diff options
Diffstat (limited to 'drivers/net/hamradio/mkiss.c')
| -rw-r--r-- | drivers/net/hamradio/mkiss.c | 951 |
1 files changed, 951 insertions, 0 deletions
diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c new file mode 100644 index 00000000000..d9ea080aea0 --- /dev/null +++ b/drivers/net/hamradio/mkiss.c @@ -0,0 +1,951 @@ +/* + * MKISS Driver + * + * 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. + * + * This module implements the AX.25 protocol for kernel-based + * devices like TTYs. It interfaces between a raw TTY, and the + * kernel's AX.25 protocol layers, just like slip.c. + * AX.25 needs to be separated from slip.c while slip.c is no + * longer a static kernel device since it is a module. + * This method clears the way to implement other kiss protocols + * like mkiss smack g8bpq ..... so far only mkiss is implemented. + * + * Hans Alblas <hans@esrac.ele.tue.nl> + * + * History + * Jonathan (G4KLX) Fixed to match Linux networking changes - 2.1.15. + * Matthias (DG2FEF) Added support for FlexNet CRC (on special request) + * Fixed bug in ax25_close(): dev_lock_wait() was + * called twice, causing a deadlock. + * Jeroen (PE1RXQ) Removed old MKISS_MAGIC stuff and calls to + * MOD_*_USE_COUNT + * Remove cli() and fix rtnl lock usage. + */ + +#include <linux/config.h> +#include <linux/module.h> +#include <asm/system.h> +#include <linux/bitops.h> +#include <asm/uaccess.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/in.h> +#include <linux/inet.h> +#include <linux/tty.h> +#include <linux/errno.h> +#include <linux/netdevice.h> +#include <linux/major.h> +#include <linux/init.h> +#include <linux/rtnetlink.h> +#include <linux/etherdevice.h> +#include <linux/skbuff.h> +#include <linux/if_arp.h> + +#include <net/ax25.h> + +#include "mkiss.h" + +#ifdef CONFIG_INET +#include <linux/ip.h> +#include <linux/tcp.h> +#endif + +static char banner[] __initdata = KERN_INFO "mkiss: AX.25 Multikiss, Hans Albas PE1AYX\n"; + +typedef struct ax25_ctrl { + struct ax_disp ctrl; /* */ + struct net_device dev; /* the device */ +} ax25_ctrl_t; + +static ax25_ctrl_t **ax25_ctrls; + +int ax25_maxdev = AX25_MAXDEV; /* Can be overridden with insmod! */ + +static struct tty_ldisc ax_ldisc; + +static int ax25_init(struct net_device *); +static int kiss_esc(unsigned char *, unsigned char *, int); +static int kiss_esc_crc(unsigned char *, unsigned char *, unsigned short, int); +static void kiss_unesc(struct ax_disp *, unsigned char); + +/*---------------------------------------------------------------------------*/ + +static const unsigned short Crc_flex_table[] = { + 0x0f87, 0x1e0e, 0x2c95, 0x3d1c, 0x49a3, 0x582a, 0x6ab1, 0x7b38, + 0x83cf, 0x9246, 0xa0dd, 0xb154, 0xc5eb, 0xd462, 0xe6f9, 0xf770, + 0x1f06, 0x0e8f, 0x3c14, 0x2d9d, 0x5922, 0x48ab, 0x7a30, 0x6bb9, + 0x934e, 0x82c7, 0xb05c, 0xa1d5, 0xd56a, 0xc4e3, 0xf678, 0xe7f1, + 0x2e85, 0x3f0c, 0x0d97, 0x1c1e, 0x68a1, 0x7928, 0x4bb3, 0x5a3a, + 0xa2cd, 0xb344, 0x81df, 0x9056, 0xe4e9, 0xf560, 0xc7fb, 0xd672, + 0x3e04, 0x2f8d, 0x1d16, 0x0c9f, 0x7820, 0x69a9, 0x5b32, 0x4abb, + 0xb24c, 0xa3c5, 0x915e, 0x80d7, 0xf468, 0xe5e1, 0xd77a, 0xc6f3, + 0x4d83, 0x5c0a, 0x6e91, 0x7f18, 0x0ba7, 0x1a2e, 0x28b5, 0x393c, + 0xc1cb, 0xd042, 0xe2d9, 0xf350, 0x87ef, 0x9666, 0xa4fd, 0xb574, + 0x5d02, 0x4c8b, 0x7e10, 0x6f99, 0x1b26, 0x0aaf, 0x3834, 0x29bd, + 0xd14a, 0xc0c3, 0xf258, 0xe3d1, 0x976e, 0x86e7, 0xb47c, 0xa5f5, + 0x6c81, 0x7d08, 0x4f93, 0x5e1a, 0x2aa5, 0x3b2c, 0x09b7, 0x183e, + 0xe0c9, 0xf140, 0xc3db, 0xd252, 0xa6ed, 0xb764, 0x85ff, 0x9476, + 0x7c00, 0x6d89, 0x5f12, 0x4e9b, 0x3a24, 0x2bad, 0x1936, 0x08bf, + 0xf048, 0xe1c1, 0xd35a, 0xc2d3, 0xb66c, 0xa7e5, 0x957e, 0x84f7, + 0x8b8f, 0x9a06, 0xa89d, 0xb914, 0xcdab, 0xdc22, 0xeeb9, 0xff30, + 0x07c7, 0x164e, 0x24d5, 0x355c, 0x41e3, 0x506a, 0x62f1, 0x7378, + 0x9b0e, 0x8a87, 0xb81c, 0xa995, 0xdd2a, 0xcca3, 0xfe38, 0xefb1, + 0x1746, 0x06cf, 0x3454, 0x25dd, 0x5162, 0x40eb, 0x7270, 0x63f9, + 0xaa8d, 0xbb04, 0x899f, 0x9816, 0xeca9, 0xfd20, 0xcfbb, 0xde32, + 0x26c5, 0x374c, 0x05d7, 0x145e, 0x60e1, 0x7168, 0x43f3, 0x527a, + 0xba0c, 0xab85, 0x991e, 0x8897, 0xfc28, 0xeda1, 0xdf3a, 0xceb3, + 0x3644, 0x27cd, 0x1556, 0x04df, 0x7060, 0x61e9, 0x5372, 0x42fb, + 0xc98b, 0xd802, 0xea99, 0xfb10, 0x8faf, 0x9e26, 0xacbd, 0xbd34, + 0x45c3, 0x544a, 0x66d1, 0x7758, 0x03e7, 0x126e, 0x20f5, 0x317c, + 0xd90a, 0xc883, 0xfa18, 0xeb91, 0x9f2e, 0x8ea7, 0xbc3c, 0xadb5, + 0x5542, 0x44cb, 0x7650, 0x67d9, 0x1366, 0x02ef, 0x3074, 0x21fd, + 0xe889, 0xf900, 0xcb9b, 0xda12, 0xaead, 0xbf24, 0x8dbf, 0x9c36, + 0x64c1, 0x7548, 0x47d3, 0x565a, 0x22e5, 0x336c, 0x01f7, 0x107e, + 0xf808, 0xe981, 0xdb1a, 0xca93, 0xbe2c, 0xafa5, 0x9d3e, 0x8cb7, + 0x7440, 0x65c9, 0x5752, 0x46db, 0x3264, 0x23ed, 0x1176, 0x00ff +}; + +/*---------------------------------------------------------------------------*/ + +static unsigned short calc_crc_flex(unsigned char *cp, int size) +{ + unsigned short crc = 0xffff; + + while (size--) + crc = (crc << 8) ^ Crc_flex_table[((crc >> 8) ^ *cp++) & 0xff]; + + return crc; +} + +/*---------------------------------------------------------------------------*/ + +static int check_crc_flex(unsigned char *cp, int size) +{ + unsigned short crc = 0xffff; + + if (size < 3) + return -1; + + while (size--) + crc = (crc << 8) ^ Crc_flex_table[((crc >> 8) ^ *cp++) & 0xff]; + + if ((crc & 0xffff) != 0x7070) + return -1; + + return 0; +} + +/*---------------------------------------------------------------------------*/ + +/* Find a free channel, and link in this `tty' line. */ +static inline struct ax_disp *ax_alloc(void) +{ + ax25_ctrl_t *axp=NULL; + int i; + + for (i = 0; i < ax25_maxdev; i++) { + axp = ax25_ctrls[i]; + + /* Not allocated ? */ + if (axp == NULL) + break; + + /* Not in use ? */ + if (!test_and_set_bit(AXF_INUSE, &axp->ctrl.flags)) + break; + } + + /* Sorry, too many, all slots in use */ + if (i >= ax25_maxdev) + return NULL; + + /* If no channels are available, allocate one */ + if (axp == NULL && (ax25_ctrls[i] = kmalloc(sizeof(ax25_ctrl_t), GFP_KERNEL)) != NULL) { + axp = ax25_ctrls[i]; + } + memset(axp, 0, sizeof(ax25_ctrl_t)); + + /* Initialize channel control data */ + set_bit(AXF_INUSE, &axp->ctrl.flags); + sprintf(axp->dev.name, "ax%d", i++); + axp->ctrl.tty = NULL; + axp->dev.base_addr = i; + axp->dev.priv = (void *)&axp->ctrl; + axp->dev.next = NULL; + axp->dev.init = ax25_init; + + if (axp != NULL) { + /* + * register device so that it can be ifconfig'ed + * ax25_init() will be called as a side-effect + * SIDE-EFFECT WARNING: ax25_init() CLEARS axp->ctrl ! + */ + if (register_netdev(&axp->dev) == 0) { + /* (Re-)Set the INUSE bit. Very Important! */ + set_bit(AXF_INUSE, &axp->ctrl.flags); + axp->ctrl.dev = &axp->dev; + axp->dev.priv = (void *) &axp->ctrl; + + return &axp->ctrl; + } else { + clear_bit(AXF_INUSE,&axp->ctrl.flags); + printk(KERN_ERR "mkiss: ax_alloc() - register_netdev() failure.\n"); + } + } + + return NULL; +} + +/* Free an AX25 channel. */ +static inline void ax_free(struct ax_disp *ax) +{ + /* Free all AX25 frame buffers. */ + if (ax->rbuff) + kfree(ax->rbuff); + ax->rbuff = NULL; + if (ax->xbuff) + kfree(ax->xbuff); + ax->xbuff = NULL; + if (!test_and_clear_bit(AXF_INUSE, &ax->flags)) + printk(KERN_ERR "mkiss: %s: ax_free for already free unit.\n", ax->dev->name); +} + +static void ax_changedmtu(struct ax_disp *ax) +{ + struct net_device *dev = ax->dev; + unsigned char *xbuff, *rbuff, *oxbuff, *orbuff; + int len; + + len = dev->mtu * 2; + + /* + * allow for arrival of larger UDP packets, even if we say not to + * also fixes a bug in which SunOS sends 512-byte packets even with + * an MSS of 128 + */ + if (len < 576 * 2) + len = 576 * 2; + + xbuff = kmalloc(len + 4, GFP_ATOMIC); + rbuff = kmalloc(len + 4, GFP_ATOMIC); + + if (xbuff == NULL || rbuff == NULL) { + printk(KERN_ERR "mkiss: %s: unable to grow ax25 buffers, MTU change cancelled.\n", + ax->dev->name); + dev->mtu = ax->mtu; + if (xbuff != NULL) + kfree(xbuff); + if (rbuff != NULL) + kfree(rbuff); + return; + } + + spin_lock_bh(&ax->buflock); + + oxbuff = ax->xbuff; + ax->xbuff = xbuff; + orbuff = ax->rbuff; + ax->rbuff = rbuff; + + if (ax->xleft) { + if (ax->xleft <= len) { + memcpy(ax->xbuff, ax->xhead, ax->xleft); + } else { + ax->xleft = 0; + ax->tx_dropped++; + } + } + + ax->xhead = ax->xbuff; + + if (ax->rcount) { + if (ax->rcount <= len) { + memcpy(ax->rbuff, orbuff, ax->rcount); + } else { + ax->rcount = 0; + ax->rx_over_errors++; + set_bit(AXF_ERROR, &ax->flags); + } + } + + ax->mtu = dev->mtu + 73; + ax->buffsize = len; + + spin_unlock_bh(&ax->buflock); + + if (oxbuff != NULL) + kfree(oxbuff); + if (orbuff != NULL) + kfree(orbuff); +} + + +/* Set the "sending" flag. This must be atomic. */ +static inline void ax_lock(struct ax_disp *ax) +{ + netif_stop_queue(ax->dev); +} + + +/* Clear the "sending" flag. This must be atomic. */ +static inline void ax_unlock(struct ax_disp *ax) +{ + netif_start_queue(ax->dev); +} + +/* Send one completely decapsulated AX.25 packet to the AX.25 layer. */ +static void ax_bump(struct ax_disp *ax) +{ + struct sk_buff *skb; + int count; + + spin_lock_bh(&ax->buflock); + if (ax->rbuff[0] > 0x0f) { + if (ax->rbuff[0] & 0x20) { + ax->crcmode = CRC_MODE_FLEX; + if (check_crc_flex(ax->rbuff, ax->rcount) < 0) { + ax->rx_errors++; + return; + } + ax->rcount -= 2; + /* dl9sau bugfix: the trailling two bytes flexnet crc + * will not be passed to the kernel. thus we have + * to correct the kissparm signature, because it + * indicates a crc but there's none + */ + *ax->rbuff &= ~0x20; + } + } + spin_unlock_bh(&ax->buflock); + + count = ax->rcount; + + if ((skb = dev_alloc_skb(count)) == NULL) { + printk(KERN_ERR "mkiss: %s: memory squeeze, dropping packet.\n", ax->dev->name); + ax->rx_dropped++; + return; + } + + skb->dev = ax->dev; + spin_lock_bh(&ax->buflock); + memcpy(skb_put(skb,count), ax->rbuff, count); + spin_unlock_bh(&ax->buflock); + skb->mac.raw = skb->data; + skb->protocol = htons(ETH_P_AX25); + netif_rx(skb); + ax->dev->last_rx = jiffies; + ax->rx_packets++; + ax->rx_bytes+=count; +} + +/* Encapsulate one AX.25 packet and stuff into a TTY queue. */ +static void ax_encaps(struct ax_disp *ax, unsigned char *icp, int len) +{ + unsigned char *p; + int actual, count; + + if (ax->mtu != ax->dev->mtu + 73) /* Someone has been ifconfigging */ + ax_changedmtu(ax); + + if (len > ax->mtu) { /* Sigh, shouldn't occur BUT ... */ + len = ax->mtu; + printk(KERN_ERR "mkiss: %s: truncating oversized transmit packet!\n", ax->dev->name); + ax->tx_dropped++; + ax_unlock(ax); + return; + } + + p = icp; + + spin_lock_bh(&ax->buflock); + switch (ax->crcmode) { + unsigned short crc; + + case CRC_MODE_FLEX: + *p |= 0x20; + crc = calc_crc_flex(p, len); + count = kiss_esc_crc(p, (unsigned char *)ax->xbuff, crc, len+2); + break; + + default: + count = kiss_esc(p, (unsigned char *)ax->xbuff, len); + break; + } + + ax->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP); + actual = ax->tty->driver->write(ax->tty, ax->xbuff, count); + ax->tx_packets++; + ax->tx_bytes+=actual; + ax->dev->trans_start = jiffies; + ax->xleft = count - actual; + ax->xhead = ax->xbuff + actual; + + spin_unlock_bh(&ax->buflock); +} + +/* + * Called by the driver when there's room for more data. If we have + * more packets to send, we send them here. + */ +static void ax25_write_wakeup(struct tty_struct *tty) +{ + int actual; + struct ax_disp *ax = (struct ax_disp *) tty->disc_data; + + /* First make sure we're connected. */ + if (ax == NULL || ax->magic != AX25_MAGIC || !netif_running(ax->dev)) + return; + if (ax->xleft <= 0) { + /* Now serial buffer is almost free & we can start + * transmission of another packet + */ + tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); + + netif_wake_queue(ax->dev); + return; + } + + actual = tty->driver->write(tty, ax->xhead, ax->xleft); + ax->xleft -= actual; + ax->xhead += actual; +} + +/* Encapsulate an AX.25 packet and kick it into a TTY queue. */ +static int ax_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct ax_disp *ax = netdev_priv(dev); + + if (!netif_running(dev)) { + printk(KERN_ERR "mkiss: %s: xmit call when iface is down\n", dev->name); + return 1; + } + + if (netif_queue_stopped(dev)) { + /* + * May be we must check transmitter timeout here ? + * 14 Oct 1994 Dmitry Gorodchanin. + */ + if (jiffies - dev->trans_start < 20 * HZ) { + /* 20 sec timeout not reached */ + return 1; + } + + printk(KERN_ERR "mkiss: %s: transmit timed out, %s?\n", dev->name, + (ax->tty->driver->chars_in_buffer(ax->tty) || ax->xleft) ? + "bad line quality" : "driver error"); + + ax->xleft = 0; + ax->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); + ax_unlock(ax); + } + + /* We were not busy, so we are now... :-) */ + if (skb != NULL) { + ax_lock(ax); + ax_encaps(ax, skb->data, skb->len); + kfree_skb(skb); + } + + return 0; +} + +#if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE) + +/* Return the frame type ID */ +static int ax_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, + void *daddr, void *saddr, unsigned len) +{ +#ifdef CONFIG_INET + if (type != htons(ETH_P_AX25)) + return ax25_encapsulate(skb, dev, type, daddr, saddr, len); +#endif + return 0; +} + + +static int ax_rebuild_header(struct sk_buff *skb) +{ +#ifdef CONFIG_INET + return ax25_rebuild_header(skb); +#else + return 0; +#endif +} + +#endif /* CONFIG_{AX25,AX25_MODULE} */ + +/* Open the low-level part of the AX25 channel. Easy! */ +static int ax_open(struct net_device *dev) +{ + struct ax_disp *ax = netdev_priv(dev); + unsigned long len; + + if (ax->tty == NULL) + return -ENODEV; + + /* + * Allocate the frame buffers: + * + * rbuff Receive buffer. + * xbuff Transmit buffer. + */ + len = dev->mtu * 2; + + /* + * allow for arrival of larger UDP packets, even if we say not to + * also fixes a bug in which SunOS sends 512-byte packets even with + * an MSS of 128 + */ + if (len < 576 * 2) + len = 576 * 2; + + if ((ax->rbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL) + goto norbuff; + + if ((ax->xbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL) + goto noxbuff; + + ax->mtu = dev->mtu + 73; + ax->buffsize = len; + ax->rcount = 0; + ax->xleft = 0; + + ax->flags &= (1 << AXF_INUSE); /* Clear ESCAPE & ERROR flags */ + + spin_lock_init(&ax->buflock); + + netif_start_queue(dev); + return 0; + +noxbuff: + kfree(ax->rbuff); + +norbuff: + return -ENOMEM; +} + + +/* Close the low-level part of the AX25 channel. Easy! */ +static int ax_close(struct net_device *dev) +{ + struct ax_disp *ax = netdev_priv(dev); + + if (ax->tty == NULL) + return -EBUSY; + + ax->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); + + netif_stop_queue(dev); + + return 0; +} + +static int ax25_receive_room(struct tty_struct *tty) +{ + return 65536; /* We can handle an infinite amount of data. :-) */ +} + +/* + * Handle the 'receiver data ready' interrupt. + * This function is called by the 'tty_io' module in the kernel when + * a block of data has been received, which can now be decapsulated + * and sent on to the AX.25 layer for further processing. + */ +static void ax25_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) +{ + struct ax_disp *ax = (struct ax_disp *) tty->disc_data; + + if (ax == NULL || ax->magic != AX25_MAGIC || !netif_running(ax->dev)) + return; + + /* + * Argh! mtu change time! - costs us the packet part received + * at the change + */ + if (ax->mtu != ax->dev->mtu + 73) + ax_changedmtu(ax); + + /* Read the characters out of the buffer */ + while (count--) { + if (fp != NULL && *fp++) { + if (!test_and_set_bit(AXF_ERROR, &ax->flags)) + ax->rx_errors++; + cp++; + continue; + } + + kiss_unesc(ax, *cp++); + } +} + +static int ax25_open(struct tty_struct *tty) +{ + struct ax_disp *ax = (struct ax_disp *) tty->disc_data; + int err; + + /* First make sure we're not already connected. */ + if (ax && ax->magic == AX25_MAGIC) + return -EEXIST; + + /* OK. Find a free AX25 channel to use. */ + if ((ax = ax_alloc()) == NULL) + return -ENFILE; + + ax->tty = tty; + tty->disc_data = ax; + + if (tty->driver->flush_buffer) + tty->driver->flush_buffer(tty); + + /* Restore default settings */ + ax->dev->type = ARPHRD_AX25; + + /* Perform the low-level AX25 initialization. */ + if ((err = ax_open(ax->dev))) + return err; + + /* Done. We have linked the TTY line to a channel. */ + return ax->dev->base_addr; +} + +static void ax25_close(struct tty_struct *tty) +{ + struct ax_disp *ax = (struct ax_disp *) tty->disc_data; + + /* First make sure we're connected. */ + if (ax == NULL || ax->magic != AX25_MAGIC) + return; + + unregister_netdev(ax->dev); + + tty->disc_data = NULL; + ax->tty = NULL; + + ax_free(ax); +} + + +static struct net_device_stats *ax_get_stats(struct net_device *dev) +{ + static struct net_device_stats stats; + struct ax_disp *ax = netdev_priv(dev); + + memset(&stats, 0, sizeof(struct net_device_stats)); + + stats.rx_packets = ax->rx_packets; + stats.tx_packets = ax->tx_packets; + stats.rx_bytes = ax->rx_bytes; + stats.tx_bytes = ax->tx_bytes; + stats.rx_dropped = ax->rx_dropped; + stats.tx_dropped = ax->tx_dropped; + stats.tx_errors = ax->tx_errors; + stats.rx_errors = ax->rx_errors; + stats.rx_over_errors = ax->rx_over_errors; + + return &stats; +} + + +/************************************************************************ + * STANDARD ENCAPSULATION * + ************************************************************************/ + +static int kiss_esc(unsigned char *s, unsigned char *d, int len) +{ + unsigned char *ptr = d; + unsigned char c; + + /* + * Send an initial END character to flush out any + * data that may have accumulated in the receiver + * due to line noise. + */ + + *ptr++ = END; + + while (len-- > 0) { + switch (c = *s++) { + case END: + *ptr++ = ESC; + *ptr++ = ESC_END; + break; + case ESC: + *ptr++ = ESC; + *ptr++ = ESC_ESC; + break; + default: + *ptr++ = c; + break; + } + } + + *ptr++ = END; + + return ptr - d; +} + +/* + * MW: + * OK its ugly, but tell me a better solution without copying the + * packet to a temporary buffer :-) + */ +static int kiss_esc_crc(unsigned char *s, unsigned char *d, unsigned short crc, int len) +{ + unsigned char *ptr = d; + unsigned char c=0; + + *ptr++ = END; + while (len > 0) { + if (len > 2) + c = *s++; + else if (len > 1) + c = crc >> 8; + else if (len > 0) + c = crc & 0xff; + + len--; + + switch (c) { + case END: + *ptr++ = ESC; + *ptr++ = ESC_END; + break; + case ESC: + *ptr++ = ESC; + *ptr++ = ESC_ESC; + break; + default: + *ptr++ = c; + break; + } + } + *ptr++ = END; + return ptr - d; +} + +static void kiss_unesc(struct ax_disp *ax, unsigned char s) +{ + switch (s) { + case END: + /* drop keeptest bit = VSV */ + if (test_bit(AXF_KEEPTEST, &ax->flags)) + clear_bit(AXF_KEEPTEST, &ax->flags); + + if (!test_and_clear_bit(AXF_ERROR, &ax->flags) && (ax->rcount > 2)) + ax_bump(ax); + + clear_bit(AXF_ESCAPE, &ax->flags); + ax->rcount = 0; + return; + + case ESC: + set_bit(AXF_ESCAPE, &ax->flags); + return; + case ESC_ESC: + if (test_and_clear_bit(AXF_ESCAPE, &ax->flags)) + s = ESC; + break; + case ESC_END: + if (test_and_clear_bit(AXF_ESCAPE, &ax->flags)) + s = END; + break; + } + + spin_lock_bh(&ax->buflock); + if (!test_bit(AXF_ERROR, &ax->flags)) { + if (ax->rcount < ax->buffsize) { + ax->rbuff[ax->rcount++] = s; + spin_unlock_bh(&ax->buflock); + return; + } + + ax->rx_over_errors++; + set_bit(AXF_ERROR, &ax->flags); + } + spin_unlock_bh(&ax->buflock); +} + + +static int ax_set_mac_address(struct net_device *dev, void __user *addr) +{ + if (copy_from_user(dev->dev_addr, addr, AX25_ADDR_LEN)) + return -EFAULT; + return 0; +} + +static int ax_set_dev_mac_address(struct net_device *dev, void *addr) +{ + struct sockaddr *sa = addr; + + memcpy(dev->dev_addr, sa->sa_data, AX25_ADDR_LEN); + + return 0; +} + + +/* Perform I/O control on an active ax25 channel. */ +static int ax25_disp_ioctl(struct tty_struct *tty, void *file, int cmd, void __user *arg) +{ + struct ax_disp *ax = (struct ax_disp *) tty->disc_data; + unsigned int tmp; + + /* First make sure we're connected. */ + if (ax == NULL || ax->magic != AX25_MAGIC) + return -EINVAL; + + switch (cmd) { + case SIOCGIFNAME: + if (copy_to_user(arg, ax->dev->name, strlen(ax->dev->name) + 1)) + return -EFAULT; + return 0; + + case SIOCGIFENCAP: + return put_user(4, (int __user *)arg); + + case SIOCSIFENCAP: + if (get_user(tmp, (int __user *)arg)) + return -EFAULT; + ax->mode = tmp; + ax->dev->addr_len = AX25_ADDR_LEN; /* sizeof an AX.25 addr */ + ax->dev->hard_header_len = AX25_KISS_HEADER_LEN + AX25_MAX_HEADER_LEN + 3; + ax->dev->type = ARPHRD_AX25; + return 0; + + case SIOCSIFHWADDR: + return ax_set_mac_address(ax->dev, arg); + + default: + return -ENOIOCTLCMD; + } +} + +static int ax_open_dev(struct net_device *dev) +{ + struct ax_disp *ax = netdev_priv(dev); + + if (ax->tty == NULL) + return -ENODEV; + + return 0; +} + + +/* Initialize the driver. Called by network startup. */ +static int ax25_init(struct net_device *dev) +{ + struct ax_disp *ax = netdev_priv(dev); + + static char ax25_bcast[AX25_ADDR_LEN] = + {'Q'<<1,'S'<<1,'T'<<1,' '<<1,' '<<1,' '<<1,'0'<<1}; + static char ax25_test[AX25_ADDR_LEN] = + {'L'<<1,'I'<<1,'N'<<1,'U'<<1,'X'<<1,' '<<1,'1'<<1}; + + if (ax == NULL) /* Allocation failed ?? */ + return -ENODEV; + + /* Set up the "AX25 Control Block". (And clear statistics) */ + memset(ax, 0, sizeof (struct ax_disp)); + ax->magic = AX25_MAGIC; + ax->dev = dev; + + /* Finish setting up the DEVICE info. */ + dev->mtu = AX_MTU; + dev->hard_start_xmit = ax_xmit; + dev->open = ax_open_dev; + dev->stop = ax_close; + dev->get_stats = ax_get_stats; + dev->set_mac_address = ax_set_dev_mac_address; + dev->hard_header_len = 0; + dev->addr_len = 0; + dev->type = ARPHRD_AX25; + dev->tx_queue_len = 10; + dev->hard_header = ax_header; + dev->rebuild_header = ax_rebuild_header; + + memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN); + memcpy(dev->dev_addr, ax25_test, AX25_ADDR_LEN); + + /* New-style flags. */ + dev->flags = IFF_BROADCAST | IFF_MULTICAST; + + return 0; +} + + +/* ******************************************************************** */ +/* * Init MKISS driver * */ +/* ******************************************************************** */ + +static int __init mkiss_init_driver(void) +{ + int status; + + printk(banner); + + if (ax25_maxdev < 4) + ax25_maxdev = 4; /* Sanity */ + + if ((ax25_ctrls = kmalloc(sizeof(void *) * ax25_maxdev, GFP_KERNEL)) == NULL) { + printk(KERN_ERR "mkiss: Can't allocate ax25_ctrls[] array!\n"); + return -ENOMEM; + } + + /* Clear the pointer array, we allocate devices when we need them */ + memset(ax25_ctrls, 0, sizeof(void*) * ax25_maxdev); /* Pointers */ + + /* Fill in our line protocol discipline, and register it */ + ax_ldisc.magic = TTY_LDISC_MAGIC; + ax_ldisc.name = "mkiss"; + ax_ldisc.open = ax25_open; + ax_ldisc.close = ax25_close; + ax_ldisc.ioctl = (int (*)(struct tty_struct *, struct file *, + unsigned int, unsigned long))ax25_disp_ioctl; + ax_ldisc.receive_buf = ax25_receive_buf; + ax_ldisc.receive_room = ax25_receive_room; + ax_ldisc.write_wakeup = ax25_write_wakeup; + + if ((status = tty_register_ldisc(N_AX25, &ax_ldisc)) != 0) { + printk(KERN_ERR "mkiss: can't register line discipline (err = %d)\n", status); + kfree(ax25_ctrls); + } + return status; +} + +static void __exit mkiss_exit_driver(void) +{ + int i; + + for (i = 0; i < ax25_maxdev; i++) { + if (ax25_ctrls[i]) { + /* + * VSV = if dev->start==0, then device + * unregistered while close proc. + */ + if (netif_running(&ax25_ctrls[i]->dev)) + unregister_netdev(&ax25_ctrls[i]->dev); + kfree(ax25_ctrls[i]); + } + } + + kfree(ax25_ctrls); + ax25_ctrls = NULL; + + if ((i = tty_register_ldisc(N_AX25, NULL))) + printk(KERN_ERR "mkiss: can't unregister line discipline (err = %d)\n", i); +} + +MODULE_AUTHOR("Hans Albas PE1AYX <hans@esrac.ele.tue.nl>"); +MODULE_DESCRIPTION("KISS driver for AX.25 over TTYs"); +MODULE_PARM(ax25_maxdev, "i"); +MODULE_PARM_DESC(ax25_maxdev, "number of MKISS devices"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_LDISC(N_AX25); +module_init(mkiss_init_driver); +module_exit(mkiss_exit_driver); + |