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gems-kernel/source/THIRDPARTY/xnu/bsd/kern/uipc_socket2.c

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add darwin/xnu functionality
2024-06-03 11:29:39 -05:00
/*
* Copyright (c) 1998-2020 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* 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_socket2.c 8.1 (Berkeley) 6/10/93
*/
/*
* NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
* support for mandatory and extensible security protections. This notice
* is included in support of clause 2.2 (b) of the Apple Public License,
* Version 2.0.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/domain.h>
#include <sys/kernel.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mcache.h>
#include <sys/protosw.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/unpcb.h>
#include <sys/ev.h>
#include <kern/locks.h>
#include <net/route.h>
#include <net/content_filter.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp_var.h>
#include <sys/kdebug.h>
#include <libkern/OSAtomic.h>
#if CONFIG_MACF
#include <security/mac_framework.h>
#endif
#include <mach/vm_param.h>
#if MPTCP
#include <netinet/mptcp_var.h>
#endif
#include <net/sockaddr_utils.h>
extern uint32_t net_wake_pkt_debug;
#define DBG_FNC_SBDROP NETDBG_CODE(DBG_NETSOCK, 4)
#define DBG_FNC_SBAPPEND NETDBG_CODE(DBG_NETSOCK, 5)
SYSCTL_DECL(_kern_ipc);
__private_extern__ u_int32_t net_io_policy_throttle_best_effort = 0;
SYSCTL_INT(_kern_ipc, OID_AUTO, throttle_best_effort,
CTLFLAG_RW | CTLFLAG_LOCKED, &net_io_policy_throttle_best_effort, 0, "");
static inline void sbcompress(struct sockbuf *, struct mbuf *, struct mbuf *);
static struct socket *sonewconn_internal(struct socket *, int);
static int sbappendcontrol_internal(struct sockbuf *, struct mbuf *,
struct mbuf *);
static void soevent_ifdenied(struct socket *);
static int sbappendrecord_common(struct sockbuf *sb, struct mbuf *m0, boolean_t nodrop);
static int sbappend_common(struct sockbuf *sb, struct mbuf *m, boolean_t nodrop);
/*
* Primitive routines for operating on sockets and socket buffers
*/
static int soqlimitcompat = 1;
static int soqlencomp = 0;
/*
* Based on the number of mbuf clusters configured, high_sb_max and sb_max can
* get scaled up or down to suit that memory configuration. high_sb_max is a
* higher limit on sb_max that is checked when sb_max gets set through sysctl.
*/
uint32_t sb_max = SB_MAX;
uint32_t high_sb_max = SB_MAX;
static uint32_t sb_efficiency = 8; /* parameter for sbreserve() */
uint32_t net_io_policy_log = 0; /* log socket policy changes */
#if CONFIG_PROC_UUID_POLICY
uint32_t net_io_policy_uuid = 1; /* enable UUID socket policy */
#endif /* CONFIG_PROC_UUID_POLICY */
/*
* Procedures to manipulate state flags of socket
* and do appropriate wakeups. Normal sequence from the
* active (originating) side is that soisconnecting() is
* called during processing of connect() call,
* resulting in an eventual call to soisconnected() if/when the
* connection is established. When the connection is torn down
* soisdisconnecting() is called during processing of disconnect() call,
* and soisdisconnected() is called when the connection to the peer
* is totally severed. The semantics of these routines are such that
* connectionless protocols can call soisconnected() and soisdisconnected()
* only, bypassing the in-progress calls when setting up a ``connection''
* takes no time.
*
* From the passive side, a socket is created with
* two queues of sockets: so_incomp for connections in progress
* and so_comp for connections already made and awaiting user acceptance.
* As a protocol is preparing incoming connections, it creates a socket
* structure queued on so_incomp by calling sonewconn(). When the connection
* is established, soisconnected() is called, and transfers the
* socket structure to so_comp, making it available to accept().
*
* If a socket is closed with sockets on either
* so_incomp or so_comp, these sockets are dropped.
*
* If higher level protocols are implemented in
* the kernel, the wakeups done here will sometimes
* cause software-interrupt process scheduling.
*/
void
soisconnecting(struct socket *so)
{
so->so_state &= ~(SS_ISCONNECTED | SS_ISDISCONNECTING);
so->so_state |= SS_ISCONNECTING;
sflt_notify(so, sock_evt_connecting, NULL);
}
void
soisconnected(struct socket *so)
{
/*
* If socket is subject to filter and is pending initial verdict,
* delay marking socket as connected and do not present the connected
* socket to user just yet.
*/
if (cfil_sock_connected_pending_verdict(so)) {
return;
}
so->so_state &= ~(SS_ISCONNECTING | SS_ISDISCONNECTING | SS_ISCONFIRMING);
so->so_state |= SS_ISCONNECTED;
soreserve_preconnect(so, 0);
sflt_notify(so, sock_evt_connected, NULL);
if (so->so_head != NULL && (so->so_state & SS_INCOMP)) {
struct socket *head = so->so_head;
int locked = 0;
/*
* Enforce lock order when the protocol has per socket locks
*/
if (head->so_proto->pr_getlock != NULL) {
socket_lock(head, 1);
so_acquire_accept_list(head, so);
locked = 1;
}
if (so->so_head == head && (so->so_state & SS_INCOMP)) {
so->so_state &= ~SS_INCOMP;
so->so_state |= SS_COMP;
TAILQ_REMOVE(&head->so_incomp, so, so_list);
TAILQ_INSERT_TAIL(&head->so_comp, so, so_list);
head->so_incqlen--;
/*
* We have to release the accept list in
* case a socket callback calls sock_accept()
*/
if (locked != 0) {
so_release_accept_list(head);
socket_unlock(so, 0);
}
sorwakeup(head);
wakeup_one((caddr_t)&head->so_timeo);
if (locked != 0) {
socket_unlock(head, 1);
socket_lock(so, 0);
}
} else if (locked != 0) {
so_release_accept_list(head);
socket_unlock(head, 1);
}
} else {
wakeup((caddr_t)&so->so_timeo);
sorwakeup(so);
sowwakeup(so);
soevent(so, SO_FILT_HINT_LOCKED | SO_FILT_HINT_CONNECTED |
SO_FILT_HINT_CONNINFO_UPDATED);
}
}
boolean_t
socanwrite(struct socket *so)
{
return (so->so_state & SS_ISCONNECTED) ||
!(so->so_proto->pr_flags & PR_CONNREQUIRED) ||
(so->so_flags1 & SOF1_PRECONNECT_DATA);
}
void
soisdisconnecting(struct socket *so)
{
so->so_state &= ~SS_ISCONNECTING;
so->so_state |= (SS_ISDISCONNECTING | SS_CANTRCVMORE | SS_CANTSENDMORE);
soevent(so, SO_FILT_HINT_LOCKED);
sflt_notify(so, sock_evt_disconnecting, NULL);
wakeup((caddr_t)&so->so_timeo);
sowwakeup(so);
sorwakeup(so);
}
void
soisdisconnected(struct socket *so)
{
so->so_state &= ~(SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING);
so->so_state |= (SS_CANTRCVMORE | SS_CANTSENDMORE | SS_ISDISCONNECTED);
soevent(so, SO_FILT_HINT_LOCKED | SO_FILT_HINT_DISCONNECTED |
SO_FILT_HINT_CONNINFO_UPDATED);
sflt_notify(so, sock_evt_disconnected, NULL);
wakeup((caddr_t)&so->so_timeo);
sowwakeup(so);
sorwakeup(so);
#if CONTENT_FILTER
/* Notify content filters as soon as we cannot send/receive data */
cfil_sock_notify_shutdown(so, SHUT_RDWR);
#endif /* CONTENT_FILTER */
}
/*
* This function will issue a wakeup like soisdisconnected but it will not
* notify the socket filters. This will avoid unlocking the socket
* in the midst of closing it.
*/
void
sodisconnectwakeup(struct socket *so)
{
so->so_state &= ~(SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING);
so->so_state |= (SS_CANTRCVMORE | SS_CANTSENDMORE | SS_ISDISCONNECTED);
soevent(so, SO_FILT_HINT_LOCKED | SO_FILT_HINT_DISCONNECTED |
SO_FILT_HINT_CONNINFO_UPDATED);
wakeup((caddr_t)&so->so_timeo);
sowwakeup(so);
sorwakeup(so);
#if CONTENT_FILTER
/* Notify content filters as soon as we cannot send/receive data */
cfil_sock_notify_shutdown(so, SHUT_RDWR);
#endif /* CONTENT_FILTER */
}
/*
* When an attempt at a new connection is noted on a socket
* which accepts connections, sonewconn is called. If the
* connection is possible (subject to space constraints, etc.)
* then we allocate a new structure, propoerly linked into the
* data structure of the original socket, and return this.
* Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED.
*/
static struct socket *
sonewconn_internal(struct socket *head, int connstatus)
{
int so_qlen, error = 0;
struct socket *so;
lck_mtx_t *mutex_held;
if (head->so_proto->pr_getlock != NULL) {
mutex_held = (*head->so_proto->pr_getlock)(head, 0);
} else {
mutex_held = head->so_proto->pr_domain->dom_mtx;
}
LCK_MTX_ASSERT(mutex_held, LCK_MTX_ASSERT_OWNED);
if (!soqlencomp) {
/*
* This is the default case; so_qlen represents the
* sum of both incomplete and completed queues.
*/
so_qlen = head->so_qlen;
} else {
/*
* When kern.ipc.soqlencomp is set to 1, so_qlen
* represents only the completed queue. Since we
* cannot let the incomplete queue goes unbounded
* (in case of SYN flood), we cap the incomplete
* queue length to at most somaxconn, and use that
* as so_qlen so that we fail immediately below.
*/
so_qlen = head->so_qlen - head->so_incqlen;
if (head->so_incqlen > somaxconn) {
so_qlen = somaxconn;
}
}
if (so_qlen >=
(soqlimitcompat ? head->so_qlimit : (3 * head->so_qlimit / 2))) {
return (struct socket *)0;
}
so = soalloc(1, SOCK_DOM(head), head->so_type);
if (so == NULL) {
return (struct socket *)0;
}
/* check if head was closed during the soalloc */
if (head->so_proto == NULL) {
sodealloc(so);
return (struct socket *)0;
}
so->so_type = head->so_type;
so->so_family = head->so_family;
so->so_protocol = head->so_protocol;
so->so_options = head->so_options & ~SO_ACCEPTCONN;
so->so_linger = head->so_linger;
so->so_state = head->so_state | SS_NOFDREF;
so->so_proto = head->so_proto;
so->so_timeo = head->so_timeo;
so->so_pgid = head->so_pgid;
kauth_cred_ref(head->so_cred);
so->so_cred = head->so_cred;
so->so_persona_id = head->so_persona_id;
so->last_pid = head->last_pid;
so->last_upid = head->last_upid;
memcpy(so->last_uuid, head->last_uuid, sizeof(so->last_uuid));
if (head->so_flags & SOF_DELEGATED) {
so->e_pid = head->e_pid;
so->e_upid = head->e_upid;
memcpy(so->e_uuid, head->e_uuid, sizeof(so->e_uuid));
}
/* inherit socket options stored in so_flags */
so->so_flags = head->so_flags &
(SOF_NOSIGPIPE | SOF_NOADDRAVAIL | SOF_REUSESHAREUID |
SOF_NOTIFYCONFLICT | SOF_BINDRANDOMPORT | SOF_NPX_SETOPTSHUT |
SOF_NODEFUNCT | SOF_PRIVILEGED_TRAFFIC_CLASS | SOF_NOTSENT_LOWAT |
SOF_DELEGATED);
so->so_flags1 |= SOF1_INBOUND;
so->so_usecount = 1;
so->next_lock_lr = 0;
so->next_unlock_lr = 0;
so->so_rcv.sb_flags |= SB_RECV; /* XXX */
so->so_rcv.sb_so = so->so_snd.sb_so = so;
/* inherit traffic management properties of listener */
so->so_flags1 |=
head->so_flags1 & (SOF1_TRAFFIC_MGT_SO_BACKGROUND | SOF1_TC_NET_SERV_TYPE |
SOF1_QOSMARKING_ALLOWED | SOF1_QOSMARKING_POLICY_OVERRIDE);
so->so_background_thread = head->so_background_thread;
so->so_traffic_class = head->so_traffic_class;
so->so_netsvctype = head->so_netsvctype;
if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) {
sodealloc(so);
return (struct socket *)0;
}
so->so_rcv.sb_flags |= (head->so_rcv.sb_flags & SB_USRSIZE);
so->so_snd.sb_flags |= (head->so_snd.sb_flags & SB_USRSIZE);
/*
* Must be done with head unlocked to avoid deadlock
* for protocol with per socket mutexes.
*/
if (head->so_proto->pr_unlock) {
socket_unlock(head, 0);
}
if (((*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL) != 0) ||
error) {
sodealloc(so);
if (head->so_proto->pr_unlock) {
socket_lock(head, 0);
}
return (struct socket *)0;
}
if (head->so_proto->pr_unlock) {
socket_lock(head, 0);
/*
* Radar 7385998 Recheck that the head is still accepting
* to avoid race condition when head is getting closed.
*/
if ((head->so_options & SO_ACCEPTCONN) == 0) {
so->so_state &= ~SS_NOFDREF;
soclose(so);
return (struct socket *)0;
}
}
if (so->so_proto->pr_copy_last_owner != NULL) {
(*so->so_proto->pr_copy_last_owner)(so, head);
}
os_atomic_inc(&so->so_proto->pr_domain->dom_refs, relaxed);
/* Insert in head appropriate lists */
so_acquire_accept_list(head, NULL);
so->so_head = head;
/*
* Since this socket is going to be inserted into the incomp
* queue, it can be picked up by another thread in
* tcp_dropdropablreq to get dropped before it is setup..
* To prevent this race, set in-progress flag which can be
* cleared later
*/
so->so_flags |= SOF_INCOMP_INPROGRESS;
if (connstatus) {
TAILQ_INSERT_TAIL(&head->so_comp, so, so_list);
so->so_state |= SS_COMP;
} else {
TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list);
so->so_state |= SS_INCOMP;
head->so_incqlen++;
}
head->so_qlen++;
so_release_accept_list(head);
/* Attach socket filters for this protocol */
sflt_initsock(so);
if (connstatus) {
so->so_state |= (short)connstatus;
sorwakeup(head);
wakeup((caddr_t)&head->so_timeo);
}
return so;
}
struct socket *
sonewconn(struct socket *head, int connstatus, const struct sockaddr *from)
{
int error = sflt_connectin(head, from);
if (error) {
return NULL;
}
return sonewconn_internal(head, connstatus);
}
/*
* Socantsendmore indicates that no more data will be sent on the
* socket; it would normally be applied to a socket when the user
* informs the system that no more data is to be sent, by the protocol
* code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data
* will be received, and will normally be applied to the socket by a
* protocol when it detects that the peer will send no more data.
* Data queued for reading in the socket may yet be read.
*/
void
socantsendmore(struct socket *so)
{
so->so_state |= SS_CANTSENDMORE;
soevent(so, SO_FILT_HINT_LOCKED | SO_FILT_HINT_CANTSENDMORE);
sflt_notify(so, sock_evt_cantsendmore, NULL);
sowwakeup(so);
}
void
socantrcvmore(struct socket *so)
{
so->so_state |= SS_CANTRCVMORE;
soevent(so, SO_FILT_HINT_LOCKED | SO_FILT_HINT_CANTRCVMORE);
sflt_notify(so, sock_evt_cantrecvmore, NULL);
sorwakeup(so);
}
/*
* Wait for data to arrive at/drain from a socket buffer.
*/
int
sbwait(struct sockbuf *sb)
{
boolean_t nointr = (sb->sb_flags & SB_NOINTR);
void *lr_saved = __builtin_return_address(0);
struct socket *so = sb->sb_so;
lck_mtx_t *mutex_held;
struct timespec ts;
int error = 0;
if (so == NULL) {
panic("%s: null so, sb=%p sb_flags=0x%x lr=%p",
__func__, sb, sb->sb_flags, lr_saved);
/* NOTREACHED */
} else if (so->so_usecount < 1) {
panic("%s: sb=%p sb_flags=0x%x sb_so=%p usecount=%d lr=%p "
"lrh= %s\n", __func__, sb, sb->sb_flags, so,
so->so_usecount, lr_saved, solockhistory_nr(so));
/* NOTREACHED */
}
if ((so->so_state & SS_DRAINING) || (so->so_flags & SOF_DEFUNCT)) {
error = EBADF;
if (so->so_flags & SOF_DEFUNCT) {
SODEFUNCTLOG("%s[%d, %s]: defunct so 0x%llu [%d,%d] "
"(%d)\n", __func__, proc_selfpid(),
proc_best_name(current_proc()),
so->so_gencnt,
SOCK_DOM(so), SOCK_TYPE(so), error);
}
return error;
}
if (so->so_proto->pr_getlock != NULL) {
mutex_held = (*so->so_proto->pr_getlock)(so, PR_F_WILLUNLOCK);
} else {
mutex_held = so->so_proto->pr_domain->dom_mtx;
}
LCK_MTX_ASSERT(mutex_held, LCK_MTX_ASSERT_OWNED);
ts.tv_sec = sb->sb_timeo.tv_sec;
ts.tv_nsec = sb->sb_timeo.tv_usec * 1000;
sb->sb_waiters++;
VERIFY(sb->sb_waiters != 0);
error = msleep((caddr_t)&sb->sb_cc, mutex_held,
nointr ? PSOCK : PSOCK | PCATCH,
nointr ? "sbwait_nointr" : "sbwait", &ts);
VERIFY(sb->sb_waiters != 0);
sb->sb_waiters--;
if (so->so_usecount < 1) {
panic("%s: 2 sb=%p sb_flags=0x%x sb_so=%p usecount=%d lr=%p "
"lrh= %s\n", __func__, sb, sb->sb_flags, so,
so->so_usecount, lr_saved, solockhistory_nr(so));
/* NOTREACHED */
}
if ((so->so_state & SS_DRAINING) || (so->so_flags & SOF_DEFUNCT)) {
error = EBADF;
if (so->so_flags & SOF_DEFUNCT) {
SODEFUNCTLOG("%s[%d, %s]: defunct so 0x%llu [%d,%d] "
"(%d)\n", __func__, proc_selfpid(),
proc_best_name(current_proc()),
so->so_gencnt,
SOCK_DOM(so), SOCK_TYPE(so), error);
}
}
return error;
}
void
sbwakeup(struct sockbuf *sb)
{
if (sb->sb_waiters > 0) {
wakeup((caddr_t)&sb->sb_cc);
}
}
/*
* Wakeup processes waiting on a socket buffer.
* Do asynchronous notification via SIGIO
* if the socket has the SS_ASYNC flag set.
*/
void
sowakeup(struct socket *so, struct sockbuf *sb, struct socket *so2)
{
if (so->so_flags & SOF_DEFUNCT) {
SODEFUNCTLOG("%s[%d, %s]: defunct so 0x%llu [%d,%d] si 0x%x, "
"fl 0x%x [%s]\n", __func__, proc_selfpid(),
proc_best_name(current_proc()),
so->so_gencnt, SOCK_DOM(so),
SOCK_TYPE(so), (uint32_t)sb->sb_sel.si_flags, sb->sb_flags,
(sb->sb_flags & SB_RECV) ? "rcv" : "snd");
}
sb->sb_flags &= ~SB_SEL;
selwakeup(&sb->sb_sel);
sbwakeup(sb);
if (so->so_state & SS_ASYNC) {
if (so->so_pgid < 0) {
gsignal(-so->so_pgid, SIGIO);
} else if (so->so_pgid > 0) {
proc_signal(so->so_pgid, SIGIO);
}
}
if (sb->sb_flags & SB_KNOTE) {
KNOTE(&sb->sb_sel.si_note, SO_FILT_HINT_LOCKED);
}
if (sb->sb_flags & SB_UPCALL) {
void (*sb_upcall)(struct socket *, void *, int);
caddr_t sb_upcallarg;
int lock = !(sb->sb_flags & SB_UPCALL_LOCK);
sb_upcall = sb->sb_upcall;
sb_upcallarg = sb->sb_upcallarg;
/* Let close know that we're about to do an upcall */
so->so_upcallusecount++;
if (lock) {
if (so2) {
struct unpcb *unp = sotounpcb(so2);
unp->unp_flags |= UNP_DONTDISCONNECT;
unp->rw_thrcount++;
socket_unlock(so2, 0);
}
socket_unlock(so, 0);
}
(*sb_upcall)(so, sb_upcallarg, M_DONTWAIT);
if (lock) {
if (so2 && so > so2) {
struct unpcb *unp;
socket_lock(so2, 0);
unp = sotounpcb(so2);
unp->rw_thrcount--;
if (unp->rw_thrcount == 0) {
unp->unp_flags &= ~UNP_DONTDISCONNECT;
wakeup(unp);
}
}
socket_lock(so, 0);
if (so2 && so < so2) {
struct unpcb *unp;
socket_lock(so2, 0);
unp = sotounpcb(so2);
unp->rw_thrcount--;
if (unp->rw_thrcount == 0) {
unp->unp_flags &= ~UNP_DONTDISCONNECT;
wakeup(unp);
}
}
}
so->so_upcallusecount--;
/* Tell close that it's safe to proceed */
if ((so->so_flags & SOF_CLOSEWAIT) &&
so->so_upcallusecount == 0) {
wakeup((caddr_t)&so->so_upcallusecount);
}
}
#if CONTENT_FILTER
/*
* Trap disconnection events for content filters
*/
if ((so->so_flags & SOF_CONTENT_FILTER) != 0) {
if ((sb->sb_flags & SB_RECV)) {
if (so->so_state & (SS_CANTRCVMORE)) {
cfil_sock_notify_shutdown(so, SHUT_RD);
}
} else {
if (so->so_state & (SS_CANTSENDMORE)) {
cfil_sock_notify_shutdown(so, SHUT_WR);
}
}
}
#endif /* CONTENT_FILTER */
}
/*
* Socket buffer (struct sockbuf) utility routines.
*
* Each socket contains two socket buffers: one for sending data and
* one for receiving data. Each buffer contains a queue of mbufs,
* information about the number of mbufs and amount of data in the
* queue, and other fields allowing select() statements and notification
* on data availability to be implemented.
*
* Data stored in a socket buffer is maintained as a list of records.
* Each record is a list of mbufs chained together with the m_next
* field. Records are chained together with the m_nextpkt field. The upper
* level routine soreceive() expects the following conventions to be
* observed when placing information in the receive buffer:
*
* 1. If the protocol requires each message be preceded by the sender's
* name, then a record containing that name must be present before
* any associated data (mbuf's must be of type MT_SONAME).
* 2. If the protocol supports the exchange of ``access rights'' (really
* just additional data associated with the message), and there are
* ``rights'' to be received, then a record containing this data
* should be present (mbuf's must be of type MT_RIGHTS).
* 3. If a name or rights record exists, then it must be followed by
* a data record, perhaps of zero length.
*
* Before using a new socket structure it is first necessary to reserve
* buffer space to the socket, by calling sbreserve(). This should commit
* some of the available buffer space in the system buffer pool for the
* socket (currently, it does nothing but enforce limits). The space
* should be released by calling sbrelease() when the socket is destroyed.
*/
/*
* Returns: 0 Success
* ENOBUFS
*/
int
soreserve(struct socket *so, uint32_t sndcc, uint32_t rcvcc)
{
if (sbreserve(&so->so_snd, sndcc) == 0) {
goto bad;
} else {
so->so_snd.sb_idealsize = sndcc;
}
if (sbreserve(&so->so_rcv, rcvcc) == 0) {
goto bad2;
} else {
so->so_rcv.sb_idealsize = rcvcc;
}
if (so->so_rcv.sb_lowat == 0) {
so->so_rcv.sb_lowat = 1;
}
if (so->so_snd.sb_lowat == 0) {
so->so_snd.sb_lowat = MCLBYTES;
}
if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) {
so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
}
return 0;
bad2:
so->so_snd.sb_flags &= ~SB_SEL;
selthreadclear(&so->so_snd.sb_sel);
sbrelease(&so->so_snd);
bad:
return ENOBUFS;
}
void
soreserve_preconnect(struct socket *so, unsigned int pre_cc)
{
/* As of now, same bytes for both preconnect read and write */
so->so_snd.sb_preconn_hiwat = pre_cc;
so->so_rcv.sb_preconn_hiwat = pre_cc;
}
/*
* Allot mbufs to a sockbuf.
* Attempt to scale mbmax so that mbcnt doesn't become limiting
* if buffering efficiency is near the normal case.
*/
int
sbreserve(struct sockbuf *sb, uint32_t cc)
{
if (cc > sb_max) {
/* We would not end up changing sb_cc, so return 0 */
if (sb->sb_hiwat == sb_max) {
return 0;
}
cc = sb_max;
}
if (cc > sb->sb_hiwat && (sb->sb_flags & SB_LIMITED)) {
return 0;
}
sb->sb_hiwat = cc;
sb->sb_mbmax = cc * sb_efficiency;
if (sb->sb_lowat > sb->sb_hiwat) {
sb->sb_lowat = sb->sb_hiwat;
}
return 1;
}
/*
* Free mbufs held by a socket, and reserved mbuf space.
*/
/* WARNING needs to do selthreadclear() before calling this */
void
sbrelease(struct sockbuf *sb)
{
sbflush(sb);
sb->sb_hiwat = 0;
sb->sb_mbmax = 0;
}
/*
* Routines to add and remove
* data from an mbuf queue.
*
* The routines sbappend() or sbappendrecord() are normally called to
* append new mbufs to a socket buffer, after checking that adequate
* space is available, comparing the function sbspace() with the amount
* of data to be added. sbappendrecord() differs from sbappend() in
* that data supplied is treated as the beginning of a new record.
* To place a sender's address, optional access rights, and data in a
* socket receive buffer, sbappendaddr() should be used. To place
* access rights and data in a socket receive buffer, sbappendrights()
* should be used. In either case, the new data begins a new record.
* Note that unlike sbappend() and sbappendrecord(), these routines check
* for the caller that there will be enough space to store the data.
* Each fails if there is not enough space, or if it cannot find mbufs
* to store additional information in.
*
* Reliable protocols may use the socket send buffer to hold data
* awaiting acknowledgement. Data is normally copied from a socket
* send buffer in a protocol with m_copy for output to a peer,
* and then removing the data from the socket buffer with sbdrop()
* or sbdroprecord() when the data is acknowledged by the peer.
*/
/*
* Append mbuf chain m to the last record in the
* socket buffer sb. The additional space associated
* the mbuf chain is recorded in sb. Empty mbufs are
* discarded and mbufs are compacted where possible.
*/
static int
sbappend_common(struct sockbuf *sb, struct mbuf *m, boolean_t nodrop)
{
struct socket *so = sb->sb_so;
struct soflow_hash_entry *dgram_flow_entry = NULL;
if (m == NULL || (sb->sb_flags & SB_DROP)) {
if (m != NULL && !nodrop) {
m_freem(m);
}
return 0;
}
SBLASTRECORDCHK(sb, "sbappend 1");
if (sb->sb_lastrecord != NULL && (sb->sb_mbtail->m_flags & M_EOR)) {
return sbappendrecord_common(sb, m, nodrop);
}
if (SOCK_DOM(sb->sb_so) == PF_INET || SOCK_DOM(sb->sb_so) == PF_INET6) {
ASSERT(nodrop == FALSE);
if (NEED_DGRAM_FLOW_TRACKING(so)) {
dgram_flow_entry = soflow_get_flow(so, NULL, NULL, NULL, m != NULL ? m_length(m) : 0, false, (m != NULL && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0);
}
if (sb->sb_flags & SB_RECV && !(m && m->m_flags & M_SKIPCFIL)) {
int error = sflt_data_in(so, NULL, &m, NULL, 0);
SBLASTRECORDCHK(sb, "sbappend 2");
#if CONTENT_FILTER
if (error == 0) {
error = cfil_sock_data_in(so, NULL, m, NULL, 0, dgram_flow_entry);
}
#endif /* CONTENT_FILTER */
if (error != 0) {
if (error != EJUSTRETURN) {
m_freem(m);
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
return 0;
}
} else if (m) {
m->m_flags &= ~M_SKIPCFIL;
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
}
/* If this is the first record, it's also the last record */
if (sb->sb_lastrecord == NULL) {
sb->sb_lastrecord = m;
}
sbcompress(sb, m, sb->sb_mbtail);
SBLASTRECORDCHK(sb, "sbappend 3");
return 1;
}
int
sbappend(struct sockbuf *sb, struct mbuf *m)
{
return sbappend_common(sb, m, FALSE);
}
int
sbappend_nodrop(struct sockbuf *sb, struct mbuf *m)
{
return sbappend_common(sb, m, TRUE);
}
/*
* Similar to sbappend, except that this is optimized for stream sockets.
*/
int
sbappendstream(struct sockbuf *sb, struct mbuf *m)
{
struct soflow_hash_entry *dgram_flow_entry = NULL;
struct socket *so = sb->sb_so;
if (m == NULL || (sb->sb_flags & SB_DROP)) {
if (m != NULL) {
m_freem(m);
}
return 0;
}
if (m->m_nextpkt != NULL || (sb->sb_mb != sb->sb_lastrecord)) {
panic("sbappendstream: nexpkt %p || mb %p != lastrecord %p",
m->m_nextpkt, sb->sb_mb, sb->sb_lastrecord);
/* NOTREACHED */
}
SBLASTMBUFCHK(sb, __func__);
if (SOCK_DOM(sb->sb_so) == PF_INET || SOCK_DOM(sb->sb_so) == PF_INET6) {
if (NEED_DGRAM_FLOW_TRACKING(so)) {
dgram_flow_entry = soflow_get_flow(so, NULL, NULL, NULL, m != NULL ? m_length(m) : 0, false, (m != NULL && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0);
}
if (sb->sb_flags & SB_RECV && !(m && m->m_flags & M_SKIPCFIL)) {
int error = sflt_data_in(so, NULL, &m, NULL, 0);
SBLASTRECORDCHK(sb, "sbappendstream 1");
#if CONTENT_FILTER
if (error == 0) {
error = cfil_sock_data_in(so, NULL, m, NULL, 0, dgram_flow_entry);
}
#endif /* CONTENT_FILTER */
if (error != 0) {
if (error != EJUSTRETURN) {
m_freem(m);
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
return 0;
}
} else if (m) {
m->m_flags &= ~M_SKIPCFIL;
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
}
sbcompress(sb, m, sb->sb_mbtail);
sb->sb_lastrecord = sb->sb_mb;
SBLASTRECORDCHK(sb, "sbappendstream 2");
return 1;
}
#ifdef SOCKBUF_DEBUG
void
sbcheck(struct sockbuf *sb)
{
struct mbuf *m;
struct mbuf *n = 0;
u_int32_t len = 0, mbcnt = 0;
lck_mtx_t *mutex_held;
if (sb->sb_so->so_proto->pr_getlock != NULL) {
mutex_held = (*sb->sb_so->so_proto->pr_getlock)(sb->sb_so, 0);
} else {
mutex_held = sb->sb_so->so_proto->pr_domain->dom_mtx;
}
LCK_MTX_ASSERT(mutex_held, LCK_MTX_ASSERT_OWNED);
if (sbchecking == 0) {
return;
}
for (m = sb->sb_mb; m; m = n) {
n = m->m_nextpkt;
for (; m; m = m->m_next) {
len += m->m_len;
mbcnt += _MSIZE;
/* XXX pretty sure this is bogus */
if (m->m_flags & M_EXT) {
mbcnt += m->m_ext.ext_size;
}
}
}
if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) {
panic("cc %ld != %ld || mbcnt %ld != %ld", len, sb->sb_cc,
mbcnt, sb->sb_mbcnt);
}
}
#endif
void
sblastrecordchk(struct sockbuf *sb, const char *where)
{
struct mbuf *m = sb->sb_mb;
while (m && m->m_nextpkt) {
m = m->m_nextpkt;
}
if (m != sb->sb_lastrecord) {
printf("sblastrecordchk: mb 0x%llx lastrecord 0x%llx "
"last 0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sb->sb_mb),
(uint64_t)VM_KERNEL_ADDRPERM(sb->sb_lastrecord),
(uint64_t)VM_KERNEL_ADDRPERM(m));
printf("packet chain:\n");
for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) {
printf("\t0x%llx\n", (uint64_t)VM_KERNEL_ADDRPERM(m));
}
panic("sblastrecordchk from %s", where);
}
}
void
sblastmbufchk(struct sockbuf *sb, const char *where)
{
struct mbuf *m = sb->sb_mb;
struct mbuf *n;
while (m && m->m_nextpkt) {
m = m->m_nextpkt;
}
while (m && m->m_next) {
m = m->m_next;
}
if (m != sb->sb_mbtail) {
printf("sblastmbufchk: mb 0x%llx mbtail 0x%llx last 0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sb->sb_mb),
(uint64_t)VM_KERNEL_ADDRPERM(sb->sb_mbtail),
(uint64_t)VM_KERNEL_ADDRPERM(m));
printf("packet tree:\n");
for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) {
printf("\t");
for (n = m; n != NULL; n = n->m_next) {
printf("0x%llx ",
(uint64_t)VM_KERNEL_ADDRPERM(n));
}
printf("\n");
}
panic("sblastmbufchk from %s", where);
}
}
/*
* Similar to sbappend, except the mbuf chain begins a new record.
*/
static int
sbappendrecord_common(struct sockbuf *sb, struct mbuf *m0, boolean_t nodrop)
{
struct soflow_hash_entry *dgram_flow_entry = NULL;
struct socket *so = sb->sb_so;
struct mbuf *m;
int space = 0;
if (m0 == NULL || (sb->sb_flags & SB_DROP)) {
if (m0 != NULL && nodrop == FALSE) {
m_freem(m0);
}
return 0;
}
for (m = m0; m != NULL; m = m->m_next) {
space += m->m_len;
}
if (space > sbspace(sb) && !(sb->sb_flags & SB_UNIX)) {
if (nodrop == FALSE) {
m_freem(m0);
}
return 0;
}
if (SOCK_DOM(sb->sb_so) == PF_INET || SOCK_DOM(sb->sb_so) == PF_INET6) {
ASSERT(nodrop == FALSE);
if (NEED_DGRAM_FLOW_TRACKING(so)) {
dgram_flow_entry = soflow_get_flow(so, NULL, NULL, NULL, m0 != NULL ? m_length(m0) : 0, false, (m0 != NULL && m0->m_pkthdr.rcvif) ? m0->m_pkthdr.rcvif->if_index : 0);
}
if (sb->sb_flags & SB_RECV && !(m0 && m0->m_flags & M_SKIPCFIL)) {
int error = sflt_data_in(sb->sb_so, NULL, &m0, NULL,
sock_data_filt_flag_record);
#if CONTENT_FILTER
if (error == 0) {
error = cfil_sock_data_in(sb->sb_so, NULL, m0, NULL, 0, dgram_flow_entry);
}
#endif /* CONTENT_FILTER */
if (error != 0) {
SBLASTRECORDCHK(sb, "sbappendrecord 1");
if (error != EJUSTRETURN) {
m_freem(m0);
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
return 0;
}
} else if (m0) {
m0->m_flags &= ~M_SKIPCFIL;
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
}
/*
* Note this permits zero length records.
*/
sballoc(sb, m0);
SBLASTRECORDCHK(sb, "sbappendrecord 2");
if (sb->sb_lastrecord != NULL) {
sb->sb_lastrecord->m_nextpkt = m0;
} else {
sb->sb_mb = m0;
}
sb->sb_lastrecord = m0;
sb->sb_mbtail = m0;
m = m0->m_next;
m0->m_next = 0;
if (m && (m0->m_flags & M_EOR)) {
m0->m_flags &= ~M_EOR;
m->m_flags |= M_EOR;
}
sbcompress(sb, m, m0);
SBLASTRECORDCHK(sb, "sbappendrecord 3");
return 1;
}
int
sbappendrecord(struct sockbuf *sb, struct mbuf *m0)
{
return sbappendrecord_common(sb, m0, FALSE);
}
int
sbappendrecord_nodrop(struct sockbuf *sb, struct mbuf *m0)
{
return sbappendrecord_common(sb, m0, TRUE);
}
/*
* Concatenate address (optional), control (optional) and data into one
* single mbuf chain. If sockbuf *sb is passed in, space check will be
* performed.
*
* Returns: mbuf chain pointer if succeeded, NULL if failed
*/
struct mbuf *
sbconcat_mbufs(struct sockbuf *sb, struct sockaddr *asa, struct mbuf *m0, struct mbuf *control)
{
struct mbuf *m = NULL, *n = NULL;
int space = 0;
if (m0 && (m0->m_flags & M_PKTHDR) == 0) {
panic("sbconcat_mbufs");
}
if (m0) {
space += m0->m_pkthdr.len;
}
for (n = control; n; n = n->m_next) {
space += n->m_len;
if (n->m_next == 0) { /* keep pointer to last control buf */
break;
}
}
if (asa != NULL) {
_CASSERT(sizeof(asa->sa_len) == sizeof(__uint8_t));
#if _MSIZE <= UINT8_MAX
if (asa->sa_len > MLEN) {
return NULL;
}
#endif
_CASSERT(sizeof(asa->sa_len) == sizeof(__uint8_t));
space += asa->sa_len;
}
if (sb != NULL && space > sbspace(sb)) {
return NULL;
}
if (n) {
n->m_next = m0; /* concatenate data to control */
} else {
control = m0;
}
if (asa != NULL) {
MGET(m, M_DONTWAIT, MT_SONAME);
if (m == 0) {
if (n) {
/* unchain control and data if necessary */
n->m_next = NULL;
}
return NULL;
}
m->m_len = asa->sa_len;
bcopy((caddr_t)asa, mtod(m, caddr_t), asa->sa_len);
m->m_next = control;
} else {
m = control;
}
return m;
}
/*
* Queue mbuf chain to the receive queue of a socket.
* Parameter space is the total len of the mbuf chain.
* If passed in, sockbuf space will be checked.
*
* Returns: 0 Invalid mbuf chain
* 1 Success
*/
int
sbappendchain(struct sockbuf *sb, struct mbuf *m, int space)
{
struct mbuf *n, *nlast;
if (m == NULL) {
return 0;
}
if (space != 0 && space > sbspace(sb)) {
return 0;
}
for (n = m; n->m_next != NULL; n = n->m_next) {
sballoc(sb, n);
}
sballoc(sb, n);
nlast = n;
if (sb->sb_lastrecord != NULL) {
sb->sb_lastrecord->m_nextpkt = m;
} else {
sb->sb_mb = m;
}
sb->sb_lastrecord = m;
sb->sb_mbtail = nlast;
SBLASTMBUFCHK(sb, __func__);
SBLASTRECORDCHK(sb, "sbappendadddr 2");
return 1;
}
/*
* Returns: 0 Error: No space/out of mbufs/etc.
* 1 Success
*
* Imputed: (*error_out) errno for error
* ENOBUFS
* sflt_data_in:??? [whatever a filter author chooses]
*/
int
sbappendaddr(struct sockbuf *sb, struct sockaddr *asa, struct mbuf *m0,
struct mbuf *control, int *error_out)
{
int result = 0;
boolean_t sb_unix = (sb->sb_flags & SB_UNIX);
struct mbuf *mbuf_chain = NULL;
struct soflow_hash_entry *dgram_flow_entry = NULL;
struct socket *so = sb->sb_so;
if (error_out) {
*error_out = 0;
}
if (m0 && (m0->m_flags & M_PKTHDR) == 0) {
panic("sbappendaddrorfree");
}
if (sb->sb_flags & SB_DROP) {
if (m0 != NULL) {
m_freem(m0);
}
if (control != NULL && !sb_unix) {
m_freem(control);
}
if (error_out != NULL) {
*error_out = EINVAL;
}
return 0;
}
if (SOCK_DOM(sb->sb_so) == PF_INET || SOCK_DOM(sb->sb_so) == PF_INET6) {
/* Call socket data in filters */
if (NEED_DGRAM_FLOW_TRACKING(so)) {
dgram_flow_entry = soflow_get_flow(so, NULL, asa, control, m0 != NULL ? m_length(m0) : 0, false, (m0 != NULL && m0->m_pkthdr.rcvif) ? m0->m_pkthdr.rcvif->if_index : 0);
}
if (sb->sb_flags & SB_RECV && !(m0 && m0->m_flags & M_SKIPCFIL)) {
int error;
error = sflt_data_in(sb->sb_so, asa, &m0, &control, 0);
SBLASTRECORDCHK(sb, __func__);
#if CONTENT_FILTER
if (error == 0) {
error = cfil_sock_data_in(sb->sb_so, asa, m0, control,
0, dgram_flow_entry);
}
#endif /* CONTENT_FILTER */
if (error) {
if (error != EJUSTRETURN) {
if (m0) {
m_freem(m0);
}
if (control != NULL && !sb_unix) {
m_freem(control);
}
if (error_out) {
*error_out = error;
}
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
return 0;
}
} else if (m0) {
m0->m_flags &= ~M_SKIPCFIL;
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
}
mbuf_chain = sbconcat_mbufs(sb, asa, m0, control);
SBLASTRECORDCHK(sb, "sbappendadddr 1");
result = sbappendchain(sb, mbuf_chain, 0);
if (result == 0) {
if (m0) {
m_freem(m0);
}
if (control != NULL && !sb_unix) {
m_freem(control);
}
if (error_out) {
*error_out = ENOBUFS;
}
}
return result;
}
inline boolean_t
is_cmsg_valid(struct mbuf *control, struct cmsghdr *cmsg)
{
if (cmsg == NULL) {
return FALSE;
}
if (cmsg->cmsg_len < sizeof(struct cmsghdr)) {
return FALSE;
}
if ((uint8_t *)control->m_data >= (uint8_t *)cmsg + cmsg->cmsg_len) {
return FALSE;
}
if ((uint8_t *)control->m_data + control->m_len <
(uint8_t *)cmsg + cmsg->cmsg_len) {
return FALSE;
}
return TRUE;
}
static int
sbappendcontrol_internal(struct sockbuf *sb, struct mbuf *m0,
struct mbuf *control)
{
struct mbuf *m, *mlast, *n;
int space = 0;
if (control == 0) {
panic("sbappendcontrol");
}
for (m = control;; m = m->m_next) {
space += m->m_len;
if (m->m_next == 0) {
break;
}
}
n = m; /* save pointer to last control buffer */
for (m = m0; m; m = m->m_next) {
space += m->m_len;
}
if (space > sbspace(sb) && !(sb->sb_flags & SB_UNIX)) {
return 0;
}
n->m_next = m0; /* concatenate data to control */
SBLASTRECORDCHK(sb, "sbappendcontrol 1");
for (m = control; m->m_next != NULL; m = m->m_next) {
sballoc(sb, m);
}
sballoc(sb, m);
mlast = m;
if (sb->sb_lastrecord != NULL) {
sb->sb_lastrecord->m_nextpkt = control;
} else {
sb->sb_mb = control;
}
sb->sb_lastrecord = control;
sb->sb_mbtail = mlast;
SBLASTMBUFCHK(sb, __func__);
SBLASTRECORDCHK(sb, "sbappendcontrol 2");
return 1;
}
int
sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, struct mbuf *control,
int *error_out)
{
struct soflow_hash_entry *dgram_flow_entry = NULL;
struct socket *so = sb->sb_so;
int result = 0;
boolean_t sb_unix = (sb->sb_flags & SB_UNIX);
if (error_out) {
*error_out = 0;
}
if (sb->sb_flags & SB_DROP) {
if (m0 != NULL) {
m_freem(m0);
}
if (control != NULL && !sb_unix) {
m_freem(control);
}
if (error_out != NULL) {
*error_out = EINVAL;
}
return 0;
}
if (SOCK_DOM(sb->sb_so) == PF_INET || SOCK_DOM(sb->sb_so) == PF_INET6) {
if (NEED_DGRAM_FLOW_TRACKING(so)) {
dgram_flow_entry = soflow_get_flow(so, NULL, NULL, control, m0 != NULL ? m_length(m0) : 0, false, (m0 != NULL && m0->m_pkthdr.rcvif) ? m0->m_pkthdr.rcvif->if_index : 0);
}
if (sb->sb_flags & SB_RECV && !(m0 && m0->m_flags & M_SKIPCFIL)) {
int error;
error = sflt_data_in(sb->sb_so, NULL, &m0, &control, 0);
SBLASTRECORDCHK(sb, __func__);
#if CONTENT_FILTER
if (error == 0) {
error = cfil_sock_data_in(sb->sb_so, NULL, m0, control,
0, dgram_flow_entry);
}
#endif /* CONTENT_FILTER */
if (error) {
if (error != EJUSTRETURN) {
if (m0) {
m_freem(m0);
}
if (control != NULL && !sb_unix) {
m_freem(control);
}
if (error_out) {
*error_out = error;
}
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
return 0;
}
} else if (m0) {
m0->m_flags &= ~M_SKIPCFIL;
}
if (dgram_flow_entry != NULL) {
soflow_free_flow(dgram_flow_entry);
}
}
result = sbappendcontrol_internal(sb, m0, control);
if (result == 0) {
if (m0) {
m_freem(m0);
}
if (control != NULL && !sb_unix) {
m_freem(control);
}
if (error_out) {
*error_out = ENOBUFS;
}
}
return result;
}
/*
* TCP streams have Multipath TCP support or are regular TCP sockets.
*/
int
sbappendstream_rcvdemux(struct socket *so, struct mbuf *m)
{
int ret = 0;
if ((m != NULL) &&
m_pktlen(m) <= 0 &&
!((so->so_flags & SOF_MP_SUBFLOW) &&
(m->m_flags & M_PKTHDR) &&
(m->m_pkthdr.pkt_flags & PKTF_MPTCP_DFIN))) {
m_freem(m);
return ret;
}
#if MPTCP
if (so->so_flags & SOF_MP_SUBFLOW) {
return sbappendmptcpstream_rcv(&so->so_rcv, m);
} else
#endif /* MPTCP */
{
return sbappendstream(&so->so_rcv, m);
}
}
#if MPTCP
int
sbappendmptcpstream_rcv(struct sockbuf *sb, struct mbuf *m)
{
struct socket *so = sb->sb_so;
VERIFY(m == NULL || (m->m_flags & M_PKTHDR));
/* SB_NOCOMPRESS must be set prevent loss of M_PKTHDR data */
VERIFY((sb->sb_flags & (SB_RECV | SB_NOCOMPRESS)) ==
(SB_RECV | SB_NOCOMPRESS));
if (m == NULL || m_pktlen(m) == 0 || (sb->sb_flags & SB_DROP) ||
(so->so_state & SS_CANTRCVMORE)) {
if (m && (m->m_flags & M_PKTHDR) &&
m_pktlen(m) == 0 &&
(m->m_pkthdr.pkt_flags & PKTF_MPTCP_DFIN)) {
mptcp_input(tptomptp(sototcpcb(so))->mpt_mpte, m);
return 1;
} else if (m != NULL) {
m_freem(m);
}
return 0;
}
/* the socket is not closed, so SOF_MP_SUBFLOW must be set */
VERIFY(so->so_flags & SOF_MP_SUBFLOW);
if (m->m_nextpkt != NULL || (sb->sb_mb != sb->sb_lastrecord)) {
panic("%s: nexpkt %p || mb %p != lastrecord %p", __func__,
m->m_nextpkt, sb->sb_mb, sb->sb_lastrecord);
/* NOTREACHED */
}
SBLASTMBUFCHK(sb, __func__);
/* No filter support (SB_RECV) on mptcp subflow sockets */
sbcompress(sb, m, sb->sb_mbtail);
sb->sb_lastrecord = sb->sb_mb;
SBLASTRECORDCHK(sb, __func__);
return 1;
}
#endif /* MPTCP */
/*
* Compress mbuf chain m into the socket
* buffer sb following mbuf n. If n
* is null, the buffer is presumed empty.
*/
static inline void
sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n)
{
int eor = 0, compress = (!(sb->sb_flags & SB_NOCOMPRESS));
struct mbuf *o;
if (m == NULL) {
/* There is nothing to compress; just update the tail */
for (; n->m_next != NULL; n = n->m_next) {
;
}
sb->sb_mbtail = n;
goto done;
}
while (m != NULL) {
eor |= m->m_flags & M_EOR;
if (compress && m->m_len == 0 && (eor == 0 ||
(((o = m->m_next) || (o = n)) && o->m_type == m->m_type))) {
if (sb->sb_lastrecord == m) {
sb->sb_lastrecord = m->m_next;
}
m = m_free(m);
continue;
}
if (compress && n != NULL && (n->m_flags & M_EOR) == 0 &&
#ifndef __APPLE__
M_WRITABLE(n) &&
#endif
m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */
m->m_len <= M_TRAILINGSPACE(n) &&
n->m_type == m->m_type) {
bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len,
(unsigned)m->m_len);
n->m_len += m->m_len;
sb->sb_cc += m->m_len;
if (!m_has_mtype(m, MTF_DATA | MTF_HEADER | MTF_OOBDATA)) {
/* XXX: Probably don't need */
sb->sb_ctl += m->m_len;
}
/* update send byte count */
if (sb->sb_flags & SB_SNDBYTE_CNT) {
inp_incr_sndbytes_total(sb->sb_so,
m->m_len);
inp_incr_sndbytes_unsent(sb->sb_so,
m->m_len);
}
m = m_free(m);
continue;
}
if (n != NULL) {
n->m_next = m;
} else {
sb->sb_mb = m;
}
sb->sb_mbtail = m;
sballoc(sb, m);
n = m;
m->m_flags &= ~M_EOR;
m = m->m_next;
n->m_next = NULL;
}
if (eor != 0) {
if (n != NULL) {
n->m_flags |= M_EOR;
} else {
printf("semi-panic: sbcompress\n");
}
}
done:
SBLASTMBUFCHK(sb, __func__);
}
void
sb_empty_assert(struct sockbuf *sb, const char *where)
{
if (!(sb->sb_cc == 0 && sb->sb_mb == NULL && sb->sb_mbcnt == 0 &&
sb->sb_mbtail == NULL && sb->sb_lastrecord == NULL)) {
panic("%s: sb %p so %p cc %d mbcnt %d mb %p mbtail %p "
"lastrecord %p\n", where, sb, sb->sb_so, sb->sb_cc,
sb->sb_mbcnt, sb->sb_mb, sb->sb_mbtail,
sb->sb_lastrecord);
/* NOTREACHED */
}
}
/*
* Free all mbufs in a sockbuf.
* Check that all resources are reclaimed.
*/
void
sbflush(struct sockbuf *sb)
{
void *lr_saved = __builtin_return_address(0);
struct socket *so = sb->sb_so;
/* so_usecount may be 0 if we get here from sofreelastref() */
if (so == NULL) {
panic("%s: null so, sb=%p sb_flags=0x%x lr=%p",
__func__, sb, sb->sb_flags, lr_saved);
/* NOTREACHED */
} else if (so->so_usecount < 0) {
panic("%s: sb=%p sb_flags=0x%x sb_so=%p usecount=%d lr=%p "
"lrh= %s\n", __func__, sb, sb->sb_flags, so,
so->so_usecount, lr_saved, solockhistory_nr(so));
/* NOTREACHED */
}
/*
* Obtain lock on the socket buffer (SB_LOCK). This is required
* to prevent the socket buffer from being unexpectedly altered
* while it is used by another thread in socket send/receive.
*
* sblock() must not fail here, hence the assertion.
*/
(void) sblock(sb, SBL_WAIT | SBL_NOINTR | SBL_IGNDEFUNCT);
VERIFY(sb->sb_flags & SB_LOCK);
while (sb->sb_mbcnt > 0) {
/*
* Don't call sbdrop(sb, 0) if the leading mbuf is non-empty:
* we would loop forever. Panic instead.
*/
if (!sb->sb_cc && (sb->sb_mb == NULL || sb->sb_mb->m_len)) {
break;
}
sbdrop(sb, (int)sb->sb_cc);
}
if (sb->sb_flags & SB_SENDHEAD) {
sb->sb_sendhead = NULL;
}
sb_empty_assert(sb, __func__);
sbunlock(sb, TRUE); /* keep socket locked */
}
/*
* Drop data from (the front of) a sockbuf.
* use m_freem_list to free the mbuf structures
* under a single lock... this is done by pruning
* the top of the tree from the body by keeping track
* of where we get to in the tree and then zeroing the
* two pertinent pointers m_nextpkt and m_next
* the socket buffer is then updated to point at the new
* top of the tree and the pruned area is released via
* m_freem_list.
*/
void
sbdrop(struct sockbuf *sb, int len)
{
struct mbuf *m, *free_list, *ml;
struct mbuf *next, *last;
next = (m = sb->sb_mb) ? m->m_nextpkt : 0;
#if MPTCP
if (m != NULL && len > 0 && !(sb->sb_flags & SB_RECV) &&
((sb->sb_so->so_flags & SOF_MP_SUBFLOW) ||
(SOCK_CHECK_DOM(sb->sb_so, PF_MULTIPATH) &&
SOCK_CHECK_PROTO(sb->sb_so, IPPROTO_TCP))) &&
!(sb->sb_so->so_flags1 & SOF1_POST_FALLBACK_SYNC)) {
mptcp_preproc_sbdrop(sb->sb_so, m, (unsigned int)len);
}
if (m != NULL && len > 0 && !(sb->sb_flags & SB_RECV) &&
(sb->sb_so->so_flags & SOF_MP_SUBFLOW) &&
(sb->sb_so->so_flags1 & SOF1_POST_FALLBACK_SYNC)) {
mptcp_fallback_sbdrop(sb->sb_so, m, len);
}
#endif /* MPTCP */
KERNEL_DEBUG((DBG_FNC_SBDROP | DBG_FUNC_START), sb, len, 0, 0, 0);
free_list = last = m;
ml = (struct mbuf *)0;
if (sb->sb_flags & SB_SENDHEAD) {
sb->sb_sendoff -= MIN(len, sb->sb_sendoff);
}
while (len > 0) {
if (m == NULL) {
if (next == NULL) {
/*
* temporarily replacing this panic with printf
* because it occurs occasionally when closing
* a socket when there is no harm in ignoring
* it. This problem will be investigated
* further.
*/
/* panic("sbdrop"); */
printf("sbdrop - count not zero\n");
len = 0;
/*
* zero the counts. if we have no mbufs,
* we have no data (PR-2986815)
*/
sb->sb_cc = 0;
sb->sb_mbcnt = 0;
break;
}
m = last = next;
next = m->m_nextpkt;
continue;
}
if (m->m_len > len) {
m->m_len -= len;
m->m_data += len;
sb->sb_cc -= len;
/* update the send byte count */
if (sb->sb_flags & SB_SNDBYTE_CNT) {
inp_decr_sndbytes_total(sb->sb_so, len);
}
if (sb->sb_flags & SB_SENDHEAD) {
if (sb->sb_sendhead == m) {
sb->sb_sendhead = NULL;
}
}
if (!m_has_mtype(m, MTF_DATA | MTF_HEADER | MTF_OOBDATA)) {
sb->sb_ctl -= len;
}
break;
}
len -= m->m_len;
sbfree(sb, m);
ml = m;
m = m->m_next;
}
while (m && m->m_len == 0) {
sbfree(sb, m);
ml = m;
m = m->m_next;
}
if (ml) {
ml->m_next = (struct mbuf *)0;
last->m_nextpkt = (struct mbuf *)0;
m_freem_list(free_list);
}
if (m) {
sb->sb_mb = m;
m->m_nextpkt = next;
} else {
sb->sb_mb = next;
}
/*
* First part is an inline SB_EMPTY_FIXUP(). Second part
* makes sure sb_lastrecord is up-to-date if we dropped
* part of the last record.
*/
m = sb->sb_mb;
if (m == NULL) {
sb->sb_mbtail = NULL;
sb->sb_lastrecord = NULL;
} else if (m->m_nextpkt == NULL) {
sb->sb_lastrecord = m;
}
#if CONTENT_FILTER
cfil_sock_buf_update(sb);
#endif /* CONTENT_FILTER */
KERNEL_DEBUG((DBG_FNC_SBDROP | DBG_FUNC_END), sb, 0, 0, 0, 0);
}
/*
* Drop a record off the front of a sockbuf
* and move the next record to the front.
*/
void
sbdroprecord(struct sockbuf *sb)
{
struct mbuf *m, *mn;
m = sb->sb_mb;
if (m) {
sb->sb_mb = m->m_nextpkt;
do {
sbfree(sb, m);
MFREE(m, mn);
m = mn;
} while (m);
}
SB_EMPTY_FIXUP(sb);
}
/*
* Create a "control" mbuf containing the specified data
* with the specified type for presentation on a socket buffer.
*/
struct mbuf *
sbcreatecontrol(caddr_t p, int size, int type, int level)
{
struct cmsghdr *cp;
struct mbuf *m;
if (CMSG_SPACE((u_int)size) > MLEN) {
return (struct mbuf *)NULL;
}
if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) {
return (struct mbuf *)NULL;
}
cp = mtod(m, struct cmsghdr *);
VERIFY(IS_P2ALIGNED(cp, sizeof(u_int32_t)));
/* XXX check size? */
(void) memcpy(CMSG_DATA(cp), p, size);
m->m_len = (int32_t)CMSG_SPACE(size);
cp->cmsg_len = CMSG_LEN(size);
cp->cmsg_level = level;
cp->cmsg_type = type;
return m;
}
struct mbuf **
sbcreatecontrol_mbuf(caddr_t p, int size, int type, int level, struct mbuf **mp)
{
struct mbuf *m;
struct cmsghdr *cp;
if (*mp == NULL) {
*mp = sbcreatecontrol(p, size, type, level);
return mp;
}
if (CMSG_SPACE((u_int)size) + (*mp)->m_len > MLEN) {
mp = &(*mp)->m_next;
*mp = sbcreatecontrol(p, size, type, level);
return mp;
}
m = *mp;
cp = (struct cmsghdr *)(void *)(mtod(m, char *) + m->m_len);
/* CMSG_SPACE ensures 32-bit alignment */
VERIFY(IS_P2ALIGNED(cp, sizeof(u_int32_t)));
m->m_len += (int32_t)CMSG_SPACE(size);
/* XXX check size? */
(void) memcpy(CMSG_DATA(cp), p, size);
cp->cmsg_len = CMSG_LEN(size);
cp->cmsg_level = level;
cp->cmsg_type = type;
return mp;
}
/*
* Some routines that return EOPNOTSUPP for entry points that are not
* supported by a protocol. Fill in as needed.
*/
int
pru_abort_notsupp(struct socket *so)
{
#pragma unused(so)
return EOPNOTSUPP;
}
int
pru_accept_notsupp(struct socket *so, struct sockaddr **nam)
{
#pragma unused(so, nam)
return EOPNOTSUPP;
}
int
pru_attach_notsupp(struct socket *so, int proto, struct proc *p)
{
#pragma unused(so, proto, p)
return EOPNOTSUPP;
}
int
pru_bind_notsupp(struct socket *so, struct sockaddr *nam, struct proc *p)
{
#pragma unused(so, nam, p)
return EOPNOTSUPP;
}
int
pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct proc *p)
{
#pragma unused(so, nam, p)
return EOPNOTSUPP;
}
int
pru_connect2_notsupp(struct socket *so1, struct socket *so2)
{
#pragma unused(so1, so2)
return EOPNOTSUPP;
}
int
pru_connectx_notsupp(struct socket *so, struct sockaddr *src,
struct sockaddr *dst, struct proc *p, uint32_t ifscope,
sae_associd_t aid, sae_connid_t *pcid, uint32_t flags, void *arg,
uint32_t arglen, struct uio *uio, user_ssize_t *bytes_written)
{
#pragma unused(so, src, dst, p, ifscope, aid, pcid, flags, arg, arglen, uio, bytes_written)
return EOPNOTSUPP;
}
int
pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data,
struct ifnet *ifp, struct proc *p)
{
#pragma unused(so, cmd, data, ifp, p)
return EOPNOTSUPP;
}
int
pru_detach_notsupp(struct socket *so)
{
#pragma unused(so)
return EOPNOTSUPP;
}
int
pru_disconnect_notsupp(struct socket *so)
{
#pragma unused(so)
return EOPNOTSUPP;
}
int
pru_disconnectx_notsupp(struct socket *so, sae_associd_t aid, sae_connid_t cid)
{
#pragma unused(so, aid, cid)
return EOPNOTSUPP;
}
int
pru_listen_notsupp(struct socket *so, struct proc *p)
{
#pragma unused(so, p)
return EOPNOTSUPP;
}
int
pru_peeraddr_notsupp(struct socket *so, struct sockaddr **nam)
{
#pragma unused(so, nam)
return EOPNOTSUPP;
}
int
pru_rcvd_notsupp(struct socket *so, int flags)
{
#pragma unused(so, flags)
return EOPNOTSUPP;
}
int
pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags)
{
#pragma unused(so, m, flags)
return EOPNOTSUPP;
}
int
pru_send_notsupp(struct socket *so, int flags, struct mbuf *m,
struct sockaddr *addr, struct mbuf *control, struct proc *p)
{
#pragma unused(so, flags, m, addr, control, p)
return EOPNOTSUPP;
}
int
pru_send_list_notsupp(struct socket *so, struct mbuf *m, u_int *pktcnt,
int flags)
{
#pragma unused(so, m, pktcnt, flags)
return EOPNOTSUPP;
}
/*
* This isn't really a ``null'' operation, but it's the default one
* and doesn't do anything destructive.
*/
int
pru_sense_null(struct socket *so, void *ub, int isstat64)
{
if (isstat64 != 0) {
struct stat64 *sb64;
sb64 = (struct stat64 *)ub;
sb64->st_blksize = so->so_snd.sb_hiwat;
} else {
struct stat *sb;
sb = (struct stat *)ub;
sb->st_blksize = so->so_snd.sb_hiwat;
}
return 0;
}
int
pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio,
struct mbuf *top, struct mbuf *control, int flags)
{
#pragma unused(so, addr, uio, top, control, flags)
return EOPNOTSUPP;
}
int
pru_sosend_list_notsupp(struct socket *so, struct mbuf *m, size_t total_len, u_int *pktcnt, int flags)
{
#pragma unused(so, m, total_len, pktcnt, flags)
return EOPNOTSUPP;
}
int
pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr,
struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
{
#pragma unused(so, paddr, uio, mp0, controlp, flagsp)
return EOPNOTSUPP;
}
int
pru_shutdown_notsupp(struct socket *so)
{
#pragma unused(so)
return EOPNOTSUPP;
}
int
pru_sockaddr_notsupp(struct socket *so, struct sockaddr **nam)
{
#pragma unused(so, nam)
return EOPNOTSUPP;
}
int
pru_sopoll_notsupp(struct socket *so, int events, kauth_cred_t cred, void *wql)
{
#pragma unused(so, events, cred, wql)
return EOPNOTSUPP;
}
int
pru_socheckopt_null(struct socket *so, struct sockopt *sopt)
{
#pragma unused(so, sopt)
/*
* Allow all options for set/get by default.
*/
return 0;
}
static int
pru_preconnect_null(struct socket *so)
{
#pragma unused(so)
return 0;
}
static int
pru_defunct_null(struct socket *so)
{
#pragma unused(so)
return 0;
}
void
pru_sanitize(struct pr_usrreqs *pru)
{
#define DEFAULT(foo, bar) if ((foo) == NULL) (foo) = (bar)
DEFAULT(pru->pru_abort, pru_abort_notsupp);
DEFAULT(pru->pru_accept, pru_accept_notsupp);
DEFAULT(pru->pru_attach, pru_attach_notsupp);
DEFAULT(pru->pru_bind, pru_bind_notsupp);
DEFAULT(pru->pru_connect, pru_connect_notsupp);
DEFAULT(pru->pru_connect2, pru_connect2_notsupp);
DEFAULT(pru->pru_connectx, pru_connectx_notsupp);
DEFAULT(pru->pru_control, pru_control_notsupp);
DEFAULT(pru->pru_detach, pru_detach_notsupp);
DEFAULT(pru->pru_disconnect, pru_disconnect_notsupp);
DEFAULT(pru->pru_disconnectx, pru_disconnectx_notsupp);
DEFAULT(pru->pru_listen, pru_listen_notsupp);
DEFAULT(pru->pru_peeraddr, pru_peeraddr_notsupp);
DEFAULT(pru->pru_rcvd, pru_rcvd_notsupp);
DEFAULT(pru->pru_rcvoob, pru_rcvoob_notsupp);
DEFAULT(pru->pru_send, pru_send_notsupp);
DEFAULT(pru->pru_send_list, pru_send_list_notsupp);
DEFAULT(pru->pru_sense, pru_sense_null);
DEFAULT(pru->pru_shutdown, pru_shutdown_notsupp);
DEFAULT(pru->pru_sockaddr, pru_sockaddr_notsupp);
DEFAULT(pru->pru_sopoll, pru_sopoll_notsupp);
DEFAULT(pru->pru_soreceive, pru_soreceive_notsupp);
DEFAULT(pru->pru_sosend, pru_sosend_notsupp);
DEFAULT(pru->pru_sosend_list, pru_sosend_list_notsupp);
DEFAULT(pru->pru_socheckopt, pru_socheckopt_null);
DEFAULT(pru->pru_preconnect, pru_preconnect_null);
DEFAULT(pru->pru_defunct, pru_defunct_null);
#undef DEFAULT
}
/*
* The following are macros on BSD and functions on Darwin
*/
/*
* Do we need to notify the other side when I/O is possible?
*/
int
sb_notify(struct sockbuf *sb)
{
return sb->sb_waiters > 0 ||
(sb->sb_flags & (SB_SEL | SB_ASYNC | SB_UPCALL | SB_KNOTE));
}
/*
* How much space is there in a socket buffer (so->so_snd or so->so_rcv)?
* This is problematical if the fields are unsigned, as the space might
* still be negative (cc > hiwat or mbcnt > mbmax). Should detect
* overflow and return 0.
*/
int
sbspace(struct sockbuf *sb)
{
int pending = 0;
int space;
if (sb->sb_flags & SB_KCTL) {
space = (int)(sb->sb_hiwat - sb->sb_cc);
} else {
space = imin((int)(sb->sb_hiwat - sb->sb_cc),
(int)(sb->sb_mbmax - sb->sb_mbcnt));
}
if (sb->sb_preconn_hiwat != 0) {
space = imin((int)(sb->sb_preconn_hiwat - sb->sb_cc), space);
}
if (space < 0) {
space = 0;
}
/* Compensate for data being processed by content filters */
#if CONTENT_FILTER
pending = cfil_sock_data_space(sb);
#endif /* CONTENT_FILTER */
if (pending > space) {
space = 0;
} else {
space -= pending;
}
return space;
}
/* do we have to send all at once on a socket? */
int
sosendallatonce(struct socket *so)
{
return so->so_proto->pr_flags & PR_ATOMIC;
}
/* can we read something from so? */
int
soreadable(struct socket *so)
{
return so->so_rcv.sb_cc >= so->so_rcv.sb_lowat ||
((so->so_state & SS_CANTRCVMORE)
#if CONTENT_FILTER
&& cfil_sock_data_pending(&so->so_rcv) == 0
#endif /* CONTENT_FILTER */
) ||
so->so_comp.tqh_first || so->so_error;
}
/* can we write something to so? */
int
sowriteable(struct socket *so)
{
if ((so->so_state & SS_CANTSENDMORE) ||
so->so_error > 0) {
return 1;
}
if (so_wait_for_if_feedback(so) || !socanwrite(so)) {
return 0;
}
if (so->so_flags1 & SOF1_PRECONNECT_DATA) {
return 1;
}
int64_t data = sbspace(&so->so_snd);
int64_t lowat = so->so_snd.sb_lowat;
/*
* Deal with connected UNIX domain sockets which
* rely on the fact that the sender's socket buffer is
* actually the receiver's socket buffer.
*/
if (SOCK_DOM(so) == PF_LOCAL) {
struct unpcb *unp = sotounpcb(so);
if (unp != NULL && unp->unp_conn != NULL &&
unp->unp_conn->unp_socket != NULL) {
struct socket *so2 = unp->unp_conn->unp_socket;
/*
* At this point we know that `so' is locked
* and that `unp_conn` isn't going to change.
* However, we don't lock `so2` because doing so
* may require unlocking `so'
* (see unp_get_locks_in_order()).
*
* Two cases can happen:
*
* 1) we return 1 and tell the application that
* it can write. Meanwhile, another thread
* fills up the socket buffer. This will either
* lead to a blocking send or EWOULDBLOCK
* which the application should deal with.
* 2) we return 0 and tell the application that
* the socket is not writable. Meanwhile,
* another thread depletes the receive socket
* buffer. In this case the application will
* be woken up by sb_notify().
*
* MIN() is required because otherwise sosendcheck()
* may return EWOULDBLOCK since it only considers
* so->so_snd.
*/
data = MIN(data, sbspace(&so2->so_rcv));
}
}
if (data >= lowat) {
if (so->so_flags & SOF_NOTSENT_LOWAT) {
if ((SOCK_DOM(so) == PF_INET6 ||
SOCK_DOM(so) == PF_INET) &&
so->so_type == SOCK_STREAM) {
return tcp_notsent_lowat_check(so);
}
#if MPTCP
else if ((SOCK_DOM(so) == PF_MULTIPATH) &&
(SOCK_PROTO(so) == IPPROTO_TCP)) {
return mptcp_notsent_lowat_check(so);
}
#endif
else {
return 1;
}
} else {
return 1;
}
}
return 0;
}
/* adjust counters in sb reflecting allocation of m */
void
sballoc(struct sockbuf *sb, struct mbuf *m)
{
sb->sb_cc += m->m_len;
if (!m_has_mtype(m, MTF_DATA | MTF_HEADER | MTF_OOBDATA)) {
sb->sb_ctl += m->m_len;
}
sb->sb_mbcnt += _MSIZE;
if (m->m_flags & M_EXT) {
sb->sb_mbcnt += m->m_ext.ext_size;
}
/*
* If data is being added to the send socket buffer,
* update the send byte count
*/
if (sb->sb_flags & SB_SNDBYTE_CNT) {
inp_incr_sndbytes_total(sb->sb_so, m->m_len);
inp_incr_sndbytes_unsent(sb->sb_so, m->m_len);
}
}
/* adjust counters in sb reflecting freeing of m */
void
sbfree(struct sockbuf *sb, struct mbuf *m)
{
sb->sb_cc -= m->m_len;
if (!m_has_mtype(m, MTF_DATA | MTF_HEADER | MTF_OOBDATA)) {
sb->sb_ctl -= m->m_len;
}
sb->sb_mbcnt -= _MSIZE;
if (m->m_flags & M_EXT) {
sb->sb_mbcnt -= m->m_ext.ext_size;
}
/*
* If data is being removed from the send socket buffer,
* update the send byte count
*/
if (sb->sb_flags & SB_SNDBYTE_CNT) {
inp_decr_sndbytes_total(sb->sb_so, m->m_len);
}
if (sb->sb_flags & SB_SENDHEAD) {
if (m == sb->sb_sendhead) {
sb->sb_sendhead = NULL;
}
}
}
/*
* Set lock on sockbuf sb; sleep if lock is already held.
* Unless SB_NOINTR is set on sockbuf, sleep is interruptible.
* Returns error without lock if sleep is interrupted.
*/
int
sblock(struct sockbuf *sb, uint32_t flags)
{
boolean_t nointr = ((sb->sb_flags & SB_NOINTR) || (flags & SBL_NOINTR));
void *lr_saved = __builtin_return_address(0);
struct socket *so = sb->sb_so;
void * wchan;
int error = 0;
thread_t tp = current_thread();
VERIFY((flags & SBL_VALID) == flags);
/* so_usecount may be 0 if we get here from sofreelastref() */
if (so == NULL) {
panic("%s: null so, sb=%p sb_flags=0x%x lr=%p",
__func__, sb, sb->sb_flags, lr_saved);
/* NOTREACHED */
} else if (so->so_usecount < 0) {
panic("%s: sb=%p sb_flags=0x%x sb_so=%p usecount=%d lr=%p "
"lrh= %s\n", __func__, sb, sb->sb_flags, so,
so->so_usecount, lr_saved, solockhistory_nr(so));
/* NOTREACHED */
}
/*
* The content filter thread must hold the sockbuf lock
*/
if ((so->so_flags & SOF_CONTENT_FILTER) && sb->sb_cfil_thread == tp) {
/*
* Don't panic if we are defunct because SB_LOCK has
* been cleared by sodefunct()
*/
if (!(so->so_flags & SOF_DEFUNCT) && !(sb->sb_flags & SB_LOCK)) {
panic("%s: SB_LOCK not held for %p",
__func__, sb);
}
/* Keep the sockbuf locked */
return 0;
}
if ((sb->sb_flags & SB_LOCK) && !(flags & SBL_WAIT)) {
return EWOULDBLOCK;
}
/*
* We may get here from sorflush(), in which case "sb" may not
* point to the real socket buffer. Use the actual socket buffer
* address from the socket instead.
*/
wchan = (sb->sb_flags & SB_RECV) ?
&so->so_rcv.sb_flags : &so->so_snd.sb_flags;
/*
* A content filter thread has exclusive access to the sockbuf
* until it clears the
*/
while ((sb->sb_flags & SB_LOCK) ||
((so->so_flags & SOF_CONTENT_FILTER) &&
sb->sb_cfil_thread != NULL)) {
lck_mtx_t *mutex_held;
/*
* XXX: This code should be moved up above outside of this loop;
* however, we may get here as part of sofreelastref(), and
* at that time pr_getlock() may no longer be able to return
* us the lock. This will be fixed in future.
*/
if (so->so_proto->pr_getlock != NULL) {
mutex_held = (*so->so_proto->pr_getlock)(so, PR_F_WILLUNLOCK);
} else {
mutex_held = so->so_proto->pr_domain->dom_mtx;
}
LCK_MTX_ASSERT(mutex_held, LCK_MTX_ASSERT_OWNED);
sb->sb_wantlock++;
VERIFY(sb->sb_wantlock != 0);
error = msleep(wchan, mutex_held,
nointr ? PSOCK : PSOCK | PCATCH,
nointr ? "sb_lock_nointr" : "sb_lock", NULL);
VERIFY(sb->sb_wantlock != 0);
sb->sb_wantlock--;
if (error == 0 && (so->so_flags & SOF_DEFUNCT) &&
!(flags & SBL_IGNDEFUNCT)) {
error = EBADF;
SODEFUNCTLOG("%s[%d, %s]: defunct so 0x%llu [%d,%d] "
"(%d)\n", __func__, proc_selfpid(),
proc_best_name(current_proc()),
so->so_gencnt,
SOCK_DOM(so), SOCK_TYPE(so), error);
}
if (error != 0) {
return error;
}
}
sb->sb_flags |= SB_LOCK;
return 0;
}
/*
* Release lock on sockbuf sb
*/
void
sbunlock(struct sockbuf *sb, boolean_t keeplocked)
{
void *lr_saved = __builtin_return_address(0);
struct socket *so = sb->sb_so;
thread_t tp = current_thread();
/* so_usecount may be 0 if we get here from sofreelastref() */
if (so == NULL) {
panic("%s: null so, sb=%p sb_flags=0x%x lr=%p",
__func__, sb, sb->sb_flags, lr_saved);
/* NOTREACHED */
} else if (so->so_usecount < 0) {
panic("%s: sb=%p sb_flags=0x%x sb_so=%p usecount=%d lr=%p "
"lrh= %s\n", __func__, sb, sb->sb_flags, so,
so->so_usecount, lr_saved, solockhistory_nr(so));
/* NOTREACHED */
}
/*
* The content filter thread must hold the sockbuf lock
*/
if ((so->so_flags & SOF_CONTENT_FILTER) && sb->sb_cfil_thread == tp) {
/*
* Don't panic if we are defunct because SB_LOCK has
* been cleared by sodefunct()
*/
if (!(so->so_flags & SOF_DEFUNCT) &&
!(sb->sb_flags & SB_LOCK) &&
!(so->so_state & SS_DEFUNCT) &&
!(so->so_flags1 & SOF1_DEFUNCTINPROG)) {
panic("%s: SB_LOCK not held for %p",
__func__, sb);
}
/* Keep the sockbuf locked and proceed */
} else {
VERIFY((sb->sb_flags & SB_LOCK) ||
(so->so_state & SS_DEFUNCT) ||
(so->so_flags1 & SOF1_DEFUNCTINPROG));
sb->sb_flags &= ~SB_LOCK;
if (sb->sb_wantlock > 0) {
/*
* We may get here from sorflush(), in which case "sb"
* may not point to the real socket buffer. Use the
* actual socket buffer address from the socket instead.
*/
wakeup((sb->sb_flags & SB_RECV) ? &so->so_rcv.sb_flags :
&so->so_snd.sb_flags);
}
}
if (!keeplocked) { /* unlock on exit */
if (so->so_flags & SOF_MP_SUBFLOW || SOCK_DOM(so) == PF_MULTIPATH) {
(*so->so_proto->pr_unlock)(so, 1, lr_saved);
} else {
lck_mtx_t *mutex_held;
if (so->so_proto->pr_getlock != NULL) {
mutex_held = (*so->so_proto->pr_getlock)(so, PR_F_WILLUNLOCK);
} else {
mutex_held = so->so_proto->pr_domain->dom_mtx;
}
LCK_MTX_ASSERT(mutex_held, LCK_MTX_ASSERT_OWNED);
VERIFY(so->so_usecount > 0);
so->so_usecount--;
so->unlock_lr[so->next_unlock_lr] = lr_saved;
so->next_unlock_lr = (so->next_unlock_lr + 1) % SO_LCKDBG_MAX;
lck_mtx_unlock(mutex_held);
}
}
}
void
sorwakeup(struct socket *so)
{
if (sb_notify(&so->so_rcv)) {
sowakeup(so, &so->so_rcv, NULL);
}
}
void
sowwakeup(struct socket *so)
{
if (sb_notify(&so->so_snd)) {
sowakeup(so, &so->so_snd, NULL);
}
}
static void
soevupcall(struct socket *so, uint32_t hint)
{
if (so->so_event != NULL) {
caddr_t so_eventarg = so->so_eventarg;
hint &= so->so_eventmask;
if (hint != 0) {
so->so_event(so, so_eventarg, hint);
}
}
}
void
soevent(struct socket *so, uint32_t hint)
{
if (net_wake_pkt_debug > 0 && (hint & SO_FILT_HINT_WAKE_PKT)) {
os_log(OS_LOG_DEFAULT, "%s: SO_FILT_HINT_WAKE_PKT so %p",
__func__, so);
}
if (so->so_flags & SOF_KNOTE) {
KNOTE(&so->so_klist, hint);
}
soevupcall(so, hint);
/*
* Don't post an event if this a subflow socket or
* the app has opted out of using cellular interface
*/
if ((hint & SO_FILT_HINT_IFDENIED) &&
!(so->so_flags & SOF_MP_SUBFLOW) &&
!(so->so_restrictions & SO_RESTRICT_DENY_CELLULAR) &&
!(so->so_restrictions & SO_RESTRICT_DENY_EXPENSIVE) &&
!(so->so_restrictions & SO_RESTRICT_DENY_CONSTRAINED)) {
soevent_ifdenied(so);
}
}
static void
soevent_ifdenied(struct socket *so)
{
struct kev_netpolicy_ifdenied ev_ifdenied;
bzero(&ev_ifdenied, sizeof(ev_ifdenied));
/*
* The event consumer is interested about the effective {upid,pid,uuid}
* info which can be different than the those related to the process
* that recently performed a system call on the socket, i.e. when the
* socket is delegated.
*/
if (so->so_flags & SOF_DELEGATED) {
ev_ifdenied.ev_data.eupid = so->e_upid;
ev_ifdenied.ev_data.epid = so->e_pid;
uuid_copy(ev_ifdenied.ev_data.euuid, so->e_uuid);
} else {
ev_ifdenied.ev_data.eupid = so->last_upid;
ev_ifdenied.ev_data.epid = so->last_pid;
uuid_copy(ev_ifdenied.ev_data.euuid, so->last_uuid);
}
if (++so->so_ifdenied_notifies > 1) {
/*
* Allow for at most one kernel event to be generated per
* socket; so_ifdenied_notifies is reset upon changes in
* the UUID policy. See comments in inp_update_policy.
*/
if (net_io_policy_log) {
uuid_string_t buf;
uuid_unparse(ev_ifdenied.ev_data.euuid, buf);
log(LOG_DEBUG, "%s[%d]: so 0x%llx [%d,%d] epid %llu "
"euuid %s%s has %d redundant events supressed\n",
__func__, so->last_pid,
(uint64_t)VM_KERNEL_ADDRPERM(so), SOCK_DOM(so),
SOCK_TYPE(so), ev_ifdenied.ev_data.epid, buf,
((so->so_flags & SOF_DELEGATED) ?
" [delegated]" : ""), so->so_ifdenied_notifies);
}
} else {
if (net_io_policy_log) {
uuid_string_t buf;
uuid_unparse(ev_ifdenied.ev_data.euuid, buf);
log(LOG_DEBUG, "%s[%d]: so 0x%llx [%d,%d] epid %llu "
"euuid %s%s event posted\n", __func__,
so->last_pid, (uint64_t)VM_KERNEL_ADDRPERM(so),
SOCK_DOM(so), SOCK_TYPE(so),
ev_ifdenied.ev_data.epid, buf,
((so->so_flags & SOF_DELEGATED) ?
" [delegated]" : ""));
}
netpolicy_post_msg(KEV_NETPOLICY_IFDENIED, &ev_ifdenied.ev_data,
sizeof(ev_ifdenied));
}
}
/*
* Make a copy of a sockaddr in a malloced buffer of type SONAME.
*/
struct sockaddr *
dup_sockaddr(struct sockaddr *sa, int canwait)
{
struct sockaddr *sa2;
sa2 = SA(alloc_sockaddr(sa->sa_len, canwait ? Z_WAITOK : Z_NOWAIT));
if (sa2 != NULL) {
SOCKADDR_COPY(sa, sa2, sa->sa_len);
}
return sa2;
}
void * __header_indexable
alloc_sockaddr(size_t size, zalloc_flags_t flags)
{
VERIFY((size) <= UINT8_MAX);
__typed_allocators_ignore_push
void * buf = kheap_alloc(KHEAP_SONAME, size, flags | Z_ZERO);
__typed_allocators_ignore_pop
if (buf != NULL) {
struct sockaddr *sa = SA(buf);
sa->sa_len = (uint8_t)size;
}
return buf;
}
/*
* Create an external-format (``xsocket'') structure using the information
* in the kernel-format socket structure pointed to by so. This is done
* to reduce the spew of irrelevant information over this interface,
* to isolate user code from changes in the kernel structure, and
* potentially to provide information-hiding if we decide that
* some of this information should be hidden from users.
*/
void
sotoxsocket(struct socket *so, struct xsocket *xso)
{
xso->xso_len = sizeof(*xso);
xso->xso_so = (_XSOCKET_PTR(struct socket *))VM_KERNEL_ADDRPERM(so);
xso->so_type = so->so_type;
xso->so_options = (short)(so->so_options & 0xffff);
xso->so_linger = so->so_linger;
xso->so_state = so->so_state;
xso->so_pcb = (_XSOCKET_PTR(caddr_t))VM_KERNEL_ADDRPERM(so->so_pcb);
if (so->so_proto) {
xso->xso_protocol = SOCK_PROTO(so);
xso->xso_family = SOCK_DOM(so);
} else {
xso->xso_protocol = xso->xso_family = 0;
}
xso->so_qlen = so->so_qlen;
xso->so_incqlen = so->so_incqlen;
xso->so_qlimit = so->so_qlimit;
xso->so_timeo = so->so_timeo;
xso->so_error = so->so_error;
xso->so_pgid = so->so_pgid;
xso->so_oobmark = so->so_oobmark;
sbtoxsockbuf(&so->so_snd, &xso->so_snd);
sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
xso->so_uid = kauth_cred_getuid(so->so_cred);
}
#if XNU_TARGET_OS_OSX
void
sotoxsocket64(struct socket *so, struct xsocket64 *xso)
{
xso->xso_len = sizeof(*xso);
xso->xso_so = (u_int64_t)VM_KERNEL_ADDRPERM(so);
xso->so_type = so->so_type;
xso->so_options = (short)(so->so_options & 0xffff);
xso->so_linger = so->so_linger;
xso->so_state = so->so_state;
xso->so_pcb = (u_int64_t)VM_KERNEL_ADDRPERM(so->so_pcb);
if (so->so_proto) {
xso->xso_protocol = SOCK_PROTO(so);
xso->xso_family = SOCK_DOM(so);
} else {
xso->xso_protocol = xso->xso_family = 0;
}
xso->so_qlen = so->so_qlen;
xso->so_incqlen = so->so_incqlen;
xso->so_qlimit = so->so_qlimit;
xso->so_timeo = so->so_timeo;
xso->so_error = so->so_error;
xso->so_pgid = so->so_pgid;
xso->so_oobmark = so->so_oobmark;
sbtoxsockbuf(&so->so_snd, &xso->so_snd);
sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
xso->so_uid = kauth_cred_getuid(so->so_cred);
}
#endif /* XNU_TARGET_OS_OSX */
/*
* This does the same for sockbufs. Note that the xsockbuf structure,
* since it is always embedded in a socket, does not include a self
* pointer nor a length. We make this entry point public in case
* some other mechanism needs it.
*/
void
sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb)
{
xsb->sb_cc = sb->sb_cc;
xsb->sb_hiwat = sb->sb_hiwat;
xsb->sb_mbcnt = sb->sb_mbcnt;
xsb->sb_mbmax = sb->sb_mbmax;
xsb->sb_lowat = sb->sb_lowat;
xsb->sb_flags = (short)sb->sb_flags;
xsb->sb_timeo = (short)
((sb->sb_timeo.tv_sec * hz) + sb->sb_timeo.tv_usec / tick);
if (xsb->sb_timeo == 0 && sb->sb_timeo.tv_usec != 0) {
xsb->sb_timeo = 1;
}
}
/*
* Based on the policy set by an all knowing decison maker, throttle sockets
* that either have been marked as belonging to "background" process.
*/
inline int
soisthrottled(struct socket *so)
{
return so->so_flags1 & SOF1_TRAFFIC_MGT_SO_BACKGROUND;
}
inline int
soisprivilegedtraffic(struct socket *so)
{
return (so->so_flags & SOF_PRIVILEGED_TRAFFIC_CLASS) ? 1 : 0;
}
inline int
soissrcbackground(struct socket *so)
{
return (so->so_flags1 & SOF1_TRAFFIC_MGT_SO_BACKGROUND) ||
IS_SO_TC_BACKGROUND(so->so_traffic_class);
}
inline int
soissrcrealtime(struct socket *so)
{
return so->so_traffic_class >= SO_TC_AV &&
so->so_traffic_class <= SO_TC_VO;
}
inline int
soissrcbesteffort(struct socket *so)
{
return so->so_traffic_class == SO_TC_BE ||
so->so_traffic_class == SO_TC_RD ||
so->so_traffic_class == SO_TC_OAM;
}
void
soclearfastopen(struct socket *so)
{
if (so->so_flags1 & SOF1_PRECONNECT_DATA) {
so->so_flags1 &= ~SOF1_PRECONNECT_DATA;
}
if (so->so_flags1 & SOF1_DATA_IDEMPOTENT) {
so->so_flags1 &= ~SOF1_DATA_IDEMPOTENT;
}
}
void
sonullevent(struct socket *so, void *arg, uint32_t hint)
{
#pragma unused(so, arg, hint)
}
/*
* Here is the definition of some of the basic objects in the kern.ipc
* branch of the MIB.
*/
SYSCTL_NODE(_kern, KERN_IPC, ipc,
CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_ANYBODY, 0, "IPC");
/* Check that the maximum socket buffer size is within a range */
static int
sysctl_sb_max SYSCTL_HANDLER_ARGS
{
#pragma unused(oidp, arg1, arg2)
u_int32_t new_value;
int changed = 0;
int error = sysctl_io_number(req, sb_max, sizeof(u_int32_t),
&new_value, &changed);
if (!error && changed) {
if (new_value > LOW_SB_MAX && new_value <= high_sb_max) {
sb_max = new_value;
} else {
error = ERANGE;
}
}
return error;
}
SYSCTL_PROC(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
&sb_max, 0, &sysctl_sb_max, "IU", "Maximum socket buffer size");
SYSCTL_INT(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor,
CTLFLAG_RW | CTLFLAG_LOCKED, &sb_efficiency, 0, "");
SYSCTL_INT(_kern_ipc, KIPC_NMBCLUSTERS, nmbclusters,
CTLFLAG_RD | CTLFLAG_LOCKED, &nmbclusters, 0, "");
SYSCTL_INT(_kern_ipc, OID_AUTO, njcl,
CTLFLAG_RD | CTLFLAG_LOCKED, &njcl, 0, "");
SYSCTL_INT(_kern_ipc, OID_AUTO, njclbytes,
CTLFLAG_RD | CTLFLAG_LOCKED, &njclbytes, 0, "");
SYSCTL_INT(_kern_ipc, KIPC_SOQLIMITCOMPAT, soqlimitcompat,
CTLFLAG_RW | CTLFLAG_LOCKED, &soqlimitcompat, 1,
"Enable socket queue limit compatibility");
/*
* Hack alert -- rdar://33572856
* A loopback test we cannot change was failing because it sets
* SO_SENDTIMEO to 5 seconds and that's also the value
* of the minimum persist timer. Because of the persist timer,
* the connection was not idle for 5 seconds and SO_SNDTIMEO
* was not triggering at 5 seconds causing the test failure.
* As a workaround we check the sysctl soqlencomp the test is already
* setting to set disable auto tuning of the receive buffer.
*/
extern u_int32_t tcp_do_autorcvbuf;
static int
sysctl_soqlencomp SYSCTL_HANDLER_ARGS
{
#pragma unused(oidp, arg1, arg2)
u_int32_t new_value;
int changed = 0;
int error = sysctl_io_number(req, soqlencomp, sizeof(u_int32_t),
&new_value, &changed);
if (!error && changed) {
soqlencomp = new_value;
if (new_value != 0) {
tcp_do_autorcvbuf = 0;
tcptv_persmin_val = 6 * TCP_RETRANSHZ;
}
}
return error;
}
SYSCTL_PROC(_kern_ipc, OID_AUTO, soqlencomp,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
&soqlencomp, 0, &sysctl_soqlencomp, "IU", "");
SYSCTL_NODE(_kern_ipc, OID_AUTO, io_policy, CTLFLAG_RW, 0, "network IO policy");
SYSCTL_INT(_kern_ipc_io_policy, OID_AUTO, log, CTLFLAG_RW | CTLFLAG_LOCKED,
&net_io_policy_log, 0, "");
#if CONFIG_PROC_UUID_POLICY
SYSCTL_INT(_kern_ipc_io_policy, OID_AUTO, uuid, CTLFLAG_RW | CTLFLAG_LOCKED,
&net_io_policy_uuid, 0, "");
#endif /* CONFIG_PROC_UUID_POLICY */
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