OpenCores
URL https://opencores.org/ocsvn/test_project/test_project/trunk

Subversion Repositories test_project

[/] [test_project/] [trunk/] [linux_sd_driver/] [net/] [netrom/] [nr_in.c] - Blame information for rev 62

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 62 marcus.erl 
/*
2 
 * This program is free software; you can redistribute it and/or modify
3 
 * it under the terms of the GNU General Public License as published by
4 
 * the Free Software Foundation; either version 2 of the License, or
5 
 * (at your option) any later version.
6 
 *
7 
 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 
 * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
9 
 */
10 
#include <linux/errno.h>
11 
#include <linux/types.h>
12 
#include <linux/socket.h>
13 
#include <linux/in.h>
14 
#include <linux/kernel.h>
15 
#include <linux/timer.h>
16 
#include <linux/string.h>
17 
#include <linux/sockios.h>
18 
#include <linux/net.h>
19 
#include <net/ax25.h>
20 
#include <linux/inet.h>
21 
#include <linux/netdevice.h>
22 
#include <linux/skbuff.h>
23 
#include <net/sock.h>
24 
#include <net/tcp_states.h>
25 
#include <asm/uaccess.h>
26 
#include <asm/system.h>
27 
#include <linux/fcntl.h>
28 
#include <linux/mm.h>
29 
#include <linux/interrupt.h>
30 
#include <net/netrom.h>
31 
 
32 
static int nr_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more)
33 
{
34 
        struct sk_buff *skbo, *skbn = skb;
35 
        struct nr_sock *nr = nr_sk(sk);
36 
 
37 
        skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
38 
 
39 
        nr_start_idletimer(sk);
40 
 
41 
        if (more) {
42 
                nr->fraglen += skb->len;
43 
                skb_queue_tail(&nr->frag_queue, skb);
44 
                return 0;
45 
        }
46 
 
47 
        if (!more && nr->fraglen > 0) {  /* End of fragment */
48 
                nr->fraglen += skb->len;
49 
                skb_queue_tail(&nr->frag_queue, skb);
50 
 
51 
                if ((skbn = alloc_skb(nr->fraglen, GFP_ATOMIC)) == NULL)
52 
                        return 1;
53 
 
54 
                skb_reset_transport_header(skbn);
55 
 
56 
                while ((skbo = skb_dequeue(&nr->frag_queue)) != NULL) {
57 
                        skb_copy_from_linear_data(skbo,
58 
                                                  skb_put(skbn, skbo->len),
59 
                                                  skbo->len);
60 
                        kfree_skb(skbo);
61 
                }
62 
 
63 
                nr->fraglen = 0;
64 
        }
65 
 
66 
        return sock_queue_rcv_skb(sk, skbn);
67 
}
68 
 
69 
/*
70 
 * State machine for state 1, Awaiting Connection State.
71 
 * The handling of the timer(s) is in file nr_timer.c.
72 
 * Handling of state 0 and connection release is in netrom.c.
73 
 */
74 
static int nr_state1_machine(struct sock *sk, struct sk_buff *skb,
75 
        int frametype)
76 
{
77 
        switch (frametype) {
78 
        case NR_CONNACK: {
79 
                struct nr_sock *nr = nr_sk(sk);
80 
 
81 
                nr_stop_t1timer(sk);
82 
                nr_start_idletimer(sk);
83 
                nr->your_index = skb->data[17];
84 
                nr->your_id    = skb->data[18];
85 
                nr->vs         = 0;
86 
                nr->va         = 0;
87 
                nr->vr         = 0;
88 
                nr->vl         = 0;
89 
                nr->state      = NR_STATE_3;
90 
                nr->n2count    = 0;
91 
                nr->window     = skb->data[20];
92 
                sk->sk_state   = TCP_ESTABLISHED;
93 
                if (!sock_flag(sk, SOCK_DEAD))
94 
                        sk->sk_state_change(sk);
95 
                break;
96 
        }
97 
 
98 
        case NR_CONNACK | NR_CHOKE_FLAG:
99 
                nr_disconnect(sk, ECONNREFUSED);
100 
                break;
101 
 
102 
        case NR_RESET:
103 
                if (sysctl_netrom_reset_circuit)
104 
                        nr_disconnect(sk, ECONNRESET);
105 
                break;
106 
 
107 
        default:
108 
                break;
109 
        }
110 
        return 0;
111 
}
112 
 
113 
/*
114 
 * State machine for state 2, Awaiting Release State.
115 
 * The handling of the timer(s) is in file nr_timer.c
116 
 * Handling of state 0 and connection release is in netrom.c.
117 
 */
118 
static int nr_state2_machine(struct sock *sk, struct sk_buff *skb,
119 
        int frametype)
120 
{
121 
        switch (frametype) {
122 
        case NR_CONNACK | NR_CHOKE_FLAG:
123 
                nr_disconnect(sk, ECONNRESET);
124 
                break;
125 
 
126 
        case NR_DISCREQ:
127 
                nr_write_internal(sk, NR_DISCACK);
128 
 
129 
        case NR_DISCACK:
130 
                nr_disconnect(sk, 0);
131 
                break;
132 
 
133 
        case NR_RESET:
134 
                if (sysctl_netrom_reset_circuit)
135 
                        nr_disconnect(sk, ECONNRESET);
136 
                break;
137 
 
138 
        default:
139 
                break;
140 
        }
141 
        return 0;
142 
}
143 
 
144 
/*
145 
 * State machine for state 3, Connected State.
146 
 * The handling of the timer(s) is in file nr_timer.c
147 
 * Handling of state 0 and connection release is in netrom.c.
148 
 */
149 
static int nr_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype)
150 
{
151 
        struct nr_sock *nrom = nr_sk(sk);
152 
        struct sk_buff_head temp_queue;
153 
        struct sk_buff *skbn;
154 
        unsigned short save_vr;
155 
        unsigned short nr, ns;
156 
        int queued = 0;
157 
 
158 
        nr = skb->data[18];
159 
        ns = skb->data[17];
160 
 
161 
        switch (frametype) {
162 
        case NR_CONNREQ:
163 
                nr_write_internal(sk, NR_CONNACK);
164 
                break;
165 
 
166 
        case NR_DISCREQ:
167 
                nr_write_internal(sk, NR_DISCACK);
168 
                nr_disconnect(sk, 0);
169 
                break;
170 
 
171 
        case NR_CONNACK | NR_CHOKE_FLAG:
172 
        case NR_DISCACK:
173 
                nr_disconnect(sk, ECONNRESET);
174 
                break;
175 
 
176 
        case NR_INFOACK:
177 
        case NR_INFOACK | NR_CHOKE_FLAG:
178 
        case NR_INFOACK | NR_NAK_FLAG:
179 
        case NR_INFOACK | NR_NAK_FLAG | NR_CHOKE_FLAG:
180 
                if (frametype & NR_CHOKE_FLAG) {
181 
                        nrom->condition |= NR_COND_PEER_RX_BUSY;
182 
                        nr_start_t4timer(sk);
183 
                } else {
184 
                        nrom->condition &= ~NR_COND_PEER_RX_BUSY;
185 
                        nr_stop_t4timer(sk);
186 
                }
187 
                if (!nr_validate_nr(sk, nr)) {
188 
                        break;
189 
                }
190 
                if (frametype & NR_NAK_FLAG) {
191 
                        nr_frames_acked(sk, nr);
192 
                        nr_send_nak_frame(sk);
193 
                } else {
194 
                        if (nrom->condition & NR_COND_PEER_RX_BUSY) {
195 
                                nr_frames_acked(sk, nr);
196 
                        } else {
197 
                                nr_check_iframes_acked(sk, nr);
198 
                        }
199 
                }
200 
                break;
201 
 
202 
        case NR_INFO:
203 
        case NR_INFO | NR_NAK_FLAG:
204 
        case NR_INFO | NR_CHOKE_FLAG:
205 
        case NR_INFO | NR_MORE_FLAG:
206 
        case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG:
207 
        case NR_INFO | NR_CHOKE_FLAG | NR_MORE_FLAG:
208 
        case NR_INFO | NR_NAK_FLAG | NR_MORE_FLAG:
209 
        case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG | NR_MORE_FLAG:
210 
                if (frametype & NR_CHOKE_FLAG) {
211 
                        nrom->condition |= NR_COND_PEER_RX_BUSY;
212 
                        nr_start_t4timer(sk);
213 
                } else {
214 
                        nrom->condition &= ~NR_COND_PEER_RX_BUSY;
215 
                        nr_stop_t4timer(sk);
216 
                }
217 
                if (nr_validate_nr(sk, nr)) {
218 
                        if (frametype & NR_NAK_FLAG) {
219 
                                nr_frames_acked(sk, nr);
220 
                                nr_send_nak_frame(sk);
221 
                        } else {
222 
                                if (nrom->condition & NR_COND_PEER_RX_BUSY) {
223 
                                        nr_frames_acked(sk, nr);
224 
                                } else {
225 
                                        nr_check_iframes_acked(sk, nr);
226 
                                }
227 
                        }
228 
                }
229 
                queued = 1;
230 
                skb_queue_head(&nrom->reseq_queue, skb);
231 
                if (nrom->condition & NR_COND_OWN_RX_BUSY)
232 
                        break;
233 
                skb_queue_head_init(&temp_queue);
234 
                do {
235 
                        save_vr = nrom->vr;
236 
                        while ((skbn = skb_dequeue(&nrom->reseq_queue)) != NULL) {
237 
                                ns = skbn->data[17];
238 
                                if (ns == nrom->vr) {
239 
                                        if (nr_queue_rx_frame(sk, skbn, frametype & NR_MORE_FLAG) == 0) {
240 
                                                nrom->vr = (nrom->vr + 1) % NR_MODULUS;
241 
                                        } else {
242 
                                                nrom->condition |= NR_COND_OWN_RX_BUSY;
243 
                                                skb_queue_tail(&temp_queue, skbn);
244 
                                        }
245 
                                } else if (nr_in_rx_window(sk, ns)) {
246 
                                        skb_queue_tail(&temp_queue, skbn);
247 
                                } else {
248 
                                        kfree_skb(skbn);
249 
                                }
250 
                        }
251 
                        while ((skbn = skb_dequeue(&temp_queue)) != NULL) {
252 
                                skb_queue_tail(&nrom->reseq_queue, skbn);
253 
                        }
254 
                } while (save_vr != nrom->vr);
255 
                /*
256 
                 * Window is full, ack it immediately.
257 
                 */
258 
                if (((nrom->vl + nrom->window) % NR_MODULUS) == nrom->vr) {
259 
                        nr_enquiry_response(sk);
260 
                } else {
261 
                        if (!(nrom->condition & NR_COND_ACK_PENDING)) {
262 
                                nrom->condition |= NR_COND_ACK_PENDING;
263 
                                nr_start_t2timer(sk);
264 
                        }
265 
                }
266 
                break;
267 
 
268 
        case NR_RESET:
269 
                if (sysctl_netrom_reset_circuit)
270 
                        nr_disconnect(sk, ECONNRESET);
271 
                break;
272 
 
273 
        default:
274 
                break;
275 
        }
276 
        return queued;
277 
}
278 
 
279 
/* Higher level upcall for a LAPB frame - called with sk locked */
280 
int nr_process_rx_frame(struct sock *sk, struct sk_buff *skb)
281 
{
282 
        struct nr_sock *nr = nr_sk(sk);
283 
        int queued = 0, frametype;
284 
 
285 
        if (nr->state == NR_STATE_0)
286 
                return 0;
287 
 
288 
        frametype = skb->data[19];
289 
 
290 
        switch (nr->state) {
291 
        case NR_STATE_1:
292 
                queued = nr_state1_machine(sk, skb, frametype);
293 
                break;
294 
        case NR_STATE_2:
295 
                queued = nr_state2_machine(sk, skb, frametype);
296 
                break;
297 
        case NR_STATE_3:
298 
                queued = nr_state3_machine(sk, skb, frametype);
299 
                break;
300 
        }
301 
 
302 
        nr_kick(sk);
303 
 
304 
        return queued;
305 
}

powered by: WebSVN 2.1.0

© copyright 1999-2025 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.