freebsd-dev/sys/netipsec/keysock.c
Roy Marples 7045b1603b socket: Implement SO_RERROR
SO_RERROR indicates that receive buffer overflows should be handled as
errors. Historically receive buffer overflows have been ignored and
programs could not tell if they missed messages or messages had been
truncated because of overflows. Since programs historically do not
expect to get receive overflow errors, this behavior is not the
default.

This is really really important for programs that use route(4) to keep
in sync with the system. If we loose a message then we need to reload
the full system state, otherwise the behaviour from that point is
undefined and can lead to chasing bogus bug reports.

Reviewed by:	philip (network), kbowling (transport), gbe (manpages)
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D26652
2021-07-28 09:35:09 -07:00

476 lines
10 KiB
C

/* $FreeBSD$ */
/* $KAME: keysock.c,v 1.25 2001/08/13 20:07:41 itojun Exp $ */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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 project 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 PROJECT 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 PROJECT 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.
*/
#include "opt_ipsec.h"
/* This code has derived from sys/net/rtsock.c on FreeBSD2.2.5 */
#include <sys/types.h>
#include <sys/param.h>
#include <sys/domain.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/priv.h>
#include <sys/protosw.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <net/if.h>
#include <net/vnet.h>
#include <net/raw_cb.h>
#include <netinet/in.h>
#include <net/pfkeyv2.h>
#include <netipsec/key.h>
#include <netipsec/keysock.h>
#include <netipsec/key_debug.h>
#include <netipsec/ipsec.h>
#include <machine/stdarg.h>
struct key_cb {
int key_count;
int any_count;
};
VNET_DEFINE_STATIC(struct key_cb, key_cb);
#define V_key_cb VNET(key_cb)
static struct sockaddr key_src = { 2, PF_KEY, };
static int key_sendup0(struct rawcb *, struct mbuf *, int);
VNET_PCPUSTAT_DEFINE(struct pfkeystat, pfkeystat);
VNET_PCPUSTAT_SYSINIT(pfkeystat);
#ifdef VIMAGE
VNET_PCPUSTAT_SYSUNINIT(pfkeystat);
#endif /* VIMAGE */
/*
* key_output()
*/
int
key_output(struct mbuf *m, struct socket *so, ...)
{
struct sadb_msg *msg;
int len, error = 0;
if (m == NULL)
panic("%s: NULL pointer was passed.\n", __func__);
PFKEYSTAT_INC(out_total);
PFKEYSTAT_ADD(out_bytes, m->m_pkthdr.len);
len = m->m_pkthdr.len;
if (len < sizeof(struct sadb_msg)) {
PFKEYSTAT_INC(out_tooshort);
error = EINVAL;
goto end;
}
if (m->m_len < sizeof(struct sadb_msg)) {
if ((m = m_pullup(m, sizeof(struct sadb_msg))) == NULL) {
PFKEYSTAT_INC(out_nomem);
error = ENOBUFS;
goto end;
}
}
M_ASSERTPKTHDR(m);
KEYDBG(KEY_DUMP, kdebug_mbuf(m));
msg = mtod(m, struct sadb_msg *);
PFKEYSTAT_INC(out_msgtype[msg->sadb_msg_type]);
if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
PFKEYSTAT_INC(out_invlen);
error = EINVAL;
goto end;
}
error = key_parse(m, so);
m = NULL;
end:
if (m)
m_freem(m);
return error;
}
/*
* send message to the socket.
*/
static int
key_sendup0(struct rawcb *rp, struct mbuf *m, int promisc)
{
if (promisc) {
struct sadb_msg *pmsg;
M_PREPEND(m, sizeof(struct sadb_msg), M_NOWAIT);
if (m == NULL) {
PFKEYSTAT_INC(in_nomem);
return (ENOBUFS);
}
pmsg = mtod(m, struct sadb_msg *);
bzero(pmsg, sizeof(*pmsg));
pmsg->sadb_msg_version = PF_KEY_V2;
pmsg->sadb_msg_type = SADB_X_PROMISC;
pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
/* pid and seq? */
PFKEYSTAT_INC(in_msgtype[pmsg->sadb_msg_type]);
}
if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&key_src,
m, NULL)) {
PFKEYSTAT_INC(in_nomem);
m_freem(m);
soroverflow(rp->rcb_socket);
return ENOBUFS;
}
sorwakeup(rp->rcb_socket);
return 0;
}
/* so can be NULL if target != KEY_SENDUP_ONE */
int
key_sendup_mbuf(struct socket *so, struct mbuf *m, int target)
{
struct mbuf *n;
struct keycb *kp;
struct rawcb *rp;
int error = 0;
KASSERT(m != NULL, ("NULL mbuf pointer was passed."));
KASSERT(so != NULL || target != KEY_SENDUP_ONE,
("NULL socket pointer was passed."));
KASSERT(target == KEY_SENDUP_ONE || target == KEY_SENDUP_ALL ||
target == KEY_SENDUP_REGISTERED, ("Wrong target %d", target));
PFKEYSTAT_INC(in_total);
PFKEYSTAT_ADD(in_bytes, m->m_pkthdr.len);
if (m->m_len < sizeof(struct sadb_msg)) {
m = m_pullup(m, sizeof(struct sadb_msg));
if (m == NULL) {
PFKEYSTAT_INC(in_nomem);
return ENOBUFS;
}
}
if (m->m_len >= sizeof(struct sadb_msg)) {
struct sadb_msg *msg;
msg = mtod(m, struct sadb_msg *);
PFKEYSTAT_INC(in_msgtype[msg->sadb_msg_type]);
}
mtx_lock(&rawcb_mtx);
if (V_key_cb.any_count == 0) {
mtx_unlock(&rawcb_mtx);
m_freem(m);
return (0);
}
LIST_FOREACH(rp, &V_rawcb_list, list)
{
if (rp->rcb_proto.sp_family != PF_KEY)
continue;
if (rp->rcb_proto.sp_protocol
&& rp->rcb_proto.sp_protocol != PF_KEY_V2) {
continue;
}
/*
* If you are in promiscuous mode, and when you get broadcasted
* reply, you'll get two PF_KEY messages.
* (based on pf_key@inner.net message on 14 Oct 1998)
*/
kp = (struct keycb *)rp;
if (kp->kp_promisc) {
n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
if (n != NULL)
key_sendup0(rp, n, 1);
else
PFKEYSTAT_INC(in_nomem);
}
/* the exact target will be processed later */
if (so && sotorawcb(so) == rp)
continue;
if (target == KEY_SENDUP_ONE || (
target == KEY_SENDUP_REGISTERED && kp->kp_registered == 0))
continue;
/* KEY_SENDUP_ALL + KEY_SENDUP_REGISTERED */
n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
if (n == NULL) {
PFKEYSTAT_INC(in_nomem);
/* Try send to another socket */
continue;
}
if (key_sendup0(rp, n, 0) == 0)
PFKEYSTAT_INC(in_msgtarget[target]);
}
if (so) { /* KEY_SENDUP_ONE */
error = key_sendup0(sotorawcb(so), m, 0);
if (error == 0)
PFKEYSTAT_INC(in_msgtarget[KEY_SENDUP_ONE]);
} else {
error = 0;
m_freem(m);
}
mtx_unlock(&rawcb_mtx);
return (error);
}
/*
* key_abort()
* derived from net/rtsock.c:rts_abort()
*/
static void
key_abort(struct socket *so)
{
raw_usrreqs.pru_abort(so);
}
/*
* key_attach()
* derived from net/rtsock.c:rts_attach()
*/
static int
key_attach(struct socket *so, int proto, struct thread *td)
{
struct keycb *kp;
int error;
KASSERT(so->so_pcb == NULL, ("key_attach: so_pcb != NULL"));
if (td != NULL) {
error = priv_check(td, PRIV_NET_RAW);
if (error)
return error;
}
/* XXX */
kp = malloc(sizeof *kp, M_PCB, M_WAITOK | M_ZERO);
if (kp == NULL)
return ENOBUFS;
so->so_pcb = (caddr_t)kp;
error = raw_attach(so, proto);
kp = (struct keycb *)sotorawcb(so);
if (error) {
free(kp, M_PCB);
so->so_pcb = (caddr_t) 0;
return error;
}
kp->kp_promisc = kp->kp_registered = 0;
if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
V_key_cb.key_count++;
V_key_cb.any_count++;
soisconnected(so);
so->so_options |= SO_USELOOPBACK;
return 0;
}
/*
* key_bind()
* derived from net/rtsock.c:rts_bind()
*/
static int
key_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
{
return EINVAL;
}
/*
* key_close()
* derived from net/rtsock.c:rts_close().
*/
static void
key_close(struct socket *so)
{
raw_usrreqs.pru_close(so);
}
/*
* key_connect()
* derived from net/rtsock.c:rts_connect()
*/
static int
key_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
{
return EINVAL;
}
/*
* key_detach()
* derived from net/rtsock.c:rts_detach()
*/
static void
key_detach(struct socket *so)
{
struct keycb *kp = (struct keycb *)sotorawcb(so);
KASSERT(kp != NULL, ("key_detach: kp == NULL"));
if (kp->kp_raw.rcb_proto.sp_protocol
== PF_KEY) /* XXX: AF_KEY */
V_key_cb.key_count--;
V_key_cb.any_count--;
key_freereg(so);
raw_usrreqs.pru_detach(so);
}
/*
* key_disconnect()
* derived from net/rtsock.c:key_disconnect()
*/
static int
key_disconnect(struct socket *so)
{
return(raw_usrreqs.pru_disconnect(so));
}
/*
* key_peeraddr()
* derived from net/rtsock.c:rts_peeraddr()
*/
static int
key_peeraddr(struct socket *so, struct sockaddr **nam)
{
return(raw_usrreqs.pru_peeraddr(so, nam));
}
/*
* key_send()
* derived from net/rtsock.c:rts_send()
*/
static int
key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
struct mbuf *control, struct thread *td)
{
return(raw_usrreqs.pru_send(so, flags, m, nam, control, td));
}
/*
* key_shutdown()
* derived from net/rtsock.c:rts_shutdown()
*/
static int
key_shutdown(struct socket *so)
{
return(raw_usrreqs.pru_shutdown(so));
}
/*
* key_sockaddr()
* derived from net/rtsock.c:rts_sockaddr()
*/
static int
key_sockaddr(struct socket *so, struct sockaddr **nam)
{
return(raw_usrreqs.pru_sockaddr(so, nam));
}
struct pr_usrreqs key_usrreqs = {
.pru_abort = key_abort,
.pru_attach = key_attach,
.pru_bind = key_bind,
.pru_connect = key_connect,
.pru_detach = key_detach,
.pru_disconnect = key_disconnect,
.pru_peeraddr = key_peeraddr,
.pru_send = key_send,
.pru_shutdown = key_shutdown,
.pru_sockaddr = key_sockaddr,
.pru_close = key_close,
};
/* sysctl */
SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"Key Family");
/*
* Definitions of protocols supported in the KEY domain.
*/
extern struct domain keydomain;
struct protosw keysw[] = {
{
.pr_type = SOCK_RAW,
.pr_domain = &keydomain,
.pr_protocol = PF_KEY_V2,
.pr_flags = PR_ATOMIC|PR_ADDR,
.pr_output = key_output,
.pr_ctlinput = raw_ctlinput,
.pr_init = raw_init,
.pr_usrreqs = &key_usrreqs
}
};
static void
key_init0(void)
{
bzero((caddr_t)&V_key_cb, sizeof(V_key_cb));
key_init();
}
struct domain keydomain = {
.dom_family = PF_KEY,
.dom_name = "key",
.dom_init = key_init0,
#ifdef VIMAGE
.dom_destroy = key_destroy,
#endif
.dom_protosw = keysw,
.dom_protoswNPROTOSW = &keysw[nitems(keysw)]
};
VNET_DOMAIN_SET(key);