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Diffstat (limited to 'drivers/net/wan/hdlc_ppp.c')
-rw-r--r--drivers/net/wan/hdlc_ppp.c725
1 files changed, 725 insertions, 0 deletions
diff --git a/drivers/net/wan/hdlc_ppp.c b/drivers/net/wan/hdlc_ppp.c
new file mode 100644
index 0000000000..37a3c989cb
--- /dev/null
+++ b/drivers/net/wan/hdlc_ppp.c
@@ -0,0 +1,725 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Generic HDLC support routines for Linux
+ * Point-to-point protocol support
+ *
+ * Copyright (C) 1999 - 2008 Krzysztof Halasa <khc@pm.waw.pl>
+ */
+
+#include <linux/errno.h>
+#include <linux/hdlc.h>
+#include <linux/if_arp.h>
+#include <linux/inetdevice.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pkt_sched.h>
+#include <linux/poll.h>
+#include <linux/skbuff.h>
+#include <linux/slab.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 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 if_settings *ifs);
+
+static inline struct ppp *get_ppp(struct net_device *dev)
+{
+ return (struct ppp *)dev_to_hdlc(dev)->state;
+}
+
+static inline struct proto *get_proto(struct net_device *dev, u16 pid)
+{
+ 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 __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev)
+{
+ 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 cpu_to_be16(PID_IP):
+ skb_pull(skb, sizeof(struct hdlc_header));
+ return htons(ETH_P_IP);
+
+ case cpu_to_be16(PID_IPV6):
+ skb_pull(skb, sizeof(struct hdlc_header));
+ return htons(ETH_P_IPV6);
+
+ default:
+ return htons(ETH_P_HDLC);
+ }
+}
+
+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_tx_cp(struct net_device *dev, u16 pid, u8 code,
+ u8 id, unsigned int len, const void *data)
+{
+ 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)
+ return;
+
+ skb_reserve(skb, sizeof(struct hdlc_header));
+
+ cp = 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)
+ skb_put_data(skb, &magic, magic_len);
+ if (len)
+ skb_put_data(skb, 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
+
+ ppp_hard_header(skb, dev, pid, NULL, NULL, 0);
+
+ skb->priority = TC_PRIO_CONTROL;
+ skb->dev = dev;
+ skb->protocol = htons(ETH_P_HDLC);
+ 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- */
+};
+
+/* 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, const void *data)
+{
+ 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) {
+ netdev_info(dev, "%s up\n", 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) {
+ netdev_info(dev, "%s down\n", 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 req_len, const u8 *data)
+{
+ static u8 const valid_accm[6] = { LCP_OPTION_ACCM, 6, 0, 0, 0, 0 };
+ const u8 *opt;
+ u8 *out;
+ unsigned int len = req_len, nak_len = 0, rej_len = 0;
+
+ out = kmalloc(len, GFP_ATOMIC);
+ if (!out) {
+ dev->stats.rx_dropped++;
+ return; /* out of memory, ignore CR packet */
+ }
+
+ for (opt = data; len; len -= opt[1], opt += opt[1]) {
+ if (len < 2 || opt[1] < 2 || len < opt[1])
+ goto err_out;
+
+ 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 (opt[1] < sizeof(valid_accm))
+ goto err_out;
+ 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 (len < 6)
+ goto err_out;
+ 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, req_len, data);
+
+ kfree(out);
+ return;
+
+err_out:
+ dev->stats.rx_errors++;
+ 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 = 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);
+ break;
+
+ case CP_CONF_ACK:
+ if (cp->id == proto->cr_id)
+ ppp_cp_event(dev, pid, RCA, 0, 0, 0, NULL);
+ break;
+
+ case CP_CONF_REJ:
+ case CP_CONF_NAK:
+ if (cp->id == proto->cr_id)
+ ppp_cp_event(dev, pid, RCN, 0, 0, 0, NULL);
+ break;
+
+ case CP_TERM_REQ:
+ ppp_cp_event(dev, pid, RTR, 0, cp->id, 0, NULL);
+ break;
+
+ case CP_TERM_ACK:
+ ppp_cp_event(dev, pid, RTA, 0, 0, 0, NULL);
+ break;
+
+ case CP_CODE_REJ:
+ ppp_cp_event(dev, pid, RXJ_BAD, 0, 0, 0, NULL);
+ break;
+
+ default:
+ len += sizeof(struct cp_header);
+ if (len > dev->mtu)
+ len = dev->mtu;
+ ppp_cp_event(dev, pid, RUC, 0, 0, len, cp);
+ break;
+ }
+ 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(struct timer_list *t)
+{
+ struct proto *proto = from_timer(proto, t, timer);
+ struct ppp *ppp = get_ppp(proto->dev);
+ unsigned long flags;
+
+ spin_lock_irqsave(&ppp->lock, flags);
+ /* mod_timer could be called after we entered this function but
+ * before we got the lock.
+ */
+ if (timer_pending(&proto->timer)) {
+ spin_unlock_irqrestore(&ppp->lock, flags);
+ return;
+ }
+ 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 if (netif_carrier_ok(proto->dev))
+ ppp_cp_event(proto->dev, proto->pid, TO_GOOD, 0, 0,
+ 0, NULL);
+ 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)) {
+ netdev_info(proto->dev, "Link down\n");
+ 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;
+ timer_setup(&proto->timer, ppp_timer, 0);
+ 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 void ppp_close(struct net_device *dev)
+{
+ ppp_tx_flush();
+}
+
+static struct hdlc_proto proto = {
+ .start = ppp_start,
+ .stop = ppp_stop,
+ .close = ppp_close,
+ .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 if_settings *ifs)
+{
+ hdlc_device *hdlc = dev_to_hdlc(dev);
+ struct ppp *ppp;
+ int result;
+
+ switch (ifs->type) {
+ case IF_GET_PROTO:
+ if (dev_to_hdlc(dev)->proto != &proto)
+ return -EINVAL;
+ ifs->type = IF_PROTO_PPP;
+ return 0; /* return protocol only, no settable parameters */
+
+ case IF_PROTO_PPP:
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
+ if (dev->flags & IFF_UP)
+ return -EBUSY;
+
+ /* no settable parameters */
+
+ result = hdlc->attach(dev, ENCODING_NRZ,
+ PARITY_CRC16_PR1_CCITT);
+ if (result)
+ return result;
+
+ 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_header_len = sizeof(struct hdlc_header);
+ dev->header_ops = &ppp_header_ops;
+ dev->type = ARPHRD_PPP;
+ call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
+ netif_dormant_on(dev);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int __init hdlc_ppp_init(void)
+{
+ skb_queue_head_init(&tx_queue);
+ register_hdlc_protocol(&proto);
+ return 0;
+}
+
+static void __exit hdlc_ppp_exit(void)
+{
+ unregister_hdlc_protocol(&proto);
+}
+
+module_init(hdlc_ppp_init);
+module_exit(hdlc_ppp_exit);
+
+MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
+MODULE_DESCRIPTION("PPP protocol support for generic HDLC");
+MODULE_LICENSE("GPL v2");