WAN: new synchronous PPP implementation for generic HDLC.
authorKrzysztof Hałasa <khc@pm.waw.pl>
Thu, 14 Aug 2008 17:17:38 +0000 (19:17 +0200)
committerKrzysztof Hałasa <khc@pm.waw.pl>
Sat, 22 Nov 2008 01:49:48 +0000 (02:49 +0100)
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
Documentation/networking/generic-hdlc.txt
drivers/net/wan/Makefile
drivers/net/wan/hdlc_ppp.c

index 31bc8b7..4eb3cc4 100644 (file)
@@ -3,15 +3,15 @@ Krzysztof Halasa <khc@pm.waw.pl>
 
 
 Generic HDLC layer currently supports:
-1. Frame Relay (ANSI, CCITT, Cisco and no LMI).
+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).
+2. raw HDLC - either IP (IPv4) interface or Ethernet device emulation
+3. Cisco HDLC
+4. PPP
 5. X.25 (uses X.25 routines).
 
 Generic HDLC is a protocol driver only - it needs a low-level driver
index 1025496..cec1681 100644 (file)
@@ -14,7 +14,7 @@ obj-$(CONFIG_HDLC_RAW)                += hdlc_raw.o
 obj-$(CONFIG_HDLC_RAW_ETH)     += hdlc_raw_eth.o
 obj-$(CONFIG_HDLC_CISCO)       += hdlc_cisco.o
 obj-$(CONFIG_HDLC_FR)          += hdlc_fr.o
-obj-$(CONFIG_HDLC_PPP)         += hdlc_ppp.o   syncppp.o
+obj-$(CONFIG_HDLC_PPP)         += hdlc_ppp.o
 obj-$(CONFIG_HDLC_X25)         += hdlc_x25.o
 
 pc300-y                                := pc300_drv.o
index 4efe9e6..72fae21 100644 (file)
@@ -2,7 +2,7 @@
  * Generic HDLC support routines for Linux
  * Point-to-point protocol support
  *
- * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 1999 - 2008 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
 #include <linux/module.h>
 #include <linux/pkt_sched.h>
 #include <linux/poll.h>
-#include <linux/rtnetlink.h>
 #include <linux/skbuff.h>
 #include <linux/slab.h>
-#include <net/syncppp.h>
+#include <linux/spinlock.h>
+
+#define DEBUG_CP               0 /* also bytes# to dump */
+#define DEBUG_STATE            0
+#define DEBUG_HARD_HEADER      0
+
+#define HDLC_ADDR_ALLSTATIONS  0xFF
+#define HDLC_CTRL_UI           0x03
+
+#define PID_LCP                        0xC021
+#define PID_IP                 0x0021
+#define PID_IPCP               0x8021
+#define PID_IPV6               0x0057
+#define PID_IPV6CP             0x8057
+
+enum {IDX_LCP = 0, IDX_IPCP, IDX_IPV6CP, IDX_COUNT};
+enum {CP_CONF_REQ = 1, CP_CONF_ACK, CP_CONF_NAK, CP_CONF_REJ, CP_TERM_REQ,
+      CP_TERM_ACK, CP_CODE_REJ, LCP_PROTO_REJ, LCP_ECHO_REQ, LCP_ECHO_REPLY,
+      LCP_DISC_REQ, CP_CODES};
+#if DEBUG_CP
+static const char *const code_names[CP_CODES] = {
+       "0", "ConfReq", "ConfAck", "ConfNak", "ConfRej", "TermReq",
+       "TermAck", "CodeRej", "ProtoRej", "EchoReq", "EchoReply", "Discard"
+};
+static char debug_buffer[64 + 3 * DEBUG_CP];
+#endif
+
+enum {LCP_OPTION_MRU = 1, LCP_OPTION_ACCM, LCP_OPTION_MAGIC = 5};
+
+struct hdlc_header {
+       u8 address;
+       u8 control;
+       __be16 protocol;
+};
+
+struct cp_header {
+       u8 code;
+       u8 id;
+       __be16 len;
+};
+
 
-struct ppp_state {
-       struct ppp_device pppdev;
-       struct ppp_device *syncppp_ptr;
-       int (*old_change_mtu)(struct net_device *dev, int new_mtu);
+struct proto {
+       struct net_device *dev;
+       struct timer_list timer;
+       unsigned long timeout;
+       u16 pid;                /* protocol ID */
+       u8 state;
+       u8 cr_id;               /* ID of last Configuration-Request */
+       u8 restart_counter;
 };
 
+struct ppp {
+       struct proto protos[IDX_COUNT];
+       spinlock_t lock;
+       unsigned long last_pong;
+       unsigned int req_timeout, cr_retries, term_retries;
+       unsigned int keepalive_interval, keepalive_timeout;
+       u8 seq;                 /* local sequence number for requests */
+       u8 echo_id;             /* ID of last Echo-Request (LCP) */
+};
+
+enum {CLOSED = 0, STOPPED, STOPPING, REQ_SENT, ACK_RECV, ACK_SENT, OPENED,
+      STATES, STATE_MASK = 0xF};
+enum {START = 0, STOP, TO_GOOD, TO_BAD, RCR_GOOD, RCR_BAD, RCA, RCN, RTR, RTA,
+      RUC, RXJ_GOOD, RXJ_BAD, EVENTS};
+enum {INV = 0x10, IRC = 0x20, ZRC = 0x40, SCR = 0x80, SCA = 0x100,
+      SCN = 0x200, STR = 0x400, STA = 0x800, SCJ = 0x1000};
+
+#if DEBUG_STATE
+static const char *const state_names[STATES] = {
+       "Closed", "Stopped", "Stopping", "ReqSent", "AckRecv", "AckSent",
+       "Opened"
+};
+static const char *const event_names[EVENTS] = {
+       "Start", "Stop", "TO+", "TO-", "RCR+", "RCR-", "RCA", "RCN",
+       "RTR", "RTA", "RUC", "RXJ+", "RXJ-"
+};
+#endif
+
+static struct sk_buff_head tx_queue; /* used when holding the spin lock */
+
 static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr);
 
+static inline struct ppp* get_ppp(struct net_device *dev)
+{
+       return (struct ppp *)dev_to_hdlc(dev)->state;
+}
 
-static inline struct ppp_state* state(hdlc_device *hdlc)
+static inline struct proto* get_proto(struct net_device *dev, u16 pid)
 {
-       return(struct ppp_state *)(hdlc->state);
+       struct ppp *ppp = get_ppp(dev);
+
+       switch (pid) {
+       case PID_LCP:
+               return &ppp->protos[IDX_LCP];
+       case PID_IPCP:
+               return &ppp->protos[IDX_IPCP];
+       case PID_IPV6CP:
+               return &ppp->protos[IDX_IPV6CP];
+       default:
+               return NULL;
+       }
 }
 
+static inline const char* proto_name(u16 pid)
+{
+       switch (pid) {
+       case PID_LCP:
+               return "LCP";
+       case PID_IPCP:
+               return "IPCP";
+       case PID_IPV6CP:
+               return "IPV6CP";
+       default:
+               return NULL;
+       }
+}
 
-static int ppp_open(struct net_device *dev)
+static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev)
 {
-       hdlc_device *hdlc = dev_to_hdlc(dev);
-       int (*old_ioctl)(struct net_device *, struct ifreq *, int);
-       int result;
+       struct hdlc_header *data = (struct hdlc_header*)skb->data;
+
+       if (skb->len < sizeof(struct hdlc_header))
+               return htons(ETH_P_HDLC);
+       if (data->address != HDLC_ADDR_ALLSTATIONS ||
+           data->control != HDLC_CTRL_UI)
+               return htons(ETH_P_HDLC);
+
+       switch (data->protocol) {
+       case __constant_htons(PID_IP):
+               skb_pull(skb, sizeof(struct hdlc_header));
+               return htons(ETH_P_IP);
 
-       dev->ml_priv = &state(hdlc)->syncppp_ptr;
-       state(hdlc)->syncppp_ptr = &state(hdlc)->pppdev;
-       state(hdlc)->pppdev.dev = dev;
+       case __constant_htons(PID_IPV6):
+               skb_pull(skb, sizeof(struct hdlc_header));
+               return htons(ETH_P_IPV6);
 
-       old_ioctl = dev->do_ioctl;
-       state(hdlc)->old_change_mtu = dev->change_mtu;
-       sppp_attach(&state(hdlc)->pppdev);
-       /* sppp_attach nukes them. We don't need syncppp's ioctl */
-       dev->do_ioctl = old_ioctl;
-       state(hdlc)->pppdev.sppp.pp_flags &= ~PP_CISCO;
-       dev->type = ARPHRD_PPP;
-       result = sppp_open(dev);
-       if (result) {
-               sppp_detach(dev);
-               return result;
+       default:
+               return htons(ETH_P_HDLC);
        }
+}
 
-       return 0;
+
+static int ppp_hard_header(struct sk_buff *skb, struct net_device *dev,
+                          u16 type, const void *daddr, const void *saddr,
+                          unsigned int len)
+{
+       struct hdlc_header *data;
+#if DEBUG_HARD_HEADER
+       printk(KERN_DEBUG "%s: ppp_hard_header() called\n", dev->name);
+#endif
+
+       skb_push(skb, sizeof(struct hdlc_header));
+       data = (struct hdlc_header*)skb->data;
+
+       data->address = HDLC_ADDR_ALLSTATIONS;
+       data->control = HDLC_CTRL_UI;
+       switch (type) {
+       case ETH_P_IP:
+               data->protocol = htons(PID_IP);
+               break;
+       case ETH_P_IPV6:
+               data->protocol = htons(PID_IPV6);
+               break;
+       case PID_LCP:
+       case PID_IPCP:
+       case PID_IPV6CP:
+               data->protocol = htons(type);
+               break;
+       default:                /* unknown protocol */
+               data->protocol = 0;
+       }
+       return sizeof(struct hdlc_header);
 }
 
 
+static void ppp_tx_flush(void)
+{
+       struct sk_buff *skb;
+       while ((skb = skb_dequeue(&tx_queue)) != NULL)
+               dev_queue_xmit(skb);
+}
 
-static void ppp_close(struct net_device *dev)
+static void ppp_tx_cp(struct net_device *dev, u16 pid, u8 code,
+                     u8 id, unsigned int len, const void *data)
 {
-       hdlc_device *hdlc = dev_to_hdlc(dev);
+       struct sk_buff *skb;
+       struct cp_header *cp;
+       unsigned int magic_len = 0;
+       static u32 magic;
+
+#if DEBUG_CP
+       int i;
+       char *ptr;
+#endif
+
+       if (pid == PID_LCP && (code == LCP_ECHO_REQ || code == LCP_ECHO_REPLY))
+               magic_len = sizeof(magic);
+
+       skb = dev_alloc_skb(sizeof(struct hdlc_header) +
+                           sizeof(struct cp_header) + magic_len + len);
+       if (!skb) {
+               printk(KERN_WARNING "%s: out of memory in ppp_tx_cp()\n",
+                      dev->name);
+               return;
+       }
+       skb_reserve(skb, sizeof(struct hdlc_header));
+
+       cp = (struct cp_header *)skb_put(skb, sizeof(struct cp_header));
+       cp->code = code;
+       cp->id = id;
+       cp->len = htons(sizeof(struct cp_header) + magic_len + len);
+
+       if (magic_len)
+               memcpy(skb_put(skb, magic_len), &magic, magic_len);
+       if (len)
+               memcpy(skb_put(skb, len), data, len);
+
+#if DEBUG_CP
+       BUG_ON(code >= CP_CODES);
+       ptr = debug_buffer;
+       *ptr = '\x0';
+       for (i = 0; i < min_t(unsigned int, magic_len + len, DEBUG_CP); i++) {
+               sprintf(ptr, " %02X", skb->data[sizeof(struct cp_header) + i]);
+               ptr += strlen(ptr);
+       }
+       printk(KERN_DEBUG "%s: TX %s [%s id 0x%X]%s\n", dev->name,
+              proto_name(pid), code_names[code], id, debug_buffer);
+#endif
 
-       sppp_close(dev);
-       sppp_detach(dev);
+       ppp_hard_header(skb, dev, pid, NULL, NULL, 0);
 
-       dev->change_mtu = state(hdlc)->old_change_mtu;
-       dev->mtu = HDLC_MAX_MTU;
-       dev->hard_header_len = 16;
+       skb->priority = TC_PRIO_CONTROL;
+       skb->dev = dev;
+       skb_reset_network_header(skb);
+       skb_queue_tail(&tx_queue, skb);
 }
 
 
+/* State transition table (compare STD-51)
+   Events                                   Actions
+   TO+  = Timeout with counter > 0          irc = Initialize-Restart-Count
+   TO-  = Timeout with counter expired      zrc = Zero-Restart-Count
+
+   RCR+ = Receive-Configure-Request (Good)  scr = Send-Configure-Request
+   RCR- = Receive-Configure-Request (Bad)
+   RCA  = Receive-Configure-Ack             sca = Send-Configure-Ack
+   RCN  = Receive-Configure-Nak/Rej         scn = Send-Configure-Nak/Rej
+
+   RTR  = Receive-Terminate-Request         str = Send-Terminate-Request
+   RTA  = Receive-Terminate-Ack             sta = Send-Terminate-Ack
+
+   RUC  = Receive-Unknown-Code              scj = Send-Code-Reject
+   RXJ+ = Receive-Code-Reject (permitted)
+       or Receive-Protocol-Reject
+   RXJ- = Receive-Code-Reject (catastrophic)
+       or Receive-Protocol-Reject
+*/
+static int cp_table[EVENTS][STATES] = {
+       /* CLOSED     STOPPED STOPPING REQ_SENT ACK_RECV ACK_SENT OPENED
+            0           1         2       3       4      5          6    */
+       {IRC|SCR|3,     INV     , INV ,   INV   , INV ,  INV    ,   INV   }, /* START */
+       {   INV   ,      0      ,  0  ,    0    ,  0  ,   0     ,    0    }, /* STOP */
+       {   INV   ,     INV     ,STR|2,  SCR|3  ,SCR|3,  SCR|5  ,   INV   }, /* TO+ */
+       {   INV   ,     INV     ,  1  ,    1    ,  1  ,    1    ,   INV   }, /* TO- */
+       {  STA|0  ,IRC|SCR|SCA|5,  2  ,  SCA|5  ,SCA|6,  SCA|5  ,SCR|SCA|5}, /* RCR+ */
+       {  STA|0  ,IRC|SCR|SCN|3,  2  ,  SCN|3  ,SCN|4,  SCN|3  ,SCR|SCN|3}, /* RCR- */
+       {  STA|0  ,    STA|1    ,  2  ,  IRC|4  ,SCR|3,    6    , SCR|3   }, /* RCA */
+       {  STA|0  ,    STA|1    ,  2  ,IRC|SCR|3,SCR|3,IRC|SCR|5, SCR|3   }, /* RCN */
+       {  STA|0  ,    STA|1    ,STA|2,  STA|3  ,STA|3,  STA|3  ,ZRC|STA|2}, /* RTR */
+       {    0    ,      1      ,  1  ,    3    ,  3  ,    5    ,  SCR|3  }, /* RTA */
+       {  SCJ|0  ,    SCJ|1    ,SCJ|2,  SCJ|3  ,SCJ|4,  SCJ|5  ,  SCJ|6  }, /* RUC */
+       {    0    ,      1      ,  2  ,    3    ,  3  ,    5    ,    6    }, /* RXJ+ */
+       {    0    ,      1      ,  1  ,    1    ,  1  ,    1    ,IRC|STR|2}, /* RXJ- */
+};
+
 
-static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev)
+/* SCA: RCR+ must supply id, len and data
+   SCN: RCR- must supply code, id, len and data
+   STA: RTR must supply id
+   SCJ: RUC must supply CP packet len and data */
+static void ppp_cp_event(struct net_device *dev, u16 pid, u16 event, u8 code,
+                        u8 id, unsigned int len, void *data)
 {
-       return __constant_htons(ETH_P_WAN_PPP);
+       int old_state, action;
+       struct ppp *ppp = get_ppp(dev);
+       struct proto *proto = get_proto(dev, pid);
+
+       old_state = proto->state;
+       BUG_ON(old_state >= STATES);
+       BUG_ON(event >= EVENTS);
+
+#if DEBUG_STATE
+       printk(KERN_DEBUG "%s: %s ppp_cp_event(%s) %s ...\n", dev->name,
+              proto_name(pid), event_names[event], state_names[proto->state]);
+#endif
+
+       action = cp_table[event][old_state];
+
+       proto->state = action & STATE_MASK;
+       if (action & (SCR | STR)) /* set Configure-Req/Terminate-Req timer */
+               mod_timer(&proto->timer, proto->timeout =
+                         jiffies + ppp->req_timeout * HZ);
+       if (action & ZRC)
+               proto->restart_counter = 0;
+       if (action & IRC)
+               proto->restart_counter = (proto->state == STOPPING) ?
+                       ppp->term_retries : ppp->cr_retries;
+
+       if (action & SCR)       /* send Configure-Request */
+               ppp_tx_cp(dev, pid, CP_CONF_REQ, proto->cr_id = ++ppp->seq,
+                         0, NULL);
+       if (action & SCA)       /* send Configure-Ack */
+               ppp_tx_cp(dev, pid, CP_CONF_ACK, id, len, data);
+       if (action & SCN)       /* send Configure-Nak/Reject */
+               ppp_tx_cp(dev, pid, code, id, len, data);
+       if (action & STR)       /* send Terminate-Request */
+               ppp_tx_cp(dev, pid, CP_TERM_REQ, ++ppp->seq, 0, NULL);
+       if (action & STA)       /* send Terminate-Ack */
+               ppp_tx_cp(dev, pid, CP_TERM_ACK, id, 0, NULL);
+       if (action & SCJ)       /* send Code-Reject */
+               ppp_tx_cp(dev, pid, CP_CODE_REJ, ++ppp->seq, len, data);
+
+       if (old_state != OPENED && proto->state == OPENED) {
+               printk(KERN_INFO "%s: %s up\n", dev->name, proto_name(pid));
+               if (pid == PID_LCP) {
+                       netif_dormant_off(dev);
+                       ppp_cp_event(dev, PID_IPCP, START, 0, 0, 0, NULL);
+                       ppp_cp_event(dev, PID_IPV6CP, START, 0, 0, 0, NULL);
+                       ppp->last_pong = jiffies;
+                       mod_timer(&proto->timer, proto->timeout =
+                                 jiffies + ppp->keepalive_interval * HZ);
+               }
+       }
+       if (old_state == OPENED && proto->state != OPENED) {
+               printk(KERN_INFO "%s: %s down\n", dev->name, proto_name(pid));
+               if (pid == PID_LCP) {
+                       netif_dormant_on(dev);
+                       ppp_cp_event(dev, PID_IPCP, STOP, 0, 0, 0, NULL);
+                       ppp_cp_event(dev, PID_IPV6CP, STOP, 0, 0, 0, NULL);
+               }
+       }
+       if (old_state != CLOSED && proto->state == CLOSED)
+               del_timer(&proto->timer);
+
+#if DEBUG_STATE
+       printk(KERN_DEBUG "%s: %s ppp_cp_event(%s) ... %s\n", dev->name,
+              proto_name(pid), event_names[event], state_names[proto->state]);
+#endif
 }
 
 
+static void ppp_cp_parse_cr(struct net_device *dev, u16 pid, u8 id,
+                           unsigned int len, u8 *data)
+{
+       static u8 const valid_accm[6] = { LCP_OPTION_ACCM, 6, 0, 0, 0, 0 };
+       u8 *opt, *out;
+       unsigned int nak_len = 0, rej_len = 0;
+
+       if (!(out = kmalloc(len, GFP_ATOMIC))) {
+               dev->stats.rx_dropped++;
+               return; /* out of memory, ignore CR packet */
+       }
+
+       for (opt = data; len; len -= opt[1], opt += opt[1]) {
+               if (len < 2 || len < opt[1]) {
+                       dev->stats.rx_errors++;
+                       return; /* bad packet, drop silently */
+               }
+
+               if (pid == PID_LCP)
+                       switch (opt[0]) {
+                       case LCP_OPTION_MRU:
+                               continue; /* MRU always OK and > 1500 bytes? */
+
+                       case LCP_OPTION_ACCM: /* async control character map */
+                               if (!memcmp(opt, valid_accm,
+                                           sizeof(valid_accm)))
+                                       continue;
+                               if (!rej_len) { /* NAK it */
+                                       memcpy(out + nak_len, valid_accm,
+                                              sizeof(valid_accm));
+                                       nak_len += sizeof(valid_accm);
+                                       continue;
+                               }
+                               break;
+                       case LCP_OPTION_MAGIC:
+                               if (opt[1] != 6 || (!opt[2] && !opt[3] &&
+                                                   !opt[4] && !opt[5]))
+                                       break; /* reject invalid magic number */
+                               continue;
+                       }
+               /* reject this option */
+               memcpy(out + rej_len, opt, opt[1]);
+               rej_len += opt[1];
+       }
+
+       if (rej_len)
+               ppp_cp_event(dev, pid, RCR_BAD, CP_CONF_REJ, id, rej_len, out);
+       else if (nak_len)
+               ppp_cp_event(dev, pid, RCR_BAD, CP_CONF_NAK, id, nak_len, out);
+       else
+               ppp_cp_event(dev, pid, RCR_GOOD, CP_CONF_ACK, id, len, data);
+
+       kfree(out);
+}
+
+static int ppp_rx(struct sk_buff *skb)
+{
+       struct hdlc_header *hdr = (struct hdlc_header*)skb->data;
+       struct net_device *dev = skb->dev;
+       struct ppp *ppp = get_ppp(dev);
+       struct proto *proto;
+       struct cp_header *cp;
+       unsigned long flags;
+       unsigned int len;
+       u16 pid;
+#if DEBUG_CP
+       int i;
+       char *ptr;
+#endif
+
+       spin_lock_irqsave(&ppp->lock, flags);
+       /* Check HDLC header */
+       if (skb->len < sizeof(struct hdlc_header))
+               goto rx_error;
+       cp = (struct cp_header*)skb_pull(skb, sizeof(struct hdlc_header));
+       if (hdr->address != HDLC_ADDR_ALLSTATIONS ||
+           hdr->control != HDLC_CTRL_UI)
+               goto rx_error;
+
+       pid = ntohs(hdr->protocol);
+       proto = get_proto(dev, pid);
+       if (!proto) {
+               if (ppp->protos[IDX_LCP].state == OPENED)
+                       ppp_tx_cp(dev, PID_LCP, LCP_PROTO_REJ,
+                                 ++ppp->seq, skb->len + 2, &hdr->protocol);
+               goto rx_error;
+       }
+
+       len = ntohs(cp->len);
+       if (len < sizeof(struct cp_header) /* no complete CP header? */ ||
+           skb->len < len /* truncated packet? */)
+               goto rx_error;
+       skb_pull(skb, sizeof(struct cp_header));
+       len -= sizeof(struct cp_header);
+
+       /* HDLC and CP headers stripped from skb */
+#if DEBUG_CP
+       if (cp->code < CP_CODES)
+               sprintf(debug_buffer, "[%s id 0x%X]", code_names[cp->code],
+                       cp->id);
+       else
+               sprintf(debug_buffer, "[code %u id 0x%X]", cp->code, cp->id);
+       ptr = debug_buffer + strlen(debug_buffer);
+       for (i = 0; i < min_t(unsigned int, len, DEBUG_CP); i++) {
+               sprintf(ptr, " %02X", skb->data[i]);
+               ptr += strlen(ptr);
+       }
+       printk(KERN_DEBUG "%s: RX %s %s\n", dev->name, proto_name(pid),
+              debug_buffer);
+#endif
+
+       /* LCP only */
+       if (pid == PID_LCP)
+               switch (cp->code) {
+               case LCP_PROTO_REJ:
+                       pid = ntohs(*(__be16*)skb->data);
+                       if (pid == PID_LCP || pid == PID_IPCP ||
+                           pid == PID_IPV6CP)
+                               ppp_cp_event(dev, pid, RXJ_BAD, 0, 0,
+                                            0, NULL);
+                       goto out;
+
+               case LCP_ECHO_REQ: /* send Echo-Reply */
+                       if (len >= 4 && proto->state == OPENED)
+                               ppp_tx_cp(dev, PID_LCP, LCP_ECHO_REPLY,
+                                         cp->id, len - 4, skb->data + 4);
+                       goto out;
+
+               case LCP_ECHO_REPLY:
+                       if (cp->id == ppp->echo_id)
+                               ppp->last_pong = jiffies;
+                       goto out;
+
+               case LCP_DISC_REQ: /* discard */
+                       goto out;
+               }
+
+       /* LCP, IPCP and IPV6CP */
+       switch (cp->code) {
+       case CP_CONF_REQ:
+               ppp_cp_parse_cr(dev, pid, cp->id, len, skb->data);
+               goto out;
+
+       case CP_CONF_ACK:
+               if (cp->id == proto->cr_id)
+                       ppp_cp_event(dev, pid, RCA, 0, 0, 0, NULL);
+               goto out;
+
+       case CP_CONF_REJ:
+       case CP_CONF_NAK:
+               if (cp->id == proto->cr_id)
+                       ppp_cp_event(dev, pid, RCN, 0, 0, 0, NULL);
+               goto out;
+
+       case CP_TERM_REQ:
+               ppp_cp_event(dev, pid, RTR, 0, cp->id, 0, NULL);
+               goto out;
+
+       case CP_TERM_ACK:
+               ppp_cp_event(dev, pid, RTA, 0, 0, 0, NULL);
+               goto out;
+
+       case CP_CODE_REJ:
+               ppp_cp_event(dev, pid, RXJ_BAD, 0, 0, 0, NULL);
+               goto out;
+
+       default:
+               len += sizeof(struct cp_header);
+               if (len > dev->mtu)
+                       len = dev->mtu;
+               ppp_cp_event(dev, pid, RUC, 0, 0, len, cp);
+               goto out;
+       }
+       goto out;
+
+rx_error:
+       dev->stats.rx_errors++;
+out:
+       spin_unlock_irqrestore(&ppp->lock, flags);
+       dev_kfree_skb_any(skb);
+       ppp_tx_flush();
+       return NET_RX_DROP;
+}
+
+
+static void ppp_timer(unsigned long arg)
+{
+       struct proto *proto = (struct proto *)arg;
+       struct ppp *ppp = get_ppp(proto->dev);
+       unsigned long flags;
+
+       spin_lock_irqsave(&ppp->lock, flags);
+       switch (proto->state) {
+       case STOPPING:
+       case REQ_SENT:
+       case ACK_RECV:
+       case ACK_SENT:
+               if (proto->restart_counter) {
+                       ppp_cp_event(proto->dev, proto->pid, TO_GOOD, 0, 0,
+                                    0, NULL);
+                       proto->restart_counter--;
+               } else
+                       ppp_cp_event(proto->dev, proto->pid, TO_BAD, 0, 0,
+                                    0, NULL);
+               break;
+
+       case OPENED:
+               if (proto->pid != PID_LCP)
+                       break;
+               if (time_after(jiffies, ppp->last_pong +
+                              ppp->keepalive_timeout * HZ)) {
+                       printk(KERN_INFO "%s: Link down\n", proto->dev->name);
+                       ppp_cp_event(proto->dev, PID_LCP, STOP, 0, 0, 0, NULL);
+                       ppp_cp_event(proto->dev, PID_LCP, START, 0, 0, 0, NULL);
+               } else {        /* send keep-alive packet */
+                       ppp->echo_id = ++ppp->seq;
+                       ppp_tx_cp(proto->dev, PID_LCP, LCP_ECHO_REQ,
+                                 ppp->echo_id, 0, NULL);
+                       proto->timer.expires = jiffies +
+                               ppp->keepalive_interval * HZ;
+                       add_timer(&proto->timer);
+               }
+               break;
+       }
+       spin_unlock_irqrestore(&ppp->lock, flags);
+       ppp_tx_flush();
+}
+
+
+static void ppp_start(struct net_device *dev)
+{
+       struct ppp *ppp = get_ppp(dev);
+       int i;
+
+       for (i = 0; i < IDX_COUNT; i++) {
+               struct proto *proto = &ppp->protos[i];
+               proto->dev = dev;
+               init_timer(&proto->timer);
+               proto->timer.function = ppp_timer;
+               proto->timer.data = (unsigned long)proto;
+               proto->state = CLOSED;
+       }
+       ppp->protos[IDX_LCP].pid = PID_LCP;
+       ppp->protos[IDX_IPCP].pid = PID_IPCP;
+       ppp->protos[IDX_IPV6CP].pid = PID_IPV6CP;
+
+       ppp_cp_event(dev, PID_LCP, START, 0, 0, 0, NULL);
+}
+
+static void ppp_stop(struct net_device *dev)
+{
+       ppp_cp_event(dev, PID_LCP, STOP, 0, 0, 0, NULL);
+}
 
 static struct hdlc_proto proto = {
-       .open           = ppp_open,
-       .close          = ppp_close,
+       .start          = ppp_start,
+       .stop           = ppp_stop,
        .type_trans     = ppp_type_trans,
        .ioctl          = ppp_ioctl,
+       .netif_rx       = ppp_rx,
        .module         = THIS_MODULE,
 };
 
+static const struct header_ops ppp_header_ops = {
+       .create = ppp_hard_header,
+};
 
 static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
 {
        hdlc_device *hdlc = dev_to_hdlc(dev);
+       struct ppp *ppp;
        int result;
 
        switch (ifr->ifr_settings.type) {
@@ -109,25 +654,35 @@ static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
                return 0; /* return protocol only, no settable parameters */
 
        case IF_PROTO_PPP:
-               if(!capable(CAP_NET_ADMIN))
+               if (!capable(CAP_NET_ADMIN))
                        return -EPERM;
 
-               if(dev->flags & IFF_UP)
+               if (dev->flags & IFF_UP)
                        return -EBUSY;
 
                /* no settable parameters */
 
-               result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
+               result = hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
                if (result)
                        return result;
 
-               result = attach_hdlc_protocol(dev, &proto,
-                                             sizeof(struct ppp_state));
+               result = attach_hdlc_protocol(dev, &proto, sizeof(struct ppp));
                if (result)
                        return result;
+
+               ppp = get_ppp(dev);
+               spin_lock_init(&ppp->lock);
+               ppp->req_timeout = 2;
+               ppp->cr_retries = 10;
+               ppp->term_retries = 2;
+               ppp->keepalive_interval = 10;
+               ppp->keepalive_timeout = 60;
+
                dev->hard_start_xmit = hdlc->xmit;
+               dev->hard_header_len = sizeof(struct hdlc_header);
+               dev->header_ops = &ppp_header_ops;
                dev->type = ARPHRD_PPP;
-               netif_dormant_off(dev);
+               netif_dormant_on(dev);
                return 0;
        }
 
@@ -137,12 +692,11 @@ static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
 
 static int __init mod_init(void)
 {
+       skb_queue_head_init(&tx_queue);
        register_hdlc_protocol(&proto);
        return 0;
 }
 
-
-
 static void __exit mod_exit(void)
 {
        unregister_hdlc_protocol(&proto);