strip.c

linux-2.6.15.6

}

/*
 * This function parses the response to the ATS300? command,
 * extracting the radio version and serial number.
 */
static void get_radio_version(struct strip *strip_info, __u8 * ptr, __u8 * end)
{
	__u8 *p, *value_begin, *value_end;
	int len;

	/* Determine the beginning of the second line of the payload */
	p = ptr;
	while (p < end && *p != 10)
		p++;
	if (p >= end)
		return;
	p++;
	value_begin = p;

	/* Determine the end of line */
	while (p < end && *p != 10)
		p++;
	if (p >= end)
		return;
	value_end = p;
	p++;

	len = value_end - value_begin;
	len = min_t(int, len, sizeof(FirmwareVersion) - 1);
	if (strip_info->firmware_version.c[0] == 0)
		printk(KERN_INFO "%s: Radio Firmware: %.*s\n",
		       strip_info->dev->name, len, value_begin);
	sprintf(strip_info->firmware_version.c, "%.*s", len, value_begin);

	/* Look for the first colon */
	while (p < end && *p != ':')
		p++;
	if (p >= end)
		return;
	/* Skip over the space */
	p += 2;
	len = sizeof(SerialNumber) - 1;
	if (p + len <= end) {
		sprintf(strip_info->serial_number.c, "%.*s", len, p);
	} else {
		printk(KERN_DEBUG
		       "STRIP: radio serial number shorter (%zd) than expected (%d)\n",
		       end - p, len);
	}
}

/*
 * This function parses the response to the ATS325? command,
 * extracting the radio battery voltage.
 */
static void get_radio_voltage(struct strip *strip_info, __u8 * ptr, __u8 * end)
{
	int len;

	len = sizeof(BatteryVoltage) - 1;
	if (ptr + len <= end) {
		sprintf(strip_info->battery_voltage.c, "%.*s", len, ptr);
	} else {
		printk(KERN_DEBUG
		       "STRIP: radio voltage string shorter (%zd) than expected (%d)\n",
		       end - ptr, len);
	}
}

/*
 * This function parses the responses to the AT~LA and ATS311 commands,
 * which list the radio's neighbours.
 */
static void get_radio_neighbours(MetricomNodeTable * table, __u8 * ptr, __u8 * end)
{
	table->num_nodes = 0;
	while (ptr < end && table->num_nodes < NODE_TABLE_SIZE) {
		MetricomNode *node = &table->node[table->num_nodes++];
		char *dst = node->c, *limit = dst + sizeof(*node) - 1;
		while (ptr < end && *ptr <= 32)
			ptr++;
		while (ptr < end && dst < limit && *ptr != 10)
			*dst++ = *ptr++;
		*dst++ = 0;
		while (ptr < end && ptr[-1] != 10)
			ptr++;
	}
	do_gettimeofday(&table->timestamp);
}

static int get_radio_address(struct strip *strip_info, __u8 * p)
{
	MetricomAddress addr;

	if (string_to_radio_address(&addr, p))
		return (1);

	/* See if our radio address has changed */
	if (memcmp(strip_info->true_dev_addr.c, addr.c, sizeof(addr))) {
		MetricomAddressString addr_string;
		radio_address_to_string(&addr, &addr_string);
		printk(KERN_INFO "%s: Radio address = %s\n",
		       strip_info->dev->name, addr_string.c);
		strip_info->true_dev_addr = addr;
		if (!strip_info->manual_dev_addr)
			*(MetricomAddress *) strip_info->dev->dev_addr =
			    addr;
		/* Give the radio a few seconds to get its head straight, then send an arp */
		strip_info->gratuitous_arp = jiffies + 15 * HZ;
		strip_info->arp_interval = 1 * HZ;
	}
	return (0);
}

static int verify_checksum(struct strip *strip_info)
{
	__u8 *p = strip_info->sx_buff;
	__u8 *end = strip_info->sx_buff + strip_info->sx_count - 4;
	u_short sum =
	    (READHEX16(end[0]) << 12) | (READHEX16(end[1]) << 8) |
	    (READHEX16(end[2]) << 4) | (READHEX16(end[3]));
	while (p < end)
		sum -= *p++;
	if (sum == 0 && strip_info->firmware_level == StructuredMessages) {
		strip_info->firmware_level = ChecksummedMessages;
		printk(KERN_INFO "%s: Radio provides message checksums\n",
		       strip_info->dev->name);
	}
	return (sum == 0);
}

static void RecvErr(char *msg, struct strip *strip_info)
{
	__u8 *ptr = strip_info->sx_buff;
	__u8 *end = strip_info->sx_buff + strip_info->sx_count;
	DumpData(msg, strip_info, ptr, end);
	strip_info->rx_errors++;
}

static void RecvErr_Message(struct strip *strip_info, __u8 * sendername,
			    const __u8 * msg, u_long len)
{
	if (has_prefix(msg, len, "001")) {	/* Not in StarMode! */
		RecvErr("Error Msg:", strip_info);
		printk(KERN_INFO "%s: Radio %s is not in StarMode\n",
		       strip_info->dev->name, sendername);
	}

	else if (has_prefix(msg, len, "002")) {	/* Remap handle */
		/* We ignore "Remap handle" messages for now */
	}

	else if (has_prefix(msg, len, "003")) {	/* Can't resolve name */
		RecvErr("Error Msg:", strip_info);
		printk(KERN_INFO "%s: Destination radio name is unknown\n",
		       strip_info->dev->name);
	}

	else if (has_prefix(msg, len, "004")) {	/* Name too small or missing */
		strip_info->watchdog_doreset = jiffies + LongTime;
#if TICKLE_TIMERS
		{
			struct timeval tv;
			do_gettimeofday(&tv);
			printk(KERN_INFO
			       "**** Got ERR_004 response         at %02d.%06d\n",
			       tv.tv_sec % 100, tv.tv_usec);
		}
#endif
		if (!strip_info->working) {
			strip_info->working = TRUE;
			printk(KERN_INFO "%s: Radio now in starmode\n",
			       strip_info->dev->name);
			/*
			 * If the radio has just entered a working state, we should do our first
			 * probe ASAP, so that we find out our radio address etc. without delay.
			 */
			strip_info->watchdog_doprobe = jiffies;
		}
		if (strip_info->firmware_level == NoStructure && sendername) {
			strip_info->firmware_level = StructuredMessages;
			strip_info->next_command = 0;	/* Try to enable checksums ASAP */
			printk(KERN_INFO
			       "%s: Radio provides structured messages\n",
			       strip_info->dev->name);
		}
		if (strip_info->firmware_level >= StructuredMessages) {
			/*
			 * If this message has a valid checksum on the end, then the call to verify_checksum
			 * will elevate the firmware_level to ChecksummedMessages for us. (The actual return
			 * code from verify_checksum is ignored here.)
			 */
			verify_checksum(strip_info);
			/*
			 * If the radio has structured messages but we don't yet have all our information about it,
			 * we should do probes without delay, until we have gathered all the information
			 */
			if (!GOT_ALL_RADIO_INFO(strip_info))
				strip_info->watchdog_doprobe = jiffies;
		}
	}

	else if (has_prefix(msg, len, "005"))	/* Bad count specification */
		RecvErr("Error Msg:", strip_info);

	else if (has_prefix(msg, len, "006"))	/* Header too big */
		RecvErr("Error Msg:", strip_info);

	else if (has_prefix(msg, len, "007")) {	/* Body too big */
		RecvErr("Error Msg:", strip_info);
		printk(KERN_ERR
		       "%s: Error! Packet size too big for radio.\n",
		       strip_info->dev->name);
	}

	else if (has_prefix(msg, len, "008")) {	/* Bad character in name */
		RecvErr("Error Msg:", strip_info);
		printk(KERN_ERR
		       "%s: Radio name contains illegal character\n",
		       strip_info->dev->name);
	}

	else if (has_prefix(msg, len, "009"))	/* No count or line terminator */
		RecvErr("Error Msg:", strip_info);

	else if (has_prefix(msg, len, "010"))	/* Invalid checksum */
		RecvErr("Error Msg:", strip_info);

	else if (has_prefix(msg, len, "011"))	/* Checksum didn't match */
		RecvErr("Error Msg:", strip_info);

	else if (has_prefix(msg, len, "012"))	/* Failed to transmit packet */
		RecvErr("Error Msg:", strip_info);

	else
		RecvErr("Error Msg:", strip_info);
}

static void process_AT_response(struct strip *strip_info, __u8 * ptr,
				__u8 * end)
{
	u_long len;
	__u8 *p = ptr;
	while (p < end && p[-1] != 10)
		p++;		/* Skip past first newline character */
	/* Now ptr points to the AT command, and p points to the text of the response. */
	len = p - ptr;

#if TICKLE_TIMERS
	{
		struct timeval tv;
		do_gettimeofday(&tv);
		printk(KERN_INFO "**** Got AT response %.7s      at %02d.%06d\n",
		       ptr, tv.tv_sec % 100, tv.tv_usec);
	}
#endif

	if (has_prefix(ptr, len, "ATS300?"))
		get_radio_version(strip_info, p, end);
	else if (has_prefix(ptr, len, "ATS305?"))
		get_radio_address(strip_info, p);
	else if (has_prefix(ptr, len, "ATS311?"))
		get_radio_neighbours(&strip_info->poletops, p, end);
	else if (has_prefix(ptr, len, "ATS319=7"))
		verify_checksum(strip_info);
	else if (has_prefix(ptr, len, "ATS325?"))
		get_radio_voltage(strip_info, p, end);
	else if (has_prefix(ptr, len, "AT~LA"))
		get_radio_neighbours(&strip_info->portables, p, end);
	else
		RecvErr("Unknown AT Response:", strip_info);
}

static void process_ACK(struct strip *strip_info, __u8 * ptr, __u8 * end)
{
	/* Currently we don't do anything with ACKs from the radio */
}

static void process_Info(struct strip *strip_info, __u8 * ptr, __u8 * end)
{
	if (ptr + 16 > end)
		RecvErr("Bad Info Msg:", strip_info);
}

static struct net_device *get_strip_dev(struct strip *strip_info)
{
	/* If our hardware address is *manually set* to zero, and we know our */
	/* real radio hardware address, try to find another strip device that has been */
	/* manually set to that address that we can 'transfer ownership' of this packet to  */
	if (strip_info->manual_dev_addr &&
	    !memcmp(strip_info->dev->dev_addr, zero_address.c,
		    sizeof(zero_address))
	    && memcmp(&strip_info->true_dev_addr, zero_address.c,
		      sizeof(zero_address))) {
		struct net_device *dev;
		read_lock_bh(&dev_base_lock);
		dev = dev_base;
		while (dev) {
			if (dev->type == strip_info->dev->type &&
			    !memcmp(dev->dev_addr,
				    &strip_info->true_dev_addr,
				    sizeof(MetricomAddress))) {
				printk(KERN_INFO
				       "%s: Transferred packet ownership to %s.\n",
				       strip_info->dev->name, dev->name);
				read_unlock_bh(&dev_base_lock);
				return (dev);
			}
			dev = dev->next;
		}
		read_unlock_bh(&dev_base_lock);
	}
	return (strip_info->dev);
}

/*
 * Send one completely decapsulated datagram to the next layer.
 */

static void deliver_packet(struct strip *strip_info, STRIP_Header * header,
			   __u16 packetlen)
{
	struct sk_buff *skb = dev_alloc_skb(sizeof(STRIP_Header) + packetlen);
	if (!skb) {
		printk(KERN_ERR "%s: memory squeeze, dropping packet.\n",
		       strip_info->dev->name);
		strip_info->rx_dropped++;
	} else {
		memcpy(skb_put(skb, sizeof(STRIP_Header)), header,
		       sizeof(STRIP_Header));
		memcpy(skb_put(skb, packetlen), strip_info->rx_buff,
		       packetlen);
		skb->dev = get_strip_dev(strip_info);
		skb->protocol = header->protocol;
		skb->mac.raw = skb->data;

		/* Having put a fake header on the front of the sk_buff for the */
		/* benefit of tools like tcpdump, skb_pull now 'consumes' that  */
		/* fake header before we hand the packet up to the next layer.  */
		skb_pull(skb, sizeof(STRIP_Header));

		/* Finally, hand the packet up to the next layer (e.g. IP or ARP, etc.) */
		strip_info->rx_packets++;
		strip_info->rx_pps_count++;
#ifdef EXT_COUNTERS
		strip_info->rx_bytes += packetlen;
#endif
		skb->dev->last_rx = jiffies;
		netif_rx(skb);
	}
}

static void process_IP_packet(struct strip *strip_info,
			      STRIP_Header * header, __u8 * ptr,
			      __u8 * end)
{
	__u16 packetlen;

	/* Decode start of the IP packet header */
	ptr = UnStuffData(ptr, end, strip_info->rx_buff, 4);
	if (!ptr) {
		RecvErr("IP Packet too short", strip_info);
		return;
	}

	packetlen = ((__u16) strip_info->rx_buff[2] << 8) | strip_info->rx_buff[3];

	if (packetlen > MAX_RECV_MTU) {
		printk(KERN_INFO "%s: Dropping oversized received IP packet: %d bytes\n",
		       strip_info->dev->name, packetlen);
		strip_info->rx_dropped++;
		return;
	}

	/*printk(KERN_INFO "%s: Got %d byte IP packet\n", strip_info->dev->name, packetlen); */

	/* Decode remainder of the IP packet */
	ptr =
	    UnStuffData(ptr, end, strip_info->rx_buff + 4, packetlen - 4);
	if (!ptr) {
		RecvErr("IP Packet too short", strip_info);
		return;
	}

	if (ptr < end) {
		RecvErr("IP Packet too long", strip_info);
		return;
	}

	header->protocol = htons(ETH_P_IP);

	deliver_packet(strip_info, header, packetlen);
}

static void process_ARP_packet(struct strip *strip_info,
			       STRIP_Header * header, __u8 * ptr,
			       __u8 * end)
{
	__u16 packetlen;
	struct arphdr *arphdr = (struct arphdr *) strip_info->rx_buff;

	/* Decode start of the ARP packet */
	ptr = UnStuffData(ptr, end, strip_info->rx_buff, 8);
	if (!ptr) {
		RecvErr("ARP Packet too short", strip_info);
		return;
	}

	packetlen = 8 + (arphdr->ar_hln + arphdr->ar_pln) * 2;

	if (packetlen > MAX_RECV_MTU) {
		printk(KERN_INFO
		       "%s: Dropping oversized received ARP packet: %d bytes\n",
		       strip_info->dev->name, packetlen);
		strip_info->rx_dropped+