freebsd-src/sys/net/if_infiniband.c
Nicholas Dance 8d079c6a9a if_infininband: Support BPF write for broadcast frames
To support DHCP for IPoIB links, DHCP clients and servers require the
ability to transmit link-layer broadcasts on the IB interfaces. BPF
provides the mechanism for doing this.

This change updates the if_infiniband driver to be capable of accepting
link-layer broadcast requests via BPF using Ethernet formatted frames
(the driver currently registers with BPF as DLT_EN10MB). Only Broadcast
frames can reliably be interpreted using the Ethernet header format so
detect unicast and multicast frames are rejected if passed in using the
Ethernet format. This doesn't impact the ability to support native
unicast, broadcast or multicast frames if native infiniband header
support is added to BPF at a later date.

Further the above, this commit also addresses an issue in the existing
code that can result in separation of part of the packet header from the
rest of the payload if a BPF write was attempted. This was caused by
mbuf preallocation of the infiniband header length regardless of length
of the prepend data.

Reviewed by:	rpokala; Greg Foster <gfoster@vdura.com>
Tested by:	Greg Foster <gfoster@vdura.com>
MFC after:	1 week
Sponsored by:	Vdura
Pull Request:	https://github.com/freebsd/freebsd-src/pull/1591
2025-02-23 16:13:09 -08:00

731 lines
17 KiB
C

/*-
* Copyright (c) 2020 Mellanox Technologies. 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 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 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.
*/
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_kbd.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/devctl.h>
#include <sys/eventhandler.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#ifdef KDB
#include <sys/kdb.h>
#endif
#include <net/bpf.h>
#include <net/ethernet.h>
#include <net/infiniband.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_private.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_lagg.h>
#include <net/if_llatbl.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#include <netinet/if_ether.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <netinet6/in6_var.h>
#include <netinet6/nd6.h>
#include <security/mac/mac_framework.h>
/* if_lagg(4) support */
struct mbuf *(*lagg_input_infiniband_p)(struct ifnet *, struct mbuf *);
#ifdef INET
static inline void
infiniband_ipv4_multicast_map(uint32_t addr,
const uint8_t *broadcast, uint8_t *buf)
{
uint8_t scope;
addr = ntohl(addr);
scope = broadcast[5] & 0xF;
buf[0] = 0;
buf[1] = 0xff;
buf[2] = 0xff;
buf[3] = 0xff;
buf[4] = 0xff;
buf[5] = 0x10 | scope;
buf[6] = 0x40;
buf[7] = 0x1b;
buf[8] = broadcast[8];
buf[9] = broadcast[9];
buf[10] = 0;
buf[11] = 0;
buf[12] = 0;
buf[13] = 0;
buf[14] = 0;
buf[15] = 0;
buf[16] = (addr >> 24) & 0xff;
buf[17] = (addr >> 16) & 0xff;
buf[18] = (addr >> 8) & 0xff;
buf[19] = addr & 0xff;
}
#endif
#ifdef INET6
static inline void
infiniband_ipv6_multicast_map(const struct in6_addr *addr,
const uint8_t *broadcast, uint8_t *buf)
{
uint8_t scope;
scope = broadcast[5] & 0xF;
buf[0] = 0;
buf[1] = 0xff;
buf[2] = 0xff;
buf[3] = 0xff;
buf[4] = 0xff;
buf[5] = 0x10 | scope;
buf[6] = 0x60;
buf[7] = 0x1b;
buf[8] = broadcast[8];
buf[9] = broadcast[9];
memcpy(&buf[10], &addr->s6_addr[6], 10);
}
#endif
/*
* This is for clients that have an infiniband_header in the mbuf.
*/
void
infiniband_bpf_mtap(struct ifnet *ifp, struct mbuf *mb)
{
struct infiniband_header *ibh;
struct ether_header eh;
if (!bpf_peers_present(ifp->if_bpf))
return;
M_ASSERTVALID(mb);
if (mb->m_len < sizeof(*ibh))
return;
ibh = mtod(mb, struct infiniband_header *);
eh.ether_type = ibh->ib_protocol;
memset(eh.ether_shost, 0, ETHER_ADDR_LEN);
memcpy(eh.ether_dhost, ibh->ib_hwaddr + 4, ETHER_ADDR_LEN);
mb->m_data += sizeof(*ibh);
mb->m_len -= sizeof(*ibh);
mb->m_pkthdr.len -= sizeof(*ibh);
bpf_mtap2(ifp->if_bpf, &eh, sizeof(eh), mb);
mb->m_data -= sizeof(*ibh);
mb->m_len += sizeof(*ibh);
mb->m_pkthdr.len += sizeof(*ibh);
}
/*
* For clients using BPF to send broadcasts.
*
* This driver binds to BPF as an EN10MB (Ethernet) device type. As such, it is
* expected BPF and BPF users will send frames with Ethernet headers, which
* we'll do our best to handle. We can't resolve non-native unicast or multicast
* link-layer addresses, but we can handle broadcast frames.
*
* phlen is populated with IB header size if ibh was populated, 0 otherwise.
*/
static int
infiniband_resolve_bpf(struct ifnet *ifp, const struct sockaddr *dst,
struct mbuf *mb, const struct route *ro, struct infiniband_header *ibh,
int *phlen)
{
struct ether_header *eh = (struct ether_header *)ro->ro_prepend;
/* If the prepend data & address length don't have the signature of a frame
* forwarded by BPF, allow frame to passthrough. */
if (((ro->ro_flags & RT_HAS_HEADER) == 0) ||
(ro->ro_plen != ETHER_HDR_LEN)) {
*phlen = 0;
return (0);
}
/* Looks like this frame is from BPF. Handle broadcasts, reject otherwise */
if (!ETHER_IS_BROADCAST(eh->ether_dhost))
return (EOPNOTSUPP);
memcpy(ibh->ib_hwaddr, ifp->if_broadcastaddr, sizeof(ibh->ib_hwaddr));
ibh->ib_protocol = eh->ether_type;
mb->m_flags &= ~M_MCAST;
mb->m_flags |= M_BCAST;
*phlen = INFINIBAND_HDR_LEN;
return (0);
}
static void
update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst)
{
int csum_flags = 0;
if (src->m_pkthdr.csum_flags & CSUM_IP)
csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID);
if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA)
csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR);
if (src->m_pkthdr.csum_flags & CSUM_SCTP)
csum_flags |= CSUM_SCTP_VALID;
dst->m_pkthdr.csum_flags |= csum_flags;
if (csum_flags & CSUM_DATA_VALID)
dst->m_pkthdr.csum_data = 0xffff;
}
/*
* Handle link-layer encapsulation requests.
*/
static int
infiniband_requestencap(struct ifnet *ifp, struct if_encap_req *req)
{
struct infiniband_header *ih;
struct arphdr *ah;
uint16_t etype;
const uint8_t *lladdr;
if (req->rtype != IFENCAP_LL)
return (EOPNOTSUPP);
if (req->bufsize < INFINIBAND_HDR_LEN)
return (ENOMEM);
ih = (struct infiniband_header *)req->buf;
lladdr = req->lladdr;
req->lladdr_off = 0;
switch (req->family) {
case AF_INET:
etype = htons(ETHERTYPE_IP);
break;
case AF_INET6:
etype = htons(ETHERTYPE_IPV6);
break;
case AF_ARP:
ah = (struct arphdr *)req->hdata;
ah->ar_hrd = htons(ARPHRD_INFINIBAND);
switch (ntohs(ah->ar_op)) {
case ARPOP_REVREQUEST:
case ARPOP_REVREPLY:
etype = htons(ETHERTYPE_REVARP);
break;
case ARPOP_REQUEST:
case ARPOP_REPLY:
default:
etype = htons(ETHERTYPE_ARP);
break;
}
if (req->flags & IFENCAP_FLAG_BROADCAST)
lladdr = ifp->if_broadcastaddr;
break;
default:
return (EAFNOSUPPORT);
}
ih->ib_protocol = etype;
ih->ib_reserved = 0;
memcpy(ih->ib_hwaddr, lladdr, INFINIBAND_ADDR_LEN);
req->bufsize = sizeof(struct infiniband_header);
return (0);
}
static int
infiniband_resolve_addr(struct ifnet *ifp, struct mbuf *m,
const struct sockaddr *dst, struct route *ro, uint8_t *phdr,
uint32_t *pflags, struct llentry **plle)
{
#if defined(INET) || defined(INET6)
struct infiniband_header *ih = (struct infiniband_header *)phdr;
#endif
uint32_t lleflags = 0;
int error = 0;
if (plle)
*plle = NULL;
switch (dst->sa_family) {
#ifdef INET
case AF_INET:
if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) {
error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, plle);
} else {
if (m->m_flags & M_BCAST) {
memcpy(ih->ib_hwaddr, ifp->if_broadcastaddr,
INFINIBAND_ADDR_LEN);
} else {
infiniband_ipv4_multicast_map(
((const struct sockaddr_in *)dst)->sin_addr.s_addr,
ifp->if_broadcastaddr, ih->ib_hwaddr);
}
ih->ib_protocol = htons(ETHERTYPE_IP);
ih->ib_reserved = 0;
}
break;
#endif
#ifdef INET6
case AF_INET6:
if ((m->m_flags & M_MCAST) == 0) {
int af = RO_GET_FAMILY(ro, dst);
error = nd6_resolve(ifp, LLE_SF(af, 0), m, dst, phdr,
&lleflags, plle);
} else {
infiniband_ipv6_multicast_map(
&((const struct sockaddr_in6 *)dst)->sin6_addr,
ifp->if_broadcastaddr, ih->ib_hwaddr);
ih->ib_protocol = htons(ETHERTYPE_IPV6);
ih->ib_reserved = 0;
}
break;
#endif
default:
if_printf(ifp, "can't handle af%d\n", dst->sa_family);
if (m != NULL)
m_freem(m);
return (EAFNOSUPPORT);
}
if (error == EHOSTDOWN) {
if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0)
error = EHOSTUNREACH;
}
if (error != 0)
return (error);
*pflags = RT_MAY_LOOP;
if (lleflags & LLE_IFADDR)
*pflags |= RT_L2_ME;
return (0);
}
/*
* Infiniband output routine.
*/
static int
infiniband_output(struct ifnet *ifp, struct mbuf *m,
const struct sockaddr *dst, struct route *ro)
{
uint8_t linkhdr[INFINIBAND_HDR_LEN];
uint8_t *phdr;
struct llentry *lle = NULL;
struct infiniband_header *ih;
int error = 0;
int hlen = 0; /* link layer header length */
uint32_t pflags;
bool addref;
NET_EPOCH_ASSERT();
addref = false;
phdr = NULL;
pflags = 0;
if (ro != NULL) {
/* XXX BPF and ARP use ro_prepend */
if (ro->ro_prepend != NULL) {
ih = (struct infiniband_header *)linkhdr;
/* Assess whether frame is from BPF and handle */
error = infiniband_resolve_bpf(ifp, dst, m, ro, ih, &hlen);
if (error != 0)
goto bad;
if (hlen != 0) {
phdr = linkhdr;
} else {
phdr = ro->ro_prepend;
hlen = ro->ro_plen;
}
} else if (!(m->m_flags & (M_BCAST | M_MCAST))) {
if ((ro->ro_flags & RT_LLE_CACHE) != 0) {
lle = ro->ro_lle;
if (lle != NULL &&
(lle->la_flags & LLE_VALID) == 0) {
LLE_FREE(lle);
lle = NULL; /* redundant */
ro->ro_lle = NULL;
}
if (lle == NULL) {
/* if we lookup, keep cache */
addref = 1;
} else
/*
* Notify LLE code that
* the entry was used
* by datapath.
*/
llentry_provide_feedback(lle);
}
if (lle != NULL) {
phdr = lle->r_linkdata;
hlen = lle->r_hdrlen;
pflags = lle->r_flags;
}
}
}
#ifdef MAC
error = mac_ifnet_check_transmit(ifp, m);
if (error)
goto bad;
#endif
M_PROFILE(m);
if (ifp->if_flags & IFF_MONITOR) {
error = ENETDOWN;
goto bad;
}
if (!((ifp->if_flags & IFF_UP) &&
(ifp->if_drv_flags & IFF_DRV_RUNNING))) {
error = ENETDOWN;
goto bad;
}
if (phdr == NULL) {
/* No prepend data supplied. Try to calculate ourselves. */
phdr = linkhdr;
hlen = INFINIBAND_HDR_LEN;
error = infiniband_resolve_addr(ifp, m, dst, ro, phdr, &pflags,
addref ? &lle : NULL);
if (addref && lle != NULL)
ro->ro_lle = lle;
if (error != 0)
return (error == EWOULDBLOCK ? 0 : error);
}
if ((pflags & RT_L2_ME) != 0) {
update_mbuf_csumflags(m, m);
return (if_simloop(ifp, m, RO_GET_FAMILY(ro, dst), 0));
}
/*
* Add local infiniband header. If no space in first mbuf,
* allocate another.
*/
M_PREPEND(m, hlen, M_NOWAIT);
if (m == NULL) {
error = ENOBUFS;
goto bad;
}
if ((pflags & RT_HAS_HEADER) == 0) {
ih = mtod(m, struct infiniband_header *);
memcpy(ih, phdr, hlen);
}
/*
* Queue message on interface, update output statistics if
* successful, and start output if interface not yet active.
*/
return (ifp->if_transmit(ifp, m));
bad:
if (m != NULL)
m_freem(m);
return (error);
}
/*
* Process a received Infiniband packet.
*/
static void
infiniband_input(struct ifnet *ifp, struct mbuf *m)
{
struct infiniband_header *ibh;
struct epoch_tracker et;
int isr;
bool needs_epoch;
needs_epoch = (ifp->if_flags & IFF_NEEDSEPOCH);
#ifdef INVARIANTS
/*
* This temporary code is here to prevent epoch unaware and unmarked
* drivers to panic the system. Once all drivers are taken care of,
* the whole INVARIANTS block should go away.
*/
if (!needs_epoch && !in_epoch(net_epoch_preempt)) {
static bool printedonce;
needs_epoch = true;
if (!printedonce) {
printedonce = true;
if_printf(ifp, "called %s w/o net epoch! "
"PLEASE file a bug report.", __func__);
#ifdef KDB
kdb_backtrace();
#endif
}
}
#endif
CURVNET_SET_QUIET(ifp->if_vnet);
if (__predict_false(needs_epoch))
NET_EPOCH_ENTER(et);
if ((ifp->if_flags & IFF_UP) == 0) {
if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
m_freem(m);
goto done;
}
ibh = mtod(m, struct infiniband_header *);
/*
* Reset layer specific mbuf flags to avoid confusing upper
* layers:
*/
m->m_flags &= ~M_VLANTAG;
m_clrprotoflags(m);
if (INFINIBAND_IS_MULTICAST(ibh->ib_hwaddr)) {
if (memcmp(ibh->ib_hwaddr, ifp->if_broadcastaddr,
ifp->if_addrlen) == 0)
m->m_flags |= M_BCAST;
else
m->m_flags |= M_MCAST;
if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1);
}
/* Let BPF have it before we strip the header. */
infiniband_bpf_mtap(ifp, m);
/* Allow monitor mode to claim this frame, after stats are updated. */
if (ifp->if_flags & IFF_MONITOR) {
m_freem(m);
goto done;
}
/* Direct packet to correct FIB based on interface config. */
M_SETFIB(m, ifp->if_fib);
/* Handle input from a lagg<N> port */
if (ifp->if_type == IFT_INFINIBANDLAG) {
KASSERT(lagg_input_infiniband_p != NULL,
("%s: if_lagg not loaded!", __func__));
m = (*lagg_input_infiniband_p)(ifp, m);
if (__predict_false(m == NULL))
goto done;
ifp = m->m_pkthdr.rcvif;
}
/*
* Dispatch frame to upper layer.
*/
switch (ibh->ib_protocol) {
#ifdef INET
case htons(ETHERTYPE_IP):
isr = NETISR_IP;
break;
case htons(ETHERTYPE_ARP):
if (ifp->if_flags & IFF_NOARP) {
/* Discard packet if ARP is disabled on interface */
m_freem(m);
goto done;
}
isr = NETISR_ARP;
break;
#endif
#ifdef INET6
case htons(ETHERTYPE_IPV6):
isr = NETISR_IPV6;
break;
#endif
default:
if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
m_freem(m);
goto done;
}
/* Strip off the Infiniband header. */
m_adj(m, INFINIBAND_HDR_LEN);
#ifdef MAC
/*
* Tag the mbuf with an appropriate MAC label before any other
* consumers can get to it.
*/
mac_ifnet_create_mbuf(ifp, m);
#endif
/* Allow monitor mode to claim this frame, after stats are updated. */
netisr_dispatch(isr, m);
done:
if (__predict_false(needs_epoch))
NET_EPOCH_EXIT(et);
CURVNET_RESTORE();
}
static int
infiniband_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa,
struct sockaddr *sa)
{
struct sockaddr_dl *sdl;
#ifdef INET
struct sockaddr_in *sin;
#endif
#ifdef INET6
struct sockaddr_in6 *sin6;
#endif
uint8_t *e_addr;
switch (sa->sa_family) {
case AF_LINK:
/*
* No mapping needed. Just check that it's a valid MC address.
*/
sdl = (struct sockaddr_dl *)sa;
e_addr = LLADDR(sdl);
if (!INFINIBAND_IS_MULTICAST(e_addr))
return (EADDRNOTAVAIL);
*llsa = NULL;
return 0;
#ifdef INET
case AF_INET:
sin = (struct sockaddr_in *)sa;
if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
return (EADDRNOTAVAIL);
sdl = link_init_sdl(ifp, *llsa, IFT_INFINIBAND);
sdl->sdl_alen = INFINIBAND_ADDR_LEN;
e_addr = LLADDR(sdl);
infiniband_ipv4_multicast_map(
sin->sin_addr.s_addr, ifp->if_broadcastaddr, e_addr);
*llsa = (struct sockaddr *)sdl;
return (0);
#endif
#ifdef INET6
case AF_INET6:
sin6 = (struct sockaddr_in6 *)sa;
/*
* An IP6 address of 0 means listen to all of the
* multicast address used for IP6. This has no meaning
* in infiniband.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
return (EADDRNOTAVAIL);
if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
return (EADDRNOTAVAIL);
sdl = link_init_sdl(ifp, *llsa, IFT_INFINIBAND);
sdl->sdl_alen = INFINIBAND_ADDR_LEN;
e_addr = LLADDR(sdl);
infiniband_ipv6_multicast_map(
&sin6->sin6_addr, ifp->if_broadcastaddr, e_addr);
*llsa = (struct sockaddr *)sdl;
return (0);
#endif
default:
return (EAFNOSUPPORT);
}
}
void
infiniband_ifattach(struct ifnet *ifp, const uint8_t *lla, const uint8_t *llb)
{
struct sockaddr_dl *sdl;
struct ifaddr *ifa;
int i;
ifp->if_addrlen = INFINIBAND_ADDR_LEN;
ifp->if_hdrlen = INFINIBAND_HDR_LEN;
ifp->if_mtu = INFINIBAND_MTU;
if_attach(ifp);
ifp->if_output = infiniband_output;
ifp->if_input = infiniband_input;
ifp->if_resolvemulti = infiniband_resolvemulti;
ifp->if_requestencap = infiniband_requestencap;
if (ifp->if_baudrate == 0)
ifp->if_baudrate = IF_Gbps(10); /* default value */
if (llb != NULL)
ifp->if_broadcastaddr = llb;
ifa = ifp->if_addr;
KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__));
sdl = (struct sockaddr_dl *)ifa->ifa_addr;
sdl->sdl_type = IFT_INFINIBAND;
sdl->sdl_alen = ifp->if_addrlen;
if (lla != NULL) {
memcpy(LLADDR(sdl), lla, ifp->if_addrlen);
if (ifp->if_hw_addr != NULL)
memcpy(ifp->if_hw_addr, lla, ifp->if_addrlen);
} else {
lla = LLADDR(sdl);
}
/* Attach ethernet compatible network device */
bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN);
/* Announce Infiniband MAC address if non-zero. */
for (i = 0; i < ifp->if_addrlen; i++)
if (lla[i] != 0)
break;
if (i != ifp->if_addrlen)
if_printf(ifp, "Infiniband address: %20D\n", lla, ":");
/* Add necessary bits are setup; announce it now. */
EVENTHANDLER_INVOKE(infiniband_ifattach_event, ifp);
if (IS_DEFAULT_VNET(curvnet))
devctl_notify("INFINIBAND", ifp->if_xname, "IFATTACH", NULL);
}
/*
* Perform common duties while detaching an Infiniband interface
*/
void
infiniband_ifdetach(struct ifnet *ifp)
{
bpfdetach(ifp);
if_detach(ifp);
}
static int
infiniband_modevent(module_t mod, int type, void *data)
{
switch (type) {
case MOD_LOAD:
case MOD_UNLOAD:
return (0);
default:
return (EOPNOTSUPP);
}
}
static moduledata_t infiniband_mod = {
.name = "if_infiniband",
.evhand = &infiniband_modevent,
};
DECLARE_MODULE(if_infiniband, infiniband_mod, SI_SUB_INIT_IF, SI_ORDER_ANY);
MODULE_VERSION(if_infiniband, 1);