diff options
Diffstat (limited to 'net/802/llc.c')
| -rw-r--r-- | net/802/llc.c | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/net/802/llc.c b/net/802/llc.c new file mode 100644 index 000000000..d280fb38f --- /dev/null +++ b/net/802/llc.c @@ -0,0 +1,412 @@ +/* + * 802.2 Class 2 LLC service. + */ + + +int llc_rx_adm(struct sock *sk,struct sk_buff *skb, int type, int cmd, int pf, int nr, int ns) +{ + if(type==CMD) + { + if(cmd==DISC) + send_response(sk,DM|pf); + else if(cmd==SABM) + { + if(sk->state!=TCP_LISTEN) + send_response(sk. DM|pf); + else + { + sk=ll_rx_accept(sk); + if(sk!=NULL) + { + send_response(sk, UA|pf); + sk->llc.vs=0; + sk->llc.vr=0; + sk->llc.p_flag=0; + sk->llc.remote_busy=0; + llc_state(sk,LLC_NORMAL); + } + } + } + else if(pf) + send_response(sk, DM|PF); + } + return 0; +} + +int llc_rx_setup(struct sock *sk, struct sk_buff *skb, int type, int cmd, int pf, int nr, int ns) +{ + if(type==CMD) + { + if(cmd==SABM) + { + sk->llc.vs=0; + sk->llc.vr=0; + send_response(sk, UA|pf); + } + if(cmd==DISC) + { + send_response(sk, DM|pf); + llc_error(sk,ECONNRESET); + llc_state(sk, LLC_ADM); + } + } + else + { + if(cmd==UA && pf==sk->llc.p_flag) + { + del_timer(&sk->llc.t1); + sk->llc.vs=0; + llc_update_p_flag(sk,pf); + llc_state(sk,LLC_NORMAL); + } + if(cmd==DM) + { + llc_error(sk, ECONNRESET); + llc_state(sk, LLC_ADM); + } + } +} + +int llc_rx_reset(struct sock *sk, struct sk_buff *skb, int type, int cmd, int pf, int nr, int ns) +{ + if(type==CMD) + { + if(cmd==SABM) + { + sk->llc.vr=0; + sk->llc.vs=0; + send_response(sk, UA|pf); + } + else if(cmd==DISC) + { + if(sk->llc.cause_flag==1) + llc_shutdown(sk,SHUTDOWN_MASK); + else + llc_eror(sk, ECONNREFUSED); + send_response(sk, DM|pf); + llc_state(sk, LLC_ADM); + } + } + else + { + if(cmd==UA) + { + if(sk->llc.p_flag==pf) + { + del_timer(&sk->llc.t1); + sk->llc.vs=0; + sk->llc.vr=0; + llc_update_p_flag(sk,pf); + llc_confirm_reset(sk, sk->llc.cause_flag); + sk->llc.remote_busy=0; + llc_state(sk, LLC_NORMAL); + } + } + if(cmd==DM) + { /* Should check cause_flag */ + llc_shutdown(sk, SHUTDOWN_MASK); + llc_state(sk, LLC_ADM); + } + } + return 0; +} + +int llc_rx_d_conn(struct sock *sk, struct sk_buff *skb, int type, int cmd, int pf, int nr, int ns) +{ + if(type==CMD) + { + if(cmd==SABM) + { + llc_error(sk, ECONNRESET); + llc_state(sk, ADM); + } + else if(cmd==DISC) + { + send_response(UA|pf); + llc_state(sk, LLC_D_CONN); + } + else if(pf) + send_response(sk, DM|PF); + } + else + { + if(cmd==UA && pf==sk->llc.p_flag) + { + del_timer(&sk->llc.t1); + llc_state(sk, ADM); + llc_confirm_reset(sk, sk->llc.cause_flag); + } + if(cmd==DM) + { + del_timer(&sk->llc.t1); + /*if(sk->llc.cause_flag)*/ + llc_shutdown(sk, SHUTDOWN_MASK); + } + + } + return 0; +} + +int llc_rx_error(struct sock *sk, struct sk_buff *skb, int type, int cmd, int pf, int nr, int ns) +{ + if(type==CMD) + { + if(cmd==SABM) + { + sk->llc.vs=0; + sk->llc.vr=0; + send_response(sk, UA|pf); + llc_error(sk,ECONNRESET); + sk->llc.p_flag=0; + sk->llc.remote_busy=0; + llc_state(sk, LLC_NORMAL); + } + else if(cmd==DISC) + { + send_response(sk, UA|pf); + llc_shutdown(sk, SHUTDOWN_MASK); + llc_state(sk, LLC_ADM); + } + else + llc_resend_frmr_rsp(sk,pf); + } + else + { + if(cmd==DM) + { + llc_error(sk, ECONNRESET); + del_timer(&sk->llc.t1); + llc_state(sk, LLC_ADM); + } + if(cmd==FRMR) + { + send_command(sk, SABM); + sk->llc.p_flag=pf; + llc_start_t1(); + sk->llc.retry_count=0; + sk->llc.cause_flag=0; + llc_error(sk, EPROTO); + llc_state(sk, LLC_RESET); + } + } +} + + +/* + * Subroutine for handling the shared cases of the data modes. + */ + +int llc_rx_nr_shared(struct sock *sk, struct sk_buff *skb, int type, int cmd, int pf, int nr, int ns) +{ + if(type==CMD) + { + if(cmd==SABM) + { + /* + * Optional reset processing. We decline resets. + */ + send_response(sk,DM|pf); + llc_error(sk, ECONNRESET); + llc_state(sk, LLC_ADM); + } + else if(cmd==DISC) + { + send_response(sk,UA|pf); + llc_state(sk, LLC_ADM); + llc_shutdown(sk, SHUTDOWN_MASK); + } + /* + * We only ever use windows of 7, so there is no illegal NR/NS value + * otherwise we would FRMR here and go to ERROR state + */ + else if(cmd==ILLEGAL) + { + llc_send_frmr_response(sk, ILLEGAL_TYPE,pf); + llc_state(sk, LLC_ERROR); + llc_error(sk, EPROTO); + } + else + /* + * Not covered by general rule + */ + return 0; + } + else + { + /* + * We close on errors + */ + if(cmd==FRMR) + { + send_command(sk, DM|pf); + sk->llc.p_flag=pf; + llc_start_t1(sk); + llc_error(sk, EPROTO); + sk->llc.cause_flag=0; + llc_state(sk, LLC_D_CONN): + } + else if(cmd==DM) + { + llc_state(sk, LLC_ADM); + llc_error(sk, ECONNREFUSED); + } + /* + * We always use a window of 7 so can't get I resp + * with invalid NS, or any resp with invalid NR. If + * we add this they do the same as.. + */ + else if(cmd==UA) + { + llc_send_frmr_response(sk, UNEXPECTED_CONTROL, pf); + llc_state(sk, LLC_ERROR); + llc_error(sk, EPROTO); + } + else if(pf==1 && sk->llc.p_flag==0) + { + llc_send_frmr_response(sk, UNEXPECTED_RESPONSE, pf); + llc_state(sk, LLC_ERROR); + llc_error(sk, EPROTO); + } + else if(cmd==ILLEGAL) + { + llc_send_frmr_response(sk, ILLEGAL_TYPE,pf); + llc_state(sk, LLC_ERROR); + llc_error(sk, EPROTO); + } + else + /* + * Not covered by general rule + */ + return 0 + } + /* + * Processed. + */ + return 1; +} + +int llc_rx_normal(struct sock *sk, struct sk_buff *skb, int type, int cmd, int pf, int nr, int ns) +{ + if(llc_rx_nr_shared(sk, skb, type, cmd, pf, nr, ns)) + return 0; + if(cmd==I) + { + if(llc_invalid_ns(sk,ns)) + { + if((type==RESP && sk->llc.p_flag==pf)||(type==CMD && pf==0 && sk->llc.p_flag==0)) + { + llc_command(sk, REJ|PF); + llc_ack_frames(sk,nr); /* Ack frames and update N(R) */ + sk->llc.p_flag=PF; + llc_state(sk, LLC_REJECT); + sk->llc.retry_count=0; + llc_start_t1(sk); + sk->llc.remote_busy=0; + } + else if((type==CMD && !pf && sk->llc.p_flag==1) || (type==RESP && !pf && sk->llc.p_flag==1)) + { + if(type==CMD) + llc_response(sk, REJ); + else + llc_command(sk, REJ); + llc_ack_frames(sk,nr); + sk->llc.retry_count=0; + llc_state(sk, LLC_REJECT); + llc_start_t1(sk); + } + else if(pf && type==CMD) + { + llc_response(sk, REJ|PF); + llc_ack_frames(sk,nr); + sk->llc.retry_count=0; + llc_start_t1(sk); + } + } + else + { + /* + * Valid I frame cases + */ + + if(sk->llc.p_flag==pf && !(type==CMD && pf)) + { + sk->llc.vr=(sk->llc.vr+1)&7; + llc_queue_rr_cmd(sk, PF); + sk->llc.retry_count=0; + llc_start_t1(sk); + sk->llc.p_flag=1; + llc_ack_frames(sk,nr); + sk->llc.remote_busy=0; + } + else if(sk->ppc.p_flag!=pf) + { + sk->llc.vr=(sk->llc.vr+1)&7; + if(type==CMD) + llc_queue_rr_resp(sk, 0); + else + llc_queue_rr_cmd(sk, 0); + if(sk->llc.nr!=nr) + { + llc_ack_frames(sk,nr); + llc_reset_t1(sk); + } + } + else if(pf) + { + sk->llc.vr=(sk->llc.vr+1)&7; + llc_queue_rr_resp(sk,PF); + if(sk->llc.nr!=nr) + { + llc_ack_frames(sk,nr); + llc_reset_t1(sk); + } + } + llc_queue_data(sk,skb); + return 1; + } + } + else if(cmd==RR||cmd==RNR) + { + if(type==CMD || (type==RESP && (!pf || pf==1 && sk->llc.p_flag==1))) + { + llc_update_p_flag(sk,pf); + if(sk->llc.nr!=nr) + { + llc_ack_frames(sk,nr); + llc_reset_t1(sk); + } + if(cmd==RR) + sk->llc.remote_busy=0; + else + { sk->llc.remote_busy=1; + if(!llc_t1_running(sk)) + llc_start_t1(sk); + } + } + else if(type==cmd && pf) + { + if(cmd==RR) + llc_queue_rr_resp(sk,PF); + else + { + send_response(sk, RR|PF); + if(!llc_t1_running(sk)) + llc_start_t1(sk); + } + if(sk->llc.nr!=nr) + { + llc_ack_frames(sk,nr); + llc_reset_t1(sk); + } + if(cmd==RR) + sk->llc.remote_busy=0; + else + sk->llc.remote_busy=1; + } + } + else if(cmd==REJ) + { + + } +} + |