Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 248 insertions, 0 deletions

diff --git a/net/ax25/ax25_ip.c b/net/ax25/ax25_ip.c
new file mode 100644
index 000000000..e4f63dd43
--- /dev/null
+++ b/net/ax25/ax25_ip.c
@@ -0,0 +1,248 @@
+// 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/module.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/if_arp.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <linux/uaccess.h>
+#include <linux/fcntl.h>
+#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/sysctl.h>
+#include <net/ip.h>
+#include <net/arp.h>
+
+/*
+ *	IP over AX.25 encapsulation.
+ */
+
+/*
+ *	Shove an AX.25 UI header on an IP packet and handle ARP
+ */
+
+#ifdef CONFIG_INET
+
+static int ax25_hard_header(struct sk_buff *skb, struct net_device *dev,
+			    unsigned short type, const void *daddr,
+			    const void *saddr, unsigned int len)
+{
+	unsigned char *buff;
+
+	/* they sometimes come back to us... */
+	if (type == ETH_P_AX25)
+		return 0;
+
+	/* header is an AX.25 UI frame from us to them */
+	buff = skb_push(skb, AX25_HEADER_LEN);
+	*buff++ = 0x00;	/* KISS DATA */
+
+	if (daddr != NULL)
+		memcpy(buff, daddr, dev->addr_len);	/* Address specified */
+
+	buff[6] &= ~AX25_CBIT;
+	buff[6] &= ~AX25_EBIT;
+	buff[6] |= AX25_SSSID_SPARE;
+	buff    += AX25_ADDR_LEN;
+
+	if (saddr != NULL)
+		memcpy(buff, saddr, dev->addr_len);
+	else
+		memcpy(buff, dev->dev_addr, dev->addr_len);
+
+	buff[6] &= ~AX25_CBIT;
+	buff[6] |= AX25_EBIT;
+	buff[6] |= AX25_SSSID_SPARE;
+	buff    += AX25_ADDR_LEN;
+
+	*buff++  = AX25_UI;	/* UI */
+
+	/* Append a suitable AX.25 PID */
+	switch (type) {
+	case ETH_P_IP:
+		*buff++ = AX25_P_IP;
+		break;
+	case ETH_P_ARP:
+		*buff++ = AX25_P_ARP;
+		break;
+	default:
+		printk(KERN_ERR "AX.25: ax25_hard_header - wrong protocol type 0x%2.2x\n", type);
+		*buff++ = 0;
+		break;
+	}
+
+	if (daddr != NULL)
+		return AX25_HEADER_LEN;
+
+	return -AX25_HEADER_LEN;	/* Unfinished header */
+}
+
+netdev_tx_t ax25_ip_xmit(struct sk_buff *skb)
+{
+	struct sk_buff *ourskb;
+	unsigned char *bp  = skb->data;
+	ax25_route *route;
+	struct net_device *dev = NULL;
+	ax25_address *src, *dst;
+	ax25_digi *digipeat = NULL;
+	ax25_dev *ax25_dev;
+	ax25_cb *ax25;
+	char ip_mode = ' ';
+
+	dst = (ax25_address *)(bp + 1);
+	src = (ax25_address *)(bp + 8);
+
+	ax25_route_lock_use();
+	route = ax25_get_route(dst, NULL);
+	if (route) {
+		digipeat = route->digipeat;
+		dev = route->dev;
+		ip_mode = route->ip_mode;
+	}
+
+	if (dev == NULL)
+		dev = skb->dev;
+
+	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) {
+		kfree_skb(skb);
+		goto put;
+	}
+
+	if (bp[16] == AX25_P_IP) {
+		if (ip_mode == 'V' || (ip_mode == ' ' && ax25_dev->values[AX25_VALUES_IPDEFMODE])) {
+			/*
+			 *	We copy the buffer and release the original thereby
+			 *	keeping it straight
+			 *
+			 *	Note: we report 1 back so the caller will
+			 *	not feed the frame direct to the physical device
+			 *	We don't want that to happen. (It won't be upset
+			 *	as we have pulled the frame from the queue by
+			 *	freeing it).
+			 *
+			 *	NB: TCP modifies buffers that are still
+			 *	on a device queue, thus we use skb_copy()
+			 *      instead of using skb_clone() unless this
+			 *	gets fixed.
+			 */
+
+			ax25_address src_c;
+			ax25_address dst_c;
+
+			if ((ourskb = skb_copy(skb, GFP_ATOMIC)) == NULL) {
+				kfree_skb(skb);
+				goto put;
+			}
+
+			if (skb->sk != NULL)
+				skb_set_owner_w(ourskb, skb->sk);
+
+			kfree_skb(skb);
+			/* dl9sau: bugfix
+			 * after kfree_skb(), dst and src which were pointer
+			 * to bp which is part of skb->data would not be valid
+			 * anymore hope that after skb_pull(ourskb, ..) our
+			 * dsc_c and src_c will not become invalid
+			 */
+			bp  = ourskb->data;
+			dst_c = *(ax25_address *)(bp + 1);
+			src_c = *(ax25_address *)(bp + 8);
+
+			skb_pull(ourskb, AX25_HEADER_LEN - 1);	/* Keep PID */
+			skb_reset_network_header(ourskb);
+
+			ax25=ax25_send_frame(
+			    ourskb,
+			    ax25_dev->values[AX25_VALUES_PACLEN],
+			    &src_c,
+			    &dst_c, digipeat, dev);
+			if (ax25) {
+				ax25_cb_put(ax25);
+			}
+			goto put;
+		}
+	}
+
+	bp[7]  &= ~AX25_CBIT;
+	bp[7]  &= ~AX25_EBIT;
+	bp[7]  |= AX25_SSSID_SPARE;
+
+	bp[14] &= ~AX25_CBIT;
+	bp[14] |= AX25_EBIT;
+	bp[14] |= AX25_SSSID_SPARE;
+
+	skb_pull(skb, AX25_KISS_HEADER_LEN);
+
+	if (digipeat != NULL) {
+		if ((ourskb = ax25_rt_build_path(skb, src, dst, route->digipeat)) == NULL) {
+			kfree_skb(skb);
+			goto put;
+		}
+
+		skb = ourskb;
+	}
+
+	ax25_queue_xmit(skb, dev);
+
+put:
+
+	ax25_route_lock_unuse();
+	return NETDEV_TX_OK;
+}
+
+#else	/* INET */
+
+static int ax25_hard_header(struct sk_buff *skb, struct net_device *dev,
+			    unsigned short type, const void *daddr,
+			    const void *saddr, unsigned int len)
+{
+	return -AX25_HEADER_LEN;
+}
+
+netdev_tx_t ax25_ip_xmit(struct sk_buff *skb)
+{
+	kfree_skb(skb);
+	return NETDEV_TX_OK;
+}
+#endif
+
+static bool ax25_validate_header(const char *header, unsigned int len)
+{
+	ax25_digi digi;
+
+	if (!len)
+		return false;
+
+	if (header[0])
+		return true;
+
+	return ax25_addr_parse(header + 1, len - 1, NULL, NULL, &digi, NULL,
+			       NULL);
+}
+
+const struct header_ops ax25_header_ops = {
+	.create = ax25_hard_header,
+	.validate = ax25_validate_header,
+};
+
+EXPORT_SYMBOL(ax25_header_ops);
+EXPORT_SYMBOL(ax25_ip_xmit);