/****************************************************************************
* net/uip/uip-tcp.h
* Header file for the uIP TCP/IP stack.
*
* The uIP TCP/IP stack header file contains definitions for a number
* of C macros that are used by uIP programs as well as internal uIP
* structures, TCP/IP header structures and function declarations.
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* This logic was leveraged from uIP which also has a BSD-style license:
*
* Author Adam Dunkels <adam@dunkels.com>
* Copyright (c) 2001-2003, Adam Dunkels.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __NET_UIP_UIP_TCP_H
#define __NET_UIP_UIP_TCP_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#ifdef CONFIG_NET_TCP
#include <sys/types.h>
#include <net/uip/uipopt.h>
/****************************************************************************
* Definitions
****************************************************************************/
/* TCP definitions */
#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 /* End of TCP options list */
#define TCP_OPT_NOOP 1 /* "No-operation" TCP option */
#define TCP_OPT_MSS 2 /* Maximum segment size TCP option */
#define TCP_OPT_MSS_LEN 4 /* Length of TCP MSS option. */
/* The TCP states used in the struct uip_conn tcpstateflags field */
#define UIP_CLOSED 0 /* The connection is not in use and available */
#define UIP_ALLOCATED 1 /* The connection is allocated, but not yet initialized */
#define UIP_SYN_RCVD 2
#define UIP_SYN_SENT 3
#define UIP_ESTABLISHED 4
#define UIP_FIN_WAIT_1 5
#define UIP_FIN_WAIT_2 6
#define UIP_CLOSING 7
#define UIP_TIME_WAIT 8
#define UIP_LAST_ACK 9
#define UIP_TS_MASK 15
#define UIP_STOPPED 16
/* Flag bits in 16-bit flags+ipoffset IPv4 TCP header field */
#define UIP_TCPFLAG_RESERVED 0x8000
#define UIP_TCPFLAG_DONTFRAG 0x4000
#define UIP_TCPFLAG_MOREFRAGS 0x2000
/* TCP header sizes */
#define UIP_TCPH_LEN 20 /* Size of TCP header */
#define UIP_IPTCPH_LEN (UIP_TCPH_LEN + UIP_IPH_LEN) /* Size of IP + TCP header */
#define UIP_TCPIP_HLEN UIP_IPTCPH_LEN
/****************************************************************************
* Public Type Definitions
****************************************************************************/
/* Representation of a uIP TCP connection.
*
* The uip_conn structure is used for identifying a connection. All
* but one field in the structure are to be considered read-only by an
* application. The only exception is the "private: field whos purpose
* is to let the application store application-specific state (e.g.,
* file pointers) for the connection.
*/
struct uip_driver_s; /* Forward reference */
struct uip_callback_s; /* Forward reference */
struct uip_conn
{
dq_entry_t node; /* Implements a doubly linked list */
#if 0 /* Not used */
uip_ipaddr_t lipaddr; /* The local IP address */
#endif
uip_ipaddr_t ripaddr; /* The IP address of the remote host */
uint16 lport; /* The local TCP port, in network byte order */
uint16 rport; /* The remoteTCP port, in network byte order */
uint8 rcv_nxt[4]; /* The sequence number that we expect to
* receive next */
uint8 snd_nxt[4]; /* The sequence number that was last sent by us */
uint16 len; /* Length of the data that was previously sent */
uint16 mss; /* Current maximum segment size for the
* connection */
uint16 initialmss; /* Initial maximum segment size for the
* connection */
uint8 sa; /* Retransmission time-out calculation state
* variable */
uint8 sv; /* Retransmission time-out calculation state
* variable */
uint8 rto; /* Retransmission time-out */
uint8 tcpstateflags; /* TCP state and flags */
uint8 timer; /* The retransmission timer (units: half-seconds) */
uint8 nrtx; /* The number of retransmissions for the last
* segment sent */
/* Read-ahead buffering */
#if CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
sq_queue_t readahead;
#endif
/* Application callbacks:
*
* Data transfer events are retained in 'list'. Event handlers in 'list'
* are called for events specified in the flags set within struct
* uip_callback_s
*
* When an callback is executed from 'list', the input flags are normally
* returned, however, the implementation may set one of the following:
*
* UIP_CLOSE - Gracefully close the current connection
* UIP_ABORT - Abort (reset) the current connection on an error that
* prevents UIP_CLOSE from working.
*
* And/Or set/clear the following:
*
* UIP_NEWDATA - May be cleared to indicate that the data was consumed
* and that no further process of the new data should be
* attempted.
* UIP_SNDACK - If UIP_NEWDATA is cleared, then UIP_SNDACK may be set
* to indicate that an ACK should be included in the response.
* (In UIP_NEWDATA is cleared bu UIP_SNDACK is not set, then
* dev->d_len should also be cleared).
*/
struct uip_callback_s *list;
/* accept() is called when the TCP logic has created a connection */
void *accept_private;
int (*accept)(struct uip_conn *listener, struct uip_conn *conn);
/* connection_event() is called on any of the subset of connection-related events */
void *connection_private;
void (*connection_event)(struct uip_conn *conn, uint16 flags);
};
/* The following structure is used to handle read-ahead buffering for TCP
* connection. When incoming TCP data is received while no application is
* listening for the data, that data will be retained in these read-ahead
* buffers so that no data is lost.
*/
#if CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
struct uip_readahead_s
{
sq_entry_t rh_node; /* Supports a singly linked list */
uint16 rh_nbytes; /* Number of bytes available in this buffer */
uint8 rh_buffer[CONFIG_NET_TCP_READAHEAD_BUFSIZE];
};
#endif
/* The structure holding the TCP/IP statistics that are gathered if
* CONFIG_NET_STATISTICS is defined.
*/
#ifdef CONFIG_NET_STATISTICS
struct uip_tcp_stats_s
{
uip_stats_t drop; /* Number of dropped TCP segments */
uip_stats_t recv; /* Number of received TCP segments */
uip_stats_t sent; /* Number of sent TCP segments */
uip_stats_t chkerr; /* Number of TCP segments with a bad checksum */
uip_stats_t ackerr; /* Number of TCP segments with a bad ACK number */
uip_stats_t rst; /* Number of received TCP RST (reset) segments */
uip_stats_t rexmit; /* Number of retransmitted TCP segments */
uip_stats_t syndrop; /* Number of dropped SYNs due to too few
available connections */
uip_stats_t synrst; /* Number of SYNs for closed ports triggering a RST */
};
#endif
/* The TCP and IP headers */
struct uip_tcpip_hdr
{
#ifdef CONFIG_NET_IPv6
/* IPv6 Ip header */
uint8 vtc; /* Bits 0-3: version, bits 4-7: traffic class (MS) */
uint8 tcf; /* Bits 0-3: traffic class (LS), 4-bits: flow label (MS) */
uint16 flow; /* 16-bit flow label (LS) */
uint8 len[2]; /* 16-bit Payload length */
uint8 proto; /* 8-bit Next header (same as IPv4 protocol field) */
uint8 ttl; /* 8-bit Hop limit (like IPv4 TTL field) */
uip_ip6addr_t srcipaddr; /* 128-bit Source address */
uip_ip6addr_t destipaddr; /* 128-bit Destination address */
#else /* CONFIG_NET_IPv6 */
/* IPv4 IP header */
uint8 vhl; /* 8-bit Version (4) and header length (5 or 6) */
uint8 tos; /* 8-bit Type of service (e.g., 6=TCP) */
uint8 len[2]; /* 16-bit Total length */
uint8 ipid[2]; /* 16-bit Identification */
uint8 ipoffset[2]; /* 16-bit IP flags + fragment offset */
uint8 ttl; /* 8-bit Time to Live */
uint8 proto; /* 8-bit Protocol */
uint16 ipchksum; /* 16-bit Header checksum */
uint16 srcipaddr[2]; /* 32-bit Source IP address */
uint16 destipaddr[2]; /* 32-bit Destination IP address */
#endif /* CONFIG_NET_IPv6 */
/* TCP header */
uint16 srcport;
uint16 destport;
uint8 seqno[4];
uint8 ackno[4];
uint8 tcpoffset;
uint8 flags;
uint8 wnd[2];
uint16 tcpchksum;
uint8 urgp[2];
uint8 optdata[4];
};
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/* uIP application functions
*
* Functions used by an application running of top of uIP. This includes
* functions for opening and closing connections, sending and receiving
* data, etc.
*
* Find a free connection structure and allocate it for use. This is
* normally something done by the implementation of the socket() API
*/
extern struct uip_conn *uip_tcpalloc(void);
/* Allocate a new TCP data callback */
#define uip_tcpcallbackalloc(conn) uip_callbackalloc(&conn->list)
#define uip_tcpcallbackfree(conn,cb) uip_callbackfree(cb, &conn->list)
/* Free a connection structure that is no longer in use. This should
* be done by the implementation of close()
*/
extern void uip_tcpfree(struct uip_conn *conn);
/* Bind a TCP connection to a local address */
#ifdef CONFIG_NET_IPv6
extern int uip_tcpbind(struct uip_conn *conn, const struct sockaddr_in6 *addr);
#else
extern int uip_tcpbind(struct uip_conn *conn, const struct sockaddr_in *addr);
#endif
/* This function implements the UIP specific parts of the standard
* TCP connect() operation: It connects to a remote host using TCP.
*
* This function is used to start a new connection to the specified
* port on the specied host. It uses the connection structure that was
* allocated by a preceding socket() call. It sets the connection to
* the SYN_SENT state and sets the retransmission timer to 0. This will
* cause a TCP SYN segment to be sent out the next time this connection
* is periodically processed, which usually is done within 0.5 seconds
* after the call to uip_tcpconnect().
*
* This function is called from normal user level code.
*/
#ifdef CONFIG_NET_IPv6
extern int uip_tcpconnect(struct uip_conn *conn, const struct sockaddr_in6 *addr);
#else
extern int uip_tcpconnect(struct uip_conn *conn, const struct sockaddr_in *addr);
#endif
/* Start listening to the port bound to the specified TCP connection */
extern int uip_listen(struct uip_conn *conn);
/* Stop listening to the port bound to the specified TCP connection */
extern int uip_unlisten(struct uip_conn *conn);
/* Check if a connection has outstanding (i.e., unacknowledged) data */
#define uip_outstanding(conn) ((conn)->len)
/* Access to TCP read-ahead buffers */
#if CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
extern struct uip_readahead_s *uip_tcpreadaheadalloc(void);
extern void uip_tcpreadaheadrelease(struct uip_readahead_s *buf);
#endif /* CONFIG_NET_NTCP_READAHEAD_BUFFERS */
/* Tell the sending host to stop sending data.
*
* This function will close our receiver's window so that we stop
* receiving data for the current connection.
*/
#define uip_stop(conn) ((conn)->tcpstateflags |= UIP_STOPPED)
/* Find out if the current connection has been previously stopped with
* uip_stop().
*/
#define uip_stopped(conn) ((conn)->tcpstateflags & UIP_STOPPED)
/* Restart the current connection, if is has previously been stopped
* with uip_stop().
*
* This function will open the receiver's window again so that we
* start receiving data for the current connection.
*/
#define uip_restart(conn,f) \
do { \
(f) |= UIP_NEWDATA; \
(conn)->tcpstateflags &= ~UIP_STOPPED; \
} while(0)
/* Get the initial maxium segment size (MSS) of the current
* connection.
*/
#define uip_initialmss(conn) ((conn)->initialmss)
/* Get the current maxium segment size that can be sent on the current
* connection.
*
* The current maxiumum segment size that can be sent on the
* connection is computed from the receiver's window and the MSS of
* the connection (which also is available by calling
* uip_initialmss()).
*/
#define uip_mss(conn) ((conn)->mss)
#endif /* CONFIG_NET_TCP */
#endif /* __NET_UIP_UIP_TCP_H */
