL);

sooptions = new_options;

return 0;
}

static void
sysctl_kern_socket_setup(void)
{

KASSERT(socket_sysctllog == NULL);

sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "somaxkva",
SYSCTL_DESCR("Maximum amount of kernel memory to be "
"used for socket buffers"),
sysctl_kern_somaxkva, 0, NULL, 0,
CTL_KERN, KERN_SOMAXKVA, CTL_EOL);

sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_BOOL, "sofixedbuf",
SYSCTL_DESCR("Prevent scaling of fixed socket buffers"),
NULL, 0, &sofixedbuf, 0,
CTL_KERN, KERN_SOFIXEDBUF, CTL_EOL);

sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "sbmax",
SYSCTL_DESCR("Maximum socket buffer size"),
sysctl_kern_sbmax, 0, NULL, 0,
CTL_KERN, KERN_SBMAX, CTL_EOL);

sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "sooptions",
SYSCTL_DESCR("Default socket options"),
sysctl_kern_sooptions, 0, NULL, 0,
CTL_KERN, CTL_CREATE, CTL_EOL);
}