freebsd-nq/sys/net/if_ppp.c
Peter Wemm 9481c477f0 Don't dereference sc->sc_setmtu if it's NULL (such as when it's not running)
as discussed on current. (bde pointed out the cause of the problem)

Reported by: dev@fgate.flevel.co.uk
1996-07-21 17:14:06 +00:00

1444 lines
33 KiB
C

/*
* if_ppp.c - Point-to-Point Protocol (PPP) Asynchronous driver.
*
* Copyright (c) 1989 Carnegie Mellon University.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by Carnegie Mellon University. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Drew D. Perkins
* Carnegie Mellon University
* 4910 Forbes Ave.
* Pittsburgh, PA 15213
* (412) 268-8576
* ddp@andrew.cmu.edu
*
* Based on:
* @(#)if_sl.c 7.6.1.2 (Berkeley) 2/15/89
*
* Copyright (c) 1987 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Serial Line interface
*
* Rick Adams
* Center for Seismic Studies
* 1300 N 17th Street, Suite 1450
* Arlington, Virginia 22209
* (703)276-7900
* rick@seismo.ARPA
* seismo!rick
*
* Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
* Converted to 4.3BSD Beta by Chris Torek.
* Other changes made at Berkeley, based in part on code by Kirk Smith.
*
* Converted to 4.3BSD+ 386BSD by Brad Parker (brad@cayman.com)
* Added VJ tcp header compression; more unified ioctls
*
* Extensively modified by Paul Mackerras (paulus@cs.anu.edu.au).
* Cleaned up a lot of the mbuf-related code to fix bugs that
* caused system crashes and packet corruption. Changed pppstart
* so that it doesn't just give up with a collision if the whole
* packet doesn't fit in the output ring buffer.
*
* Added priority queueing for interactive IP packets, following
* the model of if_sl.c, plus hooks for bpf.
* Paul Mackerras (paulus@cs.anu.edu.au).
*/
/* $Id: if_ppp.c,v 1.35 1996/06/12 19:24:00 gpalmer Exp $ */
/* from if_ppp.c,v 1.5 1995/08/16 01:36:38 paulus Exp */
/* from if_sl.c,v 1.11 84/10/04 12:54:47 rick Exp */
#include "ppp.h"
#if NPPP > 0
#define VJC
#define PPP_COMPRESS
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#if INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#endif
#if IPX
#include <netipx/ipx.h>
#include <netipx/ipx_if.h>
#endif
#include "bpfilter.h"
#if NBPFILTER > 0
#include <sys/time.h>
#include <net/bpf.h>
#endif
#ifdef VJC
#include <net/slcompress.h>
#endif
#include <net/ppp_defs.h>
#include <net/if_ppp.h>
#include <net/if_pppvar.h>
#ifdef PPP_COMPRESS
#define PACKETPTR struct mbuf *
#include <net/ppp_comp.h>
#endif
struct ppp_softc ppp_softc[NPPP];
static void pppattach __P((void *));
PSEUDO_SET(pppattach, if_ppp);
static int pppsioctl __P((struct ifnet *ifp, int cmd, caddr_t data));
static void pppintr __P((void));
static void ppp_requeue __P((struct ppp_softc *));
static void ppp_outpkt __P((struct ppp_softc *));
static void ppp_ccp __P((struct ppp_softc *, struct mbuf *m, int rcvd));
static void ppp_ccp_closed __P((struct ppp_softc *));
static void ppp_inproc __P((struct ppp_softc *, struct mbuf *));
static void pppdumpm __P((struct mbuf *m0));
/*
* Some useful mbuf macros not in mbuf.h.
*/
#define M_IS_CLUSTER(m) ((m)->m_flags & M_EXT)
#define M_DATASTART(m) \
(M_IS_CLUSTER(m) ? (m)->m_ext.ext_buf : \
(m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat)
#define M_DATASIZE(m) \
(M_IS_CLUSTER(m) ? (m)->m_ext.ext_size : \
(m)->m_flags & M_PKTHDR ? MHLEN: MLEN)
/*
* We steal two bits in the mbuf m_flags, to mark high-priority packets
* for output, and received packets following lost/corrupted packets.
*/
#define M_HIGHPRI 0x2000 /* output packet for sc_fastq */
#define M_ERRMARK 0x4000 /* steal a bit in mbuf m_flags */
#ifdef PPP_COMPRESS
/*
* List of compressors we know about.
* We leave some space so maybe we can modload compressors.
*/
extern struct compressor ppp_bsd_compress;
static struct compressor *ppp_compressors[8] = {
#if DO_BSD_COMPRESS
&ppp_bsd_compress,
#endif
NULL
};
#endif /* PPP_COMPRESS */
/*
* Called from boot code to establish ppp interfaces.
*/
static void
pppattach(dummy)
void *dummy;
{
register struct ppp_softc *sc;
register int i = 0;
for (sc = ppp_softc; i < NPPP; sc++) {
sc->sc_if.if_name = "ppp";
sc->sc_if.if_unit = i++;
sc->sc_if.if_mtu = PPP_MTU;
sc->sc_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
sc->sc_if.if_type = IFT_PPP;
sc->sc_if.if_hdrlen = PPP_HDRLEN;
sc->sc_if.if_ioctl = pppsioctl;
sc->sc_if.if_output = pppoutput;
sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
sc->sc_inq.ifq_maxlen = IFQ_MAXLEN;
sc->sc_fastq.ifq_maxlen = IFQ_MAXLEN;
sc->sc_rawq.ifq_maxlen = IFQ_MAXLEN;
if_attach(&sc->sc_if);
#if NBPFILTER > 0
bpfattach(&sc->sc_if, DLT_PPP, PPP_HDRLEN);
#endif
}
register_netisr(NETISR_PPP, pppintr);
}
/*
* Allocate a ppp interface unit and initialize it.
*/
struct ppp_softc *
pppalloc(pid)
pid_t pid;
{
int nppp, i;
struct ppp_softc *sc;
for (nppp = 0, sc = ppp_softc; nppp < NPPP; nppp++, sc++)
if (sc->sc_xfer == pid) {
sc->sc_xfer = 0;
return sc;
}
for (nppp = 0, sc = ppp_softc; nppp < NPPP; nppp++, sc++)
if (sc->sc_devp == NULL)
break;
if (nppp >= NPPP)
return NULL;
sc->sc_flags = 0;
sc->sc_mru = PPP_MRU;
sc->sc_relinq = NULL;
#ifdef VJC
sl_compress_init(&sc->sc_comp, -1);
#endif
#ifdef PPP_COMPRESS
sc->sc_xc_state = NULL;
sc->sc_rc_state = NULL;
#endif /* PPP_COMPRESS */
for (i = 0; i < NUM_NP; ++i)
sc->sc_npmode[i] = NPMODE_ERROR;
sc->sc_npqueue = NULL;
sc->sc_npqtail = &sc->sc_npqueue;
sc->sc_last_sent = sc->sc_last_recv = time.tv_sec;
return sc;
}
/*
* Deallocate a ppp unit. Must be called at splnet or higher.
*/
void
pppdealloc(sc)
struct ppp_softc *sc;
{
struct mbuf *m;
if_down(&sc->sc_if);
sc->sc_if.if_flags &= ~(IFF_UP|IFF_RUNNING);
microtime(&sc->sc_if.if_lastchange);
sc->sc_devp = NULL;
sc->sc_xfer = 0;
for (;;) {
IF_DEQUEUE(&sc->sc_rawq, m);
if (m == NULL)
break;
m_freem(m);
}
for (;;) {
IF_DEQUEUE(&sc->sc_inq, m);
if (m == NULL)
break;
m_freem(m);
}
for (;;) {
IF_DEQUEUE(&sc->sc_fastq, m);
if (m == NULL)
break;
m_freem(m);
}
while ((m = sc->sc_npqueue) != NULL) {
sc->sc_npqueue = m->m_nextpkt;
m_freem(m);
}
if (sc->sc_togo != NULL) {
m_freem(sc->sc_togo);
sc->sc_togo = NULL;
}
#ifdef PPP_COMPRESS
ppp_ccp_closed(sc);
sc->sc_xc_state = NULL;
sc->sc_rc_state = NULL;
#endif /* PPP_COMPRESS */
}
/*
* Ioctl routine for generic ppp devices.
*/
int
pppioctl(sc, cmd, data, flag, p)
struct ppp_softc *sc;
caddr_t data;
int cmd, flag;
struct proc *p;
{
int s, error, flags, mru, nb, npx;
struct ppp_option_data *odp;
struct compressor **cp;
struct npioctl *npi;
time_t t;
#ifdef PPP_COMPRESS
u_char ccp_option[CCP_MAX_OPTION_LENGTH];
#endif
switch (cmd) {
case FIONREAD:
*(int *)data = sc->sc_inq.ifq_len;
break;
case PPPIOCGUNIT:
*(int *)data = sc->sc_if.if_unit;
break;
case PPPIOCGFLAGS:
*(u_int *)data = sc->sc_flags;
break;
case PPPIOCSFLAGS:
if (error = suser(p->p_ucred, &p->p_acflag))
return (error);
flags = *(int *)data & SC_MASK;
s = splnet();
#ifdef PPP_COMPRESS
if (sc->sc_flags & SC_CCP_OPEN && !(flags & SC_CCP_OPEN))
ppp_ccp_closed(sc);
#endif
splimp();
sc->sc_flags = (sc->sc_flags & ~SC_MASK) | flags;
splx(s);
break;
case PPPIOCSMRU:
if (error = suser(p->p_ucred, &p->p_acflag))
return (error);
mru = *(int *)data;
if (mru >= PPP_MRU && mru <= PPP_MAXMRU)
sc->sc_mru = mru;
break;
case PPPIOCGMRU:
*(int *)data = sc->sc_mru;
break;
#ifdef VJC
case PPPIOCSMAXCID:
if (error = suser(p->p_ucred, &p->p_acflag))
return (error);
s = splnet();
sl_compress_init(&sc->sc_comp, *(int *)data);
splx(s);
break;
#endif
case PPPIOCXFERUNIT:
if (error = suser(p->p_ucred, &p->p_acflag))
return (error);
sc->sc_xfer = p->p_pid;
break;
#ifdef PPP_COMPRESS
case PPPIOCSCOMPRESS:
if (error = suser(p->p_ucred, &p->p_acflag))
return (error);
odp = (struct ppp_option_data *) data;
nb = odp->length;
if (nb > sizeof(ccp_option))
nb = sizeof(ccp_option);
if (error = copyin(odp->ptr, ccp_option, nb))
return (error);
if (ccp_option[1] < 2) /* preliminary check on the length byte */
return (EINVAL);
for (cp = ppp_compressors; *cp != NULL; ++cp)
if ((*cp)->compress_proto == ccp_option[0]) {
/*
* Found a handler for the protocol - try to allocate
* a compressor or decompressor.
*/
error = 0;
if (odp->transmit) {
s = splnet();
if (sc->sc_xc_state != NULL)
(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
sc->sc_xcomp = *cp;
sc->sc_xc_state = (*cp)->comp_alloc(ccp_option, nb);
if (sc->sc_xc_state == NULL) {
if (sc->sc_flags & SC_DEBUG)
printf("ppp%d: comp_alloc failed\n",
sc->sc_if.if_unit);
error = ENOBUFS;
}
splimp();
sc->sc_flags &= ~SC_COMP_RUN;
splx(s);
} else {
s = splnet();
if (sc->sc_rc_state != NULL)
(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
sc->sc_rcomp = *cp;
sc->sc_rc_state = (*cp)->decomp_alloc(ccp_option, nb);
if (sc->sc_rc_state == NULL) {
if (sc->sc_flags & SC_DEBUG)
printf("ppp%d: decomp_alloc failed\n",
sc->sc_if.if_unit);
error = ENOBUFS;
}
splimp();
sc->sc_flags &= ~SC_DECOMP_RUN;
splx(s);
}
return (error);
}
if (sc->sc_flags & SC_DEBUG)
printf("ppp%d: no compressor for [%x %x %x], %x\n",
sc->sc_if.if_unit, ccp_option[0], ccp_option[1],
ccp_option[2], nb);
return (EINVAL); /* no handler found */
#endif /* PPP_COMPRESS */
case PPPIOCGNPMODE:
case PPPIOCSNPMODE:
npi = (struct npioctl *) data;
switch (npi->protocol) {
case PPP_IP:
npx = NP_IP;
break;
default:
return EINVAL;
}
if (cmd == PPPIOCGNPMODE) {
npi->mode = sc->sc_npmode[npx];
} else {
if (error = suser(p->p_ucred, &p->p_acflag))
return (error);
if (npi->mode != sc->sc_npmode[npx]) {
s = splnet();
sc->sc_npmode[npx] = npi->mode;
if (npi->mode != NPMODE_QUEUE) {
ppp_requeue(sc);
(*sc->sc_start)(sc);
}
splx(s);
}
}
break;
case PPPIOCGIDLE:
s = splnet();
t = time.tv_sec;
((struct ppp_idle *)data)->xmit_idle = t - sc->sc_last_sent;
((struct ppp_idle *)data)->recv_idle = t - sc->sc_last_recv;
splx(s);
break;
default:
return (-1);
}
return (0);
}
/*
* Process an ioctl request to the ppp network interface.
*/
static int
pppsioctl(ifp, cmd, data)
register struct ifnet *ifp;
int cmd;
caddr_t data;
{
struct proc *p = curproc; /* XXX */
register struct ppp_softc *sc = &ppp_softc[ifp->if_unit];
register struct ifaddr *ifa = (struct ifaddr *)data;
register struct ifreq *ifr = (struct ifreq *)data;
struct ppp_stats *psp;
#ifdef PPP_COMPRESS
struct ppp_comp_stats *pcp;
#endif
int s = splimp(), error = 0;
switch (cmd) {
case SIOCSIFFLAGS:
if ((ifp->if_flags & IFF_RUNNING) == 0)
ifp->if_flags &= ~IFF_UP;
break;
case SIOCSIFADDR:
case SIOCAIFADDR:
switch(ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef IPX
case AF_IPX:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCSIFDSTADDR:
switch(ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef IPX
case AF_IPX:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCSIFMTU:
if (error = suser(p->p_ucred, &p->p_acflag))
break;
if (ifr->ifr_mtu > PPP_MAXMTU)
error = EINVAL;
else {
sc->sc_if.if_mtu = ifr->ifr_mtu;
if (sc->sc_setmtu)
(*sc->sc_setmtu)(sc);
}
break;
case SIOCGIFMTU:
ifr->ifr_mtu = sc->sc_if.if_mtu;
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
switch(ifr->ifr_addr.sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef IPX /* ??? IPX support multicast? */
case AF_IPX:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCGPPPSTATS:
psp = &((struct ifpppstatsreq *) data)->stats;
bzero(psp, sizeof(*psp));
psp->p.ppp_ibytes = sc->sc_bytesrcvd;
psp->p.ppp_ipackets = ifp->if_ipackets;
psp->p.ppp_ierrors = ifp->if_ierrors;
psp->p.ppp_obytes = sc->sc_bytessent;
psp->p.ppp_opackets = ifp->if_opackets;
psp->p.ppp_oerrors = ifp->if_oerrors;
#ifdef VJC
psp->vj.vjs_packets = sc->sc_comp.sls_packets;
psp->vj.vjs_compressed = sc->sc_comp.sls_compressed;
psp->vj.vjs_searches = sc->sc_comp.sls_searches;
psp->vj.vjs_misses = sc->sc_comp.sls_misses;
psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin;
psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin;
psp->vj.vjs_errorin = sc->sc_comp.sls_errorin;
psp->vj.vjs_tossed = sc->sc_comp.sls_tossed;
#endif /* VJC */
break;
#ifdef PPP_COMPRESS
case SIOCGPPPCSTATS:
pcp = &((struct ifpppcstatsreq *) data)->stats;
bzero(pcp, sizeof(*pcp));
if (sc->sc_xc_state != NULL)
(*sc->sc_xcomp->comp_stat)(sc->sc_xc_state, &pcp->c);
if (sc->sc_rc_state != NULL)
(*sc->sc_rcomp->decomp_stat)(sc->sc_rc_state, &pcp->d);
break;
#endif /* PPP_COMPRESS */
default:
error = ENOTTY;
}
splx(s);
return (error);
}
/*
* Queue a packet. Start transmission if not active.
* Packet is placed in Information field of PPP frame.
* Called at splnet as the if->if_output handler.
* Called at splnet from pppwrite().
*/
int
pppoutput(ifp, m0, dst, rtp)
struct ifnet *ifp;
struct mbuf *m0;
struct sockaddr *dst;
struct rtentry *rtp;
{
register struct ppp_softc *sc = &ppp_softc[ifp->if_unit];
int protocol, address, control;
u_char *cp;
int s, error;
struct ip *ip;
struct ifqueue *ifq;
enum NPmode mode;
if (sc->sc_devp == NULL || (ifp->if_flags & IFF_RUNNING) == 0
|| (ifp->if_flags & IFF_UP) == 0 && dst->sa_family != AF_UNSPEC) {
error = ENETDOWN; /* sort of */
goto bad;
}
/*
* Compute PPP header.
*/
m0->m_flags &= ~M_HIGHPRI;
switch (dst->sa_family) {
#ifdef INET
case AF_INET:
address = PPP_ALLSTATIONS;
control = PPP_UI;
protocol = PPP_IP;
mode = sc->sc_npmode[NP_IP];
/*
* If this packet has the "low delay" bit set in the IP header,
* put it on the fastq instead.
*/
ip = mtod(m0, struct ip *);
if (ip->ip_tos & IPTOS_LOWDELAY)
m0->m_flags |= M_HIGHPRI;
break;
#endif
#ifdef IPX
case AF_IPX:
/*
* This is pretty bogus.. We dont have an ipxcp module in pppd
* yet to configure the link parameters. Sigh. I guess a
* manual ifconfig would do.... -Peter
*/
address = PPP_ALLSTATIONS;
control = PPP_UI;
protocol = PPP_IPX;
mode = NPMODE_PASS;
break;
#endif
case AF_UNSPEC:
address = PPP_ADDRESS(dst->sa_data);
control = PPP_CONTROL(dst->sa_data);
protocol = PPP_PROTOCOL(dst->sa_data);
mode = NPMODE_PASS;
break;
default:
printf("ppp%d: af%d not supported\n", ifp->if_unit, dst->sa_family);
error = EAFNOSUPPORT;
goto bad;
}
/*
* Drop this packet, or return an error, if necessary.
*/
if (mode == NPMODE_ERROR) {
error = ENETDOWN;
goto bad;
}
if (mode == NPMODE_DROP) {
error = 0;
goto bad;
}
/*
* Add PPP header. If no space in first mbuf, allocate another.
* (This assumes M_LEADINGSPACE is always 0 for a cluster mbuf.)
*/
if (M_LEADINGSPACE(m0) < PPP_HDRLEN) {
m0 = m_prepend(m0, PPP_HDRLEN, M_DONTWAIT);
if (m0 == 0) {
error = ENOBUFS;
goto bad;
}
m0->m_len = 0;
} else
m0->m_data -= PPP_HDRLEN;
cp = mtod(m0, u_char *);
*cp++ = address;
*cp++ = control;
*cp++ = protocol >> 8;
*cp++ = protocol & 0xff;
m0->m_len += PPP_HDRLEN;
if (sc->sc_flags & SC_LOG_OUTPKT) {
printf("ppp%d output: ", ifp->if_unit);
pppdumpm(m0);
}
#if NBPFILTER > 0
/*
* See if bpf wants to look at the packet.
*/
if (ifp->if_bpf)
bpf_mtap(ifp, m0);
#endif
/*
* Put the packet on the appropriate queue.
*/
s = splnet(); /* redundant */
if (mode == NPMODE_QUEUE) {
/* XXX we should limit the number of packets on this queue */
*sc->sc_npqtail = m0;
m0->m_nextpkt = NULL;
sc->sc_npqtail = &m0->m_nextpkt;
} else {
/* fastq and if_snd are emptied at splnet now */
ifq = (m0->m_flags & M_HIGHPRI)? &sc->sc_fastq: &ifp->if_snd;
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
splx(s);
sc->sc_if.if_oerrors++;
error = ENOBUFS;
goto bad;
}
IF_ENQUEUE(ifq, m0);
(*sc->sc_start)(sc);
}
splx(s);
return (0);
bad:
m_freem(m0);
return (error);
}
/*
* After a change in the NPmode for some NP, move packets from the
* npqueue to the send queue or the fast queue as appropriate.
* Should be called at splnet.
*/
static void
ppp_requeue(sc)
struct ppp_softc *sc;
{
struct mbuf *m, **mpp;
struct ifqueue *ifq;
enum NPmode mode;
for (mpp = &sc->sc_npqueue; (m = *mpp) != NULL; ) {
switch (PPP_PROTOCOL(mtod(m, u_char *))) {
case PPP_IP:
mode = sc->sc_npmode[NP_IP];
break;
default:
mode = NPMODE_PASS;
}
switch (mode) {
case NPMODE_PASS:
/*
* This packet can now go on one of the queues to be sent.
*/
*mpp = m->m_nextpkt;
m->m_nextpkt = NULL;
ifq = (m->m_flags & M_HIGHPRI)? &sc->sc_fastq: &sc->sc_if.if_snd;
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
sc->sc_if.if_oerrors++;
} else
IF_ENQUEUE(ifq, m);
break;
case NPMODE_DROP:
case NPMODE_ERROR:
*mpp = m->m_nextpkt;
m_freem(m);
break;
case NPMODE_QUEUE:
mpp = &m->m_nextpkt;
break;
}
}
sc->sc_npqtail = mpp;
}
/*
* Get a packet to send. This procedure is intended to be called
* at spltty()/splimp(), so it takes little time. If there isn't
* a packet waiting to go out, it schedules a software interrupt
* to prepare a new packet; the device start routine gets called
* again when a packet is ready.
*/
struct mbuf *
ppp_dequeue(sc)
struct ppp_softc *sc;
{
struct mbuf *m;
int s = splimp();
m = sc->sc_togo;
if (m) {
/*
* Had a packet waiting - send it.
*/
sc->sc_togo = NULL;
sc->sc_flags |= SC_TBUSY;
splx(s);
return m;
}
/*
* Remember we wanted a packet and schedule a software interrupt.
*/
sc->sc_flags &= ~SC_TBUSY;
schednetisr(NETISR_PPP);
splx(s);
return NULL;
}
/*
* Software interrupt routine, called at splnet.
*/
static void
pppintr()
{
struct ppp_softc *sc;
int i, s;
struct mbuf *m;
sc = ppp_softc;
for (i = 0; i < NPPP; ++i, ++sc) {
s = splimp();
if (!(sc->sc_flags & SC_TBUSY) && sc->sc_togo == NULL
&& (sc->sc_if.if_snd.ifq_head || sc->sc_fastq.ifq_head)) {
splx(s);
ppp_outpkt(sc);
} else
splx(s);
for (;;) {
s = splimp();
IF_DEQUEUE(&sc->sc_rawq, m);
splx(s);
if (m == NULL)
break;
ppp_inproc(sc, m);
}
}
}
/*
* Grab another packet off a queue and apply VJ compression,
* packet compression, address/control and/or protocol compression
* if enabled. Should be called at splnet.
*/
static void
ppp_outpkt(sc)
struct ppp_softc *sc;
{
struct mbuf *m, *mp;
u_char *cp;
int address, control, protocol;
/*
* Grab a packet to send: first try the fast queue, then the
* normal queue.
*/
IF_DEQUEUE(&sc->sc_fastq, m);
if (m == NULL)
IF_DEQUEUE(&sc->sc_if.if_snd, m);
if (m == NULL)
return;
/*
* Extract the ppp header of the new packet.
* The ppp header will be in one mbuf.
*/
cp = mtod(m, u_char *);
address = PPP_ADDRESS(cp);
control = PPP_CONTROL(cp);
protocol = PPP_PROTOCOL(cp);
switch (protocol) {
case PPP_IP:
/*
* Update the time we sent the most recent packet.
*/
sc->sc_last_sent = time.tv_sec;
#ifdef VJC
/*
* If the packet is a TCP/IP packet, see if we can compress it.
*/
if (sc->sc_flags & SC_COMP_TCP) {
struct ip *ip;
int type;
mp = m;
ip = (struct ip *) (cp + PPP_HDRLEN);
if (mp->m_len <= PPP_HDRLEN) {
mp = mp->m_next;
if (mp == NULL)
break;
ip = mtod(mp, struct ip *);
}
/* this code assumes the IP/TCP header is in one non-shared mbuf */
if (ip->ip_p == IPPROTO_TCP) {
type = sl_compress_tcp(mp, ip, &sc->sc_comp,
!(sc->sc_flags & SC_NO_TCP_CCID));
switch (type) {
case TYPE_UNCOMPRESSED_TCP:
protocol = PPP_VJC_UNCOMP;
break;
case TYPE_COMPRESSED_TCP:
protocol = PPP_VJC_COMP;
cp = mtod(m, u_char *);
cp[0] = address; /* header has moved */
cp[1] = control;
cp[2] = 0;
break;
}
cp[3] = protocol; /* update protocol in PPP header */
}
}
#endif /* VJC */
break;
#ifdef PPP_COMPRESS
case PPP_CCP:
ppp_ccp(sc, m, 0);
break;
#endif /* PPP_COMPRESS */
}
#ifdef PPP_COMPRESS
if (protocol != PPP_LCP && protocol != PPP_CCP
&& sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN)) {
struct mbuf *mcomp = NULL;
int slen, clen;
slen = 0;
for (mp = m; mp != NULL; mp = mp->m_next)
slen += mp->m_len;
clen = (*sc->sc_xcomp->compress)
(sc->sc_xc_state, &mcomp, m, slen,
(sc->sc_flags & SC_CCP_UP? sc->sc_if.if_mtu: 0));
if (mcomp != NULL) {
m_freem(m);
m = mcomp;
cp = mtod(m, u_char *);
protocol = cp[3];
}
}
#endif /* PPP_COMPRESS */
/*
* Compress the address/control and protocol, if possible.
*/
if (sc->sc_flags & SC_COMP_AC && address == PPP_ALLSTATIONS &&
control == PPP_UI && protocol != PPP_ALLSTATIONS &&
protocol != PPP_LCP) {
/* can compress address/control */
m->m_data += 2;
m->m_len -= 2;
}
if (sc->sc_flags & SC_COMP_PROT && protocol < 0xFF) {
/* can compress protocol */
if (mtod(m, u_char *) == cp) {
cp[2] = cp[1]; /* move address/control up */
cp[1] = cp[0];
}
++m->m_data;
--m->m_len;
}
/*
* potential race here. We could write to sc_togo at softnet priority.
* the tty system could interrupt and steal the sc_togo before sc_start
* is called. Either way, it's sent... No big deal.. :-)
*/
sc->sc_togo = m;
(*sc->sc_start)(sc);
}
#ifdef PPP_COMPRESS
/*
* Handle a CCP packet. `rcvd' is 1 if the packet was received,
* 0 if it is about to be transmitted.
*/
static void
ppp_ccp(sc, m, rcvd)
struct ppp_softc *sc;
struct mbuf *m;
int rcvd;
{
u_char *dp, *ep;
struct mbuf *mp;
int slen, s;
/*
* Get a pointer to the data after the PPP header.
*/
if (m->m_len <= PPP_HDRLEN) {
mp = m->m_next;
if (mp == NULL)
return;
dp = (mp != NULL)? mtod(mp, u_char *): NULL;
} else {
mp = m;
dp = mtod(mp, u_char *) + PPP_HDRLEN;
}
ep = mtod(mp, u_char *) + mp->m_len;
if (dp + CCP_HDRLEN > ep)
return;
slen = CCP_LENGTH(dp);
if (dp + slen > ep) {
if (sc->sc_flags & SC_DEBUG)
printf("if_ppp/ccp: not enough data in mbuf (%x+%x > %x+%x)\n",
dp, slen, mtod(mp, u_char *), mp->m_len);
return;
}
switch (CCP_CODE(dp)) {
case CCP_CONFREQ:
case CCP_TERMREQ:
case CCP_TERMACK:
/* CCP must be going down - disable compression */
if (sc->sc_flags & SC_CCP_UP) {
s = splimp();
sc->sc_flags &= ~(SC_CCP_UP | SC_COMP_RUN | SC_DECOMP_RUN);
splx(s);
}
break;
case CCP_CONFACK:
if (sc->sc_flags & SC_CCP_OPEN && !(sc->sc_flags & SC_CCP_UP)
&& slen >= CCP_HDRLEN + CCP_OPT_MINLEN
&& slen >= CCP_OPT_LENGTH(dp + CCP_HDRLEN) + CCP_HDRLEN) {
if (!rcvd) {
/* we're agreeing to send compressed packets. */
if (sc->sc_xc_state != NULL
&& (*sc->sc_xcomp->comp_init)
(sc->sc_xc_state, dp + CCP_HDRLEN, slen - CCP_HDRLEN,
sc->sc_if.if_unit, 0, sc->sc_flags & SC_DEBUG)) {
s = splimp();
sc->sc_flags |= SC_COMP_RUN;
splx(s);
}
} else {
/* peer is agreeing to send compressed packets. */
if (sc->sc_rc_state != NULL
&& (*sc->sc_rcomp->decomp_init)
(sc->sc_rc_state, dp + CCP_HDRLEN, slen - CCP_HDRLEN,
sc->sc_if.if_unit, 0, sc->sc_mru,
sc->sc_flags & SC_DEBUG)) {
s = splimp();
sc->sc_flags |= SC_DECOMP_RUN;
sc->sc_flags &= ~(SC_DC_ERROR | SC_DC_FERROR);
splx(s);
}
}
}
break;
case CCP_RESETACK:
if (sc->sc_flags & SC_CCP_UP) {
if (!rcvd) {
if (sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN))
(*sc->sc_xcomp->comp_reset)(sc->sc_xc_state);
} else {
if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
(*sc->sc_rcomp->decomp_reset)(sc->sc_rc_state);
s = splimp();
sc->sc_flags &= ~SC_DC_ERROR;
splx(s);
}
}
}
break;
}
}
/*
* CCP is down; free (de)compressor state if necessary.
*/
static void
ppp_ccp_closed(sc)
struct ppp_softc *sc;
{
if (sc->sc_xc_state) {
(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
sc->sc_xc_state = NULL;
}
if (sc->sc_rc_state) {
(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
sc->sc_rc_state = NULL;
}
}
#endif /* PPP_COMPRESS */
/*
* PPP packet input routine.
* The caller has checked and removed the FCS and has inserted
* the address/control bytes and the protocol high byte if they
* were omitted.
*/
void
ppppktin(sc, m, lost)
struct ppp_softc *sc;
struct mbuf *m;
int lost;
{
int s = splimp();
if (lost)
m->m_flags |= M_ERRMARK;
IF_ENQUEUE(&sc->sc_rawq, m);
schednetisr(NETISR_PPP);
splx(s);
}
/*
* Process a received PPP packet, doing decompression as necessary.
*/
#define COMPTYPE(proto) ((proto) == PPP_VJC_COMP? TYPE_COMPRESSED_TCP: \
TYPE_UNCOMPRESSED_TCP)
static void
ppp_inproc(sc, m)
struct ppp_softc *sc;
struct mbuf *m;
{
struct ifqueue *inq;
int s, ilen = 0, xlen, proto, rv;
u_char *cp, adrs, ctrl;
struct mbuf *mp, *dmp = NULL;
u_char *iphdr;
u_int hlen;
sc->sc_if.if_ipackets++;
if (sc->sc_flags & SC_LOG_INPKT) {
printf("ppp%d: got %d bytes\n", sc->sc_if.if_unit, ilen);
pppdumpm(m);
}
cp = mtod(m, u_char *);
adrs = PPP_ADDRESS(cp);
ctrl = PPP_CONTROL(cp);
proto = PPP_PROTOCOL(cp);
if (m->m_flags & M_ERRMARK) {
m->m_flags &= ~M_ERRMARK;
s = splimp();
sc->sc_flags |= SC_VJ_RESET;
splx(s);
}
#ifdef PPP_COMPRESS
/*
* Decompress this packet if necessary, update the receiver's
* dictionary, or take appropriate action on a CCP packet.
*/
if (proto == PPP_COMP && sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)
&& !(sc->sc_flags & SC_DC_ERROR) && !(sc->sc_flags & SC_DC_FERROR)) {
/* decompress this packet */
rv = (*sc->sc_rcomp->decompress)(sc->sc_rc_state, m, &dmp);
if (rv == DECOMP_OK) {
m_freem(m);
if (dmp == NULL) {
/* no error, but no decompressed packet produced */
return;
}
m = dmp;
cp = mtod(m, u_char *);
proto = PPP_PROTOCOL(cp);
} else {
/*
* An error has occurred in decompression.
* Pass the compressed packet up to pppd, which may take
* CCP down or issue a Reset-Req.
*/
if (sc->sc_flags & SC_DEBUG)
printf("ppp%d: decompress failed %d\n", sc->sc_if.if_unit, rv);
s = splimp();
sc->sc_flags |= SC_VJ_RESET;
if (rv == DECOMP_ERROR)
sc->sc_flags |= SC_DC_ERROR;
else
sc->sc_flags |= SC_DC_FERROR;
splx(s);
}
} else {
if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
(*sc->sc_rcomp->incomp)(sc->sc_rc_state, m);
}
if (proto == PPP_CCP) {
ppp_ccp(sc, m, 1);
}
}
#endif
ilen = 0;
for (mp = m; mp != NULL; mp = mp->m_next)
ilen += mp->m_len;
#ifdef VJC
if (sc->sc_flags & SC_VJ_RESET) {
/*
* If we've missed a packet, we must toss subsequent compressed
* packets which don't have an explicit connection ID.
*/
sl_uncompress_tcp(NULL, 0, TYPE_ERROR, &sc->sc_comp);
s = splimp();
sc->sc_flags &= ~SC_VJ_RESET;
splx(s);
}
/*
* See if we have a VJ-compressed packet to uncompress.
*/
if (proto == PPP_VJC_COMP) {
if (sc->sc_flags & SC_REJ_COMP_TCP)
goto bad;
xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN, m->m_len - PPP_HDRLEN,
ilen - PPP_HDRLEN, TYPE_COMPRESSED_TCP,
&sc->sc_comp, &iphdr, &hlen);
if (xlen <= 0) {
if (sc->sc_flags & SC_DEBUG)
printf("ppp%d: VJ uncompress failed on type comp\n",
sc->sc_if.if_unit);
goto bad;
}
/* Copy the PPP and IP headers into a new mbuf. */
MGETHDR(mp, M_DONTWAIT, MT_DATA);
if (mp == NULL)
goto bad;
mp->m_len = 0;
mp->m_next = NULL;
if (hlen + PPP_HDRLEN > MHLEN) {
MCLGET(mp, M_DONTWAIT);
if (M_TRAILINGSPACE(mp) < hlen + PPP_HDRLEN) {
m_freem(mp);
goto bad; /* lose if big headers and no clusters */
}
}
cp = mtod(mp, u_char *);
cp[0] = adrs;
cp[1] = ctrl;
cp[2] = 0;
cp[3] = PPP_IP;
proto = PPP_IP;
bcopy(iphdr, cp + PPP_HDRLEN, hlen);
mp->m_len = hlen + PPP_HDRLEN;
/*
* Trim the PPP and VJ headers off the old mbuf
* and stick the new and old mbufs together.
*/
m->m_data += PPP_HDRLEN + xlen;
m->m_len -= PPP_HDRLEN + xlen;
if (m->m_len <= M_TRAILINGSPACE(mp)) {
bcopy(mtod(m, u_char *), mtod(mp, u_char *) + mp->m_len, m->m_len);
mp->m_len += m->m_len;
MFREE(m, mp->m_next);
} else
mp->m_next = m;
m = mp;
ilen += hlen - xlen;
} else if (proto == PPP_VJC_UNCOMP) {
if (sc->sc_flags & SC_REJ_COMP_TCP)
goto bad;
xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN, m->m_len - PPP_HDRLEN,
ilen - PPP_HDRLEN, TYPE_UNCOMPRESSED_TCP,
&sc->sc_comp, &iphdr, &hlen);
if (xlen < 0) {
if (sc->sc_flags & SC_DEBUG)
printf("ppp%d: VJ uncompress failed on type uncomp\n",
sc->sc_if.if_unit);
goto bad;
}
proto = PPP_IP;
cp[3] = PPP_IP;
}
#endif /* VJC */
/*
* If the packet will fit in a header mbuf, don't waste a
* whole cluster on it.
*/
if (ilen <= MHLEN && M_IS_CLUSTER(m)) {
MGETHDR(mp, M_DONTWAIT, MT_DATA);
if (mp != NULL) {
m_copydata(m, 0, ilen, mtod(mp, caddr_t));
m_freem(m);
m = mp;
m->m_len = ilen;
}
}
m->m_pkthdr.len = ilen;
m->m_pkthdr.rcvif = &sc->sc_if;
#if NBPFILTER > 0
/* See if bpf wants to look at the packet. */
if (sc->sc_if.if_bpf)
bpf_mtap(&sc->sc_if, m);
#endif
rv = 0;
switch (proto) {
#ifdef INET
case PPP_IP:
/*
* IP packet - take off the ppp header and pass it up to IP.
*/
if ((sc->sc_if.if_flags & IFF_UP) == 0
|| sc->sc_npmode[NP_IP] != NPMODE_PASS) {
/* interface is down - drop the packet. */
m_freem(m);
return;
}
m->m_pkthdr.len -= PPP_HDRLEN;
m->m_data += PPP_HDRLEN;
m->m_len -= PPP_HDRLEN;
schednetisr(NETISR_IP);
inq = &ipintrq;
sc->sc_last_recv = time.tv_sec; /* update time of last pkt rcvd */
break;
#endif
#ifdef IPX
case PPP_IPX:
/*
* IPX packet - take off the ppp header and pass it up to IPX.
*/
if ((sc->sc_if.if_flags & IFF_UP) == 0
/* XXX: || sc->sc_npmode[NP_IPX] != NPMODE_PASS*/) {
/* interface is down - drop the packet. */
m_freem(m);
return;
}
m->m_pkthdr.len -= PPP_HDRLEN;
m->m_data += PPP_HDRLEN;
m->m_len -= PPP_HDRLEN;
schednetisr(NETISR_IPX);
inq = &ipxintrq;
sc->sc_last_recv = time.tv_sec; /* update time of last pkt rcvd */
break;
#endif
default:
/*
* Some other protocol - place on input queue for read().
*/
inq = &sc->sc_inq;
rv = 1;
break;
}
/*
* Put the packet on the appropriate input queue.
*/
s = splimp();
if (IF_QFULL(inq)) {
IF_DROP(inq);
splx(s);
if (sc->sc_flags & SC_DEBUG)
printf("ppp%d: input queue full\n", sc->sc_if.if_unit);
sc->sc_if.if_iqdrops++;
goto bad;
}
IF_ENQUEUE(inq, m);
splx(s);
if (rv)
(*sc->sc_ctlp)(sc);
return;
bad:
m_freem(m);
sc->sc_if.if_ierrors++;
}
#define MAX_DUMP_BYTES 128
static void
pppdumpm(m0)
struct mbuf *m0;
{
char buf[3*MAX_DUMP_BYTES+4];
char *bp = buf;
struct mbuf *m;
for (m = m0; m; m = m->m_next) {
int l = m->m_len;
u_char *rptr = (u_char *)m->m_data;
while (l--) {
if (bp > buf + sizeof(buf) - 4)
goto done;
*bp++ = hex2ascii(*rptr >> 4);
*bp++ = hex2ascii(*rptr++ & 0xf);
}
if (m->m_next) {
if (bp > buf + sizeof(buf) - 3)
goto done;
*bp++ = '|';
} else
*bp++ = ' ';
}
done:
if (m)
*bp++ = '>';
*bp = 0;
printf("%s\n", buf);
}
#endif /* NPPP > 0 */