diff options
Diffstat (limited to 'sys/net/if_gif.c')
| -rw-r--r-- | sys/net/if_gif.c | 722 |
1 files changed, 722 insertions, 0 deletions
diff --git a/sys/net/if_gif.c b/sys/net/if_gif.c new file mode 100644 index 000000000000..272ab214a788 --- /dev/null +++ b/sys/net/if_gif.c @@ -0,0 +1,722 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. + * Copyright (c) 2018 Andrey V. Elsukov <ae@FreeBSD.org> + * 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. + * + * $KAME: if_gif.c,v 1.87 2001/10/19 08:50:27 itojun Exp $ + */ + +#include <sys/cdefs.h> +#include "opt_inet.h" +#include "opt_inet6.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/malloc.h> +#include <sys/mbuf.h> +#include <sys/module.h> +#include <sys/rmlock.h> +#include <sys/socket.h> +#include <sys/sockio.h> +#include <sys/sx.h> +#include <sys/errno.h> +#include <sys/time.h> +#include <sys/sysctl.h> +#include <sys/syslog.h> +#include <sys/priv.h> +#include <sys/proc.h> +#include <sys/conf.h> +#include <machine/cpu.h> + +#include <net/if.h> +#include <net/if_var.h> +#include <net/if_private.h> +#include <net/if_clone.h> +#include <net/if_types.h> +#include <net/netisr.h> +#include <net/route.h> +#include <net/bpf.h> +#include <net/vnet.h> + +#include <netinet/in.h> +#include <netinet/in_systm.h> +#include <netinet/ip.h> +#include <netinet/ip_ecn.h> +#ifdef INET +#include <netinet/in_var.h> +#include <netinet/ip_var.h> +#endif /* INET */ + +#ifdef INET6 +#ifndef INET +#include <netinet/in.h> +#endif +#include <netinet6/in6_var.h> +#include <netinet/ip6.h> +#include <netinet6/ip6_ecn.h> +#include <netinet6/ip6_var.h> +#endif /* INET6 */ + +#include <netinet/ip_encap.h> +#include <net/ethernet.h> +#include <net/if_bridgevar.h> +#include <net/if_gif.h> + +#include <security/mac/mac_framework.h> + +static const char gifname[] = "gif"; + +MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface"); +static struct sx gif_ioctl_sx; +SX_SYSINIT(gif_ioctl_sx, &gif_ioctl_sx, "gif_ioctl"); + +void (*ng_gif_input_p)(struct ifnet *ifp, struct mbuf **mp, int af); +void (*ng_gif_input_orphan_p)(struct ifnet *ifp, struct mbuf *m, int af); +void (*ng_gif_attach_p)(struct ifnet *ifp); +void (*ng_gif_detach_p)(struct ifnet *ifp); + +#ifdef VIMAGE +static void gif_reassign(struct ifnet *, struct vnet *, char *); +#endif +static void gif_delete_tunnel(struct gif_softc *); +static int gif_ioctl(struct ifnet *, u_long, caddr_t); +static int gif_transmit(struct ifnet *, struct mbuf *); +static void gif_qflush(struct ifnet *); +static int gif_clone_create(struct if_clone *, int, caddr_t); +static void gif_clone_destroy(struct ifnet *); +VNET_DEFINE_STATIC(struct if_clone *, gif_cloner); +#define V_gif_cloner VNET(gif_cloner) + +SYSCTL_DECL(_net_link); +static SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, + "Generic Tunnel Interface"); +#ifndef MAX_GIF_NEST +/* + * This macro controls the default upper limitation on nesting of gif tunnels. + * Since, setting a large value to this macro with a careless configuration + * may introduce system crash, we don't allow any nestings by default. + * If you need to configure nested gif tunnels, you can define this macro + * in your kernel configuration file. However, if you do so, please be + * careful to configure the tunnels so that it won't make a loop. + */ +#define MAX_GIF_NEST 1 +#endif +VNET_DEFINE_STATIC(int, max_gif_nesting) = MAX_GIF_NEST; +#define V_max_gif_nesting VNET(max_gif_nesting) +SYSCTL_INT(_net_link_gif, OID_AUTO, max_nesting, CTLFLAG_VNET | CTLFLAG_RW, + &VNET_NAME(max_gif_nesting), 0, "Max nested tunnels"); + +static int +gif_clone_create(struct if_clone *ifc, int unit, caddr_t params) +{ + struct gif_softc *sc; + + sc = malloc(sizeof(struct gif_softc), M_GIF, M_WAITOK | M_ZERO); + sc->gif_fibnum = curthread->td_proc->p_fibnum; + GIF2IFP(sc) = if_alloc(IFT_GIF); + GIF2IFP(sc)->if_softc = sc; + if_initname(GIF2IFP(sc), gifname, unit); + + GIF2IFP(sc)->if_addrlen = 0; + GIF2IFP(sc)->if_mtu = GIF_MTU; + GIF2IFP(sc)->if_flags = IFF_POINTOPOINT | IFF_MULTICAST; + GIF2IFP(sc)->if_ioctl = gif_ioctl; + GIF2IFP(sc)->if_transmit = gif_transmit; + GIF2IFP(sc)->if_qflush = gif_qflush; + GIF2IFP(sc)->if_output = gif_output; +#ifdef VIMAGE + GIF2IFP(sc)->if_reassign = gif_reassign; +#endif + GIF2IFP(sc)->if_capabilities |= IFCAP_LINKSTATE; + GIF2IFP(sc)->if_capenable |= IFCAP_LINKSTATE; + if_attach(GIF2IFP(sc)); + bpfattach(GIF2IFP(sc), DLT_NULL, sizeof(u_int32_t)); + if (ng_gif_attach_p != NULL) + (*ng_gif_attach_p)(GIF2IFP(sc)); + + return (0); +} + +#ifdef VIMAGE +static void +gif_reassign(struct ifnet *ifp, struct vnet *new_vnet __unused, + char *unused __unused) +{ + struct gif_softc *sc; + + sx_xlock(&gif_ioctl_sx); + sc = ifp->if_softc; + if (sc != NULL) + gif_delete_tunnel(sc); + sx_xunlock(&gif_ioctl_sx); +} +#endif /* VIMAGE */ + +static void +gif_clone_destroy(struct ifnet *ifp) +{ + struct gif_softc *sc; + + sx_xlock(&gif_ioctl_sx); + sc = ifp->if_softc; + gif_delete_tunnel(sc); + if (ng_gif_detach_p != NULL) + (*ng_gif_detach_p)(ifp); + bpfdetach(ifp); + if_detach(ifp); + ifp->if_softc = NULL; + sx_xunlock(&gif_ioctl_sx); + + GIF_WAIT(); + if_free(ifp); + free(sc, M_GIF); +} + +static void +vnet_gif_init(const void *unused __unused) +{ + + V_gif_cloner = if_clone_simple(gifname, gif_clone_create, + gif_clone_destroy, 0); +#ifdef INET + in_gif_init(); +#endif +#ifdef INET6 + in6_gif_init(); +#endif +} +VNET_SYSINIT(vnet_gif_init, SI_SUB_PSEUDO, SI_ORDER_ANY, + vnet_gif_init, NULL); + +static void +vnet_gif_uninit(const void *unused __unused) +{ + + if_clone_detach(V_gif_cloner); +#ifdef INET + in_gif_uninit(); +#endif +#ifdef INET6 + in6_gif_uninit(); +#endif +} +VNET_SYSUNINIT(vnet_gif_uninit, SI_SUB_PSEUDO, SI_ORDER_ANY, + vnet_gif_uninit, NULL); + +static int +gifmodevent(module_t mod, int type, void *data) +{ + + switch (type) { + case MOD_LOAD: + case MOD_UNLOAD: + break; + default: + return (EOPNOTSUPP); + } + return (0); +} + +static moduledata_t gif_mod = { + "if_gif", + gifmodevent, + 0 +}; + +DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); +MODULE_VERSION(if_gif, 1); + +struct gif_list * +gif_hashinit(void) +{ + struct gif_list *hash; + int i; + + hash = malloc(sizeof(struct gif_list) * GIF_HASH_SIZE, + M_GIF, M_WAITOK); + for (i = 0; i < GIF_HASH_SIZE; i++) + CK_LIST_INIT(&hash[i]); + + return (hash); +} + +void +gif_hashdestroy(struct gif_list *hash) +{ + + free(hash, M_GIF); +} + +#define MTAG_GIF 1080679712 +static int +gif_transmit(struct ifnet *ifp, struct mbuf *m) +{ + struct gif_softc *sc; + struct etherip_header *eth; +#ifdef INET + struct ip *ip; +#endif +#ifdef INET6 + struct ip6_hdr *ip6; + uint32_t t; +#endif + uint32_t af; + uint8_t proto, ecn; + int error; + + NET_EPOCH_ASSERT(); +#ifdef MAC + error = mac_ifnet_check_transmit(ifp, m); + if (error) { + m_freem(m); + goto err; + } +#endif + error = ENETDOWN; + sc = ifp->if_softc; + if ((ifp->if_flags & IFF_MONITOR) != 0 || + (ifp->if_flags & IFF_UP) == 0 || + (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || + sc->gif_family == 0 || + (error = if_tunnel_check_nesting(ifp, m, MTAG_GIF, + V_max_gif_nesting)) != 0) { + m_freem(m); + goto err; + } + /* Now pull back the af that we stashed in the csum_data. */ + af = m->m_pkthdr.csum_data; + m->m_flags &= ~(M_BCAST|M_MCAST); + M_SETFIB(m, sc->gif_fibnum); + BPF_MTAP2(ifp, &af, sizeof(af), m); + if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); + if_inc_counter(ifp, IFCOUNTER_OBYTES, m->m_pkthdr.len); + /* inner AF-specific encapsulation */ + ecn = 0; + switch (af) { +#ifdef INET + case AF_INET: + proto = IPPROTO_IPV4; + if (m->m_len < sizeof(struct ip)) + m = m_pullup(m, sizeof(struct ip)); + if (m == NULL) { + error = ENOBUFS; + goto err; + } + ip = mtod(m, struct ip *); + ip_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED: + ECN_NOCARE, &ecn, &ip->ip_tos); + break; +#endif +#ifdef INET6 + case AF_INET6: + proto = IPPROTO_IPV6; + if (m->m_len < sizeof(struct ip6_hdr)) + m = m_pullup(m, sizeof(struct ip6_hdr)); + if (m == NULL) { + error = ENOBUFS; + goto err; + } + t = 0; + ip6 = mtod(m, struct ip6_hdr *); + ip6_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED: + ECN_NOCARE, &t, &ip6->ip6_flow); + ecn = (ntohl(t) >> 20) & 0xff; + break; +#endif + case AF_LINK: + KASSERT(ifp->if_bridge != NULL, + ("%s: bridge not attached", __func__)); + proto = IPPROTO_ETHERIP; + M_PREPEND(m, sizeof(struct etherip_header), M_NOWAIT); + if (m == NULL) { + error = ENOBUFS; + goto err; + } + eth = mtod(m, struct etherip_header *); + eth->eip_resvh = 0; + eth->eip_ver = ETHERIP_VERSION; + eth->eip_resvl = 0; + break; + default: + error = EAFNOSUPPORT; + m_freem(m); + goto err; + } + /* XXX should we check if our outer source is legal? */ + /* dispatch to output logic based on outer AF */ + switch (sc->gif_family) { +#ifdef INET + case AF_INET: + error = in_gif_output(ifp, m, proto, ecn); + break; +#endif +#ifdef INET6 + case AF_INET6: + error = in6_gif_output(ifp, m, proto, ecn); + break; +#endif + default: + m_freem(m); + } +err: + if (error) + if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); + return (error); +} + +static void +gif_qflush(struct ifnet *ifp __unused) +{ + +} + +int +gif_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, + struct route *ro) +{ + uint32_t af; + + /* BPF writes need to be handled specially. */ + if (dst->sa_family == AF_UNSPEC || dst->sa_family == pseudo_AF_HDRCMPLT) + memcpy(&af, dst->sa_data, sizeof(af)); + else + af = RO_GET_FAMILY(ro, dst); + /* + * Now save the af in the inbound pkt csum data, this is a cheat since + * we are using the inbound csum_data field to carry the af over to + * the gif_transmit() routine, avoiding using yet another mtag. + */ + m->m_pkthdr.csum_data = af; + return (ifp->if_transmit(ifp, m)); +} + +void +gif_input(struct mbuf *m, struct ifnet *ifp, int proto, uint8_t ecn) +{ + struct etherip_header *eip; +#ifdef INET + struct ip *ip; +#endif +#ifdef INET6 + struct ip6_hdr *ip6; + uint32_t t; +#endif + struct ether_header *eh; + struct ifnet *oldifp; + int isr, n, af; + + NET_EPOCH_ASSERT(); + + if (ifp == NULL) { + /* just in case */ + m_freem(m); + return; + } + m->m_pkthdr.rcvif = ifp; + m_clrprotoflags(m); + switch (proto) { +#ifdef INET + case IPPROTO_IPV4: + af = AF_INET; + if (m->m_len < sizeof(struct ip)) + m = m_pullup(m, sizeof(struct ip)); + if (m == NULL) + goto drop; + ip = mtod(m, struct ip *); + if (ip_ecn_egress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED: + ECN_NOCARE, &ecn, &ip->ip_tos) == 0) { + m_freem(m); + goto drop; + } + break; +#endif +#ifdef INET6 + case IPPROTO_IPV6: + af = AF_INET6; + if (m->m_len < sizeof(struct ip6_hdr)) + m = m_pullup(m, sizeof(struct ip6_hdr)); + if (m == NULL) + goto drop; + t = htonl((uint32_t)ecn << 20); + ip6 = mtod(m, struct ip6_hdr *); + if (ip6_ecn_egress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED: + ECN_NOCARE, &t, &ip6->ip6_flow) == 0) { + m_freem(m); + goto drop; + } + break; +#endif + case IPPROTO_ETHERIP: + af = AF_LINK; + break; + default: + m_freem(m); + goto drop; + } + +#ifdef MAC + mac_ifnet_create_mbuf(ifp, m); +#endif + + if (bpf_peers_present(ifp->if_bpf)) { + uint32_t af1 = af; + bpf_mtap2(ifp->if_bpf, &af1, sizeof(af1), m); + } + + if ((ifp->if_flags & IFF_MONITOR) != 0) { + if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); + if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); + m_freem(m); + return; + } + + if (ng_gif_input_p != NULL) { + (*ng_gif_input_p)(ifp, &m, af); + if (m == NULL) + goto drop; + } + + /* + * Put the packet to the network layer input queue according to the + * specified address family. + * Note: older versions of gif_input directly called network layer + * input functions, e.g. ip6_input, here. We changed the policy to + * prevent too many recursive calls of such input functions, which + * might cause kernel panic. But the change may introduce another + * problem; if the input queue is full, packets are discarded. + * The kernel stack overflow really happened, and we believed + * queue-full rarely occurs, so we changed the policy. + */ + switch (af) { +#ifdef INET + case AF_INET: + isr = NETISR_IP; + break; +#endif +#ifdef INET6 + case AF_INET6: + isr = NETISR_IPV6; + break; +#endif + case AF_LINK: + n = sizeof(struct etherip_header) + + sizeof(struct ether_header); + if (n > m->m_len) + m = m_pullup(m, n); + if (m == NULL) + goto drop; + eip = mtod(m, struct etherip_header *); + if (eip->eip_ver != ETHERIP_VERSION) { + /* discard unknown versions */ + m_freem(m); + goto drop; + } + + m_adj_decap(m, sizeof(struct etherip_header)); + + m->m_flags &= ~(M_BCAST|M_MCAST); + m->m_pkthdr.rcvif = ifp; + + if (ifp->if_bridge) { + oldifp = ifp; + eh = mtod(m, struct ether_header *); + if (ETHER_IS_MULTICAST(eh->ether_dhost)) { + if (ETHER_IS_BROADCAST(eh->ether_dhost)) + m->m_flags |= M_BCAST; + else + m->m_flags |= M_MCAST; + if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); + } + BRIDGE_INPUT(ifp, m); + + if (m != NULL && ifp != oldifp) { + /* + * The bridge gave us back itself or one of the + * members for which the frame is addressed. + */ + ether_demux(ifp, m); + return; + } + } + if (m != NULL) + m_freem(m); + return; + + default: + if (ng_gif_input_orphan_p != NULL) + (*ng_gif_input_orphan_p)(ifp, m, af); + else + m_freem(m); + return; + } + + if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); + if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); + M_SETFIB(m, ifp->if_fib); + netisr_dispatch(isr, m); + return; +drop: + if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); +} + +static int +gif_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) +{ + struct ifreq *ifr = (struct ifreq*)data; + struct gif_softc *sc; + u_int options; + int error; + + switch (cmd) { + case SIOCSIFADDR: + ifp->if_flags |= IFF_UP; + case SIOCADDMULTI: + case SIOCDELMULTI: + case SIOCGIFMTU: + case SIOCSIFFLAGS: + return (0); + case SIOCSIFMTU: + if (ifr->ifr_mtu < GIF_MTU_MIN || + ifr->ifr_mtu > GIF_MTU_MAX) + return (EINVAL); + else + ifp->if_mtu = ifr->ifr_mtu; + return (0); + } + sx_xlock(&gif_ioctl_sx); + sc = ifp->if_softc; + if (sc == NULL) { + error = ENXIO; + goto bad; + } + error = 0; + switch (cmd) { + case SIOCDIFPHYADDR: + if (sc->gif_family == 0) + break; + gif_delete_tunnel(sc); + break; +#ifdef INET + case SIOCSIFPHYADDR: + case SIOCGIFPSRCADDR: + case SIOCGIFPDSTADDR: + error = in_gif_ioctl(sc, cmd, data); + break; +#endif +#ifdef INET6 + case SIOCSIFPHYADDR_IN6: + case SIOCGIFPSRCADDR_IN6: + case SIOCGIFPDSTADDR_IN6: + error = in6_gif_ioctl(sc, cmd, data); + break; +#endif + case SIOCGTUNFIB: + ifr->ifr_fib = sc->gif_fibnum; + break; + case SIOCSTUNFIB: + if ((error = priv_check(curthread, PRIV_NET_GIF)) != 0) + break; + if (ifr->ifr_fib >= rt_numfibs) + error = EINVAL; + else + sc->gif_fibnum = ifr->ifr_fib; + break; + case GIFGOPTS: + options = sc->gif_options; + error = copyout(&options, ifr_data_get_ptr(ifr), + sizeof(options)); + break; + case GIFSOPTS: + if ((error = priv_check(curthread, PRIV_NET_GIF)) != 0) + break; + error = copyin(ifr_data_get_ptr(ifr), &options, + sizeof(options)); + if (error) + break; + if (options & ~GIF_OPTMASK) { + error = EINVAL; + break; + } + if (sc->gif_options != options) { + switch (sc->gif_family) { +#ifdef INET + case AF_INET: + error = in_gif_setopts(sc, options); + break; +#endif +#ifdef INET6 + case AF_INET6: + error = in6_gif_setopts(sc, options); + break; +#endif + default: + /* No need to invoke AF-handler */ + sc->gif_options = options; + } + } + break; + default: + error = EINVAL; + break; + } + if (error == 0 && sc->gif_family != 0) { + if ( +#ifdef INET + cmd == SIOCSIFPHYADDR || +#endif +#ifdef INET6 + cmd == SIOCSIFPHYADDR_IN6 || +#endif + 0) { + if_link_state_change(ifp, LINK_STATE_UP); + } + } +bad: + sx_xunlock(&gif_ioctl_sx); + return (error); +} + +static void +gif_delete_tunnel(struct gif_softc *sc) +{ + + sx_assert(&gif_ioctl_sx, SA_XLOCKED); + if (sc->gif_family != 0) { + CK_LIST_REMOVE(sc, srchash); + CK_LIST_REMOVE(sc, chain); + /* Wait until it become safe to free gif_hdr */ + GIF_WAIT(); + free(sc->gif_hdr, M_GIF); + } + sc->gif_family = 0; + GIF2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; + if_link_state_change(GIF2IFP(sc), LINK_STATE_DOWN); +} |