diff options
Diffstat (limited to 'freebsd/sys/net/if_enc.c')
| -rw-r--r-- | freebsd/sys/net/if_enc.c | 375 |
1 files changed, 375 insertions, 0 deletions
diff --git a/freebsd/sys/net/if_enc.c b/freebsd/sys/net/if_enc.c new file mode 100644 index 00000000..6bbb6ceb --- /dev/null +++ b/freebsd/sys/net/if_enc.c @@ -0,0 +1,375 @@ +#include <freebsd/machine/rtems-bsd-config.h> + +/*- + * Copyright (c) 2006 The FreeBSD Project. + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. + * + * $FreeBSD$ + */ + +#include <freebsd/sys/param.h> +#include <freebsd/sys/systm.h> +#include <freebsd/sys/kernel.h> +#include <freebsd/sys/malloc.h> +#include <freebsd/sys/mbuf.h> +#include <freebsd/sys/module.h> +#include <freebsd/machine/bus.h> +#include <freebsd/sys/rman.h> +#include <freebsd/sys/socket.h> +#include <freebsd/sys/sockio.h> +#include <freebsd/sys/sysctl.h> + +#include <freebsd/net/if.h> +#include <freebsd/net/if_clone.h> +#include <freebsd/net/if_types.h> +#include <freebsd/net/pfil.h> +#include <freebsd/net/route.h> +#include <freebsd/net/netisr.h> +#include <freebsd/net/bpf.h> +#include <freebsd/net/vnet.h> + +#include <freebsd/netinet/in.h> +#include <freebsd/netinet/in_systm.h> +#include <freebsd/netinet/ip.h> +#include <freebsd/netinet/ip_var.h> +#include <freebsd/netinet/in_var.h> +#include <freebsd/local/opt_inet6.h> + +#ifdef INET6 +#include <freebsd/netinet/ip6.h> +#include <freebsd/netinet6/ip6_var.h> +#endif + +#include <freebsd/local/opt_enc.h> +#include <freebsd/netipsec/ipsec.h> +#include <freebsd/netipsec/xform.h> + +#define ENCMTU (1024+512) + +/* XXX this define must have the same value as in OpenBSD */ +#define M_CONF 0x0400 /* payload was encrypted (ESP-transport) */ +#define M_AUTH 0x0800 /* payload was authenticated (AH or ESP auth) */ +#define M_AUTH_AH 0x2000 /* header was authenticated (AH) */ + +struct enchdr { + u_int32_t af; + u_int32_t spi; + u_int32_t flags; +}; + +struct ifnet *encif; +static struct mtx enc_mtx; + +struct enc_softc { + struct ifnet *sc_ifp; +}; + +static int enc_ioctl(struct ifnet *, u_long, caddr_t); +static int enc_output(struct ifnet *ifp, struct mbuf *m, + struct sockaddr *dst, struct route *ro); +static int enc_clone_create(struct if_clone *, int, caddr_t); +static void enc_clone_destroy(struct ifnet *); + +IFC_SIMPLE_DECLARE(enc, 1); + +/* + * Sysctls. + */ + +/* + * Before and after are relative to when we are stripping the + * outer IP header. + */ +SYSCTL_NODE(_net, OID_AUTO, enc, CTLFLAG_RW, 0, "enc sysctl"); + +SYSCTL_NODE(_net_enc, OID_AUTO, in, CTLFLAG_RW, 0, "enc input sysctl"); +static int ipsec_filter_mask_in = ENC_BEFORE; +SYSCTL_XINT(_net_enc_in, OID_AUTO, ipsec_filter_mask, CTLFLAG_RW, + &ipsec_filter_mask_in, 0, "IPsec input firewall filter mask"); +static int ipsec_bpf_mask_in = ENC_BEFORE; +SYSCTL_XINT(_net_enc_in, OID_AUTO, ipsec_bpf_mask, CTLFLAG_RW, + &ipsec_bpf_mask_in, 0, "IPsec input bpf mask"); + +SYSCTL_NODE(_net_enc, OID_AUTO, out, CTLFLAG_RW, 0, "enc output sysctl"); +static int ipsec_filter_mask_out = ENC_BEFORE; +SYSCTL_XINT(_net_enc_out, OID_AUTO, ipsec_filter_mask, CTLFLAG_RW, + &ipsec_filter_mask_out, 0, "IPsec output firewall filter mask"); +static int ipsec_bpf_mask_out = ENC_BEFORE|ENC_AFTER; +SYSCTL_XINT(_net_enc_out, OID_AUTO, ipsec_bpf_mask, CTLFLAG_RW, + &ipsec_bpf_mask_out, 0, "IPsec output bpf mask"); + +static void +enc_clone_destroy(struct ifnet *ifp) +{ + KASSERT(ifp != encif, ("%s: destroying encif", __func__)); + + bpfdetach(ifp); + if_detach(ifp); + if_free(ifp); +} + +static int +enc_clone_create(struct if_clone *ifc, int unit, caddr_t params) +{ + struct ifnet *ifp; + struct enc_softc *sc; + + sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO); + ifp = sc->sc_ifp = if_alloc(IFT_ENC); + if (ifp == NULL) { + free(sc, M_DEVBUF); + return (ENOSPC); + } + + if_initname(ifp, ifc->ifc_name, unit); + ifp->if_mtu = ENCMTU; + ifp->if_ioctl = enc_ioctl; + ifp->if_output = enc_output; + ifp->if_snd.ifq_maxlen = ifqmaxlen; + ifp->if_softc = sc; + if_attach(ifp); + bpfattach(ifp, DLT_ENC, sizeof(struct enchdr)); + + mtx_lock(&enc_mtx); + /* grab a pointer to enc0, ignore the rest */ + if (encif == NULL) + encif = ifp; + mtx_unlock(&enc_mtx); + + return (0); +} + +static int +enc_modevent(module_t mod, int type, void *data) +{ + switch (type) { + case MOD_LOAD: + mtx_init(&enc_mtx, "enc mtx", NULL, MTX_DEF); + if_clone_attach(&enc_cloner); + break; + case MOD_UNLOAD: + printf("enc module unload - not possible for this module\n"); + return (EINVAL); + default: + return (EOPNOTSUPP); + } + return (0); +} + +static moduledata_t enc_mod = { + "enc", + enc_modevent, + 0 +}; + +DECLARE_MODULE(enc, enc_mod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); + +static int +enc_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, + struct route *ro) +{ + m_freem(m); + return (0); +} + +/* + * Process an ioctl request. + */ +/* ARGSUSED */ +static int +enc_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) +{ + int error = 0; + + mtx_lock(&enc_mtx); + + switch (cmd) { + + case SIOCSIFFLAGS: + if (ifp->if_flags & IFF_UP) + ifp->if_drv_flags |= IFF_DRV_RUNNING; + else + ifp->if_drv_flags &= ~IFF_DRV_RUNNING; + + break; + + default: + error = EINVAL; + } + + mtx_unlock(&enc_mtx); + return (error); +} + +int +ipsec_filter(struct mbuf **mp, int dir, int flags) +{ + int error, i; + struct ip *ip; + + KASSERT(encif != NULL, ("%s: encif is null", __func__)); + KASSERT(flags & (ENC_IN|ENC_OUT), + ("%s: invalid flags: %04x", __func__, flags)); + + if ((encif->if_drv_flags & IFF_DRV_RUNNING) == 0) + return (0); + + if (flags & ENC_IN) { + if ((flags & ipsec_filter_mask_in) == 0) + return (0); + } else { + if ((flags & ipsec_filter_mask_out) == 0) + return (0); + } + + /* Skip pfil(9) if no filters are loaded */ + if (!(PFIL_HOOKED(&V_inet_pfil_hook) +#ifdef INET6 + || PFIL_HOOKED(&V_inet6_pfil_hook) +#endif + )) { + return (0); + } + + i = min((*mp)->m_pkthdr.len, max_protohdr); + if ((*mp)->m_len < i) { + *mp = m_pullup(*mp, i); + if (*mp == NULL) { + printf("%s: m_pullup failed\n", __func__); + return (-1); + } + } + + error = 0; + ip = mtod(*mp, struct ip *); + switch (ip->ip_v) { + case 4: + /* + * before calling the firewall, swap fields the same as + * IP does. here we assume the header is contiguous + */ + ip->ip_len = ntohs(ip->ip_len); + ip->ip_off = ntohs(ip->ip_off); + + error = pfil_run_hooks(&V_inet_pfil_hook, mp, + encif, dir, NULL); + + if (*mp == NULL || error != 0) + break; + + /* restore byte ordering */ + ip = mtod(*mp, struct ip *); + ip->ip_len = htons(ip->ip_len); + ip->ip_off = htons(ip->ip_off); + break; + +#ifdef INET6 + case 6: + error = pfil_run_hooks(&V_inet6_pfil_hook, mp, + encif, dir, NULL); + break; +#endif + default: + printf("%s: unknown IP version\n", __func__); + } + + /* + * If the mbuf was consumed by the filter for requeueing (dummynet, etc) + * then error will be zero but we still want to return an error to our + * caller so the null mbuf isn't forwarded further. + */ + if (*mp == NULL && error == 0) + return (-1); /* Consumed by the filter */ + if (*mp == NULL) + return (error); + if (error != 0) + goto bad; + + return (error); + +bad: + m_freem(*mp); + *mp = NULL; + return (error); +} + +void +ipsec_bpf(struct mbuf *m, struct secasvar *sav, int af, int flags) +{ + int mflags; + struct enchdr hdr; + + KASSERT(encif != NULL, ("%s: encif is null", __func__)); + KASSERT(flags & (ENC_IN|ENC_OUT), + ("%s: invalid flags: %04x", __func__, flags)); + + if ((encif->if_drv_flags & IFF_DRV_RUNNING) == 0) + return; + + if (flags & ENC_IN) { + if ((flags & ipsec_bpf_mask_in) == 0) + return; + } else { + if ((flags & ipsec_bpf_mask_out) == 0) + return; + } + + if (bpf_peers_present(encif->if_bpf)) { + mflags = 0; + hdr.spi = 0; + if (!sav) { + struct m_tag *mtag; + mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); + if (mtag != NULL) { + struct tdb_ident *tdbi; + tdbi = (struct tdb_ident *) (mtag + 1); + if (tdbi->alg_enc != SADB_EALG_NONE) + mflags |= M_CONF; + if (tdbi->alg_auth != SADB_AALG_NONE) + mflags |= M_AUTH; + hdr.spi = tdbi->spi; + } + } else { + if (sav->alg_enc != SADB_EALG_NONE) + mflags |= M_CONF; + if (sav->alg_auth != SADB_AALG_NONE) + mflags |= M_AUTH; + hdr.spi = sav->spi; + } + + /* + * We need to prepend the address family as a four byte + * field. Cons up a dummy header to pacify bpf. This + * is safe because bpf will only read from the mbuf + * (i.e., it won't try to free it or keep a pointer a + * to it). + */ + hdr.af = af; + /* hdr.spi already set above */ + hdr.flags = mflags; + + bpf_mtap2(encif->if_bpf, &hdr, sizeof(hdr), m); + } +} |