From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-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! --- net/x25/x25_in.c | 361 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 361 insertions(+) create mode 100644 net/x25/x25_in.c (limited to 'net/x25/x25_in.c') diff --git a/net/x25/x25_in.c b/net/x25/x25_in.c new file mode 100644 index 00000000000..b0197c70a9f --- /dev/null +++ b/net/x25/x25_in.c @@ -0,0 +1,361 @@ +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * 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 + * X.25 001 Jonathan Naylor Started coding. + * X.25 002 Jonathan Naylor Centralised disconnection code. + * New timer architecture. + * 2000-03-20 Daniela Squassoni Disabling/enabling of facilities + * negotiation. + * 2000-11-10 Henner Eisen Check and reset for out-of-sequence + * i-frames. + */ + +#include +#include +#include +#include +#include +#include +#include + +static int x25_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more) +{ + struct sk_buff *skbo, *skbn = skb; + struct x25_sock *x25 = x25_sk(sk); + + if (more) { + x25->fraglen += skb->len; + skb_queue_tail(&x25->fragment_queue, skb); + skb_set_owner_r(skb, sk); + return 0; + } + + if (!more && x25->fraglen > 0) { /* End of fragment */ + int len = x25->fraglen + skb->len; + + if ((skbn = alloc_skb(len, GFP_ATOMIC)) == NULL){ + kfree_skb(skb); + return 1; + } + + skb_queue_tail(&x25->fragment_queue, skb); + + skbn->h.raw = skbn->data; + + skbo = skb_dequeue(&x25->fragment_queue); + memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len); + kfree_skb(skbo); + + while ((skbo = + skb_dequeue(&x25->fragment_queue)) != NULL) { + skb_pull(skbo, (x25->neighbour->extended) ? + X25_EXT_MIN_LEN : X25_STD_MIN_LEN); + memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len); + kfree_skb(skbo); + } + + x25->fraglen = 0; + } + + skb_set_owner_r(skbn, sk); + skb_queue_tail(&sk->sk_receive_queue, skbn); + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk, skbn->len); + + return 0; +} + +/* + * State machine for state 1, Awaiting Call Accepted State. + * The handling of the timer(s) is in file x25_timer.c. + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state1_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct x25_address source_addr, dest_addr; + + switch (frametype) { + case X25_CALL_ACCEPTED: { + struct x25_sock *x25 = x25_sk(sk); + + x25_stop_timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->va = 0; + x25->vr = 0; + x25->vl = 0; + x25->state = X25_STATE_3; + sk->sk_state = TCP_ESTABLISHED; + /* + * Parse the data in the frame. + */ + skb_pull(skb, X25_STD_MIN_LEN); + skb_pull(skb, x25_addr_ntoa(skb->data, &source_addr, &dest_addr)); + skb_pull(skb, + x25_parse_facilities(skb, &x25->facilities, + &x25->vc_facil_mask)); + /* + * Copy any Call User Data. + */ + if (skb->len >= 0) { + memcpy(x25->calluserdata.cuddata, skb->data, + skb->len); + x25->calluserdata.cudlength = skb->len; + } + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_state_change(sk); + break; + } + case X25_CLEAR_REQUEST: + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, ECONNREFUSED, skb->data[3], skb->data[4]); + break; + + default: + break; + } + + return 0; +} + +/* + * State machine for state 2, Awaiting Clear Confirmation State. + * The handling of the timer(s) is in file x25_timer.c + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state2_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + switch (frametype) { + + case X25_CLEAR_REQUEST: + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, 0, skb->data[3], skb->data[4]); + break; + + case X25_CLEAR_CONFIRMATION: + x25_disconnect(sk, 0, 0, 0); + break; + + default: + break; + } + + return 0; +} + +/* + * State machine for state 3, Connected State. + * The handling of the timer(s) is in file x25_timer.c + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype, int ns, int nr, int q, int d, int m) +{ + int queued = 0; + int modulus; + struct x25_sock *x25 = x25_sk(sk); + + modulus = (x25->neighbour->extended) ? X25_EMODULUS : X25_SMODULUS; + + switch (frametype) { + + case X25_RESET_REQUEST: + x25_write_internal(sk, X25_RESET_CONFIRMATION); + x25_stop_timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25_requeue_frames(sk); + break; + + case X25_CLEAR_REQUEST: + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, 0, skb->data[3], skb->data[4]); + break; + + case X25_RR: + case X25_RNR: + if (!x25_validate_nr(sk, nr)) { + x25_clear_queues(sk); + x25_write_internal(sk, X25_RESET_REQUEST); + x25_start_t22timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25->state = X25_STATE_4; + } else { + x25_frames_acked(sk, nr); + if (frametype == X25_RNR) { + x25->condition |= X25_COND_PEER_RX_BUSY; + } else { + x25->condition &= ~X25_COND_PEER_RX_BUSY; + } + } + break; + + case X25_DATA: /* XXX */ + x25->condition &= ~X25_COND_PEER_RX_BUSY; + if ((ns != x25->vr) || !x25_validate_nr(sk, nr)) { + x25_clear_queues(sk); + x25_write_internal(sk, X25_RESET_REQUEST); + x25_start_t22timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25->state = X25_STATE_4; + break; + } + x25_frames_acked(sk, nr); + if (ns == x25->vr) { + if (x25_queue_rx_frame(sk, skb, m) == 0) { + x25->vr = (x25->vr + 1) % modulus; + queued = 1; + } else { + /* Should never happen */ + x25_clear_queues(sk); + x25_write_internal(sk, X25_RESET_REQUEST); + x25_start_t22timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25->state = X25_STATE_4; + break; + } + if (atomic_read(&sk->sk_rmem_alloc) > + (sk->sk_rcvbuf / 2)) + x25->condition |= X25_COND_OWN_RX_BUSY; + } + /* + * If the window is full Ack it immediately, else + * start the holdback timer. + */ + if (((x25->vl + x25->facilities.winsize_in) % modulus) == x25->vr) { + x25->condition &= ~X25_COND_ACK_PENDING; + x25_stop_timer(sk); + x25_enquiry_response(sk); + } else { + x25->condition |= X25_COND_ACK_PENDING; + x25_start_t2timer(sk); + } + break; + + case X25_INTERRUPT_CONFIRMATION: + x25->intflag = 0; + break; + + case X25_INTERRUPT: + if (sock_flag(sk, SOCK_URGINLINE)) + queued = !sock_queue_rcv_skb(sk, skb); + else { + skb_set_owner_r(skb, sk); + skb_queue_tail(&x25->interrupt_in_queue, skb); + queued = 1; + } + sk_send_sigurg(sk); + x25_write_internal(sk, X25_INTERRUPT_CONFIRMATION); + break; + + default: + printk(KERN_WARNING "x25: 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 x25_timer.c + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state4_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + switch (frametype) { + + case X25_RESET_REQUEST: + x25_write_internal(sk, X25_RESET_CONFIRMATION); + case X25_RESET_CONFIRMATION: { + struct x25_sock *x25 = x25_sk(sk); + + x25_stop_timer(sk); + x25->condition = 0x00; + x25->va = 0; + x25->vr = 0; + x25->vs = 0; + x25->vl = 0; + x25->state = X25_STATE_3; + x25_requeue_frames(sk); + break; + } + case X25_CLEAR_REQUEST: + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, 0, skb->data[3], skb->data[4]); + break; + + default: + break; + } + + return 0; +} + +/* Higher level upcall for a LAPB frame */ +int x25_process_rx_frame(struct sock *sk, struct sk_buff *skb) +{ + struct x25_sock *x25 = x25_sk(sk); + int queued = 0, frametype, ns, nr, q, d, m; + + if (x25->state == X25_STATE_0) + return 0; + + frametype = x25_decode(sk, skb, &ns, &nr, &q, &d, &m); + + switch (x25->state) { + case X25_STATE_1: + queued = x25_state1_machine(sk, skb, frametype); + break; + case X25_STATE_2: + queued = x25_state2_machine(sk, skb, frametype); + break; + case X25_STATE_3: + queued = x25_state3_machine(sk, skb, frametype, ns, nr, q, d, m); + break; + case X25_STATE_4: + queued = x25_state4_machine(sk, skb, frametype); + break; + } + + x25_kick(sk); + + return queued; +} + +int x25_backlog_rcv(struct sock *sk, struct sk_buff *skb) +{ + int queued = x25_process_rx_frame(sk, skb); + + if (!queued) + kfree_skb(skb); + + return 0; +} -- cgit v1.2.3