freebsd-skq/sys/net/if_enc.c

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/*-
* 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 <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.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_clone.h>
#include <net/if_types.h>
#include <net/pfil.h>
#include <net/route.h>
#include <net/netisr.h>
#include <net/bpf.h>
Build on Jeff Roberson's linker-set based dynamic per-CPU allocator (DPCPU), as suggested by Peter Wemm, and implement a new per-virtual network stack memory allocator. Modify vnet to use the allocator instead of monolithic global container structures (vinet, ...). This change solves many binary compatibility problems associated with VIMAGE, and restores ELF symbols for virtualized global variables. Each virtualized global variable exists as a "reference copy", and also once per virtual network stack. Virtualized global variables are tagged at compile-time, placing the in a special linker set, which is loaded into a contiguous region of kernel memory. Virtualized global variables in the base kernel are linked as normal, but those in modules are copied and relocated to a reserved portion of the kernel's vnet region with the help of a the kernel linker. Virtualized global variables exist in per-vnet memory set up when the network stack instance is created, and are initialized statically from the reference copy. Run-time access occurs via an accessor macro, which converts from the current vnet and requested symbol to a per-vnet address. When "options VIMAGE" is not compiled into the kernel, normal global ELF symbols will be used instead and indirection is avoided. This change restores static initialization for network stack global variables, restores support for non-global symbols and types, eliminates the need for many subsystem constructors, eliminates large per-subsystem structures that caused many binary compatibility issues both for monitoring applications (netstat) and kernel modules, removes the per-function INIT_VNET_*() macros throughout the stack, eliminates the need for vnet_symmap ksym(2) munging, and eliminates duplicate definitions of virtualized globals under VIMAGE_GLOBALS. Bump __FreeBSD_version and update UPDATING. Portions submitted by: bz Reviewed by: bz, zec Discussed with: gnn, jamie, jeff, jhb, julian, sam Suggested by: peter Approved by: re (kensmith)
2009-07-14 22:48:30 +00:00
#include <net/vnet.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 "opt_inet6.h"
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#endif
#include "opt_enc.h"
#include <netipsec/ipsec.h>
#include <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);
}
}