The uIP TCP/IP stack

Collaboration diagram for The uIP TCP/IP stack:

Data Structures
struct	uip_conn
struct	uip_stats
struct	uip_tcpip_hdr
struct	uip_icmpip_hdr
struct	uip_udpip_hdr
struct	uip_eth_addr
Modules
	uIP packet forwarding
	uIP TCP throughput booster hack
	uIP configuration functions
	uIP initialization functions
	uIP device driver functions
	uIP application functions
	uIP conversion functions
	Variables used in uIP device drivers
	uIP Address Resolution Protocol
	Architecture specific uIP functions
Files
file	uip.c
file	uip.h
Defines
#define	TCP_FIN 0x01
#define	TCP_SYN 0x02
#define	TCP_RST 0x04
#define	TCP_PSH 0x08
#define	TCP_ACK 0x10
#define	TCP_URG 0x20
#define	TCP_CTL 0x3f
#define	TCP_OPT_END 0
#define	TCP_OPT_NOOP 1
#define	TCP_OPT_MSS 2
#define	TCP_OPT_MSS_LEN 4
#define	ICMP_ECHO_REPLY 0
#define	ICMP_ECHO 8
#define	ICMP6_ECHO_REPLY 129
#define	ICMP6_ECHO 128
#define	ICMP6_NEIGHBOR_SOLICITATION 135
#define	ICMP6_NEIGHBOR_ADVERTISEMENT 136
#define	ICMP6_FLAG_S (1 << 6)
#define	ICMP6_OPTION_SOURCE_LINK_ADDRESS 1
#define	ICMP6_OPTION_TARGET_LINK_ADDRESS 2
#define	BUF ((struct uip_tcpip_hdr *)&uip_buf[UIP_LLH_LEN])
#define	FBUF ((struct uip_tcpip_hdr *)&uip_reassbuf[0])
#define	ICMPBUF ((struct uip_icmpip_hdr *)&uip_buf[UIP_LLH_LEN])
#define	UDPBUF ((struct uip_udpip_hdr *)&uip_buf[UIP_LLH_LEN])
#define	UIP_STAT(s)
#define	UIP_LOG(m)
#define	UIP_ACKDATA 1
#define	UIP_NEWDATA 2
#define	UIP_REXMIT 4
#define	UIP_POLL 8
#define	UIP_CLOSE 16
#define	UIP_ABORT 32
#define	UIP_CONNECTED 64
#define	UIP_TIMEDOUT 128
#define	UIP_DATA 1
#define	UIP_TIMER 2
#define	UIP_POLL_REQUEST 3
#define	UIP_UDP_SEND_CONN 4
#define	UIP_CLOSED 0
#define	UIP_SYN_RCVD 1
#define	UIP_SYN_SENT 2
#define	UIP_ESTABLISHED 3
#define	UIP_FIN_WAIT_1 4
#define	UIP_FIN_WAIT_2 5
#define	UIP_CLOSING 6
#define	UIP_TIME_WAIT 7
#define	UIP_LAST_ACK 8
#define	UIP_TS_MASK 15
#define	UIP_STOPPED 16
#define	UIP_APPDATA_SIZE
#define	UIP_PROTO_ICMP 1
#define	UIP_PROTO_TCP 6
#define	UIP_PROTO_UDP 17
#define	UIP_PROTO_ICMP6 58
#define	UIP_IPH_LEN 20
#define	UIP_UDPH_LEN 8
#define	UIP_TCPH_LEN 20
#define	UIP_IPUDPH_LEN (UIP_UDPH_LEN + UIP_IPH_LEN)
#define	UIP_IPTCPH_LEN (UIP_TCPH_LEN + UIP_IPH_LEN)
#define	UIP_TCPIP_HLEN UIP_IPTCPH_LEN
Typedefs
typedef u16_t	uip_ip4addr_t [2]
typedef u16_t	uip_ip6addr_t [8]
typedef uip_ip4addr_t	uip_ipaddr_t
Functions
void	uip_setipid (u16_t id)
void	uip_add32 (u8_t *op32, u16_t op16)
u16_t	uip_chksum (u16_t *data, u16_t len)
u16_t	uip_ipchksum (void)
u16_t	uip_tcpchksum (void)
void	uip_init (void)
void	uip_unlisten (u16_t port)
void	uip_listen (u16_t port)
void	uip_process (u8_t flag)
u16_t	htons (u16_t val)
void	uip_send (const void *data, int len)
u16_t	uip_udpchksum (void)
Variables
uip_ipaddr_t	uip_hostaddr
uip_ipaddr_t	uip_draddr
uip_ipaddr_t	uip_netmask
struct uip_eth_addr	uip_ethaddr = {{0,0,0,0,0,0}}
u8_t	uip_buf [UIP_BUFSIZE+2]
void *	uip_appdata
void *	uip_sappdata
u16_t	uip_len
u16_t	uip_slen
u8_t	uip_flags
struct uip_conn *	uip_conn
struct uip_conn	uip_conns [UIP_CONNS]
u16_t	uip_listenports [UIP_LISTENPORTS]
u8_t	uip_acc32 [4]
void *	uip_appdata
struct uip_conn *	uip_conn
struct uip_conn	uip_conns [UIP_CONNS]
struct uip_stats	uip_stat
u8_t	uip_flags
uip_ipaddr_t	uip_hostaddr
uip_ipaddr_t	uip_netmask
uip_ipaddr_t	uip_draddr

Detailed Description

uIP is an implementation of the TCP/IP protocol stack intended for small 8-bit and 16-bit microcontrollers.

uIP provides the necessary protocols for Internet communication, with a very small code footprint and RAM requirements - the uIP code size is on the order of a few kilobytes and RAM usage is on the order of a few hundred bytes.

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Define Documentation

#define BUF ((struct uip_tcpip_hdr *)&uip_buf[UIP_LLH_LEN])

#define FBUF ((struct uip_tcpip_hdr *)&uip_reassbuf[0])

#define ICMP6_ECHO 128

#define ICMP6_ECHO_REPLY 129

#define ICMP6_FLAG_S (1 << 6)

#define ICMP6_NEIGHBOR_ADVERTISEMENT 136

#define ICMP6_NEIGHBOR_SOLICITATION 135

#define ICMP6_OPTION_SOURCE_LINK_ADDRESS 1

#define ICMP6_OPTION_TARGET_LINK_ADDRESS 2

#define ICMP_ECHO 8

#define ICMP_ECHO_REPLY 0

#define ICMPBUF ((struct uip_icmpip_hdr *)&uip_buf[UIP_LLH_LEN])

#define TCP_ACK 0x10

#define TCP_CTL 0x3f

#define TCP_FIN 0x01

#define TCP_OPT_END 0

#define TCP_OPT_MSS 2

#define TCP_OPT_MSS_LEN 4

#define TCP_OPT_NOOP 1

#define TCP_PSH 0x08

#define TCP_RST 0x04

#define TCP_SYN 0x02

#define TCP_URG 0x20

#define UDPBUF ((struct uip_udpip_hdr *)&uip_buf[UIP_LLH_LEN])

#define UIP_ABORT 32

#define UIP_ACKDATA 1

#define UIP_APPDATA_SIZE

The buffer size available for user data in the uip_buf buffer.

This macro holds the available size for user data in the uip_buf buffer. The macro is intended to be used for checking bounds of available user data.

Example:

 snprintf(uip_appdata, UIP_APPDATA_SIZE, "%u\n", i);

#define UIP_CLOSE 16

#define UIP_CLOSED 0

#define UIP_CLOSING 6

#define UIP_CONNECTED 64

#define UIP_DATA 1

#define UIP_ESTABLISHED 3

#define UIP_FIN_WAIT_1 4

#define UIP_FIN_WAIT_2 5

#define UIP_IPH_LEN 20

#define UIP_IPTCPH_LEN (UIP_TCPH_LEN + UIP_IPH_LEN)

#define UIP_IPUDPH_LEN (UIP_UDPH_LEN + UIP_IPH_LEN)

#define UIP_LAST_ACK 8

#define UIP_LOG ( m )

#define UIP_NEWDATA 2

#define UIP_POLL 8

#define UIP_POLL_REQUEST 3

#define UIP_PROTO_ICMP 1

#define UIP_PROTO_ICMP6 58

#define UIP_PROTO_TCP 6

#define UIP_PROTO_UDP 17

#define UIP_REXMIT 4

#define UIP_STAT ( s )

#define UIP_STOPPED 16

#define UIP_SYN_RCVD 1

#define UIP_SYN_SENT 2

#define UIP_TCPH_LEN 20

#define UIP_TCPIP_HLEN UIP_IPTCPH_LEN

#define UIP_TIME_WAIT 7

#define UIP_TIMEDOUT 128

#define UIP_TIMER 2

#define UIP_TS_MASK 15

#define UIP_UDP_SEND_CONN 4

#define UIP_UDPH_LEN 8

Typedef Documentation

typedef u16_t uip_ip4addr_t[2]

Repressentation of an IP address.

typedef u16_t uip_ip6addr_t[8]

typedef uip_ip4addr_t uip_ipaddr_t

Function Documentation

u16_t htons ( u16_t val )

Convert 16-bit quantity from host byte order to network byte order.

This function is primarily used for converting variables from host byte order to network byte order. For converting constants to network byte order, use the HTONS() macro instead.

void uip_add32	(	u8_t *	op32,
		u16_t	op16
	)

Carry out a 32-bit addition.

Because not all architectures for which uIP is intended has native 32-bit arithmetic, uIP uses an external C function for doing the required 32-bit additions in the TCP protocol processing. This function should add the two arguments and place the result in the global variable uip_acc32.

Note:: The 32-bit integer pointed to by the op32 parameter and the result in the uip_acc32 variable are in network byte order (big endian).

Parameters:

	op32	A pointer to a 4-byte array representing a 32-bit integer in network byte order (big endian).
	op16	A 16-bit integer in host byte order.

u16_t uip_chksum	(	u16_t *	buf,
		u16_t	len
	)

Calculate the Internet checksum over a buffer.

The Internet checksum is the one's complement of the one's complement sum of all 16-bit words in the buffer.

See RFC1071.

Parameters:

	buf	A pointer to the buffer over which the checksum is to be computed.
	len	The length of the buffer over which the checksum is to be computed.

Returns:: The Internet checksum of the buffer.

void uip_init ( void )

uIP initialization function.

This function should be called at boot up to initilize the uIP TCP/IP stack.

u16_t uip_ipchksum ( void )

Calculate the IP header checksum of the packet header in uip_buf.

The IP header checksum is the Internet checksum of the 20 bytes of the IP header.

Returns:: The IP header checksum of the IP header in the uip_buf buffer.

void uip_listen ( u16_t port )

Start listening to the specified port.

Note:: Since this function expects the port number in network byte order, a conversion using HTONS() or htons() is necessary.

 uip_listen(HTONS(80));

Parameters:

port

A 16-bit port number in network byte order.

void uip_process ( u8_t flag )

void uip_send	(	const void *	data,
		int	len
	)

Send data on the current connection.

This function is used to send out a single segment of TCP data. Only applications that have been invoked by uIP for event processing can send data.

The amount of data that actually is sent out after a call to this funcion is determined by the maximum amount of data TCP allows. uIP will automatically crop the data so that only the appropriate amount of data is sent. The function uip_mss() can be used to query uIP for the amount of data that actually will be sent.

Note:: This function does not guarantee that the sent data will arrive at the destination. If the data is lost in the network, the application will be invoked with the uip_rexmit() event being set. The application will then have to resend the data using this function.

Parameters:

	data	A pointer to the data which is to be sent.
	len	The maximum amount of data bytes to be sent.

void uip_setipid ( u16_t id )

uIP initialization function.

This function may be used at boot time to set the initial ip_id.

u16_t uip_tcpchksum ( void )

Calculate the TCP checksum of the packet in uip_buf and uip_appdata.

The TCP checksum is the Internet checksum of data contents of the TCP segment, and a pseudo-header as defined in RFC793.

Returns:: The TCP checksum of the TCP segment in uip_buf and pointed to by uip_appdata.

u16_t uip_udpchksum ( void )

Calculate the UDP checksum of the packet in uip_buf and uip_appdata.

The UDP checksum is the Internet checksum of data contents of the UDP segment, and a pseudo-header as defined in RFC768.

Returns:: The UDP checksum of the UDP segment in uip_buf and pointed to by uip_appdata.

void uip_unlisten ( u16_t port )

Stop listening to the specified port.

Note:: Since this function expects the port number in network byte order, a conversion using HTONS() or htons() is necessary.

 uip_unlisten(HTONS(80));

Parameters:

port

A 16-bit port number in network byte order.

Variable Documentation

u8_t uip_acc32[4]

4-byte array used for the 32-bit sequence number calculations.

void* uip_appdata

Pointer to the application data in the packet buffer.

This pointer points to the application data when the application is called. If the application wishes to send data, the application may use this space to write the data into before calling uip_send().

void* uip_appdata

Pointer to the application data in the packet buffer.

This pointer points to the application data when the application is called. If the application wishes to send data, the application may use this space to write the data into before calling uip_send().

u8_t uip_buf[UIP_BUFSIZE+2]

The uIP packet buffer.

The uip_buf array is used to hold incoming and outgoing packets. The device driver should place incoming data into this buffer. When sending data, the device driver should read the link level headers and the TCP/IP headers from this buffer. The size of the link level headers is configured by the UIP_LLH_LEN define.

Note:

The application data need not be placed in this buffer, so the device driver must read it from the place pointed to by the uip_appdata pointer as illustrated by the following example:

 void
 devicedriver_send(void)
 {
    hwsend(&uip_buf[0], UIP_LLH_LEN);
    if(uip_len <= UIP_LLH_LEN + UIP_TCPIP_HLEN) {
      hwsend(&uip_buf[UIP_LLH_LEN], uip_len - UIP_LLH_LEN);
    } else {
      hwsend(&uip_buf[UIP_LLH_LEN], UIP_TCPIP_HLEN);
      hwsend(uip_appdata, uip_len - UIP_TCPIP_HLEN - UIP_LLH_LEN);
    }
 }