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/* $NetBSD: if_ppp.c,v 1.173 2024/07/05 04:31:53 rin Exp $ */
/* Id: if_ppp.c,v 1.6 1997/03/04 03:33:00 paulus Exp */

/*
* if_ppp.c - Point-to-Point Protocol (PPP) Asynchronous driver.
*
* Copyright (c) 1984-2000 Carnegie Mellon 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. The name "Carnegie Mellon University" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For permission or any legal
* details, please contact
* Office of Technology Transfer
* Carnegie Mellon University
* 5000 Forbes Avenue
* Pittsburgh, PA 15213-3890
* (412) 268-4387, fax: (412) 268-7395
* [email protected]
*
* 4. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by Computing Services
* at Carnegie Mellon University (http://www.cmu.edu/computing/)."
*
* CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* 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
* [email protected]
* seismo!rick
*
* Pounded on heavily by Chris Torek ([email protected], 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 ([email protected])
* Added VJ tcp header compression; more unified ioctls
*
* Extensively modified by Paul Mackerras ([email protected]).
* 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 ([email protected]).
*/

/* from if_sl.c,v 1.11 84/10/04 12:54:47 rick Exp */
/* from NetBSD: if_ppp.c,v 1.15.2.2 1994/07/28 05:17:58 cgd Exp */

/*
* XXX IMP ME HARDER
*
* This is an explanation of that comment. This code used to use
* splimp() to block both network and tty interrupts. However,
* that call is deprecated. So, we have replaced the uses of
* splimp() with splhigh() in order to applomplish what it needs
* to accomplish, and added that happy little comment.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_ppp.c,v 1.173 2024/07/05 04:31:53 rin Exp $");

#ifdef _KERNEL_OPT
#include "ppp.h"
#include "opt_inet.h"
#include "opt_gateway.h"
#include "opt_ppp.h"
#endif

#ifdef INET
#define VJC
#endif
#define PPP_COMPRESS

#include <sys/param.h>
#include <sys/proc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/once.h>
#include <sys/conf.h>
#include <sys/kauth.h>
#include <sys/intr.h>
#include <sys/socketvar.h>
#include <sys/device.h>
#include <sys/module.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#ifdef INET
#include <netinet/ip.h>
#endif

#include <net/bpf.h>
#include <net/slip.h>

#ifdef VJC
#include <net/slcompress.h>
#endif

#include <net/ppp_defs.h>
#include <net/if_ppp.h>
#include <net/if_pppvar.h>
#include <sys/cpu.h>

#ifdef PPP_COMPRESS
#define PACKETPTR struct mbuf *
#include <net/ppp-comp.h>
#endif

#include "ioconf.h"

static int pppsioctl(struct ifnet *, u_long, void *);
static void ppp_requeue(struct ppp_softc *);
static void ppp_ccp(struct ppp_softc *, struct mbuf *m, int rcvd);
static void ppp_ccp_closed(struct ppp_softc *);
static void ppp_inproc(struct ppp_softc *, struct mbuf *);
static void pppdumpm(struct mbuf *m0);
#ifdef ALTQ
static void ppp_ifstart(struct ifnet *ifp);
#endif

static void pppintr(void *);

extern struct linesw ppp_disc;

/*
* We define two link layer specific mbuf flags, to mark high-priority
* packets for output, and received packets following lost/corrupted
* packets.
*/
#define M_HIGHPRI M_LINK0 /* output packet for sc_fastq */
#define M_ERRMARK M_LINK1 /* rx packet following lost/corrupted pkt */

static int ppp_clone_create(struct if_clone *, int);
static int ppp_clone_destroy(struct ifnet *);

static struct ppp_softc *ppp_create(const char *, int);

static struct {
LIST_HEAD(ppp_sclist, ppp_softc) list;
kmutex_t lock;
} ppp_softcs __cacheline_aligned;

struct if_clone ppp_cloner =
IF_CLONE_INITIALIZER("ppp", ppp_clone_create, ppp_clone_destroy);

#ifdef PPP_COMPRESS
static LIST_HEAD(, compressor) ppp_compressors = { NULL };
static kmutex_t ppp_compressors_mtx;

static int ppp_compressor_init(void);
static int ppp_compressor_destroy(void);
static struct compressor *ppp_get_compressor(uint8_t);
static void ppp_compressor_rele(struct compressor *);
#endif /* PPP_COMPRESS */

/*
* Called from boot code to establish ppp interfaces.
*/
void
pppattach(int n __unused)
{

/*
* Nothing to do here, initialization is handled by the
* module initialization code in pppinit() below).
*/
}

static void
pppinit(void)
{
/* Init the compressor sub-sub-system */
ppp_compressor_init();

if (ttyldisc_attach(&ppp_disc) != 0)
panic("%s", __func__);

mutex_init(&ppp_softcs.lock, MUTEX_DEFAULT, IPL_NONE);
LIST_INIT(&ppp_softcs.list);
if_clone_attach(&ppp_cloner);
}

static int
pppdetach(void)
{
int error = 0;

if (!LIST_EMPTY(&ppp_softcs.list))
error = EBUSY;

if (error == 0)
error = ttyldisc_detach(&ppp_disc);

if (error == 0) {
mutex_destroy(&ppp_softcs.lock);
if_clone_detach(&ppp_cloner);
ppp_compressor_destroy();
}

return error;
}

static struct ppp_softc *
ppp_create(const char *name, int unit)
{
struct ppp_softc *sc, *sci, *scl = NULL;

sc = malloc(sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO);

mutex_enter(&ppp_softcs.lock);
if (unit == -1) {
int i = 0;
LIST_FOREACH(sci, &ppp_softcs.list, sc_iflist) {
scl = sci;
if (i < sci->sc_unit) {
unit = i;
break;
} else {
#ifdef DIAGNOSTIC
KASSERT(i == sci->sc_unit);
#endif
i++;
}
}
if (unit == -1)
unit = i;
} else {
LIST_FOREACH(sci, &ppp_softcs.list, sc_iflist) {
scl = sci;
if (unit < sci->sc_unit)
break;
else if (unit == sci->sc_unit) {
free(sc, M_DEVBUF);
mutex_exit(&ppp_softcs.lock);
return NULL;
}
}
}

if (sci != NULL)
LIST_INSERT_BEFORE(sci, sc, sc_iflist);
else if (scl != NULL)
LIST_INSERT_AFTER(scl, sc, sc_iflist);
else
LIST_INSERT_HEAD(&ppp_softcs.list, sc, sc_iflist);

mutex_exit(&ppp_softcs.lock);

if_initname(&sc->sc_if, name, sc->sc_unit = unit);
callout_init(&sc->sc_timo_ch, 0);
sc->sc_if.if_softc = sc;
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_dlt = DLT_NULL;
sc->sc_if.if_ioctl = pppsioctl;
sc->sc_if.if_output = pppoutput;
#ifdef ALTQ
sc->sc_if.if_start = ppp_ifstart;
#endif
IFQ_SET_MAXLEN(&sc->sc_if.if_snd, IFQ_MAXLEN);
IFQ_SET_MAXLEN(&sc->sc_inq, IFQ_MAXLEN);
IFQ_SET_MAXLEN(&sc->sc_fastq, IFQ_MAXLEN);
IFQ_SET_MAXLEN(&sc->sc_rawq, IFQ_MAXLEN);

IFQ_LOCK_INIT(&sc->sc_fastq);

/* Ratio of 1:2 packets between the regular and the fast queue */
sc->sc_maxfastq = 2;
IFQ_SET_READY(&sc->sc_if.if_snd);
if_attach(&sc->sc_if);
if_alloc_sadl(&sc->sc_if);
bpf_attach(&sc->sc_if, DLT_NULL, 0);
return sc;
}

static int
ppp_clone_create(struct if_clone *ifc, int unit)
{
return ppp_create(ifc->ifc_name, unit) == NULL ? EEXIST : 0;
}

static int
ppp_clone_destroy(struct ifnet *ifp)
{
struct ppp_softc *sc = (struct ppp_softc *)ifp->if_softc;

if (sc->sc_devp != NULL)
return EBUSY; /* Not removing it */

mutex_enter(&ppp_softcs.lock);
LIST_REMOVE(sc, sc_iflist);
mutex_exit(&ppp_softcs.lock);

bpf_detach(ifp);
if_detach(ifp);

IFQ_LOCK_DESTROY(&sc->sc_fastq);

free(sc, M_DEVBUF);
return 0;
}

/*
* Allocate a ppp interface unit and initialize it.
*/
struct ppp_softc *
pppalloc(pid_t pid)
{
struct ppp_softc *sc = NULL, *scf;
int i;

mutex_enter(&ppp_softcs.lock);
LIST_FOREACH(scf, &ppp_softcs.list, sc_iflist) {
if (scf->sc_xfer == pid) {
scf->sc_xfer = 0;
mutex_exit(&ppp_softcs.lock);
return scf;
}
if (scf->sc_devp == NULL && sc == NULL)
sc = scf;
}
mutex_exit(&ppp_softcs.lock);

if (sc == NULL)
sc = ppp_create(ppp_cloner.ifc_name, -1);

sc->sc_si = softint_establish(SOFTINT_NET, pppintr, sc);
if (sc->sc_si == NULL) {
printf("%s: unable to establish softintr\n",
sc->sc_if.if_xname);
return NULL;
}
sc->sc_flags = 0;
sc->sc_mru = PPP_MRU;
sc->sc_relinq = NULL;
(void)memset(&sc->sc_stats, 0, sizeof(sc->sc_stats));
#ifdef VJC
sc->sc_comp = malloc(sizeof(struct slcompress), M_DEVBUF, M_NOWAIT);
if (sc->sc_comp)
sl_compress_init(sc->sc_comp);
#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_second;

return sc;
}

/*
* Deallocate a ppp unit. Must be called at splsoftnet or higher.
*/
void
pppdealloc(struct ppp_softc *sc)
{
struct mbuf *m;

softint_disestablish(sc->sc_si);
if_down(&sc->sc_if);
sc->sc_if.if_flags &= ~(IFF_UP|IFF_RUNNING);
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);
}
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 */
#ifdef PPP_FILTER
if (sc->sc_pass_filt_in.bf_insns != 0) {
free(sc->sc_pass_filt_in.bf_insns, M_DEVBUF);
sc->sc_pass_filt_in.bf_insns = 0;
sc->sc_pass_filt_in.bf_len = 0;
}
if (sc->sc_pass_filt_out.bf_insns != 0) {
free(sc->sc_pass_filt_out.bf_insns, M_DEVBUF);
sc->sc_pass_filt_out.bf_insns = 0;
sc->sc_pass_filt_out.bf_len = 0;
}
if (sc->sc_active_filt_in.bf_insns != 0) {
free(sc->sc_active_filt_in.bf_insns, M_DEVBUF);
sc->sc_active_filt_in.bf_insns = 0;
sc->sc_active_filt_in.bf_len = 0;
}
if (sc->sc_active_filt_out.bf_insns != 0) {
free(sc->sc_active_filt_out.bf_insns, M_DEVBUF);
sc->sc_active_filt_out.bf_insns = 0;
sc->sc_active_filt_out.bf_len = 0;
}
#endif /* PPP_FILTER */
#ifdef VJC
if (sc->sc_comp != 0) {
free(sc->sc_comp, M_DEVBUF);
sc->sc_comp = 0;
}
#endif
(void)ppp_clone_destroy(&sc->sc_if);
}

/*
* Ioctl routine for generic ppp devices.
*/
int
pppioctl(struct ppp_softc *sc, u_long cmd, void *data, int flag,
struct lwp *l)
{
int s, error, flags, mru, npx;
u_int nb;
struct ppp_option_data *odp;
struct compressor *cp;
struct npioctl *npi;
time_t t;
#ifdef PPP_FILTER
struct bpf_program *bp, *nbp;
struct bpf_insn *newcode, *oldcode;
int newcodelen;
#endif /* PPP_FILTER */
#ifdef PPP_COMPRESS
u_char ccp_option[CCP_MAX_OPTION_LENGTH];
#endif

switch (cmd) {
case PPPIOCSFLAGS:
case PPPIOCSMRU:
case PPPIOCSMAXCID:
case PPPIOCSCOMPRESS:
case PPPIOCSNPMODE:
if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE,
KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, &sc->sc_if,
KAUTH_ARG(cmd), NULL) != 0)
return EPERM;
break;
case PPPIOCXFERUNIT:
/* XXX: Why is this privileged?! */
if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE,
KAUTH_REQ_NETWORK_INTERFACE_GETPRIV, &sc->sc_if,
KAUTH_ARG(cmd), NULL) != 0)
return EPERM;
break;
default:
break;
}

switch (cmd) {
case FIONREAD:
*(int *)data = sc->sc_inq.ifq_len;
break;

case PPPIOCGUNIT:
*(int *)data = sc->sc_unit;
break;

case PPPIOCGFLAGS:
*(u_int *)data = sc->sc_flags;
break;

case PPPIOCGRAWIN:
{
struct ppp_rawin *rwin = (struct ppp_rawin *)data;
u_char c, q = 0;

for (c = sc->sc_rawin_start; c < sizeof(sc->sc_rawin.buf);)
rwin->buf[q++] = sc->sc_rawin.buf[c++];

for (c = 0; c < sc->sc_rawin_start;)
rwin->buf[q++] = sc->sc_rawin.buf[c++];

rwin->count = sc->sc_rawin.count;
}
break;

case PPPIOCSFLAGS:
flags = *(int *)data & SC_MASK;
s = splsoftnet();
#ifdef PPP_COMPRESS
if (sc->sc_flags & SC_CCP_OPEN && !(flags & SC_CCP_OPEN))
ppp_ccp_closed(sc);
#endif
splhigh(); /* XXX IMP ME HARDER */
sc->sc_flags = (sc->sc_flags & ~SC_MASK) | flags;
splx(s);
break;

case PPPIOCSMRU:
mru = *(int *)data;
if (mru >= PPP_MINMRU && mru <= PPP_MAXMRU)
sc->sc_mru = mru;
break;

case PPPIOCGMRU:
*(int *)data = sc->sc_mru;
break;

#ifdef VJC
case PPPIOCSMAXCID:
if (sc->sc_comp) {
s = splsoftnet();
sl_compress_setup(sc->sc_comp, *(int *)data);
splx(s);
}
break;
#endif

case PPPIOCXFERUNIT:
sc->sc_xfer = l->l_proc->p_pid;
break;

#ifdef PPP_COMPRESS
case PPPIOCSCOMPRESS:
odp = (struct ppp_option_data *)data;
nb = odp->length;
if (nb > sizeof(ccp_option))
nb = sizeof(ccp_option);
if (nb < 3)
return EINVAL;
if ((error = copyin(odp->ptr, ccp_option, nb)) != 0)
return error;
/* preliminary check on the length byte */
if (ccp_option[1] < 2)
return EINVAL;
cp = ppp_get_compressor(ccp_option[0]);
if (cp == NULL) {
if (sc->sc_flags & SC_DEBUG)
printf("%s: no compressor for [%x %x %x], %x\n",
sc->sc_if.if_xname, ccp_option[0],
ccp_option[1], ccp_option[2], nb);
return EINVAL; /* no handler found */
}
/*
* Found a handler for the protocol - try to allocate
* a compressor or decompressor.
*/
error = 0;
if (odp->transmit) {
s = splsoftnet();
if (sc->sc_xc_state != NULL) {
(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
ppp_compressor_rele(sc->sc_xcomp);
}
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("%s: comp_alloc failed\n",
sc->sc_if.if_xname);
error = ENOBUFS;
}
splhigh(); /* XXX IMP ME HARDER */
sc->sc_flags &= ~SC_COMP_RUN;
splx(s);
} else {
s = splsoftnet();
if (sc->sc_rc_state != NULL) {
(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
ppp_compressor_rele(sc->sc_rcomp);
}
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("%s: decomp_alloc failed\n",
sc->sc_if.if_xname);
error = ENOBUFS;
}
splhigh(); /* XXX IMP ME HARDER */
sc->sc_flags &= ~SC_DECOMP_RUN;
splx(s);
}
return error;
#endif /* PPP_COMPRESS */

case PPPIOCGNPMODE:
case PPPIOCSNPMODE:
npi = (struct npioctl *)data;
switch (npi->protocol) {
case PPP_IP:
npx = NP_IP;
break;
case PPP_IPV6:
npx = NP_IPV6;
break;
default:
return EINVAL;
}
if (cmd == PPPIOCGNPMODE) {
npi->mode = sc->sc_npmode[npx];
} else {
if (npi->mode != sc->sc_npmode[npx]) {
s = splnet();
sc->sc_npmode[npx] = npi->mode;
if (npi->mode != NPMODE_QUEUE) {
ppp_requeue(sc);
ppp_restart(sc);
}
splx(s);
}
}
break;

case PPPIOCGIDLE:
s = splsoftnet();
t = time_second;
((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;

#ifdef PPP_FILTER
case PPPIOCSPASS:
case PPPIOCSACTIVE:
/* These are no longer supported. */
return EOPNOTSUPP;

case PPPIOCSIPASS:
case PPPIOCSOPASS:
case PPPIOCSIACTIVE:
case PPPIOCSOACTIVE:
nbp = (struct bpf_program *)data;
if ((unsigned) nbp->bf_len > BPF_MAXINSNS)
return EINVAL;
newcodelen = nbp->bf_len * sizeof(struct bpf_insn);
if (newcodelen != 0) {
newcode = malloc(newcodelen, M_DEVBUF, M_WAITOK);
/* WAITOK -- malloc() never fails. */
if ((error = copyin((void *)nbp->bf_insns,
(void *)newcode, newcodelen)) != 0) {
free(newcode, M_DEVBUF);
return error;
}
if (!bpf_validate(newcode, nbp->bf_len)) {
free(newcode, M_DEVBUF);
return EINVAL;
}
} else
newcode = 0;
switch (cmd) {
case PPPIOCSIPASS:
bp = &sc->sc_pass_filt_in;
break;

case PPPIOCSOPASS:
bp = &sc->sc_pass_filt_out;
break;

case PPPIOCSIACTIVE:
bp = &sc->sc_active_filt_in;
break;

case PPPIOCSOACTIVE:
bp = &sc->sc_active_filt_out;
break;
default:
free(newcode, M_DEVBUF);
return EPASSTHROUGH;
}
oldcode = bp->bf_insns;
s = splnet();
bp->bf_len = nbp->bf_len;
bp->bf_insns = newcode;
splx(s);
if (oldcode != 0)
free(oldcode, M_DEVBUF);
break;
#endif /* PPP_FILTER */

default:
return EPASSTHROUGH;
}
return 0;
}

/*
* Process an ioctl request to the ppp network interface.
*/
static int
pppsioctl(struct ifnet *ifp, u_long cmd, void *data)
{
struct ppp_softc *sc = ifp->if_softc;
struct ifaddr *ifa = (struct ifaddr *)data;
struct ifreq *ifr = (struct ifreq *)data;
struct ppp_stats *psp;
#ifdef PPP_COMPRESS
struct ppp_comp_stats *pcp;
#endif
int s = splnet(), error = 0;

switch (cmd) {
case SIOCSIFFLAGS:
if ((error = ifioctl_common(ifp, cmd, data)) != 0)
break;
if ((ifp->if_flags & IFF_RUNNING) == 0)
ifp->if_flags &= ~IFF_UP;
break;

case SIOCINITIFADDR:
switch (ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef INET6
case AF_INET6:
break;
#endif
default:
printf("%s: af%d not supported\n", ifp->if_xname,
ifa->ifa_addr->sa_family);
error = EAFNOSUPPORT;
break;
}
ifa->ifa_rtrequest = p2p_rtrequest;
break;

case SIOCADDMULTI:
case SIOCDELMULTI:
if (ifr == NULL) {
error = EAFNOSUPPORT;
break;
}
switch (ifreq_getaddr(cmd, ifr)->sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef INET6
case AF_INET6:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;

case SIOCGPPPSTATS:
psp = &((struct ifpppstatsreq *)data)->stats;
memset(psp, 0, sizeof(*psp));
psp->p = sc->sc_stats;
#if defined(VJC) && !defined(SL_NO_STATS)
if (sc->sc_comp) {
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;
memset(pcp, 0, 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:
if ((error = ifioctl_common(&sc->sc_if, cmd, data)) == ENETRESET)
error = 0;
break;
}
splx(s);
return error;
}

/*
* Queue a packet. Start transmission if not active.
* Packet is placed in Information field of PPP frame.
*/
int
pppoutput(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst,
const struct rtentry *rtp)
{
struct ppp_softc *sc = ifp->if_softc;
int protocol, address, control;
u_char *cp;
int s, error;
#ifdef INET
struct ip *ip;
#endif
struct ifqueue *ifq;
enum NPmode mode;
int len;

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;
}

IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family);

/*
* 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 INET6
case AF_INET6:
address = PPP_ALLSTATIONS; /*XXX*/
control = PPP_UI; /*XXX*/
protocol = PPP_IPV6;
mode = sc->sc_npmode[NP_IPV6];

#if 0 /* XXX flowinfo/traffic class, maybe? */
/*
* 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;
#endif
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("%s: af%d not supported\n", ifp->if_xname,
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.
*/
M_PREPEND(m0, PPP_HDRLEN, M_DONTWAIT);
if (m0 == NULL) {
error = ENOBUFS;
goto bad;
}

cp = mtod(m0, u_char *);
*cp++ = address;
*cp++ = control;
*cp++ = protocol >> 8;
*cp++ = protocol & 0xff;

len = m_length(m0);

if (sc->sc_flags & SC_LOG_OUTPKT) {
printf("%s output: ", ifp->if_xname);
pppdumpm(m0);
}

if ((protocol & 0x8000) == 0) {
#ifdef PPP_FILTER
/*
* Apply the pass and active filters to the packet,
* but only if it is a data packet.
*/
if (sc->sc_pass_filt_out.bf_insns != 0 &&
bpf_filter(sc->sc_pass_filt_out.bf_insns,
(u_char *)m0, len, 0) == 0) {
error = 0; /* drop this packet */
goto bad;
}

/*
* Update the time we sent the most recent packet.
*/
if (sc->sc_active_filt_out.bf_insns == 0 ||
bpf_filter(sc->sc_active_filt_out.bf_insns,
(u_char *)m0, len, 0))
sc->sc_last_sent = time_second;
#else
/*
* Update the time we sent the most recent packet.
*/
sc->sc_last_sent = time_second;
#endif /* PPP_FILTER */
}

/*
* See if bpf wants to look at the packet.
*/
bpf_mtap(&sc->sc_if, m0, BPF_D_OUT);

/*
* Put the packet on the appropriate queue.
*/
s = splnet();
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 {
ifq = (m0->m_flags & M_HIGHPRI) ? &sc->sc_fastq : NULL;
if ((error = ifq_enqueue2(&sc->sc_if, ifq, m0)) != 0) {
splx(s);
if_statinc(&sc->sc_if, if_oerrors);
sc->sc_stats.ppp_oerrors++;
return error;
}
ppp_restart(sc);
}
if_statadd2(ifp, if_opackets, 1, if_obytes, len);

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, since we muck with the queues.
*/
static void
ppp_requeue(struct ppp_softc *sc)
{
struct mbuf *m, **mpp;
struct ifqueue *ifq;
enum NPmode mode;
int error;

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;
case PPP_IPV6:
mode = sc->sc_npmode[NP_IPV6];
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 : NULL;
if ((error = ifq_enqueue2(&sc->sc_if, ifq, m)) != 0) {
if_statinc(&sc->sc_if, if_oerrors);
sc->sc_stats.ppp_oerrors++;
}
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;
}

/*
* Transmitter has finished outputting some stuff;
* remember to call sc->sc_start later at splsoftnet.
*/
void
ppp_restart(struct ppp_softc *sc)
{
int s = splhigh(); /* XXX IMP ME HARDER */

sc->sc_flags &= ~SC_TBUSY;
softint_schedule(sc->sc_si);
splx(s);
}

/*
* Get a packet to send. This procedure is intended to be called at
* splsoftnet, since it may involve time-consuming operations such as
* applying VJ compression, packet compression, address/control and/or
* protocol field compression to the packet.
*/
struct mbuf *
ppp_dequeue(struct ppp_softc *sc)
{
struct mbuf *m, *mp;
u_char *cp;
int address, control, protocol;
int s;

/*
* Grab a packet to send: first try the fast queue, then the
* normal queue.
*/
s = splnet();
if (sc->sc_nfastq < sc->sc_maxfastq) {
IF_DEQUEUE(&sc->sc_fastq, m);
if (m != NULL)
sc->sc_nfastq++;
else
IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
} else {
sc->sc_nfastq = 0;
IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
if (m == NULL) {
IF_DEQUEUE(&sc->sc_fastq, m);
if (m != NULL)
sc->sc_nfastq++;
}
}
splx(s);

if (m == NULL)
return NULL;

++sc->sc_stats.ppp_opackets;

/*
* 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:
#ifdef VJC
/*
* If the packet is a TCP/IP packet, see if we can compress it.
*/
if ((sc->sc_flags & SC_COMP_TCP) && sc->sc_comp != NULL) {
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;
}
/* Update protocol in PPP header */
cp[3] = protocol;
}
}
#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;

slen = 0;
for (mp = m; mp != NULL; mp = mp->m_next)
slen += mp->m_len;
(*sc->sc_xcomp->compress)
(sc->sc_xc_state, &mcomp, m, slen, sc->sc_if.if_mtu + PPP_HDRLEN);
if (mcomp != NULL) {
if (sc->sc_flags & SC_CCP_UP) {
/*
* Send the compressed packet instead of the
* original.
*/
m_freem(m);
m = mcomp;
cp = mtod(m, u_char *);
protocol = cp[3];
} else {
/*
* Can't transmit compressed packets until CCP
* is up.
*/
m_freem(mcomp);
}
}
}
#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;
}

return m;
}

/*
* Software interrupt routine, called at splsoftnet.
*/
static void
pppintr(void *arg)
{
struct ppp_softc *sc = arg;
struct mbuf *m;
int s;

mutex_enter(softnet_lock);
if (!(sc->sc_flags & SC_TBUSY) &&
(IFQ_IS_EMPTY(&sc->sc_if.if_snd) == 0 ||
sc->sc_fastq.ifq_head ||
sc->sc_outm)) {
s = splhigh(); /* XXX IMP ME HARDER */
sc->sc_flags |= SC_TBUSY;
splx(s);
(*sc->sc_start)(sc);
}
for (;;) {
s = splnet();
IF_DEQUEUE(&sc->sc_rawq, m);
splx(s);
if (m == NULL)
break;
ppp_inproc(sc, m);
}
mutex_exit(softnet_lock);
}

#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(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 = mtod(mp, u_char *);
} 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 (%p+%x > %p+%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 = splhigh(); /* XXX IMP ME HARDER */
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_unit, 0,
sc->sc_flags & SC_DEBUG)) {
s = splhigh(); /* XXX IMP ME HARDER */
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_unit, 0, sc->sc_mru,
sc->sc_flags & SC_DEBUG)) {
s = splhigh(); /* XXX IMP ME HARDER */
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 = splhigh(); /* XXX IMP ME HARDER */
sc->sc_flags &= ~SC_DC_ERROR;
splx(s);
}
}
}
break;
}
}

/*
* CCP is down; free (de)compressor state if necessary.
*/
static void
ppp_ccp_closed(struct ppp_softc *sc)
{
if (sc->sc_xc_state) {
(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
ppp_compressor_rele(sc->sc_xcomp);
sc->sc_xc_state = NULL;
}
if (sc->sc_rc_state) {
(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
ppp_compressor_rele(sc->sc_rcomp);
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(struct ppp_softc *sc, struct mbuf *m, int lost)
{
int s = splhigh(); /* XXX IMP ME HARDER */

if (lost)
m->m_flags |= M_ERRMARK;
IF_ENQUEUE(&sc->sc_rawq, m);
softint_schedule(sc->sc_si);
splx(s);
}

/*
* Process a received PPP packet, doing decompression as necessary.
* Should be called at splsoftnet.
*/
#define COMPTYPE(proto) \
((proto) == PPP_VJC_COMP ? TYPE_COMPRESSED_TCP \
: TYPE_UNCOMPRESSED_TCP)

static void
ppp_inproc(struct ppp_softc *sc, struct mbuf *m)
{
struct ifnet *ifp = &sc->sc_if;
pktqueue_t *pktq = NULL;
struct ifqueue *inq = NULL;
int s, ilen, proto, rv;
u_char *cp, adrs, ctrl;
struct mbuf *mp, *dmp = NULL;
#ifdef VJC
int xlen;
u_char *iphdr;
u_int hlen;
#endif

sc->sc_stats.ppp_ipackets++;

if (sc->sc_flags & SC_LOG_INPKT) {
ilen = 0;
for (mp = m; mp != NULL; mp = mp->m_next)
ilen += mp->m_len;
printf("%s: got %d bytes\n", ifp->if_xname, 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 = splhigh(); /* XXX IMP ME HARDER */
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("%s: decompress failed %d\n",
ifp->if_xname, rv);
s = splhigh(); /* XXX IMP ME HARDER */
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.
*/
if (sc->sc_comp)
sl_uncompress_tcp(NULL, 0, TYPE_ERROR, sc->sc_comp);
s = splhigh(); /* XXX IMP ME HARDER */
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) || sc->sc_comp == 0)
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("%s: VJ uncompress failed"
" on type comp\n",
ifp->if_xname);
}
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) {
/* Lose if big headers and no clusters */
m_freem(mp);
goto bad;
}
}
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;
mp->m_next = m_free(m);
} else
mp->m_next = m;
m = mp;
ilen += hlen - xlen;

} else if (proto == PPP_VJC_UNCOMP) {
if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
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("%s: VJ uncompress failed"
" on type uncomp\n",
ifp->if_xname);
}
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->m_flags & M_EXT)) {
MGETHDR(mp, M_DONTWAIT, MT_DATA);
if (mp != NULL) {
m_copydata(m, 0, ilen, mtod(mp, void *));
m_freem(m);
m = mp;
m->m_len = ilen;
}
}
m->m_pkthdr.len = ilen;
m_set_rcvif(m, ifp);

if ((proto & 0x8000) == 0) {
#ifdef PPP_FILTER
/*
* See whether we want to pass this packet, and
* if it counts as link activity.
*/
if (sc->sc_pass_filt_in.bf_insns != 0 &&
bpf_filter(sc->sc_pass_filt_in.bf_insns,
(u_char *)m, ilen, 0) == 0) {
/* drop this packet */
m_freem(m);
return;
}
if (sc->sc_active_filt_in.bf_insns == 0 ||
bpf_filter(sc->sc_active_filt_in.bf_insns,
(u_char *)m, ilen, 0))
sc->sc_last_recv = time_second;
#else
/*
* Record the time that we received this packet.
*/
sc->sc_last_recv = time_second;
#endif /* PPP_FILTER */
}

/* See if bpf wants to look at the packet. */
bpf_mtap(&sc->sc_if, m, BPF_D_IN);

switch (proto) {
#ifdef INET
case PPP_IP:
/*
* IP packet - take off the ppp header and pass it up to IP.
*/
if ((ifp->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;
#ifdef GATEWAY
if (ipflow_fastforward(m))
return;
#endif
pktq = ip_pktq;
break;
#endif

#ifdef INET6
case PPP_IPV6:
/*
* IPv6 packet - take off the ppp header and pass it up to
* IPv6.
*/
if ((ifp->if_flags & IFF_UP) == 0 ||
sc->sc_npmode[NP_IPV6] != 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;
#ifdef GATEWAY
if (ip6flow_fastforward(&m))
return;
#endif
pktq = ip6_pktq;
break;
#endif

default:
/*
* Some other protocol - place on input queue for read().
*/
inq = &sc->sc_inq;
pktq = NULL;
break;
}

/*
* Put the packet on the appropriate input queue.
*/
s = splnet();

/* pktq: inet or inet6 cases */
if (__predict_true(pktq)) {
if (__predict_false(!pktq_enqueue(pktq, m, 0))) {
splx(s);
if_statinc(ifp, if_iqdrops);
goto bad;
}
if_statadd2(ifp, if_ipackets, 1, if_ibytes, ilen);
splx(s);
return;
}

/* ifq: other protocol cases */
if (!inq) {
splx(s);
goto bad;
}
if (IF_QFULL(inq)) {
IF_DROP(inq);
splx(s);
if (sc->sc_flags & SC_DEBUG)
printf("%s: input queue full\n", ifp->if_xname);
if_statinc(ifp, if_iqdrops);
goto bad;
}
IF_ENQUEUE(inq, m);
splx(s);
if_statadd2(ifp, if_ipackets, 1, if_ibytes, ilen);

(*sc->sc_ctlp)(sc);

return;

bad:
m_freem(m);
if_statinc(&sc->sc_if, if_ierrors);
sc->sc_stats.ppp_ierrors++;
}

#define MAX_DUMP_BYTES 128

static void
pppdumpm(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;
/* Convert byte to ascii hex */
*bp++ = hexdigits[*rptr >> 4];
*bp++ = hexdigits[*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);
}

#ifdef ALTQ
/*
* A wrapper to transmit a packet from if_start since ALTQ uses
* if_start to send a packet.
*/
static void
ppp_ifstart(struct ifnet *ifp)
{
struct ppp_softc *sc;

sc = ifp->if_softc;
(*sc->sc_start)(sc);
}
#endif

static const struct ppp_known_compressor {
uint8_t code;
const char *module;
} ppp_known_compressors[] = {
{ CI_DEFLATE, "ppp_deflate" },
{ CI_DEFLATE_DRAFT, "ppp_deflate" },
{ CI_BSD_COMPRESS, "ppp_bsdcomp" },
{ CI_MPPE, "ppp_mppe" },
{ 0, NULL }
};

static int
ppp_compressor_init(void)
{

mutex_init(&ppp_compressors_mtx, MUTEX_DEFAULT, IPL_NONE);
return 0;
}

static int
ppp_compressor_destroy(void)
{

mutex_destroy(&ppp_compressors_mtx);
return 0;
}

static void
ppp_compressor_rele(struct compressor *cp)
{

mutex_enter(&ppp_compressors_mtx);
--cp->comp_refcnt;
mutex_exit(&ppp_compressors_mtx);
}

static struct compressor *
ppp_get_compressor_noload(uint8_t ci, bool hold)
{
struct compressor *cp;

KASSERT(mutex_owned(&ppp_compressors_mtx));
LIST_FOREACH(cp, &ppp_compressors, comp_list) {
if (cp->compress_proto == ci) {
if (hold)
++cp->comp_refcnt;
return cp;
}
}

return NULL;
}

static struct compressor *
ppp_get_compressor(uint8_t ci)
{
struct compressor *cp = NULL;
const struct ppp_known_compressor *pkc;

mutex_enter(&ppp_compressors_mtx);
cp = ppp_get_compressor_noload(ci, true);
mutex_exit(&ppp_compressors_mtx);
if (cp != NULL)
return cp;

kernconfig_lock();
mutex_enter(&ppp_compressors_mtx);
cp = ppp_get_compressor_noload(ci, true);
mutex_exit(&ppp_compressors_mtx);
if (cp == NULL) {
/* Not found, so try to autoload a module */
for (pkc = ppp_known_compressors; pkc->module != NULL; pkc++) {
if (pkc->code == ci) {
if (module_autoload(pkc->module,
MODULE_CLASS_MISC) != 0)
break;
mutex_enter(&ppp_compressors_mtx);
cp = ppp_get_compressor_noload(ci, true);
mutex_exit(&ppp_compressors_mtx);
break;
}
}
}
kernconfig_unlock();

return cp;
}

int
ppp_register_compressor(struct compressor *pc, size_t ncomp)
{
int error = 0;
size_t i;

mutex_enter(&ppp_compressors_mtx);
for (i = 0; i < ncomp; i++) {
if (ppp_get_compressor_noload(pc[i].compress_proto,
false) != NULL)
error = EEXIST;
}
if (!error) {
for (i = 0; i < ncomp; i++) {
pc[i].comp_refcnt = 0;
LIST_INSERT_HEAD(&ppp_compressors, &pc[i], comp_list);
}
}
mutex_exit(&ppp_compressors_mtx);

return error;
}

int
ppp_unregister_compressor(struct compressor *pc, size_t ncomp)
{
int error = 0;
size_t i;

mutex_enter(&ppp_compressors_mtx);
for (i = 0; i < ncomp; i++) {
if (ppp_get_compressor_noload(pc[i].compress_proto,
false) != &pc[i])
error = ENOENT;
else if (pc[i].comp_refcnt != 0)
error = EBUSY;
}
if (!error) {
for (i = 0; i < ncomp; i++) {
LIST_REMOVE(&pc[i], comp_list);
}
}
mutex_exit(&ppp_compressors_mtx);

return error;
}

/*
* Module infrastructure
*/
#include "if_module.h"

#ifdef PPP_FILTER
#define PPP_DEP "bpf_filter,"
#else
#define PPP_DEP
#endif

IF_MODULE(MODULE_CLASS_DRIVER, ppp, PPP_DEP "slcompress")