common.h

/*
 * Common interfaces for XRadio drivers
 *
 * Copyright (c) 2013, XRadio
 * Author: XRadio
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef XRADIO_COMMON_H
#define XRADIO_COMMON_H

/*******************************************************
 interfaces for parse frame protocol info.
********************************************************/
#define LLC_LEN       8
#define LLC_TYPE_OFF  6  //Ether type offset
#define IP_PROTO_OFF  9  //protocol offset
#define IP_S_ADD_OFF  12
#define IP_D_ADD_OFF  16
#define UDP_LEN       8
//DHCP
#define DHCP_BOOTP_C  68
#define DHCP_BOOTP_S  67
#define UDP_BOOTP_LEN 236  //exclude "Options:64"
#define BOOTP_OPS_LEN 64
#define DHCP_MAGIC    0x63825363
#define DHCP_DISCOVER 0x01
#define DHCP_OFFER    0x02
#define DHCP_REQUEST  0x03
#define DHCP_DECLINE  0x04
#define DHCP_ACK      0x05
#define DHCP_NACK     0x06
#define DHCP_RELEASE  0x07

//LLC layer.
static inline bool is_SNAP(u8* llc_data)
{
	return (bool)(*(u16*)(llc_data) == 0xAAAA && llc_data[2] == 0x03);  //0xAA, 0xAA, 0x03.
}

static inline bool is_STP(u8* llc_data)
{
	return (bool)(*(u16*)(llc_data) == 0xAAAA && llc_data[2] == 0x03);  //0x42, 0x42, 0x03.
}

//IP/IPV6/ARP layer...
static inline bool is_ip(u8* llc_data)
{
	return (bool)(*(u16*)(llc_data+LLC_TYPE_OFF) == cpu_to_be16(ETH_P_IP));   //0x0800
}
static inline bool is_ipv6(u8* llc_data)
{
	return (bool)(*(u16*)(llc_data+LLC_TYPE_OFF) == cpu_to_be16(ETH_P_IPV6)); //0x08dd
}
static inline bool is_arp(u8* llc_data)
{
	return (bool)(*(u16*)(llc_data+LLC_TYPE_OFF) == cpu_to_be16(ETH_P_ARP));  //0x0806
}
static inline bool is_8021x(u8* llc_data)
{
	return (bool)(*(u16*)(llc_data+LLC_TYPE_OFF) == cpu_to_be16(ETH_P_PAE));  //0x888E
}

//TCP/UDP layer...
static inline bool is_tcp(u8* llc_data)
{
	return (bool)(llc_data[LLC_LEN+IP_PROTO_OFF] == IPPROTO_TCP);  //
}

static inline bool is_udp(u8* llc_data)
{
	return (bool)(llc_data[LLC_LEN+IP_PROTO_OFF] == IPPROTO_UDP);  //
}

static inline bool is_icmp(u8* llc_data)
{
	return (bool)(llc_data[LLC_LEN+IP_PROTO_OFF] == IPPROTO_ICMP);  //
}

static inline bool is_igmp(u8* llc_data)
{
	return (bool)(llc_data[LLC_LEN+IP_PROTO_OFF] == IPPROTO_IGMP);  //
}

static inline bool is_dhcp(u8* llc_data)
{
	u8* ip_hdr  = llc_data+LLC_LEN;
	if(!is_ip(llc_data))
		return (bool)0;
	if(ip_hdr[IP_PROTO_OFF] == IPPROTO_UDP) {
		u8* udp_hdr = ip_hdr+((ip_hdr[0]&0xf)<<2);  //ihl:words
		return (bool)((((udp_hdr[0]<<8)|udp_hdr[1]) == DHCP_BOOTP_C) ||  //DHCP client
		              (((udp_hdr[0]<<8)|udp_hdr[1]) == DHCP_BOOTP_S));   //DHCP server
	}
	return (bool)0;
}

#endif //XRADIO_COMMON_H