#include <sys/param.h>
#include <sys/systm.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <sys/protosw.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/malloc.h>
#include <net/if.h>
#include <net/route.h>
#include <net/if_types.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_var.h>
#include <netinet/ip_ecn.h>
#include <netinet/ip_encap.h>
#include <net/dlil.h>
#include <net/net_osdep.h>
#include <net/bpf.h>
#define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002)
#define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1]))
struct stf_softc {
struct ifnet sc_if;
#ifdef __APPLE__
u_long sc_protocol_family;
#endif
union {
struct route __sc_ro4;
struct route_in6 __sc_ro6;
} __sc_ro46;
#define sc_ro __sc_ro46.__sc_ro4
const struct encaptab *encap_cookie;
};
static struct stf_softc *stf;
#ifdef __APPLE__
void stfattach (void);
#endif
#ifndef __APPLE__
static MALLOC_DEFINE(M_STF, "stf", "6to4 Tunnel Interface");
#endif
static int ip_stf_ttl = 40;
static void in_stf_input(struct mbuf *, int);
extern struct domain inetdomain;
struct protosw in_stf_protosw =
{ SOCK_RAW, &inetdomain, IPPROTO_IPV6, PR_ATOMIC|PR_ADDR,
in_stf_input, 0, 0, rip_ctloutput,
0,
0,
&rip_usrreqs,
0, rip_unlock, 0
};
static int stf_encapcheck(const struct mbuf *, int, int, void *);
static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *);
int stf_pre_output(struct ifnet *, u_long, register struct mbuf **,
const struct sockaddr *, caddr_t, char *, char *);
static int stf_checkaddr4(struct stf_softc *, struct in_addr *,
struct ifnet *);
static int stf_checkaddr6(struct stf_softc *, struct in6_addr *,
struct ifnet *);
static void stf_rtrequest(int, struct rtentry *, struct sockaddr *);
int stf_ioctl(struct ifnet *, u_long, void *);
static
int stf_add_proto(
struct ifnet *ifp,
u_long protocol_family,
struct ddesc_head_str *desc_head)
{
struct stf_softc* stf = (struct stf_softc*)ifp;
if (stf->sc_protocol_family == 0)
stf->sc_protocol_family = protocol_family;
else {
printf("stf_add_proto: stf already has a proto\n");
return EBUSY;
}
return 0;
}
static
int stf_del_proto(
struct ifnet *ifp,
u_long protocol_family)
{
if (((struct stf_softc*)ifp)->sc_protocol_family == protocol_family)
((struct stf_softc*)ifp)->sc_protocol_family = 0;
else
return ENOENT;
return 0;
}
static int
stf_attach_inet6(struct ifnet *ifp, u_long protocol_family)
{
struct dlil_proto_reg_str reg;
int stat, i;
bzero(®, sizeof(reg));
TAILQ_INIT(®.demux_desc_head);
reg.interface_family = ifp->if_family;
reg.unit_number = ifp->if_unit;
reg.pre_output = stf_pre_output;
reg.protocol_family = PF_INET6;
stat = dlil_attach_protocol(®);
return stat;
}
static int
stf_demux(
struct ifnet *ifp,
struct mbuf *m,
char *frame_ptr,
u_long *protocol_family)
{
*protocol_family = PF_INET6;
return 0;
}
void stf_reg_if_mods()
{
int error;
if ( error = dlil_reg_proto_module(AF_INET6, APPLE_IF_FAM_STF, stf_attach_inet6, NULL) != 0)
kprintf("dlil_reg_proto_module failed for AF_INET6 error=%d\n", error);
}
void
stfattach(void)
{
struct ifnet *ifp;
struct stf_softc *sc;
int i, error;
int err;
const struct encaptab *p;
stf_reg_if_mods();
sc = _MALLOC(sizeof(struct stf_softc), M_DEVBUF, M_WAITOK);
if (sc == 0) {
printf("stf softc attach failed\n" );
return;
}
bzero(sc, sizeof(*sc));
sc->sc_if.if_name = "stf";
sc->sc_if.if_unit = 0;
p = encap_attach_func(AF_INET, IPPROTO_IPV6, stf_encapcheck,
&in_stf_protosw, sc);
if (p == NULL) {
printf("%s: attach failed\n", if_name(&sc->sc_if));
FREE(sc, M_DEVBUF);
return;
}
sc->encap_cookie = p;
sc->sc_if.if_mtu = IPV6_MMTU;
sc->sc_if.if_flags = 0;
sc->sc_if.if_ioctl = stf_ioctl;
sc->sc_if.if_output = NULL;
sc->sc_if.if_type = IFT_STF;
sc->sc_if.if_family= APPLE_IF_FAM_STF;
sc->sc_if.if_add_proto = stf_add_proto;
sc->sc_if.if_del_proto = stf_del_proto;
sc->sc_if.if_demux = stf_demux;
#if 0
sc->sc_if.if_flags |= IFF_LINK2;
#endif
sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
if (error = dlil_if_attach(&sc->sc_if))
printf("stfattach: can't dlil_if_attach error=%d\n");
else
bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int));
return ;
}
static int
stf_encapcheck(m, off, proto, arg)
const struct mbuf *m;
int off;
int proto;
void *arg;
{
struct ip ip;
struct in6_ifaddr *ia6;
struct stf_softc *sc;
struct in_addr a, b;
sc = (struct stf_softc *)arg;
if (sc == NULL)
return 0;
if ((sc->sc_if.if_flags & IFF_UP) == 0)
return 0;
if ((sc->sc_if.if_flags & IFF_LINK0) != 0)
return 0;
if (proto != IPPROTO_IPV6)
return 0;
m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip);
if (ip.ip_v != 4)
return 0;
ia6 = stf_getsrcifa6(&sc->sc_if);
if (ia6 == NULL)
return 0;
if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst,
sizeof(ip.ip_dst)) != 0)
return 0;
bzero(&a, sizeof(a));
a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr;
a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
b = ip.ip_src;
b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
if (a.s_addr != b.s_addr)
return 0;
return 32;
}
static struct in6_ifaddr *
stf_getsrcifa6(ifp)
struct ifnet *ifp;
{
struct ifaddr *ia;
struct in_ifaddr *ia4;
struct sockaddr_in6 *sin6;
struct in_addr in;
ifnet_lock_shared(ifp);
for (ia = ifp->if_addrlist.tqh_first;
ia;
ia = ia->ifa_list.tqe_next)
{
if (ia->ifa_addr == NULL)
continue;
if (ia->ifa_addr->sa_family != AF_INET6)
continue;
sin6 = (struct sockaddr_in6 *)ia->ifa_addr;
if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr))
continue;
bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in));
lck_mtx_lock(rt_mtx);
for (ia4 = TAILQ_FIRST(&in_ifaddrhead);
ia4;
ia4 = TAILQ_NEXT(ia4, ia_link))
{
if (ia4->ia_addr.sin_addr.s_addr == in.s_addr)
break;
}
lck_mtx_unlock(rt_mtx);
if (ia4 == NULL)
continue;
ifnet_lock_done(ifp);
return (struct in6_ifaddr *)ia;
}
ifnet_lock_done(ifp);
return NULL;
}
int
stf_pre_output(
struct ifnet *ifp,
u_long protocol_family,
register struct mbuf **m0,
const struct sockaddr *dst,
caddr_t rt,
char *frame_type,
char *address)
{
register struct mbuf *m = *m0;
struct stf_softc *sc;
struct sockaddr_in6 *dst6;
struct in_addr *in4;
struct sockaddr_in *dst4;
u_int8_t tos;
struct ip *ip;
struct ip6_hdr *ip6;
struct in6_ifaddr *ia6;
int error = 0 ;
sc = (struct stf_softc*)ifp;
dst6 = (struct sockaddr_in6 *)dst;
if ((ifp->if_flags & IFF_UP) == 0) {
printf("stf: IFF_DOWN\n");
return ENETDOWN;
}
ia6 = stf_getsrcifa6(ifp);
if (ia6 == NULL) {
return ENETDOWN;
}
if (m->m_len < sizeof(*ip6)) {
m = m_pullup(m, sizeof(*ip6));
if (!m) {
*m0 = NULL;
return ENOBUFS;
}
}
ip6 = mtod(m, struct ip6_hdr *);
tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst))
in4 = GET_V4(&ip6->ip6_dst);
else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr))
in4 = GET_V4(&dst6->sin6_addr);
else {
return ENETUNREACH;
}
if (ifp->if_bpf) {
struct mbuf m1;
u_int32_t af = AF_INET6;
m1.m_next = m;
m1.m_len = 4;
m1.m_data = (char *)⁡
bpf_mtap(ifp, &m1);
}
M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
if (m && m->m_len < sizeof(struct ip))
m = m_pullup(m, sizeof(struct ip));
if (m == NULL) {
*m0 = NULL;
return ENOBUFS;
}
ip = mtod(m, struct ip *);
bzero(ip, sizeof(*ip));
bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr),
&ip->ip_src, sizeof(ip->ip_src));
bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst));
ip->ip_p = IPPROTO_IPV6;
ip->ip_ttl = ip_stf_ttl;
ip->ip_len = m->m_pkthdr.len;
if (ifp->if_flags & IFF_LINK1)
ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos);
else
ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos);
dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst;
if (dst4->sin_family != AF_INET ||
bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) {
dst4->sin_family = AF_INET;
dst4->sin_len = sizeof(struct sockaddr_in);
bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr));
if (sc->sc_ro.ro_rt) {
rtfree(sc->sc_ro.ro_rt);
sc->sc_ro.ro_rt = NULL;
}
}
if (sc->sc_ro.ro_rt == NULL) {
rtalloc(&sc->sc_ro);
if (sc->sc_ro.ro_rt == NULL) {
return ENETUNREACH;
}
}
error = ip_output(m, NULL, &sc->sc_ro, 0, NULL);
if (error == 0)
return EJUSTRETURN;
*m0 = NULL;
return error;
}
static int
stf_checkaddr4(sc, in, inifp)
struct stf_softc *sc;
struct in_addr *in;
struct ifnet *inifp;
{
struct in_ifaddr *ia4;
if (IN_MULTICAST(ntohl(in->s_addr)))
return -1;
switch ((ntohl(in->s_addr) & 0xff000000) >> 24) {
case 0: case 127: case 255:
return -1;
}
lck_mtx_lock(rt_mtx);
for (ia4 = TAILQ_FIRST(&in_ifaddrhead);
ia4;
ia4 = TAILQ_NEXT(ia4, ia_link))
{
if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
continue;
if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) {
lck_mtx_unlock(rt_mtx);
return -1;
}
}
lck_mtx_unlock(rt_mtx);
if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) {
struct sockaddr_in sin;
struct rtentry *rt;
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_len = sizeof(struct sockaddr_in);
sin.sin_addr = *in;
rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL);
if (!rt || rt->rt_ifp != inifp) {
#if 1
log(LOG_WARNING, "%s: packet from 0x%x dropped "
"due to ingress filter\n", if_name(&sc->sc_if),
(u_int32_t)ntohl(sin.sin_addr.s_addr));
#endif
if (rt)
rtfree(rt);
return -1;
}
rtfree(rt);
}
return 0;
}
static int
stf_checkaddr6(sc, in6, inifp)
struct stf_softc *sc;
struct in6_addr *in6;
struct ifnet *inifp;
{
if (IN6_IS_ADDR_6TO4(in6))
return stf_checkaddr4(sc, GET_V4(in6), inifp);
if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6))
return -1;
return 0;
}
static void
in_stf_input(m, off)
struct mbuf *m;
int off;
{
struct stf_softc *sc;
struct ip *ip;
struct ip6_hdr *ip6;
u_int8_t otos, itos;
int proto;
struct ifnet *ifp;
ip = mtod(m, struct ip *);
proto = ip->ip_p;
if (proto != IPPROTO_IPV6) {
m_freem(m);
return;
}
ip = mtod(m, struct ip *);
sc = (struct stf_softc *)encap_getarg(m);
if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) {
m_freem(m);
return;
}
ifp = &sc->sc_if;
if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 ||
stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) {
m_freem(m);
return;
}
otos = ip->ip_tos;
m_adj(m, off);
if (m->m_len < sizeof(*ip6)) {
m = m_pullup(m, sizeof(*ip6));
if (!m)
return;
}
ip6 = mtod(m, struct ip6_hdr *);
if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 ||
stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) {
m_freem(m);
return;
}
itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
if ((ifp->if_flags & IFF_LINK1) != 0)
ip_ecn_egress(ECN_ALLOWED, &otos, &itos);
else
ip_ecn_egress(ECN_NOCARE, &otos, &itos);
ip6->ip6_flow &= ~htonl(0xff << 20);
ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
m->m_pkthdr.rcvif = ifp;
if (ifp->if_bpf) {
struct mbuf m0;
u_int32_t af = AF_INET6;
m0.m_next = m;
m0.m_len = 4;
m0.m_data = (char *)⁡
#ifdef HAVE_OLD_BPF
bpf_mtap(ifp, &m0);
#else
bpf_mtap(ifp->if_bpf, &m0);
#endif
}
proto_input(PF_INET6, m);
ifp->if_ipackets++;
ifp->if_ibytes += m->m_pkthdr.len;
return;
}
static void
stf_rtrequest(cmd, rt, sa)
int cmd;
struct rtentry *rt;
struct sockaddr *sa;
{
if (rt)
rt->rt_rmx.rmx_mtu = IPV6_MMTU;
}
int
stf_ioctl(ifp, cmd, data)
struct ifnet *ifp;
u_long cmd;
void *data;
{
struct ifaddr *ifa;
struct ifreq *ifr;
struct sockaddr_in6 *sin6;
int error;
error = 0;
switch (cmd) {
case SIOCSIFADDR:
ifa = (struct ifaddr *)data;
if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) {
error = EAFNOSUPPORT;
break;
}
sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) {
if ( !(ifnet_flags( ifp ) & IFF_UP) ) {
ifa->ifa_rtrequest = stf_rtrequest;
ifnet_set_flags(ifp, IFF_UP, IFF_UP);
}
} else
error = EINVAL;
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
ifr = (struct ifreq *)data;
if (ifr && ifr->ifr_addr.sa_family == AF_INET6)
;
else
error = EAFNOSUPPORT;
break;
default:
error = EINVAL;
break;
}
return error;
}