1 files changed, 556 insertions, 0 deletions

diff --git a/net/rose/rose_subr.c b/net/rose/rose_subr.c
new file mode 100644
index 000000000..4dbc437a9
--- /dev/null
+++ b/net/rose/rose_subr.c
@@ -0,0 +1,556 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ */
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/slab.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 <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/rose.h>
+
+static int rose_create_facilities(unsigned char *buffer, struct rose_sock *rose);
+
+/*
+ *	This routine purges all of the queues of frames.
+ */
+void rose_clear_queues(struct sock *sk)
+{
+	skb_queue_purge(&sk->sk_write_queue);
+	skb_queue_purge(&rose_sk(sk)->ack_queue);
+}
+
+/*
+ * This routine purges the input queue of those frames that have been
+ * acknowledged. This replaces the boxes labelled "V(a) <- N(r)" on the
+ * SDL diagram.
+ */
+void rose_frames_acked(struct sock *sk, unsigned short nr)
+{
+	struct sk_buff *skb;
+	struct rose_sock *rose = rose_sk(sk);
+
+	/*
+	 * Remove all the ack-ed frames from the ack queue.
+	 */
+	if (rose->va != nr) {
+		while (skb_peek(&rose->ack_queue) != NULL && rose->va != nr) {
+			skb = skb_dequeue(&rose->ack_queue);
+			kfree_skb(skb);
+			rose->va = (rose->va + 1) % ROSE_MODULUS;
+		}
+	}
+}
+
+void rose_requeue_frames(struct sock *sk)
+{
+	struct sk_buff *skb, *skb_prev = NULL;
+
+	/*
+	 * Requeue all the un-ack-ed frames on the output queue to be picked
+	 * up by rose_kick. This arrangement handles the possibility of an
+	 * empty output queue.
+	 */
+	while ((skb = skb_dequeue(&rose_sk(sk)->ack_queue)) != NULL) {
+		if (skb_prev == NULL)
+			skb_queue_head(&sk->sk_write_queue, skb);
+		else
+			skb_append(skb_prev, skb, &sk->sk_write_queue);
+		skb_prev = skb;
+	}
+}
+
+/*
+ *	Validate that the value of nr is between va and vs. Return true or
+ *	false for testing.
+ */
+int rose_validate_nr(struct sock *sk, unsigned short nr)
+{
+	struct rose_sock *rose = rose_sk(sk);
+	unsigned short vc = rose->va;
+
+	while (vc != rose->vs) {
+		if (nr == vc) return 1;
+		vc = (vc + 1) % ROSE_MODULUS;
+	}
+
+	return nr == rose->vs;
+}
+
+/*
+ *  This routine is called when the packet layer internally generates a
+ *  control frame.
+ */
+void rose_write_internal(struct sock *sk, int frametype)
+{
+	struct rose_sock *rose = rose_sk(sk);
+	struct sk_buff *skb;
+	unsigned char  *dptr;
+	unsigned char  lci1, lci2;
+	int maxfaclen = 0;
+	int len, faclen;
+	int reserve;
+
+	reserve = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + 1;
+	len = ROSE_MIN_LEN;
+
+	switch (frametype) {
+	case ROSE_CALL_REQUEST:
+		len   += 1 + ROSE_ADDR_LEN + ROSE_ADDR_LEN;
+		maxfaclen = 256;
+		break;
+	case ROSE_CALL_ACCEPTED:
+	case ROSE_CLEAR_REQUEST:
+	case ROSE_RESET_REQUEST:
+		len   += 2;
+		break;
+	}
+
+	skb = alloc_skb(reserve + len + maxfaclen, GFP_ATOMIC);
+	if (!skb)
+		return;
+
+	/*
+	 *	Space for AX.25 header and PID.
+	 */
+	skb_reserve(skb, reserve);
+
+	dptr = skb_put(skb, len);
+
+	lci1 = (rose->lci >> 8) & 0x0F;
+	lci2 = (rose->lci >> 0) & 0xFF;
+
+	switch (frametype) {
+	case ROSE_CALL_REQUEST:
+		*dptr++ = ROSE_GFI | lci1;
+		*dptr++ = lci2;
+		*dptr++ = frametype;
+		*dptr++ = ROSE_CALL_REQ_ADDR_LEN_VAL;
+		memcpy(dptr, &rose->dest_addr,  ROSE_ADDR_LEN);
+		dptr   += ROSE_ADDR_LEN;
+		memcpy(dptr, &rose->source_addr, ROSE_ADDR_LEN);
+		dptr   += ROSE_ADDR_LEN;
+		faclen = rose_create_facilities(dptr, rose);
+		skb_put(skb, faclen);
+		dptr   += faclen;
+		break;
+
+	case ROSE_CALL_ACCEPTED:
+		*dptr++ = ROSE_GFI | lci1;
+		*dptr++ = lci2;
+		*dptr++ = frametype;
+		*dptr++ = 0x00;		/* Address length */
+		*dptr++ = 0;		/* Facilities length */
+		break;
+
+	case ROSE_CLEAR_REQUEST:
+		*dptr++ = ROSE_GFI | lci1;
+		*dptr++ = lci2;
+		*dptr++ = frametype;
+		*dptr++ = rose->cause;
+		*dptr++ = rose->diagnostic;
+		break;
+
+	case ROSE_RESET_REQUEST:
+		*dptr++ = ROSE_GFI | lci1;
+		*dptr++ = lci2;
+		*dptr++ = frametype;
+		*dptr++ = ROSE_DTE_ORIGINATED;
+		*dptr++ = 0;
+		break;
+
+	case ROSE_RR:
+	case ROSE_RNR:
+		*dptr++ = ROSE_GFI | lci1;
+		*dptr++ = lci2;
+		*dptr   = frametype;
+		*dptr++ |= (rose->vr << 5) & 0xE0;
+		break;
+
+	case ROSE_CLEAR_CONFIRMATION:
+	case ROSE_RESET_CONFIRMATION:
+		*dptr++ = ROSE_GFI | lci1;
+		*dptr++ = lci2;
+		*dptr++  = frametype;
+		break;
+
+	default:
+		printk(KERN_ERR "ROSE: rose_write_internal - invalid frametype %02X\n", frametype);
+		kfree_skb(skb);
+		return;
+	}
+
+	rose_transmit_link(skb, rose->neighbour);
+}
+
+int rose_decode(struct sk_buff *skb, int *ns, int *nr, int *q, int *d, int *m)
+{
+	unsigned char *frame;
+
+	frame = skb->data;
+
+	*ns = *nr = *q = *d = *m = 0;
+
+	switch (frame[2]) {
+	case ROSE_CALL_REQUEST:
+	case ROSE_CALL_ACCEPTED:
+	case ROSE_CLEAR_REQUEST:
+	case ROSE_CLEAR_CONFIRMATION:
+	case ROSE_RESET_REQUEST:
+	case ROSE_RESET_CONFIRMATION:
+		return frame[2];
+	default:
+		break;
+	}
+
+	if ((frame[2] & 0x1F) == ROSE_RR  ||
+	    (frame[2] & 0x1F) == ROSE_RNR) {
+		*nr = (frame[2] >> 5) & 0x07;
+		return frame[2] & 0x1F;
+	}
+
+	if ((frame[2] & 0x01) == ROSE_DATA) {
+		*q  = (frame[0] & ROSE_Q_BIT) == ROSE_Q_BIT;
+		*d  = (frame[0] & ROSE_D_BIT) == ROSE_D_BIT;
+		*m  = (frame[2] & ROSE_M_BIT) == ROSE_M_BIT;
+		*nr = (frame[2] >> 5) & 0x07;
+		*ns = (frame[2] >> 1) & 0x07;
+		return ROSE_DATA;
+	}
+
+	return ROSE_ILLEGAL;
+}
+
+static int rose_parse_national(unsigned char *p, struct rose_facilities_struct *facilities, int len)
+{
+	unsigned char *pt;
+	unsigned char l, lg, n = 0;
+	int fac_national_digis_received = 0;
+
+	do {
+		switch (*p & 0xC0) {
+		case 0x00:
+			if (len < 2)
+				return -1;
+			p   += 2;
+			n   += 2;
+			len -= 2;
+			break;
+
+		case 0x40:
+			if (len < 3)
+				return -1;
+			if (*p == FAC_NATIONAL_RAND)
+				facilities->rand = ((p[1] << 8) & 0xFF00) + ((p[2] << 0) & 0x00FF);
+			p   += 3;
+			n   += 3;
+			len -= 3;
+			break;
+
+		case 0x80:
+			if (len < 4)
+				return -1;
+			p   += 4;
+			n   += 4;
+			len -= 4;
+			break;
+
+		case 0xC0:
+			if (len < 2)
+				return -1;
+			l = p[1];
+			if (len < 2 + l)
+				return -1;
+			if (*p == FAC_NATIONAL_DEST_DIGI) {
+				if (!fac_national_digis_received) {
+					if (l < AX25_ADDR_LEN)
+						return -1;
+					memcpy(&facilities->source_digis[0], p + 2, AX25_ADDR_LEN);
+					facilities->source_ndigis = 1;
+				}
+			}
+			else if (*p == FAC_NATIONAL_SRC_DIGI) {
+				if (!fac_national_digis_received) {
+					if (l < AX25_ADDR_LEN)
+						return -1;
+					memcpy(&facilities->dest_digis[0], p + 2, AX25_ADDR_LEN);
+					facilities->dest_ndigis = 1;
+				}
+			}
+			else if (*p == FAC_NATIONAL_FAIL_CALL) {
+				if (l < AX25_ADDR_LEN)
+					return -1;
+				memcpy(&facilities->fail_call, p + 2, AX25_ADDR_LEN);
+			}
+			else if (*p == FAC_NATIONAL_FAIL_ADD) {
+				if (l < 1 + ROSE_ADDR_LEN)
+					return -1;
+				memcpy(&facilities->fail_addr, p + 3, ROSE_ADDR_LEN);
+			}
+			else if (*p == FAC_NATIONAL_DIGIS) {
+				if (l % AX25_ADDR_LEN)
+					return -1;
+				fac_national_digis_received = 1;
+				facilities->source_ndigis = 0;
+				facilities->dest_ndigis   = 0;
+				for (pt = p + 2, lg = 0 ; lg < l ; pt += AX25_ADDR_LEN, lg += AX25_ADDR_LEN) {
+					if (pt[6] & AX25_HBIT) {
+						if (facilities->dest_ndigis >= ROSE_MAX_DIGIS)
+							return -1;
+						memcpy(&facilities->dest_digis[facilities->dest_ndigis++], pt, AX25_ADDR_LEN);
+					} else {
+						if (facilities->source_ndigis >= ROSE_MAX_DIGIS)
+							return -1;
+						memcpy(&facilities->source_digis[facilities->source_ndigis++], pt, AX25_ADDR_LEN);
+					}
+				}
+			}
+			p   += l + 2;
+			n   += l + 2;
+			len -= l + 2;
+			break;
+		}
+	} while (*p != 0x00 && len > 0);
+
+	return n;
+}
+
+static int rose_parse_ccitt(unsigned char *p, struct rose_facilities_struct *facilities, int len)
+{
+	unsigned char l, n = 0;
+	char callsign[11];
+
+	do {
+		switch (*p & 0xC0) {
+		case 0x00:
+			if (len < 2)
+				return -1;
+			p   += 2;
+			n   += 2;
+			len -= 2;
+			break;
+
+		case 0x40:
+			if (len < 3)
+				return -1;
+			p   += 3;
+			n   += 3;
+			len -= 3;
+			break;
+
+		case 0x80:
+			if (len < 4)
+				return -1;
+			p   += 4;
+			n   += 4;
+			len -= 4;
+			break;
+
+		case 0xC0:
+			if (len < 2)
+				return -1;
+			l = p[1];
+
+			/* Prevent overflows*/
+			if (l < 10 || l > 20)
+				return -1;
+
+			if (*p == FAC_CCITT_DEST_NSAP) {
+				memcpy(&facilities->source_addr, p + 7, ROSE_ADDR_LEN);
+				memcpy(callsign, p + 12,   l - 10);
+				callsign[l - 10] = '\0';
+				asc2ax(&facilities->source_call, callsign);
+			}
+			if (*p == FAC_CCITT_SRC_NSAP) {
+				memcpy(&facilities->dest_addr, p + 7, ROSE_ADDR_LEN);
+				memcpy(callsign, p + 12, l - 10);
+				callsign[l - 10] = '\0';
+				asc2ax(&facilities->dest_call, callsign);
+			}
+			p   += l + 2;
+			n   += l + 2;
+			len -= l + 2;
+			break;
+		}
+	} while (*p != 0x00 && len > 0);
+
+	return n;
+}
+
+int rose_parse_facilities(unsigned char *p, unsigned packet_len,
+	struct rose_facilities_struct *facilities)
+{
+	int facilities_len, len;
+
+	facilities_len = *p++;
+
+	if (facilities_len == 0 || (unsigned int)facilities_len > packet_len)
+		return 0;
+
+	while (facilities_len >= 3 && *p == 0x00) {
+		facilities_len--;
+		p++;
+
+		switch (*p) {
+		case FAC_NATIONAL:		/* National */
+			len = rose_parse_national(p + 1, facilities, facilities_len - 1);
+			break;
+
+		case FAC_CCITT:		/* CCITT */
+			len = rose_parse_ccitt(p + 1, facilities, facilities_len - 1);
+			break;
+
+		default:
+			printk(KERN_DEBUG "ROSE: rose_parse_facilities - unknown facilities family %02X\n", *p);
+			len = 1;
+			break;
+		}
+
+		if (len < 0)
+			return 0;
+		if (WARN_ON(len >= facilities_len))
+			return 0;
+		facilities_len -= len + 1;
+		p += len + 1;
+	}
+
+	return facilities_len == 0;
+}
+
+static int rose_create_facilities(unsigned char *buffer, struct rose_sock *rose)
+{
+	unsigned char *p = buffer + 1;
+	char *callsign;
+	char buf[11];
+	int len, nb;
+
+	/* National Facilities */
+	if (rose->rand != 0 || rose->source_ndigis == 1 || rose->dest_ndigis == 1) {
+		*p++ = 0x00;
+		*p++ = FAC_NATIONAL;
+
+		if (rose->rand != 0) {
+			*p++ = FAC_NATIONAL_RAND;
+			*p++ = (rose->rand >> 8) & 0xFF;
+			*p++ = (rose->rand >> 0) & 0xFF;
+		}
+
+		/* Sent before older facilities */
+		if ((rose->source_ndigis > 0) || (rose->dest_ndigis > 0)) {
+			int maxdigi = 0;
+			*p++ = FAC_NATIONAL_DIGIS;
+			*p++ = AX25_ADDR_LEN * (rose->source_ndigis + rose->dest_ndigis);
+			for (nb = 0 ; nb < rose->source_ndigis ; nb++) {
+				if (++maxdigi >= ROSE_MAX_DIGIS)
+					break;
+				memcpy(p, &rose->source_digis[nb], AX25_ADDR_LEN);
+				p[6] |= AX25_HBIT;
+				p += AX25_ADDR_LEN;
+			}
+			for (nb = 0 ; nb < rose->dest_ndigis ; nb++) {
+				if (++maxdigi >= ROSE_MAX_DIGIS)
+					break;
+				memcpy(p, &rose->dest_digis[nb], AX25_ADDR_LEN);
+				p[6] &= ~AX25_HBIT;
+				p += AX25_ADDR_LEN;
+			}
+		}
+
+		/* For compatibility */
+		if (rose->source_ndigis > 0) {
+			*p++ = FAC_NATIONAL_SRC_DIGI;
+			*p++ = AX25_ADDR_LEN;
+			memcpy(p, &rose->source_digis[0], AX25_ADDR_LEN);
+			p   += AX25_ADDR_LEN;
+		}
+
+		/* For compatibility */
+		if (rose->dest_ndigis > 0) {
+			*p++ = FAC_NATIONAL_DEST_DIGI;
+			*p++ = AX25_ADDR_LEN;
+			memcpy(p, &rose->dest_digis[0], AX25_ADDR_LEN);
+			p   += AX25_ADDR_LEN;
+		}
+	}
+
+	*p++ = 0x00;
+	*p++ = FAC_CCITT;
+
+	*p++ = FAC_CCITT_DEST_NSAP;
+
+	callsign = ax2asc(buf, &rose->dest_call);
+
+	*p++ = strlen(callsign) + 10;
+	*p++ = (strlen(callsign) + 9) * 2;		/* ??? */
+
+	*p++ = 0x47; *p++ = 0x00; *p++ = 0x11;
+	*p++ = ROSE_ADDR_LEN * 2;
+	memcpy(p, &rose->dest_addr, ROSE_ADDR_LEN);
+	p   += ROSE_ADDR_LEN;
+
+	memcpy(p, callsign, strlen(callsign));
+	p   += strlen(callsign);
+
+	*p++ = FAC_CCITT_SRC_NSAP;
+
+	callsign = ax2asc(buf, &rose->source_call);
+
+	*p++ = strlen(callsign) + 10;
+	*p++ = (strlen(callsign) + 9) * 2;		/* ??? */
+
+	*p++ = 0x47; *p++ = 0x00; *p++ = 0x11;
+	*p++ = ROSE_ADDR_LEN * 2;
+	memcpy(p, &rose->source_addr, ROSE_ADDR_LEN);
+	p   += ROSE_ADDR_LEN;
+
+	memcpy(p, callsign, strlen(callsign));
+	p   += strlen(callsign);
+
+	len       = p - buffer;
+	buffer[0] = len - 1;
+
+	return len;
+}
+
+void rose_disconnect(struct sock *sk, int reason, int cause, int diagnostic)
+{
+	struct rose_sock *rose = rose_sk(sk);
+
+	rose_stop_timer(sk);
+	rose_stop_idletimer(sk);
+
+	rose_clear_queues(sk);
+
+	rose->lci   = 0;
+	rose->state = ROSE_STATE_0;
+
+	if (cause != -1)
+		rose->cause = cause;
+
+	if (diagnostic != -1)
+		rose->diagnostic = diagnostic;
+
+	sk->sk_state     = TCP_CLOSE;
+	sk->sk_err       = reason;
+	sk->sk_shutdown |= SEND_SHUTDOWN;
+
+	if (!sock_flag(sk, SOCK_DEAD)) {
+		sk->sk_state_change(sk);
+		sock_set_flag(sk, SOCK_DEAD);
+	}
+}