NetBSD/sys/net/if_gre.c

1257 lines
29 KiB
C

/* $NetBSD: if_gre.c,v 1.101 2007/08/20 04:49:41 skd Exp $ */
/*
* Copyright (c) 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Heiko W.Rupp <hwr@pilhuhn.de>
*
* IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Encapsulate L3 protocols into IP
* See RFC 1701 and 1702 for more details.
* If_gre is compatible with Cisco GRE tunnels, so you can
* have a NetBSD box as the other end of a tunnel interface of a Cisco
* router. See gre(4) for more details.
* Also supported: IP in IP encaps (proto 55) as of RFC 2004
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_gre.c,v 1.101 2007/08/20 04:49:41 skd Exp $");
#include "opt_gre.h"
#include "opt_inet.h"
#include "bpfilter.h"
#ifdef INET
#include <sys/param.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/ioctl.h>
#include <sys/queue.h>
#if __NetBSD__
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/kauth.h>
#endif
#include <sys/kernel.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/kthread.h>
#include <machine/cpu.h>
#include <net/ethertypes.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#else
#error "Huh? if_gre without inet?"
#endif
#ifdef NETATALK
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#include <netatalk/at_extern.h>
#endif
#if NBPFILTER > 0
#include <sys/time.h>
#include <net/bpf.h>
#endif
#include <net/if_gre.h>
#include <compat/sys/socket.h>
#include <compat/sys/sockio.h>
/*
* It is not easy to calculate the right value for a GRE MTU.
* We leave this task to the admin and use the same default that
* other vendors use.
*/
#define GREMTU 1476
#ifdef GRE_DEBUG
#define GRE_DPRINTF(__sc, __fmt, ...) \
do { \
if (((__sc)->sc_if.if_flags & IFF_DEBUG) != 0) \
printf(__fmt, __VA_ARGS__); \
} while (/*CONSTCOND*/0)
#else
#define GRE_DPRINTF(__sc, __fmt, ...) do { } while (/*CONSTCOND*/0)
#endif /* GRE_DEBUG */
struct gre_softc_head gre_softc_list;
int ip_gre_ttl = GRE_TTL;
static int gre_clone_create(struct if_clone *, int);
static int gre_clone_destroy(struct ifnet *);
static struct if_clone gre_cloner =
IF_CLONE_INITIALIZER("gre", gre_clone_create, gre_clone_destroy);
static int gre_output(struct ifnet *, struct mbuf *,
const struct sockaddr *, struct rtentry *);
static int gre_ioctl(struct ifnet *, u_long, void *);
static int gre_compute_route(struct gre_softc *sc);
static void gre_closef(struct file **, struct lwp *);
static int gre_getsockname(struct socket *, struct mbuf *, struct lwp *);
static int gre_getpeername(struct socket *, struct mbuf *, struct lwp *);
static int gre_getnames(struct socket *, struct lwp *, struct sockaddr_in *,
struct sockaddr_in *);
/* Calling thread must hold sc->sc_mtx. */
static void
gre_stop(struct gre_softc *sc)
{
sc->sc_running = 0;
cv_signal(&sc->sc_join_cv);
}
/* Calling thread must hold sc->sc_mtx. */
static void
gre_join(struct gre_softc *sc)
{
while (sc->sc_running != 0)
cv_wait(&sc->sc_join_cv, &sc->sc_mtx);
}
/* Calling thread must hold sc->sc_mtx. */
static void
gre_wakeup(struct gre_softc *sc)
{
GRE_DPRINTF(sc, "%s: enter\n", __func__);
sc->sc_haswork = 1;
cv_signal(&sc->sc_work_cv);
}
static int
gre_clone_create(struct if_clone *ifc, int unit)
{
struct gre_softc *sc;
sc = malloc(sizeof(struct gre_softc), M_DEVBUF, M_WAITOK);
memset(sc, 0, sizeof(struct gre_softc));
mutex_init(&sc->sc_mtx, MUTEX_DRIVER, IPL_NET);
cv_init(&sc->sc_work_cv, "gre work");
cv_init(&sc->sc_join_cv, "gre join");
cv_init(&sc->sc_soparm_cv, "gre soparm");
snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), "%s%d",
ifc->ifc_name, unit);
sc->sc_if.if_softc = sc;
sc->sc_if.if_type = IFT_TUNNEL;
sc->sc_if.if_addrlen = 0;
sc->sc_if.if_hdrlen = 24; /* IP + GRE */
sc->sc_if.if_dlt = DLT_NULL;
sc->sc_if.if_mtu = GREMTU;
sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
sc->sc_if.if_output = gre_output;
sc->sc_if.if_ioctl = gre_ioctl;
sc->g_dst.s_addr = sc->g_src.s_addr = INADDR_ANY;
sc->g_dstport = sc->g_srcport = 0;
sc->sc_proto = IPPROTO_GRE;
sc->sc_snd.ifq_maxlen = 256;
sc->sc_if.if_flags |= IFF_LINK0;
if_attach(&sc->sc_if);
if_alloc_sadl(&sc->sc_if);
#if NBPFILTER > 0
bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int32_t));
#endif
LIST_INSERT_HEAD(&gre_softc_list, sc, sc_list);
return 0;
}
static int
gre_clone_destroy(struct ifnet *ifp)
{
struct gre_softc *sc = ifp->if_softc;
LIST_REMOVE(sc, sc_list);
#if NBPFILTER > 0
bpfdetach(ifp);
#endif
if_detach(ifp);
mutex_enter(&sc->sc_mtx);
gre_wakeup(sc);
gre_join(sc);
mutex_exit(&sc->sc_mtx);
rtcache_free(&sc->route);
cv_destroy(&sc->sc_soparm_cv);
cv_destroy(&sc->sc_join_cv);
cv_destroy(&sc->sc_work_cv);
mutex_destroy(&sc->sc_mtx);
free(sc, M_DEVBUF);
return 0;
}
static void
gre_receive(struct socket *so, void *arg, int waitflag)
{
struct gre_softc *sc = (struct gre_softc *)arg;
GRE_DPRINTF(sc, "%s: enter\n", __func__);
gre_wakeup(sc);
}
static void
gre_upcall_add(struct socket *so, void *arg)
{
/* XXX What if the kernel already set an upcall? */
so->so_upcallarg = arg;
so->so_upcall = gre_receive;
so->so_rcv.sb_flags |= SB_UPCALL;
}
static void
gre_upcall_remove(struct socket *so)
{
/* XXX What if the kernel already set an upcall? */
so->so_rcv.sb_flags &= ~SB_UPCALL;
so->so_upcallarg = NULL;
so->so_upcall = NULL;
}
static void
gre_sodestroy(struct socket **sop)
{
gre_upcall_remove(*sop);
soshutdown(*sop, SHUT_RDWR);
soclose(*sop);
*sop = NULL;
}
static struct mbuf *
gre_getsockmbuf(struct socket *so)
{
struct mbuf *m;
m = m_get(M_WAIT, MT_SONAME);
if (m != NULL)
MCLAIM(m, so->so_mowner);
return m;
}
static int
gre_socreate1(struct gre_softc *sc, struct lwp *l, struct gre_soparm *sp,
struct socket **sop)
{
int rc;
struct mbuf *m;
struct sockaddr_in *sin;
struct socket *so;
GRE_DPRINTF(sc, "%s: enter\n", __func__);
rc = socreate(AF_INET, sop, SOCK_DGRAM, IPPROTO_UDP, l);
if (rc != 0) {
GRE_DPRINTF(sc, "%s: socreate failed\n", __func__);
return rc;
}
so = *sop;
gre_upcall_add(so, sc);
if ((m = gre_getsockmbuf(so)) == NULL) {
rc = ENOBUFS;
goto out;
}
sin = mtod(m, struct sockaddr_in *);
sin->sin_len = m->m_len = sizeof(struct sockaddr_in);
sin->sin_family = AF_INET;
sin->sin_addr = sc->g_src;
sin->sin_port = sc->g_srcport;
GRE_DPRINTF(sc, "%s: bind 0x%08" PRIx32 " port %d\n", __func__,
sin->sin_addr.s_addr, ntohs(sin->sin_port));
if ((rc = sobind(so, m, l)) != 0) {
GRE_DPRINTF(sc, "%s: sobind failed\n", __func__);
goto out;
}
if (sc->g_srcport == 0) {
if ((rc = gre_getsockname(so, m, l)) != 0) {
GRE_DPRINTF(sc, "%s: gre_getsockname failed\n",
__func__);
goto out;
}
sc->g_srcport = sin->sin_port;
}
sin->sin_addr = sc->g_dst;
sin->sin_port = sc->g_dstport;
if ((rc = soconnect(so, m, l)) != 0) {
GRE_DPRINTF(sc, "%s: soconnect failed\n", __func__);
goto out;
}
*mtod(m, int *) = ip_gre_ttl;
m->m_len = sizeof(int);
KASSERT(so->so_proto && so->so_proto->pr_ctloutput);
rc = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so, IPPROTO_IP, IP_TTL,
&m);
m = NULL;
if (rc != 0) {
printf("%s: setopt ttl failed\n", __func__);
rc = 0;
}
out:
m_freem(m);
if (rc != 0)
gre_sodestroy(sop);
else
*sp = sc->sc_soparm;
return rc;
}
static void
gre_thread1(struct gre_softc *sc, struct lwp *l)
{
int flags, rc;
const struct gre_h *gh;
struct ifnet *ifp = &sc->sc_if;
struct mbuf *m;
struct socket *so = NULL;
struct uio uio;
struct gre_soparm sp;
struct file *fp = NULL;
GRE_DPRINTF(sc, "%s: enter\n", __func__);
mutex_enter(&sc->sc_mtx);
sc->sc_haswork = 1;
memset(&sp, 0, sizeof(sp));
memset(&uio, 0, sizeof(uio));
ifp->if_flags |= IFF_RUNNING;
for (;;) {
while (sc->sc_haswork == 0) {
GRE_DPRINTF(sc, "%s: sleeping\n", __func__);
cv_wait(&sc->sc_work_cv, &sc->sc_mtx);
}
sc->sc_haswork = 0;
GRE_DPRINTF(sc, "%s: awake\n", __func__);
if ((ifp->if_flags & IFF_UP) != IFF_UP) {
GRE_DPRINTF(sc, "%s: not up & running; exiting\n",
__func__);
break;
}
if (sc->sc_proto != IPPROTO_UDP) {
GRE_DPRINTF(sc, "%s: not udp; exiting\n", __func__);
break;
}
/* XXX optimize */
if (so == NULL || sc->sc_fp != NULL ||
memcmp(&sp, &sc->sc_soparm, sizeof(sp)) != 0) {
GRE_DPRINTF(sc, "%s: parameters changed\n", __func__);
if (fp != NULL) {
gre_closef(&fp, curlwp);
so = NULL;
} else if (so != NULL)
gre_sodestroy(&so);
if (sc->sc_fp != NULL) {
fp = sc->sc_fp;
sc->sc_fp = NULL;
so = (struct socket *)fp->f_data;
gre_upcall_add(so, sc);
sp = sc->sc_soparm;
} else if (gre_socreate1(sc, l, &sp, &so) != 0)
goto out;
}
cv_signal(&sc->sc_soparm_cv);
for (;;) {
flags = MSG_DONTWAIT;
uio.uio_resid = 1000000;
rc = (*so->so_receive)(so, NULL, &uio, &m, NULL,
&flags);
/* TBD Back off if ECONNREFUSED (indicates
* ICMP Port Unreachable)?
*/
if (rc == EWOULDBLOCK) {
GRE_DPRINTF(sc, "%s: so_receive EWOULDBLOCK\n",
__func__);
break;
} else if (rc != 0 || m == NULL) {
GRE_DPRINTF(sc, "%s: rc %d m %p\n",
ifp->if_xname, rc, (void *)m);
continue;
} else
GRE_DPRINTF(sc, "%s: so_receive ok\n",
__func__);
if (m->m_len < sizeof(*gh) &&
(m = m_pullup(m, sizeof(*gh))) == NULL) {
GRE_DPRINTF(sc, "%s: m_pullup failed\n",
__func__);
continue;
}
gh = mtod(m, const struct gre_h *);
if (gre_input3(sc, m, 0, gh, 1) == 0) {
GRE_DPRINTF(sc, "%s: dropping unsupported\n",
__func__);
m_freem(m);
}
}
for (;;) {
IF_DEQUEUE(&sc->sc_snd, m);
if (m == NULL)
break;
GRE_DPRINTF(sc, "%s: dequeue\n", __func__);
if ((so->so_state & SS_ISCONNECTED) == 0) {
GRE_DPRINTF(sc, "%s: not connected\n",
__func__);
m_freem(m);
continue;
}
rc = (*so->so_send)(so, NULL, NULL, m, NULL, 0, l);
/* XXX handle ENOBUFS? */
if (rc != 0)
GRE_DPRINTF(sc, "%s: so_send failed\n",
__func__);
}
}
if (fp != NULL) {
GRE_DPRINTF(sc, "%s: removing upcall\n", __func__);
gre_upcall_remove(so);
} else if (so != NULL)
gre_sodestroy(&so);
out:
GRE_DPRINTF(sc, "%s: stopping\n", __func__);
if (fp != NULL)
gre_closef(&fp, curlwp);
if (sc->sc_proto == IPPROTO_UDP)
ifp->if_flags &= ~IFF_RUNNING;
while (!IF_IS_EMPTY(&sc->sc_snd)) {
IF_DEQUEUE(&sc->sc_snd, m);
m_freem(m);
}
gre_stop(sc);
/* must not touch sc after this! */
GRE_DPRINTF(sc, "%s: restore ipl\n", __func__);
mutex_exit(&sc->sc_mtx);
}
static void
gre_thread(void *arg)
{
struct gre_softc *sc = (struct gre_softc *)arg;
gre_thread1(sc, curlwp);
/* must not touch sc after this! */
kthread_exit(0);
}
/* Calling thread must hold sc->sc_mtx. */
int
gre_input3(struct gre_softc *sc, struct mbuf *m, int hlen,
const struct gre_h *gh, int mtx_held)
{
u_int16_t flags;
#if NBPFILTER > 0
u_int32_t af = AF_INET; /* af passed to BPF tap */
#endif
int isr;
struct ifqueue *ifq;
sc->sc_if.if_ipackets++;
sc->sc_if.if_ibytes += m->m_pkthdr.len;
hlen += sizeof(struct gre_h);
/* process GRE flags as packet can be of variable len */
flags = ntohs(gh->flags);
/* Checksum & Offset are present */
if ((flags & GRE_CP) | (flags & GRE_RP))
hlen += 4;
/* We don't support routing fields (variable length) */
if (flags & GRE_RP) {
sc->sc_if.if_ierrors++;
return 0;
}
if (flags & GRE_KP)
hlen += 4;
if (flags & GRE_SP)
hlen += 4;
switch (ntohs(gh->ptype)) { /* ethertypes */
case ETHERTYPE_IP: /* shouldn't need a schednetisr(), as */
ifq = &ipintrq; /* we are in ip_input */
isr = NETISR_IP;
break;
#ifdef NETATALK
case ETHERTYPE_ATALK:
ifq = &atintrq1;
isr = NETISR_ATALK;
#if NBPFILTER > 0
af = AF_APPLETALK;
#endif
break;
#endif
#ifdef INET6
case ETHERTYPE_IPV6:
GRE_DPRINTF(sc, "%s: IPv6 packet\n", __func__);
ifq = &ip6intrq;
isr = NETISR_IPV6;
#if NBPFILTER > 0
af = AF_INET6;
#endif
break;
#endif
default: /* others not yet supported */
GRE_DPRINTF(sc, "%s: unhandled ethertype 0x%04x\n", __func__,
ntohs(gh->ptype));
sc->sc_if.if_noproto++;
return 0;
}
if (hlen > m->m_pkthdr.len) {
m_freem(m);
sc->sc_if.if_ierrors++;
return EINVAL;
}
m_adj(m, hlen);
#if NBPFILTER > 0
if (sc->sc_if.if_bpf != NULL)
bpf_mtap_af(sc->sc_if.if_bpf, af, m);
#endif /*NBPFILTER > 0*/
m->m_pkthdr.rcvif = &sc->sc_if;
if (!mtx_held)
mutex_enter(&sc->sc_mtx);
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
m_freem(m);
} else {
IF_ENQUEUE(ifq, m);
}
/* we need schednetisr since the address family may change */
schednetisr(isr);
if (!mtx_held)
mutex_exit(&sc->sc_mtx);
return 1; /* packet is done, no further processing needed */
}
/*
* The output routine. Takes a packet and encapsulates it in the protocol
* given by sc->sc_proto. See also RFC 1701 and RFC 2004
*/
static int
gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
struct rtentry *rt)
{
int error = 0, hlen, msiz;
struct gre_softc *sc = ifp->if_softc;
struct greip *gi;
struct gre_h *gh;
struct ip *eip, *ip;
u_int8_t ip_tos = 0;
u_int16_t etype = 0;
struct mobile_h mob_h;
if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) !=
(IFF_UP | IFF_RUNNING) ||
sc->g_src.s_addr == INADDR_ANY || sc->g_dst.s_addr == INADDR_ANY) {
m_freem(m);
error = ENETDOWN;
goto end;
}
gi = NULL;
ip = NULL;
#if NBPFILTER >0
if (ifp->if_bpf)
bpf_mtap_af(ifp->if_bpf, dst->sa_family, m);
#endif
m->m_flags &= ~(M_BCAST|M_MCAST);
switch (sc->sc_proto) {
case IPPROTO_MOBILE:
if (dst->sa_family != AF_INET) {
IF_DROP(&ifp->if_snd);
m_freem(m);
error = EINVAL;
goto end;
}
if (M_UNWRITABLE(m, sizeof(*ip)) &&
(m = m_pullup(m, sizeof(*ip))) == NULL) {
error = ENOBUFS;
goto end;
}
ip = mtod(m, struct ip *);
memset(&mob_h, 0, MOB_H_SIZ_L);
mob_h.proto = (ip->ip_p) << 8;
mob_h.odst = ip->ip_dst.s_addr;
ip->ip_dst.s_addr = sc->g_dst.s_addr;
/*
* If the packet comes from our host, we only change
* the destination address in the IP header.
* Else we also need to save and change the source
*/
if (in_hosteq(ip->ip_src, sc->g_src)) {
msiz = MOB_H_SIZ_S;
} else {
mob_h.proto |= MOB_H_SBIT;
mob_h.osrc = ip->ip_src.s_addr;
ip->ip_src.s_addr = sc->g_src.s_addr;
msiz = MOB_H_SIZ_L;
}
HTONS(mob_h.proto);
mob_h.hcrc = gre_in_cksum((u_int16_t *)&mob_h, msiz);
M_PREPEND(m, msiz, M_DONTWAIT);
if (m == NULL) {
error = ENOBUFS;
goto end;
}
/* XXX Assuming that ip does not dangle after
* M_PREPEND. In practice, that's true, but
* that's not in M_PREPEND's contract.
*/
memmove(mtod(m, void *), ip, sizeof(*ip));
ip = mtod(m, struct ip *);
memcpy(ip + 1, &mob_h, (size_t)msiz);
ip->ip_len = htons(ntohs(ip->ip_len) + msiz);
break;
case IPPROTO_UDP:
case IPPROTO_GRE:
GRE_DPRINTF(sc, "%s: dst->sa_family=%d\n", __func__,
dst->sa_family);
switch (dst->sa_family) {
case AF_INET:
ip = mtod(m, struct ip *);
ip_tos = ip->ip_tos;
etype = ETHERTYPE_IP;
break;
#ifdef NETATALK
case AF_APPLETALK:
etype = ETHERTYPE_ATALK;
break;
#endif
#ifdef INET6
case AF_INET6:
etype = ETHERTYPE_IPV6;
break;
#endif
default:
IF_DROP(&ifp->if_snd);
m_freem(m);
error = EAFNOSUPPORT;
goto end;
}
break;
default:
IF_DROP(&ifp->if_snd);
m_freem(m);
error = EINVAL;
goto end;
}
switch (sc->sc_proto) {
case IPPROTO_GRE:
hlen = sizeof(struct greip);
break;
case IPPROTO_UDP:
hlen = sizeof(struct gre_h);
break;
default:
hlen = 0;
break;
}
M_PREPEND(m, hlen, M_DONTWAIT);
if (m == NULL) {
IF_DROP(&ifp->if_snd);
error = ENOBUFS;
goto end;
}
switch (sc->sc_proto) {
case IPPROTO_UDP:
gh = mtod(m, struct gre_h *);
memset(gh, 0, sizeof(*gh));
gh->ptype = htons(etype);
/* XXX Need to handle IP ToS. Look at how I handle IP TTL. */
break;
case IPPROTO_GRE:
gi = mtod(m, struct greip *);
gh = &gi->gi_g;
eip = &gi->gi_i;
/* we don't have any GRE flags for now */
memset(gh, 0, sizeof(*gh));
gh->ptype = htons(etype);
eip->ip_src = sc->g_src;
eip->ip_dst = sc->g_dst;
eip->ip_hl = (sizeof(struct ip)) >> 2;
eip->ip_ttl = ip_gre_ttl;
eip->ip_tos = ip_tos;
eip->ip_len = htons(m->m_pkthdr.len);
eip->ip_p = sc->sc_proto;
break;
case IPPROTO_MOBILE:
eip = mtod(m, struct ip *);
eip->ip_p = sc->sc_proto;
break;
default:
error = EPROTONOSUPPORT;
m_freem(m);
goto end;
}
ifp->if_opackets++;
ifp->if_obytes += m->m_pkthdr.len;
/* send it off */
if (sc->sc_proto == IPPROTO_UDP) {
if (IF_QFULL(&sc->sc_snd)) {
IF_DROP(&sc->sc_snd);
error = ENOBUFS;
m_freem(m);
} else {
IF_ENQUEUE(&sc->sc_snd, m);
gre_wakeup(sc);
error = 0;
}
goto end;
}
if (sc->route.ro_rt == NULL)
rtcache_init(&sc->route);
else
rtcache_check(&sc->route);
if (sc->route.ro_rt == NULL) {
m_freem(m);
goto end;
}
if (sc->route.ro_rt->rt_ifp->if_softc == sc) {
rtcache_clear(&sc->route);
m_freem(m);
} else
error = ip_output(m, NULL, &sc->route, 0, NULL, NULL);
end:
if (error)
ifp->if_oerrors++;
return error;
}
/* Calling thread must hold sc->sc_mtx. */
static int
gre_kick(struct gre_softc *sc)
{
int rc;
struct ifnet *ifp = &sc->sc_if;
if (sc->sc_proto == IPPROTO_UDP && (ifp->if_flags & IFF_UP) == IFF_UP &&
!sc->sc_running) {
sc->sc_running = 1;
rc = kthread_create(PRI_NONE, 0, NULL, gre_thread, sc,
NULL, ifp->if_xname);
if (rc != 0)
gre_stop(sc);
return rc;
} else {
gre_wakeup(sc);
return 0;
}
}
/* Calling thread must hold sc->sc_mtx. */
static int
gre_getname(struct socket *so, int req, struct mbuf *nam, struct lwp *l)
{
return (*so->so_proto->pr_usrreq)(so, req, NULL, nam, NULL, l);
}
/* Calling thread must hold sc->sc_mtx. */
static int
gre_getsockname(struct socket *so, struct mbuf *nam, struct lwp *l)
{
return gre_getname(so, PRU_SOCKADDR, nam, l);
}
/* Calling thread must hold sc->sc_mtx. */
static int
gre_getpeername(struct socket *so, struct mbuf *nam, struct lwp *l)
{
return gre_getname(so, PRU_PEERADDR, nam, l);
}
/* Calling thread must hold sc->sc_mtx. */
static int
gre_getnames(struct socket *so, struct lwp *l, struct sockaddr_in *src,
struct sockaddr_in *dst)
{
struct mbuf *m;
struct sockaddr_in *sin;
int rc;
if ((m = gre_getsockmbuf(so)) == NULL)
return ENOBUFS;
sin = mtod(m, struct sockaddr_in *);
if ((rc = gre_getsockname(so, m, l)) != 0)
goto out;
if (sin->sin_family != AF_INET) {
rc = EAFNOSUPPORT;
goto out;
}
*src = *sin;
if ((rc = gre_getpeername(so, m, l)) != 0)
goto out;
if (sin->sin_family != AF_INET) {
rc = EAFNOSUPPORT;
goto out;
}
*dst = *sin;
out:
m_freem(m);
return rc;
}
static void
gre_closef(struct file **fpp, struct lwp *l)
{
struct file *fp = *fpp;
simple_lock(&fp->f_slock);
FILE_USE(fp);
closef(fp, l);
*fpp = NULL;
}
static int
gre_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
u_char oproto;
struct file *fp;
struct socket *so;
struct sockaddr_in dst, src;
struct proc *p = curproc; /* XXX */
struct lwp *l = curlwp; /* XXX */
struct ifreq *ifr;
struct if_laddrreq *lifr = (struct if_laddrreq *)data;
struct gre_softc *sc = ifp->if_softc;
struct sockaddr_in si;
struct sockaddr *sa = NULL;
int error = 0;
#ifdef COMPAT_OIFREQ
u_long ocmd = cmd;
struct oifreq *oifr = NULL;
struct ifreq ifrb;
cmd = compat_cvtcmd(cmd);
if (cmd != ocmd) {
oifr = data;
data = ifr = &ifrb;
ifreqo2n(oifr, ifr);
} else
#endif
ifr = data;
switch (cmd) {
case SIOCSIFFLAGS:
case SIOCSIFMTU:
case GRESPROTO:
case GRESADDRD:
case GRESADDRS:
case GRESSOCK:
case GREDSOCK:
case SIOCSLIFPHYADDR:
case SIOCDIFPHYADDR:
if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE,
KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
NULL) != 0)
return EPERM;
break;
default:
break;
}
mutex_enter(&sc->sc_mtx);
switch (cmd) {
case SIOCSIFADDR:
ifp->if_flags |= IFF_UP;
if ((error = gre_kick(sc)) != 0)
ifp->if_flags &= ~IFF_UP;
break;
case SIOCSIFDSTADDR:
break;
case SIOCSIFFLAGS:
oproto = sc->sc_proto;
switch (ifr->ifr_flags & (IFF_LINK0|IFF_LINK2)) {
case IFF_LINK0|IFF_LINK2:
sc->sc_proto = IPPROTO_UDP;
if (oproto != IPPROTO_UDP)
ifp->if_flags &= ~IFF_RUNNING;
error = gre_kick(sc);
break;
case IFF_LINK0:
sc->sc_proto = IPPROTO_GRE;
gre_wakeup(sc);
goto recompute;
case 0:
sc->sc_proto = IPPROTO_MOBILE;
gre_wakeup(sc);
goto recompute;
}
break;
case SIOCSIFMTU:
if (ifr->ifr_mtu < 576) {
error = EINVAL;
break;
}
ifp->if_mtu = ifr->ifr_mtu;
break;
case SIOCGIFMTU:
ifr->ifr_mtu = sc->sc_if.if_mtu;
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
if (ifr == 0) {
error = EAFNOSUPPORT;
break;
}
switch (ifr->ifr_addr.sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef INET6
case AF_INET6:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
case GRESPROTO:
oproto = sc->sc_proto;
sc->sc_proto = ifr->ifr_flags;
switch (sc->sc_proto) {
case IPPROTO_UDP:
ifp->if_flags |= IFF_LINK0|IFF_LINK2;
if (oproto != IPPROTO_UDP)
ifp->if_flags &= ~IFF_RUNNING;
error = gre_kick(sc);
break;
case IPPROTO_GRE:
ifp->if_flags |= IFF_LINK0;
ifp->if_flags &= ~IFF_LINK2;
goto recompute;
case IPPROTO_MOBILE:
ifp->if_flags &= ~(IFF_LINK0|IFF_LINK2);
goto recompute;
default:
error = EPROTONOSUPPORT;
break;
}
break;
case GREGPROTO:
ifr->ifr_flags = sc->sc_proto;
break;
case GRESADDRS:
case GRESADDRD:
/*
* set tunnel endpoints, compute a less specific route
* to the remote end and mark if as up
*/
sa = &ifr->ifr_addr;
if (cmd == GRESADDRS) {
sc->g_src = (satosin(sa))->sin_addr;
sc->g_srcport = satosin(sa)->sin_port;
}
if (cmd == GRESADDRD) {
if (sc->sc_proto == IPPROTO_UDP &&
satosin(sa)->sin_port == 0) {
error = EINVAL;
break;
}
sc->g_dst = (satosin(sa))->sin_addr;
sc->g_dstport = satosin(sa)->sin_port;
}
recompute:
if (sc->sc_proto == IPPROTO_UDP ||
(sc->g_src.s_addr != INADDR_ANY &&
sc->g_dst.s_addr != INADDR_ANY)) {
rtcache_free(&sc->route);
if (sc->sc_proto == IPPROTO_UDP)
error = gre_kick(sc);
else if (gre_compute_route(sc) == 0)
ifp->if_flags |= IFF_RUNNING;
else
ifp->if_flags &= ~IFF_RUNNING;
}
break;
case GREGADDRS:
memset(&si, 0, sizeof(si));
si.sin_family = AF_INET;
si.sin_len = sizeof(struct sockaddr_in);
si.sin_addr.s_addr = sc->g_src.s_addr;
sa = sintosa(&si);
ifr->ifr_addr = *sa;
break;
case GREGADDRD:
memset(&si, 0, sizeof(si));
si.sin_family = AF_INET;
si.sin_len = sizeof(struct sockaddr_in);
si.sin_addr.s_addr = sc->g_dst.s_addr;
sa = sintosa(&si);
ifr->ifr_addr = *sa;
break;
case GREDSOCK:
if (sc->sc_proto != IPPROTO_UDP) {
error = EINVAL;
break;
}
ifp->if_flags &= ~IFF_UP;
gre_wakeup(sc);
break;
case GRESSOCK:
if (sc->sc_proto != IPPROTO_UDP) {
error = EINVAL;
break;
}
/* getsock() will FILE_USE() and unlock the descriptor for us */
if ((error = getsock(p->p_fd, (int)ifr->ifr_value, &fp)) != 0)
break;
so = (struct socket *)fp->f_data;
if (so->so_type != SOCK_DGRAM) {
FILE_UNUSE(fp, NULL);
error = EINVAL;
break;
}
/* check address */
if ((error = gre_getnames(so, curlwp, &src, &dst)) != 0) {
FILE_UNUSE(fp, NULL);
break;
}
/* Increase reference count. Now that our reference
* to the file descriptor is counted, this thread
* can release our "use" of the descriptor, but it
* will not be destroyed by some other thread's
* action. This thread needs to release its use,
* too, because one and only one thread can have
* use of the descriptor at once. The kernel thread
* will pick up the use if it needs it.
*/
fp->f_count++;
FILE_UNUSE(fp, NULL);
while (sc->sc_fp != NULL && error == 0) {
error = cv_timedwait_sig(&sc->sc_soparm_cv, &sc->sc_mtx,
MAX(1, hz / 2));
}
if (error == 0) {
sc->sc_fp = fp;
ifp->if_flags |= IFF_UP;
}
if (error != 0 || (error = gre_kick(sc)) != 0) {
gre_closef(&fp, l);
break;
}
/* fp does not any longer belong to this thread. */
sc->g_src = src.sin_addr;
sc->g_srcport = src.sin_port;
sc->g_dst = dst.sin_addr;
sc->g_dstport = dst.sin_port;
break;
case SIOCSLIFPHYADDR:
if (lifr->addr.ss_family != AF_INET ||
lifr->dstaddr.ss_family != AF_INET) {
error = EAFNOSUPPORT;
break;
}
if (lifr->addr.ss_len != sizeof(si) ||
lifr->dstaddr.ss_len != sizeof(si)) {
error = EINVAL;
break;
}
sc->g_src = satosin(&lifr->addr)->sin_addr;
sc->g_dst = satosin(&lifr->dstaddr)->sin_addr;
sc->g_srcport = satosin(&lifr->addr)->sin_port;
sc->g_dstport = satosin(&lifr->dstaddr)->sin_port;
goto recompute;
case SIOCDIFPHYADDR:
sc->g_src.s_addr = INADDR_ANY;
sc->g_dst.s_addr = INADDR_ANY;
sc->g_srcport = 0;
sc->g_dstport = 0;
goto recompute;
case SIOCGLIFPHYADDR:
if (sc->g_src.s_addr == INADDR_ANY ||
sc->g_dst.s_addr == INADDR_ANY) {
error = EADDRNOTAVAIL;
break;
}
memset(&si, 0, sizeof(si));
si.sin_family = AF_INET;
si.sin_len = sizeof(struct sockaddr_in);
si.sin_addr = sc->g_src;
if (sc->sc_proto == IPPROTO_UDP)
si.sin_port = sc->g_srcport;
memcpy(&lifr->addr, &si, sizeof(si));
si.sin_addr = sc->g_dst;
if (sc->sc_proto == IPPROTO_UDP)
si.sin_port = sc->g_dstport;
memcpy(&lifr->dstaddr, &si, sizeof(si));
break;
default:
error = EINVAL;
break;
}
#ifdef COMPAT_OIFREQ
if (cmd != ocmd)
ifreqn2o(oifr, ifr);
#endif
mutex_exit(&sc->sc_mtx);
return error;
}
/*
* Compute a route to our destination.
*/
static int
gre_compute_route(struct gre_softc *sc)
{
struct route *ro;
union {
struct sockaddr dst;
struct sockaddr_in dst4;
} u;
ro = &sc->route;
memset(ro, 0, sizeof(*ro));
sockaddr_in_init(&u.dst4, &sc->g_dst, 0);
rtcache_setdst(ro, &u.dst);
rtcache_init(ro);
if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp->if_softc == sc) {
GRE_DPRINTF(sc, "%s: route to %s %s\n", sc->sc_if.if_xname,
inet_ntoa(u.dst4.sin_addr),
(ro->ro_rt == NULL)
? "does not exist"
: "loops back to ourself");
rtcache_free(ro);
return EADDRNOTAVAIL;
}
return 0;
}
/*
* do a checksum of a buffer - much like in_cksum, which operates on
* mbufs.
*/
u_int16_t
gre_in_cksum(u_int16_t *p, u_int len)
{
u_int32_t sum = 0;
int nwords = len >> 1;
while (nwords-- != 0)
sum += *p++;
if (len & 1) {
union {
u_short w;
u_char c[2];
} u;
u.c[0] = *(u_char *)p;
u.c[1] = 0;
sum += u.w;
}
/* end-around-carry */
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16);
return ~sum;
}
#endif
void greattach(int);
/* ARGSUSED */
void
greattach(int count)
{
#ifdef INET
LIST_INIT(&gre_softc_list);
if_clone_attach(&gre_cloner);
#endif
}