/********************************************************************* * * 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 Tromsø 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_reset_mac_header(skb); skb_reset_network_header(skb); skb_reset_transport_header(skb); skb->protocol = htons(ETH_P_IRDA); skb->priority = TC_PRIO_BESTEFFORT; irlap_insert_info(self, skb); if (unlikely(self->mode & IRDA_MODE_MONITOR)) { IRDA_DEBUG(3, "%s(): %s is in monitor mode\n", __func__, self->netdev->name); dev_kfree_skb(skb); return; } 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 = alloc_skb(sizeof(struct snrm_frame) + IRLAP_NEGOCIATION_PARAMS_LEN, GFP_ATOMIC); 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 parameters */ if (qos) { skb_put(tx_skb, 9); /* 25 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", __func__); 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", __func__); 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", __func__, jiffies); IRDA_ASSERT(self != NULL, return;); IRDA_ASSERT(self->magic == LAP_MAGIC, return;); /* Allocate frame */ tx_skb = alloc_skb(sizeof(struct ua_frame) + IRLAP_NEGOCIATION_PARAMS_LEN, GFP_ATOMIC); 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; struct dm_frame *frame; IRDA_ASSERT(self != NULL, return;); IRDA_ASSERT(self->magic == LAP_MAGIC, return;); tx_skb = alloc_skb(sizeof(struct dm_frame), GFP_ATOMIC); if (!tx_skb) return; frame = (struct dm_frame *)skb_put(tx_skb, 2); if (self->state == LAP_NDM) frame->caddr = CBROADCAST; else frame->caddr = self->caddr; frame->control = 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; struct disc_frame *frame; IRDA_DEBUG(3, "%s()\n", __func__); IRDA_ASSERT(self != NULL, return;); IRDA_ASSERT(self->magic == LAP_MAGIC, return;); tx_skb = alloc_skb(sizeof(struct disc_frame), GFP_ATOMIC); if (!tx_skb) return; frame = (struct disc_frame *)skb_put(tx_skb, 2); frame->caddr = self->caddr | CMD_FRAME; frame->control = 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", __func__, s, S, command); IRDA_ASSERT(self != NULL, return;); IRDA_ASSERT(self->magic == LAP_MAGIC, return;); IRDA_ASSERT(discovery != NULL, return;); tx_skb = alloc_skb(sizeof(struct xid_frame) + IRLAP_DISCOVERY_INFO_LEN, GFP_ATOMIC); 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", __func__); 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 too short!\n", __func__); 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", __func__); return; } if ((discovery = kzalloc(sizeof(discovery_t), GFP_ATOMIC)) == NULL) { IRDA_WARNING("%s: kmalloc failed!\n", __func__); return; } discovery->data.daddr = info->daddr; discovery->data.saddr = self->saddr; discovery->timestamp = jiffies; IRDA_DEBUG(4, "%s(), daddr=%08x\n", __func__, 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 too short!\n", __func__); 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", __func__); 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 too short!\n", __func__); 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", __func__); 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; struct rr_frame *frame; tx_skb = alloc_skb(sizeof(struct rr_frame), GFP_ATOMIC); if (!tx_skb) return; frame = (struct rr_frame *)skb_put(tx_skb, 2); frame->caddr = self->caddr; frame->caddr |= (command) ? CMD_FRAME : 0; frame->control = 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; struct rd_frame *frame; tx_skb = alloc_skb(sizeof(struct rd_frame), GFP_ATOMIC); if (!tx_skb) return; frame = (struct rd_frame *)skb_put(tx_skb, 2); frame->caddr = self->caddr; frame->caddr = 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", __func__, 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", __func__); 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", __func__); 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", __func__); /* 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", __func__); 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_next_state(self, LAP_NRM_P); irlap_send_i_frame(self, tx_skb, CMD_FRAME); } else { IRDA_DEBUG(4, "%s(), sending unreliable frame\n", __func__); if (self->ack_required) { irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME); irlap_next_state(self, LAP_NRM_P); irlap_send_rr_frame(self, CMD_FRAME); self->ack_required = FALSE; } else { skb->data[1] |= PF_BIT; irlap_next_state(self, LAP_NRM_P); 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", __func__, 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", __func__); return; } /* 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_empty(&self->txq)) { IRDA_DEBUG(0, "%s(), sending additional frames!\n", __func__); if (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_empty(&self->txq)) { 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", __func__); return; } /* 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", __func__); 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", __func__); 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", __func__); 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 too short!\n", __func__); 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 = alloc_skb(cmd->len + sizeof(struct test_frame), GFP_ATOMIC); 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", __func__); if (!pskb_may_pull(skb, sizeof(*frame))) { IRDA_ERROR("%s: frame too short!\n", __func__); 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 too short!\n", __func__); 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 net_device *orig_dev) { struct irlap_info info; struct irlap_cb *self; int command; __u8 control; int ret = -1; if (!net_eq(dev_net(dev), &init_net)) goto out; /* 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) goto err; /* 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", __func__); goto err; } /* Check if frame is large enough for parsing */ if (!pskb_may_pull(skb, 2)) { IRDA_ERROR("%s: frame too short!\n", __func__); goto err; } 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", __func__); 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", __func__, 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", __func__, info.control); break; } out: ret = 0; err: /* Always drop our reference on the skb */ dev_kfree_skb(skb); return ret; }