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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [net/] [802/] [cl2llc.pre] - Rev 1765
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/** NET An implementation of the IEEE 802.2 LLC protocol for the* LINUX operating system. LLC is implemented as a set of* state machines and callbacks for higher networking layers.** Class 2 llc algorithm.* Pseudocode interpreter, transition table lookup,* data_request & indicate primitives...** Code for initialization, termination, registration and* MAC layer glue.** Copyright Tim Alpaerts,* <Tim_Alpaerts@toyota-motor-europe.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.** Changes* Alan Cox : Chainsawed into Linux format* Modified to use llc_ names* Changed callbacks** This file must be processed by sed before it can be compiled.*/#include <linux/types.h>#include <linux/kernel.h>#include <linux/slab.h>#include <linux/netdevice.h>#include <linux/skbuff.h>#include <net/p8022.h>#include <linux/proc_fs.h>#include <linux/stat.h>#include <asm/byteorder.h>#include "pseudo/pseudocode.h"#include "transit/pdutr.h"#include "transit/timertr.h"#include <net/llc_frame.h>#include <net/llc.h>/** Data_request() is called by the client to present a data unit* to the llc for transmission.* In the future this function should also check if the transmit window* allows the sending of another pdu, and if not put the skb on the atq* for deferred sending.*/int llc_data_request(llcptr lp, struct sk_buff *skb){if (skb_headroom(skb) < (lp->dev->hard_header_len +4)){printk("cl2llc: data_request() not enough headroom in skb\n");return -1;};skb_push(skb, 4);if ((lp->state != NORMAL) && (lp->state != BUSY) && (lp->state != REJECT)){printk("cl2llc: data_request() while no llc connection\n");return -1;}if (lp->remote_busy){ /* if the remote llc is BUSY, */ADD_TO_ATQ(skb); /* save skb in the await transmit queue */return 0;}else{/** Else proceed with xmit*/switch(lp->state){case NORMAL:if(lp->p_flag)llc_interpret_pseudo_code(lp, NORMAL2, skb, NO_FRAME);elsellc_interpret_pseudo_code(lp, NORMAL1, skb, NO_FRAME);break;case BUSY:if (lp->p_flag)llc_interpret_pseudo_code(lp, BUSY2, skb, NO_FRAME);elsellc_interpret_pseudo_code(lp, BUSY1, skb, NO_FRAME);break;case REJECT:if (lp->p_flag)llc_interpret_pseudo_code(lp, REJECT2, skb, NO_FRAME);elsellc_interpret_pseudo_code(lp, REJECT1, skb, NO_FRAME);break;default:;}if(lp->llc_callbacks){lp->llc_event(lp);lp->llc_callbacks=0;}return 0;}}/** Disconnect_request() requests that the llc to terminate a connection*/void disconnect_request(llcptr lp){if ((lp->state == NORMAL) ||(lp->state == BUSY) ||(lp->state == REJECT) ||(lp->state == AWAIT) ||(lp->state == AWAIT_BUSY) ||(lp->state == AWAIT_REJECT)){lp->state = D_CONN;llc_interpret_pseudo_code(lp, SH1, NULL, NO_FRAME);if(lp->llc_callbacks){lp->llc_event(lp);lp->llc_callbacks=0;}/** lp may be invalid after the callback*/}}/** Connect_request() requests that the llc to start a connection*/void connect_request(llcptr lp){if (lp->state == ADM){lp->state = SETUP;llc_interpret_pseudo_code(lp, ADM1, NULL, NO_FRAME);if(lp->llc_callbacks){lp->llc_event(lp);lp->llc_callbacks=0;}/** lp may be invalid after the callback*/}}/** Interpret_pseudo_code() executes the actions in the connection component* state transition table. Table 4 in document on p88.** If this function is called to handle an incoming pdu, skb will point* to the buffer with the pdu and type will contain the decoded pdu type.** If called by data_request skb points to an skb that was skb_alloc-ed by* the llc client to hold the information unit to be transmitted, there is* no valid type in this case.** If called because a timer expired no skb is passed, and there is no* type.*/void llc_interpret_pseudo_code(llcptr lp, int pc_label, struct sk_buff *skb,char type){short int pc; /* program counter in pseudo code array */char p_flag_received;frameptr fr;int resend_count; /* number of pdus resend by llc_resend_ipdu() */int ack_count; /* number of pdus acknowledged */struct sk_buff *skb2;if (skb != NULL){fr = (frameptr) skb->data;}elsefr = NULL;pc = pseudo_code_idx[pc_label];while(pseudo_code[pc]){switch(pseudo_code[pc]){case IF_F=1_CLEAR_REMOTE_BUSY:if ((type != I_CMD) || (fr->i_hdr.i_pflag == 0))break;case CLEAR_REMOTE_BUSY:lp->remote_busy = 0;llc_stop_timer(lp, BUSY_TIMER);if ((lp->state == NORMAL) ||(lp->state == REJECT) ||(lp->state == BUSY)){skb2 = llc_pull_from_atq(lp);if (skb2 != NULL)llc_start_timer(lp, ACK_TIMER);while (skb2 != NULL){llc_sendipdu( lp, I_CMD, 0, skb2);skb2 = llc_pull_from_atq(lp);}}break;case CONNECT_INDICATION:lp->state = NORMAL; /* needed to eliminate connect_response() */lp->llc_mode = MODE_ABM;lp->llc_callbacks|=LLC_CONN_INDICATION;break;case CONNECT_CONFIRM:lp->llc_mode = MODE_ABM;lp->llc_callbacks|=LLC_CONN_CONFIRM;break;case DATA_INDICATION:skb_pull(skb, 4);lp->inc_skb=skb;lp->llc_callbacks|=LLC_DATA_INDIC;break;case DISCONNECT_INDICATION:lp->llc_mode = MODE_ADM;lp->llc_callbacks|=LLC_DISC_INDICATION;break;case RESET_INDICATION(LOCAL):lp->llc_callbacks|=LLC_RESET_INDIC_LOC;break;case RESET_INDICATION(REMOTE):lp->llc_callbacks|=LLC_RESET_INDIC_REM;break;case RESET_CONFIRM:lp->llc_callbacks|=LLC_RST_CONFIRM;break;case REPORT_STATUS(FRMR_RECEIVED):lp->llc_callbacks|=LLC_FRMR_RECV;break;case REPORT_STATUS(FRMR_SENT):lp->llc_callbacks|=LLC_FRMR_SENT;break;case REPORT_STATUS(REMOTE_BUSY):lp->llc_callbacks|=LLC_REMOTE_BUSY;break;case REPORT_STATUS(REMOTE_NOT_BUSY):lp->llc_callbacks|=LLC_REMOTE_NOTBUSY;break;case SEND_DISC_CMD(P=X):llc_sendpdu(lp, DISC_CMD, lp->f_flag, 0, NULL);break;case SEND_DM_RSP(F=X):llc_sendpdu(lp, DM_RSP, 0, 0, NULL);break;case SEND_FRMR_RSP(F=X):lp->frmr_info_fld.cntl1 = fr->pdu_cntl.byte1;lp->frmr_info_fld.cntl2 = fr->pdu_cntl.byte2;lp->frmr_info_fld.vs = lp->vs;lp->frmr_info_fld.vr_cr = lp->vr;llc_sendpdu(lp, FRMR_RSP, 0, 5, (char *) &lp->frmr_info_fld);break;case RE-SEND_FRMR_RSP(F=0):llc_sendpdu(lp, FRMR_RSP, 0, 5, (char *) &lp->frmr_info_fld);break;case RE-SEND_FRMR_RSP(F=P):llc_sendpdu(lp, FRMR_RSP, lp->p_flag,5, (char *) &lp->frmr_info_fld);break;case SEND_I_CMD(P=1):llc_sendipdu(lp, I_CMD, 1, skb);break;case RE-SEND_I_CMD(P=1):resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 1);break;case RE-SEND_I_CMD(P=1)_OR_SEND_RR:resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 1);if (resend_count == 0){llc_sendpdu(lp, RR_CMD, 1, 0, NULL);}break;case SEND_I_XXX(X=0):llc_sendipdu(lp, I_CMD, 0, skb);break;case RE-SEND_I_XXX(X=0):resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 0);break;case RE-SEND_I_XXX(X=0)_OR_SEND_RR:resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 0);if (resend_count == 0){llc_sendpdu(lp, RR_CMD, 0, 0, NULL);}break;case RE-SEND_I_RSP(F=1):resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_RSP, 1);break;case SEND_REJ_CMD(P=1):llc_sendpdu(lp, REJ_CMD, 1, 0, NULL);break;case SEND_REJ_RSP(F=1):llc_sendpdu(lp, REJ_RSP, 1, 0, NULL);break;case SEND_REJ_XXX(X=0):if (IS_RSP(fr))llc_sendpdu(lp, REJ_CMD, 0, 0, NULL);elsellc_sendpdu(lp, REJ_RSP, 0, 0, NULL);break;case SEND_RNR_CMD(F=1):llc_sendpdu(lp, RNR_CMD, 1, 0, NULL);break;case SEND_RNR_RSP(F=1):llc_sendpdu(lp, RNR_RSP, 1, 0, NULL);break;case SEND_RNR_XXX(X=0):if (IS_RSP(fr))llc_sendpdu(lp, RNR_CMD, 0, 0, NULL);elsellc_sendpdu(lp, RNR_RSP, 0, 0, NULL);break;case SET_REMOTE_BUSY:if (lp->remote_busy == 0){lp->remote_busy = 1;llc_start_timer(lp, BUSY_TIMER);lp->llc_callbacks|=LLC_REMOTE_BUSY;}else if (lp->timer_state[BUSY_TIMER] == TIMER_IDLE){llc_start_timer(lp, BUSY_TIMER);}break;case OPTIONAL_SEND_RNR_XXX(X=0):if (IS_RSP(fr))llc_sendpdu(lp, RNR_CMD, 0, 0, NULL);elsellc_sendpdu(lp, RNR_RSP, 0, 0, NULL);break;case SEND_RR_CMD(P=1):llc_sendpdu(lp, RR_CMD, 1, 0, NULL);break;case SEND_ACKNOWLEDGE_CMD(P=1):llc_sendpdu(lp, RR_CMD, 1, 0, NULL);break;case SEND_RR_RSP(F=1):llc_sendpdu(lp, RR_RSP, 1, 0, NULL);break;case SEND_ACKNOWLEDGE_RSP(F=1):llc_sendpdu(lp, RR_RSP, 1, 0, NULL);break;case SEND_RR_XXX(X=0):llc_sendpdu(lp, RR_RSP, 0, 0, NULL);break;case SEND_ACKNOWLEDGE_XXX(X=0):if (IS_RSP(fr))llc_sendpdu(lp, RR_CMD, 0, 0, NULL);elsellc_sendpdu(lp, RR_RSP, 0, 0, NULL);break;case SEND_SABME_CMD(P=X):llc_sendpdu(lp, SABME_CMD, 0, 0, NULL);lp->f_flag = 0;break;case SEND_UA_RSP(F=X):llc_sendpdu(lp, UA_RSP, lp->f_flag, 0, NULL);break;case S_FLAG:=0:lp->s_flag = 0;break;case S_FLAG:=1:lp->s_flag = 1;break;case START_P_TIMER:if(lp->timer_state[P_TIMER] == TIMER_RUNNING)llc_stop_timer(lp, P_TIMER);llc_start_timer(lp, P_TIMER);if (lp->p_flag == 0){lp->retry_count = 0;lp->p_flag = 1;}break;case START_ACK_TIMER_IF_NOT_RUNNING:if (lp->timer_state[ACK_TIMER] == TIMER_IDLE)llc_start_timer(lp, ACK_TIMER);break;case START_ACK_TIMER:llc_start_timer(lp, ACK_TIMER);break;case START_REJ_TIMER:llc_start_timer(lp, REJ_TIMER);break;case STOP_ACK_TIMER:llc_stop_timer(lp, ACK_TIMER);break;case STOP_P_TIMER:llc_stop_timer(lp, ACK_TIMER);lp->p_flag = 0;break;case IF_DATA_FLAG=2_STOP_REJ_TIMER:if (lp->data_flag == 2)llc_stop_timer(lp, REJ_TIMER);break;case STOP_REJ_TIMER:llc_stop_timer(lp, REJ_TIMER);break;case STOP_ALL_TIMERS:llc_stop_timer(lp, ACK_TIMER);llc_stop_timer(lp, P_TIMER);llc_stop_timer(lp, REJ_TIMER);llc_stop_timer(lp, BUSY_TIMER);break;case STOP_OTHER_TIMERS:llc_stop_timer(lp, P_TIMER);llc_stop_timer(lp, REJ_TIMER);llc_stop_timer(lp, BUSY_TIMER);break;case UPDATE_N(R)_RECEIVED:ack_count = llc_free_acknowledged_skbs(lp,(unsigned char) fr->s_hdr.nr);if (ack_count > 0){lp->retry_count = 0;llc_stop_timer(lp, ACK_TIMER);if (skb_peek(&lp->rtq) != NULL){/** Re-transmit queue not empty*/llc_start_timer(lp, ACK_TIMER);}}break;case UPDATE_P_FLAG:if (IS_UFRAME(fr))p_flag_received = fr->u_hdr.u_pflag;elsep_flag_received = fr->i_hdr.i_pflag;if ((fr->pdu_hdr.ssap & 0x01) && (p_flag_received)){lp->p_flag = 0;llc_stop_timer(lp, P_TIMER);}break;case DATA_FLAG:=2:lp->data_flag = 2;break;case DATA_FLAG:=0:lp->data_flag = 0;break;case DATA_FLAG:=1:lp->data_flag = 1;break;case IF_DATA_FLAG_=0_THEN_DATA_FLAG:=1:if (lp->data_flag == 0)lp->data_flag = 1;break;case P_FLAG:=0:lp->p_flag = 0;break;case P_FLAG:=P:lp->p_flag = lp->f_flag;break;case REMOTE_BUSY:=0:lp->remote_busy = 0;break;case RETRY_COUNT:=0:lp->retry_count = 0;break;case RETRY_COUNT:=RETRY_COUNT+1:lp->retry_count++;break;case V(R):=0:lp->vr = 0;break;case V(R):=V(R)+1:lp->vr++;break;case V(S):=0:lp->vs = 0;break;case V(S):=N(R):lp->vs = fr->i_hdr.nr;break;case F_FLAG:=P:if (IS_UFRAME(fr))lp->f_flag = fr->u_hdr.u_pflag;elselp->f_flag = fr->i_hdr.i_pflag;break;default:;}pc++;}}/** Process_otype2_frame will handle incoming frames* for 802.2 Type 2 Procedure.*/void llc_process_otype2_frame(llcptr lp, struct sk_buff *skb, char type){int idx; /* index in transition table */int pc_label; /* action to perform, from tr tbl */int validation; /* result of validate_seq_nos */int p_flag_received; /* p_flag in received frame */frameptr fr;fr = (frameptr) skb->data;if (IS_UFRAME(fr))p_flag_received = fr->u_hdr.u_pflag;elsep_flag_received = fr->i_hdr.i_pflag;switch(lp->state){/* Compute index in transition table: */case ADM:idx = type;idx = (idx << 1) + p_flag_received;break;case CONN:case RESET_WAIT:case RESET_CHECK:case ERROR:idx = type;break;case SETUP:case RESET:case D_CONN:idx = type;idx = (idx << 1) + lp->p_flag;break;case NORMAL:case BUSY:case REJECT:case AWAIT:case AWAIT_BUSY:case AWAIT_REJECT:validation = llc_validate_seq_nos(lp, fr);if (validation > 3)type = BAD_FRAME;idx = type;idx = (idx << 1);if (validation & 1)idx = idx +1;idx = (idx << 1) + p_flag_received;idx = (idx << 1) + lp->p_flag;default:printk("llc_proc: bad state\n");return;}idx = (idx << 1) + pdutr_offset[lp->state];lp->state = pdutr_entry[idx +1];pc_label = pdutr_entry[idx];if (pc_label != NOP){llc_interpret_pseudo_code(lp, pc_label, skb, type);if(lp->llc_callbacks){lp->llc_event(lp);lp->llc_callbacks=0;}/** lp may no longer be valid after this point. Be* careful what is added!*/}}void llc_timer_expired(llcptr lp, int t){int idx; /* index in transition table */int pc_label; /* action to perform, from tr tbl */lp->timer_state[t] = TIMER_EXPIRED;idx = lp->state; /* Compute index in transition table: */idx = (idx << 2) + t;idx = idx << 1;if (lp->retry_count >= lp->n2)idx = idx + 1;idx = (idx << 1) + lp->s_flag;idx = (idx << 1) + lp->p_flag;idx = idx << 1; /* 2 bytes per entry: action & newstate */pc_label = timertr_entry[idx];if (pc_label != NOP){llc_interpret_pseudo_code(lp, pc_label, NULL, NO_FRAME);lp->state = timertr_entry[idx +1];}lp->timer_state[t] = TIMER_IDLE;if(lp->llc_callbacks){lp->llc_event(lp);lp->llc_callbacks=0;}/** And lp may have vanished in the event callback*/}