[PATCH v6 06/12] net/tcp: improve tcp framework, use better state machine

10 Sep 2024

Changes:
 * Fix initial send sequence always zero issue
 * Use state machine close to RFC 9293. This should make TCP
   transfers more reliable (now we can upload a huge array
   of data from the board to external server)
 * Improve TCP framework a lot. This should make tcp client
   code much more simple.
 * rewrite wget with new tcp stack
 * rewrite fastboot_tcp with new tcp stack
It's quite hard to fix the initial send sequence (ISS) issue
with the separate patch. A naive attempt to fix an issue
inside the tcp_set_tcp_header() function will break tcp packet
retransmit logic in wget and other clients.
Example:
  Wget stores tcp_seq_num value before tcp_set_tcp_header() will
  be called and (on failure) retransmit the packet with the stored
  tcp_seq_num value. Thus:
    * the same ISS must allways be used (current case)
    * or tcp clients needs to generate a proper ISS when
      required.
A proper ISS fix will require a big redesing comparable with
a this one.
Signed-off-by: Mikhail Kshevetskiy mikhail.kshevetskiy@iopsys.eu
---
 include/net/tcp.h  | 179 ++++++++--
 include/net/wget.h |   8 -
 net/fastboot_tcp.c | 190 +++++-----
 net/net.c          |   4 +
 net/tcp.c          | 845 ++++++++++++++++++++++++++++++++++-----------
 net/wget.c         | 460 +++++++-----------------
 6 files changed, 1008 insertions(+), 678 deletions(-)

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 0694af9d5b1..0b18475645d 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -265,6 +265,7 @@ union tcp_build_pkt {
  * @TCP_CLOSING: Rec FIN, sent FIN, ACK waiting for ACK
  * @TCP_FIN_WAIT_1: Sent FIN waiting for response
  * @TCP_FIN_WAIT_2: Rec ACK from FIN sent, waiting for FIN
+ * @TCP_LAST_ACK: Waiting for ACK of the connection termination
  */
 enum tcp_state {
    TCP_CLOSED,
@@ -274,7 +275,20 @@ enum tcp_state {
    TCP_CLOSE_WAIT,
    TCP_CLOSING,
    TCP_FIN_WAIT_1,
-	TCP_FIN_WAIT_2
+	TCP_FIN_WAIT_2,
+	TCP_LAST_ACK,
+};
+
+/**
+ * enum tcp_status - TCP stream status for connection
+ * @TCP_ERR_OK: no rx/tx errors
+ * @TCP_ERR_TOUT: rx/tx timeout happened
+ * @TCP_ERR_RST: connection was reset
+ */
+enum tcp_status {
+	TCP_ERR_OK = 0,
+	TCP_ERR_TOUT,
+	TCP_ERR_RST,
 };
/**
@@ -283,51 +297,150 @@ enum tcp_state {
  * @rport:		Remote port, host byte order
  * @lport:		Local port, host byte order
  *
+ * @priv:		User private data (not used by tcp module)
+ *
+ * @max_retry_count:	Maximum retransmit attempts (default 3)
+ * @initial_timeout:	Timeout from initial TX to reTX (default 2 sec)
+ * @rx_inactiv_timeout:	Maximum time from last rx till connection drop
+ *			  (default 30 sec)
+ *
+ * @on_closed:		User callback, called just before destroying TCP stream
+ * @on_established:	User callback, called when TCP stream enters
+ *			  TCP_ESTABLISHED state
+ * @on_rcv_nxt_update:	User callback, called when all data in the segment
+ *			  [0..rx_bytes - 1] was received
+ * @on_snd_una_update:	User callback, called when all data in the segment
+ *			  [0..tx_bytes - 1] were transferred and acknowledged
+ * @rx:			User callback, called on receive of segment
+ *			  [rx_offs..rx_offs+len-1]. If NULL -- all incoming data
+ *			  will be ignored. User SHOULD store the segment and
+ *			  return the number of accepted bytes.
+ *			  WARNING: Previous segmengs may not be received yet
+ * @tx:			User callback, called on transmit/retransmit of segment
+ *			  [tx_offs..tx_offs+maxlen-1]. If NULL -- no data will
+ *			  be transmitted. User SHOULD fill provided buffer and
+ *			  return the number of bytes in the buffer.
+ *			  WARNING: do not use tcp_stream_close() from this
+ *			    callback (it will break stream). Better use
+ *			    on_snd_una_update() callback for such purposes.
+ *
+ * @time_last_rx:	Arrival time of last valid incoming package (ticks)
+ * @time_start:		Timeout start time (ticks)
+ * @time_delta:		Timeout duration (ticks)
+ * @time_handler	Timeout handler for a stream
+ *
  * @state:		TCP connection state
+ * @status:		TCP stream status (OK or ERR)
+ *
+ * @fin_rx:		Non-zero if TCP_FIN was received
+ * @fin_rx_seq:		TCP sequence of rx FIN bit
+ * @fin_tx:		Non-zero if TCP_FIN was sent (or planned to send)
+ * @fin_tx_seq:		TCP sequence of tx FIN bit
+ *
+ * @iss:		Initial send sequence number
+ * @snd_una:		Send unacknowledged
+ * @snd_nxt:		Send next
+ * @snd_wnd:		Send window (in bytes)
+ * @snd_wl1:		Segment sequence number used for last window update
+ * @snd_wl2:		Segment acknowledgment number used for last window update
  *
  * @irs:		Initial receive sequence number
  * @rcv_nxt:		Receive next
+ * @rcv_wnd:		Receive window (in bytes)
  *
  * @loc_timestamp:	Local timestamp
  * @rmt_timestamp:	Remote timestamp
  *
+ * @rmt_win_scale:	Remote window scale factor
+ *
  * @lost:		Used for SACK
+ *
+ * @retry_cnt:		Number of retry attempts remaining. Only SYN, FIN
+ *			  or DATA segments are tried to retransmit.
+ * @retry_timeout:	Current retry timeout (ms)
+ * @retry_action:	TCP flags used for sending
+ * @retry_seq_num:	TCP sequence for retransmit
+ * retry_tx_len:	Number of data to transmit
+ * @retry_tx_offs:	Position in the TX stream
  */
 struct tcp_stream {
    struct in_addr	rhost;
    u16		rport;
    u16		lport;
-	/* TCP connection state */
+	void		*priv;
+
+	int		max_retry_count;
+	int		initial_timeout;
+	int		rx_inactiv_timeout;
+
+	void		(*on_closed)(struct tcp_stream *tcp);
+	void		(*on_established)(struct tcp_stream *tcp);
+	void		(*on_rcv_nxt_update)(struct tcp_stream *tcp, u32 rx_bytes);
+	void		(*on_snd_una_update)(struct tcp_stream *tcp, u32 tx_bytes);
+	u32		(*rx)(struct tcp_stream *tcp, u32 rx_offs, void *buf, u32 len);
+	u32		(*tx)(struct tcp_stream *tcp, u32 tx_offs, void *buf, u32 maxlen);
+
+	ulong		time_last_rx;
+	ulong		time_start;
+	ulong		time_delta;
+	void		(*time_handler)(struct tcp_stream *tcp);
+
    enum tcp_state	state;
+	enum tcp_status	status;
+
+	int		fin_rx;
+	u32		fin_rx_seq;
+
+	int		fin_tx;
+	u32		fin_tx_seq;
+
+	u32		iss;
+	u32		snd_una;
+	u32		snd_nxt;
+	u32		snd_wnd;
+	u32		snd_wl1;
+	u32		snd_wl2;
u32		irs;
    u32		rcv_nxt;
+	u32		rcv_wnd;
/* TCP option timestamp */
    u32		loc_timestamp;
    u32		rmt_timestamp;
+	/* TCP window scale */
+	u8		rmt_win_scale;
+
    /* TCP sliding window control used to request re-TX */
    struct tcp_sack_v lost;
+
+	/* used for data retransmission */
+	int		retry_cnt;
+	int		retry_timeout;
+	u8		retry_action;
+	u32		retry_seq_num;
+	u32		retry_tx_len;
+	u32		retry_tx_offs;
 };
void tcp_init(void);
-typedef int tcp_incoming_filter(struct in_addr rhost,
-				u16 rport, u16 sport);
-
 /*
- * This function sets user callback used to accept/drop incoming
- * connections. Callback should:
+ * This function sets user callback called on TCP stream creation.
+ * Callback should:
  *  + Check TCP stream endpoint and make connection verdict
  *    - return non-zero value to accept connection
  *    - return zero to drop connection
+ *  + Setup TCP stream callbacks like: on_closed(), on_established(),
+ *    n_rcv_nxt_update(), on_snd_una_update(), rx() and tx().
+ *  + Setup other stream related data
  *
- * WARNING: If callback is NOT defined, all incoming connections
- *          will be dropped.
+ * WARNING: User MUST setup TCP stream on_create handler. Without it
+ *          no connection (including outgoung) will be created.
  */
-void tcp_set_incoming_filter(tcp_incoming_filter *filter);
+void tcp_stream_set_on_create_handler(int (*on_create)(struct tcp_stream *));
/*
  * tcp_stream_get -- Get or create TCP stream
@@ -351,27 +464,37 @@ struct tcp_stream *tcp_stream_get(int is_new, struct in_addr rhost,
  */
 struct tcp_stream *tcp_stream_connect(struct in_addr rhost, u16 rport);
-enum tcp_state tcp_stream_get_state(struct tcp_stream *tcp);
+/*
+ * tcp_stream_put -- Return stream to a TCP subsystem. Subsystem will
+ *                   check stream and destroy it (if stream was already
+ *                   closed). Otherwize no stream change will happen.
+ * @tcp:	TCP stream to put
+ */
+void tcp_stream_put(struct tcp_stream *tcp);
-int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int payload_len,
-		       u8 action, u32 tcp_seq_num, u32 tcp_ack_num);
+enum tcp_state  tcp_stream_get_state(struct tcp_stream *tcp);
+enum tcp_status tcp_stream_get_status(struct tcp_stream *tcp);
-/**
- * rxhand_tcp() - An incoming packet handler.
- * @tcp: TCP stream
- * @pkt: pointer to the application packet
- * @dport: destination TCP port
- * @sip: source IP address
- * @sport: source TCP port
- * @tcp_seq_num: TCP sequential number
- * @tcp_ack_num: TCP acknowledgment number
- * @action: TCP action (SYN, ACK, FIN, etc)
- * @len: packet length
+
+/*
+ * tcp_stream_rx_offs(),
+ * tcp_stream_tx_offs()  -- Returns offset of first unacknowledged byte
+ *                          in receive/transmit stream correspondingly.
+ *                          The result is NOT affected by sin/fin flags.
+ * @tcp:	TCP stream
  */
-typedef void rxhand_tcp(struct tcp_stream *tcp, uchar *pkt,
-			u32 tcp_seq_num, u32 tcp_ack_num,
-			u8 action, unsigned int len);
-void tcp_set_tcp_handler(rxhand_tcp *f);
+u32 tcp_stream_rx_offs(struct tcp_stream *tcp);
+u32 tcp_stream_tx_offs(struct tcp_stream *tcp);
+
+/* reset tcp stream */
+void tcp_stream_reset(struct tcp_stream *tcp);
+/* force TCP stream closing, do NOT use from tcp->tx callback */
+void tcp_stream_close(struct tcp_stream *tcp);
+
+void tcp_streams_poll(void);
+
+int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int payload_len,
+		       u8 action, u32 tcp_seq_num, u32 tcp_ack_num);
void rxhand_tcp_f(union tcp_build_pkt *b, unsigned int len);
diff --git a/include/net/wget.h b/include/net/wget.h
index 6714f7ea573..9a423b30414 100644
--- a/include/net/wget.h
+++ b/include/net/wget.h
@@ -8,14 +8,6 @@
  */
 void wget_start(void);
-enum wget_state {
-	WGET_CLOSED,
-	WGET_CONNECTING,
-	WGET_CONNECTED,
-	WGET_TRANSFERRING,
-	WGET_TRANSFERRED
-};
-
 #define DEBUG_WGET		0	/* Set to 1 for debug messages */
 #define WGET_RETRY_COUNT	30
 #define WGET_TIMEOUT		2000UL
diff --git a/net/fastboot_tcp.c b/net/fastboot_tcp.c
index 4d34fdc5a45..b6f7c417a21 100644
--- a/net/fastboot_tcp.c
+++ b/net/fastboot_tcp.c
@@ -10,140 +10,106 @@
#define FASTBOOT_TCP_PORT	5554
-static char command[FASTBOOT_COMMAND_LEN];
-static char response[FASTBOOT_RESPONSE_LEN];
-
 static const unsigned short handshake_length = 4;
 static const uchar *handshake = "FB01";
-static u32 curr_tcp_seq_num;
-static u32 curr_tcp_ack_num;
-static unsigned int curr_request_len;
-static enum fastboot_tcp_state {
-	FASTBOOT_CLOSED,
-	FASTBOOT_CONNECTED,
-	FASTBOOT_DISCONNECTING
-} state = FASTBOOT_CLOSED;
-
-static void fastboot_tcp_answer(struct tcp_stream *tcp, u8 action,
-				unsigned int len)
-{
-	const u32 response_seq_num = curr_tcp_ack_num;
-	const u32 response_ack_num = curr_tcp_seq_num +
-		  (curr_request_len > 0 ? curr_request_len : 1);
+static char rxbuf[sizeof(u64) + FASTBOOT_COMMAND_LEN + 1];
+static char txbuf[sizeof(u64) + FASTBOOT_RESPONSE_LEN + 1];
-	net_send_tcp_packet(len, tcp->rhost, tcp->rport, tcp->lport,
-			    action, response_seq_num, response_ack_num);
-}
+static u32 data_read;
+static u32 tx_last_offs, tx_last_len;
-static void fastboot_tcp_reset(struct tcp_stream *tcp)
+static void tcp_stream_on_rcv_nxt_update(struct tcp_stream *tcp, u32 rx_bytes)
 {
-	fastboot_tcp_answer(tcp, TCP_RST, 0);
-	state = FASTBOOT_CLOSED;
-}
+	u64	cmd_size;
+	__be64	len_be;
+	char	saved;
+	int	fastboot_command_id, len;
+
+	if ((data_read == 0) && (rx_bytes >= handshake_length)) {
+		if (memcmp(rxbuf, handshake, handshake_length) != 0) {
+			printf("fastboot: bad handshake\n");
+			tcp_stream_close(tcp);
+			return;
+		}
-static void fastboot_tcp_send_packet(struct tcp_stream *tcp, u8 action,
-				     const uchar *data, unsigned int len)
-{
-	uchar *pkt = net_get_async_tx_pkt_buf();
+		tx_last_offs = 0;
+		tx_last_len = handshake_length;
+		memcpy(txbuf, handshake, handshake_length);
+
+		data_read += handshake_length;
+		rx_bytes -= handshake_length;
+		if (rx_bytes > 0)
+			memmove(rxbuf, rxbuf + handshake_length, rx_bytes);
+		return;
+	}
-	memset(pkt, '\0', PKTSIZE);
-	pkt += net_eth_hdr_size() + IP_TCP_HDR_SIZE + TCP_TSOPT_SIZE + 2;
-	memcpy(pkt, data, len);
-	fastboot_tcp_answer(tcp, action, len);
-	memset(pkt, '\0', PKTSIZE);
+	if (rx_bytes < sizeof(u64))
+		return;
+
+	memcpy(&cmd_size, rxbuf, sizeof(u64));
+	cmd_size = __be64_to_cpu(cmd_size);
+	if (rx_bytes < sizeof(u64) + cmd_size)
+		return;
+
+	saved = rxbuf[sizeof(u64) + cmd_size];
+	rxbuf[sizeof(u64) + cmd_size] = '\0';
+	fastboot_command_id = fastboot_handle_command(rxbuf + sizeof(u64),
+						      txbuf + sizeof(u64));
+	fastboot_handle_boot(fastboot_command_id,
+			     strncmp("OKAY", txbuf + sizeof(u64), 4) != 0);
+	rxbuf[sizeof(u64) + cmd_size] = saved;
+
+	len = strlen(txbuf + sizeof(u64));
+	len_be = __cpu_to_be64(len);
+	memcpy(txbuf, &len_be, sizeof(u64));
+
+	tx_last_offs += tx_last_len;
+	tx_last_len = len + sizeof(u64);
+
+	data_read += sizeof(u64) + cmd_size;
+	rx_bytes -= sizeof(u64) + cmd_size;
+	if (rx_bytes > 0)
+		memmove(rxbuf, rxbuf + sizeof(u64) + cmd_size, rx_bytes);
 }
-static void fastboot_tcp_send_message(struct tcp_stream *tcp,
-				      const char *message, unsigned int len)
+static u32 tcp_stream_rx(struct tcp_stream *tcp, u32 rx_offs, void *buf, u32 len)
 {
-	__be64 len_be = __cpu_to_be64(len);
-	uchar *pkt = net_get_async_tx_pkt_buf();
-
-	memset(pkt, '\0', PKTSIZE);
-	pkt += net_eth_hdr_size() + IP_TCP_HDR_SIZE + TCP_TSOPT_SIZE + 2;
-	// Put first 8 bytes as a big endian message length
-	memcpy(pkt, &len_be, 8);
-	pkt += 8;
-	memcpy(pkt, message, len);
-	fastboot_tcp_answer(tcp, TCP_ACK | TCP_PUSH, len + 8);
-	memset(pkt, '\0', PKTSIZE);
+	memcpy(rxbuf + rx_offs - data_read, buf, len);
+	return len;
 }
-static void fastboot_tcp_handler_ipv4(struct tcp_stream *tcp, uchar *pkt,
-				      u32 tcp_seq_num, u32 tcp_ack_num,
-				      u8 action, unsigned int len)
+static u32 tcp_stream_tx(struct tcp_stream *tcp, u32 tx_offs, void *buf, u32 maxlen)
 {
-	int fastboot_command_id;
-	u64 command_size;
-	u8 tcp_fin = action & TCP_FIN;
-	u8 tcp_push = action & TCP_PUSH;
-
-	curr_tcp_seq_num = tcp_seq_num;
-	curr_tcp_ack_num = tcp_ack_num;
-	curr_request_len = len;
-
-	switch (state) {
-	case FASTBOOT_CLOSED:
-		if (tcp_push) {
-			if (len != handshake_length ||
-			    strlen(pkt) != handshake_length ||
-			    memcmp(pkt, handshake, handshake_length) != 0) {
-				fastboot_tcp_reset(tcp);
-				break;
-			}
-			fastboot_tcp_send_packet(tcp, TCP_ACK | TCP_PUSH,
-						 handshake, handshake_length);
-			state = FASTBOOT_CONNECTED;
-		}
-		break;
-	case FASTBOOT_CONNECTED:
-		if (tcp_fin) {
-			fastboot_tcp_answer(tcp, TCP_FIN | TCP_ACK, 0);
-			state = FASTBOOT_DISCONNECTING;
-			break;
-		}
-		if (tcp_push) {
-			// First 8 bytes is big endian message length
-			command_size = __be64_to_cpu(*(u64 *)pkt);
-			len -= 8;
-			pkt += 8;
-
-			// Only single packet messages are supported ATM
-			if (strlen(pkt) != command_size) {
-				fastboot_tcp_reset(tcp);
-				break;
-			}
-			strlcpy(command, pkt, len + 1);
-			fastboot_command_id = fastboot_handle_command(command, response);
-			fastboot_tcp_send_message(tcp, response, strlen(response));
-			fastboot_handle_boot(fastboot_command_id,
-					     strncmp("OKAY", response, 4) == 0);
-		}
-		break;
-	case FASTBOOT_DISCONNECTING:
-		if (tcp_push)
-			state = FASTBOOT_CLOSED;
-		break;
-	}
+	/* by design: tx_offs >= tx_last_offs */
+	if (tx_offs >= tx_last_offs + tx_last_len)
+		return 0;
-	memset(command, 0, FASTBOOT_COMMAND_LEN);
-	memset(response, 0, FASTBOOT_RESPONSE_LEN);
-	curr_tcp_seq_num = 0;
-	curr_tcp_ack_num = 0;
-	curr_request_len = 0;
+	maxlen = tx_last_offs + tx_last_len - tx_offs;
+	memcpy(buf, txbuf + (tx_offs - tx_last_offs), maxlen);
+	return maxlen;
 }
-static int incoming_filter(struct in_addr rhost, u16 rport, u16 lport)
+static int tcp_stream_on_create(struct tcp_stream *tcp)
 {
-	return (lport == FASTBOOT_TCP_PORT);
+	if (tcp->lport != FASTBOOT_TCP_PORT)
+		return 0;
+
+	data_read = 0;
+	tx_last_offs = 0;
+	tx_last_len = 0;
+
+	tcp->on_rcv_nxt_update = tcp_stream_on_rcv_nxt_update;
+	tcp->rx = tcp_stream_rx;
+	tcp->tx = tcp_stream_tx;
+	return 1;
 }
void fastboot_tcp_start_server(void)
 {
+	memset(net_server_ethaddr, 0, 6);
+	tcp_stream_set_on_create_handler(tcp_stream_on_create);
+
    printf("Using %s device\n", eth_get_name());
    printf("Listening for fastboot command on tcp %pI4\n", &net_ip);
-
-	tcp_set_incoming_filter(incoming_filter);
-	tcp_set_tcp_handler(fastboot_tcp_handler_ipv4);
 }
diff --git a/net/net.c b/net/net.c
index b33ea59a9fa..86182cc504e 100644
--- a/net/net.c
+++ b/net/net.c
@@ -646,6 +646,9 @@ restart:
    	 *	errors that may have happened.
    	 */
    	eth_rx();
+#if defined(CONFIG_PROT_TCP)
+		tcp_streams_poll();
+#endif
/*
    	 *	Abort if ctrl-c was pressed.
@@ -952,6 +955,7 @@ int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
    		+ tcp_set_tcp_header(tcp, pkt + eth_hdr_size,
    				     payload_len, action, tcp_seq_num,
    				     tcp_ack_num);
+		tcp_stream_put(tcp);
    	break;
 #endif
    default:
diff --git a/net/tcp.c b/net/tcp.c
index 7e445eaffd6..37dda6f84f9 100644
--- a/net/tcp.c
+++ b/net/tcp.c
@@ -24,9 +24,26 @@
 #include <net.h>
 #include <net/tcp.h>
-static int tcp_activity_count;
+/*
+ * The start sequence number increment for the two sequently created
+ * connections within the same timer tick. This number must be:
+ *  - prime (to increase the time before the same number will be generated)
+ *  - larger than typical MTU (to avoid similar numbers for two sequently
+ *    created connections)
+ */
+#define TCP_START_SEQ_INC	2153	/* just large prime number */
+
+#define TCP_SEND_RETRY		3
+#define TCP_SEND_TIMEOUT	2000UL
+#define TCP_RX_INACTIVE_TIMEOUT	30000UL
+#define TCP_RCV_WND_SIZE	(PKTBUFSRX * TCP_MSS)
+
+#define TCP_PACKET_OK		0
+#define TCP_PACKET_DROP		1
+
 static struct tcp_stream tcp_stream;
-static tcp_incoming_filter *incoming_filter;
+
+static int (*tcp_stream_on_create)(struct tcp_stream *tcp);
/*
  * TCP lengths are stored as a rounded up number of 32 bit words.
@@ -35,12 +52,10 @@ static tcp_incoming_filter *incoming_filter;
  */
 #define LEN_B_TO_DW(x) ((x) >> 2)
 #define ROUND_TCPHDR_LEN(x) (LEN_B_TO_DW((x) + 3))
+#define ROUND_TCPHDR_BYTES(x) (((x) + 3) & ~3)
 #define SHIFT_TO_TCPHDRLEN_FIELD(x) ((x) << 4)
 #define GET_TCP_HDR_LEN_IN_BYTES(x) ((x) >> 2)
-/* Current TCP RX packet handler */
-static rxhand_tcp *tcp_packet_handler;
-
 #define RANDOM_PORT_START 1024
 #define RANDOM_PORT_RANGE 0x4000
@@ -62,6 +77,21 @@ static inline s32 tcp_seq_cmp(u32 a, u32 b)
    return (s32)(a - b);
 }
+static inline u32 tcp_get_start_seq(void)
+{
+	static u32	tcp_seq_inc;
+	u32		tcp_seq;
+
+	tcp_seq = (get_timer(0) & 0xffffffff) + tcp_seq_inc;
+	tcp_seq_inc += TCP_START_SEQ_INC;
+	return tcp_seq;
+}
+
+static inline ulong msec_to_ticks(ulong msec)
+{
+	return msec * CONFIG_SYS_HZ / 1000;
+}
+
 /**
  * tcp_stream_get_state() - get TCP stream state
  * @tcp: tcp stream
@@ -84,15 +114,70 @@ static void tcp_stream_set_state(struct tcp_stream *tcp,
    tcp->state = new_state;
 }
+/**
+ * tcp_stream_get_status() - get TCP stream status
+ * @tcp: tcp stream
+ *
+ * Return: TCP stream status
+ */
+enum tcp_status tcp_stream_get_status(struct tcp_stream *tcp)
+{
+	return tcp->status;
+}
+
+/**
+ * tcp_stream_set_status() - set TCP stream state
+ * @tcp: tcp stream
+ * @new_satus: new TCP stream status
+ */
+static void tcp_stream_set_status(struct tcp_stream *tcp,
+				  enum tcp_state new_status)
+{
+	tcp->status = new_status;
+}
+
+static void tcp_stream_init(struct tcp_stream *tcp,
+			    struct in_addr rhost, u16 rport, u16 lport)
+{
+	memset(tcp, 0, sizeof(struct tcp_stream));
+	tcp->rhost.s_addr = rhost.s_addr;
+	tcp->rport = rport;
+	tcp->lport = lport;
+	tcp->state = TCP_CLOSED;
+	tcp->lost.len = TCP_OPT_LEN_2;
+	tcp->rcv_wnd = TCP_RCV_WND_SIZE;
+	tcp->max_retry_count = TCP_SEND_RETRY;
+	tcp->initial_timeout = TCP_SEND_TIMEOUT;
+	tcp->rx_inactiv_timeout = TCP_RX_INACTIVE_TIMEOUT;
+	tcp->time_last_rx = get_timer(0);
+}
+
+static void tcp_stream_destroy(struct tcp_stream *tcp)
+{
+	if (tcp->on_closed != NULL)
+		tcp->on_closed(tcp);
+	memset(tcp, 0, sizeof(struct tcp_stream));
+}
+
 void tcp_init(void)
 {
-	incoming_filter = NULL;
-	tcp_stream.state = TCP_CLOSED;
+	static int initialized;
+	struct tcp_stream *tcp = &tcp_stream;
+
+	tcp_stream_on_create = NULL;
+	if (!initialized) {
+		initialized = 1;
+		memset(tcp, 0, sizeof(struct tcp_stream));
+	}
+
+	tcp_stream_set_state(tcp, TCP_CLOSED);
+	tcp_stream_set_status(tcp, TCP_ERR_RST);
+	tcp_stream_destroy(tcp);
 }
-void tcp_set_incoming_filter(tcp_incoming_filter *filter)
+void tcp_stream_set_on_create_handler(int (*on_create)(struct tcp_stream *))
 {
-	incoming_filter = filter;
+	tcp_stream_on_create = on_create;
 }
static struct tcp_stream *tcp_stream_add(struct in_addr rhost,
@@ -100,15 +185,14 @@ static struct tcp_stream *tcp_stream_add(struct in_addr rhost,
 {
    struct tcp_stream *tcp = &tcp_stream;
-	if (tcp->state != TCP_CLOSED)
+	if ((tcp_stream_on_create == NULL) ||
+	    (tcp->state != TCP_CLOSED))
+		return NULL;
+
+	tcp_stream_init(tcp, rhost, rport, lport);
+	if (!tcp_stream_on_create(tcp))
    	return NULL;
-	memset(tcp, 0, sizeof(struct tcp_stream));
-	tcp->rhost.s_addr = rhost.s_addr;
-	tcp->rport = rport;
-	tcp->lport = lport;
-	tcp->state = TCP_CLOSED;
-	tcp->lost.len = TCP_OPT_LEN_2;
    return tcp;
 }
@@ -122,30 +206,203 @@ struct tcp_stream *tcp_stream_get(int is_new, struct in_addr rhost,
        tcp->lport == lport)
    	return tcp;
-	if (!is_new || !incoming_filter) ||
-	    !incoming_filter(rhost, rport, lport))
-		return NULL;
+	return is_new ? tcp_stream_add(rhost, rport, lport) : NULL;
+}
-	return tcp_stream_add(rhost, rport, lport);
+void tcp_stream_put(struct tcp_stream *tcp)
+{
+	if (tcp->state == TCP_CLOSED)
+		tcp_stream_destroy(tcp);
 }
-static void dummy_handler(struct tcp_stream *tcp, uchar *pkt,
-			  u32 tcp_seq_num, u32 tcp_ack_num,
-			  u8 action, unsigned int len)
+u32 tcp_stream_rx_offs(struct tcp_stream *tcp)
 {
+	u32 ret;
+
+	switch (tcp->state) {
+	case TCP_CLOSED:
+	case TCP_SYN_SENT:
+	case TCP_SYN_RECEIVED:
+		return 0;
+	default:
+		break;
+	}
+
+	ret = tcp->rcv_nxt - tcp->irs - 1;
+	if (tcp->fin_rx && (tcp->rcv_nxt == tcp->fin_rx_seq))
+		ret--;
+	return ret;
 }
-/**
- * tcp_set_tcp_handler() - set a handler to receive data
- * @f: handler
- */
-void tcp_set_tcp_handler(rxhand_tcp *f)
+u32 tcp_stream_tx_offs(struct tcp_stream *tcp)
+{
+	u32 ret;
+
+	switch (tcp->state) {
+	case TCP_CLOSED:
+	case TCP_SYN_SENT:
+	case TCP_SYN_RECEIVED:
+		return 0;
+	default:
+		break;
+	}
+
+	ret = tcp->snd_una - tcp->iss - 1;
+	if (tcp->fin_tx && (tcp->snd_una == tcp->fin_tx_seq + 1))
+		ret--;
+	return ret;
+}
+
+static void tcp_stream_set_time_handler(struct tcp_stream *tcp, ulong msec,
+					void (*handler)(struct tcp_stream *))
+{
+	if (msec == 0) {
+		tcp->time_handler = NULL;
+		return;
+	}
+
+	tcp->time_handler = handler;
+	tcp->time_start = get_timer(0);
+	tcp->time_delta = msec_to_ticks(msec);
+}
+
+static void tcp_send_packet(struct tcp_stream *tcp, u8 action,
+			    u32 tcp_seq_num, u32 tcp_ack_num, u32 tx_len)
+{
+	net_send_tcp_packet(tx_len, tcp->rhost, tcp->rport,
+			    tcp->lport, action, tcp_seq_num,
+			    tcp_ack_num);
+}
+
+static void tcp_send_repeat(struct tcp_stream *tcp)
+{
+	uchar *ptr;
+	u32 tcp_opts_size;
+
+	if (tcp->retry_cnt == 0) {
+		puts("\nTCP: send retry counter exceeded\n");
+		tcp_send_packet(tcp, TCP_RST, tcp->retry_seq_num,
+				tcp->rcv_nxt, 0);
+		tcp_stream_set_status(tcp, TCP_ERR_TOUT);
+		tcp_stream_set_state(tcp, TCP_CLOSED);
+		tcp_stream_destroy(tcp);
+		return;
+	}
+	tcp->retry_cnt--;
+	tcp->retry_timeout += tcp->initial_timeout;
+
+	if (tcp->retry_tx_len > 0) {
+		tcp_opts_size = ROUND_TCPHDR_BYTES(TCP_TSOPT_SIZE +
+						   tcp->lost.len);
+		ptr = net_tx_packet + net_eth_hdr_size() +
+			IP_TCP_HDR_SIZE + tcp_opts_size;
+
+		if (tcp->retry_tx_len > TCP_MSS - tcp_opts_size)
+			tcp->retry_tx_len = TCP_MSS - tcp_opts_size;
+
+		/* refill packet data */
+		tcp->tx(tcp, tcp->retry_tx_offs, ptr, tcp->retry_tx_len);
+	}
+	tcp_send_packet(tcp, tcp->retry_action, tcp->retry_seq_num,
+			tcp->rcv_nxt, tcp->retry_tx_len);
+
+	tcp_stream_set_time_handler(tcp, tcp->retry_timeout, tcp_send_repeat);
+}
+
+static void tcp_send_packet_with_retry(struct tcp_stream *tcp, u8 action,
+				       u32 tcp_seq_num, u32 tx_len, u32 tx_offs)
 {
-	debug_cond(DEBUG_INT_STATE, "--- net_loop TCP handler set (%p)\n", f);
-	if (!f)
-		tcp_packet_handler = dummy_handler;
-	else
-		tcp_packet_handler = f;
+	tcp->retry_cnt = tcp->max_retry_count;
+	tcp->retry_timeout = tcp->initial_timeout;
+	tcp->retry_action = action;
+	tcp->retry_seq_num = tcp_seq_num;
+	tcp->retry_tx_len = tx_len;
+	tcp->retry_tx_offs = tx_offs;
+
+	tcp_send_packet(tcp, action, tcp_seq_num, tcp->rcv_nxt, tx_len);
+	tcp_stream_set_time_handler(tcp, tcp->retry_timeout, tcp_send_repeat);
+}
+
+static inline u8 tcp_stream_fin_needed(struct tcp_stream *tcp, u32 tcp_seq_num)
+{
+	return (tcp->fin_tx && (tcp_seq_num == tcp->fin_tx_seq)) ? TCP_FIN : 0;
+}
+
+static void tcp_steam_tx_try(struct tcp_stream *tcp)
+{
+	uchar *ptr;
+	u32 tx_offs, tx_len, tcp_opts_size;
+
+	if ((tcp->state != TCP_ESTABLISHED) ||
+	    (tcp->time_handler != NULL) ||
+	    (tcp->tx == NULL))
+		return;
+
+	tcp_opts_size = ROUND_TCPHDR_BYTES(TCP_TSOPT_SIZE + tcp->lost.len);
+	tx_len = TCP_MSS - tcp_opts_size;
+	if (tcp->fin_tx) {
+		/* do not try to send beyonds FIN packet limits */
+		if (tcp_seq_cmp(tcp->snd_una, tcp->fin_tx_seq) >= 0)
+			return;
+
+		tx_len = tcp->fin_tx_seq - tcp->snd_una;
+		if (tx_len > TCP_MSS - tcp_opts_size)
+			tx_len = TCP_MSS - tcp_opts_size;
+	}
+
+	tx_offs = tcp_stream_tx_offs(tcp);
+	ptr = net_tx_packet + net_eth_hdr_size() +
+		IP_TCP_HDR_SIZE + tcp_opts_size;
+
+	/* fill packet data and adjust size */
+	tx_len = tcp->tx(tcp, tx_offs, ptr, tx_len);
+	if (tx_len == 0)
+		return;
+
+	if (tcp_seq_cmp(tcp->snd_una + tx_len, tcp->snd_nxt) > 0)
+		tcp->snd_nxt = tcp->snd_una + tx_len;
+
+	tcp_send_packet_with_retry(tcp, TCP_ACK | TCP_PUSH,
+				   tcp->snd_una, tx_len, tx_offs);
+}
+
+static void tcp_stream_poll(struct tcp_stream *tcp, ulong time)
+{
+	ulong	delta;
+	void	(*handler)(struct tcp_stream *tcp);
+
+	if (tcp->state == TCP_CLOSED)
+		return;
+
+	/* handle rx inactivity timeout */
+	delta = msec_to_ticks(tcp->rx_inactiv_timeout);
+	if (time - tcp->time_last_rx >= delta) {
+		puts("\nTCP: rx inactivity timeout exceeded\n");
+		tcp_stream_reset(tcp);
+		tcp_stream_set_status(tcp, TCP_ERR_TOUT);
+		tcp_stream_destroy(tcp);
+		return;
+	}
+
+	/* handle retransmit timeout */
+	if ((tcp->time_handler != NULL) &&
+	    (time - tcp->time_start >= tcp->time_delta)) {
+		handler = tcp->time_handler;
+		tcp->time_handler = NULL;
+		handler(tcp);
+	}
+
+	tcp_steam_tx_try(tcp);
+}
+
+void tcp_streams_poll(void)
+{
+	ulong			time;
+	struct tcp_stream	*tcp;
+
+	time = get_timer(0);
+	tcp = &tcp_stream;
+	tcp_stream_poll(tcp, time);
 }
/**
@@ -300,18 +557,8 @@ int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int payload_len,
    		   "TCP Hdr:SYN (%pI4, %pI4, sq=%u, ak=%u)\n",
    		   &tcp->rhost, &net_ip,
    		   tcp_seq_num, tcp_ack_num);
-		tcp_activity_count = 0;
    	net_set_syn_options(tcp, b);
-		tcp_seq_num = 0;
-		tcp_ack_num = 0;
    	pkt_hdr_len = IP_TCP_O_SIZE;
-		if (tcp->state == TCP_SYN_SENT) {  /* Too many SYNs */
-			action = TCP_FIN;
-			tcp->state = TCP_FIN_WAIT_1;
-		} else {
-			tcp->lost.len = TCP_OPT_LEN_2;
-			tcp->state = TCP_SYN_SENT;
-		}
    	break;
    case TCP_SYN | TCP_ACK:
    case TCP_ACK:
@@ -328,21 +575,16 @@ int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int payload_len,
    		   &tcp->rhost, &net_ip, tcp_seq_num, tcp_ack_num);
    	payload_len = 0;
    	pkt_hdr_len = IP_TCP_HDR_SIZE;
-		tcp->state = TCP_FIN_WAIT_1;
    	break;
    case TCP_RST | TCP_ACK:
    case TCP_RST:
    	debug_cond(DEBUG_DEV_PKT,
    		   "TCP Hdr:RST  (%pI4, %pI4, s=%u, a=%u)\n",
    		   &tcp->rhost, &net_ip, tcp_seq_num, tcp_ack_num);
-		tcp->state = TCP_CLOSED;
    	break;
    /* Notify connection closing */
    case (TCP_FIN | TCP_ACK):
    case (TCP_FIN | TCP_ACK | TCP_PUSH):
-		if (tcp->state == TCP_CLOSE_WAIT)
-			tcp->state = TCP_CLOSING;
-
    	debug_cond(DEBUG_DEV_PKT,
    		   "TCP Hdr:FIN ACK PSH(%pI4, %pI4, s=%u, a=%u, A=%x)\n",
    		   &tcp->rhost, &net_ip,
@@ -382,7 +624,7 @@ int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int payload_len,
     * it is, then the u-boot tftp or nfs kernel netboot should be
     * considered.
     */
-	b->ip.hdr.tcp_win = htons(PKTBUFSRX * TCP_MSS >> TCP_SCALE);
+	b->ip.hdr.tcp_win = htons(tcp->rcv_wnd >> TCP_SCALE);
b->ip.hdr.tcp_xsum = 0;
    b->ip.hdr.tcp_ugr = 0;
@@ -501,6 +743,7 @@ void tcp_hole(struct tcp_stream *tcp, u32 tcp_seq_num, u32 len)
 void tcp_parse_options(struct tcp_stream *tcp, uchar *o, int o_len)
 {
    struct tcp_t_opt  *tsopt;
+	struct tcp_scale  *wsopt;
    uchar *p = o;
/*
@@ -515,10 +758,13 @@ void tcp_parse_options(struct tcp_stream *tcp, uchar *o, int o_len)
    	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_SCL:
+			wsopt = (struct tcp_scale *)p;
+			tcp->rmt_win_scale = wsopt->scale;
+			break;
    	case TCP_O_TS:
    		tsopt = (struct tcp_t_opt *)p;
    		tcp->rmt_timestamp = tsopt->t_snd;
@@ -533,129 +779,330 @@ void tcp_parse_options(struct tcp_stream *tcp, uchar *o, int o_len)
    }
 }
-static u8 tcp_state_machine(struct tcp_stream *tcp, u8 tcp_flags,
-			    u32 tcp_seq_num, int payload_len)
+static int tcp_seg_in_wnd(struct tcp_stream *tcp,
+			  u32 tcp_seq_num, int payload_len)
+{
+	if ((payload_len == 0) && (tcp->rcv_wnd == 0)) {
+		if (tcp_seq_num == tcp->rcv_nxt)
+			return 1;
+	}
+	if ((payload_len == 0) && (tcp->rcv_wnd > 0)) {
+		if ((tcp_seq_cmp(tcp->rcv_nxt, tcp_seq_num) <= 0) &&
+		    (tcp_seq_cmp(tcp_seq_num, tcp->rcv_nxt + tcp->rcv_wnd) < 0))
+			return 1;
+	}
+	if ((payload_len > 0) && (tcp->rcv_wnd > 0)) {
+		if ((tcp_seq_cmp(tcp->rcv_nxt, tcp_seq_num) <= 0) &&
+		    (tcp_seq_cmp(tcp_seq_num, tcp->rcv_nxt + tcp->rcv_wnd) < 0))
+			return 1;
+		tcp_seq_num += payload_len - 1;
+		if ((tcp_seq_cmp(tcp->rcv_nxt, tcp_seq_num) <= 0) &&
+		    (tcp_seq_cmp(tcp_seq_num, tcp->rcv_nxt + tcp->rcv_wnd) < 0))
+			return 1;
+	}
+	return 0;
+}
+
+static int tcp_rx_check_ack_num(struct tcp_stream *tcp, u32 tcp_seq_num,
+				u32 tcp_ack_num, u32 tcp_win_size)
+{
+	u32 old_offs, new_offs;
+	u8 action;
+
+	switch (tcp->state) {
+	case TCP_SYN_RECEIVED:
+		if ((tcp_seq_cmp(tcp->snd_una, tcp_ack_num) >= 0) ||
+		    (tcp_seq_cmp(tcp_ack_num, tcp->snd_nxt) > 0)) {
+			// segment acknowledgment is not acceptable
+			tcp_send_packet(tcp, TCP_RST, tcp_ack_num, 0, 0);
+			return TCP_PACKET_DROP;
+		}
+
+		tcp_stream_set_state(tcp, TCP_ESTABLISHED);
+		tcp->snd_wnd = tcp_win_size;
+		tcp->snd_wl1 = tcp_seq_num;
+		tcp->snd_wl2 = tcp_ack_num;
+
+		if (tcp->on_established != NULL)
+			tcp->on_established(tcp);
+
+		fallthrough;
+
+	case TCP_ESTABLISHED:
+	case TCP_FIN_WAIT_1:
+	case TCP_FIN_WAIT_2:
+	case TCP_CLOSE_WAIT:
+	case TCP_CLOSING:
+		if (tcp_seq_cmp(tcp_ack_num, tcp->snd_nxt) > 0) {
+			// ACK acks something not yet sent
+			action = tcp_stream_fin_needed(tcp, tcp->snd_una) | TCP_ACK;
+			tcp_send_packet(tcp, action, tcp->snd_una, tcp->rcv_nxt, 0);
+			return TCP_PACKET_DROP;
+		}
+
+		if (tcp_seq_cmp(tcp->snd_una, tcp_ack_num) < 0) {
+			old_offs = tcp_stream_tx_offs(tcp);
+			tcp->snd_una = tcp_ack_num;
+			new_offs = tcp_stream_tx_offs(tcp);
+			if ((tcp->time_handler != NULL) &&
+			    (tcp_seq_cmp(tcp->snd_una, tcp->retry_seq_num) > 0)) {
+				tcp_stream_set_time_handler(tcp, 0, NULL);
+			}
+			if ((tcp->on_snd_una_update != NULL) &&
+			    (old_offs != new_offs))
+				tcp->on_snd_una_update(tcp, new_offs);
+		}
+
+		if (tcp_seq_cmp(tcp->snd_una, tcp_ack_num) <= 0) {
+			if ((tcp_seq_cmp(tcp->snd_wl1, tcp_seq_num) < 0) ||
+			    ((tcp->snd_wl1 == tcp_seq_num) &&
+			     (tcp_seq_cmp(tcp->snd_wl2, tcp_seq_num) <= 0))) {
+				tcp->snd_wnd = tcp_win_size;
+				tcp->snd_wl1 = tcp_seq_num;
+				tcp->snd_wl2 = tcp_ack_num;
+			}
+		}
+
+		if (tcp->state == TCP_FIN_WAIT_1) {
+			if (tcp->snd_una == tcp->snd_nxt)
+				tcp_stream_set_state(tcp, TCP_FIN_WAIT_2);
+		}
+
+		if (tcp->state == TCP_CLOSING) {
+			if (tcp->snd_una == tcp->snd_nxt)
+				tcp_stream_set_state(tcp, TCP_CLOSED);
+		}
+		return TCP_PACKET_OK;
+
+	case TCP_LAST_ACK:
+		if (tcp_ack_num == tcp->snd_nxt)
+			tcp_stream_set_state(tcp, TCP_CLOSED);
+		return TCP_PACKET_OK;
+
+	default:
+		return TCP_PACKET_DROP;
+	}
+}
+
+static int tcp_rx_user_data(struct tcp_stream *tcp, u32 tcp_seq_num,
+			    char *buf, int 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;
+	u32 tmp_len, buf_offs, old_offs, new_offs;
+	u8 action;
+	if (len == 0)
+		return TCP_PACKET_OK;
+
+	switch (tcp->state) {
+	case TCP_ESTABLISHED:
+	case TCP_FIN_WAIT_1:
+	case TCP_FIN_WAIT_2:
+		break;
+	default:
+		return TCP_PACKET_DROP;
+	}
+
+	tmp_len = len;
+	old_offs = tcp_stream_rx_offs(tcp);
+	buf_offs = tcp_seq_num - tcp->irs - 1;
+	if (tcp->rx != NULL)
+		tmp_len = tcp->rx(tcp, buf_offs, buf, len);
+	if (tmp_len)
+		tcp_hole(tcp, tcp_seq_num, tmp_len);
+
+	new_offs = tcp_stream_rx_offs(tcp);
+	if ((tcp->on_rcv_nxt_update != NULL) && (old_offs != new_offs))
+		tcp->on_rcv_nxt_update(tcp, new_offs);
+
+	action = tcp_stream_fin_needed(tcp, tcp->snd_una) | TCP_ACK;
+	tcp_send_packet(tcp, action, tcp->snd_una, tcp->rcv_nxt, 0);
+	return TCP_PACKET_OK;
+}
+
+void tcp_rx_state_machine(struct tcp_stream *tcp,
+			  union tcp_build_pkt *b, unsigned int pkt_len)
+{
+	int tcp_len = pkt_len - IP_HDR_SIZE;
+	u32 tcp_seq_num, tcp_ack_num, tcp_win_size;
+	int tcp_hdr_len, payload_len;
+	u8  tcp_flags, action;
+
+	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(tcp, (uchar *)b + IP_TCP_HDR_SIZE,
+				  tcp_hdr_len - TCP_HDR_SIZE);
    /*
-	 * 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.
+	 * Incoming sequence and ack numbers are server's view of the numbers.
+	 * The app must swap the numbers when responding.
     */
-	debug_cond(DEBUG_INT_STATE, "TCP STATE ENTRY %x\n", action);
-	if (tcp_rst) {
-		action = TCP_DATA;
-		tcp->state = TCP_CLOSED;
-		net_set_state(NETLOOP_FAIL);
-		debug_cond(DEBUG_INT_STATE, "TCP Reset %x\n", tcp_flags);
-		return TCP_RST;
-	}
+	tcp_seq_num = ntohl(b->ip.hdr.tcp_seq);
+	tcp_ack_num = ntohl(b->ip.hdr.tcp_ack);
+	tcp_win_size = ntohs(b->ip.hdr.tcp_win) << tcp->rmt_win_scale;
+
+	tcp_flags = b->ip.hdr.tcp_flags;
-	switch  (tcp->state) {
+//	printf("pkt: seq=%d, ack=%d, flags=%x, len=%d\n",
+//		tcp_seq_num - tcp->irs, tcp_ack_num - tcp->iss, tcp_flags, pkt_len);
+//	printf("tcp: rcv_nxt=%d, snd_una=%d, snd_nxt=%d\n\n",
+//		tcp->rcv_nxt - tcp->irs, tcp->snd_una - tcp->iss, tcp->snd_nxt - tcp->iss);
+
+	switch (tcp->state) {
    case TCP_CLOSED:
-		debug_cond(DEBUG_INT_STATE, "TCP CLOSED %x\n", tcp_flags);
-		if (tcp_syn) {
-			action = TCP_SYN | TCP_ACK;
-			tcp->irs = tcp_seq_num;
-			tcp->rcv_nxt = tcp_seq_num + 1;
-			tcp->lost.len = TCP_OPT_LEN_2;
-			tcp->state = TCP_SYN_RECEIVED;
-		} else if (tcp_ack || tcp_fin) {
-			action = TCP_DATA;
+		if (tcp_flags & TCP_RST)
+			return;
+
+		if (tcp_flags & TCP_ACK) {
+			tcp_send_packet(tcp, TCP_RST, tcp_ack_num, 0, 0);
+			return;
    	}
-		break;
-	case TCP_SYN_RECEIVED:
+
+		if (!(tcp_flags & TCP_SYN))
+			return;
+
+		tcp->irs = tcp_seq_num;
+		tcp->rcv_nxt = tcp->irs + 1;
+
+		tcp->iss = tcp_get_start_seq();
+		tcp->snd_una = tcp->iss;
+		tcp->snd_nxt = tcp->iss + 1;
+		tcp->snd_wnd = tcp_win_size;
+
+		tcp->time_last_rx = get_timer(0);
+
+		tcp_stream_set_state(tcp, TCP_SYN_RECEIVED);
+		tcp_send_packet_with_retry(tcp, TCP_SYN | TCP_ACK,
+					   tcp->iss, 0, 0);
+		return;
+
    case TCP_SYN_SENT:
-		debug_cond(DEBUG_INT_STATE, "TCP_SYN_SENT | TCP_SYN_RECEIVED %x, %u\n",
-			   tcp_flags, tcp_seq_num);
-		if (tcp_fin) {
-			action = action | TCP_PUSH;
-			tcp->state = TCP_CLOSE_WAIT;
-		} else if (tcp_ack || (tcp_syn && tcp_ack)) {
-			action |= TCP_ACK;
-			tcp->irs = tcp_seq_num;
-			tcp->rcv_nxt = tcp_seq_num + 1;
-			tcp->state = TCP_ESTABLISHED;
-
-			if (tcp_syn && tcp_ack)
-				action |= TCP_PUSH;
-		} else {
-			action = TCP_DATA;
+		if (!(tcp_flags & TCP_ACK))
+			return;
+
+		if ((tcp_seq_cmp(tcp_ack_num, tcp->iss) <= 0) ||
+		    (tcp_seq_cmp(tcp_ack_num, tcp->snd_nxt) > 0)) {
+			if (!(tcp_flags & TCP_RST))
+				tcp_send_packet(tcp, TCP_RST, tcp_ack_num, 0, 0);
+			return;
    	}
-		break;
+
+		if (tcp_flags & TCP_RST) {
+			tcp_stream_set_status(tcp, TCP_ERR_RST);
+			tcp_stream_set_state(tcp, TCP_CLOSED);
+			return;
+		}
+
+		if (!(tcp_flags & TCP_SYN))
+			return;
+
+		/* stop retransmit of SYN */
+		tcp_stream_set_time_handler(tcp, 0, NULL);
+
+		tcp->irs = tcp_seq_num;
+		tcp->rcv_nxt = tcp->irs + 1;
+		tcp->snd_una = tcp_ack_num;
+
+		tcp->time_last_rx = get_timer(0);
+
+		/* our SYN has been ACKed */
+		tcp_stream_set_state(tcp, TCP_ESTABLISHED);
+
+		if (tcp->on_established != NULL)
+			tcp->on_established(tcp);
+
+		action = tcp_stream_fin_needed(tcp, tcp->snd_una) | TCP_ACK;
+		tcp_send_packet(tcp, action, tcp->snd_una, tcp->rcv_nxt, 0);
+		tcp_rx_user_data(tcp, tcp_seq_num,
+				 ((char *)b) + pkt_len - payload_len,
+				 payload_len);
+		return;
+
+	case TCP_SYN_RECEIVED:
    case TCP_ESTABLISHED:
-		debug_cond(DEBUG_INT_STATE, "TCP_ESTABLISHED %x\n", tcp_flags);
-		if (payload_len > 0) {
-			tcp_hole(tcp, tcp_seq_num, payload_len);
-			tcp_fin = TCP_DATA;  /* cause standalone FIN */
+	case TCP_FIN_WAIT_1:
+	case TCP_FIN_WAIT_2:
+	case TCP_CLOSE_WAIT:
+	case TCP_CLOSING:
+	case TCP_LAST_ACK:
+		if (!tcp_seg_in_wnd(tcp, tcp_seq_num, payload_len)) {
+			if (tcp_flags & TCP_RST)
+				return;
+			action = tcp_stream_fin_needed(tcp, tcp->snd_una) | TCP_ACK;
+			tcp_send_packet(tcp, action, tcp->snd_una, tcp->rcv_nxt, 0);
+			return;
    	}
-		if ((tcp_fin) &&
-		    (!IS_ENABLED(CONFIG_PROT_TCP_SACK) ||
-		     tcp->lost.len <= TCP_OPT_LEN_2)) {
-			action = action | TCP_FIN | TCP_PUSH | TCP_ACK;
-			tcp->state = TCP_CLOSE_WAIT;
-		} else if (tcp_ack) {
-			action = TCP_DATA;
+		tcp->time_last_rx = get_timer(0);
+
+		if (tcp_flags & TCP_RST) {
+			tcp_stream_set_status(tcp, TCP_ERR_RST);
+			tcp_stream_set_state(tcp, TCP_CLOSED);
+			return;
    	}
-		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;
-			tcp->state = TCP_CLOSED;
-			puts("\n");
-		} else if (tcp_syn) {
-			action = TCP_DATA;
-		} else if (tcp_fin) {
-			action = TCP_DATA;
+		if (tcp_flags & TCP_SYN) {
+			tcp_send_packet(tcp, TCP_RST, tcp_ack_num, 0, 0);
+			tcp_stream_set_status(tcp, TCP_ERR_RST);
+			tcp_stream_set_state(tcp, TCP_CLOSED);
+			return;
    	}
-		break;
-	case TCP_FIN_WAIT_1:
-		debug_cond(DEBUG_INT_STATE, "TCP_FIN_WAIT_1 (%x)\n", tcp_flags);
-		if (tcp_fin) {
-			tcp->rcv_nxt++;
-			action = TCP_ACK | TCP_FIN;
-			tcp->state = TCP_FIN_WAIT_2;
+
+		if (!(tcp_flags & TCP_ACK))
+			return;
+
+		if (tcp_rx_check_ack_num(tcp, tcp_seq_num, tcp_ack_num,
+					 tcp_win_size) == TCP_PACKET_DROP) {
+			return;
    	}
-		if (tcp_syn)
-			action = TCP_RST;
-		if (tcp_ack)
-			tcp->state = TCP_CLOSED;
-		break;
-	case TCP_CLOSING:
-		debug_cond(DEBUG_INT_STATE, "TCP_CLOSING (%x)\n", tcp_flags);
-		if (tcp_ack) {
-			action = TCP_PUSH;
-			tcp->state = TCP_CLOSED;
-			puts("\n");
-		} else if (tcp_syn) {
-			action = TCP_RST;
-		} else if (tcp_fin) {
-			action = TCP_DATA;
+
+		if (tcp_rx_user_data(tcp, tcp_seq_num,
+				     ((char *)b) + pkt_len - payload_len,
+				     payload_len) == TCP_PACKET_DROP) {
+			return;
+		}
+
+		if (tcp_flags & TCP_FIN) {
+			tcp->fin_rx = 1;
+			tcp->fin_rx_seq = tcp_seq_num + payload_len + 1;
+			tcp_hole(tcp, tcp_seq_num + payload_len, 1);
+			action = tcp_stream_fin_needed(tcp, tcp->snd_una) | TCP_ACK;
+			tcp_send_packet(tcp, action, tcp->snd_una, tcp->rcv_nxt, 0);
+		}
+
+		if (tcp->fin_rx && (tcp->fin_rx_seq == tcp->rcv_nxt)) {
+			/* all rx data were processed */
+			switch (tcp->state) {
+			case TCP_ESTABLISHED:
+				tcp_stream_set_state(tcp, TCP_LAST_ACK);
+				tcp_send_packet_with_retry(tcp, TCP_ACK | TCP_FIN,
+							   tcp->snd_nxt, 0, 0);
+				tcp->snd_nxt++;
+				break;
+
+			case TCP_FIN_WAIT_1:
+				if (tcp_ack_num == tcp->snd_nxt)
+					tcp_stream_set_state(tcp, TCP_CLOSED);
+				else
+					tcp_stream_set_state(tcp, TCP_CLOSING);
+				break;
+
+			case TCP_FIN_WAIT_2:
+				tcp_stream_set_state(tcp, TCP_CLOSED);
+				break;
+
+			default:
+				break;
+			}
+		}
+
+		if ((tcp->state == TCP_FIN_WAIT_1) &&
+		    tcp_stream_fin_needed(tcp, tcp->snd_una)) {
+			/* all tx data were acknowledged */
+			tcp_send_packet_with_retry(tcp, TCP_ACK | TCP_FIN,
+						   tcp->snd_una, 0, 0);
    	}
-		break;
    }
-	return action;
 }
/**
@@ -667,9 +1114,6 @@ 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;
-	int tcp_hdr_len, payload_len;
    struct tcp_stream *tcp;
    struct in_addr src;
@@ -713,54 +1157,57 @@ void rxhand_tcp_f(union tcp_build_pkt *b, unsigned int pkt_len)
    if (!tcp)
    	return;
-	tcp_hdr_len = GET_TCP_HDR_LEN_IN_BYTES(b->ip.hdr.tcp_hlen);
-	payload_len = tcp_len - tcp_hdr_len;
+	tcp_rx_state_machine(tcp, b, pkt_len);
+	tcp_stream_put(tcp);
+}
-	if (tcp_hdr_len > TCP_HDR_SIZE)
-		tcp_parse_options(tcp, (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);
+struct tcp_stream *tcp_stream_connect(struct in_addr rhost, u16 rport)
+{
+	struct tcp_stream *tcp;
-	/* Packets are not ordered. Send to app as received. */
-	tcp_action = tcp_state_machine(tcp, b->ip.hdr.tcp_flags,
-				       tcp_seq_num, payload_len);
+	tcp = tcp_stream_add(rhost, rport, random_port());
+	if (tcp == NULL)
+		return NULL;
-	tcp_activity_count++;
-	if (tcp_activity_count > TCP_ACTIVITY) {
-		puts("| ");
-		tcp_activity_count = 0;
-	}
+	tcp->iss = tcp_get_start_seq();
+	tcp->snd_una = tcp->iss;
+	tcp->snd_nxt = tcp->iss + 1;
-	if ((tcp_action & TCP_PUSH) || payload_len > 0) {
-		debug_cond(DEBUG_DEV_PKT,
-			   "TCP Notify (action=%x, Seq=%u,Ack=%u,Pay%d)\n",
-			   tcp_action, tcp_seq_num, tcp_ack_num, payload_len);
+	tcp_stream_set_state(tcp, TCP_SYN_SENT);
+	tcp_send_packet_with_retry(tcp, TCP_SYN, tcp->snd_una, 0, 0);
+	return tcp;
+}
-		(*tcp_packet_handler) (tcp, (uchar *)b + pkt_len - payload_len,
-				       tcp_seq_num, tcp_ack_num, tcp_action,
-				       payload_len);
+void tcp_stream_reset(struct tcp_stream *tcp)
+{
+	if (tcp->state == TCP_CLOSED)
+		return;
-	} else if (tcp_action != TCP_DATA) {
-		debug_cond(DEBUG_DEV_PKT,
-			   "TCP Action (action=%x,Seq=%u,Ack=%u,Pay=%d)\n",
-			   tcp_action, tcp_ack_num, tcp->rcv_nxt, payload_len);
-
-		/*
-		 * Warning: Incoming Ack & Seq sequence numbers are transposed
-		 * here to outgoing Seq & Ack sequence numbers
-		 */
-		net_send_tcp_packet(0, tcp->rhost, tcp->rport, tcp->lport,
-				    (tcp_action & (~TCP_PUSH)),
-				    tcp_ack_num, tcp->rcv_nxt);
-	}
+	tcp_stream_set_time_handler(tcp, 0, NULL);
+	tcp_send_packet(tcp, TCP_RST, tcp->snd_una, 0, 0);
+	tcp_stream_set_status(tcp, TCP_ERR_RST);
+	tcp_stream_set_state(tcp, TCP_CLOSED);
 }
-struct tcp_stream *tcp_stream_connect(struct in_addr rhost, u16 rport)
+void tcp_stream_close(struct tcp_stream *tcp)
 {
-	return tcp_stream_add(rhost, rport, random_port());
+	switch (tcp->state) {
+	case TCP_SYN_SENT:
+		tcp_stream_reset(tcp);
+		break;
+	case TCP_SYN_RECEIVED:
+	case TCP_ESTABLISHED:
+		tcp->fin_tx = 1;
+		tcp->fin_tx_seq = tcp->snd_nxt;
+		if (tcp_stream_fin_needed(tcp, tcp->snd_una)) {
+			/* all tx data were acknowledged */
+			tcp_send_packet_with_retry(tcp, TCP_ACK | TCP_FIN,
+						   tcp->snd_una, 0, 0);
+		}
+		tcp_stream_set_state(tcp, TCP_FIN_WAIT_1);
+		tcp->snd_nxt++;
+		break;
+	default:
+		break;
+	}
 }
diff --git a/net/wget.c b/net/wget.c
index ad5db21e97e..ba95efa61c1 100644
--- a/net/wget.c
+++ b/net/wget.c
@@ -21,48 +21,26 @@ DECLARE_GLOBAL_DATA_PTR;
 /* The default, change with environment variable 'httpdstp' */
 #define SERVER_PORT		80
+#define HASHES_PER_LINE		65
+
+#define HTTP_MAX_HDR_LEN	2048
+
 static const char bootfile1[] = "GET ";
 static const char bootfile3[] = " HTTP/1.0\r\n\r\n";
 static const char http_eom[] = "\r\n\r\n";
-static const char http_ok[] = "200";
-static const char content_len[] = "Content-Length";
+static const char http_ok[] = " 200 ";
+static const char content_len[] = "Content-Length:";
 static const char linefeed[] = "\r\n";
-static int wget_timeout_count;
-struct tcp_stream *tcp;
-
-struct pkt_qd {
-	uchar *pkt;
-	unsigned int tcp_seq_num;
-	unsigned int len;
-};
-
-/*
- * This is a control structure for out of order packets received.
- * The actual packet bufers are in the kernel space, and are
- * expected to be overwritten by the downloaded image.
- */
-#define PKTQ_SZ (PKTBUFSRX / 4)
-static struct pkt_qd pkt_q[PKTQ_SZ];
-static int pkt_q_idx;
+static struct in_addr web_server_ip;
+static unsigned int server_port;
 static unsigned long content_length;
 static unsigned int packets;
-
-static unsigned int initial_data_seq_num;
-static unsigned int next_data_seq_num;
-
-static enum  wget_state current_wget_state;
+static u32 http_hdr_size;
+static int wget_tsize_num_hash;
static char *image_url;
-static unsigned int wget_timeout = WGET_TIMEOUT;
-
 static enum net_loop_state wget_loop_state;
-/* Timeout retry parameters */
-static u8 retry_action;			/* actions for TCP retry */
-static unsigned int retry_tcp_ack_num;	/* TCP retry acknowledge number*/
-static unsigned int retry_tcp_seq_num;	/* TCP retry sequence number */
-static int retry_len;			/* TCP retry length */
-
 static ulong wget_load_size;
/**
@@ -95,7 +73,6 @@ static int wget_init_load_size(void)
 static inline int store_block(uchar *src, unsigned int offset, unsigned int len)
 {
    ulong store_addr = image_load_addr + offset;
-	ulong newsize = offset + len;
    uchar *ptr;
if (IS_ENABLED(CONFIG_LMB)) {
@@ -115,330 +92,150 @@ static inline int store_block(uchar *src, unsigned int offset, unsigned int len)
    ptr = map_sysmem(store_addr, len);
    memcpy(ptr, src, len);
    unmap_sysmem(ptr);
-
-	if (net_boot_file_size < (offset + len))
-		net_boot_file_size = newsize;
-
    return 0;
 }
-/**
- * wget_send_stored() - wget response dispatcher
- *
- * WARNING, This, and only this, is the place in wget.c where
- * SEQUENCE NUMBERS are swapped between incoming (RX)
- * and outgoing (TX).
- * Procedure wget_handler() is correct for RX traffic.
- */
-static void wget_send_stored(void)
+static void show_block_marker(void)
 {
-	u8 action = retry_action;
-	int len = retry_len;
-	unsigned int tcp_ack_num = retry_tcp_seq_num + (len == 0 ? 1 : len);
-	unsigned int tcp_seq_num = retry_tcp_ack_num;
-	uchar *ptr, *offset;
-
-	switch (current_wget_state) {
-	case WGET_CLOSED:
-		debug_cond(DEBUG_WGET, "wget: send SYN\n");
-		current_wget_state = WGET_CONNECTING;
-		net_send_tcp_packet(0, tcp->rhost, tcp->rport, tcp->lport, action,
-				    tcp_seq_num, tcp_ack_num);
-		packets = 0;
-		break;
-	case WGET_CONNECTING:
-		pkt_q_idx = 0;
-		net_send_tcp_packet(0, tcp->rhost, tcp->rport, tcp->lport, action,
-				    tcp_seq_num, tcp_ack_num);
-
-		ptr = net_tx_packet + net_eth_hdr_size() +
-			IP_TCP_HDR_SIZE + TCP_TSOPT_SIZE + 2;
-		offset = ptr;
-
-		memcpy(offset, &bootfile1, strlen(bootfile1));
-		offset += strlen(bootfile1);
-
-		memcpy(offset, image_url, strlen(image_url));
-		offset += strlen(image_url);
-
-		memcpy(offset, &bootfile3, strlen(bootfile3));
-		offset += strlen(bootfile3);
-		net_send_tcp_packet((offset - ptr), tcp->rhost, tcp->rport, tcp->lport,
-				    TCP_PUSH, tcp_seq_num, tcp_ack_num);
-		current_wget_state = WGET_CONNECTED;
-		break;
-	case WGET_CONNECTED:
-	case WGET_TRANSFERRING:
-	case WGET_TRANSFERRED:
-		net_send_tcp_packet(0, tcp->rhost, tcp->rport, tcp->lport, action,
-				    tcp_seq_num, tcp_ack_num);
-		break;
-	}
-}
+	int cnt;
-static void wget_send(u8 action, unsigned int tcp_seq_num,
-		      unsigned int tcp_ack_num, int len)
-{
-	retry_action = action;
-	retry_tcp_ack_num = tcp_ack_num;
-	retry_tcp_seq_num = tcp_seq_num;
-	retry_len = len;
+	if (content_length != -1) {
+		if (net_boot_file_size > content_length)
+			content_length = net_boot_file_size;
-	wget_send_stored();
+		cnt = net_boot_file_size * 50 / content_length;
+		while (wget_tsize_num_hash < cnt) {
+			putc('#');
+			wget_tsize_num_hash++;
+		}
+	} else {
+		if ((packets % 10) == 0)
+			putc('#');
+		else if (((packets + 1) % (10 * HASHES_PER_LINE)) == 0)
+			puts("\n");
+	}
 }
-void wget_fail(char *error_message, unsigned int tcp_seq_num,
-	       unsigned int tcp_ack_num, u8 action)
+static void tcp_stream_on_closed(struct tcp_stream *tcp)
 {
-	printf("wget: Transfer Fail - %s\n", error_message);
-	net_set_timeout_handler(0, NULL);
-	wget_send(action, tcp_seq_num, tcp_ack_num, 0);
+	if (tcp->status != TCP_ERR_OK)
+		wget_loop_state = NETLOOP_FAIL;
+
+	if (wget_loop_state != NETLOOP_SUCCESS)
+		printf("\nwget: Transfer Fail, TCP status - %d\n", tcp->status);
+	else
+		printf("\nPackets received %d, Transfer Successful\n", packets);
+	net_set_state(wget_loop_state);
 }
-void wget_success(u8 action, unsigned int tcp_seq_num,
-		  unsigned int tcp_ack_num, int len, int packets)
+static void tcp_stream_on_rcv_nxt_update(struct tcp_stream *tcp, u32 rx_bytes)
 {
-	printf("Packets received %d, Transfer Successful\n", packets);
-	wget_send(action, tcp_seq_num, tcp_ack_num, len);
-}
+	char	*pos, *tail;
+	uchar	saved, *ptr;
+	int i;
-/*
- * Interfaces of U-BOOT
- */
-static void wget_timeout_handler(void)
-{
-	if (++wget_timeout_count > WGET_RETRY_COUNT) {
-		puts("\nRetry count exceeded; starting again\n");
-		wget_send(TCP_RST, 0, 0, 0);
-		net_start_again();
-	} else {
-		puts("T ");
-		net_set_timeout_handler(wget_timeout +
-					WGET_TIMEOUT * wget_timeout_count,
-					wget_timeout_handler);
-		wget_send_stored();
+	if (http_hdr_size != 0) {
+		net_boot_file_size = rx_bytes - http_hdr_size;
+		show_block_marker();
+		return;
    }
-}
-#define PKT_QUEUE_OFFSET 0x20000
-#define PKT_QUEUE_PACKET_SIZE 0x800
+	ptr = map_sysmem(image_load_addr, rx_bytes + 1);
-static void wget_connected(uchar *pkt, unsigned int tcp_seq_num,
-			   u8 action, unsigned int tcp_ack_num, unsigned int len)
-{
-	uchar *pkt_in_q;
-	char *pos;
-	int hlen, i;
-	uchar *ptr1;
+	saved = ptr[rx_bytes];
+	ptr[rx_bytes] = '\0';
+	pos = strstr((char *)ptr, http_eom);
+	ptr[rx_bytes] = saved;
-	pkt[len] = '\0';
-	pos = strstr((char *)pkt, http_eom);
+	if (pos == NULL) {
+		if ((rx_bytes < HTTP_MAX_HDR_LEN) &&
+		    (tcp->state == TCP_ESTABLISHED))
+			goto end;
-	if (!pos) {
-		debug_cond(DEBUG_WGET,
-			   "wget: Connected, data before Header %p\n", pkt);
-		pkt_in_q = (void *)image_load_addr + PKT_QUEUE_OFFSET +
-			(pkt_q_idx * PKT_QUEUE_PACKET_SIZE);
-
-		ptr1 = map_sysmem((phys_addr_t)pkt_in_q, len);
-		memcpy(ptr1, pkt, len);
-		unmap_sysmem(ptr1);
-
-		pkt_q[pkt_q_idx].pkt = pkt_in_q;
-		pkt_q[pkt_q_idx].tcp_seq_num = tcp_seq_num;
-		pkt_q[pkt_q_idx].len = len;
-		pkt_q_idx++;
-
-		if (pkt_q_idx >= PKTQ_SZ) {
-			printf("wget: Fatal error, queue overrun!\n");
-			net_set_state(NETLOOP_FAIL);
+		printf("ERROR: misssed HTTP header\n");
+		tcp_stream_close(tcp);
+		wget_loop_state = NETLOOP_FAIL;
+		goto end;
+	}
-			return;
-		}
-	} else {
-		debug_cond(DEBUG_WGET, "wget: Connected HTTP Header %p\n", pkt);
-		/* sizeof(http_eom) - 1 is the string length of (http_eom) */
-		hlen = pos - (char *)pkt + sizeof(http_eom) - 1;
-		pos = strstr((char *)pkt, linefeed);
-		if (pos > 0)
-			i = pos - (char *)pkt;
-		else
-			i = hlen;
-		printf("%.*s", i,  pkt);
-
-		current_wget_state = WGET_TRANSFERRING;
-
-		initial_data_seq_num = tcp_seq_num + hlen;
-		next_data_seq_num    = tcp_seq_num + len;
-
-		if (strstr((char *)pkt, http_ok) == 0) {
-			debug_cond(DEBUG_WGET,
-				   "wget: Connected Bad Xfer\n");
-			wget_loop_state = NETLOOP_FAIL;
-			wget_send(action, tcp_seq_num, tcp_ack_num, len);
-		} else {
-			debug_cond(DEBUG_WGET,
-				   "wget: Connctd pkt %p  hlen %x\n",
-				   pkt, hlen);
-
-			pos = strstr((char *)pkt, content_len);
-			if (!pos) {
-				content_length = -1;
-			} else {
-				pos += sizeof(content_len) + 2;
-				strict_strtoul(pos, 10, &content_length);
-				debug_cond(DEBUG_WGET,
-					   "wget: Connected Len %lu\n",
-					   content_length);
-			}
-
-			net_boot_file_size = 0;
-
-			if (len > hlen) {
-				if (store_block(pkt + hlen, 0, len - hlen) != 0) {
-					wget_loop_state = NETLOOP_FAIL;
-					wget_fail("wget: store error\n", tcp_seq_num, tcp_ack_num, action);
-					net_set_state(NETLOOP_FAIL);
-					return;
-				}
-			}
+	http_hdr_size = pos - (char *)ptr + strlen(http_eom);
+	*pos = '\0';
+
+	pos = strstr((char *)ptr, linefeed);
+	if (pos > 0)
+		i = pos - (char *)ptr;
+	else
+		i = http_hdr_size - strlen(http_eom);
+	printf("%.*s\n", i,  ptr);
+
+	if (strstr((char *)ptr, http_ok) == NULL) {
+		debug_cond(DEBUG_WGET, "wget: Connected Bad Xfer\n");
+		tcp_stream_close(tcp);
+		wget_loop_state = NETLOOP_FAIL;
+		goto end;
+	}
-			debug_cond(DEBUG_WGET,
-				   "wget: Connected Pkt %p hlen %x\n",
-				   pkt, hlen);
-
-			for (i = 0; i < pkt_q_idx; i++) {
-				int err;
-
-				ptr1 = map_sysmem(
-					(phys_addr_t)(pkt_q[i].pkt),
-					pkt_q[i].len);
-				err = store_block(ptr1,
-					  pkt_q[i].tcp_seq_num -
-					  initial_data_seq_num,
-					  pkt_q[i].len);
-				unmap_sysmem(ptr1);
-				debug_cond(DEBUG_WGET,
-					   "wget: Connctd pkt Q %p len %x\n",
-					   pkt_q[i].pkt, pkt_q[i].len);
-				if (err) {
-					wget_loop_state = NETLOOP_FAIL;
-					wget_fail("wget: store error\n", tcp_seq_num, tcp_ack_num, action);
-					net_set_state(NETLOOP_FAIL);
-					return;
-				}
-			}
-		}
+	debug_cond(DEBUG_WGET, "wget: Connctd pkt %p  hlen %x\n",
+		   ptr, http_hdr_size);
+
+	pos = strstr((char *)ptr, content_len);
+	if (!pos) {
+		content_length = -1;
+	} else {
+		pos += strlen(content_len) + 1;
+		content_length = simple_strtoul(pos, &tail, 10);
+		if ((*tail != '\r') && (*tail != '\n') && (*tail != '\0'))
+			content_length = -1;
+		printf("%s %d\n", content_len, (int)content_length);
    }
-	wget_send(action, tcp_seq_num, tcp_ack_num, len);
+
+	net_boot_file_size = rx_bytes - http_hdr_size;
+	memmove(ptr, ptr + http_hdr_size, net_boot_file_size);
+
+end:
+	unmap_sysmem(ptr);
+
+	wget_loop_state = NETLOOP_SUCCESS;
 }
-/**
- * wget_handler() - TCP handler of wget
- * @tcp: TCP stream
- * @pkt: pointer to the application packet
- * @tcp_seq_num: TCP sequential number
- * @tcp_ack_num: TCP acknowledgment number
- * @action: TCP action (SYN, ACK, FIN, etc)
- * @len: packet length
- *
- * In the "application push" invocation, the TCP header with all
- * its information is pointed to by the packet pointer.
- */
-static void wget_handler(struct tcp_stream *tcp, uchar *pkt,
-			 u32 tcp_seq_num, u32 tcp_ack_num,
-			 u8 action, unsigned int len)
+static u32 tcp_stream_rx(struct tcp_stream *tcp, u32 rx_offs, void *buf, u32 len)
 {
-	enum tcp_state wget_tcp_state = tcp_stream_get_state(tcp);
-
-	net_set_timeout_handler(wget_timeout, wget_timeout_handler);
    packets++;
+	store_block(buf, rx_offs - http_hdr_size, len);
+	return len;
+}
-	switch (current_wget_state) {
-	case WGET_CLOSED:
-		debug_cond(DEBUG_WGET, "wget: Handler: Error!, State wrong\n");
-		break;
-	case WGET_CONNECTING:
-		debug_cond(DEBUG_WGET,
-			   "wget: Connecting In len=%x, Seq=%u, Ack=%u\n",
-			   len, tcp_seq_num, tcp_ack_num);
-		if (!len) {
-			if (wget_tcp_state == TCP_ESTABLISHED) {
-				debug_cond(DEBUG_WGET,
-					   "wget: Cting, send, len=%x\n", len);
-				wget_send(action, tcp_seq_num, tcp_ack_num,
-					  len);
-			} else {
-				printf("%.*s", len,  pkt);
-				wget_fail("wget: Handler Connected Fail\n",
-					  tcp_seq_num, tcp_ack_num, action);
-			}
-		}
-		break;
-	case WGET_CONNECTED:
-		debug_cond(DEBUG_WGET, "wget: Connected seq=%u, len=%x\n",
-			   tcp_seq_num, len);
-		if (!len) {
-			wget_fail("Image not found, no data returned\n",
-				  tcp_seq_num, tcp_ack_num, action);
-		} else {
-			wget_connected(pkt, tcp_seq_num, action, tcp_ack_num, len);
-		}
-		break;
-	case WGET_TRANSFERRING:
-		debug_cond(DEBUG_WGET,
-			   "wget: Transferring, seq=%x, ack=%x,len=%x\n",
-			   tcp_seq_num, tcp_ack_num, len);
-
-		if (next_data_seq_num != tcp_seq_num) {
-			debug_cond(DEBUG_WGET, "wget: seq=%x packet was lost\n", next_data_seq_num);
-			return;
-		}
-		next_data_seq_num = tcp_seq_num + len;
+static u32 tcp_stream_tx(struct tcp_stream *tcp, u32 tx_offs, void *buf, u32 maxlen)
+{
+	int ret;
-		if (store_block(pkt, tcp_seq_num - initial_data_seq_num, len) != 0) {
-			wget_fail("wget: store error\n",
-				  tcp_seq_num, tcp_ack_num, action);
-			net_set_state(NETLOOP_FAIL);
-			return;
-		}
+	if (tx_offs != 0)
+		return 0;
-		switch (wget_tcp_state) {
-		case TCP_FIN_WAIT_2:
-			wget_send(TCP_ACK, tcp_seq_num, tcp_ack_num, len);
-			fallthrough;
-		case TCP_SYN_SENT:
-		case TCP_SYN_RECEIVED:
-		case TCP_CLOSING:
-		case TCP_FIN_WAIT_1:
-		case TCP_CLOSED:
-			net_set_state(NETLOOP_FAIL);
-			break;
-		case TCP_ESTABLISHED:
-			wget_send(TCP_ACK, tcp_seq_num, tcp_ack_num,
-				  len);
-			wget_loop_state = NETLOOP_SUCCESS;
-			break;
-		case TCP_CLOSE_WAIT:     /* End of transfer */
-			current_wget_state = WGET_TRANSFERRED;
-			wget_send(action | TCP_ACK | TCP_FIN,
-				  tcp_seq_num, tcp_ack_num, len);
-			break;
-		}
-		break;
-	case WGET_TRANSFERRED:
-		printf("Packets received %d, Transfer Successful\n", packets);
-		net_set_state(wget_loop_state);
-		break;
-	}
+	ret = snprintf(buf, maxlen, "%s%s%s", bootfile1, image_url, bootfile3);
+	return ret;
+}
+
+static int tcp_stream_on_create(struct tcp_stream *tcp)
+{
+	if ((tcp->rhost.s_addr != web_server_ip.s_addr) ||
+	    (tcp->rport != server_port))
+		return 0;
+
+	tcp->max_retry_count = WGET_RETRY_COUNT;
+	tcp->initial_timeout = WGET_TIMEOUT;
+	tcp->on_closed = tcp_stream_on_closed;
+	tcp->on_rcv_nxt_update = tcp_stream_on_rcv_nxt_update;
+	tcp->rx = tcp_stream_rx;
+	tcp->tx = tcp_stream_tx;
+	return 1;
 }
#define BLOCKSIZE 512
void wget_start(void)
 {
-	struct in_addr web_server_ip;
-	unsigned int server_port;
+	struct tcp_stream *tcp;
image_url = strchr(net_boot_file_name, ':');
    if (image_url > 0) {
@@ -486,12 +283,6 @@ void wget_start(void)
    	}
    }
-	net_set_timeout_handler(wget_timeout, wget_timeout_handler);
-	tcp_set_tcp_handler(wget_handler);
-
-	wget_timeout_count = 0;
-	current_wget_state = WGET_CLOSED;
-
    /*
     * Zero out server ether to force arp resolution in case
     * the server ip for the previous u-boot command, for example dns
@@ -500,14 +291,21 @@ void wget_start(void)
memset(net_server_ethaddr, 0, 6);
+	packets = 0;
+	net_boot_file_size = 0;
+	http_hdr_size = 0;
+	wget_tsize_num_hash = 0;
+	wget_loop_state = NETLOOP_FAIL;
+
    server_port = env_get_ulong("httpdstp", 10, SERVER_PORT) & 0xffff;
+	tcp_stream_set_on_create_handler(tcp_stream_on_create);
    tcp = tcp_stream_connect(web_server_ip, server_port);
    if (tcp == NULL) {
+		printf("No free tcp streams\n");
    	net_set_state(NETLOOP_FAIL);
    	return;
    }
-
-	wget_send(TCP_SYN, 0, 0, 0);
+	tcp_stream_put(tcp);
 }
#if (IS_ENABLED(CONFIG_CMD_DNS))
-- 
2.45.2


    