diff options
Diffstat (limited to 'gpxe/src/include/gpxe/tcp.h')
| -rw-r--r-- | gpxe/src/include/gpxe/tcp.h | 318 |
1 files changed, 0 insertions, 318 deletions
diff --git a/gpxe/src/include/gpxe/tcp.h b/gpxe/src/include/gpxe/tcp.h deleted file mode 100644 index 9dc39fcc..00000000 --- a/gpxe/src/include/gpxe/tcp.h +++ /dev/null @@ -1,318 +0,0 @@ -#ifndef _GPXE_TCP_H -#define _GPXE_TCP_H - -/** @file - * - * TCP protocol - * - * This file defines the gPXE TCP API. - * - */ - -FILE_LICENCE ( GPL2_OR_LATER ); - -#include <gpxe/tcpip.h> - -/** - * A TCP header - */ -struct tcp_header { - uint16_t src; /* Source port */ - uint16_t dest; /* Destination port */ - uint32_t seq; /* Sequence number */ - uint32_t ack; /* Acknowledgement number */ - uint8_t hlen; /* Header length (4), Reserved (4) */ - uint8_t flags; /* Reserved (2), Flags (6) */ - uint16_t win; /* Advertised window */ - uint16_t csum; /* Checksum */ - uint16_t urg; /* Urgent pointer */ -}; - -/** @defgroup tcpopts TCP options - * @{ - */ - -/** End of TCP options list */ -#define TCP_OPTION_END 0 - -/** TCP option pad */ -#define TCP_OPTION_NOP 1 - -/** Generic TCP option */ -struct tcp_option { - uint8_t kind; - uint8_t length; -} __attribute__ (( packed )); - -/** TCP MSS option */ -struct tcp_mss_option { - uint8_t kind; - uint8_t length; - uint16_t mss; -} __attribute__ (( packed )); - -/** Code for the TCP MSS option */ -#define TCP_OPTION_MSS 2 - -/** TCP timestamp option */ -struct tcp_timestamp_option { - uint8_t kind; - uint8_t length; - uint32_t tsval; - uint32_t tsecr; -} __attribute__ (( packed )); - -/** Padded TCP timestamp option (used for sending) */ -struct tcp_timestamp_padded_option { - uint8_t nop[2]; - struct tcp_timestamp_option tsopt; -} __attribute__ (( packed )); - -/** Code for the TCP timestamp option */ -#define TCP_OPTION_TS 8 - -/** Parsed TCP options */ -struct tcp_options { - /** MSS option, if present */ - const struct tcp_mss_option *mssopt; - /** Timestampe option, if present */ - const struct tcp_timestamp_option *tsopt; -}; - -/** @} */ - -/* - * TCP flags - */ -#define TCP_CWR 0x80 -#define TCP_ECE 0x40 -#define TCP_URG 0x20 -#define TCP_ACK 0x10 -#define TCP_PSH 0x08 -#define TCP_RST 0x04 -#define TCP_SYN 0x02 -#define TCP_FIN 0x01 - -/** -* @defgroup tcpstates TCP states -* -* The TCP state is defined by a combination of the flags that have -* been sent to the peer, the flags that have been acknowledged by the -* peer, and the flags that have been received from the peer. -* -* @{ -*/ - -/** TCP flags that have been sent in outgoing packets */ -#define TCP_STATE_SENT(flags) ( (flags) << 0 ) -#define TCP_FLAGS_SENT(state) ( ( (state) >> 0 ) & 0xff ) - -/** TCP flags that have been acknowledged by the peer - * - * Note that this applies only to SYN and FIN. - */ -#define TCP_STATE_ACKED(flags) ( (flags) << 8 ) -#define TCP_FLAGS_ACKED(state) ( ( (state) >> 8 ) & 0xff ) - -/** TCP flags that have been received from the peer - * - * Note that this applies only to SYN and FIN, and that once SYN has - * been received, we should always be sending ACK. - */ -#define TCP_STATE_RCVD(flags) ( (flags) << 16 ) -#define TCP_FLAGS_RCVD(state) ( ( (state) >> 16 ) & 0xff ) - -/** TCP flags that are currently being sent in outgoing packets */ -#define TCP_FLAGS_SENDING(state) \ - ( TCP_FLAGS_SENT ( state ) & ~TCP_FLAGS_ACKED ( state ) ) - -/** CLOSED - * - * The connection has not yet been used for anything. - */ -#define TCP_CLOSED TCP_RST - -/** LISTEN - * - * Not currently used as a state; we have no support for listening - * connections. Given a unique value to avoid compiler warnings. - */ -#define TCP_LISTEN 0 - -/** SYN_SENT - * - * SYN has been sent, nothing has yet been received or acknowledged. - */ -#define TCP_SYN_SENT ( TCP_STATE_SENT ( TCP_SYN ) ) - -/** SYN_RCVD - * - * SYN has been sent but not acknowledged, SYN has been received. - */ -#define TCP_SYN_RCVD ( TCP_STATE_SENT ( TCP_SYN | TCP_ACK ) | \ - TCP_STATE_RCVD ( TCP_SYN ) ) - -/** ESTABLISHED - * - * SYN has been sent and acknowledged, SYN has been received. - */ -#define TCP_ESTABLISHED ( TCP_STATE_SENT ( TCP_SYN | TCP_ACK ) | \ - TCP_STATE_ACKED ( TCP_SYN ) | \ - TCP_STATE_RCVD ( TCP_SYN ) ) - -/** FIN_WAIT_1 - * - * SYN has been sent and acknowledged, SYN has been received, FIN has - * been sent but not acknowledged, FIN has not been received. - * - * RFC 793 shows that we can enter FIN_WAIT_1 without have had SYN - * acknowledged, i.e. if the application closes the connection after - * sending and receiving SYN, but before having had SYN acknowledged. - * However, we have to *pretend* that SYN has been acknowledged - * anyway, otherwise we end up sending SYN and FIN in the same - * sequence number slot. Therefore, when we transition from SYN_RCVD - * to FIN_WAIT_1, we have to remember to set TCP_STATE_ACKED(TCP_SYN) - * and increment our sequence number. - */ -#define TCP_FIN_WAIT_1 ( TCP_STATE_SENT ( TCP_SYN | TCP_ACK | TCP_FIN ) | \ - TCP_STATE_ACKED ( TCP_SYN ) | \ - TCP_STATE_RCVD ( TCP_SYN ) ) - -/** FIN_WAIT_2 - * - * SYN has been sent and acknowledged, SYN has been received, FIN has - * been sent and acknowledged, FIN ha not been received. - */ -#define TCP_FIN_WAIT_2 ( TCP_STATE_SENT ( TCP_SYN | TCP_ACK | TCP_FIN ) | \ - TCP_STATE_ACKED ( TCP_SYN | TCP_FIN ) | \ - TCP_STATE_RCVD ( TCP_SYN ) ) - -/** CLOSING / LAST_ACK - * - * SYN has been sent and acknowledged, SYN has been received, FIN has - * been sent but not acknowledged, FIN has been received. - * - * This state actually encompasses both CLOSING and LAST_ACK; they are - * identical with the definition of state that we use. I don't - * *believe* that they need to be distinguished. - */ -#define TCP_CLOSING_OR_LAST_ACK \ - ( TCP_STATE_SENT ( TCP_SYN | TCP_ACK | TCP_FIN ) | \ - TCP_STATE_ACKED ( TCP_SYN ) | \ - TCP_STATE_RCVD ( TCP_SYN | TCP_FIN ) ) - -/** TIME_WAIT - * - * SYN has been sent and acknowledged, SYN has been received, FIN has - * been sent and acknowledged, FIN has been received. - */ -#define TCP_TIME_WAIT ( TCP_STATE_SENT ( TCP_SYN | TCP_ACK | TCP_FIN ) | \ - TCP_STATE_ACKED ( TCP_SYN | TCP_FIN ) | \ - TCP_STATE_RCVD ( TCP_SYN | TCP_FIN ) ) - -/** CLOSE_WAIT - * - * SYN has been sent and acknowledged, SYN has been received, FIN has - * been received. - */ -#define TCP_CLOSE_WAIT ( TCP_STATE_SENT ( TCP_SYN | TCP_ACK ) | \ - TCP_STATE_ACKED ( TCP_SYN ) | \ - TCP_STATE_RCVD ( TCP_SYN | TCP_FIN ) ) - -/** Can send data in current state - * - * We can send data if and only if we have had our SYN acked and we - * have not yet sent our FIN. - */ -#define TCP_CAN_SEND_DATA(state) \ - ( ( (state) & ( TCP_STATE_ACKED ( TCP_SYN ) | \ - TCP_STATE_SENT ( TCP_FIN ) ) ) \ - == TCP_STATE_ACKED ( TCP_SYN ) ) - -/** Have ever been fully established - * - * We have been fully established if we have both received a SYN and - * had our own SYN acked. - */ -#define TCP_HAS_BEEN_ESTABLISHED(state) \ - ( ( (state) & ( TCP_STATE_ACKED ( TCP_SYN ) | \ - TCP_STATE_RCVD ( TCP_SYN ) ) ) \ - == ( TCP_STATE_ACKED ( TCP_SYN ) | TCP_STATE_RCVD ( TCP_SYN ) ) ) - -/** Have closed gracefully - * - * We have closed gracefully if we have both received a FIN and had - * our own FIN acked. - */ -#define TCP_CLOSED_GRACEFULLY(state) \ - ( ( (state) & ( TCP_STATE_ACKED ( TCP_FIN ) | \ - TCP_STATE_RCVD ( TCP_FIN ) ) ) \ - == ( TCP_STATE_ACKED ( TCP_FIN ) | TCP_STATE_RCVD ( TCP_FIN ) ) ) - -/** @} */ - -/** Mask for TCP header length field */ -#define TCP_MASK_HLEN 0xf0 - -/** Smallest port number on which a TCP connection can listen */ -#define TCP_MIN_PORT 1 - -/* Some IOB constants */ -#define MAX_HDR_LEN 100 -#define MAX_IOB_LEN 1500 -#define MIN_IOB_LEN MAX_HDR_LEN + 100 /* To account for padding by LL */ - -/** - * Maxmimum advertised TCP window size - * - * We estimate the TCP window size as the amount of free memory we - * have. This is not strictly accurate (since it ignores any space - * already allocated as RX buffers), but it will do for now. - * - * Since we don't store out-of-order received packets, the - * retransmission penalty is that the whole window contents must be - * resent. This suggests keeping the window size small, but bear in - * mind that the maximum bandwidth on any link is limited to - * - * max_bandwidth = ( tcp_window / round_trip_time ) - * - * With a 48kB window, which probably accurately reflects our amount - * of free memory, and a WAN RTT of say 200ms, this gives a maximum - * bandwidth of 240kB/s. This is sufficiently close to realistic that - * we will need to be careful that our advertised window doesn't end - * up limiting WAN download speeds. - * - * Finally, since the window goes into a 16-bit field and we cannot - * actually use 65536, we use a window size of (65536-4) to ensure - * that payloads remain dword-aligned. - */ -#define TCP_MAX_WINDOW_SIZE ( 65536 - 4 ) -//#define TCP_MAX_WINDOW_SIZE 4096 - -/** - * Path MTU - * - * We really ought to implement Path MTU discovery. Until we do, - * anything with a path MTU greater than this may fail. - */ -#define TCP_PATH_MTU 1460 - -/** - * Advertised TCP MSS - * - * We currently hardcode this to a reasonable value and hope that the - * sender uses path MTU discovery. The alternative is breaking the - * abstraction layer so that we can find out the MTU from the IP layer - * (which would have to find out from the net device layer). - */ -#define TCP_MSS 1460 - -/** TCP maximum segment lifetime - * - * Currently set to 2 minutes, as per RFC 793. - */ -#define TCP_MSL ( 2 * 60 * TICKS_PER_SEC ) - -extern struct tcpip_protocol tcp_protocol; - -#endif /* _GPXE_TCP_H */ |