/****************************************************************************
* include/nuttx/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, 2009-2010, 2012-2014 Gregory Nutt. All rights
* reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 __INCLUDE_NUTTX_NET_UIP_UIP_TCP_H
#define __INCLUDE_NUTTX_NET_UIP_UIP_TCP_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#ifdef CONFIG_NET_TCP
#include <stdint.h>
#include <stdbool.h>
#include <nuttx/net/netconfig.h>
#include <nuttx/net/uip/uip.h>
/****************************************************************************
* Pre-processor 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_TS_MASK 0x0f /* Bits 0-3: TCP state */
#define UIP_CLOSED 0x00 /* The connection is not in use and available */
#define UIP_ALLOCATED 0x01 /* The connection is allocated, but not yet initialized */
#define UIP_SYN_RCVD 0x02
#define UIP_SYN_SENT 0x03
#define UIP_ESTABLISHED 0x04
#define UIP_FIN_WAIT_1 0x05
#define UIP_FIN_WAIT_2 0x06
#define UIP_CLOSING 0x07
#define UIP_TIME_WAIT 0x08
#define UIP_LAST_ACK 0x09
#define UIP_STOPPED 0x10 /* Bit 4: stopped */
/* Bit 5-7: Unused, but not available */
/* 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
/* Initial minimum MSS according to RFC 879
*
* There have been some assumptions made about using other than the
* default size for datagrams with some unfortunate results.
*
* HOSTS MUST NOT SEND DATAGRAMS LARGER THAN 576 OCTETS UNLESS THEY
* HAVE SPECIFIC KNOWLEDGE THAT THE DESTINATION HOST IS PREPARED TO
* ACCEPT LARGER DATAGRAMS.
*
* This is a long established rule.
*/
#if UIP_TCP_MSS > 576
# define UIP_TCP_INITIAL_MSS 576
#else
# define UIP_TCP_INITIAL_MSS UIP_TCP_MSS
#endif
#ifdef CONFIG_NET_TCP_WRITE_BUFFERS
/* TCP write buffer access macros */
# define WRB_SEQNO(wrb) ((wrb)->wb_seqno)
# define WRB_PKTLEN(wrb) ((wrb)->wb_iob->io_pktlen)
# define WRB_SENT(wrb) ((wrb)->wb_sent)
# define WRB_NRTX(wrb) ((wrb)->wb_nrtx)
# define WRB_IOB(wrb) ((wrb)->wb_iob)
# define WRB_COPYOUT(wrb,dest,n) (iob_copyout(dest,(wrb)->wb_iob,(n),0))
# define WRB_COPYIN(wrb,src,n) (iob_copyin((wrb)->wb_iob,src,(n),0))
# define WRB_TRIM(wrb,n) \
do { (wrb)->wb_iob = iob_trimhead((wrb)->wb_iob,(n)); } while (0)
#ifdef CONFIG_DEBUG
# define WRB_DUMP(msg,wrb,len,offset) \
tcp_wrbuffer_dump(msg,wrb,len,offset)
#else
# define WRB_DUMP(msg,wrb,len,offset)
#endif
#endif
/****************************************************************************
* 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' fields whose 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_backlog_s; /* Forward reference */
struct uip_conn
{
dq_entry_t node; /* Implements a doubly linked list */
uip_ipaddr_t ripaddr; /* The IP address of the remote host */
uint8_t rcvseq[4]; /* The sequence number that we expect to
* receive next */
uint8_t sndseq[4]; /* The sequence number that was last sent by us */
uint8_t crefs; /* Reference counts on this instance */
uint8_t sa; /* Retransmission time-out calculation state
* variable */
uint8_t sv; /* Retransmission time-out calculation state
* variable */
uint8_t rto; /* Retransmission time-out */
uint8_t tcpstateflags; /* TCP state and flags */
uint8_t timer; /* The retransmission timer (units: half-seconds) */
uint8_t nrtx; /* The number of retransmissions for the last
* segment sent */
uint16_t lport; /* The local TCP port, in network byte order */
uint16_t rport; /* The remoteTCP port, in network byte order */
uint16_t mss; /* Current maximum segment size for the
* connection */
uint16_t winsize; /* Current window size of the connection */
#ifdef CONFIG_NET_TCP_WRITE_BUFFERS
uint32_t unacked; /* Number bytes sent but not yet ACKed */
#else
uint16_t unacked; /* Number bytes sent but not yet ACKed */
#endif
/* Read-ahead buffering.
*
* readahead - A singly linked list of type struct uip_readahead_s
* where the TCP/IP read-ahead data is retained.
*/
#ifdef CONFIG_NET_TCP_READAHEAD
sq_queue_t readahead; /* Read-ahead buffering */
#endif
/* Write buffering
*
* write_q - The queue of unsent I/O buffers. The head of this
* list may be partially sent. FIFO ordering.
* unacked_q - A queue of completely sent, but unacked I/O buffer
* chains. Sequence number ordering.
*/
#ifdef CONFIG_NET_TCP_WRITE_BUFFERS
sq_queue_t write_q; /* Write buffering for segments */
sq_queue_t unacked_q; /* Write buffering for un-ACKed segments */
uint16_t expired; /* Number segments retransmitted but not yet ACKed,
* it can only be updated at UIP_ESTABLISHED state */
uint16_t sent; /* The number of bytes sent (ACKed and un-ACKed) */
uint32_t isn; /* Initial sequence number */
#endif
/* Listen backlog support
*
* blparent - The backlog parent. If this connection is backlogged,
* this field will be non-null and will refer to the TCP connection
* structure in which this connection is backlogged.
* backlog - The pending connection backlog. If this connection is
* configured as a listener with backlog, then this refers to the
* struct uip_backlog_s tear-off structure that manages that backlog.
*/
#ifdef CONFIG_NET_TCPBACKLOG
FAR struct uip_conn *blparent;
FAR struct uip_backlog_s *backlog;
#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).
*/
FAR struct uip_callback_s *list;
/* accept() is called when the TCP logic has created a connection */
FAR void *accept_private;
int (*accept)(FAR struct uip_conn *listener, struct uip_conn *conn);
/* connection_event() is called on any of the subset of connection-related
* events.
*/
FAR void *connection_private;
void (*connection_event)(FAR struct uip_conn *conn, uint16_t 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.
*/
#ifdef CONFIG_NET_TCP_READAHEAD
struct uip_readahead_s
{
sq_entry_t rh_node; /* Supports a singly linked list */
uint16_t rh_nbytes; /* Number of bytes available in this buffer */
uint8_t rh_buffer[CONFIG_NET_TCP_READAHEAD_BUFSIZE];
};
#endif
/* This structure supports TCP write buffering */
#ifdef CONFIG_NET_TCP_WRITE_BUFFERS
struct iob_s; /* Forward reference */
struct tcp_wrbuffer_s
{
sq_entry_t wb_node; /* Supports a singly linked list */
uint32_t wb_seqno; /* Sequence number of the write segment */
uint16_t wb_sent; /* Number of bytes sent from the I/O buffer chain */
uint8_t wb_nrtx; /* The number of retransmissions for the last
* segment sent */
struct iob_s *wb_iob; /* Head of the I/O buffer chain */
};
#endif
/* Support for listen backlog:
*
* struct uip_blcontainer_s describes one backlogged connection
* struct uip_backlog_s is a "tear-off" describing all backlog for a
* listener connection
*/
#ifdef CONFIG_NET_TCPBACKLOG
struct uip_blcontainer_s
{
sq_entry_t bc_node; /* Implements a singly linked list */
FAR struct uip_conn *bc_conn; /* Holds reference to the new connection structure */
};
struct uip_backlog_s
{
sq_queue_t bl_free; /* Implements a singly-linked list of free containers */
sq_queue_t bl_pending; /* Implements a singly-linked list of pending connections */
};
#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_t vtc; /* Bits 0-3: version, bits 4-7: traffic class (MS) */
uint8_t tcf; /* Bits 0-3: traffic class (LS), 4-bits: flow label (MS) */
uint16_t flow; /* 16-bit flow label (LS) */
uint8_t len[2]; /* 16-bit Payload length */
uint8_t proto; /* 8-bit Next header (same as IPv4 protocol field) */
uint8_t 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_t vhl; /* 8-bit Version (4) and header length (5 or 6) */
uint8_t tos; /* 8-bit Type of service (e.g., 6=TCP) */
uint8_t len[2]; /* 16-bit Total length */
uint8_t ipid[2]; /* 16-bit Identification */
uint8_t ipoffset[2]; /* 16-bit IP flags + fragment offset */
uint8_t ttl; /* 8-bit Time to Live */
uint8_t proto; /* 8-bit Protocol */
uint16_t ipchksum; /* 16-bit Header checksum */
uint16_t srcipaddr[2]; /* 32-bit Source IP address */
uint16_t destipaddr[2]; /* 32-bit Destination IP address */
#endif /* CONFIG_NET_IPv6 */
/* TCP header */
uint16_t srcport;
uint16_t destport;
uint8_t seqno[4];
uint8_t ackno[4];
uint8_t tcpoffset;
uint8_t flags;
uint8_t wnd[2];
uint16_t tcpchksum;
uint8_t urgp[2];
uint8_t 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
*/
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()
*/
void uip_tcpfree(struct uip_conn *conn);
/* Bind a TCP connection to a local address */
#ifdef CONFIG_NET_IPv6
int uip_tcpbind(struct uip_conn *conn, const struct sockaddr_in6 *addr);
#else
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
int uip_tcpconnect(struct uip_conn *conn, const struct sockaddr_in6 *addr);
#else
int uip_tcpconnect(struct uip_conn *conn, const struct sockaddr_in *addr);
#endif
/* Start listening to the port bound to the specified TCP connection */
int uip_listen(struct uip_conn *conn);
/* Stop listening to the port bound to the specified TCP connection */
int uip_unlisten(struct uip_conn *conn);
/* Access to TCP read-ahead buffers */
#ifdef CONFIG_NET_TCP_READAHEAD
FAR struct uip_readahead_s *uip_tcpreadahead_alloc(void);
void uip_tcpreadahead_release(FAR struct uip_readahead_s *readahead);
#endif /* CONFIG_NET_TCP_READAHEAD */
/* Backlog support */
#ifdef CONFIG_NET_TCPBACKLOG
/* APIs to create and terminate TCP backlog support */
int uip_backlogcreate(FAR struct uip_conn *conn, int nblg);
int uip_backlogdestroy(FAR struct uip_conn *conn);
/* APIs to manage individual backlog actions */
int uip_backlogadd(FAR struct uip_conn *conn, FAR struct uip_conn *blconn);
#ifndef CONFIG_DISABLE_POLL
bool uip_backlogavailable(FAR struct uip_conn *conn);
#else
# define uip_backlogavailable(conn) (false);
#endif
FAR struct uip_conn *uip_backlogremove(FAR struct uip_conn *conn);
int uip_backlogdelete(FAR struct uip_conn *conn, FAR struct uip_conn *blconn);
#else
# define uip_backlogcreate(conn,nblg) (-ENOSYS)
# define uip_backlogdestroy(conn) (-ENOSYS)
# define uip_backlogadd(conn,blconn) (-ENOSYS)
# define uip_backlogavailable(conn) (false);
# define uip_backlogremove(conn) (NULL)
#endif
/* 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 current maximum segment size that can be sent on the current
* connection.
*/
#define uip_mss(conn) ((conn)->mss)
#endif /* CONFIG_NET_TCP */
#endif /* __INCLUDE_NUTTX_NET_UIP_UIP_TCP_H */
