From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- net/lapb/lapb_in.c | 562 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 562 insertions(+) create mode 100644 net/lapb/lapb_in.c (limited to 'net/lapb/lapb_in.c') diff --git a/net/lapb/lapb_in.c b/net/lapb/lapb_in.c new file mode 100644 index 000000000..5dba89913 --- /dev/null +++ b/net/lapb/lapb_in.c @@ -0,0 +1,562 @@ +/* + * LAPB release 002 + * + * This code REQUIRES 2.1.15 or higher/ NET3.038 + * + * This module: + * This module 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. + * + * History + * LAPB 001 Jonathan Naulor Started Coding + * LAPB 002 Jonathan Naylor New timer architecture. + * 2000-10-29 Henner Eisen lapb_data_indication() return status. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * State machine for state 0, Disconnected State. + * The handling of the timer(s) is in file lapb_timer.c. + */ +static void lapb_state0_machine(struct lapb_cb *lapb, struct sk_buff *skb, + struct lapb_frame *frame) +{ + switch (frame->type) { + case LAPB_SABM: + lapb_dbg(1, "(%p) S0 RX SABM(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S0 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } else { + lapb_dbg(1, "(%p) S0 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_dbg(0, "(%p) S0 -> S3\n", lapb->dev); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_3; + lapb->condition = 0x00; + lapb->n2count = 0; + lapb->vs = 0; + lapb->vr = 0; + lapb->va = 0; + lapb_connect_indication(lapb, LAPB_OK); + } + break; + + case LAPB_SABME: + lapb_dbg(1, "(%p) S0 RX SABME(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S0 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_dbg(0, "(%p) S0 -> S3\n", lapb->dev); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_3; + lapb->condition = 0x00; + lapb->n2count = 0; + lapb->vs = 0; + lapb->vr = 0; + lapb->va = 0; + lapb_connect_indication(lapb, LAPB_OK); + } else { + lapb_dbg(1, "(%p) S0 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } + break; + + case LAPB_DISC: + lapb_dbg(1, "(%p) S0 RX DISC(%d)\n", lapb->dev, frame->pf); + lapb_dbg(1, "(%p) S0 TX UA(%d)\n", lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_UA, frame->pf, LAPB_RESPONSE); + break; + + default: + break; + } + + kfree_skb(skb); +} + +/* + * State machine for state 1, Awaiting Connection State. + * The handling of the timer(s) is in file lapb_timer.c. + */ +static void lapb_state1_machine(struct lapb_cb *lapb, struct sk_buff *skb, + struct lapb_frame *frame) +{ + switch (frame->type) { + case LAPB_SABM: + lapb_dbg(1, "(%p) S1 RX SABM(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S1 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } else { + lapb_dbg(1, "(%p) S1 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + } + break; + + case LAPB_SABME: + lapb_dbg(1, "(%p) S1 RX SABME(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S1 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + } else { + lapb_dbg(1, "(%p) S1 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } + break; + + case LAPB_DISC: + lapb_dbg(1, "(%p) S1 RX DISC(%d)\n", lapb->dev, frame->pf); + lapb_dbg(1, "(%p) S1 TX DM(%d)\n", lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, LAPB_RESPONSE); + break; + + case LAPB_UA: + lapb_dbg(1, "(%p) S1 RX UA(%d)\n", lapb->dev, frame->pf); + if (frame->pf) { + lapb_dbg(0, "(%p) S1 -> S3\n", lapb->dev); + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_3; + lapb->condition = 0x00; + lapb->n2count = 0; + lapb->vs = 0; + lapb->vr = 0; + lapb->va = 0; + lapb_connect_confirmation(lapb, LAPB_OK); + } + break; + + case LAPB_DM: + lapb_dbg(1, "(%p) S1 RX DM(%d)\n", lapb->dev, frame->pf); + if (frame->pf) { + lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev); + lapb_clear_queues(lapb); + lapb->state = LAPB_STATE_0; + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb_disconnect_indication(lapb, LAPB_REFUSED); + } + break; + } + + kfree_skb(skb); +} + +/* + * State machine for state 2, Awaiting Release State. + * The handling of the timer(s) is in file lapb_timer.c + */ +static void lapb_state2_machine(struct lapb_cb *lapb, struct sk_buff *skb, + struct lapb_frame *frame) +{ + switch (frame->type) { + case LAPB_SABM: + case LAPB_SABME: + lapb_dbg(1, "(%p) S2 RX {SABM,SABME}(%d)\n", + lapb->dev, frame->pf); + lapb_dbg(1, "(%p) S2 TX DM(%d)\n", lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, LAPB_RESPONSE); + break; + + case LAPB_DISC: + lapb_dbg(1, "(%p) S2 RX DISC(%d)\n", lapb->dev, frame->pf); + lapb_dbg(1, "(%p) S2 TX UA(%d)\n", lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_UA, frame->pf, LAPB_RESPONSE); + break; + + case LAPB_UA: + lapb_dbg(1, "(%p) S2 RX UA(%d)\n", lapb->dev, frame->pf); + if (frame->pf) { + lapb_dbg(0, "(%p) S2 -> S0\n", lapb->dev); + lapb->state = LAPB_STATE_0; + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb_disconnect_confirmation(lapb, LAPB_OK); + } + break; + + case LAPB_DM: + lapb_dbg(1, "(%p) S2 RX DM(%d)\n", lapb->dev, frame->pf); + if (frame->pf) { + lapb_dbg(0, "(%p) S2 -> S0\n", lapb->dev); + lapb->state = LAPB_STATE_0; + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb_disconnect_confirmation(lapb, LAPB_NOTCONNECTED); + } + break; + + case LAPB_I: + case LAPB_REJ: + case LAPB_RNR: + case LAPB_RR: + lapb_dbg(1, "(%p) S2 RX {I,REJ,RNR,RR}(%d)\n", + lapb->dev, frame->pf); + lapb_dbg(1, "(%p) S2 RX DM(%d)\n", lapb->dev, frame->pf); + if (frame->pf) + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + break; + } + + kfree_skb(skb); +} + +/* + * State machine for state 3, Connected State. + * The handling of the timer(s) is in file lapb_timer.c + */ +static void lapb_state3_machine(struct lapb_cb *lapb, struct sk_buff *skb, + struct lapb_frame *frame) +{ + int queued = 0; + int modulus = (lapb->mode & LAPB_EXTENDED) ? LAPB_EMODULUS : + LAPB_SMODULUS; + + switch (frame->type) { + case LAPB_SABM: + lapb_dbg(1, "(%p) S3 RX SABM(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S3 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } else { + lapb_dbg(1, "(%p) S3 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->condition = 0x00; + lapb->n2count = 0; + lapb->vs = 0; + lapb->vr = 0; + lapb->va = 0; + lapb_requeue_frames(lapb); + } + break; + + case LAPB_SABME: + lapb_dbg(1, "(%p) S3 RX SABME(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S3 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->condition = 0x00; + lapb->n2count = 0; + lapb->vs = 0; + lapb->vr = 0; + lapb->va = 0; + lapb_requeue_frames(lapb); + } else { + lapb_dbg(1, "(%p) S3 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } + break; + + case LAPB_DISC: + lapb_dbg(1, "(%p) S3 RX DISC(%d)\n", lapb->dev, frame->pf); + lapb_dbg(0, "(%p) S3 -> S0\n", lapb->dev); + lapb_clear_queues(lapb); + lapb_send_control(lapb, LAPB_UA, frame->pf, LAPB_RESPONSE); + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_0; + lapb_disconnect_indication(lapb, LAPB_OK); + break; + + case LAPB_DM: + lapb_dbg(1, "(%p) S3 RX DM(%d)\n", lapb->dev, frame->pf); + lapb_dbg(0, "(%p) S3 -> S0\n", lapb->dev); + lapb_clear_queues(lapb); + lapb->state = LAPB_STATE_0; + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb_disconnect_indication(lapb, LAPB_NOTCONNECTED); + break; + + case LAPB_RNR: + lapb_dbg(1, "(%p) S3 RX RNR(%d) R%d\n", + lapb->dev, frame->pf, frame->nr); + lapb->condition |= LAPB_PEER_RX_BUSY_CONDITION; + lapb_check_need_response(lapb, frame->cr, frame->pf); + if (lapb_validate_nr(lapb, frame->nr)) { + lapb_check_iframes_acked(lapb, frame->nr); + } else { + lapb->frmr_data = *frame; + lapb->frmr_type = LAPB_FRMR_Z; + lapb_transmit_frmr(lapb); + lapb_dbg(0, "(%p) S3 -> S4\n", lapb->dev); + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_4; + lapb->n2count = 0; + } + break; + + case LAPB_RR: + lapb_dbg(1, "(%p) S3 RX RR(%d) R%d\n", + lapb->dev, frame->pf, frame->nr); + lapb->condition &= ~LAPB_PEER_RX_BUSY_CONDITION; + lapb_check_need_response(lapb, frame->cr, frame->pf); + if (lapb_validate_nr(lapb, frame->nr)) { + lapb_check_iframes_acked(lapb, frame->nr); + } else { + lapb->frmr_data = *frame; + lapb->frmr_type = LAPB_FRMR_Z; + lapb_transmit_frmr(lapb); + lapb_dbg(0, "(%p) S3 -> S4\n", lapb->dev); + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_4; + lapb->n2count = 0; + } + break; + + case LAPB_REJ: + lapb_dbg(1, "(%p) S3 RX REJ(%d) R%d\n", + lapb->dev, frame->pf, frame->nr); + lapb->condition &= ~LAPB_PEER_RX_BUSY_CONDITION; + lapb_check_need_response(lapb, frame->cr, frame->pf); + if (lapb_validate_nr(lapb, frame->nr)) { + lapb_frames_acked(lapb, frame->nr); + lapb_stop_t1timer(lapb); + lapb->n2count = 0; + lapb_requeue_frames(lapb); + } else { + lapb->frmr_data = *frame; + lapb->frmr_type = LAPB_FRMR_Z; + lapb_transmit_frmr(lapb); + lapb_dbg(0, "(%p) S3 -> S4\n", lapb->dev); + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_4; + lapb->n2count = 0; + } + break; + + case LAPB_I: + lapb_dbg(1, "(%p) S3 RX I(%d) S%d R%d\n", + lapb->dev, frame->pf, frame->ns, frame->nr); + if (!lapb_validate_nr(lapb, frame->nr)) { + lapb->frmr_data = *frame; + lapb->frmr_type = LAPB_FRMR_Z; + lapb_transmit_frmr(lapb); + lapb_dbg(0, "(%p) S3 -> S4\n", lapb->dev); + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_4; + lapb->n2count = 0; + break; + } + if (lapb->condition & LAPB_PEER_RX_BUSY_CONDITION) + lapb_frames_acked(lapb, frame->nr); + else + lapb_check_iframes_acked(lapb, frame->nr); + + if (frame->ns == lapb->vr) { + int cn; + cn = lapb_data_indication(lapb, skb); + queued = 1; + /* + * If upper layer has dropped the frame, we + * basically ignore any further protocol + * processing. This will cause the peer + * to re-transmit the frame later like + * a frame lost on the wire. + */ + if (cn == NET_RX_DROP) { + pr_debug("rx congestion\n"); + break; + } + lapb->vr = (lapb->vr + 1) % modulus; + lapb->condition &= ~LAPB_REJECT_CONDITION; + if (frame->pf) + lapb_enquiry_response(lapb); + else { + if (!(lapb->condition & + LAPB_ACK_PENDING_CONDITION)) { + lapb->condition |= LAPB_ACK_PENDING_CONDITION; + lapb_start_t2timer(lapb); + } + } + } else { + if (lapb->condition & LAPB_REJECT_CONDITION) { + if (frame->pf) + lapb_enquiry_response(lapb); + } else { + lapb_dbg(1, "(%p) S3 TX REJ(%d) R%d\n", + lapb->dev, frame->pf, lapb->vr); + lapb->condition |= LAPB_REJECT_CONDITION; + lapb_send_control(lapb, LAPB_REJ, frame->pf, + LAPB_RESPONSE); + lapb->condition &= ~LAPB_ACK_PENDING_CONDITION; + } + } + break; + + case LAPB_FRMR: + lapb_dbg(1, "(%p) S3 RX FRMR(%d) %02X %02X %02X %02X %02X\n", + lapb->dev, frame->pf, + skb->data[0], skb->data[1], skb->data[2], + skb->data[3], skb->data[4]); + lapb_establish_data_link(lapb); + lapb_dbg(0, "(%p) S3 -> S1\n", lapb->dev); + lapb_requeue_frames(lapb); + lapb->state = LAPB_STATE_1; + break; + + case LAPB_ILLEGAL: + lapb_dbg(1, "(%p) S3 RX ILLEGAL(%d)\n", lapb->dev, frame->pf); + lapb->frmr_data = *frame; + lapb->frmr_type = LAPB_FRMR_W; + lapb_transmit_frmr(lapb); + lapb_dbg(0, "(%p) S3 -> S4\n", lapb->dev); + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_4; + lapb->n2count = 0; + break; + } + + if (!queued) + kfree_skb(skb); +} + +/* + * State machine for state 4, Frame Reject State. + * The handling of the timer(s) is in file lapb_timer.c. + */ +static void lapb_state4_machine(struct lapb_cb *lapb, struct sk_buff *skb, + struct lapb_frame *frame) +{ + switch (frame->type) { + case LAPB_SABM: + lapb_dbg(1, "(%p) S4 RX SABM(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S4 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } else { + lapb_dbg(1, "(%p) S4 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_dbg(0, "(%p) S4 -> S3\n", lapb->dev); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_3; + lapb->condition = 0x00; + lapb->n2count = 0; + lapb->vs = 0; + lapb->vr = 0; + lapb->va = 0; + lapb_connect_indication(lapb, LAPB_OK); + } + break; + + case LAPB_SABME: + lapb_dbg(1, "(%p) S4 RX SABME(%d)\n", lapb->dev, frame->pf); + if (lapb->mode & LAPB_EXTENDED) { + lapb_dbg(1, "(%p) S4 TX UA(%d)\n", + lapb->dev, frame->pf); + lapb_dbg(0, "(%p) S4 -> S3\n", lapb->dev); + lapb_send_control(lapb, LAPB_UA, frame->pf, + LAPB_RESPONSE); + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_3; + lapb->condition = 0x00; + lapb->n2count = 0; + lapb->vs = 0; + lapb->vr = 0; + lapb->va = 0; + lapb_connect_indication(lapb, LAPB_OK); + } else { + lapb_dbg(1, "(%p) S4 TX DM(%d)\n", + lapb->dev, frame->pf); + lapb_send_control(lapb, LAPB_DM, frame->pf, + LAPB_RESPONSE); + } + break; + } + + kfree_skb(skb); +} + +/* + * Process an incoming LAPB frame + */ +void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *skb) +{ + struct lapb_frame frame; + + if (lapb_decode(lapb, skb, &frame) < 0) { + kfree_skb(skb); + return; + } + + switch (lapb->state) { + case LAPB_STATE_0: + lapb_state0_machine(lapb, skb, &frame); break; + case LAPB_STATE_1: + lapb_state1_machine(lapb, skb, &frame); break; + case LAPB_STATE_2: + lapb_state2_machine(lapb, skb, &frame); break; + case LAPB_STATE_3: + lapb_state3_machine(lapb, skb, &frame); break; + case LAPB_STATE_4: + lapb_state4_machine(lapb, skb, &frame); break; + } + + lapb_kick(lapb); +} -- cgit v1.2.3-54-g00ecf