Generic HDLC layer
Krzysztof Halasa <khc@pm.waw.pl>
-January, 2003
Generic HDLC layer currently supports:
-- Frame Relay (ANSI, CCITT and no LMI), with ARP support (no InARP).
- Normal (routed) and Ethernet-bridged (Ethernet device emulation)
- interfaces can share a single PVC.
-- raw HDLC - either IP (IPv4) interface or Ethernet device emulation.
-- Cisco HDLC,
-- PPP (uses syncppp.c),
-- X.25 (uses X.25 routines).
-
-There are hardware drivers for the following cards:
-- C101 by Moxa Technologies Co., Ltd.
-- RISCom/N2 by SDL Communications Inc.
-- and others, some not in the official kernel.
+1. Frame Relay (ANSI, CCITT, Cisco and no LMI).
+ - Normal (routed) and Ethernet-bridged (Ethernet device emulation)
+ interfaces can share a single PVC.
+ - ARP support (no InARP support in the kernel - there is an
+ experimental InARP user-space daemon available on:
+ http://www.kernel.org/pub/linux/utils/net/hdlc/).
+2. raw HDLC - either IP (IPv4) interface or Ethernet device emulation.
+3. Cisco HDLC.
+4. PPP (uses syncppp.c).
+5. X.25 (uses X.25 routines).
+
+Generic HDLC is a protocol driver only - it needs a low-level driver
+for your particular hardware.
Ethernet device emulation (using HDLC or Frame-Relay PVC) is compatible
with IEEE 802.1Q (VLANs) and 802.1D (Ethernet bridging).
Make sure the hdlc.o and the hardware driver are loaded. It should
create a number of "hdlc" (hdlc0 etc) network devices, one for each
WAN port. You'll need the "sethdlc" utility, get it from:
- http://hq.pm.waw.pl/hdlc/
+ http://www.kernel.org/pub/linux/utils/net/hdlc/
Compile sethdlc.c utility:
gcc -O2 -Wall -o sethdlc sethdlc.c
* v35 | rs232 | x21 | t1 | e1 - sets physical interface for a given port
if the card has software-selectable interfaces
loopback - activate hardware loopback (for testing only)
-* clock ext - external clock (uses DTE RX and TX clock)
-* clock int - internal clock (provides clock signal on DCE clock output)
-* clock txint - TX internal, RX external (provides TX clock on DCE output)
-* clock txfromrx - TX clock derived from RX clock (TX clock on DCE output)
-* rate - sets clock rate in bps (not required for external clock or
- for txfromrx)
+* clock ext - both RX clock and TX clock external
+* clock int - both RX clock and TX clock internal
+* clock txint - RX clock external, TX clock internal
+* clock txfromrx - RX clock external, TX clock derived from RX clock
+* rate - sets clock rate in bps (for "int" or "txint" clock only)
+
Setting protocol:
* x25 - sets X.25 mode
* fr - Frame Relay mode
- lmi ansi / ccitt / none - LMI (link management) type
+ lmi ansi / ccitt / cisco / none - LMI (link management) type
dce - Frame Relay DCE (network) side LMI instead of default DTE (user).
It has nothing to do with clocks!
t391 - link integrity verification polling timer (in seconds) - user
-If you have a problem with N2 or C101 card, you can issue the "private"
-command to see port's packet descriptor rings (in kernel logs):
+If you have a problem with N2, C101 or PLX200SYN card, you can issue the
+"private" command to see port's packet descriptor rings (in kernel logs):
sethdlc hdlc0 private
-The hardware driver has to be build with CONFIG_HDLC_DEBUG_RINGS.
+The hardware driver has to be build with #define DEBUG_RINGS.
Attaching this info to bug reports would be helpful. Anyway, let me know
if you have problems using this.
-For patches and other info look at http://hq.pm.waw.pl/hdlc/
+For patches and other info look at:
+<http://www.kernel.org/pub/linux/utils/net/hdlc/>.
* Generic HDLC support routines for Linux
* Frame Relay support
*
- * Copyright (C) 1999 - 2003 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 1999 - 2005 Krzysztof Halasa <khc@pm.waw.pl>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License
active = open and "link reliable"
exist = new = not used
+ CCITT LMI: ITU-T Q.933 Annex A
+ ANSI LMI: ANSI T1.617 Annex D
+ CISCO LMI: the original, aka "Gang of Four" LMI
+
*/
#include <linux/module.h>
#undef DEBUG_ECN
#undef DEBUG_LINK
-#define MAXLEN_LMISTAT 20 /* max size of status enquiry frame */
-
-#define PVC_STATE_NEW 0x01
-#define PVC_STATE_ACTIVE 0x02
-#define PVC_STATE_FECN 0x08 /* FECN condition */
-#define PVC_STATE_BECN 0x10 /* BECN condition */
-
-
-#define FR_UI 0x03
-#define FR_PAD 0x00
-
-#define NLPID_IP 0xCC
-#define NLPID_IPV6 0x8E
-#define NLPID_SNAP 0x80
-#define NLPID_PAD 0x00
-#define NLPID_Q933 0x08
-
-
-#define LMI_DLCI 0 /* LMI DLCI */
-#define LMI_PROTO 0x08
-#define LMI_CALLREF 0x00 /* Call Reference */
-#define LMI_ANSI_LOCKSHIFT 0x95 /* ANSI lockshift */
-#define LMI_REPTYPE 1 /* report type */
-#define LMI_CCITT_REPTYPE 0x51
-#define LMI_ALIVE 3 /* keep alive */
-#define LMI_CCITT_ALIVE 0x53
-#define LMI_PVCSTAT 7 /* pvc status */
-#define LMI_CCITT_PVCSTAT 0x57
-#define LMI_FULLREP 0 /* full report */
-#define LMI_INTEGRITY 1 /* link integrity report */
-#define LMI_SINGLE 2 /* single pvc report */
+#define FR_UI 0x03
+#define FR_PAD 0x00
+
+#define NLPID_IP 0xCC
+#define NLPID_IPV6 0x8E
+#define NLPID_SNAP 0x80
+#define NLPID_PAD 0x00
+#define NLPID_CCITT_ANSI_LMI 0x08
+#define NLPID_CISCO_LMI 0x09
+
+
+#define LMI_CCITT_ANSI_DLCI 0 /* LMI DLCI */
+#define LMI_CISCO_DLCI 1023
+
+#define LMI_CALLREF 0x00 /* Call Reference */
+#define LMI_ANSI_LOCKSHIFT 0x95 /* ANSI locking shift */
+#define LMI_ANSI_CISCO_REPTYPE 0x01 /* report type */
+#define LMI_CCITT_REPTYPE 0x51
+#define LMI_ANSI_CISCO_ALIVE 0x03 /* keep alive */
+#define LMI_CCITT_ALIVE 0x53
+#define LMI_ANSI_CISCO_PVCSTAT 0x07 /* PVC status */
+#define LMI_CCITT_PVCSTAT 0x57
+
+#define LMI_FULLREP 0x00 /* full report */
+#define LMI_INTEGRITY 0x01 /* link integrity report */
+#define LMI_SINGLE 0x02 /* single PVC report */
+
#define LMI_STATUS_ENQUIRY 0x75
#define LMI_STATUS 0x7D /* reply */
#define LMI_REPT_LEN 1 /* report type element length */
#define LMI_INTEG_LEN 2 /* link integrity element length */
-#define LMI_LENGTH 13 /* standard LMI frame length */
-#define LMI_ANSI_LENGTH 14
+#define LMI_CCITT_CISCO_LENGTH 13 /* LMI frame lengths */
+#define LMI_ANSI_LENGTH 14
typedef struct {
}
-static inline u16 status_to_dlci(u8 *status, int *active, int *new)
-{
- *new = (status[2] & 0x08) ? 1 : 0;
- *active = (status[2] & 0x02) ? 1 : 0;
-
- return ((status[0] & 0x3F) << 4) | ((status[1] & 0x78) >> 3);
-}
-
-
-static inline void dlci_to_status(u16 dlci, u8 *status, int active, int new)
-{
- status[0] = (dlci >> 4) & 0x3F;
- status[1] = ((dlci << 3) & 0x78) | 0x80;
- status[2] = 0x80;
-
- if (new)
- status[2] |= 0x08;
- else if (active)
- status[2] |= 0x02;
-}
-
-
-
static int fr_hard_header(struct sk_buff **skb_p, u16 dlci)
{
u16 head_len;
struct sk_buff *skb = *skb_p;
switch (skb->protocol) {
- case __constant_ntohs(ETH_P_IP):
+ case __constant_ntohs(NLPID_CCITT_ANSI_LMI):
head_len = 4;
skb_push(skb, head_len);
- skb->data[3] = NLPID_IP;
+ skb->data[3] = NLPID_CCITT_ANSI_LMI;
break;
- case __constant_ntohs(ETH_P_IPV6):
+ case __constant_ntohs(NLPID_CISCO_LMI):
head_len = 4;
skb_push(skb, head_len);
- skb->data[3] = NLPID_IPV6;
+ skb->data[3] = NLPID_CISCO_LMI;
break;
- case __constant_ntohs(LMI_PROTO):
+ case __constant_ntohs(ETH_P_IP):
+ head_len = 4;
+ skb_push(skb, head_len);
+ skb->data[3] = NLPID_IP;
+ break;
+
+ case __constant_ntohs(ETH_P_IPV6):
head_len = 4;
skb_push(skb, head_len);
- skb->data[3] = LMI_PROTO;
+ skb->data[3] = NLPID_IPV6;
break;
case __constant_ntohs(ETH_P_802_3):
hdlc_device *hdlc = dev_to_hdlc(dev);
struct sk_buff *skb;
pvc_device *pvc = hdlc->state.fr.first_pvc;
- int len = (hdlc->state.fr.settings.lmi == LMI_ANSI) ? LMI_ANSI_LENGTH
- : LMI_LENGTH;
- int stat_len = 3;
+ int lmi = hdlc->state.fr.settings.lmi;
+ int dce = hdlc->state.fr.settings.dce;
+ int len = lmi == LMI_ANSI ? LMI_ANSI_LENGTH : LMI_CCITT_CISCO_LENGTH;
+ int stat_len = (lmi == LMI_CISCO) ? 6 : 3;
u8 *data;
int i = 0;
- if (hdlc->state.fr.settings.dce && fullrep) {
+ if (dce && fullrep) {
len += hdlc->state.fr.dce_pvc_count * (2 + stat_len);
if (len > HDLC_MAX_MRU) {
printk(KERN_WARNING "%s: Too many PVCs while sending "
}
memset(skb->data, 0, len);
skb_reserve(skb, 4);
- skb->protocol = __constant_htons(LMI_PROTO);
- fr_hard_header(&skb, LMI_DLCI);
+ if (lmi == LMI_CISCO) {
+ skb->protocol = __constant_htons(NLPID_CISCO_LMI);
+ fr_hard_header(&skb, LMI_CISCO_DLCI);
+ } else {
+ skb->protocol = __constant_htons(NLPID_CCITT_ANSI_LMI);
+ fr_hard_header(&skb, LMI_CCITT_ANSI_DLCI);
+ }
data = skb->tail;
data[i++] = LMI_CALLREF;
- data[i++] = hdlc->state.fr.settings.dce
- ? LMI_STATUS : LMI_STATUS_ENQUIRY;
- if (hdlc->state.fr.settings.lmi == LMI_ANSI)
+ data[i++] = dce ? LMI_STATUS : LMI_STATUS_ENQUIRY;
+ if (lmi == LMI_ANSI)
data[i++] = LMI_ANSI_LOCKSHIFT;
- data[i++] = (hdlc->state.fr.settings.lmi == LMI_CCITT)
- ? LMI_CCITT_REPTYPE : LMI_REPTYPE;
+ data[i++] = lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
+ LMI_ANSI_CISCO_REPTYPE;
data[i++] = LMI_REPT_LEN;
data[i++] = fullrep ? LMI_FULLREP : LMI_INTEGRITY;
-
- data[i++] = (hdlc->state.fr.settings.lmi == LMI_CCITT)
- ? LMI_CCITT_ALIVE : LMI_ALIVE;
+ data[i++] = lmi == LMI_CCITT ? LMI_CCITT_ALIVE : LMI_ANSI_CISCO_ALIVE;
data[i++] = LMI_INTEG_LEN;
data[i++] = hdlc->state.fr.txseq =fr_lmi_nextseq(hdlc->state.fr.txseq);
data[i++] = hdlc->state.fr.rxseq;
- if (hdlc->state.fr.settings.dce && fullrep) {
+ if (dce && fullrep) {
while (pvc) {
- data[i++] = (hdlc->state.fr.settings.lmi == LMI_CCITT)
- ? LMI_CCITT_PVCSTAT : LMI_PVCSTAT;
+ data[i++] = lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
+ LMI_ANSI_CISCO_PVCSTAT;
data[i++] = stat_len;
/* LMI start/restart */
fr_log_dlci_active(pvc);
}
- dlci_to_status(pvc->dlci, data + i,
- pvc->state.active, pvc->state.new);
+ if (lmi == LMI_CISCO) {
+ data[i] = pvc->dlci >> 8;
+ data[i + 1] = pvc->dlci & 0xFF;
+ } else {
+ data[i] = (pvc->dlci >> 4) & 0x3F;
+ data[i + 1] = ((pvc->dlci << 3) & 0x78) | 0x80;
+ data[i + 2] = 0x80;
+ }
+
+ if (pvc->state.new)
+ data[i + 2] |= 0x08;
+ else if (pvc->state.active)
+ data[i + 2] |= 0x02;
+
i += stat_len;
pvc = pvc->next;
}
pvc_carrier(0, pvc);
pvc->state.exist = pvc->state.active = 0;
pvc->state.new = 0;
+ if (!hdlc->state.fr.settings.dce)
+ pvc->state.bandwidth = 0;
pvc = pvc->next;
}
}
int i, cnt = 0, reliable;
u32 list;
- if (hdlc->state.fr.settings.dce)
+ if (hdlc->state.fr.settings.dce) {
reliable = hdlc->state.fr.request &&
time_before(jiffies, hdlc->state.fr.last_poll +
hdlc->state.fr.settings.t392 * HZ);
- else {
+ hdlc->state.fr.request = 0;
+ } else {
hdlc->state.fr.last_errors <<= 1; /* Shift the list */
if (hdlc->state.fr.request) {
if (hdlc->state.fr.reliable)
static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
- int stat_len;
pvc_device *pvc;
- int reptype = -1, error, no_ram;
u8 rxseq, txseq;
- int i;
+ int lmi = hdlc->state.fr.settings.lmi;
+ int dce = hdlc->state.fr.settings.dce;
+ int stat_len = (lmi == LMI_CISCO) ? 6 : 3, reptype, error, no_ram, i;
- if (skb->len < ((hdlc->state.fr.settings.lmi == LMI_ANSI)
- ? LMI_ANSI_LENGTH : LMI_LENGTH)) {
+ if (skb->len < (lmi == LMI_ANSI ? LMI_ANSI_LENGTH :
+ LMI_CCITT_CISCO_LENGTH)) {
printk(KERN_INFO "%s: Short LMI frame\n", dev->name);
return 1;
}
- if (skb->data[5] != (!hdlc->state.fr.settings.dce ?
- LMI_STATUS : LMI_STATUS_ENQUIRY)) {
- printk(KERN_INFO "%s: LMI msgtype=%x, Not LMI status %s\n",
- dev->name, skb->data[2],
- hdlc->state.fr.settings.dce ? "enquiry" : "reply");
+ if (skb->data[3] != (lmi == LMI_CISCO ? NLPID_CISCO_LMI :
+ NLPID_CCITT_ANSI_LMI)) {
+ printk(KERN_INFO "%s: Received non-LMI frame with LMI"
+ " DLCI\n", dev->name);
+ return 1;
+ }
+
+ if (skb->data[4] != LMI_CALLREF) {
+ printk(KERN_INFO "%s: Invalid LMI Call reference (0x%02X)\n",
+ dev->name, skb->data[4]);
+ return 1;
+ }
+
+ if (skb->data[5] != (dce ? LMI_STATUS_ENQUIRY : LMI_STATUS)) {
+ printk(KERN_INFO "%s: Invalid LMI Message type (0x%02X)\n",
+ dev->name, skb->data[5]);
return 1;
}
- i = (hdlc->state.fr.settings.lmi == LMI_ANSI) ? 7 : 6;
+ if (lmi == LMI_ANSI) {
+ if (skb->data[6] != LMI_ANSI_LOCKSHIFT) {
+ printk(KERN_INFO "%s: Not ANSI locking shift in LMI"
+ " message (0x%02X)\n", dev->name, skb->data[6]);
+ return 1;
+ }
+ i = 7;
+ } else
+ i = 6;
- if (skb->data[i] !=
- ((hdlc->state.fr.settings.lmi == LMI_CCITT)
- ? LMI_CCITT_REPTYPE : LMI_REPTYPE)) {
- printk(KERN_INFO "%s: Not a report type=%x\n",
+ if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
+ LMI_ANSI_CISCO_REPTYPE)) {
+ printk(KERN_INFO "%s: Not an LMI Report type IE (0x%02X)\n",
dev->name, skb->data[i]);
return 1;
}
- i++;
- i++; /* Skip length field */
+ if (skb->data[++i] != LMI_REPT_LEN) {
+ printk(KERN_INFO "%s: Invalid LMI Report type IE length"
+ " (%u)\n", dev->name, skb->data[i]);
+ return 1;
+ }
- reptype = skb->data[i++];
+ reptype = skb->data[++i];
+ if (reptype != LMI_INTEGRITY && reptype != LMI_FULLREP) {
+ printk(KERN_INFO "%s: Unsupported LMI Report type (0x%02X)\n",
+ dev->name, reptype);
+ return 1;
+ }
- if (skb->data[i]!=
- ((hdlc->state.fr.settings.lmi == LMI_CCITT)
- ? LMI_CCITT_ALIVE : LMI_ALIVE)) {
- printk(KERN_INFO "%s: Unsupported status element=%x\n",
- dev->name, skb->data[i]);
+ if (skb->data[++i] != (lmi == LMI_CCITT ? LMI_CCITT_ALIVE :
+ LMI_ANSI_CISCO_ALIVE)) {
+ printk(KERN_INFO "%s: Not an LMI Link integrity verification"
+ " IE (0x%02X)\n", dev->name, skb->data[i]);
return 1;
}
- i++;
- i++; /* Skip length field */
+ if (skb->data[++i] != LMI_INTEG_LEN) {
+ printk(KERN_INFO "%s: Invalid LMI Link integrity verification"
+ " IE length (%u)\n", dev->name, skb->data[i]);
+ return 1;
+ }
+ i++;
hdlc->state.fr.rxseq = skb->data[i++]; /* TX sequence from peer */
rxseq = skb->data[i++]; /* Should confirm our sequence */
txseq = hdlc->state.fr.txseq;
- if (hdlc->state.fr.settings.dce) {
- if (reptype != LMI_FULLREP && reptype != LMI_INTEGRITY) {
- printk(KERN_INFO "%s: Unsupported report type=%x\n",
- dev->name, reptype);
- return 1;
- }
+ if (dce)
hdlc->state.fr.last_poll = jiffies;
- }
error = 0;
if (!hdlc->state.fr.reliable)
error = 1;
}
- if (hdlc->state.fr.settings.dce) {
+ if (dce) {
if (hdlc->state.fr.fullrep_sent && !error) {
/* Stop sending full report - the last one has been confirmed by DTE */
hdlc->state.fr.fullrep_sent = 0;
hdlc->state.fr.dce_changed = 0;
}
+ hdlc->state.fr.request = 1; /* got request */
fr_lmi_send(dev, reptype == LMI_FULLREP ? 1 : 0);
return 0;
}
if (reptype != LMI_FULLREP)
return 0;
- stat_len = 3;
pvc = hdlc->state.fr.first_pvc;
while (pvc) {
no_ram = 0;
while (skb->len >= i + 2 + stat_len) {
u16 dlci;
+ u32 bw;
unsigned int active, new;
- if (skb->data[i] != ((hdlc->state.fr.settings.lmi == LMI_CCITT)
- ? LMI_CCITT_PVCSTAT : LMI_PVCSTAT)) {
- printk(KERN_WARNING "%s: Invalid PVCSTAT ID: %x\n",
- dev->name, skb->data[i]);
+ if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
+ LMI_ANSI_CISCO_PVCSTAT)) {
+ printk(KERN_INFO "%s: Not an LMI PVC status IE"
+ " (0x%02X)\n", dev->name, skb->data[i]);
return 1;
}
- i++;
- if (skb->data[i] != stat_len) {
- printk(KERN_WARNING "%s: Invalid PVCSTAT length: %x\n",
- dev->name, skb->data[i]);
+ if (skb->data[++i] != stat_len) {
+ printk(KERN_INFO "%s: Invalid LMI PVC status IE length"
+ " (%u)\n", dev->name, skb->data[i]);
return 1;
}
i++;
- dlci = status_to_dlci(skb->data + i, &active, &new);
+ new = !! (skb->data[i + 2] & 0x08);
+ active = !! (skb->data[i + 2] & 0x02);
+ if (lmi == LMI_CISCO) {
+ dlci = (skb->data[i] << 8) | skb->data[i + 1];
+ bw = (skb->data[i + 3] << 16) |
+ (skb->data[i + 4] << 8) |
+ (skb->data[i + 5]);
+ } else {
+ dlci = ((skb->data[i] & 0x3F) << 4) |
+ ((skb->data[i + 1] & 0x78) >> 3);
+ bw = 0;
+ }
pvc = add_pvc(dev, dlci);
pvc->state.deleted = 0;
if (active != pvc->state.active ||
new != pvc->state.new ||
+ bw != pvc->state.bandwidth ||
!pvc->state.exist) {
pvc->state.new = new;
pvc->state.active = active;
+ pvc->state.bandwidth = bw;
pvc_carrier(active, pvc);
fr_log_dlci_active(pvc);
}
pvc_carrier(0, pvc);
pvc->state.active = pvc->state.new = 0;
pvc->state.exist = 0;
+ pvc->state.bandwidth = 0;
fr_log_dlci_active(pvc);
}
pvc = pvc->next;
dlci = q922_to_dlci(skb->data);
- if (dlci == LMI_DLCI) {
- if (hdlc->state.fr.settings.lmi == LMI_NONE)
- goto rx_error; /* LMI packet with no LMI? */
-
- if (data[3] == LMI_PROTO) {
- if (fr_lmi_recv(ndev, skb))
- goto rx_error;
- else {
- dev_kfree_skb_any(skb);
- return NET_RX_SUCCESS;
- }
- }
-
- printk(KERN_INFO "%s: Received non-LMI frame with LMI DLCI\n",
- ndev->name);
- goto rx_error;
+ if ((dlci == LMI_CCITT_ANSI_DLCI &&
+ (hdlc->state.fr.settings.lmi == LMI_ANSI ||
+ hdlc->state.fr.settings.lmi == LMI_CCITT)) ||
+ (dlci == LMI_CISCO_DLCI &&
+ hdlc->state.fr.settings.lmi == LMI_CISCO)) {
+ if (fr_lmi_recv(ndev, skb))
+ goto rx_error;
+ dev_kfree_skb_any(skb);
+ return NET_RX_SUCCESS;
}
pvc = find_pvc(hdlc, dlci);
if ((new_settings.lmi != LMI_NONE &&
new_settings.lmi != LMI_ANSI &&
- new_settings.lmi != LMI_CCITT) ||
+ new_settings.lmi != LMI_CCITT &&
+ new_settings.lmi != LMI_CISCO) ||
new_settings.t391 < 1 ||
new_settings.t392 < 2 ||
new_settings.n391 < 1 ||
git://ftp.safe.ca / safe / jmp / linux-2.6 / commitdiff