diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/rose/rose_in.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/rose/rose_in.c')
-rw-r--r-- | net/rose/rose_in.c | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/net/rose/rose_in.c b/net/rose/rose_in.c new file mode 100644 index 000000000000..ef475a1bb1ba --- /dev/null +++ b/net/rose/rose_in.c @@ -0,0 +1,297 @@ +/* + * 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. + * + * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + * + * Most of this code is based on the SDL diagrams published in the 7th ARRL + * Computer Networking Conference papers. The diagrams have mistakes in them, + * but are mostly correct. Before you modify the code could you read the SDL + * diagrams as the code is not obvious and probably very easy to break. + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/ip.h> /* For ip_rcv */ +#include <net/tcp.h> +#include <asm/system.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <net/rose.h> + +/* + * State machine for state 1, Awaiting Call Accepted State. + * The handling of the timer(s) is in file rose_timer.c. + * Handling of state 0 and connection release is in af_rose.c. + */ +static int rose_state1_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct rose_sock *rose = rose_sk(sk); + + switch (frametype) { + case ROSE_CALL_ACCEPTED: + rose_stop_timer(sk); + rose_start_idletimer(sk); + rose->condition = 0x00; + rose->vs = 0; + rose->va = 0; + rose->vr = 0; + rose->vl = 0; + rose->state = ROSE_STATE_3; + sk->sk_state = TCP_ESTABLISHED; + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_state_change(sk); + break; + + case ROSE_CLEAR_REQUEST: + rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION); + rose_disconnect(sk, ECONNREFUSED, skb->data[3], skb->data[4]); + rose->neighbour->use--; + break; + + default: + break; + } + + return 0; +} + +/* + * State machine for state 2, Awaiting Clear Confirmation State. + * The handling of the timer(s) is in file rose_timer.c + * Handling of state 0 and connection release is in af_rose.c. + */ +static int rose_state2_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct rose_sock *rose = rose_sk(sk); + + switch (frametype) { + case ROSE_CLEAR_REQUEST: + rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION); + rose_disconnect(sk, 0, skb->data[3], skb->data[4]); + rose->neighbour->use--; + break; + + case ROSE_CLEAR_CONFIRMATION: + rose_disconnect(sk, 0, -1, -1); + rose->neighbour->use--; + break; + + default: + break; + } + + return 0; +} + +/* + * State machine for state 3, Connected State. + * The handling of the timer(s) is in file rose_timer.c + * Handling of state 0 and connection release is in af_rose.c. + */ +static int rose_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype, int ns, int nr, int q, int d, int m) +{ + struct rose_sock *rose = rose_sk(sk); + int queued = 0; + + switch (frametype) { + case ROSE_RESET_REQUEST: + rose_stop_timer(sk); + rose_start_idletimer(sk); + rose_write_internal(sk, ROSE_RESET_CONFIRMATION); + rose->condition = 0x00; + rose->vs = 0; + rose->vr = 0; + rose->va = 0; + rose->vl = 0; + rose_requeue_frames(sk); + break; + + case ROSE_CLEAR_REQUEST: + rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION); + rose_disconnect(sk, 0, skb->data[3], skb->data[4]); + rose->neighbour->use--; + break; + + case ROSE_RR: + case ROSE_RNR: + if (!rose_validate_nr(sk, nr)) { + rose_write_internal(sk, ROSE_RESET_REQUEST); + rose->condition = 0x00; + rose->vs = 0; + rose->vr = 0; + rose->va = 0; + rose->vl = 0; + rose->state = ROSE_STATE_4; + rose_start_t2timer(sk); + rose_stop_idletimer(sk); + } else { + rose_frames_acked(sk, nr); + if (frametype == ROSE_RNR) { + rose->condition |= ROSE_COND_PEER_RX_BUSY; + } else { + rose->condition &= ~ROSE_COND_PEER_RX_BUSY; + } + } + break; + + case ROSE_DATA: /* XXX */ + rose->condition &= ~ROSE_COND_PEER_RX_BUSY; + if (!rose_validate_nr(sk, nr)) { + rose_write_internal(sk, ROSE_RESET_REQUEST); + rose->condition = 0x00; + rose->vs = 0; + rose->vr = 0; + rose->va = 0; + rose->vl = 0; + rose->state = ROSE_STATE_4; + rose_start_t2timer(sk); + rose_stop_idletimer(sk); + break; + } + rose_frames_acked(sk, nr); + if (ns == rose->vr) { + rose_start_idletimer(sk); + if (sock_queue_rcv_skb(sk, skb) == 0) { + rose->vr = (rose->vr + 1) % ROSE_MODULUS; + queued = 1; + } else { + /* Should never happen ! */ + rose_write_internal(sk, ROSE_RESET_REQUEST); + rose->condition = 0x00; + rose->vs = 0; + rose->vr = 0; + rose->va = 0; + rose->vl = 0; + rose->state = ROSE_STATE_4; + rose_start_t2timer(sk); + rose_stop_idletimer(sk); + break; + } + if (atomic_read(&sk->sk_rmem_alloc) > + (sk->sk_rcvbuf / 2)) + rose->condition |= ROSE_COND_OWN_RX_BUSY; + } + /* + * If the window is full, ack the frame, else start the + * acknowledge hold back timer. + */ + if (((rose->vl + sysctl_rose_window_size) % ROSE_MODULUS) == rose->vr) { + rose->condition &= ~ROSE_COND_ACK_PENDING; + rose_stop_timer(sk); + rose_enquiry_response(sk); + } else { + rose->condition |= ROSE_COND_ACK_PENDING; + rose_start_hbtimer(sk); + } + break; + + default: + printk(KERN_WARNING "ROSE: unknown %02X in state 3\n", frametype); + break; + } + + return queued; +} + +/* + * State machine for state 4, Awaiting Reset Confirmation State. + * The handling of the timer(s) is in file rose_timer.c + * Handling of state 0 and connection release is in af_rose.c. + */ +static int rose_state4_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct rose_sock *rose = rose_sk(sk); + + switch (frametype) { + case ROSE_RESET_REQUEST: + rose_write_internal(sk, ROSE_RESET_CONFIRMATION); + case ROSE_RESET_CONFIRMATION: + rose_stop_timer(sk); + rose_start_idletimer(sk); + rose->condition = 0x00; + rose->va = 0; + rose->vr = 0; + rose->vs = 0; + rose->vl = 0; + rose->state = ROSE_STATE_3; + rose_requeue_frames(sk); + break; + + case ROSE_CLEAR_REQUEST: + rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION); + rose_disconnect(sk, 0, skb->data[3], skb->data[4]); + rose->neighbour->use--; + break; + + default: + break; + } + + return 0; +} + +/* + * State machine for state 5, Awaiting Call Acceptance State. + * The handling of the timer(s) is in file rose_timer.c + * Handling of state 0 and connection release is in af_rose.c. + */ +static int rose_state5_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + if (frametype == ROSE_CLEAR_REQUEST) { + rose_write_internal(sk, ROSE_CLEAR_CONFIRMATION); + rose_disconnect(sk, 0, skb->data[3], skb->data[4]); + rose_sk(sk)->neighbour->use--; + } + + return 0; +} + +/* Higher level upcall for a LAPB frame */ +int rose_process_rx_frame(struct sock *sk, struct sk_buff *skb) +{ + struct rose_sock *rose = rose_sk(sk); + int queued = 0, frametype, ns, nr, q, d, m; + + if (rose->state == ROSE_STATE_0) + return 0; + + frametype = rose_decode(skb, &ns, &nr, &q, &d, &m); + + switch (rose->state) { + case ROSE_STATE_1: + queued = rose_state1_machine(sk, skb, frametype); + break; + case ROSE_STATE_2: + queued = rose_state2_machine(sk, skb, frametype); + break; + case ROSE_STATE_3: + queued = rose_state3_machine(sk, skb, frametype, ns, nr, q, d, m); + break; + case ROSE_STATE_4: + queued = rose_state4_machine(sk, skb, frametype); + break; + case ROSE_STATE_5: + queued = rose_state5_machine(sk, skb, frametype); + break; + } + + rose_kick(sk); + + return queued; +} |