diff options
Diffstat (limited to 'net/ax25/ax25_ip.c')
| -rw-r--r-- | net/ax25/ax25_ip.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/net/ax25/ax25_ip.c b/net/ax25/ax25_ip.c new file mode 100644 index 000000000..ec882c50d --- /dev/null +++ b/net/ax25/ax25_ip.c @@ -0,0 +1,178 @@ +/* + * AX.25 release 036 + * + * This is ALPHA test software. This code may break your machine, randomly fail to work with new + * releases, misbehave and/or generally screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher/ NET3.038 + * + * This module: + * This module 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. + * + * History + * AX.25 036 Jonathan(G4KLX) Split from af_ax25.c. + */ + +#include <linux/config.h> +#if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE) +#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/if_arp.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <asm/uaccess.h> +#include <asm/system.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/firewall.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 + +int ax25_encapsulate(struct sk_buff *skb, struct device *dev, unsigned short type, void *daddr, void *saddr, unsigned len) +{ + /* header is an AX.25 UI frame from us to them */ + unsigned char *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 wrong protocol type 0x%x2.2\n", type); + *buff++ = 0; + break; + } + + if (daddr != NULL) + return AX25_HEADER_LEN; + + return -AX25_HEADER_LEN; /* Unfinished header */ +} + +int ax25_rebuild_header(struct sk_buff *skb) +{ + struct sk_buff *ourskb; + int mode; + unsigned char *bp = skb->data; + struct device *dev = skb->dev; + ax25_dev *ax25_dev; + + if (arp_find(bp + 1, skb)) + return 1; + + if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) + return 1; + + if (bp[16] == AX25_P_IP) { + mode = ax25_ip_mode_get((ax25_address *)(bp + 1), dev); + if (mode == 'V' || (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. + */ + if ((ourskb = skb_copy(skb, GFP_ATOMIC)) == NULL) { + dev_kfree_skb(skb, FREE_WRITE); + return 1; + } + + if (skb->sk != NULL) + skb_set_owner_w(ourskb, skb->sk); + + kfree_skb(skb, FREE_WRITE); + + skb_pull(ourskb, AX25_HEADER_LEN - 1); /* Keep PID */ + + ax25_send_frame(ourskb, ax25_dev->values[AX25_VALUES_PACLEN], (ax25_address *)(bp + 8), (ax25_address *)(bp + 1), NULL, dev); + + return 1; + } + } + + 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; + + ax25_dg_build_path(skb, (ax25_address *)(bp + 1), dev); + + skb->dev = dev; + skb->priority = SOPRI_NORMAL; + + ax25_queue_xmit(skb); + + return 1; +} + +#endif + +#endif |