mirror of
https://github.com/AsahiLinux/u-boot
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721 lines
19 KiB
C
721 lines
19 KiB
C
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// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright 2017 Duncan Hare, all rights reserved.
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*/
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/*
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* General Desription:
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*
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* TCP support for the wget command, for fast file downloading.
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*
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* HTTP/TCP Receiver:
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*
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* Prerequisites: - own ethernet address
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* - own IP address
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* - Server IP address
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* - Server with TCP
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* - TCP application (eg wget)
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* Next Step HTTPS?
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*/
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#include <common.h>
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#include <command.h>
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#include <console.h>
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#include <env_internal.h>
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#include <errno.h>
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#include <net.h>
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#include <net/tcp.h>
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/*
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* TCP sliding window control used by us to request re-TX
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*/
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static struct tcp_sack_v tcp_lost;
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/* TCP option timestamp */
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static u32 loc_timestamp;
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static u32 rmt_timestamp;
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static u32 tcp_seq_init;
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static u32 tcp_ack_edge;
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static u32 tcp_seq_max;
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static int tcp_activity_count;
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/*
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* Search for TCP_SACK and review the comments before the code section
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* TCP_SACK is the number of packets at the front of the stream
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*/
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enum pkt_state {PKT, NOPKT};
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struct sack_r {
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struct sack_edges se;
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enum pkt_state st;
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};
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static struct sack_r edge_a[TCP_SACK];
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static unsigned int sack_idx;
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static unsigned int prev_len;
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/*
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* TCP lengths are stored as a rounded up number of 32 bit words.
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* Add 3 to length round up, rounded, then divided into the
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* length in 32 bit words.
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*/
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#define LEN_B_TO_DW(x) ((x) >> 2)
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#define ROUND_TCPHDR_LEN(x) (LEN_B_TO_DW((x) + 3))
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#define SHIFT_TO_TCPHDRLEN_FIELD(x) ((x) << 4)
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#define GET_TCP_HDR_LEN_IN_BYTES(x) ((x) >> 2)
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/* TCP connection state */
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static enum tcp_state current_tcp_state;
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/* Current TCP RX packet handler */
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static rxhand_tcp *tcp_packet_handler;
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/**
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* tcp_get_tcp_state() - get current TCP state
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*
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* Return: Current TCP state
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*/
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enum tcp_state tcp_get_tcp_state(void)
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{
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return current_tcp_state;
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}
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/**
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* tcp_set_tcp_state() - set current TCP state
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* @new_state: new TCP state
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*/
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void tcp_set_tcp_state(enum tcp_state new_state)
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{
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current_tcp_state = new_state;
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}
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static void dummy_handler(uchar *pkt, unsigned int dport,
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struct in_addr sip, unsigned int sport,
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unsigned int len)
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{
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}
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/**
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* tcp_set_tcp_handler() - set a handler to receive data
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* @f: handler
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*/
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void tcp_set_tcp_handler(rxhand_tcp *f)
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{
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debug_cond(DEBUG_INT_STATE, "--- net_loop TCP handler set (%p)\n", f);
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if (!f)
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tcp_packet_handler = dummy_handler;
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else
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tcp_packet_handler = f;
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}
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/**
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* tcp_set_pseudo_header() - set TCP pseudo header
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* @pkt: the packet
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* @src: source IP address
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* @dest: destinaion IP address
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* @tcp_len: tcp length
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* @pkt_len: packet length
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*
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* Return: the checksum of the packet
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*/
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u16 tcp_set_pseudo_header(uchar *pkt, struct in_addr src, struct in_addr dest,
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int tcp_len, int pkt_len)
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{
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union tcp_build_pkt *b = (union tcp_build_pkt *)pkt;
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int checksum_len;
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/*
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* Pseudo header
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*
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* Zero the byte after the last byte so that the header checksum
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* will always work.
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*/
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pkt[pkt_len] = 0;
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net_copy_ip((void *)&b->ph.p_src, &src);
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net_copy_ip((void *)&b->ph.p_dst, &dest);
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b->ph.rsvd = 0;
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b->ph.p = IPPROTO_TCP;
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b->ph.len = htons(tcp_len);
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checksum_len = tcp_len + PSEUDO_HDR_SIZE;
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debug_cond(DEBUG_DEV_PKT,
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"TCP Pesudo Header (to=%pI4, from=%pI4, Len=%d)\n",
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&b->ph.p_dst, &b->ph.p_src, checksum_len);
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return compute_ip_checksum(pkt + PSEUDO_PAD_SIZE, checksum_len);
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}
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/**
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* net_set_ack_options() - set TCP options in acknowledge packets
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* @b: the packet
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*
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* Return: TCP header length
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*/
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int net_set_ack_options(union tcp_build_pkt *b)
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{
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b->sack.hdr.tcp_hlen = SHIFT_TO_TCPHDRLEN_FIELD(LEN_B_TO_DW(TCP_HDR_SIZE));
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b->sack.t_opt.kind = TCP_O_TS;
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b->sack.t_opt.len = TCP_OPT_LEN_A;
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b->sack.t_opt.t_snd = htons(loc_timestamp);
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b->sack.t_opt.t_rcv = rmt_timestamp;
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b->sack.sack_v.kind = TCP_1_NOP;
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b->sack.sack_v.len = 0;
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if (IS_ENABLED(CONFIG_PROT_TCP_SACK)) {
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if (tcp_lost.len > TCP_OPT_LEN_2) {
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debug_cond(DEBUG_DEV_PKT, "TCP ack opt lost.len %x\n",
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tcp_lost.len);
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b->sack.sack_v.len = tcp_lost.len;
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b->sack.sack_v.kind = TCP_V_SACK;
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b->sack.sack_v.hill[0].l = htonl(tcp_lost.hill[0].l);
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b->sack.sack_v.hill[0].r = htonl(tcp_lost.hill[0].r);
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/*
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* These SACK structures are initialized with NOPs to
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* provide TCP header alignment padding. There are 4
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* SACK structures used for both header padding and
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* internally.
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*/
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b->sack.sack_v.hill[1].l = htonl(tcp_lost.hill[1].l);
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b->sack.sack_v.hill[1].r = htonl(tcp_lost.hill[1].r);
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b->sack.sack_v.hill[2].l = htonl(tcp_lost.hill[2].l);
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b->sack.sack_v.hill[2].r = htonl(tcp_lost.hill[2].r);
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b->sack.sack_v.hill[3].l = TCP_O_NOP;
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b->sack.sack_v.hill[3].r = TCP_O_NOP;
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}
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b->sack.hdr.tcp_hlen = SHIFT_TO_TCPHDRLEN_FIELD(ROUND_TCPHDR_LEN(TCP_HDR_SIZE +
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TCP_TSOPT_SIZE +
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tcp_lost.len));
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} else {
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b->sack.sack_v.kind = 0;
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b->sack.hdr.tcp_hlen = SHIFT_TO_TCPHDRLEN_FIELD(ROUND_TCPHDR_LEN(TCP_HDR_SIZE +
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TCP_TSOPT_SIZE));
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}
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/*
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* This returns the actual rounded up length of the
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* TCP header to add to the total packet length
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*/
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return GET_TCP_HDR_LEN_IN_BYTES(b->sack.hdr.tcp_hlen);
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}
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/**
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* net_set_ack_options() - set TCP options in SYN packets
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* @b: the packet
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*/
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void net_set_syn_options(union tcp_build_pkt *b)
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{
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if (IS_ENABLED(CONFIG_PROT_TCP_SACK))
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tcp_lost.len = 0;
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b->ip.hdr.tcp_hlen = 0xa0;
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b->ip.mss.kind = TCP_O_MSS;
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b->ip.mss.len = TCP_OPT_LEN_4;
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b->ip.mss.mss = htons(TCP_MSS);
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b->ip.scale.kind = TCP_O_SCL;
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b->ip.scale.scale = TCP_SCALE;
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b->ip.scale.len = TCP_OPT_LEN_3;
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if (IS_ENABLED(CONFIG_PROT_TCP_SACK)) {
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b->ip.sack_p.kind = TCP_P_SACK;
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b->ip.sack_p.len = TCP_OPT_LEN_2;
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} else {
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b->ip.sack_p.kind = TCP_1_NOP;
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b->ip.sack_p.len = TCP_1_NOP;
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}
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b->ip.t_opt.kind = TCP_O_TS;
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b->ip.t_opt.len = TCP_OPT_LEN_A;
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loc_timestamp = get_ticks();
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rmt_timestamp = 0;
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b->ip.t_opt.t_snd = 0;
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b->ip.t_opt.t_rcv = 0;
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b->ip.end = TCP_O_END;
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}
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int tcp_set_tcp_header(uchar *pkt, int dport, int sport, int payload_len,
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u8 action, u32 tcp_seq_num, u32 tcp_ack_num)
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{
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union tcp_build_pkt *b = (union tcp_build_pkt *)pkt;
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int pkt_hdr_len;
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int pkt_len;
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int tcp_len;
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/*
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* Header: 5 32 bit words. 4 bits TCP header Length,
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* 4 bits reserved options
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*/
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b->ip.hdr.tcp_flags = action;
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pkt_hdr_len = IP_TCP_HDR_SIZE;
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b->ip.hdr.tcp_hlen = SHIFT_TO_TCPHDRLEN_FIELD(LEN_B_TO_DW(TCP_HDR_SIZE));
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switch (action) {
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case TCP_SYN:
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debug_cond(DEBUG_DEV_PKT,
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"TCP Hdr:SYN (%pI4, %pI4, sq=%d, ak=%d)\n",
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&net_server_ip, &net_ip,
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tcp_seq_num, tcp_ack_num);
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tcp_activity_count = 0;
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net_set_syn_options(b);
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tcp_seq_num = 0;
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tcp_ack_num = 0;
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pkt_hdr_len = IP_TCP_O_SIZE;
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if (current_tcp_state == TCP_SYN_SENT) { /* Too many SYNs */
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action = TCP_FIN;
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current_tcp_state = TCP_FIN_WAIT_1;
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} else {
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current_tcp_state = TCP_SYN_SENT;
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}
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break;
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case TCP_ACK:
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pkt_hdr_len = IP_HDR_SIZE + net_set_ack_options(b);
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b->ip.hdr.tcp_flags = action;
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debug_cond(DEBUG_DEV_PKT,
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"TCP Hdr:ACK (%pI4, %pI4, s=%d, a=%d, A=%x)\n",
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&net_server_ip, &net_ip, tcp_seq_num, tcp_ack_num,
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action);
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break;
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case TCP_FIN:
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debug_cond(DEBUG_DEV_PKT,
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"TCP Hdr:FIN (%pI4, %pI4, s=%d, a=%d)\n",
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&net_server_ip, &net_ip, tcp_seq_num, tcp_ack_num);
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payload_len = 0;
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pkt_hdr_len = IP_TCP_HDR_SIZE;
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current_tcp_state = TCP_FIN_WAIT_1;
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break;
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/* Notify connection closing */
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case (TCP_FIN | TCP_ACK):
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case (TCP_FIN | TCP_ACK | TCP_PUSH):
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if (current_tcp_state == TCP_CLOSE_WAIT)
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current_tcp_state = TCP_CLOSING;
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tcp_ack_edge++;
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debug_cond(DEBUG_DEV_PKT,
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"TCP Hdr:FIN ACK PSH(%pI4, %pI4, s=%d, a=%d, A=%x)\n",
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&net_server_ip, &net_ip,
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tcp_seq_num, tcp_ack_edge, action);
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fallthrough;
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default:
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pkt_hdr_len = IP_HDR_SIZE + net_set_ack_options(b);
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b->ip.hdr.tcp_flags = action | TCP_PUSH | TCP_ACK;
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debug_cond(DEBUG_DEV_PKT,
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"TCP Hdr:dft (%pI4, %pI4, s=%d, a=%d, A=%x)\n",
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&net_server_ip, &net_ip,
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tcp_seq_num, tcp_ack_num, action);
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}
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pkt_len = pkt_hdr_len + payload_len;
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tcp_len = pkt_len - IP_HDR_SIZE;
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/* TCP Header */
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b->ip.hdr.tcp_ack = htonl(tcp_ack_edge);
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b->ip.hdr.tcp_src = htons(sport);
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b->ip.hdr.tcp_dst = htons(dport);
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b->ip.hdr.tcp_seq = htonl(tcp_seq_num);
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tcp_seq_num = tcp_seq_num + payload_len;
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/*
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* TCP window size - TCP header variable tcp_win.
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* Change tcp_win only if you have an understanding of network
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* overrun, congestion, TCP segment sizes, TCP windows, TCP scale,
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* queuing theory and packet buffering. If there are too few buffers,
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* there will be data loss, recovery may work or the sending TCP,
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* the server, could abort the stream transmission.
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* MSS is governed by maximum Ethernet frame length.
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* The number of buffers is governed by the desire to have a queue of
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* full buffers to be processed at the destination to maximize
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* throughput. Temporary memory use for the boot phase on modern
|
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* SOCs is may not be considered a constraint to buffer space, if
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* it is, then the u-boot tftp or nfs kernel netboot should be
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* considered.
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*/
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b->ip.hdr.tcp_win = htons(PKTBUFSRX * TCP_MSS >> TCP_SCALE);
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b->ip.hdr.tcp_xsum = 0;
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b->ip.hdr.tcp_ugr = 0;
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b->ip.hdr.tcp_xsum = tcp_set_pseudo_header(pkt, net_ip, net_server_ip,
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tcp_len, pkt_len);
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net_set_ip_header((uchar *)&b->ip, net_server_ip, net_ip,
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pkt_len, IPPROTO_TCP);
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return pkt_hdr_len;
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}
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|
||
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/**
|
||
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* tcp_hole() - Selective Acknowledgment (Essential for fast stream transfer)
|
||
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* @tcp_seq_num: TCP sequence start number
|
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* @len: the length of sequence numbers
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* @tcp_seq_max: maximum of sequence numbers
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*/
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void tcp_hole(u32 tcp_seq_num, u32 len, u32 tcp_seq_max)
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{
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u32 idx_sack, sack_in;
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u32 sack_end = TCP_SACK - 1;
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u32 hill = 0;
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enum pkt_state expect = PKT;
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u32 seq = tcp_seq_num - tcp_seq_init;
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u32 hol_l = tcp_ack_edge - tcp_seq_init;
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u32 hol_r = 0;
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/* Place new seq number in correct place in receive array */
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if (prev_len == 0)
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prev_len = len;
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idx_sack = sack_idx + ((tcp_seq_num - tcp_ack_edge) / prev_len);
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if (idx_sack < TCP_SACK) {
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edge_a[idx_sack].se.l = tcp_seq_num;
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edge_a[idx_sack].se.r = tcp_seq_num + len;
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edge_a[idx_sack].st = PKT;
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/*
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||
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* The fin (last) packet is not the same length as data
|
||
|
* packets, and if it's length is recorded and used for
|
||
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* array index calculation, calculation breaks.
|
||
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*/
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if (prev_len < len)
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prev_len = len;
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}
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debug_cond(DEBUG_DEV_PKT,
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||
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"TCP 1 seq %d, edg %d, len %d, sack_idx %d, sack_end %d\n",
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||
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seq, hol_l, len, sack_idx, sack_end);
|
||
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||
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/* Right edge of contiguous stream, is the left edge of first hill */
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||
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hol_l = tcp_seq_num - tcp_seq_init;
|
||
|
hol_r = hol_l + len;
|
||
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|
||
|
if (IS_ENABLED(CONFIG_PROT_TCP_SACK))
|
||
|
tcp_lost.len = TCP_OPT_LEN_2;
|
||
|
|
||
|
debug_cond(DEBUG_DEV_PKT,
|
||
|
"TCP 1 in %d, seq %d, pkt_l %d, pkt_r %d, sack_idx %d, sack_end %d\n",
|
||
|
idx_sack, seq, hol_l, hol_r, sack_idx, sack_end);
|
||
|
|
||
|
for (sack_in = sack_idx; sack_in < sack_end && hill < TCP_SACK_HILLS;
|
||
|
sack_in++) {
|
||
|
switch (expect) {
|
||
|
case NOPKT:
|
||
|
switch (edge_a[sack_in].st) {
|
||
|
case NOPKT:
|
||
|
debug_cond(DEBUG_INT_STATE, "N");
|
||
|
break;
|
||
|
case PKT:
|
||
|
debug_cond(DEBUG_INT_STATE, "n");
|
||
|
if (IS_ENABLED(CONFIG_PROT_TCP_SACK)) {
|
||
|
tcp_lost.hill[hill].l =
|
||
|
edge_a[sack_in].se.l;
|
||
|
tcp_lost.hill[hill].r =
|
||
|
edge_a[sack_in].se.r;
|
||
|
}
|
||
|
expect = PKT;
|
||
|
break;
|
||
|
}
|
||
|
break;
|
||
|
case PKT:
|
||
|
switch (edge_a[sack_in].st) {
|
||
|
case NOPKT:
|
||
|
debug_cond(DEBUG_INT_STATE, "p");
|
||
|
if (sack_in > sack_idx &&
|
||
|
hill < TCP_SACK_HILLS) {
|
||
|
hill++;
|
||
|
if (IS_ENABLED(CONFIG_PROT_TCP_SACK))
|
||
|
tcp_lost.len += TCP_OPT_LEN_8;
|
||
|
}
|
||
|
expect = NOPKT;
|
||
|
break;
|
||
|
case PKT:
|
||
|
debug_cond(DEBUG_INT_STATE, "P");
|
||
|
|
||
|
if (tcp_ack_edge == edge_a[sack_in].se.l) {
|
||
|
tcp_ack_edge = edge_a[sack_in].se.r;
|
||
|
edge_a[sack_in].st = NOPKT;
|
||
|
sack_idx++;
|
||
|
} else {
|
||
|
if (IS_ENABLED(CONFIG_PROT_TCP_SACK) &&
|
||
|
hill < TCP_SACK_HILLS)
|
||
|
tcp_lost.hill[hill].r =
|
||
|
edge_a[sack_in].se.r;
|
||
|
if (IS_ENABLED(CONFIG_PROT_TCP_SACK) &&
|
||
|
sack_in == sack_end - 1)
|
||
|
tcp_lost.hill[hill].r =
|
||
|
edge_a[sack_in].se.r;
|
||
|
}
|
||
|
break;
|
||
|
}
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
debug_cond(DEBUG_INT_STATE, "\n");
|
||
|
if (!IS_ENABLED(CONFIG_PROT_TCP_SACK) || tcp_lost.len <= TCP_OPT_LEN_2)
|
||
|
sack_idx = 0;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* tcp_parse_options() - parsing TCP options
|
||
|
* @o: pointer to the option field.
|
||
|
* @o_len: length of the option field.
|
||
|
*/
|
||
|
void tcp_parse_options(uchar *o, int o_len)
|
||
|
{
|
||
|
struct tcp_t_opt *tsopt;
|
||
|
uchar *p = o;
|
||
|
|
||
|
/*
|
||
|
* NOPs are options with a zero length, and thus are special.
|
||
|
* All other options have length fields.
|
||
|
*/
|
||
|
for (p = o; p < (o + o_len); p = p + p[1]) {
|
||
|
if (!p[1])
|
||
|
return; /* Finished processing options */
|
||
|
|
||
|
switch (p[0]) {
|
||
|
case TCP_O_END:
|
||
|
return;
|
||
|
case TCP_O_MSS:
|
||
|
case TCP_O_SCL:
|
||
|
case TCP_P_SACK:
|
||
|
case TCP_V_SACK:
|
||
|
break;
|
||
|
case TCP_O_TS:
|
||
|
tsopt = (struct tcp_t_opt *)p;
|
||
|
rmt_timestamp = tsopt->t_snd;
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
/* Process optional NOPs */
|
||
|
if (p[0] == TCP_O_NOP)
|
||
|
p++;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static u8 tcp_state_machine(u8 tcp_flags, u32 *tcp_seq_num, int payload_len)
|
||
|
{
|
||
|
u8 tcp_fin = tcp_flags & TCP_FIN;
|
||
|
u8 tcp_syn = tcp_flags & TCP_SYN;
|
||
|
u8 tcp_rst = tcp_flags & TCP_RST;
|
||
|
u8 tcp_push = tcp_flags & TCP_PUSH;
|
||
|
u8 tcp_ack = tcp_flags & TCP_ACK;
|
||
|
u8 action = TCP_DATA;
|
||
|
int i;
|
||
|
|
||
|
/*
|
||
|
* tcp_flags are examined to determine TX action in a given state
|
||
|
* tcp_push is interpreted to mean "inform the app"
|
||
|
* urg, ece, cer and nonce flags are not supported.
|
||
|
*
|
||
|
* exe and crw are use to signal and confirm knowledge of congestion.
|
||
|
* This TCP only sends a file request and acks. If it generates
|
||
|
* congestion, the network is broken.
|
||
|
*/
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP STATE ENTRY %x\n", action);
|
||
|
if (tcp_rst) {
|
||
|
action = TCP_DATA;
|
||
|
current_tcp_state = TCP_CLOSED;
|
||
|
net_set_state(NETLOOP_FAIL);
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP Reset %x\n", tcp_flags);
|
||
|
return TCP_RST;
|
||
|
}
|
||
|
|
||
|
switch (current_tcp_state) {
|
||
|
case TCP_CLOSED:
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP CLOSED %x\n", tcp_flags);
|
||
|
if (tcp_ack)
|
||
|
action = TCP_DATA;
|
||
|
else if (tcp_syn)
|
||
|
action = TCP_RST;
|
||
|
else if (tcp_fin)
|
||
|
action = TCP_DATA;
|
||
|
break;
|
||
|
case TCP_SYN_SENT:
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP_SYN_SENT %x, %d\n",
|
||
|
tcp_flags, *tcp_seq_num);
|
||
|
if (tcp_fin) {
|
||
|
action = action | TCP_PUSH;
|
||
|
current_tcp_state = TCP_CLOSE_WAIT;
|
||
|
}
|
||
|
if (tcp_syn) {
|
||
|
action = action | TCP_ACK | TCP_PUSH;
|
||
|
if (tcp_ack) {
|
||
|
tcp_seq_init = *tcp_seq_num;
|
||
|
*tcp_seq_num = *tcp_seq_num + 1;
|
||
|
tcp_seq_max = *tcp_seq_num;
|
||
|
tcp_ack_edge = *tcp_seq_num;
|
||
|
sack_idx = 0;
|
||
|
edge_a[sack_idx].se.l = *tcp_seq_num;
|
||
|
edge_a[sack_idx].se.r = *tcp_seq_num;
|
||
|
prev_len = 0;
|
||
|
current_tcp_state = TCP_ESTABLISHED;
|
||
|
for (i = 0; i < TCP_SACK; i++)
|
||
|
edge_a[i].st = NOPKT;
|
||
|
}
|
||
|
} else if (tcp_ack) {
|
||
|
action = TCP_DATA;
|
||
|
}
|
||
|
|
||
|
break;
|
||
|
case TCP_ESTABLISHED:
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP_ESTABLISHED %x\n", tcp_flags);
|
||
|
if (*tcp_seq_num > tcp_seq_max)
|
||
|
tcp_seq_max = *tcp_seq_num;
|
||
|
if (payload_len > 0) {
|
||
|
tcp_hole(*tcp_seq_num, payload_len, tcp_seq_max);
|
||
|
tcp_fin = TCP_DATA; /* cause standalone FIN */
|
||
|
}
|
||
|
|
||
|
if ((tcp_fin) &&
|
||
|
(!IS_ENABLED(CONFIG_PROT_TCP_SACK) ||
|
||
|
tcp_lost.len <= TCP_OPT_LEN_2)) {
|
||
|
action = action | TCP_FIN | TCP_PUSH | TCP_ACK;
|
||
|
current_tcp_state = TCP_CLOSE_WAIT;
|
||
|
} else if (tcp_ack) {
|
||
|
action = TCP_DATA;
|
||
|
}
|
||
|
|
||
|
if (tcp_syn)
|
||
|
action = TCP_ACK + TCP_RST;
|
||
|
else if (tcp_push)
|
||
|
action = action | TCP_PUSH;
|
||
|
break;
|
||
|
case TCP_CLOSE_WAIT:
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP_CLOSE_WAIT (%x)\n", tcp_flags);
|
||
|
action = TCP_DATA;
|
||
|
break;
|
||
|
case TCP_FIN_WAIT_2:
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP_FIN_WAIT_2 (%x)\n", tcp_flags);
|
||
|
if (tcp_ack) {
|
||
|
action = TCP_PUSH | TCP_ACK;
|
||
|
current_tcp_state = TCP_CLOSED;
|
||
|
puts("\n");
|
||
|
} else if (tcp_syn) {
|
||
|
action = TCP_DATA;
|
||
|
} else if (tcp_fin) {
|
||
|
action = TCP_DATA;
|
||
|
}
|
||
|
break;
|
||
|
case TCP_FIN_WAIT_1:
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP_FIN_WAIT_1 (%x)\n", tcp_flags);
|
||
|
if (tcp_fin) {
|
||
|
action = TCP_ACK | TCP_FIN;
|
||
|
current_tcp_state = TCP_FIN_WAIT_2;
|
||
|
}
|
||
|
if (tcp_syn)
|
||
|
action = TCP_RST;
|
||
|
if (tcp_ack) {
|
||
|
current_tcp_state = TCP_CLOSED;
|
||
|
tcp_seq_num = tcp_seq_num + 1;
|
||
|
}
|
||
|
break;
|
||
|
case TCP_CLOSING:
|
||
|
debug_cond(DEBUG_INT_STATE, "TCP_CLOSING (%x)\n", tcp_flags);
|
||
|
if (tcp_ack) {
|
||
|
action = TCP_PUSH;
|
||
|
current_tcp_state = TCP_CLOSED;
|
||
|
puts("\n");
|
||
|
} else if (tcp_syn) {
|
||
|
action = TCP_RST;
|
||
|
} else if (tcp_fin) {
|
||
|
action = TCP_DATA;
|
||
|
}
|
||
|
break;
|
||
|
}
|
||
|
return action;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* rxhand_tcp_f() - process receiving data and call data handler.
|
||
|
* @b: the packet
|
||
|
* @pkt_len: the length of packet.
|
||
|
*/
|
||
|
void rxhand_tcp_f(union tcp_build_pkt *b, unsigned int pkt_len)
|
||
|
{
|
||
|
int tcp_len = pkt_len - IP_HDR_SIZE;
|
||
|
u16 tcp_rx_xsum = b->ip.hdr.ip_sum;
|
||
|
u8 tcp_action = TCP_DATA;
|
||
|
u32 tcp_seq_num, tcp_ack_num;
|
||
|
struct in_addr action_and_state;
|
||
|
int tcp_hdr_len, payload_len;
|
||
|
|
||
|
/* Verify IP header */
|
||
|
debug_cond(DEBUG_DEV_PKT,
|
||
|
"TCP RX in RX Sum (to=%pI4, from=%pI4, len=%d)\n",
|
||
|
&b->ip.hdr.ip_src, &b->ip.hdr.ip_dst, pkt_len);
|
||
|
|
||
|
b->ip.hdr.ip_src = net_server_ip;
|
||
|
b->ip.hdr.ip_dst = net_ip;
|
||
|
b->ip.hdr.ip_sum = 0;
|
||
|
if (tcp_rx_xsum != compute_ip_checksum(b, IP_HDR_SIZE)) {
|
||
|
debug_cond(DEBUG_DEV_PKT,
|
||
|
"TCP RX IP xSum Error (%pI4, =%pI4, len=%d)\n",
|
||
|
&net_ip, &net_server_ip, pkt_len);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
/* Build pseudo header and verify TCP header */
|
||
|
tcp_rx_xsum = b->ip.hdr.tcp_xsum;
|
||
|
b->ip.hdr.tcp_xsum = 0;
|
||
|
if (tcp_rx_xsum != tcp_set_pseudo_header((uchar *)b, b->ip.hdr.ip_src,
|
||
|
b->ip.hdr.ip_dst, tcp_len,
|
||
|
pkt_len)) {
|
||
|
debug_cond(DEBUG_DEV_PKT,
|
||
|
"TCP RX TCP xSum Error (%pI4, %pI4, len=%d)\n",
|
||
|
&net_ip, &net_server_ip, tcp_len);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
tcp_hdr_len = GET_TCP_HDR_LEN_IN_BYTES(b->ip.hdr.tcp_hlen);
|
||
|
payload_len = tcp_len - tcp_hdr_len;
|
||
|
|
||
|
if (tcp_hdr_len > TCP_HDR_SIZE)
|
||
|
tcp_parse_options((uchar *)b + IP_TCP_HDR_SIZE,
|
||
|
tcp_hdr_len - TCP_HDR_SIZE);
|
||
|
/*
|
||
|
* Incoming sequence and ack numbers are server's view of the numbers.
|
||
|
* The app must swap the numbers when responding.
|
||
|
*/
|
||
|
tcp_seq_num = ntohl(b->ip.hdr.tcp_seq);
|
||
|
tcp_ack_num = ntohl(b->ip.hdr.tcp_ack);
|
||
|
|
||
|
/* Packets are not ordered. Send to app as received. */
|
||
|
tcp_action = tcp_state_machine(b->ip.hdr.tcp_flags,
|
||
|
&tcp_seq_num, payload_len);
|
||
|
|
||
|
tcp_activity_count++;
|
||
|
if (tcp_activity_count > TCP_ACTIVITY) {
|
||
|
puts("| ");
|
||
|
tcp_activity_count = 0;
|
||
|
}
|
||
|
|
||
|
if ((tcp_action & TCP_PUSH) || payload_len > 0) {
|
||
|
debug_cond(DEBUG_DEV_PKT,
|
||
|
"TCP Notify (action=%x, Seq=%d,Ack=%d,Pay%d)\n",
|
||
|
tcp_action, tcp_seq_num, tcp_ack_num, payload_len);
|
||
|
|
||
|
action_and_state.s_addr = tcp_action;
|
||
|
(*tcp_packet_handler) ((uchar *)b + pkt_len - payload_len,
|
||
|
tcp_seq_num, action_and_state,
|
||
|
tcp_ack_num, payload_len);
|
||
|
|
||
|
} else if (tcp_action != TCP_DATA) {
|
||
|
debug_cond(DEBUG_DEV_PKT,
|
||
|
"TCP Action (action=%x,Seq=%d,Ack=%d,Pay=%d)\n",
|
||
|
tcp_action, tcp_seq_num, tcp_ack_num, payload_len);
|
||
|
|
||
|
/*
|
||
|
* Warning: Incoming Ack & Seq sequence numbers are transposed
|
||
|
* here to outgoing Seq & Ack sequence numbers
|
||
|
*/
|
||
|
net_send_tcp_packet(0, ntohs(b->ip.hdr.tcp_src),
|
||
|
ntohs(b->ip.hdr.tcp_dst),
|
||
|
(tcp_action & (~TCP_PUSH)),
|
||
|
tcp_seq_num, tcp_ack_num);
|
||
|
}
|
||
|
}
|