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/*********************************************************************
*
* 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) 2000-2001 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>
/*
* 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 *skb;
struct snrm_frame *frame;
int ret;
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
/* Allocate frame */
skb = dev_alloc_skb(64);
if (!skb)
return;
frame = (struct snrm_frame *) skb_put(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(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, skb);
if (ret < 0) {
dev_kfree_skb(skb);
return;
}
}
irlap_queue_xmit(self, 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;
frame = (struct snrm_frame *) skb->data;
if (skb->len >= sizeof(struct snrm_frame)) {
/* Copy the new connection address */
info->caddr = frame->ncaddr;
/* Check if the new connection address is valid */
if ((info->caddr == 0x00) || (info->caddr == 0xfe)) {
IRDA_DEBUG(3, __FUNCTION__
"(), invalid connection address!\n");
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, __FUNCTION__ "(), not addressed to us!\n");
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 *skb;
struct ua_frame *frame;
int ret;
IRDA_DEBUG(2, __FUNCTION__ "() <%ld>\n", jiffies);
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
skb = NULL;
/* Allocate frame */
skb = dev_alloc_skb(64);
if (!skb)
return;
frame = (struct ua_frame *) skb_put(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, skb);
if (ret < 0) {
dev_kfree_skb(skb);
return;
}
}
irlap_queue_xmit(self, skb);
}
/*
* Function irlap_send_dm_frame (void)
*
* Send disconnected mode (DM) frame
*
*/
void irlap_send_dm_frame( struct irlap_cb *self)
{
struct sk_buff *skb = NULL;
__u8 *frame;
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
skb = dev_alloc_skb(32);
if (!skb)
return;
frame = skb_put( 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, skb);
}
/*
* Function irlap_send_disc_frame (void)
*
* Send disconnect (DISC) frame
*
*/
void irlap_send_disc_frame(struct irlap_cb *self)
{
struct sk_buff *skb = NULL;
__u8 *frame;
IRDA_DEBUG(3, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
skb = dev_alloc_skb(16);
if (!skb)
return;
frame = skb_put(skb, 2);
frame[0] = self->caddr | CMD_FRAME;
frame[1] = DISC_CMD | PF_BIT;
irlap_queue_xmit(self, 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 *skb = NULL;
struct xid_frame *frame;
__u32 bcast = BROADCAST;
__u8 *info;
IRDA_DEBUG(4, __FUNCTION__ "(), s=%d, S=%d, command=%d\n", s, S,
command);
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
ASSERT(discovery != NULL, return;);
skb = dev_alloc_skb(64);
if (!skb)
return;
skb_put(skb, 14);
frame = (struct xid_frame *) 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->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->hints.byte[0] & HINT_EXTENSION) {
info = skb_put(skb, 2);
info[0] = discovery->hints.byte[0];
info[1] = discovery->hints.byte[1];
} else {
info = skb_put(skb, 1);
info[0] = discovery->hints.byte[0];
}
info = skb_put(skb, 1);
info[0] = discovery->charset;
len = IRDA_MIN(discovery->name_len, skb_tailroom(skb));
info = skb_put(skb, len);
memcpy(info, discovery->nickname, len);
}
irlap_queue_xmit(self, 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, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, 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, __FUNCTION__
"(), frame is not addressed to us!\n");
return;
}
if ((discovery = kmalloc(sizeof(discovery_t), GFP_ATOMIC)) == NULL) {
WARNING(__FUNCTION__ "(), kmalloc failed!\n");
return;
}
memset(discovery, 0, sizeof(discovery_t));
discovery->daddr = info->daddr;
discovery->saddr = self->saddr;
discovery->timestamp = jiffies;
IRDA_DEBUG(4, __FUNCTION__ "(), daddr=%08x\n", discovery->daddr);
discovery_info = skb_pull(skb, sizeof(struct xid_frame));
/* Get info returned from peer */
discovery->hints.byte[0] = discovery_info[0];
if (discovery_info[0] & HINT_EXTENSION) {
IRDA_DEBUG(4, "EXTENSION\n");
discovery->hints.byte[1] = discovery_info[1];
discovery->charset = discovery_info[2];
text = (char *) &discovery_info[3];
} else {
discovery->hints.byte[1] = 0;
discovery->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->nickname, text, NICKNAME_MAX_LEN);
discovery->name_len = strlen(discovery->nickname);
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;
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, __FUNCTION__
"(), frame is not addressed to us!\n");
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!! */
dev_kfree_skb(skb);
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) || (skb->len < 3)) {
ERROR(__FUNCTION__ "(), discovery frame to short!\n");
return;
}
/*
* We now have some discovery info to deliver!
*/
discovery = kmalloc(sizeof(discovery_t), GFP_ATOMIC);
if (!discovery) {
WARNING(__FUNCTION__ "(), unable to malloc!\n");
return;
}
discovery->daddr = info->daddr;
discovery->saddr = self->saddr;
discovery->timestamp = jiffies;
discovery->hints.byte[0] = discovery_info[0];
if (discovery_info[0] & HINT_EXTENSION) {
discovery->hints.byte[1] = discovery_info[1];
discovery->charset = discovery_info[2];
text = (char *) &discovery_info[3];
} else {
discovery->hints.byte[1] = 0;
discovery->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->nickname, text, NICKNAME_MAX_LEN);
discovery->name_len = strlen(discovery->nickname);
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 *skb;
__u8 *frame;
skb = dev_alloc_skb(16);
if (!skb)
return;
frame = skb_put(skb, 2);
frame[0] = self->caddr;
frame[0] |= (command) ? CMD_FRAME : 0;
frame[1] = RR | PF_BIT | (self->vr << 5);
irlap_queue_xmit(self, 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 *skb;
__u8 *frame;
skb = dev_alloc_skb(16);
if (!skb)
return;
frame = skb_put(skb, 2);
frame[0] = self->caddr;
frame[1] = RD_RSP | PF_BIT;
irlap_queue_xmit(self, 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);
}
void irlap_send_frmr_frame( struct irlap_cb *self, int command)
{
struct sk_buff *skb = NULL;
__u8 *frame;
ASSERT( self != NULL, return;);
ASSERT( self->magic == LAP_MAGIC, return;);
skb = dev_alloc_skb( 32);
if (!skb)
return;
frame = skb_put( skb, 2);
frame[0] = self->caddr;
frame[0] |= (command) ? CMD_FRAME : 0;
frame[1] = (self->vs << 1);
frame[1] |= PF_BIT;
frame[1] |= (self->vr << 5);
frame[2] = 0;
IRDA_DEBUG(4, __FUNCTION__ "(), vr=%d, %ld\n",self->vr, jiffies);
irlap_queue_xmit(self, skb);
}
/*
* 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, __FUNCTION__ "(), nr=%d, %ld\n", 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, __FUNCTION__ "()\n");
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, __FUNCTION__ "()\n");
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, __FUNCTION__ "()\n");
/* 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);
/* Copy buffer */
tx_skb = skb_clone(skb, GFP_ATOMIC);
if (tx_skb == NULL) {
return;
}
/*
* Insert frame in store, in case of retransmissions
*/
skb_queue_tail(&self->wx_list, skb_get(skb));
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, __FUNCTION__ "(), sending unreliable frame\n");
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;
/* 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);
/* Copy buffer */
tx_skb = skb_clone(skb, GFP_ATOMIC);
if (tx_skb == NULL) {
return;
}
/*
* Insert frame in store, in case of retransmissions
*/
skb_queue_tail(&self->wx_list, skb_get(skb));
/*
* 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.
*/
/* Stop P timer */
del_timer(&self->poll_timer);
tx_skb->data[1] |= PF_BIT;
self->vs = (self->vs + 1) % 8;
self->ack_required = FALSE;
self->window = self->window_size;
irlap_start_final_timer(self, self->final_timeout);
irlap_send_i_frame(self, tx_skb, CMD_FRAME);
} else {
IRDA_DEBUG(4, __FUNCTION__ "(), sending unreliable frame\n");
del_timer(&self->poll_timer);
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);
}
self->window = self->window_size;
irlap_start_final_timer(self, self->final_timeout);
}
}
/*
* 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;
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
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);
tx_skb = skb_clone(skb, GFP_ATOMIC);
if (tx_skb == NULL) {
return;
}
/* Insert frame in store */
skb_queue_tail(&self->wx_list, skb_get(skb));
tx_skb->data[1] |= PF_BIT;
self->vs = (self->vs + 1) % 8;
self->window = self->window_size;
self->ack_required = FALSE;
irlap_start_wd_timer(self, self->wd_timeout);
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;
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);
tx_skb = skb_clone(skb, GFP_ATOMIC);
if (tx_skb == NULL) {
return;
}
/* Insert frame in store */
skb_queue_tail(&self->wx_list, skb_get(skb));
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;
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
/* Initialize variables */
skb = tx_skb = NULL;
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, __FUNCTION__ "(), unable to copy\n");
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 additinal data frames
*/
while (skb_queue_len( &self->txq) > 0) {
IRDA_DEBUG(0, __FUNCTION__ "(), sending additional frames!\n");
if ((skb_queue_len( &self->txq) > 0) &&
(self->window > 0)) {
skb = skb_dequeue( &self->txq);
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;
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
/* Initialize variables */
skb = tx_skb = NULL;
/* 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, __FUNCTION__ "(), unable to copy\n");
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, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
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
*/
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, __FUNCTION__ "()\n");
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, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == LAP_MAGIC, return;);
ASSERT(skb != NULL, return;);
ASSERT(info != NULL, 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 *skb;
struct test_frame *frame;
__u8 *info;
skb = dev_alloc_skb(cmd->len+sizeof(struct test_frame));
if (!skb)
return;
/* Broadcast frames must include saddr and daddr fields */
if (caddr == CBROADCAST) {
frame = (struct test_frame *)
skb_put(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(skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);
frame->caddr = caddr;
frame->control = TEST_RSP | PF_BIT;
/* Copy info */
info = skb_put(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, 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, __FUNCTION__ "()\n");
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, __FUNCTION__
"() test frame to short!\n");
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.
*
*/
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;
}
/* Check if frame is large enough for parsing */
if (skb->len < 2) {
ERROR(__FUNCTION__ "(), frame to short!\n");
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, __FUNCTION__ "(), wrong connection address!\n");
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:
WARNING(__FUNCTION__
"() Unknown S-frame %02x received!\n",
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:
WARNING(__FUNCTION__ "(), Unknown frame %02x received!\n",
info.control);
break;
}
out:
dev_kfree_skb(skb);
return 0;
}
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