4 * This code REQUIRES 2.1.15 or higher/ NET3.038
7 * This module is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
13 * AX.25 036 Jonathan(G4KLX) Split from af_ax25.c.
16 #include <linux/config.h>
17 #include <linux/errno.h>
18 #include <linux/types.h>
19 #include <linux/socket.h>
21 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/timer.h>
24 #include <linux/string.h>
25 #include <linux/sockios.h>
26 #include <linux/net.h>
28 #include <linux/inet.h>
29 #include <linux/netdevice.h>
30 #include <linux/if_arp.h>
31 #include <linux/skbuff.h>
33 #include <asm/uaccess.h>
34 #include <asm/system.h>
35 #include <linux/fcntl.h>
36 #include <linux/termios.h> /* For TIOCINQ/OUTQ */
38 #include <linux/interrupt.h>
39 #include <linux/notifier.h>
40 #include <linux/proc_fs.h>
41 #include <linux/stat.h>
42 #include <linux/netfilter.h>
43 #include <linux/sysctl.h>
48 * IP over AX.25 encapsulation.
52 * Shove an AX.25 UI header on an IP packet and handle ARP
57 int ax25_encapsulate(struct sk_buff *skb, struct net_device *dev, unsigned short type, void *daddr, void *saddr, unsigned len)
61 /* they sometimes come back to us... */
62 if (type == ETH_P_AX25)
65 /* header is an AX.25 UI frame from us to them */
66 buff = skb_push(skb, AX25_HEADER_LEN);
67 *buff++ = 0x00; /* KISS DATA */
70 memcpy(buff, daddr, dev->addr_len); /* Address specified */
72 buff[6] &= ~AX25_CBIT;
73 buff[6] &= ~AX25_EBIT;
74 buff[6] |= AX25_SSSID_SPARE;
75 buff += AX25_ADDR_LEN;
78 memcpy(buff, saddr, dev->addr_len);
80 memcpy(buff, dev->dev_addr, dev->addr_len);
82 buff[6] &= ~AX25_CBIT;
84 buff[6] |= AX25_SSSID_SPARE;
85 buff += AX25_ADDR_LEN;
87 *buff++ = AX25_UI; /* UI */
89 /* Append a suitable AX.25 PID */
98 printk(KERN_ERR "AX.25: ax25_encapsulate - wrong protocol type 0x%2.2x\n", type);
104 return AX25_HEADER_LEN;
106 return -AX25_HEADER_LEN; /* Unfinished header */
109 int ax25_rebuild_header(struct sk_buff *skb)
111 struct sk_buff *ourskb;
112 unsigned char *bp = skb->data;
113 struct net_device *dev;
114 ax25_address *src, *dst;
118 dst = (ax25_address *)(bp + 1);
119 src = (ax25_address *)(bp + 8);
121 if (arp_find(bp + 1, skb))
124 route = ax25_rt_find_route(dst, NULL);
130 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
133 if (bp[16] == AX25_P_IP) {
134 if (route->ip_mode == 'V' || (route->ip_mode == ' ' && ax25_dev->values[AX25_VALUES_IPDEFMODE])) {
136 * We copy the buffer and release the original thereby
137 * keeping it straight
139 * Note: we report 1 back so the caller will
140 * not feed the frame direct to the physical device
141 * We don't want that to happen. (It won't be upset
142 * as we have pulled the frame from the queue by
145 * NB: TCP modifies buffers that are still
146 * on a device queue, thus we use skb_copy()
147 * instead of using skb_clone() unless this
154 if ((ourskb = skb_copy(skb, GFP_ATOMIC)) == NULL) {
160 skb_set_owner_w(ourskb, skb->sk);
164 * after kfree_skb(), dst and src which were pointer
165 * to bp which is part of skb->data would not be valid
166 * anymore hope that after skb_pull(ourskb, ..) our
167 * dsc_c and src_c will not become invalid
170 dst_c = *(ax25_address *)(bp + 1);
171 src_c = *(ax25_address *)(bp + 8);
173 skb_pull(ourskb, AX25_HEADER_LEN - 1); /* Keep PID */
174 ourskb->nh.raw = ourskb->data;
176 ax25_send_frame(ourskb, ax25_dev->values[AX25_VALUES_PACLEN], &src_c,
177 &dst_c, route->digipeat, dev);
185 bp[7] |= AX25_SSSID_SPARE;
187 bp[14] &= ~AX25_CBIT;
189 bp[14] |= AX25_SSSID_SPARE;
191 skb_pull(skb, AX25_KISS_HEADER_LEN);
193 if (route->digipeat != NULL) {
194 if ((ourskb = ax25_rt_build_path(skb, src, dst, route->digipeat)) == NULL) {
204 ax25_queue_xmit(skb);
211 int ax25_encapsulate(struct sk_buff *skb, struct net_device *dev, unsigned short type, void *daddr, void *saddr, unsigned len)
213 return -AX25_HEADER_LEN;
216 int ax25_rebuild_header(struct sk_buff *skb)