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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [net/] [x25/] [x25_in.c] - Blame information for rev 1765

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/*
 *      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 <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 <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/ip.h>                     /* For ip_rcv */
#include <asm/segment.h>
#include <asm/system.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <net/x25.h>
 
static int x25_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more)
{
        struct sk_buff *skbo, *skbn = skb;
 
        if (more) {
                sk->protinfo.x25->fraglen += skb->len;
                skb_queue_tail(&sk->protinfo.x25->fragment_queue, skb);
                skb_set_owner_r(skb, sk);
                return 0;
        }
 
        if (!more && sk->protinfo.x25->fraglen > 0) {    /* End of fragment */
                int len = sk->protinfo.x25->fraglen + skb->len;
 
                if ((skbn = alloc_skb(len, GFP_ATOMIC)) == NULL){
                        kfree_skb(skb);
                        return 1;
                }
 
                skb_queue_tail(&sk->protinfo.x25->fragment_queue, skb);
 
                skbn->h.raw = skbn->data;
 
                skbo = skb_dequeue(&sk->protinfo.x25->fragment_queue);
                memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);
                kfree_skb(skbo);
 
                while ((skbo = skb_dequeue(&sk->protinfo.x25->fragment_queue)) != NULL) {
                        skb_pull(skbo, (sk->protinfo.x25->neighbour->extended) ? X25_EXT_MIN_LEN : X25_STD_MIN_LEN);
                        memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);
                        kfree_skb(skbo);
                }
 
                sk->protinfo.x25->fraglen = 0;
        }
 
        skb_set_owner_r(skbn, sk);
        skb_queue_tail(&sk->receive_queue, skbn);
        if (!sk->dead)
                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)
{
        x25_address source_addr, dest_addr;
 
        switch (frametype) {
 
                case X25_CALL_ACCEPTED:
                        x25_stop_timer(sk);
                        sk->protinfo.x25->condition = 0x00;
                        sk->protinfo.x25->vs        = 0;
                        sk->protinfo.x25->va        = 0;
                        sk->protinfo.x25->vr        = 0;
                        sk->protinfo.x25->vl        = 0;
                        sk->protinfo.x25->state     = X25_STATE_3;
                        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, &sk->protinfo.x25->facilities, &sk->protinfo.x25->vc_facil_mask));
                        /*
                         *      Copy any Call User Data.
                         */
                        if (skb->len >= 0) {
                                memcpy(sk->protinfo.x25->calluserdata.cuddata, skb->data, skb->len);
                                sk->protinfo.x25->calluserdata.cudlength = skb->len;
                        }
                        if (!sk->dead)
                                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;
 
        modulus = (sk->protinfo.x25->neighbour->extended) ? X25_EMODULUS : X25_SMODULUS;
 
        switch (frametype) {
 
                case X25_RESET_REQUEST:
                        x25_write_internal(sk, X25_RESET_CONFIRMATION);
                        x25_stop_timer(sk);
                        sk->protinfo.x25->condition = 0x00;
                        sk->protinfo.x25->vs        = 0;
                        sk->protinfo.x25->vr        = 0;
                        sk->protinfo.x25->va        = 0;
                        sk->protinfo.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);
                                sk->protinfo.x25->condition = 0x00;
                                sk->protinfo.x25->vs        = 0;
                                sk->protinfo.x25->vr        = 0;
                                sk->protinfo.x25->va        = 0;
                                sk->protinfo.x25->vl        = 0;
                                sk->protinfo.x25->state     = X25_STATE_4;
                        } else {
                                x25_frames_acked(sk, nr);
                                if (frametype == X25_RNR) {
                                        sk->protinfo.x25->condition |= X25_COND_PEER_RX_BUSY;
                                } else {
                                        sk->protinfo.x25->condition &= ~X25_COND_PEER_RX_BUSY;
                                }
                        }
                        break;
 
                case X25_DATA:  /* XXX */
                        sk->protinfo.x25->condition &= ~X25_COND_PEER_RX_BUSY;
                        if ((ns!=sk->protinfo.x25->vr) ||
                            !x25_validate_nr(sk, nr)) {
                                x25_clear_queues(sk);
                                x25_write_internal(sk, X25_RESET_REQUEST);
                                x25_start_t22timer(sk);
                                sk->protinfo.x25->condition = 0x00;
                                sk->protinfo.x25->vs        = 0;
                                sk->protinfo.x25->vr        = 0;
                                sk->protinfo.x25->va        = 0;
                                sk->protinfo.x25->vl        = 0;
                                sk->protinfo.x25->state     = X25_STATE_4;
                                break;
                        }
                        x25_frames_acked(sk, nr);
                        if (ns == sk->protinfo.x25->vr) {
                                if (x25_queue_rx_frame(sk, skb, m) == 0) {
                                        sk->protinfo.x25->vr = (sk->protinfo.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);
                                        sk->protinfo.x25->condition = 0x00;
                                        sk->protinfo.x25->vs        = 0;
                                        sk->protinfo.x25->vr        = 0;
                                        sk->protinfo.x25->va        = 0;
                                        sk->protinfo.x25->vl        = 0;
                                        sk->protinfo.x25->state     = X25_STATE_4;
                                        break;
                                }
                                if (atomic_read(&sk->rmem_alloc) > (sk->rcvbuf / 2))
                                        sk->protinfo.x25->condition |= X25_COND_OWN_RX_BUSY;
                        }
                        /*
                         *      If the window is full Ack it immediately, else
                         *      start the holdback timer.
                         */
                        if (((sk->protinfo.x25->vl + sk->protinfo.x25->facilities.winsize_in) % modulus) == sk->protinfo.x25->vr) {
                                sk->protinfo.x25->condition &= ~X25_COND_ACK_PENDING;
                                x25_stop_timer(sk);
                                x25_enquiry_response(sk);
                        } else {
                                sk->protinfo.x25->condition |= X25_COND_ACK_PENDING;
                                x25_start_t2timer(sk);
                        }
                        break;
 
                case X25_INTERRUPT_CONFIRMATION:
                        sk->protinfo.x25->intflag = 0;
                        break;
 
                case X25_INTERRUPT:
                        if (sk->urginline) {
                                queued = (sock_queue_rcv_skb(sk, skb) == 0);
                        } else {
                                skb_set_owner_r(skb, sk);
                                skb_queue_tail(&sk->protinfo.x25->interrupt_in_queue, skb);
                                queued = 1;
                        }
                        if (sk->proc != 0) {
                                if (sk->proc > 0)
                                        kill_proc(sk->proc, SIGURG, 1);
                                else
                                        kill_pg(-sk->proc, SIGURG, 1);
                                sock_wake_async(sk->socket, 3, POLL_PRI);
                        }
                        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:
                        x25_stop_timer(sk);
                        sk->protinfo.x25->condition = 0x00;
                        sk->protinfo.x25->va        = 0;
                        sk->protinfo.x25->vr        = 0;
                        sk->protinfo.x25->vs        = 0;
                        sk->protinfo.x25->vl        = 0;
                        sk->protinfo.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)
{
        int queued = 0, frametype, ns, nr, q, d, m;
 
        if (sk->protinfo.x25->state == X25_STATE_0)
                return 0;
 
        frametype = x25_decode(sk, skb, &ns, &nr, &q, &d, &m);
 
        switch (sk->protinfo.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;
 
        queued = x25_process_rx_frame(sk,skb);
        if(!queued) kfree_skb(skb);
 
        return 0;
}

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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [net/] [x25/] [x25_in.c] - Blame information for rev 1765

Line No.	Rev	Author	Line
1	1275	phoenix	`/*`
2			`* X.25 Packet Layer release 002`
3			`*`
4			`* This is ALPHA test software. This code may break your machine, randomly fail to work with new`
5			`* releases, misbehave and/or generally screw up. It might even work.`
6			`*`
7			`* This code REQUIRES 2.1.15 or higher`
8			`*`
9			`* This module:`
10			`* This module is free software; you can redistribute it and/or`
11			`* modify it under the terms of the GNU General Public License`
12			`* as published by the Free Software Foundation; either version`
13			`* 2 of the License, or (at your option) any later version.`
14			`*`
15			`* History`
16			`* X.25 001 Jonathan Naylor Started coding.`
17			`* X.25 002 Jonathan Naylor Centralised disconnection code.`
18			`* New timer architecture.`
19			`* 2000-03-20 Daniela Squassoni Disabling/enabling of facilities`
20			`* negotiation.`
21			`* 2000-11-10 Henner Eisen Check and reset for out-of-sequence`
22			`* i-frames.`
23			`*/`
24
25			`#include <linux/errno.h>`
26			`#include <linux/types.h>`
27			`#include <linux/socket.h>`
28			`#include <linux/in.h>`
29			`#include <linux/kernel.h>`
30			`#include <linux/sched.h>`
31			`#include <linux/timer.h>`
32			`#include <linux/string.h>`
33			`#include <linux/sockios.h>`
34			`#include <linux/net.h>`
35			`#include <linux/inet.h>`
36			`#include <linux/netdevice.h>`
37			`#include <linux/skbuff.h>`
38			`#include <net/sock.h>`
39			`#include <net/ip.h> /* For ip_rcv */`
40			`#include <asm/segment.h>`
41			`#include <asm/system.h>`
42			`#include <linux/fcntl.h>`
43			`#include <linux/mm.h>`
44			`#include <linux/interrupt.h>`
45			`#include <net/x25.h>`
46
47			`static int x25_queue_rx_frame(struct sock sk, struct sk_buff skb, int more)`
48			`{`
49			`struct sk_buff skbo, skbn = skb;`
50
51			`if (more) {`
52			`sk->protinfo.x25->fraglen += skb->len;`
53			`skb_queue_tail(&sk->protinfo.x25->fragment_queue, skb);`
54			`skb_set_owner_r(skb, sk);`
55			`return 0;`
56			`}`
57
58			`if (!more && sk->protinfo.x25->fraglen > 0) { /* End of fragment */`
59			`int len = sk->protinfo.x25->fraglen + skb->len;`
60
61			`if ((skbn = alloc_skb(len, GFP_ATOMIC)) == NULL){`
62			`kfree_skb(skb);`
63			`return 1;`
64			`}`
65
66			`skb_queue_tail(&sk->protinfo.x25->fragment_queue, skb);`
67
68			`skbn->h.raw = skbn->data;`
69
70			`skbo = skb_dequeue(&sk->protinfo.x25->fragment_queue);`
71			`memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);`
72			`kfree_skb(skbo);`
73
74			`while ((skbo = skb_dequeue(&sk->protinfo.x25->fragment_queue)) != NULL) {`
75			`skb_pull(skbo, (sk->protinfo.x25->neighbour->extended) ? X25_EXT_MIN_LEN : X25_STD_MIN_LEN);`
76			`memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);`
77			`kfree_skb(skbo);`
78			`}`
79
80			`sk->protinfo.x25->fraglen = 0;`
81			`}`
82
83			`skb_set_owner_r(skbn, sk);`
84			`skb_queue_tail(&sk->receive_queue, skbn);`
85			`if (!sk->dead)`
86			`sk->data_ready(sk,skbn->len);`
87
88			`return 0;`
89			`}`
90
91			`/*`
92			`* State machine for state 1, Awaiting Call Accepted State.`
93			`* The handling of the timer(s) is in file x25_timer.c.`
94			`* Handling of state 0 and connection release is in af_x25.c.`
95			`*/`
96			`static int x25_state1_machine(struct sock sk, struct sk_buff skb, int frametype)`
97			`{`
98			`x25_address source_addr, dest_addr;`
99
100			`switch (frametype) {`
101
102			`case X25_CALL_ACCEPTED:`
103			`x25_stop_timer(sk);`
104			`sk->protinfo.x25->condition = 0x00;`
105			`sk->protinfo.x25->vs = 0;`
106			`sk->protinfo.x25->va = 0;`
107			`sk->protinfo.x25->vr = 0;`
108			`sk->protinfo.x25->vl = 0;`
109			`sk->protinfo.x25->state = X25_STATE_3;`
110			`sk->state = TCP_ESTABLISHED;`
111			`/*`
112			`* Parse the data in the frame.`
113			`*/`
114			`skb_pull(skb, X25_STD_MIN_LEN);`
115			`skb_pull(skb, x25_addr_ntoa(skb->data, &source_addr, &dest_addr));`
116			`skb_pull(skb, x25_parse_facilities(skb, &sk->protinfo.x25->facilities, &sk->protinfo.x25->vc_facil_mask));`
117			`/*`
118			`* Copy any Call User Data.`
119			`*/`
120			`if (skb->len >= 0) {`
121			`memcpy(sk->protinfo.x25->calluserdata.cuddata, skb->data, skb->len);`
122			`sk->protinfo.x25->calluserdata.cudlength = skb->len;`
123			`}`
124			`if (!sk->dead)`
125			`sk->state_change(sk);`
126			`break;`
127
128			`case X25_CLEAR_REQUEST:`
129			`x25_write_internal(sk, X25_CLEAR_CONFIRMATION);`
130			`x25_disconnect(sk, ECONNREFUSED, skb->data[3], skb->data[4]);`
131			`break;`
132
133			`default:`
134			`break;`
135			`}`
136
137			`return 0;`
138			`}`
139
140			`/*`
141			`* State machine for state 2, Awaiting Clear Confirmation State.`
142			`* The handling of the timer(s) is in file x25_timer.c`
143			`* Handling of state 0 and connection release is in af_x25.c.`
144			`*/`
145			`static int x25_state2_machine(struct sock sk, struct sk_buff skb, int frametype)`
146			`{`
147			`switch (frametype) {`
148
149			`case X25_CLEAR_REQUEST:`
150			`x25_write_internal(sk, X25_CLEAR_CONFIRMATION);`
151			`x25_disconnect(sk, 0, skb->data[3], skb->data[4]);`
152			`break;`
153
154			`case X25_CLEAR_CONFIRMATION:`
155			`x25_disconnect(sk, 0, 0, 0);`
156			`break;`
157
158			`default:`
159			`break;`
160			`}`
161
162			`return 0;`
163			`}`
164
165			`/*`
166			`* State machine for state 3, Connected State.`
167			`* The handling of the timer(s) is in file x25_timer.c`
168			`* Handling of state 0 and connection release is in af_x25.c.`
169			`*/`
170			`static int x25_state3_machine(struct sock sk, struct sk_buff skb, int frametype, int ns, int nr, int q, int d, int m)`
171			`{`
172			`int queued = 0;`
173			`int modulus;`
174
175			`modulus = (sk->protinfo.x25->neighbour->extended) ? X25_EMODULUS : X25_SMODULUS;`
176
177			`switch (frametype) {`
178
179			`case X25_RESET_REQUEST:`
180			`x25_write_internal(sk, X25_RESET_CONFIRMATION);`
181			`x25_stop_timer(sk);`
182			`sk->protinfo.x25->condition = 0x00;`
183			`sk->protinfo.x25->vs = 0;`
184			`sk->protinfo.x25->vr = 0;`
185			`sk->protinfo.x25->va = 0;`
186			`sk->protinfo.x25->vl = 0;`
187			`x25_requeue_frames(sk);`
188			`break;`
189
190			`case X25_CLEAR_REQUEST:`
191			`x25_write_internal(sk, X25_CLEAR_CONFIRMATION);`
192			`x25_disconnect(sk, 0, skb->data[3], skb->data[4]);`
193			`break;`
194
195			`case X25_RR:`
196			`case X25_RNR:`
197			`if (!x25_validate_nr(sk, nr)) {`
198			`x25_clear_queues(sk);`
199			`x25_write_internal(sk, X25_RESET_REQUEST);`
200			`x25_start_t22timer(sk);`
201			`sk->protinfo.x25->condition = 0x00;`
202			`sk->protinfo.x25->vs = 0;`
203			`sk->protinfo.x25->vr = 0;`
204			`sk->protinfo.x25->va = 0;`
205			`sk->protinfo.x25->vl = 0;`
206			`sk->protinfo.x25->state = X25_STATE_4;`
207			`} else {`
208			`x25_frames_acked(sk, nr);`
209			`if (frametype == X25_RNR) {`
210			`sk->protinfo.x25->condition \|= X25_COND_PEER_RX_BUSY;`
211			`} else {`
212			`sk->protinfo.x25->condition &= ~X25_COND_PEER_RX_BUSY;`
213			`}`
214			`}`
215			`break;`
216
217			`case X25_DATA: /* XXX */`
218			`sk->protinfo.x25->condition &= ~X25_COND_PEER_RX_BUSY;`
219			`if ((ns!=sk->protinfo.x25->vr) \|\|`
220			`!x25_validate_nr(sk, nr)) {`
221			`x25_clear_queues(sk);`
222			`x25_write_internal(sk, X25_RESET_REQUEST);`
223			`x25_start_t22timer(sk);`
224			`sk->protinfo.x25->condition = 0x00;`
225			`sk->protinfo.x25->vs = 0;`
226			`sk->protinfo.x25->vr = 0;`
227			`sk->protinfo.x25->va = 0;`
228			`sk->protinfo.x25->vl = 0;`
229			`sk->protinfo.x25->state = X25_STATE_4;`
230			`break;`
231			`}`
232			`x25_frames_acked(sk, nr);`
233			`if (ns == sk->protinfo.x25->vr) {`
234			`if (x25_queue_rx_frame(sk, skb, m) == 0) {`
235			`sk->protinfo.x25->vr = (sk->protinfo.x25->vr + 1) % modulus;`
236			`queued = 1;`
237			`} else {`
238			`/* Should never happen */`
239			`x25_clear_queues(sk);`
240			`x25_write_internal(sk, X25_RESET_REQUEST);`
241			`x25_start_t22timer(sk);`
242			`sk->protinfo.x25->condition = 0x00;`
243			`sk->protinfo.x25->vs = 0;`
244			`sk->protinfo.x25->vr = 0;`
245			`sk->protinfo.x25->va = 0;`
246			`sk->protinfo.x25->vl = 0;`
247			`sk->protinfo.x25->state = X25_STATE_4;`
248			`break;`
249			`}`
250			`if (atomic_read(&sk->rmem_alloc) > (sk->rcvbuf / 2))`
251			`sk->protinfo.x25->condition \|= X25_COND_OWN_RX_BUSY;`
252			`}`
253			`/*`
254			`* If the window is full Ack it immediately, else`
255			`* start the holdback timer.`
256			`*/`
257			`if (((sk->protinfo.x25->vl + sk->protinfo.x25->facilities.winsize_in) % modulus) == sk->protinfo.x25->vr) {`
258			`sk->protinfo.x25->condition &= ~X25_COND_ACK_PENDING;`
259			`x25_stop_timer(sk);`
260			`x25_enquiry_response(sk);`
261			`} else {`
262			`sk->protinfo.x25->condition \|= X25_COND_ACK_PENDING;`
263			`x25_start_t2timer(sk);`
264			`}`
265			`break;`
266
267			`case X25_INTERRUPT_CONFIRMATION:`
268			`sk->protinfo.x25->intflag = 0;`
269			`break;`
270
271			`case X25_INTERRUPT:`
272			`if (sk->urginline) {`
273			`queued = (sock_queue_rcv_skb(sk, skb) == 0);`
274			`} else {`
275			`skb_set_owner_r(skb, sk);`
276			`skb_queue_tail(&sk->protinfo.x25->interrupt_in_queue, skb);`
277			`queued = 1;`
278			`}`
279			`if (sk->proc != 0) {`
280			`if (sk->proc > 0)`
281			`kill_proc(sk->proc, SIGURG, 1);`
282			`else`
283			`kill_pg(-sk->proc, SIGURG, 1);`
284			`sock_wake_async(sk->socket, 3, POLL_PRI);`
285			`}`
286			`x25_write_internal(sk, X25_INTERRUPT_CONFIRMATION);`
287			`break;`
288
289			`default:`
290			`printk(KERN_WARNING "x25: unknown %02X in state 3\n", frametype);`
291			`break;`
292			`}`
293
294			`return queued;`
295			`}`
296
297			`/*`
298			`* State machine for state 4, Awaiting Reset Confirmation State.`
299			`* The handling of the timer(s) is in file x25_timer.c`
300			`* Handling of state 0 and connection release is in af_x25.c.`
301			`*/`
302			`static int x25_state4_machine(struct sock sk, struct sk_buff skb, int frametype)`
303			`{`
304			`switch (frametype) {`
305
306			`case X25_RESET_REQUEST:`
307			`x25_write_internal(sk, X25_RESET_CONFIRMATION);`
308			`case X25_RESET_CONFIRMATION:`
309			`x25_stop_timer(sk);`
310			`sk->protinfo.x25->condition = 0x00;`
311			`sk->protinfo.x25->va = 0;`
312			`sk->protinfo.x25->vr = 0;`
313			`sk->protinfo.x25->vs = 0;`
314			`sk->protinfo.x25->vl = 0;`
315			`sk->protinfo.x25->state = X25_STATE_3;`
316			`x25_requeue_frames(sk);`
317			`break;`
318
319			`case X25_CLEAR_REQUEST:`
320			`x25_write_internal(sk, X25_CLEAR_CONFIRMATION);`
321			`x25_disconnect(sk, 0, skb->data[3], skb->data[4]);`
322			`break;`
323
324			`default:`
325			`break;`
326			`}`
327
328			`return 0;`
329			`}`
330
331			`/* Higher level upcall for a LAPB frame */`
332			`int x25_process_rx_frame(struct sock sk, struct sk_buff skb)`
333			`{`
334			`int queued = 0, frametype, ns, nr, q, d, m;`
335
336			`if (sk->protinfo.x25->state == X25_STATE_0)`
337			`return 0;`
338
339			`frametype = x25_decode(sk, skb, &ns, &nr, &q, &d, &m);`
340
341			`switch (sk->protinfo.x25->state) {`
342			`case X25_STATE_1:`
343			`queued = x25_state1_machine(sk, skb, frametype);`
344			`break;`
345			`case X25_STATE_2:`
346			`queued = x25_state2_machine(sk, skb, frametype);`
347			`break;`
348			`case X25_STATE_3:`
349			`queued = x25_state3_machine(sk, skb, frametype, ns, nr, q, d, m);`
350			`break;`
351			`case X25_STATE_4:`
352			`queued = x25_state4_machine(sk, skb, frametype);`
353			`break;`
354			`}`
355
356			`x25_kick(sk);`
357
358			`return queued;`
359			`}`
360
361			`int x25_backlog_rcv(struct sock sk, struct sk_buff skb)`
362			`{`
363			`int queued;`
364
365			`queued = x25_process_rx_frame(sk,skb);`
366			`if(!queued) kfree_skb(skb);`
367
368			`return 0;`
369			`}`