1 files changed, 491 insertions, 0 deletions

diff --git a/net/irda/irlmp_frame.c b/net/irda/irlmp_frame.c
new file mode 100644
index 000000000000..91cd268172fa
--- /dev/null
+++ b/net/irda/irlmp_frame.c
@@ -0,0 +1,491 @@
+/*********************************************************************
+ *                
+ * Filename:      irlmp_frame.c
+ * Version:       0.9
+ * Description:   IrLMP frame implementation
+ * Status:        Experimental.
+ * Author:        Dag Brattli <dagb@cs.uit.no>
+ * Created at:    Tue Aug 19 02:09:59 1997
+ * Modified at:   Mon Dec 13 13:41:12 1999
+ * Modified by:   Dag Brattli <dagb@cs.uit.no>
+ * 
+ *     Copyright (c) 1998-1999 Dag Brattli <dagb@cs.uit.no>
+ *     All Rights Reserved.
+ *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
+ *     
+ *     This program is free software; you can redistribute it and/or 
+ *     modify it under the terms of the GNU General Public License as 
+ *     published by the Free Software Foundation; either version 2 of 
+ *     the License, or (at your option) any later version.
+ *
+ *     Neither Dag Brattli nor University of Tromsų admit liability nor
+ *     provide warranty for any of this software. This material is 
+ *     provided "AS-IS" and at no charge.
+ *
+ ********************************************************************/
+
+#include <linux/config.h>
+#include <linux/skbuff.h>
+#include <linux/kernel.h>
+
+#include <net/irda/irda.h>
+#include <net/irda/irlap.h>
+#include <net/irda/timer.h>
+#include <net/irda/irlmp.h>
+#include <net/irda/irlmp_frame.h>
+#include <net/irda/discovery.h>
+
+static struct lsap_cb *irlmp_find_lsap(struct lap_cb *self, __u8 dlsap, 
+                                       __u8 slsap, int status, hashbin_t *);
+
+inline void irlmp_send_data_pdu(struct lap_cb *self, __u8 dlsap, __u8 slsap,
+                                int expedited, struct sk_buff *skb)
+{
+        skb->data[0] = dlsap;
+        skb->data[1] = slsap;
+
+        if (expedited) {
+                IRDA_DEBUG(4, "%s(), sending expedited data\n", __FUNCTION__);
+                irlap_data_request(self->irlap, skb, TRUE);
+        } else
+                irlap_data_request(self->irlap, skb, FALSE);
+}
+
+/*
+ * Function irlmp_send_lcf_pdu (dlsap, slsap, opcode,skb)
+ *
+ *    Send Link Control Frame to IrLAP
+ */
+void irlmp_send_lcf_pdu(struct lap_cb *self, __u8 dlsap, __u8 slsap,
+                        __u8 opcode, struct sk_buff *skb) 
+{
+        __u8 *frame;
+        
+        IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
+
+        IRDA_ASSERT(self != NULL, return;);
+        IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
+        IRDA_ASSERT(skb != NULL, return;);
+        
+        frame = skb->data;
+        
+        frame[0] = dlsap | CONTROL_BIT;
+        frame[1] = slsap;
+
+        frame[2] = opcode;
+
+        if (opcode == DISCONNECT)
+                frame[3] = 0x01; /* Service user request */
+        else
+                frame[3] = 0x00; /* rsvd */
+
+        irlap_data_request(self->irlap, skb, FALSE);
+}
+
+/*
+ * Function irlmp_input (skb)
+ *
+ *    Used by IrLAP to pass received data frames to IrLMP layer
+ *
+ */
+void irlmp_link_data_indication(struct lap_cb *self, struct sk_buff *skb, 
+                                int unreliable)
+{
+        struct lsap_cb *lsap;
+        __u8   slsap_sel;   /* Source (this) LSAP address */
+        __u8   dlsap_sel;   /* Destination LSAP address */
+        __u8   *fp;
+        
+        IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+        IRDA_ASSERT(self != NULL, return;);
+        IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
+        IRDA_ASSERT(skb->len > 2, return;);
+
+        fp = skb->data;
+
+        /*
+         *  The next statements may be confusing, but we do this so that 
+         *  destination LSAP of received frame is source LSAP in our view
+         */
+        slsap_sel = fp[0] & LSAP_MASK; 
+        dlsap_sel = fp[1];      
+
+        /*
+         *  Check if this is an incoming connection, since we must deal with
+         *  it in a different way than other established connections.
+         */
+        if ((fp[0] & CONTROL_BIT) && (fp[2] == CONNECT_CMD)) {
+                IRDA_DEBUG(3, "%s(), incoming connection, "
+                           "source LSAP=%d, dest LSAP=%d\n",
+                           __FUNCTION__, slsap_sel, dlsap_sel);
+                
+                /* Try to find LSAP among the unconnected LSAPs */
+                lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, CONNECT_CMD,
+                                       irlmp->unconnected_lsaps);
+                
+                /* Maybe LSAP was already connected, so try one more time */
+                if (!lsap) {
+                        IRDA_DEBUG(1, "%s(), incoming connection for LSAP already connected\n", __FUNCTION__);
+                        lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, 0,
+                                               self->lsaps);
+                }
+        } else
+                lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, 0, 
+                                       self->lsaps);
+        
+        if (lsap == NULL) {
+                IRDA_DEBUG(2, "IrLMP, Sorry, no LSAP for received frame!\n");
+                IRDA_DEBUG(2, "%s(), slsap_sel = %02x, dlsap_sel = %02x\n",
+                           __FUNCTION__, slsap_sel, dlsap_sel);
+                if (fp[0] & CONTROL_BIT) {
+                        IRDA_DEBUG(2, "%s(), received control frame %02x\n",
+                                   __FUNCTION__, fp[2]);
+                } else {
+                        IRDA_DEBUG(2, "%s(), received data frame\n", __FUNCTION__);
+                }
+                return;
+        }
+
+        /* 
+         *  Check if we received a control frame? 
+         */
+        if (fp[0] & CONTROL_BIT) {
+                switch (fp[2]) {
+                case CONNECT_CMD:
+                        lsap->lap = self;
+                        irlmp_do_lsap_event(lsap, LM_CONNECT_INDICATION, skb);
+                        break;
+                case CONNECT_CNF:
+                        irlmp_do_lsap_event(lsap, LM_CONNECT_CONFIRM, skb);
+                        break;
+                case DISCONNECT:
+                        IRDA_DEBUG(4, "%s(), Disconnect indication!\n",
+                                   __FUNCTION__);
+                        irlmp_do_lsap_event(lsap, LM_DISCONNECT_INDICATION, 
+                                            skb);
+                        break;
+                case ACCESSMODE_CMD:
+                        IRDA_DEBUG(0, "Access mode cmd not implemented!\n");
+                        break;
+                case ACCESSMODE_CNF:
+                        IRDA_DEBUG(0, "Access mode cnf not implemented!\n");
+                        break;
+                default:
+                        IRDA_DEBUG(0, "%s(), Unknown control frame %02x\n",
+                                   __FUNCTION__, fp[2]);
+                        break;
+                }
+        } else if (unreliable) {
+                /* Optimize and bypass the state machine if possible */
+                if (lsap->lsap_state == LSAP_DATA_TRANSFER_READY)
+                        irlmp_udata_indication(lsap, skb);
+                else
+                        irlmp_do_lsap_event(lsap, LM_UDATA_INDICATION, skb);
+        } else {        
+                /* Optimize and bypass the state machine if possible */
+                if (lsap->lsap_state == LSAP_DATA_TRANSFER_READY)
+                        irlmp_data_indication(lsap, skb);
+                else
+                        irlmp_do_lsap_event(lsap, LM_DATA_INDICATION, skb);
+        }
+}
+
+/*
+ * Function irlmp_link_unitdata_indication (self, skb)
+ *
+ *    
+ *
+ */
+#ifdef CONFIG_IRDA_ULTRA
+void irlmp_link_unitdata_indication(struct lap_cb *self, struct sk_buff *skb)
+{
+        struct lsap_cb *lsap;
+        __u8   slsap_sel;   /* Source (this) LSAP address */
+        __u8   dlsap_sel;   /* Destination LSAP address */
+        __u8   pid;         /* Protocol identifier */
+        __u8   *fp;
+        unsigned long flags;
+        
+        IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+        IRDA_ASSERT(self != NULL, return;);
+        IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
+        IRDA_ASSERT(skb->len > 2, return;);
+
+        fp = skb->data;
+
+        /*
+         *  The next statements may be confusing, but we do this so that 
+         *  destination LSAP of received frame is source LSAP in our view
+         */
+        slsap_sel = fp[0] & LSAP_MASK; 
+        dlsap_sel = fp[1];
+        pid       = fp[2];
+        
+        if (pid & 0x80) {
+                IRDA_DEBUG(0, "%s(), extension in PID not supp!\n",
+                           __FUNCTION__);
+                return;
+        }
+
+        /* Check if frame is addressed to the connectionless LSAP */
+        if ((slsap_sel != LSAP_CONNLESS) || (dlsap_sel != LSAP_CONNLESS)) {
+                IRDA_DEBUG(0, "%s(), dropping frame!\n", __FUNCTION__);
+                return;
+        }
+        
+        /* Search the connectionless LSAP */
+        spin_lock_irqsave(&irlmp->unconnected_lsaps->hb_spinlock, flags);
+        lsap = (struct lsap_cb *) hashbin_get_first(irlmp->unconnected_lsaps);
+        while (lsap != NULL) {
+                /*
+                 *  Check if source LSAP and dest LSAP selectors and PID match.
+                 */
+                if ((lsap->slsap_sel == slsap_sel) && 
+                    (lsap->dlsap_sel == dlsap_sel) && 
+                    (lsap->pid == pid)) 
+                {                       
+                        break;
+                }
+                lsap = (struct lsap_cb *) hashbin_get_next(irlmp->unconnected_lsaps);
+        }
+        spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock, flags);
+
+        if (lsap)
+                irlmp_connless_data_indication(lsap, skb);
+        else {
+                IRDA_DEBUG(0, "%s(), found no matching LSAP!\n", __FUNCTION__);
+        }
+}
+#endif /* CONFIG_IRDA_ULTRA */
+
+/*
+ * Function irlmp_link_disconnect_indication (reason, userdata)
+ *
+ *    IrLAP has disconnected 
+ *
+ */
+void irlmp_link_disconnect_indication(struct lap_cb *lap, 
+                                      struct irlap_cb *irlap, 
+                                      LAP_REASON reason, 
+                                      struct sk_buff *skb)
+{
+        IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
+
+        IRDA_ASSERT(lap != NULL, return;);
+        IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, return;);
+
+        lap->reason = reason;
+        lap->daddr = DEV_ADDR_ANY;
+
+        /* FIXME: must do something with the skb if any */
+        
+        /*
+         *  Inform station state machine
+         */
+        irlmp_do_lap_event(lap, LM_LAP_DISCONNECT_INDICATION, NULL);
+}
+
+/*
+ * Function irlmp_link_connect_indication (qos)
+ *
+ *    Incoming LAP connection!
+ *
+ */
+void irlmp_link_connect_indication(struct lap_cb *self, __u32 saddr, 
+                                   __u32 daddr, struct qos_info *qos,
+                                   struct sk_buff *skb) 
+{
+        IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+        /* Copy QoS settings for this session */
+        self->qos = qos;
+
+        /* Update destination device address */
+        self->daddr = daddr;
+        IRDA_ASSERT(self->saddr == saddr, return;);
+
+        irlmp_do_lap_event(self, LM_LAP_CONNECT_INDICATION, skb);
+}
+
+/*
+ * Function irlmp_link_connect_confirm (qos)
+ *
+ *    LAP connection confirmed!
+ *
+ */
+void irlmp_link_connect_confirm(struct lap_cb *self, struct qos_info *qos, 
+                                struct sk_buff *skb)
+{
+        IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+        IRDA_ASSERT(self != NULL, return;);
+        IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
+        IRDA_ASSERT(qos != NULL, return;);
+
+        /* Don't need use the skb for now */
+
+        /* Copy QoS settings for this session */
+        self->qos = qos;
+
+        irlmp_do_lap_event(self, LM_LAP_CONNECT_CONFIRM, NULL);
+}
+
+/*
+ * Function irlmp_link_discovery_indication (self, log)
+ *
+ *    Device is discovering us
+ *
+ * It's not an answer to our own discoveries, just another device trying
+ * to perform discovery, but we don't want to miss the opportunity
+ * to exploit this information, because :
+ *      o We may not actively perform discovery (just passive discovery)
+ *      o This type of discovery is much more reliable. In some cases, it
+ *        seem that less than 50% of our discoveries get an answer, while
+ *        we always get ~100% of these.
+ *      o Make faster discovery, statistically divide time of discovery
+ *        events by 2 (important for the latency aspect and user feel)
+ *      o Even is we do active discovery, the other node might not
+ *        answer our discoveries (ex: Palm). The Palm will just perform
+ *        one active discovery and connect directly to us.
+ *
+ * However, when both devices discover each other, they might attempt to
+ * connect to each other following the discovery event, and it would create
+ * collisions on the medium (SNRM battle).
+ * The "fix" for that is to disable all connection requests in IrLAP
+ * for 100ms after a discovery indication by setting the media_busy flag.
+ * Previously, we used to postpone the event which was quite ugly. Now
+ * that IrLAP takes care of this problem, just pass the event up...
+ *
+ * Jean II
+ */
+void irlmp_link_discovery_indication(struct lap_cb *self, 
+                                     discovery_t *discovery)
+{
+        IRDA_ASSERT(self != NULL, return;);
+        IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
+
+        /* Add to main log, cleanup */
+        irlmp_add_discovery(irlmp->cachelog, discovery);
+        
+        /* Just handle it the same way as a discovery confirm,
+         * bypass the LM_LAP state machine (see below) */
+        irlmp_discovery_confirm(irlmp->cachelog, DISCOVERY_PASSIVE);
+}
+
+/*
+ * Function irlmp_link_discovery_confirm (self, log)
+ *
+ *    Called by IrLAP with a list of discoveries after the discovery
+ *    request has been carried out. A NULL log is received if IrLAP
+ *    was unable to carry out the discovery request
+ *
+ */
+void irlmp_link_discovery_confirm(struct lap_cb *self, hashbin_t *log)
+{
+        IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+        IRDA_ASSERT(self != NULL, return;);
+        IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
+        
+        /* Add to main log, cleanup */
+        irlmp_add_discovery_log(irlmp->cachelog, log);
+
+        /* Propagate event to various LSAPs registered for it.
+         * We bypass the LM_LAP state machine because
+         *      1) We do it regardless of the LM_LAP state
+         *      2) It doesn't affect the LM_LAP state
+         *      3) Faster, slimer, simpler, ...
+         * Jean II */
+        irlmp_discovery_confirm(irlmp->cachelog, DISCOVERY_ACTIVE);
+}
+
+#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
+static inline void irlmp_update_cache(struct lap_cb *lap,
+                                      struct lsap_cb *lsap)
+{
+        /* Prevent concurrent read to get garbage */
+        lap->cache.valid = FALSE;
+        /* Update cache entry */
+        lap->cache.dlsap_sel = lsap->dlsap_sel;
+        lap->cache.slsap_sel = lsap->slsap_sel;
+        lap->cache.lsap = lsap;
+        lap->cache.valid = TRUE;
+}
+#endif
+
+/*
+ * Function irlmp_find_handle (self, dlsap_sel, slsap_sel, status, queue)
+ *
+ *    Find handle associated with destination and source LSAP
+ *
+ * Any IrDA connection (LSAP/TSAP) is uniquely identified by
+ * 3 parameters, the local lsap, the remote lsap and the remote address. 
+ * We may initiate multiple connections to the same remote service
+ * (they will have different local lsap), a remote device may initiate
+ * multiple connections to the same local service (they will have
+ * different remote lsap), or multiple devices may connect to the same
+ * service and may use the same remote lsap (and they will have
+ * different remote address).
+ * So, where is the remote address ? Each LAP connection is made with
+ * a single remote device, so imply a specific remote address.
+ * Jean II
+ */
+static struct lsap_cb *irlmp_find_lsap(struct lap_cb *self, __u8 dlsap_sel,
+                                       __u8 slsap_sel, int status,
+                                       hashbin_t *queue) 
+{
+        struct lsap_cb *lsap;
+        unsigned long flags;
+        
+        /* 
+         *  Optimize for the common case. We assume that the last frame
+         *  received is in the same connection as the last one, so check in
+         *  cache first to avoid the linear search
+         */
+#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
+        if ((self->cache.valid) && 
+            (self->cache.slsap_sel == slsap_sel) && 
+            (self->cache.dlsap_sel == dlsap_sel)) 
+        {
+                return (self->cache.lsap);
+        }
+#endif
+
+        spin_lock_irqsave(&queue->hb_spinlock, flags);
+
+        lsap = (struct lsap_cb *) hashbin_get_first(queue);
+        while (lsap != NULL) {
+                /* 
+                 *  If this is an incoming connection, then the destination 
+                 *  LSAP selector may have been specified as LM_ANY so that 
+                 *  any client can connect. In that case we only need to check
+                 *  if the source LSAP (in our view!) match!
+                 */
+                if ((status == CONNECT_CMD) && 
+                    (lsap->slsap_sel == slsap_sel) &&      
+                    (lsap->dlsap_sel == LSAP_ANY)) {
+                        /* This is where the dest lsap sel is set on incoming
+                         * lsaps */
+                        lsap->dlsap_sel = dlsap_sel;
+                        break;
+                }
+                /*
+                 *  Check if source LSAP and dest LSAP selectors match.
+                 */
+                if ((lsap->slsap_sel == slsap_sel) && 
+                    (lsap->dlsap_sel == dlsap_sel)) 
+                        break;
+
+                lsap = (struct lsap_cb *) hashbin_get_next(queue);
+        }
+#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
+        if(lsap)
+                irlmp_update_cache(self, lsap);
+#endif
+        spin_unlock_irqrestore(&queue->hb_spinlock, flags);
+
+        /* Return what we've found or NULL */
+        return lsap;
+}