diff options
Diffstat (limited to 'sys/net/if_disc.c')
| -rw-r--r-- | sys/net/if_disc.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/sys/net/if_disc.c b/sys/net/if_disc.c new file mode 100644 index 000000000000..bafa676c941c --- /dev/null +++ b/sys/net/if_disc.c @@ -0,0 +1,239 @@ +/*- + * 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. + */ + +/* + * Discard interface driver for protocol testing and timing. + * (Based on the loopback.) + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/module.h> +#include <sys/mbuf.h> +#include <sys/socket.h> +#include <sys/sockio.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/route.h> +#include <net/bpf.h> +#include <net/vnet.h> + +#include "opt_inet.h" +#include "opt_inet6.h" + +#ifdef TINY_DSMTU +#define DSMTU (1024+512) +#else +#define DSMTU 65532 +#endif + +struct disc_softc { + struct ifnet *sc_ifp; +}; + +static int discoutput(struct ifnet *, struct mbuf *, + const struct sockaddr *, struct route *); +static int discioctl(struct ifnet *, u_long, caddr_t); +static int disc_clone_create(struct if_clone *, int, caddr_t); +static void disc_clone_destroy(struct ifnet *); + +static const char discname[] = "disc"; +static MALLOC_DEFINE(M_DISC, discname, "Discard interface"); + +VNET_DEFINE_STATIC(struct if_clone *, disc_cloner); +#define V_disc_cloner VNET(disc_cloner) + +static int +disc_clone_create(struct if_clone *ifc, int unit, caddr_t params) +{ + struct ifnet *ifp; + struct disc_softc *sc; + + sc = malloc(sizeof(struct disc_softc), M_DISC, M_WAITOK | M_ZERO); + ifp = sc->sc_ifp = if_alloc(IFT_LOOP); + ifp->if_softc = sc; + if_initname(ifp, discname, unit); + ifp->if_mtu = DSMTU; + /* + * IFF_LOOPBACK should not be removed from disc's flags because + * it controls what PF-specific routes are magically added when + * a network address is assigned to the interface. Things just + * won't work as intended w/o such routes because the output + * interface selection for a packet is totally route-driven. + * A valid alternative to IFF_LOOPBACK can be IFF_BROADCAST or + * IFF_POINTOPOINT, but it would result in different properties + * of the interface. + */ + ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; + ifp->if_drv_flags = IFF_DRV_RUNNING; + ifp->if_ioctl = discioctl; + ifp->if_output = discoutput; + ifp->if_hdrlen = 0; + ifp->if_addrlen = 0; + ifp->if_snd.ifq_maxlen = 20; + if_attach(ifp); + bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); + + return (0); +} + +static void +disc_clone_destroy(struct ifnet *ifp) +{ + struct disc_softc *sc; + + sc = ifp->if_softc; + + bpfdetach(ifp); + if_detach(ifp); + if_free(ifp); + + free(sc, M_DISC); +} + +static void +vnet_disc_init(const void *unused __unused) +{ + + V_disc_cloner = if_clone_simple(discname, disc_clone_create, + disc_clone_destroy, 0); +} +VNET_SYSINIT(vnet_disc_init, SI_SUB_PSEUDO, SI_ORDER_ANY, + vnet_disc_init, NULL); + +static void +vnet_disc_uninit(const void *unused __unused) +{ + + if_clone_detach(V_disc_cloner); +} +VNET_SYSUNINIT(vnet_disc_uninit, SI_SUB_INIT_IF, SI_ORDER_ANY, + vnet_disc_uninit, NULL); + +static int +disc_modevent(module_t mod, int type, void *data) +{ + + switch (type) { + case MOD_LOAD: + case MOD_UNLOAD: + break; + default: + return (EOPNOTSUPP); + } + return (0); +} + +static moduledata_t disc_mod = { + "if_disc", + disc_modevent, + NULL +}; + +DECLARE_MODULE(if_disc, disc_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); + +static int +discoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, + struct route *ro) +{ + u_int32_t af; + + M_ASSERTPKTHDR(m); + + /* 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 (bpf_peers_present(ifp->if_bpf)) + bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); + + m->m_pkthdr.rcvif = ifp; + + if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); + if_inc_counter(ifp, IFCOUNTER_OBYTES, m->m_pkthdr.len); + + m_freem(m); + return (0); +} + +/* + * Process an ioctl request. + */ +static int +discioctl(struct ifnet *ifp, u_long cmd, caddr_t data) +{ + struct ifreq *ifr = (struct ifreq *)data; + int error = 0; + + switch (cmd) { + case SIOCSIFADDR: + ifp->if_flags |= IFF_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; + default: + error = EINVAL; + } + return (error); +} |