diff options
Diffstat (limited to 'sys/net/if_loop.c')
| -rw-r--r-- | sys/net/if_loop.c | 446 |
1 files changed, 446 insertions, 0 deletions
diff --git a/sys/net/if_loop.c b/sys/net/if_loop.c new file mode 100644 index 000000000000..3005965a4fcb --- /dev/null +++ b/sys/net/if_loop.c @@ -0,0 +1,446 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1982, 1986, 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. 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. + */ + +/* + * Loopback interface driver for protocol testing and timing. + */ + +#include "opt_inet.h" +#include "opt_inet6.h" +#include "opt_rss.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/mbuf.h> +#include <sys/module.h> +#include <machine/bus.h> +#include <sys/rman.h> +#include <sys/socket.h> +#include <sys/sockio.h> +#include <sys/sysctl.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> + +#ifdef INET +#include <netinet/in.h> +#include <netinet/in_var.h> +#endif + +#ifdef INET6 +#ifndef INET +#include <netinet/in.h> +#endif +#include <netinet6/in6_var.h> +#include <netinet/ip6.h> +#endif + +#include <security/mac/mac_framework.h> + +#ifdef TINY_LOMTU +#define LOMTU (1024+512) +#elif defined(LARGE_LOMTU) +#define LOMTU 131072 +#else +#define LOMTU 16384 +#endif + +#define LO_CSUM_FEATURES (CSUM_IP | CSUM_TCP | CSUM_UDP | CSUM_SCTP) +#define LO_CSUM_FEATURES6 (CSUM_TCP_IPV6 | CSUM_UDP_IPV6 | CSUM_SCTP_IPV6) +#define LO_CSUM_SET (CSUM_DATA_VALID | CSUM_DATA_VALID_IPV6 | \ + CSUM_PSEUDO_HDR | \ + CSUM_IP_CHECKED | CSUM_IP_VALID | \ + CSUM_SCTP_VALID) + +static int loioctl(struct ifnet *, u_long, caddr_t); +static int looutput(struct ifnet *ifp, struct mbuf *m, + const struct sockaddr *dst, struct route *ro); + +VNET_DEFINE(struct ifnet *, loif); /* Used externally */ +VNET_DEFINE_STATIC(struct if_clone *, lo_cloner); +#define V_lo_cloner VNET(lo_cloner) + +static const char loname[] = "lo"; + +static int +lo_clone_destroy(struct if_clone *ifc, struct ifnet *ifp, uint32_t flags) +{ + if (ifp->if_dunit == 0 && (flags & IFC_F_FORCE) == 0) + return (EINVAL); + +#ifndef VIMAGE + /* XXX: destroying lo0 will lead to panics. */ + KASSERT(V_loif != ifp, ("%s: destroying lo0", __func__)); +#endif + + bpfdetach(ifp); + if_detach(ifp); + if_free(ifp); + + return (0); +} + +static int +lo_clone_create(struct if_clone *ifc, char *name, size_t len, + struct ifc_data *ifd, struct ifnet **ifpp) +{ + struct ifnet *ifp; + + ifp = if_alloc(IFT_LOOP); + if_initname(ifp, loname, ifd->unit); + ifp->if_mtu = LOMTU; + ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; + ifp->if_ioctl = loioctl; + ifp->if_output = looutput; + ifp->if_snd.ifq_maxlen = ifqmaxlen; + ifp->if_capabilities = ifp->if_capenable = + IFCAP_HWCSUM | IFCAP_HWCSUM_IPV6 | IFCAP_LINKSTATE; + ifp->if_hwassist = LO_CSUM_FEATURES | LO_CSUM_FEATURES6; + if_attach(ifp); + bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); + *ifpp = ifp; + + return (0); +} + +static void +vnet_loif_init(const void *unused __unused) +{ + struct if_clone_addreq req = { + .create_f = lo_clone_create, + .destroy_f = lo_clone_destroy, + .flags = IFC_F_AUTOUNIT, + }; + V_lo_cloner = ifc_attach_cloner(loname, &req); + struct ifc_data ifd = { .unit = 0 }; + ifc_create_ifp(loname, &ifd, &V_loif); +} +VNET_SYSINIT(vnet_loif_init, SI_SUB_PSEUDO, SI_ORDER_ANY, + vnet_loif_init, NULL); + +#ifdef VIMAGE +static void +vnet_loif_uninit(const void *unused __unused) +{ + + ifc_detach_cloner(V_lo_cloner); + V_loif = NULL; +} +VNET_SYSUNINIT(vnet_loif_uninit, SI_SUB_INIT_IF, SI_ORDER_SECOND, + vnet_loif_uninit, NULL); +#endif + +static int +loop_modevent(module_t mod, int type, void *data) +{ + + switch (type) { + case MOD_LOAD: + break; + + case MOD_UNLOAD: + printf("loop module unload - not possible for this module type\n"); + return (EINVAL); + + default: + return (EOPNOTSUPP); + } + return (0); +} + +static moduledata_t loop_mod = { + "if_lo", + loop_modevent, + 0 +}; + +DECLARE_MODULE(if_lo, loop_mod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); + +static int +looutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, + struct route *ro) +{ + u_int32_t af; +#ifdef MAC + int error; +#endif + + M_ASSERTPKTHDR(m); /* check if we have the packet header */ + +#ifdef MAC + error = mac_ifnet_check_transmit(ifp, m); + if (error) { + m_freem(m); + return (error); + } +#endif + + if (ro != NULL && ro->ro_flags & (RT_REJECT|RT_BLACKHOLE)) { + m_freem(m); + return (ro->ro_flags & RT_BLACKHOLE ? 0 : EHOSTUNREACH); + } + + if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); + if_inc_counter(ifp, IFCOUNTER_OBYTES, m->m_pkthdr.len); + +#ifdef RSS + M_HASHTYPE_CLEAR(m); +#endif + + /* BPF writes need to be handled specially. */ + if (dst->sa_family == AF_UNSPEC || dst->sa_family == pseudo_AF_HDRCMPLT) + bcopy(dst->sa_data, &af, sizeof(af)); + else + af = RO_GET_FAMILY(ro, dst); + +#if 1 /* XXX */ + switch (af) { + case AF_INET: + if (ifp->if_capenable & IFCAP_RXCSUM) { + m->m_pkthdr.csum_data = 0xffff; + m->m_pkthdr.csum_flags = LO_CSUM_SET; + } + m->m_pkthdr.csum_flags &= ~LO_CSUM_FEATURES; + break; + case AF_INET6: +#if 0 + /* + * XXX-BZ for now always claim the checksum is good despite + * any interface flags. This is a workaround for 9.1-R and + * a proper solution ought to be sought later. + */ + if (ifp->if_capenable & IFCAP_RXCSUM_IPV6) { + m->m_pkthdr.csum_data = 0xffff; + m->m_pkthdr.csum_flags = LO_CSUM_SET; + } +#else + m->m_pkthdr.csum_data = 0xffff; + m->m_pkthdr.csum_flags = LO_CSUM_SET; +#endif + m->m_pkthdr.csum_flags &= ~LO_CSUM_FEATURES6; + break; + default: + printf("looutput: af=%d unexpected\n", af); + m_freem(m); + return (EAFNOSUPPORT); + } +#endif + return (if_simloop(ifp, m, af, 0)); +} + +/* + * if_simloop() + * + * This function is to support software emulation of hardware loopback, + * i.e., for interfaces with the IFF_SIMPLEX attribute. Since they can't + * hear their own broadcasts, we create a copy of the packet that we + * would normally receive via a hardware loopback. + * + * This function expects the packet to include the media header of length hlen. + */ +int +if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen) +{ + int isr; + + M_ASSERTPKTHDR(m); + m_tag_delete_nonpersistent(m); + m->m_pkthdr.rcvif = ifp; + +#ifdef MAC + mac_ifnet_create_mbuf(ifp, m); +#endif + + /* + * Let BPF see incoming packet in the following manner: + * - Emulated packet loopback for a simplex interface + * (net/if_ethersubr.c) + * -> passes it to ifp's BPF + * - IPv4/v6 multicast packet loopback (netinet(6)/ip(6)_output.c) + * -> not passes it to any BPF + * - Normal packet loopback from myself to myself (net/if_loop.c) + * -> passes to lo0's BPF (even in case of IPv6, where ifp!=lo0) + */ + if (hlen > 0) { + if (bpf_peers_present(ifp->if_bpf)) { + bpf_mtap(ifp->if_bpf, m); + } + } else { + if (bpf_peers_present(V_loif->if_bpf)) { + if ((m->m_flags & M_MCAST) == 0 || V_loif == ifp) { + /* XXX beware sizeof(af) != 4 */ + u_int32_t af1 = af; + + /* + * We need to prepend the address family. + */ + bpf_mtap2(V_loif->if_bpf, &af1, sizeof(af1), m); + } + } + } + + /* Strip away media header */ + if (hlen > 0) { + m_adj(m, hlen); +#ifndef __NO_STRICT_ALIGNMENT + /* + * Some archs do not like unaligned data, so + * we move data down in the first mbuf. + */ + if (mtod(m, vm_offset_t) & 3) { + KASSERT(hlen >= 3, ("if_simloop: hlen too small")); + bcopy(m->m_data, + (char *)(mtod(m, vm_offset_t) + - (mtod(m, vm_offset_t) & 3)), + m->m_len); + m->m_data -= (mtod(m,vm_offset_t) & 3); + } +#endif + } + + /* Deliver to upper layer protocol */ + switch (af) { +#ifdef INET + case AF_INET: + isr = NETISR_IP; + break; +#endif +#ifdef INET6 + case AF_INET6: + m->m_flags |= M_LOOP; + isr = NETISR_IPV6; + break; +#endif + default: + printf("if_simloop: can't handle af=%d\n", af); + m_freem(m); + return (EAFNOSUPPORT); + } + if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); + if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); + netisr_queue(isr, m); /* mbuf is free'd on failure. */ + return (0); +} + +/* + * Process an ioctl request. + */ +static int +loioctl(struct ifnet *ifp, u_long cmd, caddr_t data) +{ + struct ifreq *ifr = (struct ifreq *)data; + int error = 0, mask; + + switch (cmd) { + case SIOCSIFADDR: + ifp->if_flags |= IFF_UP; + ifp->if_drv_flags |= IFF_DRV_RUNNING; + if_link_state_change(ifp, LINK_STATE_UP); + /* + * Everything else is done at a higher level. + */ + break; + + case SIOCADDMULTI: + case SIOCDELMULTI: + if (ifr == NULL) { + error = EAFNOSUPPORT; /* XXX */ + 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 SIOCSIFMTU: + ifp->if_mtu = ifr->ifr_mtu; + break; + + case SIOCSIFFLAGS: + if_link_state_change(ifp, (ifp->if_flags & IFF_UP) ? + LINK_STATE_UP: LINK_STATE_DOWN); + break; + + case SIOCSIFCAP: + mask = ifp->if_capenable ^ ifr->ifr_reqcap; + if ((mask & IFCAP_RXCSUM) != 0) + ifp->if_capenable ^= IFCAP_RXCSUM; + if ((mask & IFCAP_TXCSUM) != 0) + ifp->if_capenable ^= IFCAP_TXCSUM; + if ((mask & IFCAP_RXCSUM_IPV6) != 0) { +#if 0 + ifp->if_capenable ^= IFCAP_RXCSUM_IPV6; +#else + error = EOPNOTSUPP; + break; +#endif + } + if ((mask & IFCAP_TXCSUM_IPV6) != 0) { +#if 0 + ifp->if_capenable ^= IFCAP_TXCSUM_IPV6; +#else + error = EOPNOTSUPP; + break; +#endif + } + ifp->if_hwassist = 0; + if (ifp->if_capenable & IFCAP_TXCSUM) + ifp->if_hwassist = LO_CSUM_FEATURES; +#if 0 + if (ifp->if_capenable & IFCAP_TXCSUM_IPV6) + ifp->if_hwassist |= LO_CSUM_FEATURES6; +#endif + break; + + default: + error = EINVAL; + } + return (error); +} |