/********************************************************************* * * Filename: irlap_frame.c * Version: 0.9 * Description: Build and transmit IrLAP frames * Status: Experimental. * Author: Dag Brattli * Created at: Tue Aug 19 10:27:26 1997 * Modified at: Sat Oct 9 09:42:11 1999 * Modified by: Dag Brattli * * Copyright (c) 1998-1999 Dag Brattli , * All Rights Resrved. * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * 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. * */ 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->speed = self->qos_tx.baud_rate.value; /* 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+self->xbofs_delay; /* Reset XBOF's delay (used only for getting min turn time) */ self->xbofs_delay = 0; } /* * 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) { /* Make sure data is not larger than max data size plus LAP header */ if (skb->len > 2050) { ERROR(__FUNCTION__ "(), size=%d of sk_buff to big!\n", (int) skb->len); return; } /* 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; skb_put(skb, 2); frame = (struct snrm_frame *) skb->data; /* 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"); dev_kfree_skb(skb); 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"); dev_kfree_skb(skb); 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; skb_put(skb, 10); frame = (struct ua_frame *) skb->data; /* 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; skb_put( skb, 2); frame = skb->data; 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(32); if (!skb) return; skb_put(skb, 2); frame = skb->data; 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 i; if (discovery->hints.byte[0] & HINT_EXTENSION) info = skb_put(skb, 3+discovery->name_len); else info = skb_put(skb, 2+discovery->name_len); i = 0; info[i++] = discovery->hints.byte[0]; if (discovery->hints.byte[0] & HINT_EXTENSION) info[i++] = discovery->hints.byte[1]; info[i++] = discovery->charset; memcpy(&info[i++], discovery->nickname, discovery->name_len); } ASSERT(self->netdev != NULL, return;); 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)) { dev_kfree_skb(skb); 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 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"); dev_kfree_skb(skb); 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) { /* * 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(32); 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_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; skb_put( skb, 2); frame = skb->data; 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) { __u8 *frame; ASSERT( skb != NULL, return;); ASSERT( info != NULL, return;); frame = skb->data; info->nr = frame[1] >> 5; IRDA_DEBUG( 4, __FUNCTION__ "(), nr=%d, %ld\n", info->nr, jiffies); irlap_do_event( self, RECV_RNR_FRAME, skb, info); } /* * Function irlap_recv_ua_frame (skb, frame) * * Received UA (Unnumbered Acknowledgement) frame * */ static 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) { dev_kfree_skb(skb); return; } /* * make sure the skb->sk accounting of memory usage is sane */ if (skb->sk != NULL) skb_set_owner_w(tx_skb, skb->sk); /* * Insert frame in store, in case of retransmissions */ skb_queue_tail(&self->wx_list, 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, 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) { dev_kfree_skb(skb); return; } /* * make sure the skb->sk accounting of memory usage is sane */ if (skb->sk != NULL) skb_set_owner_w(tx_skb, skb->sk); /* * Insert frame in store, in case of retransmissions */ skb_queue_tail(&self->wx_list, 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, 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, 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) { dev_kfree_skb(skb); return; } if (skb->sk != NULL) skb_set_owner_w(tx_skb, skb->sk); /* Insert frame in store */ skb_queue_tail(&self->wx_list, 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, 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, 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) { dev_kfree_skb(skb); return; } if (skb->sk != NULL) skb_set_owner_w(tx_skb, skb->sk); /* Insert frame in store */ skb_queue_tail(&self->wx_list, 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, RSP_FRAME); self->window -= 1; } } /* * Function irlap_resend_rejected_frames (nr) * * Resend frames which has not been acknowledged. TODO: check that the * traversal of the list is atomic, i.e that no-one tries to insert or * remove frames from the list while we travers it! * * FIXME: It is not safe to traverse a this list without locking it! */ 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; /* * Resend all unacknowledged frames */ count = skb_queue_len(&self->wx_list); 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 == NULL) { /* Unlink tx_skb from list */ tx_skb->next = tx_skb->prev = NULL; tx_skb->list = NULL; dev_kfree_skb(skb); return; } /* Unlink tx_skb from list */ tx_skb->next = tx_skb->prev = NULL; tx_skb->list = NULL; /* * make sure the skb->sk accounting of memory usage is sane */ if (skb->sk != NULL) skb_set_owner_w(tx_skb, skb->sk); /* 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; } /* * We can now fill the window with additinal data frames */ return; /* Skip this for now, DB */ while (skb_queue_len( &self->tx_list) > 0) { IRDA_DEBUG(0, __FUNCTION__ "(), sending additional frames!\n"); if ((skb_queue_len( &self->tx_list) > 0) && (self->window > 0)) { skb = skb_dequeue( &self->tx_list); ASSERT(skb != NULL, return;); /* * If send window > 1 then send frame with pf * bit cleared */ if ((self->window > 1) && skb_queue_len(&self->tx_list) > 0) { irlap_send_data_primary(self, skb); } else { irlap_send_data_primary_poll(self, skb); } } } } /* * 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, int command) { __u8 *frame; IRDA_DEBUG(4, __FUNCTION__ "()\n"); ASSERT(self != NULL, return;); ASSERT(self->magic == LAP_MAGIC, return;); ASSERT(skb != NULL, return;); frame = skb->data; /* Insert connection address */ frame[0] = self->caddr; frame[0] |= (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) { __u8 *frame; IRDA_DEBUG( 4, __FUNCTION__ "()\n"); frame = skb->data; info->pf = frame[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, __u32 daddr, struct sk_buff *cmd) { struct sk_buff *skb; struct test_frame *frame; __u8 *info; skb = dev_alloc_skb(32); if (!skb) return; skb_put(skb, sizeof(struct test_frame)); frame = (struct test_frame *) skb->data; /* Build header */ if (self->state == LAP_NDM) frame->caddr = CBROADCAST; /* Send response */ else frame->caddr = self->caddr; frame->control = TEST_RSP; /* Insert the swapped addresses */ frame->saddr = cpu_to_le32(self->saddr); frame->daddr = cpu_to_le32(daddr); /* 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 * */ 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"); if (skb->len < sizeof(struct test_frame)) { IRDA_DEBUG(0, __FUNCTION__ "() test frame to short!\n"); return; } frame = (struct test_frame *) skb->data; /* 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)) { dev_kfree_skb(skb); 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"); dev_kfree_skb(skb); return 0; } /* * 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); return 0; } /* * 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); break; case REJ: IRDA_DEBUG( 0, "*** REJ frame received! ***\n"); break; case SREJ: IRDA_DEBUG( 0, "*** SREJ frame received! ***\n"); break; default: WARNING(__FUNCTION__ "() Unknown S-frame %02x received!\n", info.control); break; } return 0; } /* * 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: IRDA_DEBUG( 0, "DM rsp frame received!\n"); irlap_next_state(self, LAP_NDM); break; case DISC_CMD: irlap_do_event(self, RECV_DISC_FRAME, skb, &info); 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); dev_kfree_skb( skb); break; } return 0; }