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XgIP

Internet Protocol checksum and related support. More...

Data Structures
struct	_ARPENTRY
	ARP entry structure. More...
struct	_ARPENTRY
	ARP entry structure. More...
struct	ifnet
	Network interface structure. More...
struct	ifnet
	Network interface structure. More...
struct	ip
	Structure of an internet header. More...
struct	ip
	Structure of an internet header. More...
struct	pseudo_hdr
Defines
#define	ATF_COM   0x02
	Completed entry.
#define	ATF_PERM   0x04
	Permanent entry.
#define	IPVERSION   4
	IP protocol version.
#define	IP_DF   0x4000
	Don't fragment flag.
#define	IP_MF   0x2000
	More fragments flag.
#define	IP_OFFMASK   0x1fff
	Mask for fragmenting bits.
#define	IPOPT_EOL   0
	End of option list.
#define	IPOPT_NOP   1
	No operation.
#define	IPOPT_RR   7
	Record packet route.
#define	IPOPT_TS   68
	Timestamp.
#define	IPOPT_SECURITY   130
	Provide s,c,h,tcc.
#define	IPOPT_LSRR   131
	Loose source route.
#define	IPOPT_SATID   136
	Satnet id.
#define	IPOPT_SSRR   137
	Strict source route.
#define	IPOPT_OPTVAL   0
	Option identifier offset.
#define	IPOPT_OLEN   1
	Option length offset.
#define	IPOPT_OFFSET   2
	Offset within option.
#define	IPOPT_MINOFF   4
	Minimum offset within option.
#define	MAXTTL   255
	Maximum time to live (seconds).
#define	IPDEFTTL   64
	Default time to live.
#define	IPFRAGTTL   60
	Time to live for fragments.
#define	IPTTLDEC   1
	Subtracted from time to live when forwarding.
Typedefs
typedef _ARPENTRY	ARPENTRY
	ARP entry type.
typedef ifnet	IFNET
	Network interface type.
typedef ip	IPHDR
	Internet header type.
Functions
int	NutNetIfConfig (CONST char *name, void *mac_dev, u_long ip_addr, u_long ip_mask)
	Configure a network interface.
int	NutNetIfSetup (NUTDEVICE *dev, u_long ip_addr, u_long ip_mask, u_long gateway)
int	NutNetLoadConfig (CONST char *name)
	Load network configuration from EEPROM.
int	NutNetSaveConfig (void)
int	NutNetAutoConfig (CONST char *name)
	Configure a network interface using EEPROM values.
int	NutIpOutput (u_char proto, u_long dest, NETBUF *nb)
	Send IP datagram.
void	NutIpInput (NUTDEVICE *dev, NETBUF *nb)
	Process incoming IP datagrams.
u_long	inet_addr (CONST u_char *str)
	Convert decimal dotted ASCII representation into numeric IP address.
u_char *	inet_ntoa (u_long addr)
	Convert numeric IP address into decimal dotted ASCII representation.
u_short	NutIpChkSumPartial (u_short partial_csum, void *buf, u_short count)
	Calculates a partial IP checksum over a block of data.
u_short	NutIpChkSum (u_short partial_csum, void *buf, u_short count)
	Calculates an the final IP checksum over a block of data.
u_short	NutIpPseudoChkSumPartial (u_long src_addr, u_long dest_addr, u_char protocol, u_short len)
	Calculates the partial IP pseudo checksum.
u_short	NutIpPseudoChkSum (u_long src_addr, u_long dest_addr, u_char protocol, u_short len)
	Calculates the IP pseudo checksum.
int	NutIpRouteAdd (u_long ip, u_long mask, u_long gate, NUTDEVICE *dev)
	Add a new entry to the IP routing table.
NUTDEVICE *	NutIpRouteQuery (u_long ip, u_long *gate)
	Find a device associated with a particular IP route.
Variables
RTENTRY *	rteList = 0
	Linked list of routing entries.

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Detailed Description

Internet Protocol checksum and related support.

Author:

Harald Kipp, egnite Software GmbH

Author:

Harald Kipp, egnite Software GmbH

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Function Documentation

u_long inet_addr (  CONST u_char *    str )

Convert decimal dotted ASCII representation into numeric IP address. Parameters: str  String containing the ASCII representation. Returns: IP address in network byte order. Examples: adds/app/mail.

u_char* inet_ntoa (  u_long    addr )

Convert numeric IP address into decimal dotted ASCII representation. Note: This function is not thread safe. Each subsequent call will destroy the previous result. Applications should locally store the result before calling the function again or allowing other threads to call it. Parameters: addr  IP address in network byte order. Returns: Pointer to a static buffer containing the ASCII representation.

u_short NutIpChkSum (  u_short    partial_csum, void *    buf, u_short    count )

Calculates an the final IP checksum over a block of data. Unlike the partial checksum in NutIpChkSumPartial(), this function takes the one's complement of the final result, thus making it the full checksum.

u_short NutIpChkSumPartial (  u_short    partial_csum, void *    buf, u_short    count )

Calculates a partial IP checksum over a block of data. Note that this returns the checksum in network byte order, and thus does not need to be converted via hton16(), etc. Of course this means that we mustn't use this value for normal arithmetic! This is a partial checksum because it doesn't take the 1's complement of the overall sum. Note: by Dave Hudson: This doesn't look particularly intuitive at first sight - in fact it probably looks plain wrong. It does work however (take my word for it), but for some explanation the reader is referred to RFC1071 where the maths is explained in detail. Note: by Harald Kipp: Yes, the GCC version looks wrong. I assume that this will not work for all packet sizes. Not yet confirmed.

void NutIpInput (  NUTDEVICE *    dev, NETBUF *    nb )

Process incoming IP datagrams. Datagrams addressed to other destinations and datagrams whose version number is not 4 are silently discarded. Note: This routine is called by the Ethernet layer on incoming IP datagrams. Applications typically do not call this function. Parameters: dev  Identifies the device that received this datagram. nb  The network buffer received.

int NutIpOutput (  u_char    proto, u_long    dest, NETBUF *    nb )

Send IP datagram. Route an IP datagram to the proper interface. The function will not return until the data has been stored in the network device hardware for transmission. If the device is not ready for transmitting a new packet, the calling thread will be suspended until the device becomes ready again. If the hardware address of the target host needs to be resolved the function will be suspended too. Parameters: proto  Protocol type. dest  Destination IP address. The function will determine the proper network interface by checking the routing table. It will also perform any neccessary hardware address resolution. nb  Network buffer structure containing the datagram. Returns: 0 on success, -1 otherwise. Bug: Broadcasts to multiple network devices are currently not supported.

int NutIpRouteAdd (  u_long    ip, u_long    mask, u_long    gate, NUTDEVICE *    dev )

Add a new entry to the IP routing table. Note, that there is currently no support for removing entries or detecting duplicates. Anyway, newer entries will be found first, because they are inserted in front of older entries. However, this works only for equal masks, i.e. new network routes will never overwrite old host routes. Parameters: ip  Network or host IP address to be route. Set 0 for default route. mask  Mask for this entry. -1 for host routes, 0 for default or net mask for net routes. gate  Route through this gateway, otherwise 0. dev  Network interface to use. Returns: 0 on success, -1 otherwise.

NUTDEVICE* NutIpRouteQuery (  u_long    ip, u_long *    gate )

Find a device associated with a particular IP route. Gateway routes will be automatically resolved up to four levels of redirection. Parameters: ip  IP address to find a route for, given in network byte order. gate  Points to a buffer which optionally receives the IP address of a gateway. The pointer may be NULL, if the caller is not interested in this information. Returns: Pointer to the interface structure or NULL if no route was found.

int NutNetAutoConfig (  CONST char *    name )

Configure a network interface using EEPROM values. Loads IP address, netmask and MAC address from EEPROM and calls NutNetIfConfig(). Parameters: name  Name of the device. Returns: 0 on success, -1 otherwise.

int NutNetIfConfig (  CONST char *    name, void *    mac_dev, u_long    ip_addr, u_long    ip_mask )

Configure a network interface. Open the device and associate the given MAC address, IP address and netmask with the network interface. Parameters: name  Name of the device to configure. This device must have been registered by calling NutRegisterDevice(). mac  6-byte Ethernet MAC address to be used. This must be a unique address within the local Ethernet. The vendor of the Ethernut board will supply an address, which is unique within the known universe. Or for PPP interfaces this is a pointer to the host device or stream that supports this interface. ip_addr  IP address to be used in network byte order. This must be a unique address within the Internet. If you do not directly communicate with other Internet hosts, you can use a locally assigned address. ip_mask  IP network mask to be used in network byte order. Typical networks use 255.255.255.0, which allows upto 254 hosts. Returns: 0 on success, -1 otherwise.

int NutNetIfSetup (  NUTDEVICE *    dev, u_long    ip_addr, u_long    ip_mask, u_long    gateway )

Network interface setup. Parameters: dev  Identifies the network device to setup. This pointer must have been retrieved previously by calling NutDeviceOpen(). ip_addr  ip_mask  gateway  Returns: 0 on success, -1 otherwise. Note: Applications typically do not call this function. It's automatically called by NutNetIfConfig() or indirectly by NutNetAutoConfig().

int NutNetLoadConfig (  CONST char *    name )

Load network configuration from EEPROM. Parameters: name  Name of the device. Returns: 0 if configuration has been read. Otherwise the return value is -1, IP address is 0, IP netmask is 255.255.255.0 and MAC is 00-06-98-00-00-00.

int NutNetSaveConfig (  void    )

Save network configuration in EEPROM.

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