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-rw-r--r--net/irda/irlap_frame.c1437
1 files changed, 1437 insertions, 0 deletions
diff --git a/net/irda/irlap_frame.c b/net/irda/irlap_frame.c
new file mode 100644
index 0000000..040abe7
--- /dev/null
+++ b/net/irda/irlap_frame.c
@@ -0,0 +1,1437 @@
+/*********************************************************************
+ *
+ * Filename: irlap_frame.c
+ * Version: 1.0
+ * Description: Build and transmit IrLAP frames
+ * Status: Stable
+ * Author: Dag Brattli <dagb@cs.uit.no>
+ * Created at: Tue Aug 19 10:27:26 1997
+ * Modified at: Wed Jan 5 08:59:04 2000
+ * Modified by: Dag Brattli <dagb@cs.uit.no>
+ *
+ * Copyright (c) 1998-2000 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/skbuff.h>
+#include <linux/if.h>
+#include <linux/if_ether.h>
+#include <linux/netdevice.h>
+#include <linux/irda.h>
+
+#include <net/pkt_sched.h>
+#include <net/sock.h>
+
+#include <asm/byteorder.h>
+
+#include <net/irda/irda.h>
+#include <net/irda/irda_device.h>
+#include <net/irda/irlap.h>
+#include <net/irda/wrapper.h>
+#include <net/irda/timer.h>
+#include <net/irda/irlap_frame.h>
+#include <net/irda/qos.h>
+
+static void irlap_send_i_frame(struct irlap_cb *self, struct sk_buff *skb,
+ int command);
+
+/*
+ * Function irlap_insert_info (self, skb)
+ *
+ * Insert minimum turnaround time and speed information into the skb. We
+ * need to do this since it's per packet relevant information. Safe to
+ * have this function inlined since it's only called from one place
+ */
+static inline void irlap_insert_info(struct irlap_cb *self,
+ struct sk_buff *skb)
+{
+ struct irda_skb_cb *cb = (struct irda_skb_cb *) skb->cb;
+
+ /*
+ * Insert MTT (min. turn time) and speed into skb, so that the
+ * device driver knows which settings to use
+ */
+ cb->magic = LAP_MAGIC;
+ cb->mtt = self->mtt_required;
+ cb->next_speed = self->speed;
+
+ /* Reset */
+ self->mtt_required = 0;
+
+ /*
+ * Delay equals negotiated BOFs count, plus the number of BOFs to
+ * force the negotiated minimum turnaround time
+ */
+ cb->xbofs = self->bofs_count;
+ cb->next_xbofs = self->next_bofs;
+ cb->xbofs_delay = self->xbofs_delay;
+
+ /* Reset XBOF's delay (used only for getting min turn time) */
+ self->xbofs_delay = 0;
+ /* Put the correct xbofs value for the next packet */
+ self->bofs_count = self->next_bofs;
+}
+
+/*
+ * Function irlap_queue_xmit (self, skb)
+ *
+ * A little wrapper for dev_queue_xmit, so we can insert some common
+ * code into it.
+ */
+void irlap_queue_xmit(struct irlap_cb *self, struct sk_buff *skb)
+{
+ /* Some common init stuff */
+ skb->dev = self->netdev;
+ skb->h.raw = skb->nh.raw = skb->mac.raw = skb->data;
+ skb->protocol = htons(ETH_P_IRDA);
+ skb->priority = TC_PRIO_BESTEFFORT;
+
+ irlap_insert_info(self, skb);
+
+ dev_queue_xmit(skb);
+}
+
+/*
+ * Function irlap_send_snrm_cmd (void)
+ *
+ * Transmits a connect SNRM command frame
+ */
+void irlap_send_snrm_frame(struct irlap_cb *self, struct qos_info *qos)
+{
+ struct sk_buff *tx_skb;
+ struct snrm_frame *frame;
+ int ret;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+ /* Allocate frame */
+ tx_skb = dev_alloc_skb(64);
+ if (!tx_skb)
+ return;
+
+ frame = (struct snrm_frame *) skb_put(tx_skb, 2);
+
+ /* Insert connection address field */
+ if (qos)
+ frame->caddr = CMD_FRAME | CBROADCAST;
+ else
+ frame->caddr = CMD_FRAME | self->caddr;
+
+ /* Insert control field */
+ frame->control = SNRM_CMD | PF_BIT;
+
+ /*
+ * If we are establishing a connection then insert QoS paramerters
+ */
+ if (qos) {
+ skb_put(tx_skb, 9); /* 21 left */
+ frame->saddr = cpu_to_le32(self->saddr);
+ frame->daddr = cpu_to_le32(self->daddr);
+
+ frame->ncaddr = self->caddr;
+
+ ret = irlap_insert_qos_negotiation_params(self, tx_skb);
+ if (ret < 0) {
+ dev_kfree_skb(tx_skb);
+ return;
+ }
+ }
+ irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_snrm_cmd (skb, info)
+ *
+ * Received SNRM (Set Normal Response Mode) command frame
+ *
+ */
+static void irlap_recv_snrm_cmd(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info)
+{
+ struct snrm_frame *frame;
+
+ if (pskb_may_pull(skb,sizeof(struct snrm_frame))) {
+ frame = (struct snrm_frame *) skb->data;
+
+ /* Copy the new connection address ignoring the C/R bit */
+ info->caddr = frame->ncaddr & 0xFE;
+
+ /* Check if the new connection address is valid */
+ if ((info->caddr == 0x00) || (info->caddr == 0xfe)) {
+ IRDA_DEBUG(3, "%s(), invalid connection address!\n",
+ __FUNCTION__);
+ return;
+ }
+
+ /* Copy peer device address */
+ info->daddr = le32_to_cpu(frame->saddr);
+ info->saddr = le32_to_cpu(frame->daddr);
+
+ /* Only accept if addressed directly to us */
+ if (info->saddr != self->saddr) {
+ IRDA_DEBUG(2, "%s(), not addressed to us!\n",
+ __FUNCTION__);
+ return;
+ }
+ irlap_do_event(self, RECV_SNRM_CMD, skb, info);
+ } else {
+ /* Signal that this SNRM frame does not contain and I-field */
+ irlap_do_event(self, RECV_SNRM_CMD, skb, NULL);
+ }
+}
+
+/*
+ * Function irlap_send_ua_response_frame (qos)
+ *
+ * Send UA (Unnumbered Acknowledgement) frame
+ *
+ */
+void irlap_send_ua_response_frame(struct irlap_cb *self, struct qos_info *qos)
+{
+ struct sk_buff *tx_skb;
+ struct ua_frame *frame;
+ int ret;
+
+ IRDA_DEBUG(2, "%s() <%ld>\n", __FUNCTION__, jiffies);
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+ /* Allocate frame */
+ tx_skb = dev_alloc_skb(64);
+ if (!tx_skb)
+ return;
+
+ frame = (struct ua_frame *) skb_put(tx_skb, 10);
+
+ /* Build UA response */
+ frame->caddr = self->caddr;
+ frame->control = UA_RSP | PF_BIT;
+
+ frame->saddr = cpu_to_le32(self->saddr);
+ frame->daddr = cpu_to_le32(self->daddr);
+
+ /* Should we send QoS negotiation parameters? */
+ if (qos) {
+ ret = irlap_insert_qos_negotiation_params(self, tx_skb);
+ if (ret < 0) {
+ dev_kfree_skb(tx_skb);
+ return;
+ }
+ }
+
+ irlap_queue_xmit(self, tx_skb);
+}
+
+
+/*
+ * Function irlap_send_dm_frame (void)
+ *
+ * Send disconnected mode (DM) frame
+ *
+ */
+void irlap_send_dm_frame( struct irlap_cb *self)
+{
+ struct sk_buff *tx_skb = NULL;
+ __u8 *frame;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+ tx_skb = dev_alloc_skb(32);
+ if (!tx_skb)
+ return;
+
+ frame = skb_put(tx_skb, 2);
+
+ if (self->state == LAP_NDM)
+ frame[0] = CBROADCAST;
+ else
+ frame[0] = self->caddr;
+
+ frame[1] = DM_RSP | PF_BIT;
+
+ irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_send_disc_frame (void)
+ *
+ * Send disconnect (DISC) frame
+ *
+ */
+void irlap_send_disc_frame(struct irlap_cb *self)
+{
+ struct sk_buff *tx_skb = NULL;
+ __u8 *frame;
+
+ IRDA_DEBUG(3, "%s()\n", __FUNCTION__);
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+ tx_skb = dev_alloc_skb(16);
+ if (!tx_skb)
+ return;
+
+ frame = skb_put(tx_skb, 2);
+
+ frame[0] = self->caddr | CMD_FRAME;
+ frame[1] = DISC_CMD | PF_BIT;
+
+ irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_send_discovery_xid_frame (S, s, command)
+ *
+ * Build and transmit a XID (eXchange station IDentifier) discovery
+ * frame.
+ */
+void irlap_send_discovery_xid_frame(struct irlap_cb *self, int S, __u8 s,
+ __u8 command, discovery_t *discovery)
+{
+ struct sk_buff *tx_skb = NULL;
+ struct xid_frame *frame;
+ __u32 bcast = BROADCAST;
+ __u8 *info;
+
+ IRDA_DEBUG(4, "%s(), s=%d, S=%d, command=%d\n", __FUNCTION__,
+ s, S, command);
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+ IRDA_ASSERT(discovery != NULL, return;);
+
+ tx_skb = dev_alloc_skb(64);
+ if (!tx_skb)
+ return;
+
+ skb_put(tx_skb, 14);
+ frame = (struct xid_frame *) tx_skb->data;
+
+ if (command) {
+ frame->caddr = CBROADCAST | CMD_FRAME;
+ frame->control = XID_CMD | PF_BIT;
+ } else {
+ frame->caddr = CBROADCAST;
+ frame->control = XID_RSP | PF_BIT;
+ }
+ frame->ident = XID_FORMAT;
+
+ frame->saddr = cpu_to_le32(self->saddr);
+
+ if (command)
+ frame->daddr = cpu_to_le32(bcast);
+ else
+ frame->daddr = cpu_to_le32(discovery->data.daddr);
+
+ switch (S) {
+ case 1:
+ frame->flags = 0x00;
+ break;
+ case 6:
+ frame->flags = 0x01;
+ break;
+ case 8:
+ frame->flags = 0x02;
+ break;
+ case 16:
+ frame->flags = 0x03;
+ break;
+ default:
+ frame->flags = 0x02;
+ break;
+ }
+
+ frame->slotnr = s;
+ frame->version = 0x00;
+
+ /*
+ * Provide info for final slot only in commands, and for all
+ * responses. Send the second byte of the hint only if the
+ * EXTENSION bit is set in the first byte.
+ */
+ if (!command || (frame->slotnr == 0xff)) {
+ int len;
+
+ if (discovery->data.hints[0] & HINT_EXTENSION) {
+ info = skb_put(tx_skb, 2);
+ info[0] = discovery->data.hints[0];
+ info[1] = discovery->data.hints[1];
+ } else {
+ info = skb_put(tx_skb, 1);
+ info[0] = discovery->data.hints[0];
+ }
+ info = skb_put(tx_skb, 1);
+ info[0] = discovery->data.charset;
+
+ len = IRDA_MIN(discovery->name_len, skb_tailroom(tx_skb));
+ info = skb_put(tx_skb, len);
+ memcpy(info, discovery->data.info, len);
+ }
+ irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_discovery_xid_rsp (skb, info)
+ *
+ * Received a XID discovery response
+ *
+ */
+static void irlap_recv_discovery_xid_rsp(struct irlap_cb *self,
+ struct sk_buff *skb,
+ struct irlap_info *info)
+{
+ struct xid_frame *xid;
+ discovery_t *discovery = NULL;
+ __u8 *discovery_info;
+ char *text;
+
+ IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+ if (!pskb_may_pull(skb, sizeof(struct xid_frame))) {
+ IRDA_ERROR("%s: frame to short!\n", __FUNCTION__);
+ return;
+ }
+
+ xid = (struct xid_frame *) skb->data;
+
+ info->daddr = le32_to_cpu(xid->saddr);
+ info->saddr = le32_to_cpu(xid->daddr);
+
+ /* Make sure frame is addressed to us */
+ if ((info->saddr != self->saddr) && (info->saddr != BROADCAST)) {
+ IRDA_DEBUG(0, "%s(), frame is not addressed to us!\n",
+ __FUNCTION__);
+ return;
+ }
+
+ if ((discovery = kmalloc(sizeof(discovery_t), GFP_ATOMIC)) == NULL) {
+ IRDA_WARNING("%s: kmalloc failed!\n", __FUNCTION__);
+ return;
+ }
+ memset(discovery, 0, sizeof(discovery_t));
+
+ discovery->data.daddr = info->daddr;
+ discovery->data.saddr = self->saddr;
+ discovery->timestamp = jiffies;
+
+ IRDA_DEBUG(4, "%s(), daddr=%08x\n", __FUNCTION__,
+ discovery->data.daddr);
+
+ discovery_info = skb_pull(skb, sizeof(struct xid_frame));
+
+ /* Get info returned from peer */
+ discovery->data.hints[0] = discovery_info[0];
+ if (discovery_info[0] & HINT_EXTENSION) {
+ IRDA_DEBUG(4, "EXTENSION\n");
+ discovery->data.hints[1] = discovery_info[1];
+ discovery->data.charset = discovery_info[2];
+ text = (char *) &discovery_info[3];
+ } else {
+ discovery->data.hints[1] = 0;
+ discovery->data.charset = discovery_info[1];
+ text = (char *) &discovery_info[2];
+ }
+ /*
+ * Terminate info string, should be safe since this is where the
+ * FCS bytes resides.
+ */
+ skb->data[skb->len] = '\0';
+ strncpy(discovery->data.info, text, NICKNAME_MAX_LEN);
+ discovery->name_len = strlen(discovery->data.info);
+
+ info->discovery = discovery;
+
+ irlap_do_event(self, RECV_DISCOVERY_XID_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_discovery_xid_cmd (skb, info)
+ *
+ * Received a XID discovery command
+ *
+ */
+static void irlap_recv_discovery_xid_cmd(struct irlap_cb *self,
+ struct sk_buff *skb,
+ struct irlap_info *info)
+{
+ struct xid_frame *xid;
+ discovery_t *discovery = NULL;
+ __u8 *discovery_info;
+ char *text;
+
+ if (!pskb_may_pull(skb, sizeof(struct xid_frame))) {
+ IRDA_ERROR("%s: frame to short!\n", __FUNCTION__);
+ return;
+ }
+
+ xid = (struct xid_frame *) skb->data;
+
+ info->daddr = le32_to_cpu(xid->saddr);
+ info->saddr = le32_to_cpu(xid->daddr);
+
+ /* Make sure frame is addressed to us */
+ if ((info->saddr != self->saddr) && (info->saddr != BROADCAST)) {
+ IRDA_DEBUG(0, "%s(), frame is not addressed to us!\n",
+ __FUNCTION__);
+ return;
+ }
+
+ switch (xid->flags & 0x03) {
+ case 0x00:
+ info->S = 1;
+ break;
+ case 0x01:
+ info->S = 6;
+ break;
+ case 0x02:
+ info->S = 8;
+ break;
+ case 0x03:
+ info->S = 16;
+ break;
+ default:
+ /* Error!! */
+ return;
+ }
+ info->s = xid->slotnr;
+
+ discovery_info = skb_pull(skb, sizeof(struct xid_frame));
+
+ /*
+ * Check if last frame
+ */
+ if (info->s == 0xff) {
+ /* Check if things are sane at this point... */
+ if((discovery_info == NULL) ||
+ !pskb_may_pull(skb, 3)) {
+ IRDA_ERROR("%s: discovery frame to short!\n",
+ __FUNCTION__);
+ return;
+ }
+
+ /*
+ * We now have some discovery info to deliver!
+ */
+ discovery = kmalloc(sizeof(discovery_t), GFP_ATOMIC);
+ if (!discovery) {
+ IRDA_WARNING("%s: unable to malloc!\n", __FUNCTION__);
+ return;
+ }
+
+ discovery->data.daddr = info->daddr;
+ discovery->data.saddr = self->saddr;
+ discovery->timestamp = jiffies;
+
+ discovery->data.hints[0] = discovery_info[0];
+ if (discovery_info[0] & HINT_EXTENSION) {
+ discovery->data.hints[1] = discovery_info[1];
+ discovery->data.charset = discovery_info[2];
+ text = (char *) &discovery_info[3];
+ } else {
+ discovery->data.hints[1] = 0;
+ discovery->data.charset = discovery_info[1];
+ text = (char *) &discovery_info[2];
+ }
+ /*
+ * Terminate string, should be safe since this is where the
+ * FCS bytes resides.
+ */
+ skb->data[skb->len] = '\0';
+ strncpy(discovery->data.info, text, NICKNAME_MAX_LEN);
+ discovery->name_len = strlen(discovery->data.info);
+
+ info->discovery = discovery;
+ } else
+ info->discovery = NULL;
+
+ irlap_do_event(self, RECV_DISCOVERY_XID_CMD, skb, info);
+}
+
+/*
+ * Function irlap_send_rr_frame (self, command)
+ *
+ * Build and transmit RR (Receive Ready) frame. Notice that it is currently
+ * only possible to send RR frames with the poll bit set.
+ */
+void irlap_send_rr_frame(struct irlap_cb *self, int command)
+{
+ struct sk_buff *tx_skb;
+ __u8 *frame;
+
+ tx_skb = dev_alloc_skb(16);
+ if (!tx_skb)
+ return;
+
+ frame = skb_put(tx_skb, 2);
+
+ frame[0] = self->caddr;
+ frame[0] |= (command) ? CMD_FRAME : 0;
+
+ frame[1] = RR | PF_BIT | (self->vr << 5);
+
+ irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_send_rd_frame (self)
+ *
+ * Request disconnect. Used by a secondary station to request the
+ * disconnection of the link.
+ */
+void irlap_send_rd_frame(struct irlap_cb *self)
+{
+ struct sk_buff *tx_skb;
+ __u8 *frame;
+
+ tx_skb = dev_alloc_skb(16);
+ if (!tx_skb)
+ return;
+
+ frame = skb_put(tx_skb, 2);
+
+ frame[0] = self->caddr;
+ frame[1] = RD_RSP | PF_BIT;
+
+ irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_rr_frame (skb, info)
+ *
+ * Received RR (Receive Ready) frame from peer station, no harm in
+ * making it inline since its called only from one single place
+ * (irlap_driver_rcv).
+ */
+static inline void irlap_recv_rr_frame(struct irlap_cb *self,
+ struct sk_buff *skb,
+ struct irlap_info *info, int command)
+{
+ info->nr = skb->data[1] >> 5;
+
+ /* Check if this is a command or a response frame */
+ if (command)
+ irlap_do_event(self, RECV_RR_CMD, skb, info);
+ else
+ irlap_do_event(self, RECV_RR_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_rnr_frame (self, skb, info)
+ *
+ * Received RNR (Receive Not Ready) frame from peer station
+ *
+ */
+static void irlap_recv_rnr_frame(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info, int command)
+{
+ info->nr = skb->data[1] >> 5;
+
+ IRDA_DEBUG(4, "%s(), nr=%d, %ld\n", __FUNCTION__, info->nr, jiffies);
+
+ if (command)
+ irlap_do_event(self, RECV_RNR_CMD, skb, info);
+ else
+ irlap_do_event(self, RECV_RNR_RSP, skb, info);
+}
+
+static void irlap_recv_rej_frame(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info, int command)
+{
+ IRDA_DEBUG(0, "%s()\n", __FUNCTION__);
+
+ info->nr = skb->data[1] >> 5;
+
+ /* Check if this is a command or a response frame */
+ if (command)
+ irlap_do_event(self, RECV_REJ_CMD, skb, info);
+ else
+ irlap_do_event(self, RECV_REJ_RSP, skb, info);
+}
+
+static void irlap_recv_srej_frame(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info, int command)
+{
+ IRDA_DEBUG(0, "%s()\n", __FUNCTION__);
+
+ info->nr = skb->data[1] >> 5;
+
+ /* Check if this is a command or a response frame */
+ if (command)
+ irlap_do_event(self, RECV_SREJ_CMD, skb, info);
+ else
+ irlap_do_event(self, RECV_SREJ_RSP, skb, info);
+}
+
+static void irlap_recv_disc_frame(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info, int command)
+{
+ IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
+
+ /* Check if this is a command or a response frame */
+ if (command)
+ irlap_do_event(self, RECV_DISC_CMD, skb, info);
+ else
+ irlap_do_event(self, RECV_RD_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_ua_frame (skb, frame)
+ *
+ * Received UA (Unnumbered Acknowledgement) frame
+ *
+ */
+static inline void irlap_recv_ua_frame(struct irlap_cb *self,
+ struct sk_buff *skb,
+ struct irlap_info *info)
+{
+ irlap_do_event(self, RECV_UA_RSP, skb, info);
+}
+
+/*
+ * Function irlap_send_data_primary(self, skb)
+ *
+ * Send I-frames as the primary station but without the poll bit set
+ *
+ */
+void irlap_send_data_primary(struct irlap_cb *self, struct sk_buff *skb)
+{
+ struct sk_buff *tx_skb;
+
+ if (skb->data[1] == I_FRAME) {
+
+ /*
+ * Insert frame sequence number (Vs) in control field before
+ * inserting into transmit window queue.
+ */
+ skb->data[1] = I_FRAME | (self->vs << 1);
+
+ /*
+ * Insert frame in store, in case of retransmissions
+ * Increase skb reference count, see irlap_do_event()
+ */
+ skb_get(skb);
+ skb_queue_tail(&self->wx_list, skb);
+
+ /* Copy buffer */
+ tx_skb = skb_clone(skb, GFP_ATOMIC);
+ if (tx_skb == NULL) {
+ return;
+ }
+
+ self->vs = (self->vs + 1) % 8;
+ self->ack_required = FALSE;
+ self->window -= 1;
+
+ irlap_send_i_frame( self, tx_skb, CMD_FRAME);
+ } else {
+ IRDA_DEBUG(4, "%s(), sending unreliable frame\n", __FUNCTION__);
+ irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
+ self->window -= 1;
+ }
+}
+/*
+ * Function irlap_send_data_primary_poll (self, skb)
+ *
+ * Send I(nformation) frame as primary with poll bit set
+ */
+void irlap_send_data_primary_poll(struct irlap_cb *self, struct sk_buff *skb)
+{
+ struct sk_buff *tx_skb;
+ int transmission_time;
+
+ /* Stop P timer */
+ del_timer(&self->poll_timer);
+
+ /* Is this reliable or unreliable data? */
+ if (skb->data[1] == I_FRAME) {
+
+ /*
+ * Insert frame sequence number (Vs) in control field before
+ * inserting into transmit window queue.
+ */
+ skb->data[1] = I_FRAME | (self->vs << 1);
+
+ /*
+ * Insert frame in store, in case of retransmissions
+ * Increase skb reference count, see irlap_do_event()
+ */
+ skb_get(skb);
+ skb_queue_tail(&self->wx_list, skb);
+
+ /* Copy buffer */
+ tx_skb = skb_clone(skb, GFP_ATOMIC);
+ if (tx_skb == NULL) {
+ return;
+ }
+
+ /*
+ * Set poll bit if necessary. We do this to the copied
+ * skb, since retransmitted need to set or clear the poll
+ * bit depending on when they are sent.
+ */
+ tx_skb->data[1] |= PF_BIT;
+
+ self->vs = (self->vs + 1) % 8;
+ self->ack_required = FALSE;
+
+ irlap_send_i_frame(self, tx_skb, CMD_FRAME);
+ } else {
+ IRDA_DEBUG(4, "%s(), sending unreliable frame\n", __FUNCTION__);
+
+ if (self->ack_required) {
+ irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
+ irlap_send_rr_frame(self, CMD_FRAME);
+ self->ack_required = FALSE;
+ } else {
+ skb->data[1] |= PF_BIT;
+ irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
+ }
+ }
+
+ /* How much time we took for transmission of all frames.
+ * We don't know, so let assume we used the full window. Jean II */
+ transmission_time = self->final_timeout;
+
+ /* Reset parameter so that we can fill next window */
+ self->window = self->window_size;
+
+#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
+ /* Remove what we have not used. Just do a prorata of the
+ * bytes left in window to window capacity.
+ * See max_line_capacities[][] in qos.c for details. Jean II */
+ transmission_time -= (self->final_timeout * self->bytes_left
+ / self->line_capacity);
+ IRDA_DEBUG(4, "%s() adjusting transmission_time : ft=%d, bl=%d, lc=%d -> tt=%d\n", __FUNCTION__, self->final_timeout, self->bytes_left, self->line_capacity, transmission_time);
+
+ /* We are allowed to transmit a maximum number of bytes again. */
+ self->bytes_left = self->line_capacity;
+#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
+
+ /*
+ * The network layer has a intermediate buffer between IrLAP
+ * and the IrDA driver which can contain 8 frames. So, even
+ * though IrLAP is currently sending the *last* frame of the
+ * tx-window, the driver most likely has only just started
+ * sending the *first* frame of the same tx-window.
+ * I.e. we are always at the very begining of or Tx window.
+ * Now, we are supposed to set the final timer from the end
+ * of our tx-window to let the other peer reply. So, we need
+ * to add extra time to compensate for the fact that we
+ * are really at the start of tx-window, otherwise the final timer
+ * might expire before he can answer...
+ * Jean II
+ */
+ irlap_start_final_timer(self, self->final_timeout + transmission_time);
+
+ /*
+ * The clever amongst you might ask why we do this adjustement
+ * only here, and not in all the other cases in irlap_event.c.
+ * In all those other case, we only send a very short management
+ * frame (few bytes), so the adjustement would be lost in the
+ * noise...
+ * The exception of course is irlap_resend_rejected_frame().
+ * Jean II */
+}
+
+/*
+ * Function irlap_send_data_secondary_final (self, skb)
+ *
+ * Send I(nformation) frame as secondary with final bit set
+ *
+ */
+void irlap_send_data_secondary_final(struct irlap_cb *self,
+ struct sk_buff *skb)
+{
+ struct sk_buff *tx_skb = NULL;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+ IRDA_ASSERT(skb != NULL, return;);
+
+ /* Is this reliable or unreliable data? */
+ if (skb->data[1] == I_FRAME) {
+
+ /*
+ * Insert frame sequence number (Vs) in control field before
+ * inserting into transmit window queue.
+ */
+ skb->data[1] = I_FRAME | (self->vs << 1);
+
+ /*
+ * Insert frame in store, in case of retransmissions
+ * Increase skb reference count, see irlap_do_event()
+ */
+ skb_get(skb);
+ skb_queue_tail(&self->wx_list, skb);
+
+ tx_skb = skb_clone(skb, GFP_ATOMIC);
+ if (tx_skb == NULL) {
+ return;
+ }
+
+ tx_skb->data[1] |= PF_BIT;
+
+ self->vs = (self->vs + 1) % 8;
+ self->ack_required = FALSE;
+
+ irlap_send_i_frame(self, tx_skb, RSP_FRAME);
+ } else {
+ if (self->ack_required) {
+ irlap_send_ui_frame(self, skb_get(skb), self->caddr, RSP_FRAME);
+ irlap_send_rr_frame(self, RSP_FRAME);
+ self->ack_required = FALSE;
+ } else {
+ skb->data[1] |= PF_BIT;
+ irlap_send_ui_frame(self, skb_get(skb), self->caddr, RSP_FRAME);
+ }
+ }
+
+ self->window = self->window_size;
+#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
+ /* We are allowed to transmit a maximum number of bytes again. */
+ self->bytes_left = self->line_capacity;
+#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
+
+ irlap_start_wd_timer(self, self->wd_timeout);
+}
+
+/*
+ * Function irlap_send_data_secondary (self, skb)
+ *
+ * Send I(nformation) frame as secondary without final bit set
+ *
+ */
+void irlap_send_data_secondary(struct irlap_cb *self, struct sk_buff *skb)
+{
+ struct sk_buff *tx_skb = NULL;
+
+ /* Is this reliable or unreliable data? */
+ if (skb->data[1] == I_FRAME) {
+
+ /*
+ * Insert frame sequence number (Vs) in control field before
+ * inserting into transmit window queue.
+ */
+ skb->data[1] = I_FRAME | (self->vs << 1);
+
+ /*
+ * Insert frame in store, in case of retransmissions
+ * Increase skb reference count, see irlap_do_event()
+ */
+ skb_get(skb);
+ skb_queue_tail(&self->wx_list, skb);
+
+ tx_skb = skb_clone(skb, GFP_ATOMIC);
+ if (tx_skb == NULL) {
+ return;
+ }
+
+ self->vs = (self->vs + 1) % 8;
+ self->ack_required = FALSE;
+ self->window -= 1;
+
+ irlap_send_i_frame(self, tx_skb, RSP_FRAME);
+ } else {
+ irlap_send_ui_frame(self, skb_get(skb), self->caddr, RSP_FRAME);
+ self->window -= 1;
+ }
+}
+
+/*
+ * Function irlap_resend_rejected_frames (nr)
+ *
+ * Resend frames which has not been acknowledged. Should be safe to
+ * traverse the list without locking it since this function will only be
+ * called from interrupt context (BH)
+ */
+void irlap_resend_rejected_frames(struct irlap_cb *self, int command)
+{
+ struct sk_buff *tx_skb;
+ struct sk_buff *skb;
+ int count;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+ /* Initialize variables */
+ count = skb_queue_len(&self->wx_list);
+
+ /* Resend unacknowledged frame(s) */
+ skb = skb_peek(&self->wx_list);
+ while (skb != NULL) {
+ irlap_wait_min_turn_around(self, &self->qos_tx);
+
+ /* We copy the skb to be retransmitted since we will have to
+ * modify it. Cloning will confuse packet sniffers
+ */
+ /* tx_skb = skb_clone( skb, GFP_ATOMIC); */
+ tx_skb = skb_copy(skb, GFP_ATOMIC);
+ if (!tx_skb) {
+ IRDA_DEBUG(0, "%s(), unable to copy\n", __FUNCTION__);
+ return;
+ }
+ /* Unlink tx_skb from list */
+ tx_skb->next = tx_skb->prev = NULL;
+ tx_skb->list = NULL;
+
+ /* Clear old Nr field + poll bit */
+ tx_skb->data[1] &= 0x0f;
+
+ /*
+ * Set poll bit on the last frame retransmitted
+ */
+ if (count-- == 1)
+ tx_skb->data[1] |= PF_BIT; /* Set p/f bit */
+ else
+ tx_skb->data[1] &= ~PF_BIT; /* Clear p/f bit */
+
+ irlap_send_i_frame(self, tx_skb, command);
+
+ /*
+ * If our skb is the last buffer in the list, then
+ * we are finished, if not, move to the next sk-buffer
+ */
+ if (skb == skb_peek_tail(&self->wx_list))
+ skb = NULL;
+ else
+ skb = skb->next;
+ }
+#if 0 /* Not yet */
+ /*
+ * We can now fill the window with additional data frames
+ */
+ while (skb_queue_len( &self->txq) > 0) {
+
+ IRDA_DEBUG(0, "%s(), sending additional frames!\n", __FUNCTION__);
+ if ((skb_queue_len( &self->txq) > 0) &&
+ (self->window > 0)) {
+ skb = skb_dequeue( &self->txq);
+ IRDA_ASSERT(skb != NULL, return;);
+
+ /*
+ * If send window > 1 then send frame with pf
+ * bit cleared
+ */
+ if ((self->window > 1) &&
+ skb_queue_len(&self->txq) > 0)
+ {
+ irlap_send_data_primary(self, skb);
+ } else {
+ irlap_send_data_primary_poll(self, skb);
+ }
+ kfree_skb(skb);
+ }
+ }
+#endif
+}
+
+void irlap_resend_rejected_frame(struct irlap_cb *self, int command)
+{
+ struct sk_buff *tx_skb;
+ struct sk_buff *skb;
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+
+ /* Resend unacknowledged frame(s) */
+ skb = skb_peek(&self->wx_list);
+ if (skb != NULL) {
+ irlap_wait_min_turn_around(self, &self->qos_tx);
+
+ /* We copy the skb to be retransmitted since we will have to
+ * modify it. Cloning will confuse packet sniffers
+ */
+ /* tx_skb = skb_clone( skb, GFP_ATOMIC); */
+ tx_skb = skb_copy(skb, GFP_ATOMIC);
+ if (!tx_skb) {
+ IRDA_DEBUG(0, "%s(), unable to copy\n", __FUNCTION__);
+ return;
+ }
+ /* Unlink tx_skb from list */
+ tx_skb->next = tx_skb->prev = NULL;
+ tx_skb->list = NULL;
+
+ /* Clear old Nr field + poll bit */
+ tx_skb->data[1] &= 0x0f;
+
+ /* Set poll/final bit */
+ tx_skb->data[1] |= PF_BIT; /* Set p/f bit */
+
+ irlap_send_i_frame(self, tx_skb, command);
+ }
+}
+
+/*
+ * Function irlap_send_ui_frame (self, skb, command)
+ *
+ * Contruct and transmit an Unnumbered Information (UI) frame
+ *
+ */
+void irlap_send_ui_frame(struct irlap_cb *self, struct sk_buff *skb,
+ __u8 caddr, int command)
+{
+ IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+ IRDA_ASSERT(skb != NULL, return;);
+
+ /* Insert connection address */
+ skb->data[0] = caddr | ((command) ? CMD_FRAME : 0);
+
+ irlap_queue_xmit(self, skb);
+}
+
+/*
+ * Function irlap_send_i_frame (skb)
+ *
+ * Contruct and transmit Information (I) frame
+ */
+static void irlap_send_i_frame(struct irlap_cb *self, struct sk_buff *skb,
+ int command)
+{
+ /* Insert connection address */
+ skb->data[0] = self->caddr;
+ skb->data[0] |= (command) ? CMD_FRAME : 0;
+
+ /* Insert next to receive (Vr) */
+ skb->data[1] |= (self->vr << 5); /* insert nr */
+
+ irlap_queue_xmit(self, skb);
+}
+
+/*
+ * Function irlap_recv_i_frame (skb, frame)
+ *
+ * Receive and parse an I (Information) frame, no harm in making it inline
+ * since it's called only from one single place (irlap_driver_rcv).
+ */
+static inline void irlap_recv_i_frame(struct irlap_cb *self,
+ struct sk_buff *skb,
+ struct irlap_info *info, int command)
+{
+ info->nr = skb->data[1] >> 5; /* Next to receive */
+ info->pf = skb->data[1] & PF_BIT; /* Final bit */
+ info->ns = (skb->data[1] >> 1) & 0x07; /* Next to send */
+
+ /* Check if this is a command or a response frame */
+ if (command)
+ irlap_do_event(self, RECV_I_CMD, skb, info);
+ else
+ irlap_do_event(self, RECV_I_RSP, skb, info);
+}
+
+/*
+ * Function irlap_recv_ui_frame (self, skb, info)
+ *
+ * Receive and parse an Unnumbered Information (UI) frame
+ *
+ */
+static void irlap_recv_ui_frame(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info)
+{
+ IRDA_DEBUG( 4, "%s()\n", __FUNCTION__);
+
+ info->pf = skb->data[1] & PF_BIT; /* Final bit */
+
+ irlap_do_event(self, RECV_UI_FRAME, skb, info);
+}
+
+/*
+ * Function irlap_recv_frmr_frame (skb, frame)
+ *
+ * Received Frame Reject response.
+ *
+ */
+static void irlap_recv_frmr_frame(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info)
+{
+ __u8 *frame;
+ int w, x, y, z;
+
+ IRDA_DEBUG(0, "%s()\n", __FUNCTION__);
+
+ IRDA_ASSERT(self != NULL, return;);
+ IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
+ IRDA_ASSERT(skb != NULL, return;);
+ IRDA_ASSERT(info != NULL, return;);
+
+ if (!pskb_may_pull(skb, 4)) {
+ IRDA_ERROR("%s: frame to short!\n", __FUNCTION__);
+ return;
+ }
+
+ frame = skb->data;
+
+ info->nr = frame[2] >> 5; /* Next to receive */
+ info->pf = frame[2] & PF_BIT; /* Final bit */
+ info->ns = (frame[2] >> 1) & 0x07; /* Next to send */
+
+ w = frame[3] & 0x01;
+ x = frame[3] & 0x02;
+ y = frame[3] & 0x04;
+ z = frame[3] & 0x08;
+
+ if (w) {
+ IRDA_DEBUG(0, "Rejected control field is undefined or not "
+ "implemented.\n");
+ }
+ if (x) {
+ IRDA_DEBUG(0, "Rejected control field was invalid because it "
+ "contained a non permitted I field.\n");
+ }
+ if (y) {
+ IRDA_DEBUG(0, "Received I field exceeded the maximum negotiated "
+ "for the existing connection or exceeded the maximum "
+ "this station supports if no connection exists.\n");
+ }
+ if (z) {
+ IRDA_DEBUG(0, "Rejected control field control field contained an "
+ "invalid Nr count.\n");
+ }
+ irlap_do_event(self, RECV_FRMR_RSP, skb, info);
+}
+
+/*
+ * Function irlap_send_test_frame (self, daddr)
+ *
+ * Send a test frame response
+ *
+ */
+void irlap_send_test_frame(struct irlap_cb *self, __u8 caddr, __u32 daddr,
+ struct sk_buff *cmd)
+{
+ struct sk_buff *tx_skb;
+ struct test_frame *frame;
+ __u8 *info;
+
+ tx_skb = dev_alloc_skb(cmd->len+sizeof(struct test_frame));
+ if (!tx_skb)
+ return;
+
+ /* Broadcast frames must include saddr and daddr fields */
+ if (caddr == CBROADCAST) {
+ frame = (struct test_frame *)
+ skb_put(tx_skb, sizeof(struct test_frame));
+
+ /* Insert the swapped addresses */
+ frame->saddr = cpu_to_le32(self->saddr);
+ frame->daddr = cpu_to_le32(daddr);
+ } else
+ frame = (struct test_frame *) skb_put(tx_skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);
+
+ frame->caddr = caddr;
+ frame->control = TEST_RSP | PF_BIT;
+
+ /* Copy info */
+ info = skb_put(tx_skb, cmd->len);
+ memcpy(info, cmd->data, cmd->len);
+
+ /* Return to sender */
+ irlap_wait_min_turn_around(self, &self->qos_tx);
+ irlap_queue_xmit(self, tx_skb);
+}
+
+/*
+ * Function irlap_recv_test_frame (self, skb)
+ *
+ * Receive a test frame
+ *
+ */
+static void irlap_recv_test_frame(struct irlap_cb *self, struct sk_buff *skb,
+ struct irlap_info *info, int command)
+{
+ struct test_frame *frame;
+
+ IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
+
+ if (!pskb_may_pull(skb, sizeof(*frame))) {
+ IRDA_ERROR("%s: frame to short!\n", __FUNCTION__);
+ return;
+ }
+ frame = (struct test_frame *) skb->data;
+
+ /* Broadcast frames must carry saddr and daddr fields */
+ if (info->caddr == CBROADCAST) {
+ if (skb->len < sizeof(struct test_frame)) {
+ IRDA_DEBUG(0, "%s() test frame to short!\n",
+ __FUNCTION__);
+ return;
+ }
+
+ /* Read and swap addresses */
+ info->daddr = le32_to_cpu(frame->saddr);
+ info->saddr = le32_to_cpu(frame->daddr);
+
+ /* Make sure frame is addressed to us */
+ if ((info->saddr != self->saddr) &&
+ (info->saddr != BROADCAST)) {
+ return;
+ }
+ }
+
+ if (command)
+ irlap_do_event(self, RECV_TEST_CMD, skb, info);
+ else
+ irlap_do_event(self, RECV_TEST_RSP, skb, info);
+}
+
+/*
+ * Function irlap_driver_rcv (skb, netdev, ptype)
+ *
+ * Called when a frame is received. Dispatches the right receive function
+ * for processing of the frame.
+ *
+ * Note on skb management :
+ * After calling the higher layers of the IrDA stack, we always
+ * kfree() the skb, which drop the reference count (and potentially
+ * destroy it).
+ * If a higher layer of the stack want to keep the skb around (to put
+ * in a queue or pass it to the higher layer), it will need to use
+ * skb_get() to keep a reference on it. This is usually done at the
+ * LMP level in irlmp.c.
+ * Jean II
+ */
+int irlap_driver_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *ptype)
+{
+ struct irlap_info info;
+ struct irlap_cb *self;
+ int command;
+ __u8 control;
+
+ /* FIXME: should we get our own field? */
+ self = (struct irlap_cb *) dev->atalk_ptr;
+
+ /* If the net device is down, then IrLAP is gone! */
+ if (!self || self->magic != LAP_MAGIC) {
+ dev_kfree_skb(skb);
+ return -1;
+ }
+
+ /* We are no longer an "old" protocol, so we need to handle
+ * share and non linear skbs. This should never happen, so
+ * we don't need to be clever about it. Jean II */
+ if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
+ IRDA_ERROR("%s: can't clone shared skb!\n", __FUNCTION__);
+ dev_kfree_skb(skb);
+ return -1;
+ }
+
+ /* Check if frame is large enough for parsing */
+ if (!pskb_may_pull(skb, 2)) {
+ IRDA_ERROR("%s: frame to short!\n", __FUNCTION__);
+ dev_kfree_skb(skb);
+ return -1;
+ }
+
+ command = skb->data[0] & CMD_FRAME;
+ info.caddr = skb->data[0] & CBROADCAST;
+
+ info.pf = skb->data[1] & PF_BIT;
+ info.control = skb->data[1] & ~PF_BIT; /* Mask away poll/final bit */
+
+ control = info.control;
+
+ /* First we check if this frame has a valid connection address */
+ if ((info.caddr != self->caddr) && (info.caddr != CBROADCAST)) {
+ IRDA_DEBUG(0, "%s(), wrong connection address!\n",
+ __FUNCTION__);
+ goto out;
+ }
+ /*
+ * Optimize for the common case and check if the frame is an
+ * I(nformation) frame. Only I-frames have bit 0 set to 0
+ */
+ if (~control & 0x01) {
+ irlap_recv_i_frame(self, skb, &info, command);
+ goto out;
+ }
+ /*
+ * We now check is the frame is an S(upervisory) frame. Only
+ * S-frames have bit 0 set to 1 and bit 1 set to 0
+ */
+ if (~control & 0x02) {
+ /*
+ * Received S(upervisory) frame, check which frame type it is
+ * only the first nibble is of interest
+ */
+ switch (control & 0x0f) {
+ case RR:
+ irlap_recv_rr_frame(self, skb, &info, command);
+ break;
+ case RNR:
+ irlap_recv_rnr_frame(self, skb, &info, command);
+ break;
+ case REJ:
+ irlap_recv_rej_frame(self, skb, &info, command);
+ break;
+ case SREJ:
+ irlap_recv_srej_frame(self, skb, &info, command);
+ break;
+ default:
+ IRDA_WARNING("%s: Unknown S-frame %02x received!\n",
+ __FUNCTION__, info.control);
+ break;
+ }
+ goto out;
+ }
+ /*
+ * This must be a C(ontrol) frame
+ */
+ switch (control) {
+ case XID_RSP:
+ irlap_recv_discovery_xid_rsp(self, skb, &info);
+ break;
+ case XID_CMD:
+ irlap_recv_discovery_xid_cmd(self, skb, &info);
+ break;
+ case SNRM_CMD:
+ irlap_recv_snrm_cmd(self, skb, &info);
+ break;
+ case DM_RSP:
+ irlap_do_event(self, RECV_DM_RSP, skb, &info);
+ break;
+ case DISC_CMD: /* And RD_RSP since they have the same value */
+ irlap_recv_disc_frame(self, skb, &info, command);
+ break;
+ case TEST_CMD:
+ irlap_recv_test_frame(self, skb, &info, command);
+ break;
+ case UA_RSP:
+ irlap_recv_ua_frame(self, skb, &info);
+ break;
+ case FRMR_RSP:
+ irlap_recv_frmr_frame(self, skb, &info);
+ break;
+ case UI_FRAME:
+ irlap_recv_ui_frame(self, skb, &info);
+ break;
+ default:
+ IRDA_WARNING("%s: Unknown frame %02x received!\n",
+ __FUNCTION__, info.control);
+ break;
+ }
+out:
+ /* Always drop our reference on the skb */
+ dev_kfree_skb(skb);
+ return 0;
+}
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