[linux.git] / net / netrom / nr_in.c

/*
 * 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 Jonathan Naylor G4KLX ([email protected])
 * Copyright Darryl Miles G7LED ([email protected])
 */
#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/tcp_states.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <net/netrom.h>

static int nr_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more)
{
	struct sk_buff *skbo, *skbn = skb;
	struct nr_sock *nr = nr_sk(sk);

	skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);

	nr_start_idletimer(sk);

	if (more) {
		nr->fraglen += skb->len;
		skb_queue_tail(&nr->frag_queue, skb);
		return 0;
	}

	if (!more && nr->fraglen > 0) {	/* End of fragment */
		nr->fraglen += skb->len;
		skb_queue_tail(&nr->frag_queue, skb);

		if ((skbn = alloc_skb(nr->fraglen, GFP_ATOMIC)) == NULL)
			return 1;

		skbn->h.raw = skbn->data;

		while ((skbo = skb_dequeue(&nr->frag_queue)) != NULL) {
			memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);
			kfree_skb(skbo);
		}

		nr->fraglen = 0;
	}

	return sock_queue_rcv_skb(sk, skbn);
}

/*
 * State machine for state 1, Awaiting Connection State.
 * The handling of the timer(s) is in file nr_timer.c.
 * Handling of state 0 and connection release is in netrom.c.
 */
static int nr_state1_machine(struct sock *sk, struct sk_buff *skb,
	int frametype)
{
	switch (frametype) {
	case NR_CONNACK: {
		struct nr_sock *nr = nr_sk(sk);

		nr_stop_t1timer(sk);
		nr_start_idletimer(sk);
		nr->your_index = skb->data[17];
		nr->your_id    = skb->data[18];
		nr->vs	       = 0;
		nr->va	       = 0;
		nr->vr	       = 0;
		nr->vl	       = 0;
		nr->state      = NR_STATE_3;
		nr->n2count    = 0;
		nr->window     = skb->data[20];
		sk->sk_state   = TCP_ESTABLISHED;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_state_change(sk);
		break;
	}

	case NR_CONNACK | NR_CHOKE_FLAG:
		nr_disconnect(sk, ECONNREFUSED);
		break;

	case NR_RESET:
		if (sysctl_netrom_reset_circuit)
			nr_disconnect(sk, ECONNRESET);
		break;

	default:
		break;
	}
	return 0;
}

/*
 * State machine for state 2, Awaiting Release State.
 * The handling of the timer(s) is in file nr_timer.c
 * Handling of state 0 and connection release is in netrom.c.
 */
static int nr_state2_machine(struct sock *sk, struct sk_buff *skb,
	int frametype)
{
	switch (frametype) {
	case NR_CONNACK | NR_CHOKE_FLAG:
		nr_disconnect(sk, ECONNRESET);
		break;

	case NR_DISCREQ:
		nr_write_internal(sk, NR_DISCACK);

	case NR_DISCACK:
		nr_disconnect(sk, 0);
		break;

	case NR_RESET:
		if (sysctl_netrom_reset_circuit)
			nr_disconnect(sk, ECONNRESET);
		break;

	default:
		break;
	}
	return 0;
}

/*
 * State machine for state 3, Connected State.
 * The handling of the timer(s) is in file nr_timer.c
 * Handling of state 0 and connection release is in netrom.c.
 */
static int nr_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype)
{
	struct nr_sock *nrom = nr_sk(sk);
	struct sk_buff_head temp_queue;
	struct sk_buff *skbn;
	unsigned short save_vr;
	unsigned short nr, ns;
	int queued = 0;

	nr = skb->data[18];
	ns = skb->data[17];

	switch (frametype) {
	case NR_CONNREQ:
		nr_write_internal(sk, NR_CONNACK);
		break;

	case NR_DISCREQ:
		nr_write_internal(sk, NR_DISCACK);
		nr_disconnect(sk, 0);
		break;

	case NR_CONNACK | NR_CHOKE_FLAG:
	case NR_DISCACK:
		nr_disconnect(sk, ECONNRESET);
		break;

	case NR_INFOACK:
	case NR_INFOACK | NR_CHOKE_FLAG:
	case NR_INFOACK | NR_NAK_FLAG:
	case NR_INFOACK | NR_NAK_FLAG | NR_CHOKE_FLAG:
		if (frametype & NR_CHOKE_FLAG) {
			nrom->condition |= NR_COND_PEER_RX_BUSY;
			nr_start_t4timer(sk);
		} else {
			nrom->condition &= ~NR_COND_PEER_RX_BUSY;
			nr_stop_t4timer(sk);
		}
		if (!nr_validate_nr(sk, nr)) {
			break;
		}
		if (frametype & NR_NAK_FLAG) {
			nr_frames_acked(sk, nr);
			nr_send_nak_frame(sk);
		} else {
			if (nrom->condition & NR_COND_PEER_RX_BUSY) {
				nr_frames_acked(sk, nr);
			} else {
				nr_check_iframes_acked(sk, nr);
			}
		}
		break;

	case NR_INFO:
	case NR_INFO | NR_NAK_FLAG:
	case NR_INFO | NR_CHOKE_FLAG:
	case NR_INFO | NR_MORE_FLAG:
	case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG:
	case NR_INFO | NR_CHOKE_FLAG | NR_MORE_FLAG:
	case NR_INFO | NR_NAK_FLAG | NR_MORE_FLAG:
	case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG | NR_MORE_FLAG:
		if (frametype & NR_CHOKE_FLAG) {
			nrom->condition |= NR_COND_PEER_RX_BUSY;
			nr_start_t4timer(sk);
		} else {
			nrom->condition &= ~NR_COND_PEER_RX_BUSY;
			nr_stop_t4timer(sk);
		}
		if (nr_validate_nr(sk, nr)) {
			if (frametype & NR_NAK_FLAG) {
				nr_frames_acked(sk, nr);
				nr_send_nak_frame(sk);
			} else {
				if (nrom->condition & NR_COND_PEER_RX_BUSY) {
					nr_frames_acked(sk, nr);
				} else {
					nr_check_iframes_acked(sk, nr);
				}
			}
		}
		queued = 1;
		skb_queue_head(&nrom->reseq_queue, skb);
		if (nrom->condition & NR_COND_OWN_RX_BUSY)
			break;
		skb_queue_head_init(&temp_queue);
		do {
			save_vr = nrom->vr;
			while ((skbn = skb_dequeue(&nrom->reseq_queue)) != NULL) {
				ns = skbn->data[17];
				if (ns == nrom->vr) {
					if (nr_queue_rx_frame(sk, skbn, frametype & NR_MORE_FLAG) == 0) {
						nrom->vr = (nrom->vr + 1) % NR_MODULUS;
					} else {
						nrom->condition |= NR_COND_OWN_RX_BUSY;
						skb_queue_tail(&temp_queue, skbn);
					}
				} else if (nr_in_rx_window(sk, ns)) {
					skb_queue_tail(&temp_queue, skbn);
				} else {
					kfree_skb(skbn);
				}
			}
			while ((skbn = skb_dequeue(&temp_queue)) != NULL) {
				skb_queue_tail(&nrom->reseq_queue, skbn);
			}
		} while (save_vr != nrom->vr);
		/*
		 * Window is full, ack it immediately.
		 */
		if (((nrom->vl + nrom->window) % NR_MODULUS) == nrom->vr) {
			nr_enquiry_response(sk);
		} else {
			if (!(nrom->condition & NR_COND_ACK_PENDING)) {
				nrom->condition |= NR_COND_ACK_PENDING;
				nr_start_t2timer(sk);
			}
		}
		break;

	case NR_RESET:
		if (sysctl_netrom_reset_circuit)
			nr_disconnect(sk, ECONNRESET);
		break;

	default:
		break;
	}
	return queued;
}

/* Higher level upcall for a LAPB frame - called with sk locked */
int nr_process_rx_frame(struct sock *sk, struct sk_buff *skb)
{
	struct nr_sock *nr = nr_sk(sk);
	int queued = 0, frametype;

	if (nr->state == NR_STATE_0)
		return 0;

	frametype = skb->data[19];

	switch (nr->state) {
	case NR_STATE_1:
		queued = nr_state1_machine(sk, skb, frametype);
		break;
	case NR_STATE_2:
		queued = nr_state2_machine(sk, skb, frametype);
		break;
	case NR_STATE_3:
		queued = nr_state3_machine(sk, skb, frametype);
		break;
	}

	nr_kick(sk);

	return queued;
}
Commit	Line	Data
1da177e4 LT	1	/*
	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 ([email protected])
	8	* Copyright Darryl Miles G7LED ([email protected])
	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/sched.h>
	16	#include <linux/timer.h>
	17	#include <linux/string.h>
	18	#include <linux/sockios.h>
	19	#include <linux/net.h>
	20	#include <net/ax25.h>
	21	#include <linux/inet.h>
	22	#include <linux/netdevice.h>
	23	#include <linux/skbuff.h>
	24	#include <net/sock.h>
c752f073	25	#include <net/tcp_states.h>
1da177e4 LT	26	#include <asm/uaccess.h>
	27	#include <asm/system.h>
	28	#include <linux/fcntl.h>
	29	#include <linux/mm.h>
	30	#include <linux/interrupt.h>
	31	#include <net/netrom.h>
	32
	33	static int nr_queue_rx_frame(struct sock sk, struct sk_buff skb, int more)
	34	{
	35	struct sk_buff skbo, skbn = skb;
	36	struct nr_sock *nr = nr_sk(sk);
	37
	38	skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
	39
	40	nr_start_idletimer(sk);
	41
	42	if (more) {
	43	nr->fraglen += skb->len;
	44	skb_queue_tail(&nr->frag_queue, skb);
	45	return 0;
	46	}
	47
	48	if (!more && nr->fraglen > 0) { /* End of fragment */
	49	nr->fraglen += skb->len;
	50	skb_queue_tail(&nr->frag_queue, skb);
	51
	52	if ((skbn = alloc_skb(nr->fraglen, GFP_ATOMIC)) == NULL)
	53	return 1;
	54
	55	skbn->h.raw = skbn->data;
	56
	57	while ((skbo = skb_dequeue(&nr->frag_queue)) != NULL) {
	58	memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);
	59	kfree_skb(skbo);
	60	}
	61
	62	nr->fraglen = 0;
	63	}
	64
	65	return sock_queue_rcv_skb(sk, skbn);
	66	}
	67
	68	/*
	69	* State machine for state 1, Awaiting Connection State.
	70	* The handling of the timer(s) is in file nr_timer.c.
	71	* Handling of state 0 and connection release is in netrom.c.
	72	*/
	73	static int nr_state1_machine(struct sock sk, struct sk_buff skb,
	74	int frametype)
	75	{
	76	switch (frametype) {
	77	case NR_CONNACK: {
	78	struct nr_sock *nr = nr_sk(sk);
	79
	80	nr_stop_t1timer(sk);
	81	nr_start_idletimer(sk);
	82	nr->your_index = skb->data[17];
	83	nr->your_id = skb->data[18];
	84	nr->vs = 0;
	85	nr->va = 0;
	86	nr->vr = 0;
	87	nr->vl = 0;
	88	nr->state = NR_STATE_3;
	89	nr->n2count = 0;
90	nr->window = skb->data[20];
91	sk->sk_state = TCP_ESTABLISHED;
92	if (!sock_flag(sk, SOCK_DEAD))
93	sk->sk_state_change(sk);
94	break;
95	}
96
97	case NR_CONNACK \| NR_CHOKE_FLAG:
98	nr_disconnect(sk, ECONNREFUSED);
99	break;
100
e21ce8c7	101	case NR_RESET:
0d77d59f	102	if (sysctl_netrom_reset_circuit)
e21ce8c7 RB	103	nr_disconnect(sk, ECONNRESET);
	104	break;
	105
1da177e4 LT	106	default:
	107	break;
	108	}
	109	return 0;
	110	}
	111
	112	/*
	113	* State machine for state 2, Awaiting Release State.
	114	* The handling of the timer(s) is in file nr_timer.c
	115	* Handling of state 0 and connection release is in netrom.c.
	116	*/
	117	static int nr_state2_machine(struct sock sk, struct sk_buff skb,
	118	int frametype)
	119	{
	120	switch (frametype) {
	121	case NR_CONNACK \| NR_CHOKE_FLAG:
	122	nr_disconnect(sk, ECONNRESET);
	123	break;
	124
	125	case NR_DISCREQ:
	126	nr_write_internal(sk, NR_DISCACK);
	127
	128	case NR_DISCACK:
	129	nr_disconnect(sk, 0);
	130	break;
	131
e21ce8c7	132	case NR_RESET:
0d77d59f	133	if (sysctl_netrom_reset_circuit)
e21ce8c7 RB	134	nr_disconnect(sk, ECONNRESET);
	135	break;
	136
1da177e4 LT	137	default:
	138	break;
	139	}
	140	return 0;
	141	}
	142
	143	/*
	144	* State machine for state 3, Connected State.
	145	* The handling of the timer(s) is in file nr_timer.c
	146	* Handling of state 0 and connection release is in netrom.c.
	147	*/
	148	static int nr_state3_machine(struct sock sk, struct sk_buff skb, int frametype)
	149	{
	150	struct nr_sock *nrom = nr_sk(sk);
	151	struct sk_buff_head temp_queue;
	152	struct sk_buff *skbn;
	153	unsigned short save_vr;
	154	unsigned short nr, ns;
	155	int queued = 0;
	156
	157	nr = skb->data[18];
	158	ns = skb->data[17];
	159
	160	switch (frametype) {
	161	case NR_CONNREQ:
	162	nr_write_internal(sk, NR_CONNACK);
	163	break;
	164
	165	case NR_DISCREQ:
	166	nr_write_internal(sk, NR_DISCACK);
	167	nr_disconnect(sk, 0);
	168	break;
	169
	170	case NR_CONNACK \| NR_CHOKE_FLAG:
	171	case NR_DISCACK:
	172	nr_disconnect(sk, ECONNRESET);
	173	break;
	174
	175	case NR_INFOACK:
	176	case NR_INFOACK \| NR_CHOKE_FLAG:
	177	case NR_INFOACK \| NR_NAK_FLAG:
	178	case NR_INFOACK \| NR_NAK_FLAG \| NR_CHOKE_FLAG:
	179	if (frametype & NR_CHOKE_FLAG) {
	180	nrom->condition \|= NR_COND_PEER_RX_BUSY;
	181	nr_start_t4timer(sk);
	182	} else {
	183	nrom->condition &= ~NR_COND_PEER_RX_BUSY;
	184	nr_stop_t4timer(sk);
	185	}
	186	if (!nr_validate_nr(sk, nr)) {
	187	break;
	188	}
	189	if (frametype & NR_NAK_FLAG) {
	190	nr_frames_acked(sk, nr);
	191	nr_send_nak_frame(sk);
	192	} else {
	193	if (nrom->condition & NR_COND_PEER_RX_BUSY) {
	194	nr_frames_acked(sk, nr);
	195	} else {
	196	nr_check_iframes_acked(sk, nr);
	197	}
	198	}
	199	break;
	200
201	case NR_INFO:
202	case NR_INFO \| NR_NAK_FLAG:
203	case NR_INFO \| NR_CHOKE_FLAG:
204	case NR_INFO \| NR_MORE_FLAG:
205	case NR_INFO \| NR_NAK_FLAG \| NR_CHOKE_FLAG:
206	case NR_INFO \| NR_CHOKE_FLAG \| NR_MORE_FLAG:
207	case NR_INFO \| NR_NAK_FLAG \| NR_MORE_FLAG:
208	case NR_INFO \| NR_NAK_FLAG \| NR_CHOKE_FLAG \| NR_MORE_FLAG:
209	if (frametype & NR_CHOKE_FLAG) {
210	nrom->condition \|= NR_COND_PEER_RX_BUSY;
211	nr_start_t4timer(sk);
212	} else {
213	nrom->condition &= ~NR_COND_PEER_RX_BUSY;
214	nr_stop_t4timer(sk);
215	}
216	if (nr_validate_nr(sk, nr)) {
217	if (frametype & NR_NAK_FLAG) {
218	nr_frames_acked(sk, nr);
219	nr_send_nak_frame(sk);
220	} else {
221	if (nrom->condition & NR_COND_PEER_RX_BUSY) {
222	nr_frames_acked(sk, nr);
223	} else {
224	nr_check_iframes_acked(sk, nr);
225	}
226	}
227	}
228	queued = 1;
229	skb_queue_head(&nrom->reseq_queue, skb);
230	if (nrom->condition & NR_COND_OWN_RX_BUSY)
231	break;
232	skb_queue_head_init(&temp_queue);
233	do {
234	save_vr = nrom->vr;
235	while ((skbn = skb_dequeue(&nrom->reseq_queue)) != NULL) {
236	ns = skbn->data[17];
237	if (ns == nrom->vr) {
238	if (nr_queue_rx_frame(sk, skbn, frametype & NR_MORE_FLAG) == 0) {
239	nrom->vr = (nrom->vr + 1) % NR_MODULUS;
240	} else {
241	nrom->condition \|= NR_COND_OWN_RX_BUSY;
242	skb_queue_tail(&temp_queue, skbn);
243	}
244	} else if (nr_in_rx_window(sk, ns)) {
245	skb_queue_tail(&temp_queue, skbn);
246	} else {
247	kfree_skb(skbn);
248	}
249	}
250	while ((skbn = skb_dequeue(&temp_queue)) != NULL) {
251	skb_queue_tail(&nrom->reseq_queue, skbn);
252	}
253	} while (save_vr != nrom->vr);
254	/*
255	* Window is full, ack it immediately.
256	*/
257	if (((nrom->vl + nrom->window) % NR_MODULUS) == nrom->vr) {
258	nr_enquiry_response(sk);
259	} else {
260	if (!(nrom->condition & NR_COND_ACK_PENDING)) {
261	nrom->condition \|= NR_COND_ACK_PENDING;
262	nr_start_t2timer(sk);
263	}
264	}
265	break;
266
e21ce8c7	267	case NR_RESET:
0d77d59f	268	if (sysctl_netrom_reset_circuit)
e21ce8c7 RB	269	nr_disconnect(sk, ECONNRESET);
	270	break;
	271
1da177e4 LT	272	default:
	273	break;
	274	}
	275	return queued;
	276	}
	277
	278	/* Higher level upcall for a LAPB frame - called with sk locked */
	279	int nr_process_rx_frame(struct sock sk, struct sk_buff skb)
	280	{
	281	struct nr_sock *nr = nr_sk(sk);
	282	int queued = 0, frametype;
	283
	284	if (nr->state == NR_STATE_0)
	285	return 0;
	286
	287	frametype = skb->data[19];
	288
	289	switch (nr->state) {
	290	case NR_STATE_1:
	291	queued = nr_state1_machine(sk, skb, frametype);
	292	break;
	293	case NR_STATE_2:
	294	queued = nr_state2_machine(sk, skb, frametype);
	295	break;
	296	case NR_STATE_3:
	297	queued = nr_state3_machine(sk, skb, frametype);
	298	break;
	299	}
	300
	301	nr_kick(sk);
	302
	303	return queued;
	304	}