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freebsd/sys/net/if_atmsubr.c
Archie Cobbs 2127f26023 Examine all occurrences of sprintf(), strcat(), and str[n]cpy()
for possible buffer overflow problems. Replaced most sprintf()'s
with snprintf(); for others cases, added terminating NUL bytes where
appropriate, replaced constants like "16" with sizeof(), etc.

These changes include several bug fixes, but most changes are for
maintainability's sake. Any instance where it wasn't "immediately
obvious" that a buffer overflow could not occur was made safer.

Reviewed by:	Bruce Evans <bde@zeta.org.au>
Reviewed by:	Matthew Dillon <dillon@apollo.backplane.com>
Reviewed by:	Mike Spengler <mks@networkcs.com>
1998-12-04 22:54:57 +00:00

630 lines
15 KiB
C

/* $NetBSD: if_atmsubr.c,v 1.10 1997/03/11 23:19:51 chuck Exp $ */
/*
*
* Copyright (c) 1996 Charles D. Cranor and Washington University.
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Charles D. Cranor and
* Washington University.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
/*
* if_atmsubr.c
*/
#include "opt_inet.h"
#include "opt_natm.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/malloc.h>
#include <sys/errno.h>
#include <net/if.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/if_atm.h>
#include <netinet/in.h>
#include <netinet/if_atm.h>
#include <netinet/if_ether.h> /* XXX: for ETHERTYPE_* */
#if defined(INET) || defined(INET6)
#include <netinet/in_var.h>
#endif
#ifdef NATM
#include <netnatm/natm.h>
#endif
#ifndef ETHERTYPE_IPV6
#define ETHERTYPE_IPV6 0x86dd
#endif
#define senderr(e) { error = (e); goto bad;}
/*
* atm_output: ATM output routine
* inputs:
* "ifp" = ATM interface to output to
* "m0" = the packet to output
* "dst" = the sockaddr to send to (either IP addr, or raw VPI/VCI)
* "rt0" = the route to use
* returns: error code [0 == ok]
*
* note: special semantic: if (dst == NULL) then we assume "m" already
* has an atm_pseudohdr on it and just send it directly.
* [for native mode ATM output] if dst is null, then
* rt0 must also be NULL.
*/
int
atm_output(ifp, m0, dst, rt0)
register struct ifnet *ifp;
struct mbuf *m0;
struct sockaddr *dst;
struct rtentry *rt0;
{
u_int16_t etype = 0; /* if using LLC/SNAP */
int s, error = 0, sz;
struct atm_pseudohdr atmdst, *ad;
register struct mbuf *m = m0;
register struct rtentry *rt;
struct atmllc *atmllc;
struct atmllc *llc_hdr = NULL;
u_int32_t atm_flags;
if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
senderr(ENETDOWN);
/*
* check route
*/
if ((rt = rt0) != NULL) {
if ((rt->rt_flags & RTF_UP) == 0) { /* route went down! */
if ((rt0 = rt = RTALLOC1(dst, 0)) != NULL)
rt->rt_refcnt--;
else
senderr(EHOSTUNREACH);
}
if (rt->rt_flags & RTF_GATEWAY) {
if (rt->rt_gwroute == 0)
goto lookup;
if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
rtfree(rt); rt = rt0;
lookup: rt->rt_gwroute = RTALLOC1(rt->rt_gateway, 0);
if ((rt = rt->rt_gwroute) == 0)
senderr(EHOSTUNREACH);
}
}
/* XXX: put RTF_REJECT code here if doing ATMARP */
}
/*
* check for non-native ATM traffic (dst != NULL)
*/
if (dst) {
switch (dst->sa_family) {
#if defined(INET) || defined(INET6)
case AF_INET:
case AF_INET6:
if (!atmresolve(rt, m, dst, &atmdst)) {
m = NULL;
/* XXX: atmresolve already free'd it */
senderr(EHOSTUNREACH);
/* XXX: put ATMARP stuff here */
/* XXX: watch who frees m on failure */
}
if (dst->sa_family == AF_INET6)
etype = htons(ETHERTYPE_IPV6);
else
etype = htons(ETHERTYPE_IP);
break;
#endif /* INET || INET6 */
case AF_UNSPEC:
/*
* XXX: bpfwrite or output from a pvc shadow if.
* assuming dst contains 12 bytes (atm pseudo
* header (4) + LLC/SNAP (8))
*/
bcopy(dst->sa_data, &atmdst, sizeof(atmdst));
llc_hdr = (struct atmllc *)(dst->sa_data + sizeof(atmdst));
break;
default:
#if defined(__NetBSD__) || defined(__OpenBSD__)
printf("%s: can't handle af%d\n", ifp->if_xname,
dst->sa_family);
#elif defined(__FreeBSD__) || defined(__bsdi__)
printf("%s%d: can't handle af%d\n", ifp->if_name,
ifp->if_unit, dst->sa_family);
#endif
senderr(EAFNOSUPPORT);
}
/*
* must add atm_pseudohdr to data
*/
sz = sizeof(atmdst);
atm_flags = ATM_PH_FLAGS(&atmdst);
if (atm_flags & ATM_PH_LLCSNAP) sz += 8; /* sizeof snap == 8 */
M_PREPEND(m, sz, M_DONTWAIT);
if (m == 0)
senderr(ENOBUFS);
ad = mtod(m, struct atm_pseudohdr *);
*ad = atmdst;
if (atm_flags & ATM_PH_LLCSNAP) {
atmllc = (struct atmllc *)(ad + 1);
if (llc_hdr == NULL) {
bcopy(ATMLLC_HDR, atmllc->llchdr,
sizeof(atmllc->llchdr));
ATM_LLC_SETTYPE(atmllc, etype);
/* note: already in network order */
}
else
bcopy(llc_hdr, atmllc, sizeof(struct atmllc));
}
}
/*
* Queue message on interface, and start output if interface
* not yet active.
*/
s = splimp();
if (IF_QFULL(&ifp->if_snd)) {
IF_DROP(&ifp->if_snd);
splx(s);
senderr(ENOBUFS);
}
ifp->if_obytes += m->m_pkthdr.len;
IF_ENQUEUE(&ifp->if_snd, m);
if ((ifp->if_flags & IFF_OACTIVE) == 0)
(*ifp->if_start)(ifp);
splx(s);
return (error);
bad:
if (m)
m_freem(m);
return (error);
}
/*
* Process a received ATM packet;
* the packet is in the mbuf chain m.
*/
void
atm_input(ifp, ah, m, rxhand)
struct ifnet *ifp;
register struct atm_pseudohdr *ah;
struct mbuf *m;
void *rxhand;
{
register struct ifqueue *inq;
u_int16_t etype = ETHERTYPE_IP; /* default */
int s;
if ((ifp->if_flags & IFF_UP) == 0) {
m_freem(m);
return;
}
ifp->if_ibytes += m->m_pkthdr.len;
#ifdef ATM_PVCEXT
if (ATM_PH_FLAGS(ah) & ATM_PH_PVCSIF) {
/*
* when PVC shadow interface is used, pointer to
* the shadow interface is passed as rxhand.
* override the receive interface of the packet.
*/
m->m_pkthdr.rcvif = (struct ifnet *)rxhand;
rxhand = NULL;
}
#endif /* ATM_PVCEXT */
if (rxhand) {
#ifdef NATM
struct natmpcb *npcb = rxhand;
s = splimp(); /* in case 2 atm cards @ diff lvls */
npcb->npcb_inq++; /* count # in queue */
splx(s);
schednetisr(NETISR_NATM);
inq = &natmintrq;
m->m_pkthdr.rcvif = rxhand; /* XXX: overload */
#else
printf("atm_input: NATM detected but not configured in kernel\n");
m_freem(m);
return;
#endif
} else {
/*
* handle LLC/SNAP header, if present
*/
if (ATM_PH_FLAGS(ah) & ATM_PH_LLCSNAP) {
struct atmllc *alc;
if (m->m_len < sizeof(*alc) &&
(m = m_pullup(m, sizeof(*alc))) == 0)
return; /* failed */
alc = mtod(m, struct atmllc *);
if (bcmp(alc, ATMLLC_HDR, 6)) {
#if defined(__NetBSD__) || defined(__OpenBSD__)
printf("%s: recv'd invalid LLC/SNAP frame [vp=%d,vc=%d]\n",
ifp->if_xname, ATM_PH_VPI(ah), ATM_PH_VCI(ah));
#elif defined(__FreeBSD__) || defined(__bsdi__)
printf("%s%d: recv'd invalid LLC/SNAP frame [vp=%d,vc=%d]\n",
ifp->if_name, ifp->if_unit, ATM_PH_VPI(ah), ATM_PH_VCI(ah));
#endif
m_freem(m);
return;
}
etype = ATM_LLC_TYPE(alc);
m_adj(m, sizeof(*alc));
}
switch (etype) {
#ifdef INET
case ETHERTYPE_IP:
schednetisr(NETISR_IP);
inq = &ipintrq;
break;
#endif
#ifdef INET6
case ETHERTYPE_IPV6:
schednetisr(NETISR_IPV6);
inq = &ip6intrq;
break;
#endif
default:
m_freem(m);
return;
}
}
s = splimp();
if (IF_QFULL(inq)) {
IF_DROP(inq);
m_freem(m);
} else
IF_ENQUEUE(inq, m);
splx(s);
}
/*
* Perform common duties while attaching to interface list
*/
void
atm_ifattach(ifp)
register struct ifnet *ifp;
{
register struct ifaddr *ifa;
register struct sockaddr_dl *sdl;
ifp->if_type = IFT_ATM;
ifp->if_addrlen = 0;
ifp->if_hdrlen = 0;
ifp->if_mtu = ATMMTU;
ifp->if_output = atm_output;
#if defined(__NetBSD__) || defined(__OpenBSD__)
for (ifa = ifp->if_addrlist.tqh_first; ifa != 0;
ifa = ifa->ifa_list.tqe_next)
#elif defined(__FreeBSD__) && (__FreeBSD__ > 2)
for (ifa = ifp->if_addrhead.tqh_first; ifa;
ifa = ifa->ifa_link.tqe_next)
#elif defined(__FreeBSD__) || defined(__bsdi__)
for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#endif
if ((sdl = (struct sockaddr_dl *)ifa->ifa_addr) &&
sdl->sdl_family == AF_LINK) {
sdl->sdl_type = IFT_ATM;
sdl->sdl_alen = ifp->if_addrlen;
#ifdef notyet /* if using ATMARP, store hardware address using the next line */
bcopy(ifp->hw_addr, LLADDR(sdl), ifp->if_addrlen);
#endif
break;
}
}
#ifdef ATM_PVCEXT
/*
* ATM PVC shadow interface: a trick to assign a shadow interface
* to a PVC.
* with shadow interface, each PVC looks like an individual
* Point-to-Point interface.
* as oposed to the NBMA model, a shadow interface is inherently
* multicast capable (no LANE/MARS required).
*/
struct pvcsif {
struct ifnet sif_shadow; /* shadow ifnet structure per pvc */
struct atm_pseudohdr sif_aph; /* flags + vpi:vci */
struct ifnet *sif_ifp; /* pointer to the genuine interface */
};
static int pvc_output __P((struct ifnet *, struct mbuf *,
struct sockaddr *, struct rtentry *));
static int pvc_ioctl __P((struct ifnet *, u_long, caddr_t));
/*
* create and attach per pvc shadow interface
* (currently detach is not supported)
*/
static int pvc_number = 0;
struct ifnet *
pvc_attach(ifp)
struct ifnet *ifp;
{
struct pvcsif *pvcsif;
struct ifnet *shadow;
struct ifaddr *ifa;
struct sockaddr_dl *sdl;
int s;
MALLOC(pvcsif, struct pvcsif *, sizeof(struct pvcsif),
M_DEVBUF, M_WAITOK);
bzero(pvcsif, sizeof(struct pvcsif));
pvcsif->sif_ifp = ifp;
shadow = &pvcsif->sif_shadow;
shadow->if_name = "pvc";
shadow->if_unit = pvc_number++;
shadow->if_flags = ifp->if_flags | (IFF_POINTOPOINT | IFF_MULTICAST);
shadow->if_ioctl = pvc_ioctl;
shadow->if_output = pvc_output;
shadow->if_start = NULL;
shadow->if_mtu = ifp->if_mtu;
shadow->if_type = ifp->if_type;
shadow->if_addrlen = ifp->if_addrlen;
shadow->if_hdrlen = ifp->if_hdrlen;
shadow->if_softc = pvcsif;
shadow->if_snd.ifq_maxlen = 50; /* dummy */
s = splimp();
if_attach(shadow);
#if defined(__NetBSD__) || defined(__OpenBSD__)
for (ifa = shadow->if_addrlist.tqh_first; ifa != 0;
ifa = ifa->ifa_list.tqe_next)
#elif defined(__FreeBSD__) && (__FreeBSD__ > 2)
for (ifa = shadow->if_addrhead.tqh_first; ifa;
ifa = ifa->ifa_link.tqe_next)
#elif defined(__FreeBSD__) || defined(__bsdi__)
for (ifa = shadow->if_addrlist; ifa; ifa = ifa->ifa_next)
#endif
if ((sdl = (struct sockaddr_dl *)ifa->ifa_addr) &&
sdl->sdl_family == AF_LINK) {
sdl->sdl_type = IFT_ATM;
sdl->sdl_alen = shadow->if_addrlen;
break;
}
splx(s);
return (shadow);
}
/*
* pvc_output relays the packet to atm_output along with vpi:vci info.
*/
static int
pvc_output(shadow, m, dst, rt)
struct ifnet *shadow;
struct mbuf *m;
struct sockaddr *dst;
struct rtentry *rt;
{
struct pvcsif *pvcsif;
struct sockaddr dst_addr;
struct atmllc *atmllc;
u_int16_t etype = 0;
int error = 0;
if ((shadow->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
senderr(ENETDOWN);
pvcsif = shadow->if_softc;
if (ATM_PH_VCI(&pvcsif->sif_aph) == 0)
senderr(ENETDOWN);
/*
* create a dummy sockaddr: (using bpfwrite interface)
* put atm pseudo header and llc/snap into sa_data (12 bytes)
* and mark it as AF_UNSPEC.
*/
if (dst) {
switch (dst->sa_family) {
#if defined(INET) || defined(INET6)
case AF_INET:
case AF_INET6:
if (dst->sa_family == AF_INET6)
etype = htons(ETHERTYPE_IPV6);
else
etype = htons(ETHERTYPE_IP);
break;
#endif
default:
printf("%s%d: can't handle af%d\n", shadow->if_name,
shadow->if_unit, dst->sa_family);
senderr(EAFNOSUPPORT);
}
}
dst_addr.sa_family = AF_UNSPEC;
bcopy(&pvcsif->sif_aph, dst_addr.sa_data,
sizeof(struct atm_pseudohdr));
atmllc = (struct atmllc *)
(dst_addr.sa_data + sizeof(struct atm_pseudohdr));
bcopy(ATMLLC_HDR, atmllc->llchdr, sizeof(atmllc->llchdr));
ATM_LLC_SETTYPE(atmllc, etype); /* note: already in network order */
return atm_output(pvcsif->sif_ifp, m, &dst_addr, rt);
bad:
if (m)
m_freem(m);
return (error);
}
static int
pvc_ioctl(shadow, cmd, data)
struct ifnet *shadow;
u_long cmd;
caddr_t data;
{
struct ifnet *ifp;
struct pvcsif *pvcsif;
struct ifreq *ifr = (struct ifreq *) data;
void (*ifa_rtrequest)(int, struct rtentry *, struct sockaddr *) = NULL;
int error = 0;
pvcsif = (struct pvcsif *)shadow->if_softc;
ifp = pvcsif->sif_ifp;
if (ifp == 0 || ifp->if_ioctl == 0)
return (EOPNOTSUPP);
/*
* pre process
*/
switch (cmd) {
case SIOCGPVCSIF:
snprintf(ifr->ifr_name, sizeof(ifr->ifr_name),
"%s%d", ifp->if_name, ifp->if_unit);
return (0);
case SIOCGPVCTX:
do {
struct pvctxreq *pvcreq = (struct pvctxreq *)data;
snprintf(pvcreq->pvc_ifname,
sizeof(pvcreq->pvc_ifname), "%s%d",
ifp->if_name, ifp->if_unit);
pvcreq->pvc_aph = pvcsif->sif_aph;
} while (0);
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
if (ifr == 0)
return (EAFNOSUPPORT); /* XXX */
switch (ifr->ifr_addr.sa_family) {
#ifdef INET
case AF_INET:
return (0);
#endif
#ifdef INET6
case AF_INET6:
return (0);
#endif
default:
return (EAFNOSUPPORT);
}
break;
case SIOCSIFADDR:
if (ifp->if_flags & IFF_UP) {
/* real if is already up */
shadow->if_flags = ifp->if_flags |
(IFF_POINTOPOINT|IFF_MULTICAST);
return (0);
}
/*
* XXX: save the rtrequest field since the atm driver
* overwrites this field.
*/
ifa_rtrequest = ((struct ifaddr *)data)->ifa_rtrequest;
break;
case SIOCSIFFLAGS:
if ((shadow->if_flags & IFF_UP) == 0) {
/*
* interface down. don't pass this to
* the real interface.
*/
return (0);
}
if (shadow->if_flags & IFF_UP) {
/*
* interface up. if the real if is already up,
* nothing to do.
*/
if (ifp->if_flags & IFF_UP) {
shadow->if_flags = ifp->if_flags |
(IFF_POINTOPOINT|IFF_MULTICAST);
return (0);
}
}
break;
}
/*
* pass the ioctl to the genuine interface
*/
error = (*ifp->if_ioctl)(ifp, cmd, data);
/*
* post process
*/
switch (cmd) {
case SIOCSIFMTU:
shadow->if_mtu = ifp->if_mtu;
break;
case SIOCSIFADDR:
/* restore rtrequest */
((struct ifaddr *)data)->ifa_rtrequest = ifa_rtrequest;
/* fall into... */
case SIOCSIFFLAGS:
/* update if_flags */
shadow->if_flags = ifp->if_flags
| (IFF_POINTOPOINT|IFF_MULTICAST);
break;
}
return (error);
}
int pvc_setaph(shadow, aph)
struct ifnet *shadow;
struct atm_pseudohdr *aph;
{
struct pvcsif *pvcsif;
pvcsif = shadow->if_softc;
bcopy(aph, &pvcsif->sif_aph, sizeof(struct atm_pseudohdr));
return (0);
}
#endif /* ATM_PVCEXT */