aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/net/wan/hdlc_fr.c
blob: e1601d35dceddf133379a57155ca9472294b2eac (plain) (tree)
1
2
3
4
5
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203



                                          
                                                             























                                                                               



                                                





















                              


























                                                                





                                                                        

                                                            






































































































































                                                                      





                                                           
                                                    

                                        
                                                    

                      
                                               

                                        
                                               

                      






                                          

                                        
                                          














































































                                                                              
                                                                        
















































































































                                                                            



                                                                             


                  
                             















                                                                              






                                                                       

                                

                                                          
                                               

                                                          

                                                          
                                                                              



                                                                               
                             
                             

                                                                          















                                                                           













                                                                               











































                                                                         

                                                         













                                                          
                                          


                                                                       

                                           













































                                                                              
                        
                        


                                                                             
 

                                                           



                                                                     















                                                                             


                         








                                                                               
 


                                                                            


                                                
 




                                                                        
 





                                                                              
 



                                                                             

                         
 





                                                                              





                                                                          
                
                                                   









                                                                               
                  




















                                                                       
                                                             













                                                                          









                                              
                       

                                         



                                                                           

                                 
 


                                                                               



                                 











                                                                      














                                                                       
                                                         


                                                           
                                                          














                                                               
                                                 



























                                                              








                                                           




































































































































































































































































































































                                                                             

                                                      































































                                                                              
/*
 * Generic HDLC support routines for Linux
 * Frame Relay support
 *
 * 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
 * as published by the Free Software Foundation.
 *

            Theory of PVC state

 DCE mode:

 (exist,new) -> 0,0 when "PVC create" or if "link unreliable"
         0,x -> 1,1 if "link reliable" when sending FULL STATUS
         1,1 -> 1,0 if received FULL STATUS ACK

 (active)    -> 0 when "ifconfig PVC down" or "link unreliable" or "PVC create"
             -> 1 when "PVC up" and (exist,new) = 1,0

 DTE mode:
 (exist,new,active) = FULL STATUS if "link reliable"
		    = 0, 0, 0 if "link unreliable"
 No LMI:
 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>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/errno.h>
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/pkt_sched.h>
#include <linux/random.h>
#include <linux/inetdevice.h>
#include <linux/lapb.h>
#include <linux/rtnetlink.h>
#include <linux/etherdevice.h>
#include <linux/hdlc.h>

#undef DEBUG_PKT
#undef DEBUG_ECN
#undef DEBUG_LINK

#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_CCITT_CISCO_LENGTH	  13 /* LMI frame lengths */
#define LMI_ANSI_LENGTH		  14


typedef struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned ea1:	1;
	unsigned cr:	1;
	unsigned dlcih:	6;
  
	unsigned ea2:	1;
	unsigned de:	1;
	unsigned becn:	1;
	unsigned fecn:	1;
	unsigned dlcil:	4;
#else
	unsigned dlcih:	6;
	unsigned cr:	1;
	unsigned ea1:	1;

	unsigned dlcil:	4;
	unsigned fecn:	1;
	unsigned becn:	1;
	unsigned de:	1;
	unsigned ea2:	1;
#endif
}__attribute__ ((packed)) fr_hdr;


static inline u16 q922_to_dlci(u8 *hdr)
{
	return ((hdr[0] & 0xFC) << 2) | ((hdr[1] & 0xF0) >> 4);
}



static inline void dlci_to_q922(u8 *hdr, u16 dlci)
{
	hdr[0] = (dlci >> 2) & 0xFC;
	hdr[1] = ((dlci << 4) & 0xF0) | 0x01;
}



static inline pvc_device* find_pvc(hdlc_device *hdlc, u16 dlci)
{
	pvc_device *pvc = hdlc->state.fr.first_pvc;

	while (pvc) {
		if (pvc->dlci == dlci)
			return pvc;
		if (pvc->dlci > dlci)
			return NULL; /* the listed is sorted */
		pvc = pvc->next;
	}

	return NULL;
}


static inline pvc_device* add_pvc(struct net_device *dev, u16 dlci)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	pvc_device *pvc, **pvc_p = &hdlc->state.fr.first_pvc;

	while (*pvc_p) {
		if ((*pvc_p)->dlci == dlci)
			return *pvc_p;
		if ((*pvc_p)->dlci > dlci)
			break;	/* the list is sorted */
		pvc_p = &(*pvc_p)->next;
	}

	pvc = kmalloc(sizeof(pvc_device), GFP_ATOMIC);
	if (!pvc)
		return NULL;

	memset(pvc, 0, sizeof(pvc_device));
	pvc->dlci = dlci;
	pvc->master = dev;
	pvc->next = *pvc_p;	/* Put it in the chain */
	*pvc_p = pvc;
	return pvc;
}


static inline int pvc_is_used(pvc_device *pvc)
{
	return pvc->main != NULL || pvc->ether != NULL;
}


static inline void pvc_carrier(int on, pvc_device *pvc)
{
	if (on) {
		if (pvc->main)
			if (!netif_carrier_ok(pvc->main))
				netif_carrier_on(pvc->main);
		if (pvc->ether)
			if (!netif_carrier_ok(pvc->ether))
				netif_carrier_on(pvc->ether);
	} else {
		if (pvc->main)
			if (netif_carrier_ok(pvc->main))
				netif_carrier_off(pvc->main);
		if (pvc->ether)
			if (netif_carrier_ok(pvc->ether))
				netif_carrier_off(pvc->ether);
	}
}


static inline void delete_unused_pvcs(hdlc_device *hdlc)
{
	pvc_device **pvc_p = &hdlc->state.fr.first_pvc;

	while (*pvc_p) {
		if (!pvc_is_used(*pvc_p)) {
			pvc_device *pvc = *pvc_p;
			*pvc_p = pvc->next;
			kfree(pvc);
			continue;
		}
		pvc_p = &(*pvc_p)->next;
	}
}


static inline struct net_device** get_dev_p(pvc_device *pvc, int type)
{
	if (type == ARPHRD_ETHER)
		return &pvc->ether;
	else
		return &pvc->main;
}


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(NLPID_CCITT_ANSI_LMI):
		head_len = 4;
		skb_push(skb, head_len);
		skb->data[3] = NLPID_CCITT_ANSI_LMI;
		break;

	case __constant_ntohs(NLPID_CISCO_LMI):
		head_len = 4;
		skb_push(skb, head_len);
		skb->data[3] = NLPID_CISCO_LMI;
		break;

	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] = NLPID_IPV6;
		break;

	case __constant_ntohs(ETH_P_802_3):
		head_len = 10;
		if (skb_headroom(skb) < head_len) {
			struct sk_buff *skb2 = skb_realloc_headroom(skb,
								    head_len);
			if (!skb2)
				return -ENOBUFS;
			dev_kfree_skb(skb);
			skb = *skb_p = skb2;
		}
		skb_push(skb, head_len);
		skb->data[3] = FR_PAD;
		skb->data[4] = NLPID_SNAP;
		skb->data[5] = FR_PAD;
		skb->data[6] = 0x80;
		skb->data[7] = 0xC2;
		skb->data[8] = 0x00;
		skb->data[9] = 0x07; /* bridged Ethernet frame w/out FCS */
		break;

	default:
		head_len = 10;
		skb_push(skb, head_len);
		skb->data[3] = FR_PAD;
		skb->data[4] = NLPID_SNAP;
		skb->data[5] = FR_PAD;
		skb->data[6] = FR_PAD;
		skb->data[7] = FR_PAD;
		*(u16*)(skb->data + 8) = skb->protocol;
	}

	dlci_to_q922(skb->data, dlci);
	skb->data[2] = FR_UI;
	return 0;
}



static int pvc_open(struct net_device *dev)
{
	pvc_device *pvc = dev_to_pvc(dev);

	if ((pvc->master->flags & IFF_UP) == 0)
		return -EIO;  /* Master must be UP in order to activate PVC */

	if (pvc->open_count++ == 0) {
		hdlc_device *hdlc = dev_to_hdlc(pvc->master);
		if (hdlc->state.fr.settings.lmi == LMI_NONE)
			pvc->state.active = hdlc->carrier;

		pvc_carrier(pvc->state.active, pvc);
		hdlc->state.fr.dce_changed = 1;
	}
	return 0;
}



static int pvc_close(struct net_device *dev)
{
	pvc_device *pvc = dev_to_pvc(dev);

	if (--pvc->open_count == 0) {
		hdlc_device *hdlc = dev_to_hdlc(pvc->master);
		if (hdlc->state.fr.settings.lmi == LMI_NONE)
			pvc->state.active = 0;

		if (hdlc->state.fr.settings.dce) {
			hdlc->state.fr.dce_changed = 1;
			pvc->state.active = 0;
		}
	}
	return 0;
}



static int pvc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	pvc_device *pvc = dev_to_pvc(dev);
	fr_proto_pvc_info info;

	if (ifr->ifr_settings.type == IF_GET_PROTO) {
		if (dev->type == ARPHRD_ETHER)
			ifr->ifr_settings.type = IF_PROTO_FR_ETH_PVC;
		else
			ifr->ifr_settings.type = IF_PROTO_FR_PVC;

		if (ifr->ifr_settings.size < sizeof(info)) {
			/* data size wanted */
			ifr->ifr_settings.size = sizeof(info);
			return -ENOBUFS;
		}

		info.dlci = pvc->dlci;
		memcpy(info.master, pvc->master->name, IFNAMSIZ);
		if (copy_to_user(ifr->ifr_settings.ifs_ifsu.fr_pvc_info,
				 &info, sizeof(info)))
			return -EFAULT;
		return 0;
	}

	return -EINVAL;
}


static inline struct net_device_stats *pvc_get_stats(struct net_device *dev)
{
	return netdev_priv(dev);
}



static int pvc_xmit(struct sk_buff *skb, struct net_device *dev)
{
	pvc_device *pvc = dev_to_pvc(dev);
	struct net_device_stats *stats = pvc_get_stats(dev);

	if (pvc->state.active) {
		if (dev->type == ARPHRD_ETHER) {
			int pad = ETH_ZLEN - skb->len;
			if (pad > 0) { /* Pad the frame with zeros */
				int len = skb->len;
				if (skb_tailroom(skb) < pad)
					if (pskb_expand_head(skb, 0, pad,
							     GFP_ATOMIC)) {
						stats->tx_dropped++;
						dev_kfree_skb(skb);
						return 0;
					}
				skb_put(skb, pad);
				memset(skb->data + len, 0, pad);
			}
			skb->protocol = __constant_htons(ETH_P_802_3);
		}
		if (!fr_hard_header(&skb, pvc->dlci)) {
			stats->tx_bytes += skb->len;
			stats->tx_packets++;
			if (pvc->state.fecn) /* TX Congestion counter */
				stats->tx_compressed++;
			skb->dev = pvc->master;
			dev_queue_xmit(skb);
			return 0;
		}
	}

	stats->tx_dropped++;
	dev_kfree_skb(skb);
	return 0;
}



static int pvc_change_mtu(struct net_device *dev, int new_mtu)
{
	if ((new_mtu < 68) || (new_mtu > HDLC_MAX_MTU))
		return -EINVAL;
	dev->mtu = new_mtu;
	return 0;
}



static inline void fr_log_dlci_active(pvc_device *pvc)
{
	printk(KERN_INFO "%s: DLCI %d [%s%s%s]%s %s\n",
	       pvc->master->name,
	       pvc->dlci,
	       pvc->main ? pvc->main->name : "",
	       pvc->main && pvc->ether ? " " : "",
	       pvc->ether ? pvc->ether->name : "",
	       pvc->state.new ? " new" : "",
	       !pvc->state.exist ? "deleted" :
	       pvc->state.active ? "active" : "inactive");
}



static inline u8 fr_lmi_nextseq(u8 x)
{
	x++;
	return x ? x : 1;
}



static void fr_lmi_send(struct net_device *dev, int fullrep)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	struct sk_buff *skb;
	pvc_device *pvc = hdlc->state.fr.first_pvc;
	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 (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 "
			       "LMI full report\n", dev->name);
			return;
		}
	}

	skb = dev_alloc_skb(len);
	if (!skb) {
		printk(KERN_WARNING "%s: Memory squeeze on fr_lmi_send()\n",
		       dev->name);
		return;
	}
	memset(skb->data, 0, len);
	skb_reserve(skb, 4);
	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++] = dce ? LMI_STATUS : LMI_STATUS_ENQUIRY;
	if (lmi == LMI_ANSI)
		data[i++] = LMI_ANSI_LOCKSHIFT;
	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++] = 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 (dce && fullrep) {
		while (pvc) {
			data[i++] = lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
				LMI_ANSI_CISCO_PVCSTAT;
			data[i++] = stat_len;

			/* LMI start/restart */
			if (hdlc->state.fr.reliable && !pvc->state.exist) {
				pvc->state.exist = pvc->state.new = 1;
				fr_log_dlci_active(pvc);
			}

			/* ifconfig PVC up */
			if (pvc->open_count && !pvc->state.active &&
			    pvc->state.exist && !pvc->state.new) {
				pvc_carrier(1, pvc);
				pvc->state.active = 1;
				fr_log_dlci_active(pvc);
			}

			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;
		}
	}

	skb_put(skb, i);
	skb->priority = TC_PRIO_CONTROL;
	skb->dev = dev;
	skb->nh.raw = skb->data;

	dev_queue_xmit(skb);
}



static void fr_set_link_state(int reliable, struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	pvc_device *pvc = hdlc->state.fr.first_pvc;

	hdlc->state.fr.reliable = reliable;
	if (reliable) {
		if (!netif_carrier_ok(dev))
			netif_carrier_on(dev);

		hdlc->state.fr.n391cnt = 0; /* Request full status */
		hdlc->state.fr.dce_changed = 1;

		if (hdlc->state.fr.settings.lmi == LMI_NONE) {
			while (pvc) {	/* Activate all PVCs */
				pvc_carrier(1, pvc);
				pvc->state.exist = pvc->state.active = 1;
				pvc->state.new = 0;
				pvc = pvc->next;
			}
		}
	} else {
		if (netif_carrier_ok(dev))
			netif_carrier_off(dev);

		while (pvc) {		/* Deactivate all PVCs */
			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;
		}
	}
}



static void fr_timer(unsigned long arg)
{
	struct net_device *dev = (struct net_device *)arg;
	hdlc_device *hdlc = dev_to_hdlc(dev);
	int i, cnt = 0, reliable;
	u32 list;

	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);
		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)
				printk(KERN_INFO "%s: No LMI status reply "
				       "received\n", dev->name);
			hdlc->state.fr.last_errors |= 1;
		}

		list = hdlc->state.fr.last_errors;
		for (i = 0; i < hdlc->state.fr.settings.n393; i++, list >>= 1)
			cnt += (list & 1);	/* errors count */

		reliable = (cnt < hdlc->state.fr.settings.n392);
	}

	if (hdlc->state.fr.reliable != reliable) {
		printk(KERN_INFO "%s: Link %sreliable\n", dev->name,
		       reliable ? "" : "un");
		fr_set_link_state(reliable, dev);
	}

	if (hdlc->state.fr.settings.dce)
		hdlc->state.fr.timer.expires = jiffies +
			hdlc->state.fr.settings.t392 * HZ;
	else {
		if (hdlc->state.fr.n391cnt)
			hdlc->state.fr.n391cnt--;

		fr_lmi_send(dev, hdlc->state.fr.n391cnt == 0);

		hdlc->state.fr.last_poll = jiffies;
		hdlc->state.fr.request = 1;
		hdlc->state.fr.timer.expires = jiffies +
			hdlc->state.fr.settings.t391 * HZ;
	}

	hdlc->state.fr.timer.function = fr_timer;
	hdlc->state.fr.timer.data = arg;
	add_timer(&hdlc->state.fr.timer);
}



static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	pvc_device *pvc;
	u8 rxseq, txseq;
	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 < (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[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;
	}

	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] != (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;
	}

	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];
	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] != (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;
	}

	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 (dce)
		hdlc->state.fr.last_poll = jiffies;

	error = 0;
	if (!hdlc->state.fr.reliable)
		error = 1;

	if (rxseq == 0 || rxseq != txseq) {
		hdlc->state.fr.n391cnt = 0; /* Ask for full report next time */
		error = 1;
	}

	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;
			pvc = hdlc->state.fr.first_pvc;
			while (pvc) {
				if (pvc->state.new) {
					pvc->state.new = 0;

/* Tell DTE that new PVC is now active */
					hdlc->state.fr.dce_changed = 1;
				}
				pvc = pvc->next;
			}
		}

		if (hdlc->state.fr.dce_changed) {
			reptype = LMI_FULLREP;
			hdlc->state.fr.fullrep_sent = 1;
			hdlc->state.fr.dce_changed = 0;
		}

		hdlc->state.fr.request = 1; /* got request */
		fr_lmi_send(dev, reptype == LMI_FULLREP ? 1 : 0);
		return 0;
	}

	/* DTE */

	hdlc->state.fr.request = 0; /* got response, no request pending */

	if (error)
		return 0;

	if (reptype != LMI_FULLREP)
		return 0;

	pvc = hdlc->state.fr.first_pvc;

	while (pvc) {
		pvc->state.deleted = 1;
		pvc = pvc->next;
	}

	no_ram = 0;
	while (skb->len >= i + 2 + stat_len) {
		u16 dlci;
		u32 bw;
		unsigned int active, new;

		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;
		}

		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++;

		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);

		if (!pvc && !no_ram) {
			printk(KERN_WARNING
			       "%s: Memory squeeze on fr_lmi_recv()\n",
			       dev->name);
			no_ram = 1;
		}

		if (pvc) {
			pvc->state.exist = 1;
			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);
			}
		}

		i += stat_len;
	}

	pvc = hdlc->state.fr.first_pvc;

	while (pvc) {
		if (pvc->state.deleted && pvc->state.exist) {
			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;
	}

	/* Next full report after N391 polls */
	hdlc->state.fr.n391cnt = hdlc->state.fr.settings.n391;

	return 0;
}



static int fr_rx(struct sk_buff *skb)
{
	struct net_device *ndev = skb->dev;
	hdlc_device *hdlc = dev_to_hdlc(ndev);
	fr_hdr *fh = (fr_hdr*)skb->data;
	u8 *data = skb->data;
	u16 dlci;
	pvc_device *pvc;
	struct net_device *dev = NULL;

	if (skb->len <= 4 || fh->ea1 || data[2] != FR_UI)
		goto rx_error;

	dlci = q922_to_dlci(skb->data);

	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 (!pvc) {
#ifdef DEBUG_PKT
		printk(KERN_INFO "%s: No PVC for received frame's DLCI %d\n",
		       ndev->name, dlci);
#endif
		dev_kfree_skb_any(skb);
		return NET_RX_DROP;
	}

	if (pvc->state.fecn != fh->fecn) {
#ifdef DEBUG_ECN
		printk(KERN_DEBUG "%s: DLCI %d FECN O%s\n", ndev->name,
		       dlci, fh->fecn ? "N" : "FF");
#endif
		pvc->state.fecn ^= 1;
	}

	if (pvc->state.becn != fh->becn) {
#ifdef DEBUG_ECN
		printk(KERN_DEBUG "%s: DLCI %d BECN O%s\n", ndev->name,
		       dlci, fh->becn ? "N" : "FF");
#endif
		pvc->state.becn ^= 1;
	}


	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
		hdlc->stats.rx_dropped++;
		return NET_RX_DROP;
	}

	if (data[3] == NLPID_IP) {
		skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
		dev = pvc->main;
		skb->protocol = htons(ETH_P_IP);

	} else if (data[3] == NLPID_IPV6) {
		skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
		dev = pvc->main;
		skb->protocol = htons(ETH_P_IPV6);

	} else if (skb->len > 10 && data[3] == FR_PAD &&
		   data[4] == NLPID_SNAP && data[5] == FR_PAD) {
		u16 oui = ntohs(*(u16*)(data + 6));
		u16 pid = ntohs(*(u16*)(data + 8));
		skb_pull(skb, 10);

		switch ((((u32)oui) << 16) | pid) {
		case ETH_P_ARP: /* routed frame with SNAP */
		case ETH_P_IPX:
		case ETH_P_IP:	/* a long variant */
		case ETH_P_IPV6:
			dev = pvc->main;
			skb->protocol = htons(pid);
			break;

		case 0x80C20007: /* bridged Ethernet frame */
			if ((dev = pvc->ether) != NULL)
				skb->protocol = eth_type_trans(skb, dev);
			break;

		default:
			printk(KERN_INFO "%s: Unsupported protocol, OUI=%x "
			       "PID=%x\n", ndev->name, oui, pid);
			dev_kfree_skb_any(skb);
			return NET_RX_DROP;
		}
	} else {
		printk(KERN_INFO "%s: Unsupported protocol, NLPID=%x "
		       "length = %i\n", ndev->name, data[3], skb->len);
		dev_kfree_skb_any(skb);
		return NET_RX_DROP;
	}

	if (dev) {
		struct net_device_stats *stats = pvc_get_stats(dev);
		stats->rx_packets++; /* PVC traffic */
		stats->rx_bytes += skb->len;
		if (pvc->state.becn)
			stats->rx_compressed++;
		skb->dev = dev;
		netif_rx(skb);
		return NET_RX_SUCCESS;
	} else {
		dev_kfree_skb_any(skb);
		return NET_RX_DROP;
	}

 rx_error:
	hdlc->stats.rx_errors++; /* Mark error */
	dev_kfree_skb_any(skb);
	return NET_RX_DROP;
}



static void fr_start(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
#ifdef DEBUG_LINK
	printk(KERN_DEBUG "fr_start\n");
#endif
	if (hdlc->state.fr.settings.lmi != LMI_NONE) {
		hdlc->state.fr.reliable = 0;
		hdlc->state.fr.dce_changed = 1;
		hdlc->state.fr.request = 0;
		hdlc->state.fr.fullrep_sent = 0;
		hdlc->state.fr.last_errors = 0xFFFFFFFF;
		hdlc->state.fr.n391cnt = 0;
		hdlc->state.fr.txseq = hdlc->state.fr.rxseq = 0;

		init_timer(&hdlc->state.fr.timer);
		/* First poll after 1 s */
		hdlc->state.fr.timer.expires = jiffies + HZ;
		hdlc->state.fr.timer.function = fr_timer;
		hdlc->state.fr.timer.data = (unsigned long)dev;
		add_timer(&hdlc->state.fr.timer);
	} else
		fr_set_link_state(1, dev);
}



static void fr_stop(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
#ifdef DEBUG_LINK
	printk(KERN_DEBUG "fr_stop\n");
#endif
	if (hdlc->state.fr.settings.lmi != LMI_NONE)
		del_timer_sync(&hdlc->state.fr.timer);
	fr_set_link_state(0, dev);
}



static void fr_close(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	pvc_device *pvc = hdlc->state.fr.first_pvc;

	while (pvc) {		/* Shutdown all PVCs for this FRAD */
		if (pvc->main)
			dev_close(pvc->main);
		if (pvc->ether)
			dev_close(pvc->ether);
		pvc = pvc->next;
	}
}

static void dlci_setup(struct net_device *dev)
{
	dev->type = ARPHRD_DLCI;
	dev->flags = IFF_POINTOPOINT;
	dev->hard_header_len = 10;
	dev->addr_len = 2;
}

static int fr_add_pvc(struct net_device *master, unsigned int dlci, int type)
{
	hdlc_device *hdlc = dev_to_hdlc(master);
	pvc_device *pvc = NULL;
	struct net_device *dev;
	int result, used;
	char * prefix = "pvc%d";

	if (type == ARPHRD_ETHER)
		prefix = "pvceth%d";

	if ((pvc = add_pvc(master, dlci)) == NULL) {
		printk(KERN_WARNING "%s: Memory squeeze on fr_add_pvc()\n",
		       master->name);
		return -ENOBUFS;
	}

	if (*get_dev_p(pvc, type))
		return -EEXIST;

	used = pvc_is_used(pvc);

	if (type == ARPHRD_ETHER)
		dev = alloc_netdev(sizeof(struct net_device_stats),
				   "pvceth%d", ether_setup);
	else
		dev = alloc_netdev(sizeof(struct net_device_stats),
				   "pvc%d", dlci_setup);

	if (!dev) {
		printk(KERN_WARNING "%s: Memory squeeze on fr_pvc()\n",
		       master->name);
		delete_unused_pvcs(hdlc);
		return -ENOBUFS;
	}

	if (type == ARPHRD_ETHER) {
		memcpy(dev->dev_addr, "\x00\x01", 2);
                get_random_bytes(dev->dev_addr + 2, ETH_ALEN - 2);
	} else {
		*(u16*)dev->dev_addr = htons(dlci);
		dlci_to_q922(dev->broadcast, dlci);
	}
	dev->hard_start_xmit = pvc_xmit;
	dev->get_stats = pvc_get_stats;
	dev->open = pvc_open;
	dev->stop = pvc_close;
	dev->do_ioctl = pvc_ioctl;
	dev->change_mtu = pvc_change_mtu;
	dev->mtu = HDLC_MAX_MTU;
	dev->tx_queue_len = 0;
	dev->priv = pvc;

	result = dev_alloc_name(dev, dev->name);
	if (result < 0) {
		free_netdev(dev);
		delete_unused_pvcs(hdlc);
		return result;
	}

	if (register_netdevice(dev) != 0) {
		free_netdev(dev);
		delete_unused_pvcs(hdlc);
		return -EIO;
	}

	dev->destructor = free_netdev;
	*get_dev_p(pvc, type) = dev;
	if (!used) {
		hdlc->state.fr.dce_changed = 1;
		hdlc->state.fr.dce_pvc_count++;
	}
	return 0;
}



static int fr_del_pvc(hdlc_device *hdlc, unsigned int dlci, int type)
{
	pvc_device *pvc;
	struct net_device *dev;

	if ((pvc = find_pvc(hdlc, dlci)) == NULL)
		return -ENOENT;

	if ((dev = *get_dev_p(pvc, type)) == NULL)
		return -ENOENT;

	if (dev->flags & IFF_UP)
		return -EBUSY;		/* PVC in use */

	unregister_netdevice(dev); /* the destructor will free_netdev(dev) */
	*get_dev_p(pvc, type) = NULL;

	if (!pvc_is_used(pvc)) {
		hdlc->state.fr.dce_pvc_count--;
		hdlc->state.fr.dce_changed = 1;
	}
	delete_unused_pvcs(hdlc);
	return 0;
}



static void fr_destroy(hdlc_device *hdlc)
{
	pvc_device *pvc;

	pvc = hdlc->state.fr.first_pvc;
	hdlc->state.fr.first_pvc = NULL; /* All PVCs destroyed */
	hdlc->state.fr.dce_pvc_count = 0;
	hdlc->state.fr.dce_changed = 1;

	while (pvc) {
		pvc_device *next = pvc->next;
		/* destructors will free_netdev() main and ether */
		if (pvc->main)
			unregister_netdevice(pvc->main);

		if (pvc->ether)
			unregister_netdevice(pvc->ether);

		kfree(pvc);
		pvc = next;
	}
}



int hdlc_fr_ioctl(struct net_device *dev, struct ifreq *ifr)
{
	fr_proto __user *fr_s = ifr->ifr_settings.ifs_ifsu.fr;
	const size_t size = sizeof(fr_proto);
	fr_proto new_settings;
	hdlc_device *hdlc = dev_to_hdlc(dev);
	fr_proto_pvc pvc;
	int result;

	switch (ifr->ifr_settings.type) {
	case IF_GET_PROTO:
		ifr->ifr_settings.type = IF_PROTO_FR;
		if (ifr->ifr_settings.size < size) {
			ifr->ifr_settings.size = size; /* data size wanted */
			return -ENOBUFS;
		}
		if (copy_to_user(fr_s, &hdlc->state.fr.settings, size))
			return -EFAULT;
		return 0;

	case IF_PROTO_FR:
		if(!capable(CAP_NET_ADMIN))
			return -EPERM;

		if(dev->flags & IFF_UP)
			return -EBUSY;

		if (copy_from_user(&new_settings, fr_s, size))
			return -EFAULT;

		if (new_settings.lmi == LMI_DEFAULT)
			new_settings.lmi = LMI_ANSI;

		if ((new_settings.lmi != LMI_NONE &&
		     new_settings.lmi != LMI_ANSI &&
		     new_settings.lmi != LMI_CCITT &&
		     new_settings.lmi != LMI_CISCO) ||
		    new_settings.t391 < 1 ||
		    new_settings.t392 < 2 ||
		    new_settings.n391 < 1 ||
		    new_settings.n392 < 1 ||
		    new_settings.n393 < new_settings.n392 ||
		    new_settings.n393 > 32 ||
		    (new_settings.dce != 0 &&
		     new_settings.dce != 1))
			return -EINVAL;

		result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
		if (result)
			return result;

		if (hdlc->proto.id != IF_PROTO_FR) {
			hdlc_proto_detach(hdlc);
			hdlc->state.fr.first_pvc = NULL;
			hdlc->state.fr.dce_pvc_count = 0;
		}
		memcpy(&hdlc->state.fr.settings, &new_settings, size);
		memset(&hdlc->proto, 0, sizeof(hdlc->proto));

		hdlc->proto.close = fr_close;
		hdlc->proto.start = fr_start;
		hdlc->proto.stop = fr_stop;
		hdlc->proto.detach = fr_destroy;
		hdlc->proto.netif_rx = fr_rx;
		hdlc->proto.id = IF_PROTO_FR;
		dev->hard_start_xmit = hdlc->xmit;
		dev->hard_header = NULL;
		dev->type = ARPHRD_FRAD;
		dev->flags = IFF_POINTOPOINT | IFF_NOARP;
		dev->addr_len = 0;
		return 0;

	case IF_PROTO_FR_ADD_PVC:
	case IF_PROTO_FR_DEL_PVC:
	case IF_PROTO_FR_ADD_ETH_PVC:
	case IF_PROTO_FR_DEL_ETH_PVC:
		if(!capable(CAP_NET_ADMIN))
			return -EPERM;

		if (copy_from_user(&pvc, ifr->ifr_settings.ifs_ifsu.fr_pvc,
				   sizeof(fr_proto_pvc)))
			return -EFAULT;

		if (pvc.dlci <= 0 || pvc.dlci >= 1024)
			return -EINVAL;	/* Only 10 bits, DLCI 0 reserved */

		if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC ||
		    ifr->ifr_settings.type == IF_PROTO_FR_DEL_ETH_PVC)
			result = ARPHRD_ETHER; /* bridged Ethernet device */
		else
			result = ARPHRD_DLCI;

		if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_PVC ||
		    ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC)
			return fr_add_pvc(dev, pvc.dlci, result);
		else
			return fr_del_pvc(hdlc, pvc.dlci, result);
	}

	return -EINVAL;
}