freebsd-dev/sys/net/if_spppfr.c

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/*-
* Synchronous Frame Relay link level subroutines.
* ANSI T1.617-compaible link management signaling
* implemented for Frame Relay mode.
* Cisco-type Frame Relay framing added, thanks Alex Tutubalin.
* Only one DLCI per channel for now.
*
* Copyright (C) 1994-2000 Cronyx Engineering.
* Author: Serge Vakulenko, <vak@cronyx.ru>
*
* Copyright (C) 1999-2004 Cronyx Engineering.
* Author: Kurakin Roman, <rik@cronyx.ru>
*
* This software is distributed with NO WARRANTIES, not even the implied
* warranties for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Authors grant any other persons or organisations a permission to use,
* modify and redistribute this software in source and binary forms,
* as long as this message is kept with the software, all derivative
* works or modified versions.
*
* $Cronyx Id: if_spppfr.c,v 1.1.2.10 2004/06/29 09:02:30 rik Exp $
* $FreeBSD$
*/
#include <sys/param.h>
#if defined(__FreeBSD__)
#include "opt_inet.h"
#include "opt_inet6.h"
#endif
#ifdef NetBSD1_3
# if NetBSD1_3 > 6
# include "opt_inet.h"
# include "opt_inet6.h"
# include "opt_iso.h"
# endif
#endif
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/sockio.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#if defined(__FreeBSD__)
#include <sys/random.h>
#endif
#include <sys/malloc.h>
#include <sys/mbuf.h>
#if defined (__OpenBSD__)
#include <sys/md5k.h>
#else
#include <sys/md5.h>
#endif
#include <net/if.h>
#include <net/if_var.h>
#include <net/netisr.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <net/slcompress.h>
#if defined (__NetBSD__) || defined (__OpenBSD__)
#include <machine/cpu.h> /* XXX for softnet */
#endif
#include <machine/stdarg.h>
#include <netinet/in_var.h>
#ifdef INET
#include <netinet/ip.h>
#include <netinet/tcp.h>
#endif
#if defined (__FreeBSD__) || defined (__OpenBSD__)
# include <netinet/if_ether.h>
#else
# include <net/ethertypes.h>
#endif
#include <net/if_sppp.h>
/*
* Frame Relay.
*/
#define FR_UI 0x03 /* Unnumbered Information */
#define FR_IP 0xCC /* IP protocol identifier */
#define FR_PADDING 0x00 /* NLPID padding */
#define FR_SIGNALING 0x08 /* Q.933/T1.617 signaling identifier */
#define FR_SNAP 0x80 /* NLPID snap */
/*
* Header flags.
*/
#define FR_DE 0x02 /* discard eligibility */
#define FR_FECN 0x04 /* forward notification */
#define FR_BECN 0x08 /* backward notification */
/*
* Signaling message types.
*/
#define FR_MSG_ENQUIRY 0x75 /* status enquiry */
#define FR_MSG_STATUS 0x7d /* status */
#define FR_ENQUIRY_SIZE 14
/*
* Message field types.
*/
#define FR_FLD_RTYPE 0x01 /* report type */
#define FR_FLD_VERIFY 0x03 /* link verification */
#define FR_FLD_PVC 0x07 /* PVC status */
#define FR_FLD_LSHIFT5 0x95 /* locking shift 5 */
/*
* Report types.
*/
#define FR_RTYPE_FULL 0 /* full status */
#define FR_RTYPE_SHORT 1 /* link verification only */
#define FR_RTYPE_SINGLE 2 /* single PVC status */
/* PVC status field. */
#define FR_DLCI_DELETE 0x04 /* PVC is deleted */
#define FR_DLCI_ACTIVE 0x02 /* PVC is operational */
#define FR_DLCI_NEW 0x08 /* PVC is new */
struct arp_req {
unsigned short htype; /* hardware type = ARPHRD_FRELAY */
unsigned short ptype; /* protocol type = ETHERTYPE_IP */
unsigned char halen; /* hardware address length = 2 */
unsigned char palen; /* protocol address length = 4 */
unsigned short op; /* ARP/RARP/InARP request/reply */
unsigned short hsource; /* hardware source address */
unsigned short psource1; /* protocol source */
unsigned short psource2;
unsigned short htarget; /* hardware target address */
unsigned short ptarget1; /* protocol target */
unsigned short ptarget2;
} __packed;
#if defined(__FreeBSD__) && __FreeBSD_version < 501113
#define SPP_FMT "%s%d: "
#define SPP_ARGS(ifp) (ifp)->if_name, (ifp)->if_unit
#else
#define SPP_FMT "%s: "
#define SPP_ARGS(ifp) (ifp)->if_xname
#endif
/* almost every function needs these */
#define STDDCL \
struct ifnet *ifp = SP2IFP(sp); \
int debug = ifp->if_flags & IFF_DEBUG
static void sppp_fr_arp (struct sppp *sp, struct arp_req *req, u_short addr);
static void sppp_fr_signal (struct sppp *sp, unsigned char *h, int len);
void sppp_fr_input (struct sppp *sp, struct mbuf *m)
{
STDDCL;
u_char *h = mtod (m, u_char*);
int isr = -1;
int dlci, hlen, proto;
/* Get the DLCI number. */
if (m->m_pkthdr.len < 10) {
bad: m_freem (m);
return;
}
dlci = (h[0] << 2 & 0x3f0) | (h[1] >> 4 & 0x0f);
/* Process signaling packets. */
if (dlci == 0) {
sppp_fr_signal (sp, h, m->m_pkthdr.len);
m_freem (m);
return;
}
if (dlci != sp->fr_dlci) {
if (debug)
printf (SPP_FMT "Received packet from invalid DLCI %d\n",
SPP_ARGS(ifp), dlci);
goto bad;
}
/* Process the packet. */
if (ntohs (*(short*) (h+2)) == ETHERTYPE_IP) {
/* Prehistoric IP framing? */
h[2] = FR_UI;
h[3] = FR_IP;
}
if (h[2] != FR_UI) {
if (debug)
printf (SPP_FMT "Invalid frame relay header flag 0x%02x\n",
SPP_ARGS(ifp), h[2]);
goto bad;
}
switch (h[3]) {
default:
if (debug)
printf (SPP_FMT "Unsupported NLPID 0x%02x\n",
SPP_ARGS(ifp), h[3]);
goto bad;
case FR_PADDING:
if (h[4] != FR_SNAP) {
if (debug)
printf (SPP_FMT "Bad NLPID 0x%02x\n",
SPP_ARGS(ifp), h[4]);
goto bad;
}
if (h[5] || h[6] || h[7]) {
if (debug)
printf (SPP_FMT "Bad OID 0x%02x-0x%02x-0x%02x\n",
SPP_ARGS(ifp),
h[5], h[6], h[7]);
goto bad;
}
proto = ntohs (*(short*) (h+8));
if (proto == ETHERTYPE_ARP) {
/* Process the ARP request. */
if (m->m_pkthdr.len != 10 + sizeof (struct arp_req)) {
if (debug)
printf (SPP_FMT "Bad ARP request size = %d bytes\n",
SPP_ARGS(ifp),
m->m_pkthdr.len);
goto bad;
}
sppp_fr_arp (sp, (struct arp_req*) (h + 10),
h[0] << 8 | h[1]);
m_freem (m);
return;
}
hlen = 10;
break;
case FR_IP:
proto = ETHERTYPE_IP;
hlen = 4;
break;
}
/* Remove frame relay header. */
m_adj (m, hlen);
switch (proto) {
default:
if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1);
drop: if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
m_freem (m);
return;
#ifdef INET
case ETHERTYPE_IP:
isr = NETISR_IP;
break;
#endif
}
if (! (ifp->if_flags & IFF_UP))
goto drop;
M_SETFIB(m, ifp->if_fib);
/* Check queue. */
if (netisr_queue(isr, m)) { /* (0) on success. */
if (debug)
log(LOG_DEBUG, SPP_FMT "protocol queue overflow\n",
SPP_ARGS(ifp));
}
}
/*
* Add the frame relay header to the packet.
* For IP the header length is 4 bytes,
* for all other protocols - 10 bytes (RFC 1490).
*/
struct mbuf *sppp_fr_header (struct sppp *sp, struct mbuf *m,
int family)
{
STDDCL;
u_char *h;
int type, hlen;
/* Prepend the space for Frame Relay header. */
hlen = (family == AF_INET) ? 4 : 10;
M_PREPEND (m, hlen, M_NOWAIT);
if (! m)
return 0;
h = mtod (m, u_char*);
/* Fill the header. */
h[0] = sp->fr_dlci >> 2 & 0xfc;
h[1] = sp->fr_dlci << 4 | 1;
h[2] = FR_UI;
switch (family) {
default:
if (debug)
printf (SPP_FMT "Cannot handle address family %d\n",
SPP_ARGS(ifp), family);
m_freem (m);
return 0;
#ifdef INET
case AF_INET:
#if 0 /* Crashes on fragmented packets */
/*
* Set the discard eligibility bit, if:
* 1) no fragmentation
* 2) length > 400 bytes
* 3a) the protocol is UDP or
* 3b) TCP data (no control bits)
*/
{
struct ip *ip = (struct ip*) (h + hlen);
struct tcphdr *tcp = (struct tcphdr*) ((long*)ip + ip->ip_hl);
if (! (ip->ip_off & ~IP_DF) && ip->ip_len > 400 &&
(ip->ip_p == IPPROTO_UDP ||
ip->ip_p == IPPROTO_TCP && ! tcp->th_flags))
h[1] |= FR_DE;
}
#endif
h[3] = FR_IP;
return m;
#endif
#ifdef NS
case AF_NS:
type = 0x8137;
break;
#endif
}
h[3] = FR_PADDING;
h[4] = FR_SNAP;
h[5] = 0;
h[6] = 0;
h[7] = 0;
*(short*) (h+8) = htons(type);
return m;
}
/*
* Send periodical frame relay link verification messages via DLCI 0.
* Called every 10 seconds (default value of T391 timer is 10 sec).
* Every 6-th message is a full status request
* (default value of N391 counter is 6).
*/
void sppp_fr_keepalive (struct sppp *sp)
{
STDDCL;
unsigned char *h, *p;
struct mbuf *m;
MGETHDR (m, M_NOWAIT, MT_DATA);
if (! m)
return;
m->m_pkthdr.rcvif = 0;
h = mtod (m, u_char*);
p = h;
*p++ = 0; /* DLCI = 0 */
*p++ = 1;
*p++ = FR_UI;
*p++ = FR_SIGNALING; /* NLPID = UNI call control */
*p++ = 0; /* call reference length = 0 */
*p++ = FR_MSG_ENQUIRY; /* message type = status enquiry */
*p++ = FR_FLD_LSHIFT5; /* locking shift 5 */
*p++ = FR_FLD_RTYPE; /* report type field */
*p++ = 1; /* report type length = 1 */
if (sp->pp_seq[IDX_LCP] % 6)
*p++ = FR_RTYPE_SHORT; /* link verification only */
else
*p++ = FR_RTYPE_FULL; /* full status needed */
if (sp->pp_seq[IDX_LCP] >= 255)
sp->pp_seq[IDX_LCP] = 0;
*p++ = FR_FLD_VERIFY; /* link verification type field */
*p++ = 2; /* link verification field length = 2 */
*p++ = ++sp->pp_seq[IDX_LCP]; /* our sequence number */
*p++ = sp->pp_rseq[IDX_LCP]; /* last received sequence number */
m->m_pkthdr.len = m->m_len = p - h;
if (debug)
printf (SPP_FMT "send lmi packet, seq=%d, rseq=%d\n",
SPP_ARGS(ifp), (u_char) sp->pp_seq[IDX_LCP],
(u_char) sp->pp_rseq[IDX_LCP]);
if (! IF_HANDOFF_ADJ(&sp->pp_cpq, m, ifp, 3))
if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
}
/*
* Process the frame relay Inverse ARP request.
*/
static void sppp_fr_arp (struct sppp *sp, struct arp_req *req,
u_short his_hardware_address)
{
STDDCL;
struct mbuf *m;
struct arp_req *reply;
u_char *h;
u_short my_hardware_address;
u_long his_ip_address, my_ip_address;
if ((ntohs (req->htype) != ARPHRD_FRELAY ||
ntohs (req->htype) != 16) || /* for BayNetworks routers */
ntohs (req->ptype) != ETHERTYPE_IP) {
if (debug)
printf (SPP_FMT "Invalid ARP hardware/protocol type = 0x%x/0x%x\n",
SPP_ARGS(ifp),
ntohs (req->htype), ntohs (req->ptype));
return;
}
if (req->halen != 2 || req->palen != 4) {
if (debug)
printf (SPP_FMT "Invalid ARP hardware/protocol address length = %d/%d\n",
SPP_ARGS(ifp),
req->halen, req->palen);
return;
}
switch (ntohs (req->op)) {
default:
if (debug)
printf (SPP_FMT "Invalid ARP op = 0x%x\n",
SPP_ARGS(ifp), ntohs (req->op));
return;
case ARPOP_INVREPLY:
/* Ignore. */
return;
case ARPOP_INVREQUEST:
my_hardware_address = ntohs (req->htarget);
his_ip_address = ntohs (req->psource1) << 16 |
ntohs (req->psource2);
my_ip_address = ntohs (req->ptarget1) << 16 |
ntohs (req->ptarget2);
break;
}
if (debug)
printf (SPP_FMT "got ARP request, source=0x%04x/%d.%d.%d.%d, target=0x%04x/%d.%d.%d.%d\n",
SPP_ARGS(ifp), ntohs (req->hsource),
(unsigned char) (his_ip_address >> 24),
(unsigned char) (his_ip_address >> 16),
(unsigned char) (his_ip_address >> 8),
(unsigned char) his_ip_address,
my_hardware_address,
(unsigned char) (my_ip_address >> 24),
(unsigned char) (my_ip_address >> 16),
(unsigned char) (my_ip_address >> 8),
(unsigned char) my_ip_address);
sppp_get_ip_addrs (sp, &my_ip_address, 0, 0);
if (! my_ip_address)
return; /* nothing to reply */
if (debug)
printf (SPP_FMT "send ARP reply, source=0x%04x/%d.%d.%d.%d, target=0x%04x/%d.%d.%d.%d\n",
SPP_ARGS(ifp), my_hardware_address,
(unsigned char) (my_ip_address >> 24),
(unsigned char) (my_ip_address >> 16),
(unsigned char) (my_ip_address >> 8),
(unsigned char) my_ip_address,
his_hardware_address,
(unsigned char) (his_ip_address >> 24),
(unsigned char) (his_ip_address >> 16),
(unsigned char) (his_ip_address >> 8),
(unsigned char) his_ip_address);
/* Send the Inverse ARP reply. */
MGETHDR (m, M_NOWAIT, MT_DATA);
if (! m)
return;
m->m_pkthdr.len = m->m_len = 10 + sizeof (*reply);
m->m_pkthdr.rcvif = 0;
h = mtod (m, u_char*);
reply = (struct arp_req*) (h + 10);
h[0] = his_hardware_address >> 8;
h[1] = his_hardware_address;
h[2] = FR_UI;
h[3] = FR_PADDING;
h[4] = FR_SNAP;
h[5] = 0;
h[6] = 0;
h[7] = 0;
*(short*) (h+8) = htons (ETHERTYPE_ARP);
reply->htype = htons (ARPHRD_FRELAY);
reply->ptype = htons (ETHERTYPE_IP);
reply->halen = 2;
reply->palen = 4;
reply->op = htons (ARPOP_INVREPLY);
reply->hsource = htons (my_hardware_address);
reply->psource1 = htonl (my_ip_address);
reply->psource2 = htonl (my_ip_address) >> 16;
reply->htarget = htons (his_hardware_address);
reply->ptarget1 = htonl (his_ip_address);
reply->ptarget2 = htonl (his_ip_address) >> 16;
if (! IF_HANDOFF_ADJ(&sp->pp_cpq, m, ifp, 3))
if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
}
/*
* Process the input signaling packet (DLCI 0).
* The implemented protocol is ANSI T1.617 Annex D.
*/
static void sppp_fr_signal (struct sppp *sp, unsigned char *h, int len)
{
STDDCL;
u_char *p;
int dlci;
if (h[2] != FR_UI || h[3] != FR_SIGNALING || h[4] != 0) {
if (debug)
printf (SPP_FMT "Invalid signaling header\n",
SPP_ARGS(ifp));
bad: if (debug) {
printf ("%02x", *h++);
while (--len > 0)
printf ("-%02x", *h++);
printf ("\n");
}
return;
}
if (h[5] == FR_MSG_ENQUIRY) {
if (len == FR_ENQUIRY_SIZE &&
h[12] == (u_char) sp->pp_seq[IDX_LCP]) {
sp->pp_seq[IDX_LCP] = random();
printf (SPP_FMT "loopback detected\n",
SPP_ARGS(ifp));
}
return;
}
if (h[5] != FR_MSG_STATUS) {
if (debug)
printf (SPP_FMT "Unknown signaling message: 0x%02x\n",
SPP_ARGS(ifp), h[5]);
goto bad;
}
/* Parse message fields. */
for (p=h+6; p<h+len; ) {
switch (*p) {
default:
if (debug)
printf (SPP_FMT "Unknown signaling field 0x%x\n",
SPP_ARGS(ifp), *p);
break;
case FR_FLD_LSHIFT5:
case FR_FLD_RTYPE:
/* Ignore. */
break;
case FR_FLD_VERIFY:
if (p[1] != 2) {
if (debug)
printf (SPP_FMT "Invalid signaling verify field length %d\n",
SPP_ARGS(ifp), p[1]);
break;
}
sp->pp_rseq[IDX_LCP] = p[2];
if (debug) {
printf (SPP_FMT "got lmi reply rseq=%d, seq=%d",
SPP_ARGS(ifp), p[2], p[3]);
if (p[3] != (u_char) sp->pp_seq[IDX_LCP])
printf (" (really %d)",
(u_char) sp->pp_seq[IDX_LCP]);
printf ("\n");
}
break;
case FR_FLD_PVC:
if (p[1] < 3) {
if (debug)
printf (SPP_FMT "Invalid PVC status length %d\n",
SPP_ARGS(ifp), p[1]);
break;
}
dlci = (p[2] << 4 & 0x3f0) | (p[3] >> 3 & 0x0f);
if (! sp->fr_dlci)
sp->fr_dlci = dlci;
if (sp->fr_status != p[4])
printf (SPP_FMT "DLCI %d %s%s\n",
SPP_ARGS(ifp), dlci,
p[4] & FR_DLCI_DELETE ? "deleted" :
p[4] & FR_DLCI_ACTIVE ? "active" : "passive",
p[4] & FR_DLCI_NEW ? ", new" : "");
sp->fr_status = p[4];
break;
}
if (*p & 0x80)
++p;
else if (p < h+len+1 && p[1])
p += 2 + p[1];
else {
if (debug)
printf (SPP_FMT "Invalid signaling field 0x%x\n",
SPP_ARGS(ifp), *p);
goto bad;
}
}
}