[U-Boot] [PATCH v7 1/4] Integrating TCP and wget into u-boot

[U-Boot] [PATCH v7 1/4] Integrating TCP and wget into u-boot

[DH at synoia.com]

From: Duncan Hare <DuncanCHare@yahoo.com>

All the code is new, and not copied from any source.

>>>>>
<<<<

Commit-notes
Why netboot:
Central management, including logs and change control,
coupled with with enhanced security and unauthorized
change detection and remediation by exposing a
small attack surface.

Why TCP:

Currently file transfer are done using tftp or NFS both
over udp. This requires a request to be sent from client
(u-boot) to the boot server.

For a 4 Mbyte kernel, with a 1k block size this requires
4,000 request for a block.

Using a large block size, one greater than the Ethernet
maximum frame size limitation, would require fragmentation,
which u-boot supports. However missing fragment recovery
requires timeout detection and re-transmission requests
for missing fragments.

UDP is ideally suited to fast single packet exchanges,
inquiry/response, for example dns, becuse of the lack of
connection overhead.

UDP as a file transport mechanism is slow, even in low
latency networks, because file transfer with udp requires
poll/response mechanism to provide transfer integrity.

In networks with large latency, for example: the internet,
UDP is even slower. What is a 30 second transfer on a local
boot server and LAN increase to over 3 minutes, because of
all the requests/response traffic.

This was anticipated in the evolution of the IP protocols
and TCP was developed and then enhanced for high latency high
bandwidth networks.

The current standard is TCP with selective acknowledgment.

In our testing we have reduce kernel transmission time to
around 0.4 seconds for a 4Mbyte kernel, with a 100 Mbps
downlink.

Why http and wget:

HTTP is the most efficient file retrieval protocol in common
use. The client send a single request, after TCP connection,
to receive a file of any length.

WGET is the application which implements http file transfer
outside browsers as a file transfer protocol. Versions of
wget exists on many operating systems.

END

Signed-off-by: Duncan Hare <DuncanCHare@yahoo.com>
---

Changes in v7:
Integrating TCP and wget into u-boot

 include/net.h | 25 +++++++++++++++++++------
 net/net.c     | 52 ++++++++++++++++++++++++++++++++++------------------
 net/ping.c    |  9 ++-------
 3 files changed, 55 insertions(+), 31 deletions(-)

diff --git a/include/net.h b/include/net.h
index 455b48f6c7..7e5f5a6a5b 100644
--- a/include/net.h
+++ b/include/net.h
@@ -15,17 +15,26 @@
 #include <asm/cache.h>
 #include <asm/byteorder.h>	/* for nton* / ntoh* stuff */
 
-#define DEBUG_LL_STATE 0	/* Link local state machine changes */
-#define DEBUG_DEV_PKT 0		/* Packets or info directed to the device */
-#define DEBUG_NET_PKT 0		/* Packets on info on the network at large */
+#define DEBUG_LL_STATE  0	/* Link local state machine changes */
+#define DEBUG_DEV_PKT   0	/* Packets or info directed to the device */
+#define DEBUG_NET_PKT   0	/* Packets on info on the network at large */
 #define DEBUG_INT_STATE 0	/* Internal network state changes */
 
 /*
  *	The number of receive packet buffers, and the required packet buffer
  *	alignment in memory.
  *
+ *	The number of buffers for TCP is used to calculate a static TCP window
+ *	size, becuse TCP window size is a promise to the sending TCP to be able
+ *	to buffer up to the window size of data.
+ *	When the sending TCP has a window size of outstanding unacknowledged
+ *	data, the sending TCP will stop sending.
  */
 
+#if defined(CONFIG_TCP)
+#define CONFIG_SYS_RX_ETH_BUFFER 12	/* For TCP */
+#endif
+
 #ifdef CONFIG_SYS_RX_ETH_BUFFER
 # define PKTBUFSRX	CONFIG_SYS_RX_ETH_BUFFER
 #else
@@ -354,6 +363,7 @@ struct vlan_ethernet_hdr {
 
 #define IPPROTO_ICMP	 1	/* Internet Control Message Protocol	*/
 #define IPPROTO_UDP	17	/* User Datagram Protocol		*/
+#define IPPROTO_TCP	 6	/* Transmission Control Protocol        */
 
 /*
  *	Internet Protocol (IP) header.
@@ -596,10 +606,10 @@ int net_set_ether(uchar *xet, const uchar *dest_ethaddr, uint prot);
 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot);
 
 /* Set IP header */
-void net_set_ip_header(uchar *pkt, struct in_addr dest, struct in_addr source);
+void net_set_ip_header(uchar *pkt, struct in_addr dest, struct in_addr source,
+		       u16  pkt_len, u8 prot);
 void net_set_udp_header(uchar *pkt, struct in_addr dest, int dport,
-				int sport, int len);
-
+			int sport, int len);
 /**
  * compute_ip_checksum() - Compute IP checksum
  *
@@ -670,6 +680,9 @@ static inline void net_send_packet(uchar *pkt, int len)
  * @param sport Source UDP port
  * @param payload_len Length of data after the UDP header
  */
+int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
+		       int payload_len, int proto);
+
 int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport,
 			int sport, int payload_len);
 
diff --git a/net/net.c b/net/net.c
index 4259c9e321..df4e7317e7 100644
--- a/net/net.c
+++ b/net/net.c
@@ -181,6 +181,7 @@ int		net_ntp_time_offset;
 static uchar net_pkt_buf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
 /* Receive packets */
 uchar *net_rx_packets[PKTBUFSRX];
+
 /* Current UDP RX packet handler */
 static rxhand_f *udp_packet_handler;
 /* Current ARP RX packet handler */
@@ -777,11 +778,23 @@ void net_set_timeout_handler(ulong iv, thand_f *f)
 }
 
 int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport, int sport,
-		int payload_len)
+			int payload_len)
+{
+	return net_send_ip_packet(ether, dest, dport, sport, payload_len,
+				  IPPROTO_UDP);
+}
+
+int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
+		       int payload_len, int proto)
 {
 	uchar *pkt;
 	int eth_hdr_size;
 	int pkt_hdr_size;
+	if (proto == IPPROTO_UDP) {
+		debug_cond(DEBUG_DEV_PKT,
+			   "UDP Send  (to=%pI4, from=%pI4, len=%d)\n",
+			   &dest, &net_ip, payload_len);
+	}
 
 	/* make sure the net_tx_packet is initialized (net_init() was called) */
 	assert(net_tx_packet != NULL);
@@ -799,9 +812,15 @@ int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport, int sport,
 	pkt = (uchar *)net_tx_packet;
 
 	eth_hdr_size = net_set_ether(pkt, ether, PROT_IP);
-	pkt += eth_hdr_size;
-	net_set_udp_header(pkt, dest, dport, sport, payload_len);
-	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
+	switch (proto) {
+	case IPPROTO_UDP:
+		net_set_udp_header(pkt + eth_hdr_size, dest,
+				   dport, sport, payload_len);
+		pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
+	break;
+	default:
+		return -1;
+	}
 
 	/* if MAC address was not discovered yet, do an ARP request */
 	if (memcmp(ether, net_null_ethaddr, 6) == 0) {
@@ -1157,9 +1176,6 @@ void net_process_received_packet(uchar *in_packet, int len)
 		/* Can't deal with anything except IPv4 */
 		if ((ip->ip_hl_v & 0xf0) != 0x40)
 			return;
-		/* Can't deal with IP options (headers != 20 bytes) */
-		if ((ip->ip_hl_v & 0x0f) > 0x05)
-			return;
 		/* Check the Checksum of the header */
 		if (!ip_checksum_ok((uchar *)ip, IP_HDR_SIZE)) {
 			debug("checksum bad\n");
@@ -1205,6 +1221,7 @@ void net_process_received_packet(uchar *in_packet, int len)
 		 * we send a tftp packet to a dead connection, or when
 		 * there is no server at the other end.
 		 */
+
 		if (ip->ip_p == IPPROTO_ICMP) {
 			receive_icmp(ip, len, src_ip, et);
 			return;
@@ -1365,8 +1382,7 @@ common:
 }
 /**********************************************************************/
 
-int
-net_eth_hdr_size(void)
+int net_eth_hdr_size(void)
 {
 	ushort myvlanid;
 
@@ -1426,25 +1442,28 @@ int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
 	}
 }
 
-void net_set_ip_header(uchar *pkt, struct in_addr dest, struct in_addr source)
+void net_set_ip_header(uchar *pkt, struct in_addr dest, struct in_addr source,
+		       u16  pkt_len, u8 prot)
 {
 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
 
 	/*
-	 *	Construct an IP header.
+	 *      Construct an IP header.
 	 */
 	/* IP_HDR_SIZE / 4 (not including UDP) */
 	ip->ip_hl_v  = 0x45;
 	ip->ip_tos   = 0;
-	ip->ip_len   = htons(IP_HDR_SIZE);
+	ip->ip_len   = htons(pkt_len);
 	ip->ip_id    = htons(net_ip_id++);
-	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
+	ip->ip_off   = htons(IP_FLAGS_DFRAG);   /* Don't fragment */
 	ip->ip_ttl   = 255;
+	ip->ip_p     = prot;
 	ip->ip_sum   = 0;
 	/* already in network byte order */
 	net_copy_ip((void *)&ip->ip_src, &source);
 	/* already in network byte order */
 	net_copy_ip((void *)&ip->ip_dst, &dest);
+	ip->ip_sum  = compute_ip_checksum(ip, IP_HDR_SIZE);
 }
 
 void net_set_udp_header(uchar *pkt, struct in_addr dest, int dport, int sport,
@@ -1460,11 +1479,8 @@ void net_set_udp_header(uchar *pkt, struct in_addr dest, int dport, int sport,
 	if (len & 1)
 		pkt[IP_UDP_HDR_SIZE + len] = 0;
 
-	net_set_ip_header(pkt, dest, net_ip);
-	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
-	ip->ip_p     = IPPROTO_UDP;
-	ip->ip_sum   = compute_ip_checksum(ip, IP_HDR_SIZE);
-
+	net_set_ip_header(pkt, dest, net_ip, IP_UDP_HDR_SIZE + len,
+			  IPPROTO_UDP);
 	ip->udp_src  = htons(sport);
 	ip->udp_dst  = htons(dport);
 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
diff --git a/net/ping.c b/net/ping.c
index 9508cf1160..254b646193 100644
--- a/net/ping.c
+++ b/net/ping.c
@@ -20,16 +20,11 @@ struct in_addr net_ping_ip;
 static void set_icmp_header(uchar *pkt, struct in_addr dest)
 {
 	/*
-	 *	Construct an IP and ICMP header.
+	 *	Construct an ICMP header.
 	 */
-	struct ip_hdr *ip = (struct ip_hdr *)pkt;
 	struct icmp_hdr *icmp = (struct icmp_hdr *)(pkt + IP_HDR_SIZE);
 
-	net_set_ip_header(pkt, dest, net_ip);
-
-	ip->ip_len   = htons(IP_ICMP_HDR_SIZE);
-	ip->ip_p     = IPPROTO_ICMP;
-	ip->ip_sum   = compute_ip_checksum(ip, IP_HDR_SIZE);
+	net_set_ip_header(pkt, dest, net_ip, IP_ICMP_HDR_SIZE, IPPROTO_ICMP);
 
 	icmp->type = ICMP_ECHO_REQUEST;
 	icmp->code = 0;
-- 
2.11.0

[U-Boot] [PATCH v7 2/4] Integrating TCP and wget into u-boot v7

[DH at synoia.com]

From: Duncan Hare <DuncanCHare@yahoo.com>

All the code is new, and not copied from any source.

>>>>>
<<<<

Commit-notes

Routine tcp_print_buffer() is used to print portions of
non zero terminated buffers. If there is an existing routine
please let me know. I'm from the world of length fields
not zero terminated strings (zOS).

TCP Prtocol stack,

Why TCP:

Currently u-boot file transfers are done using tftp or NFS,
both over udp. This requires a request to be sent from client
(u-boot) to the boot server for every block of data.

For a 4 Mbyte kernel, with a 1k block size this requires
4,000 request for a block.

Using a large block size, one greater than the Ethernet
maximum frame size limitation, would require fragmentation,
which u-boot supports. However, missing fragment recovery
requires timeout detection and re-transmission requests
for missing fragments.

UDP is ideally suited to fast single packet exchanges,
inquiry/response, for example dns, becuse of the lack of
connection overhead.

UDP as a file transport mechanism is slow, even in low
latency networks, because file transfer with udp requires
poll/response mechanism to provide transfer integrity.

In networks with large latency, for example: the internet,
UDP is even slower. What is a 30 second transfer on a local
boot server and LAN increase to over 3 minutes, because of
all the requests/response traffic.

This was anticipated in the evolution of the IP protocols
and TCP was developed and then enhanced for high latency high
bandwidth networks.

The current standard is TCP with selective acknowledgment.

In our testing we have reduce kernel transmission time to
around 0.4 seconds for a 4Mbyte kernel, with a 100 Mbps
downlink.

END

Signed-off-by: Duncan Hare <DuncanCHare@yahoo.com>
---

Changes in v7:
Integrating TCP and wget into u-boot

 include/net.h     |   8 +-
 include/net/tcp.h | 218 ++++++++++++++++
 net/Kconfig       |  35 +--
 net/Makefile      |   2 +-
 net/net.c         |  51 +++-
 net/tcp.c         | 749 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 1024 insertions(+), 39 deletions(-)
 create mode 100644 include/net/tcp.h
 create mode 100644 net/tcp.c

diff --git a/include/net.h b/include/net.h
index 7e5f5a6a5b..e29d804a23 100644
--- a/include/net.h
+++ b/include/net.h
@@ -548,7 +548,7 @@ extern int		net_restart_wrap;	/* Tried all network devices */
 
 enum proto_t {
 	BOOTP, RARP, ARP, TFTPGET, DHCP, PING, DNS, NFS, CDP, NETCONS, SNTP,
-	TFTPSRV, TFTPPUT, LINKLOCAL
+	TFTPSRV, TFTPPUT, LINKLOCAL, WGET
 };
 
 extern char	net_boot_file_name[1024];/* Boot File name */
@@ -681,11 +681,15 @@ static inline void net_send_packet(uchar *pkt, int len)
  * @param payload_len Length of data after the UDP header
  */
 int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
-		       int payload_len, int proto);
+		       int payload_len, int proto, u8 action, u32 tcp_seq_num,
+		       u32 tcp_ack_num);
 
 int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport,
 			int sport, int payload_len);
 
+int net_send_tcp_packet(int payload_len, int dport, int sport, u8 action,
+			u32 tcp_seq_num, u32 tcp_ack_num);
+
 /* Processes a received packet */
 void net_process_received_packet(uchar *in_packet, int len);
 
diff --git a/include/net/tcp.h b/include/net/tcp.h
new file mode 100644
index 0000000000..81f263351e
--- /dev/null
+++ b/include/net/tcp.h
@@ -0,0 +1,218 @@
+/*
+ *	TCP Support for file transfer.
+ *
+ *	Copyright 2017 Duncan Hare, All rights reserved.
+ *
+ *      SPDX-License-Identifier:        GPL-2.0
+ */
+
+#define TCP_ACTIVITY 127		/* Activity on downloading      */
+
+struct ip_tcp_hdr {
+	u8		ip_hl_v;	/* header length and version	*/
+	u8		ip_tos;		/* type of service		*/
+	u16		ip_len;		/* total length			*/
+	u16		ip_id;		/* identification		*/
+	u16		ip_off;		/* fragment offset field	*/
+	u8		ip_ttl;		/* time to live			*/
+	u8		ip_p;		/* protocol			*/
+	u16		ip_sum;		/* checksum			*/
+	struct in_addr	ip_src;		/* Source IP address		*/
+	struct in_addr	ip_dst;		/* Destination IP address	*/
+	u16		tcp_src;	/* TCP source port		*/
+	u16		tcp_dst;	/* TCP destination port		*/
+	u32		tcp_seq;	/* TCP sequence number		*/
+	u32		tcp_ack;	/* TCP Acknowledgment number	*/
+	u8		tcp_hlen;	/* 4 bits TCP header Length/4	*/
+					/* 4 bits Reserved		*/
+					/* 2 more bits reserved		*/
+	u8		tcp_flags;	/* see defines			*/
+	u16		tcp_win;	/* TCP windows size		*/
+	u16		tcp_xsum;	/* Checksum			*/
+	u16		tcp_ugr;	/* Pointer to urgent data	*/
+} __packed;
+
+#define IP_TCP_HDR_SIZE		(sizeof(struct ip_tcp_hdr))
+#define TCP_HDR_SIZE		(IP_TCP_HDR_SIZE  - IP_HDR_SIZE)
+
+#define TCP_DATA	0x00	/* Data Packet - internal use only	*/
+#define TCP_FIN		0x01	/* Finish flag				*/
+#define TCP_SYN		0x02	/* Synch (start) flag			*/
+#define TCP_RST		0x04	/* reset flag				*/
+#define TCP_PUSH	0x08	/* Push - Notify app			*/
+#define TCP_ACK		0x10	/* Acknowledgment of data received	*/
+#define TCP_URG		0x20	/* Urgent				*/
+#define TCP_ECE		0x40	/* Congestion control			*/
+#define TCP_CWR		0x80	/* Congestion Control			*/
+
+/*
+ * TCP header options, Seq, MSS, and SACK
+ */
+
+#define TCP_SACK 32			/* Number of packets analyzed   */
+					/* on leading edge of stream    */
+
+#define TCP_O_END	0x00		/* End of option list		*/
+#define TCP_1_NOP	0x01		/* Single padding NOP		*/
+#define TCP_O_NOP	0x01010101	/* NOPs pad to 32 bit boundary	*/
+#define TCP_O_MSS	0x02		/* MSS Size option		*/
+#define TCP_O_SCL	0x03		/* Window Scale option		*/
+#define TCP_P_SACK	0x04		/* SACK permitted		*/
+#define TCP_V_SACK	0x05		/* SACK values			*/
+#define TCP_O_TS	0x08		/* Timestanp option		*/
+#define TCP_OPT_LEN_2	0x02
+#define TCP_OPT_LEN_3	0x03
+#define TCP_OPT_LEN_4	0x04
+#define TCP_OPT_LEN_6	0x06
+#define TCP_OPT_LEN_8	0x08
+#define TCP_OPT_LEN_A	0x0a		/* Timestamp Length		*/
+
+/*
+ * Please review the warning in net.c about these two parameters.
+ * They are part of a promise of RX buffer size to the sending TCP
+ */
+
+#define TCP_MSS		1460		/* Max segment size - 1460	*/
+#define TCP_SCALE	0x01		/* Scale 1			*/
+
+struct tcp_mss {			/* TCP Mex Segment size		*/
+	u8	kind;			/* 0x02				*/
+	u8	len;			/* 0x04				*/
+	u16	mss;			/* 1460 - Max segment size	*/
+} __packed;
+
+struct tcp_scale {			/* TCP Windows Scale		*/
+	u8	kind;			/* 0x03				*/
+	u8	len;			/* 0x03				*/
+	u8	scale;			/* win shift fat fast networks	*/
+} __packed;
+
+struct tcp_sack_p {			/* SACK permitted		*/
+	u8	kind;			/* 0x04				*/
+	u8	len;			/* Length			*/
+} __packed;
+
+struct sack_edges {
+	u32	l;
+	u32	r;
+} __packed;
+
+#define TCP_SACK_SIZE (sizeof(struct sack_edges))
+
+#define TCP_SACK_HILLS	4
+
+struct tcp_sack_v {
+	u8	kind;			/* 0x05			        */
+	u8	len;				 /* Length		*/
+	struct	sack_edges hill[TCP_SACK_HILLS]; /* L & R widow edges	*/
+} __packed;
+
+struct tcp_t_opt {			/* TCP time stamps option	*/
+	u8	kind;			/* 0x08				*/
+	u8	len;			/* 0x0a				*/
+	u32	t_snd;			/* Sender timestamp		*/
+	u32	t_rcv;			/* Receiver timestamp		*/
+} __packed;
+
+#define TCP_TSOPT_SIZE	(sizeof(struct tcp_t_opt))
+
+/*
+ * ip tcp  structure with options
+ */
+
+struct ip_tcp_hdr_o {
+	struct	ip_tcp_hdr	hdr;
+	struct	tcp_mss		mss;
+	struct	tcp_scale	scale;
+	struct	tcp_sack_p	sack_p;
+	struct	tcp_t_opt	t_opt;
+	u8	end;
+} __packed;
+
+#define IP_TCP_O_SIZE		(sizeof(struct ip_tcp_hdr_o))
+
+struct ip_tcp_hdr_s {
+	struct	ip_tcp_hdr	hdr;
+	struct	tcp_t_opt	t_opt;
+	struct	tcp_sack_v	sack_v;
+	u8	end;
+} __packed;
+
+#define IP_TCP_SACK_SIZE	(sizeof(struct ip_tcp_hdr_s))
+
+/*
+ * TCP pseudo header definitions
+ */
+#define PSEUDO_PAD_SIZE	8
+
+struct pseudo_hdr {
+	u8 padding[PSEUDO_PAD_SIZE];	/* pseudo hdr size = ip_tcp hdr size */
+	struct in_addr p_src;
+	struct in_addr p_dst;
+	u8      rsvd;
+	u8      p;
+	u16     len;
+} __packed;
+
+#define PSEUDO_HDR_SIZE	(sizeof(struct pseudo_hdr)) - PSEUDO_PAD_SIZE
+
+/*
+ * union for building IP/TCP packet.
+ * build Pseudo header in packed buffer first, calculate TCP checksum
+ * then build IP header in packed  buffer.
+ */
+
+union tcp_build_pkt {
+	struct pseudo_hdr ph;
+	struct ip_tcp_hdr_o ip;
+	struct ip_tcp_hdr_s sack;
+	uchar  raw[1600];
+} __packed;
+
+/*
+ * TCP STATE MACHINE STATES FOR SOCKET
+ */
+
+enum TCP_STATE {
+	TCP_CLOSED,		/* Need to send SYN to connect		  */
+	TCP_SYN_SENT,		/* Trying to connect, waiting for SYN ACK */
+	TCP_ESTABLISHED,	/* both server & client have a connection */
+	TCP_CLOSE_WAIT,		/* Rec FIN, passed to app for FIN, ACK rsp*/
+	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 */
+};
+
+int tcp_find_in_buffer(uchar raw[], int payload_len, uchar field[],
+		       int field_len);
+void tcp_print_buffer(uchar raw[], int pkt_len, int payload_len,
+		      int hdr_len, bool hide);
+enum TCP_STATE tcp_get_tcp_state(void);
+void tcp_set_tcp_state(enum TCP_STATE new_state);
+int tcp_set_tcp_header(uchar *pkt, int dport, int sport, int payload_len,
+		       u8 action, u32 tcp_seq_num, u32 tcp_ack_num);
+
+/*
+ * An incoming packet handler.
+ * @param pkt    pointer to the application packet
+ * @param dport  destination UDP port
+ * @param sip    source IP address
+ * @param sport  source UDP port
+ * @param len    packet length
+ */
+typedef void rxhand_tcp(uchar *pkt, unsigned int dport,
+			struct in_addr sip, unsigned int sport,
+			unsigned int len);
+void tcp_set_tcp_handler(rxhand_tcp *f);
+
+void rxhand_tcp_f(union tcp_build_pkt *b, unsigned int len);
+
+/*
+ * An incoming TCP packet handler for the TCP protocol.
+ * There is also a dynamic function pointer for TCP based commands to
+ * receive incoming traffic after the TCP protocol code has done its work.
+ */
+
+void rxhand_action(u8 tcp_action, int payload_len, u32 tcp_seq_num,
+		   u32 tcp_ack_num, unsigned int pkt_len,
+		   union tcp_build_pkt *b);
diff --git a/net/Kconfig b/net/Kconfig
index 143c4416cd..895b93dea9 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -4,12 +4,12 @@
 
 menuconfig NET
 	bool "Networking support"
-	default y
 
 if NET
 
 config NET_RANDOM_ETHADDR
 	bool "Random ethaddr if unset"
+	select LIB_RAND
 	help
 	  Selecting this will allow the Ethernet interface to function
 	  even when the ethaddr variable for that interface is unset.
@@ -24,7 +24,6 @@ config NETCONSOLE
 
 config NET_TFTP_VARS
 	bool "Control TFTP timeout and count through environment"
-	depends on CMD_NET
 	default y
 	help
 	  If set, allows controlling the TFTP timeout through the
@@ -33,44 +32,22 @@ config NET_TFTP_VARS
 	  If unset, timeout and maximum are hard-defined as 1 second
 	  and 10 timouts per TFTP transfer.
 
-config BOOTP_BOOTPATH
-	bool "Enable BOOTP BOOTPATH"
-	depends on CMD_NET
-
-config BOOTP_DNS
-	bool "Enable bootp DNS"
-	depends on CMD_NET
-
-config BOOTP_GATEWAY
-	bool "Enable BOOTP gateway"
-	depends on CMD_NET
-
-config BOOTP_HOSTNAME
-	bool "Enable BOOTP hostname"
-	depends on CMD_NET
-
-config BOOTP_PXE
-	bool "Enable BOOTP PXE"
-	depends on CMD_NET
-
-config BOOTP_SUBNETMASK
-	bool "Enable BOOTP subnetmask"
-	depends on CMD_NET
-	depends on CMD_NET
-
 config BOOTP_PXE_CLIENTARCH
 	hex
-	depends on CMD_NET
         default 0x16 if ARM64
         default 0x15 if ARM
         default 0 if X86
 
 config BOOTP_VCI_STRING
 	string
-	depends on CMD_NET
 	default "U-Boot.armv7" if CPU_V7 || CPU_V7M
 	default "U-Boot.armv8" if ARM64
 	default "U-Boot.arm" if ARM
 	default "U-Boot"
 
+config TCP
+	bool "Include TCP for receiving files"
+	help
+	  TCP support for receiving files.
+
 endif   # if NET
diff --git a/net/Makefile b/net/Makefile
index ae54eee5af..25729ebeeb 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -25,7 +25,7 @@ obj-$(CONFIG_CMD_PING) += ping.o
 obj-$(CONFIG_CMD_RARP) += rarp.o
 obj-$(CONFIG_CMD_SNTP) += sntp.o
 obj-$(CONFIG_CMD_NET)  += tftp.o
-
+obj-$(CONFIG_TCP)      += tcp.o
 # Disable this warning as it is triggered by:
 # sprintf(buf, index ? "foo%d" : "foo", index)
 # and this is intentional usage.
diff --git a/net/net.c b/net/net.c
index df4e7317e7..7adc4b472c 100644
--- a/net/net.c
+++ b/net/net.c
@@ -107,6 +107,9 @@
 #if defined(CONFIG_CMD_SNTP)
 #include "sntp.h"
 #endif
+#if defined(CONFIG_TCP)
+#include <net/tcp.h>
+#endif
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -382,6 +385,9 @@ void net_init(void)
 
 		/* Only need to setup buffer pointers once. */
 		first_call = 0;
+#if defined(CONFIG_TCP)
+		tcp_set_tcp_state(TCP_CLOSED);
+#endif
 	}
 
 	net_init_loop();
@@ -781,11 +787,22 @@ int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport, int sport,
 			int payload_len)
 {
 	return net_send_ip_packet(ether, dest, dport, sport, payload_len,
-				  IPPROTO_UDP);
+				  IPPROTO_UDP, 0, 0, 0);
+}
+
+#if defined(CONFIG_TCP)
+int net_send_tcp_packet(int payload_len, int dport, int sport, u8 action,
+			u32 tcp_seq_num, u32 tcp_ack_num)
+{
+	return net_send_ip_packet(net_server_ethaddr, net_server_ip, dport,
+				  sport, payload_len, IPPROTO_TCP, action,
+				  tcp_seq_num, tcp_ack_num);
 }
+#endif
 
 int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
-		       int payload_len, int proto)
+		       int payload_len, int proto, u8 action, u32 tcp_seq_num,
+		       u32 tcp_ack_num)
 {
 	uchar *pkt;
 	int eth_hdr_size;
@@ -794,6 +811,13 @@ int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
 		debug_cond(DEBUG_DEV_PKT,
 			   "UDP Send  (to=%pI4, from=%pI4, len=%d)\n",
 			   &dest, &net_ip, payload_len);
+#if defined(CONFIG_TCP)
+
+	} else {
+		debug_cond(DEBUG_DEV_PKT,
+			   "TCP Send  (%pI4, %pI4, len=%d, A=%x)\n",
+			   &dest, &net_ip, payload_len, action);
+#endif
 	}
 
 	/* make sure the net_tx_packet is initialized (net_init() was called) */
@@ -812,15 +836,19 @@ int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
 	pkt = (uchar *)net_tx_packet;
 
 	eth_hdr_size = net_set_ether(pkt, ether, PROT_IP);
-	switch (proto) {
-	case IPPROTO_UDP:
+	if (proto == IPPROTO_UDP) {
 		net_set_udp_header(pkt + eth_hdr_size, dest,
 				   dport, sport, payload_len);
 		pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
-	break;
-	default:
-		return -1;
+
+#if defined(CONFIG_TCP)
+	} else {
+		pkt_hdr_size = eth_hdr_size +
+		tcp_set_tcp_header(pkt + eth_hdr_size, dport, sport,
+				   payload_len, action,
+				   tcp_seq_num, tcp_ack_num);
 	}
+#endif
 
 	/* if MAC address was not discovered yet, do an ARP request */
 	if (memcmp(ether, net_null_ethaddr, 6) == 0) {
@@ -1225,6 +1253,15 @@ void net_process_received_packet(uchar *in_packet, int len)
 		if (ip->ip_p == IPPROTO_ICMP) {
 			receive_icmp(ip, len, src_ip, et);
 			return;
+#if defined(CONFIG_TCP)
+		} else if (ip->ip_p == IPPROTO_TCP) {
+			debug_cond(DEBUG_DEV_PKT,
+				   "TCP PH (to=%pI4, from=%pI4, len=%d)\n",
+				   &dst_ip, &src_ip, len);
+
+				rxhand_tcp_f((union tcp_build_pkt *)ip, len);
+			return;
+#endif
 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
 			return;
 		}
diff --git a/net/tcp.c b/net/tcp.c
new file mode 100644
index 0000000000..612a6a4b7d
--- /dev/null
+++ b/net/tcp.c
@@ -0,0 +1,749 @@
+/*
+ *	Copyright 2017 Duncan Hare, all rights reserved.
+ *	SPDX-License-Identifier:        GPL-2.0
+ */
+
+/*
+ * General Desription:
+ *
+ * TCP support for the wget command, for fast file downloading.
+ *
+ * HTTP/TCP Receiver:
+ *
+ *      Prequeisites:   - own ethernet address
+ *                      - own IP address
+ *                      - Server IP address
+ *                      - Server with TCP
+ *                      - TCP application (eg wget)
+ *      Next Step       HTTPS?
+ */
+#include <common.h>
+#include <command.h>
+#include <console.h>
+#include <environment.h>
+#include <errno.h>
+#include <net.h>
+#include <net/tcp.h>
+#if defined(CONFIG_CMD_WGET)
+#include "net/wget.h"
+#endif
+
+/*
+ * TCP sliding window  control
+ * used by us to request re-TX
+ */
+
+static struct tcp_sack_v tcp_lost;
+
+/* TCP option timestamp */
+static u32 loc_timestamp;
+static u32 rmt_timestamp;
+
+u32 tcp_seq_init;
+u32 tcp_ack_edge;
+u32 tcp_seq_max;
+
+int tcp_activity_count;
+
+/*
+ * Search for TCP_SACK and review the
+ * comments before the code section
+ * TCP_SACK is the number of packets
+ * at the front of the stream
+ */
+
+enum pkt_state {PKT, NOPKT};
+struct sack_r {
+	struct sack_edges se;
+	enum   pkt_state st;
+};
+
+struct sack_r edge_a[TCP_SACK];
+unsigned int sack_idx;
+unsigned int prev_len;
+
+/* TCP connection state */
+static enum TCP_STATE tcp_state;
+
+/*
+ * An incoming TCP packet handler for the TCP protocol.
+ * There is also a dymanic function pointer for TCP based commads to
+ * receive incoming traffic after the TCP protocol code has done its work.
+ */
+
+/* Current TCP RX packet handler */
+static rxhand_tcp *tcp_packet_handler;
+
+enum TCP_STATE tcp_get_tcp_state(void)
+{
+	return tcp_state;
+}
+
+void tcp_set_tcp_state(enum TCP_STATE new_state)
+{
+	tcp_state = new_state;
+}
+
+void tcp_print_buffer(uchar raw[], int pkt_len, int payload_len,
+		      int hdr_len, bool hide)
+{
+	int i;
+
+	for (i = pkt_len - payload_len; i < pkt_len; i++) {
+		if (i <= hdr_len)
+			printf("%02X", raw[i]);
+		else if ((raw[i] > 0x19) && (raw[i] < 0x7f))
+			putc(raw[i]);
+		else if (hide == 0)
+			putc(raw[i]);
+		else
+			printf("%02X", raw[i]);
+	}
+	printf("%s", "\n");
+}
+
+int tcp_find_in_buffer(uchar raw[], int payload_len, uchar field[],
+		       int field_len)
+{
+	int i, j;
+
+	for (i = 0; i < payload_len; i++) {
+		if (raw[i] == field[0]) {
+			for (j = 1; j < field_len; j++) {
+				if (raw[i + j] != field[j])
+					break;
+			if (j == field_len)
+				return i;
+			}
+		}
+	}
+	return 0;
+}
+
+static void dummy_handler(uchar *pkt, unsigned int dport,
+			  struct in_addr sip, unsigned int sport,
+			  unsigned int len)
+{
+}
+
+void tcp_set_tcp_handler(rxhand_tcp *f)
+{
+	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;
+}
+
+u16 tcp_set_pseudo_header(uchar *pkt, struct in_addr src, struct in_addr dest,
+			  int tcp_len, int pkt_len)
+{
+	union tcp_build_pkt *b = (union tcp_build_pkt *)pkt;
+	int checksum_len;
+
+	/*
+	 * Pseudo header
+	 *
+	 * Zero the byte after the last byte so that the header checksum
+	 * will always work.
+	 */
+
+	pkt[pkt_len] = 0x00;
+
+	net_copy_ip((void *)&b->ph.p_src, &src);
+	net_copy_ip((void *)&b->ph.p_dst, &dest);
+	b->ph.rsvd	= 0x00;
+	b->ph.p		= IPPROTO_TCP;
+	b->ph.len	= htons(tcp_len);
+	checksum_len	= tcp_len + PSEUDO_HDR_SIZE;
+
+	debug_cond(DEBUG_DEV_PKT,
+		   "TCP Pesudo  Header  (to=%pI4, from=%pI4, Len=%d)\n",
+		   &b->ph.p_dst, &b->ph.p_src, checksum_len);
+
+	return compute_ip_checksum(pkt + PSEUDO_PAD_SIZE, checksum_len);
+}
+
+int net_set_ack_options(union tcp_build_pkt *b)
+{
+	b->sack.hdr.tcp_hlen  = (TCP_HDR_SIZE >> 2) << 4;
+
+	b->sack.t_opt.kind		= TCP_O_TS;
+	b->sack.t_opt.len		= TCP_OPT_LEN_A;
+	b->sack.t_opt.t_snd		= htons(loc_timestamp);
+	b->sack.t_opt.t_rcv		= rmt_timestamp;
+	b->sack.sack_v.kind             = 0x01;
+	b->sack.sack_v.len		= 0x00;
+
+	if (tcp_lost.len > TCP_OPT_LEN_2) {
+		debug_cond(DEBUG_DEV_PKT, "TCP ack opt lost.len %x\n",
+			   tcp_lost.len);
+		b->sack.sack_v.len              = tcp_lost.len;
+		b->sack.sack_v.kind		= TCP_V_SACK;
+		b->sack.sack_v.hill[0].l = htonl(tcp_lost.hill[0].l);
+		b->sack.sack_v.hill[0].r = htonl(tcp_lost.hill[0].r);
+
+		/*
+		 * These SACK structures are initialized with NOPs to
+		 * provide TCP header alignment padding. There are 4
+		 * SACK structures used for both header padding and
+		 * internally.
+		 */
+
+		b->sack.sack_v.hill[1].l = htonl(tcp_lost.hill[1].l);
+		b->sack.sack_v.hill[1].r = htonl(tcp_lost.hill[1].r);
+		b->sack.sack_v.hill[2].l = htonl(tcp_lost.hill[2].l);
+		b->sack.sack_v.hill[2].r = htonl(tcp_lost.hill[2].r);
+		b->sack.sack_v.hill[3].l = TCP_O_NOP;
+		b->sack.sack_v.hill[3].r = TCP_O_NOP;
+	}
+
+	/*
+	* TCP lengths are stored as a rounded up number of 32 bit words
+	* Add 3 to length round up, rounded, then divided into the length
+	* in 32 bit words.
+	*/
+
+	b->sack.hdr.tcp_hlen = (((TCP_HDR_SIZE + TCP_TSOPT_SIZE
+				+ tcp_lost.len + 3)  >> 2) << 4);
+
+	/*
+	 * This returns the actual rounded up length of the
+	 * TCP header to add to the total packet length
+	*/
+
+	return b->sack.hdr.tcp_hlen >> 2;
+}
+
+void net_set_syn_options(union tcp_build_pkt *b)
+{
+	tcp_lost.len		= 0;
+	b->ip.hdr.tcp_hlen      = 0xa0;
+
+	b->ip.mss.kind          = TCP_O_MSS;
+	b->ip.mss.len           = TCP_OPT_LEN_4;
+	b->ip.mss.mss           = htons(TCP_MSS);
+	b->ip.scale.kind        = TCP_O_SCL;
+	b->ip.scale.scale       = TCP_SCALE;
+	b->ip.scale.len         = TCP_OPT_LEN_3;
+	b->ip.sack_p.kind       = TCP_P_SACK;
+	b->ip.sack_p.len        = TCP_OPT_LEN_2;
+	b->ip.t_opt.kind        = TCP_O_TS;
+	b->ip.t_opt.len         = TCP_OPT_LEN_A;
+	loc_timestamp           = get_ticks() % 3072;
+	rmt_timestamp           = 0x00000000;
+	b->ip.t_opt.t_snd       = 0;
+	b->ip.t_opt.t_rcv       = 0x00000000;
+	b->ip.end               = TCP_O_END;
+}
+
+int tcp_set_tcp_header(uchar *pkt, int dport, int sport, int payload_len,
+		       u8 action, u32 tcp_seq_num, u32 tcp_ack_num)
+{
+	union tcp_build_pkt *b = (union tcp_build_pkt *)pkt;
+	int	pkt_hdr_len;
+	int	pkt_len;
+	int	tcp_len;
+
+	b->ip.hdr.tcp_flags	= action;
+	pkt_hdr_len		= IP_TCP_HDR_SIZE;
+	b->ip.hdr.tcp_hlen      = 0x50;		/* Header is 5 32 bit words  */
+						/* 4 bits TCP header Length/4*/
+						/* 4 bits Reserved           */
+						/* For options		     */
+	switch (action) {
+	case TCP_SYN:
+		debug_cond(DEBUG_DEV_PKT,
+			   "TCP Hdr:SYN (%pI4, %pI4, sq=%d, ak=%d)\n",
+			   &net_server_ip, &net_ip,
+			   tcp_seq_num, tcp_ack_num);
+		tcp_activity_count = 0;
+		net_set_syn_options(b);
+		tcp_seq_num = 0;
+		tcp_ack_num = 0;
+		pkt_hdr_len = IP_TCP_O_SIZE;
+		if (tcp_state == TCP_SYN_SENT) {  /* Too many sins */
+			action    = TCP_FIN;
+			tcp_state = TCP_FIN_WAIT_1;
+		} else {
+			tcp_state = TCP_SYN_SENT;
+		}
+	break;
+	case TCP_ACK:
+		pkt_hdr_len         = IP_HDR_SIZE +
+				      net_set_ack_options(b);
+		b->ip.hdr.tcp_flags = action;
+		debug_cond(DEBUG_DEV_PKT,
+			   "TCP Hdr:ACK (%pI4, %pI4, s=%d, a=%d, A=%x)\n",
+			   &net_server_ip, &net_ip, tcp_seq_num, tcp_ack_num,
+			   action);
+	break;
+	case TCP_FIN:
+		debug_cond(DEBUG_DEV_PKT,
+			   "TCP Hdr:FIN  (%pI4, %pI4, s=%d, a=%d)\n",
+			   &net_server_ip, &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;
+
+	/* 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;
+		tcp_ack_edge++;
+		debug_cond(DEBUG_DEV_PKT,
+			   "TCP Hdr:FIN ACK PSH(%pI4, %pI4, s=%d, a=%d, A=%x)\n",
+			   &net_server_ip, &net_ip,
+			   tcp_seq_num, tcp_ack_edge, action);
+					/* FALLTHRU */
+	default:
+		pkt_hdr_len         = IP_HDR_SIZE +
+				      net_set_ack_options(b);
+		b->ip.hdr.tcp_flags = action | TCP_PUSH | TCP_ACK;
+		debug_cond(DEBUG_DEV_PKT,
+			   "TCP Hdr:dft  (%pI4, %pI4, s=%d, a=%d, A=%x)\n",
+			   &net_server_ip, &net_ip,
+			   tcp_seq_num, tcp_ack_num, action);
+	}
+
+	pkt_len	= pkt_hdr_len + payload_len;
+	tcp_len	= pkt_len - IP_HDR_SIZE;
+
+	/* TCP Header */
+	b->ip.hdr.tcp_ack       = htonl(tcp_ack_edge);
+	b->ip.hdr.tcp_src	= htons(sport);
+	b->ip.hdr.tcp_dst	= htons(dport);
+	b->ip.hdr.tcp_seq	= htonl(tcp_seq_num);
+	tcp_seq_num		= tcp_seq_num + payload_len;
+
+	/*
+	 * TCP window size - TCP header variable tcp_win.
+	 * Change tcp_win only if you have an understanding of network
+	 * overrun, congestion, TCP segment sizes, TCP windows, TCP scale,
+	 * queuing theory  and packet buffering. If there are too few buffers,
+	 * there will be data loss, recovery may work or the sending TCP,
+	 * the server, could abort the stream transmission.
+	 * MSS is governed by maximum Ethernet frame length.
+	 * The number of buffers is governed by the desire to have a queue of
+	 * full buffers to be processed at the destination to maximize
+	 * throughput. Temporary memory use for the boot phase on modern
+	 * SOCs is may not be considered a constraint to buffer space, if
+	 * 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_xsum	= 0x0000;
+	b->ip.hdr.tcp_ugr	= 0x0000;
+
+	b->ip.hdr.tcp_xsum = tcp_set_pseudo_header(pkt, net_ip, net_server_ip,
+						   tcp_len, pkt_len);
+
+	/*
+	 * IP Header
+	 */
+
+	net_set_ip_header((uchar *)&b->ip, net_server_ip, net_ip,
+			  pkt_len, IPPROTO_TCP);
+
+	return pkt_hdr_len;
+}
+
+/*
+ * Selective Acknowledgment (Essential for fast stream transfer)
+ *
+ * Before modifying this section of code, which the author found difficult
+ * to write, please be familiar with the SACK (Selective Acknowledgment) RFCs.
+ */
+
+void tcp_hole(u32 tcp_seq_num, u32 len, u32 tcp_seq_max)
+{
+	unsigned int idx_sack;
+	unsigned int sack_end = TCP_SACK - 1;
+	unsigned int sack_in;
+	unsigned int hill = 0;
+	enum pkt_state expect = PKT;
+
+	u32 seq   = tcp_seq_num - tcp_seq_init;
+	u32 hol_l = tcp_ack_edge - tcp_seq_init;
+	u32 hol_r = 0;
+
+	/* Place seq number in correct place */
+
+	if (prev_len == 0)
+		prev_len = len;
+	idx_sack = sack_idx + ((tcp_seq_num - tcp_ack_edge) / prev_len);
+	if (idx_sack < TCP_SACK) {
+		edge_a[idx_sack].se.l = tcp_seq_num;
+		edge_a[idx_sack].se.r = tcp_seq_num + len;
+		edge_a[idx_sack].st   = PKT;
+
+		/* The fin (last) packet is not the same length as data packets,
+		 * and if it's length is recorded and used for array index
+		 * the array index calculations break.
+		 */
+		if (prev_len < len)
+			prev_len = len;
+	}
+
+	debug_cond(DEBUG_DEV_PKT,
+		   "TCP 1 seq %d, edg %d, len %d, sack_idx %d, sack_end %d\n",
+		    seq, hol_l, len, sack_idx, sack_end);
+
+	/* Right edge of contiguous stream, is the left edge of first hill */
+
+	hol_l = tcp_seq_num - tcp_seq_init;
+	hol_r = hol_l + len;
+
+	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");
+					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++;
+					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 (hill < TCP_SACK_HILLS)
+						tcp_lost.hill[hill].r =
+							edge_a[sack_in].se.r;
+				if (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 (tcp_lost.len <= TCP_OPT_LEN_2)
+		sack_idx = 0;
+}
+
+void tcp_parse_options(uchar *o, int o_len)
+{
+	struct tcp_t_opt  *tsopt;
+	uchar *p = o;
+
+	for (p = o; p < (o + o_len); p = p + p[1]) {
+		if (p[1] != 0) {
+			switch (p[0]) {
+			case TCP_O_END:
+				return;
+			case TCP_O_MSS:
+			break;
+			case TCP_O_SCL:
+			break;
+			case TCP_P_SACK:
+			break;
+			case TCP_V_SACK:
+			break;
+			case TCP_O_TS:
+				tsopt = (struct tcp_t_opt *)p;
+				rmt_timestamp = tsopt->t_snd;
+				return;
+			break;
+			}
+			if (p[0] == TCP_O_NOP)
+				p++;
+		} else {
+			return;
+		}
+	}
+}
+
+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;
+		tcp_state = TCP_CLOSED;
+		net_set_state(NETLOOP_FAIL);
+		debug_cond(DEBUG_INT_STATE, "TCP Reset %x\n", tcp_flags);
+		return TCP_RST;
+	}
+
+	switch  (tcp_state) {
+	case TCP_CLOSED:
+	debug_cond(DEBUG_INT_STATE, "TCP CLOSED %x\n", tcp_flags);
+		if (tcp_fin)
+			action = TCP_DATA;
+		if (tcp_syn)
+			action = TCP_RST;
+		if (tcp_ack)
+			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;
+			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;
+				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) && (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;
+		}
+		if (tcp_push)
+			action = action | TCP_PUSH;
+		if (tcp_syn)
+			action = TCP_ACK + TCP_RST;
+	break;
+	case TCP_CLOSE_WAIT:
+		debug_cond(DEBUG_INT_STATE, "TCP_CLOSE_WAIT (%x)\n", tcp_flags);
+		action = TCP_DATA;			/* Wait for app	*/
+	break;
+	case TCP_FIN_WAIT_2:
+		debug_cond(DEBUG_INT_STATE, "TCP_FIN_WAIT_2 (%x)\n", tcp_flags);
+		if (tcp_fin)
+			action =  TCP_DATA;
+		if (tcp_syn)
+			action =  TCP_DATA;
+		if (tcp_ack) {
+			action =  TCP_PUSH | TCP_ACK;
+			tcp_state = TCP_CLOSED;
+			puts("\n");
+		}
+	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;
+			 tcp_state = TCP_FIN_WAIT_2;
+		}
+		if (tcp_syn)
+			action =  TCP_RST;
+		if (tcp_ack) {
+			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_fin)
+			action = TCP_DATA;
+		if (tcp_syn)
+			action = TCP_RST;
+		if (tcp_ack) {
+			action = TCP_PUSH;
+			tcp_state = TCP_CLOSED;
+			puts("\n");
+		}
+	break;
+	}
+	return action;
+}
+
+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;
+	u32 tcp_ack_num;
+	struct in_addr action_and_state;
+
+	int tcp_hdr_len;
+	int 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);
+
+		debug_cond(DEBUG_DEV_PKT,
+			   "In__________________________________________\n");
+
+	b->ip.hdr.ip_src	= net_server_ip;
+	b->ip.hdr.ip_dst	= net_ip;
+	b->ip.hdr.ip_sum	= 0x0000;
+	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 = 0x0000;
+	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 = (b->ip.hdr.tcp_hlen >> 2);
+	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);
+
+	/*
+	 * Sent first packet send from server as first to app
+	 * Other packets could be ordered, but are currently not ordered.
+	 */
+
+	tcp_action  = tcp_state_machine(b->ip.hdr.tcp_flags,
+					&tcp_seq_num, payload_len);
+
+	/*
+	 * State altering command to be sent.
+	 * The packet sequence and ack numbers are in the tcp_seq_num
+	 * and tcp_ack_num variables. The current packet, its position
+	 * in the data stream, is the in the range of those variables.
+	 *
+	 * In the "application push" invocation, the TCP header with all
+	 * its information is pointed to by the packet pointer.
+	 *
+	 * in the typedef
+	 * 	void rxhand_tcp(uchar *pkt, unsigned int dport,
+	 *                      struct in_addr sip, unsigned int sport,
+	 *                      unsigned int len);
+	 * *pkt is the pointer to the payload
+	 * dport is used for tcp_seg_num
+	 * action_and_state.s_addr is used for TCP state
+	 * sport is used for tcp_ack_num (which is unused by the app)
+	 * pkt_ length is the payload length.
+	 *
+	 * TCP_PUSH from the state machine with a payload length of 0 is a
+	 * connect or disconnect event
+	 */
+
+	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 Seq & Ack  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);
+	}
+}
-- 
2.11.0

[U-Boot] [PATCH v7 2/4] Integrating TCP and wget into u-boot v7

[Joe Hershberger]

Hi Duncan,

The subject of all these patches ("Integrating TCP and wget into
u-boot") is what should be the title of a cover letter. You need to
give each patch a reasonable subject about that patch, not all of them
together.

On Thu, Mar 1, 2018 at 8:59 PM,  <DH@synoia.com> wrote:
> From: Duncan Hare <DuncanCHare@yahoo.com>
>
> All the code is new, and not copied from any source.

This is what should be inside the "Commit-notes:" section... All the
things you currently have there should be outside.

>
>>>>>>
> <<<<
>
> Commit-notes

You are missing a ':' so the tool is not detecting this.

>
> Routine tcp_print_buffer() is used to print portions of
> non zero terminated buffers. If there is an existing routine
> please let me know. I'm from the world of length fields
> not zero terminated strings (zOS).
>
> TCP Prtocol stack,
>
> Why TCP:
>
> Currently u-boot file transfers are done using tftp or NFS,
> both over udp. This requires a request to be sent from client
> (u-boot) to the boot server for every block of data.
>
> For a 4 Mbyte kernel, with a 1k block size this requires
> 4,000 request for a block.
>
> Using a large block size, one greater than the Ethernet
> maximum frame size limitation, would require fragmentation,
> which u-boot supports. However, missing fragment recovery
> requires timeout detection and re-transmission requests
> for missing fragments.
>
> UDP is ideally suited to fast single packet exchanges,
> inquiry/response, for example dns, becuse of the lack of
> connection overhead.
>
> UDP as a file transport mechanism is slow, even in low
> latency networks, because file transfer with udp requires
> poll/response mechanism to provide transfer integrity.
>
> In networks with large latency, for example: the internet,
> UDP is even slower. What is a 30 second transfer on a local
> boot server and LAN increase to over 3 minutes, because of
> all the requests/response traffic.
>
> This was anticipated in the evolution of the IP protocols
> and TCP was developed and then enhanced for high latency high
> bandwidth networks.
>
> The current standard is TCP with selective acknowledgment.
>
> In our testing we have reduce kernel transmission time to
> around 0.4 seconds for a 4Mbyte kernel, with a 100 Mbps
> downlink.
>
> END
>
> Signed-off-by: Duncan Hare <DuncanCHare@yahoo.com>
> ---
>
> Changes in v7:
> Integrating TCP and wget into u-boot

A much more appropriate thing to have put here would be something like
"Fixed naming of x variable" and "Changed file location of z.h". The
point of this is what you changed in this version of the patch.

>
>  include/net.h     |   8 +-
>  include/net/tcp.h | 218 ++++++++++++++++
>  net/Kconfig       |  35 +--
>  net/Makefile      |   2 +-
>  net/net.c         |  51 +++-
>  net/tcp.c         | 749 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  6 files changed, 1024 insertions(+), 39 deletions(-)
>  create mode 100644 include/net/tcp.h
>  create mode 100644 net/tcp.c
>
> diff --git a/include/net.h b/include/net.h
> index 7e5f5a6a5b..e29d804a23 100644
> --- a/include/net.h
> +++ b/include/net.h
> @@ -548,7 +548,7 @@ extern int          net_restart_wrap;       /* Tried all network devices */
>
>  enum proto_t {
>         BOOTP, RARP, ARP, TFTPGET, DHCP, PING, DNS, NFS, CDP, NETCONS, SNTP,
> -       TFTPSRV, TFTPPUT, LINKLOCAL
> +       TFTPSRV, TFTPPUT, LINKLOCAL, WGET
>  };
>
>  extern char    net_boot_file_name[1024];/* Boot File name */
> @@ -681,11 +681,15 @@ static inline void net_send_packet(uchar *pkt, int len)
>   * @param payload_len Length of data after the UDP header
>   */
>  int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
> -                      int payload_len, int proto);
> +                      int payload_len, int proto, u8 action, u32 tcp_seq_num,
> +                      u32 tcp_ack_num);
>
>  int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport,
>                         int sport, int payload_len);
>
> +int net_send_tcp_packet(int payload_len, int dport, int sport, u8 action,
> +                       u32 tcp_seq_num, u32 tcp_ack_num);
> +
>  /* Processes a received packet */
>  void net_process_received_packet(uchar *in_packet, int len);
>
> diff --git a/include/net/tcp.h b/include/net/tcp.h
> new file mode 100644
> index 0000000000..81f263351e
> --- /dev/null
> +++ b/include/net/tcp.h
> @@ -0,0 +1,218 @@
> +/*
> + *     TCP Support for file transfer.
> + *
> + *     Copyright 2017 Duncan Hare, All rights reserved.
> + *
> + *      SPDX-License-Identifier:        GPL-2.0
> + */
> +
> +#define TCP_ACTIVITY 127               /* Activity on downloading      */
> +
> +struct ip_tcp_hdr {
> +       u8              ip_hl_v;        /* header length and version    */
> +       u8              ip_tos;         /* type of service              */
> +       u16             ip_len;         /* total length                 */
> +       u16             ip_id;          /* identification               */
> +       u16             ip_off;         /* fragment offset field        */
> +       u8              ip_ttl;         /* time to live                 */
> +       u8              ip_p;           /* protocol                     */
> +       u16             ip_sum;         /* checksum                     */
> +       struct in_addr  ip_src;         /* Source IP address            */
> +       struct in_addr  ip_dst;         /* Destination IP address       */
> +       u16             tcp_src;        /* TCP source port              */
> +       u16             tcp_dst;        /* TCP destination port         */
> +       u32             tcp_seq;        /* TCP sequence number          */
> +       u32             tcp_ack;        /* TCP Acknowledgment number    */
> +       u8              tcp_hlen;       /* 4 bits TCP header Length/4   */
> +                                       /* 4 bits Reserved              */
> +                                       /* 2 more bits reserved         */
> +       u8              tcp_flags;      /* see defines                  */
> +       u16             tcp_win;        /* TCP windows size             */
> +       u16             tcp_xsum;       /* Checksum                     */
> +       u16             tcp_ugr;        /* Pointer to urgent data       */
> +} __packed;
> +
> +#define IP_TCP_HDR_SIZE                (sizeof(struct ip_tcp_hdr))
> +#define TCP_HDR_SIZE           (IP_TCP_HDR_SIZE  - IP_HDR_SIZE)
> +
> +#define TCP_DATA       0x00    /* Data Packet - internal use only      */
> +#define TCP_FIN                0x01    /* Finish flag                          */
> +#define TCP_SYN                0x02    /* Synch (start) flag                   */
> +#define TCP_RST                0x04    /* reset flag                           */
> +#define TCP_PUSH       0x08    /* Push - Notify app                    */
> +#define TCP_ACK                0x10    /* Acknowledgment of data received      */
> +#define TCP_URG                0x20    /* Urgent                               */
> +#define TCP_ECE                0x40    /* Congestion control                   */
> +#define TCP_CWR                0x80    /* Congestion Control                   */
> +
> +/*
> + * TCP header options, Seq, MSS, and SACK
> + */
> +
> +#define TCP_SACK 32                    /* Number of packets analyzed   */
> +                                       /* on leading edge of stream    */
> +
> +#define TCP_O_END      0x00            /* End of option list           */
> +#define TCP_1_NOP      0x01            /* Single padding NOP           */
> +#define TCP_O_NOP      0x01010101      /* NOPs pad to 32 bit boundary  */
> +#define TCP_O_MSS      0x02            /* MSS Size option              */
> +#define TCP_O_SCL      0x03            /* Window Scale option          */
> +#define TCP_P_SACK     0x04            /* SACK permitted               */
> +#define TCP_V_SACK     0x05            /* SACK values                  */
> +#define TCP_O_TS       0x08            /* Timestanp option             */
> +#define TCP_OPT_LEN_2  0x02
> +#define TCP_OPT_LEN_3  0x03
> +#define TCP_OPT_LEN_4  0x04
> +#define TCP_OPT_LEN_6  0x06
> +#define TCP_OPT_LEN_8  0x08
> +#define TCP_OPT_LEN_A  0x0a            /* Timestamp Length             */
> +
> +/*
> + * Please review the warning in net.c about these two parameters.
> + * They are part of a promise of RX buffer size to the sending TCP
> + */
> +
> +#define TCP_MSS                1460            /* Max segment size - 1460      */
> +#define TCP_SCALE      0x01            /* Scale 1                      */
> +
> +struct tcp_mss {                       /* TCP Mex Segment size         */
> +       u8      kind;                   /* 0x02                         */
> +       u8      len;                    /* 0x04                         */
> +       u16     mss;                    /* 1460 - Max segment size      */
> +} __packed;
> +
> +struct tcp_scale {                     /* TCP Windows Scale            */
> +       u8      kind;                   /* 0x03                         */
> +       u8      len;                    /* 0x03                         */
> +       u8      scale;                  /* win shift fat fast networks  */
> +} __packed;
> +
> +struct tcp_sack_p {                    /* SACK permitted               */
> +       u8      kind;                   /* 0x04                         */
> +       u8      len;                    /* Length                       */
> +} __packed;
> +
> +struct sack_edges {
> +       u32     l;
> +       u32     r;
> +} __packed;
> +
> +#define TCP_SACK_SIZE (sizeof(struct sack_edges))
> +
> +#define TCP_SACK_HILLS 4
> +
> +struct tcp_sack_v {
> +       u8      kind;                   /* 0x05                         */
> +       u8      len;                             /* Length              */
> +       struct  sack_edges hill[TCP_SACK_HILLS]; /* L & R widow edges   */
> +} __packed;
> +
> +struct tcp_t_opt {                     /* TCP time stamps option       */
> +       u8      kind;                   /* 0x08                         */
> +       u8      len;                    /* 0x0a                         */
> +       u32     t_snd;                  /* Sender timestamp             */
> +       u32     t_rcv;                  /* Receiver timestamp           */
> +} __packed;
> +
> +#define TCP_TSOPT_SIZE (sizeof(struct tcp_t_opt))
> +
> +/*
> + * ip tcp  structure with options
> + */
> +
> +struct ip_tcp_hdr_o {
> +       struct  ip_tcp_hdr      hdr;
> +       struct  tcp_mss         mss;
> +       struct  tcp_scale       scale;
> +       struct  tcp_sack_p      sack_p;
> +       struct  tcp_t_opt       t_opt;
> +       u8      end;
> +} __packed;
> +
> +#define IP_TCP_O_SIZE          (sizeof(struct ip_tcp_hdr_o))
> +
> +struct ip_tcp_hdr_s {
> +       struct  ip_tcp_hdr      hdr;
> +       struct  tcp_t_opt       t_opt;
> +       struct  tcp_sack_v      sack_v;
> +       u8      end;
> +} __packed;
> +
> +#define IP_TCP_SACK_SIZE       (sizeof(struct ip_tcp_hdr_s))
> +
> +/*
> + * TCP pseudo header definitions
> + */
> +#define PSEUDO_PAD_SIZE        8
> +
> +struct pseudo_hdr {
> +       u8 padding[PSEUDO_PAD_SIZE];    /* pseudo hdr size = ip_tcp hdr size */
> +       struct in_addr p_src;
> +       struct in_addr p_dst;
> +       u8      rsvd;
> +       u8      p;
> +       u16     len;
> +} __packed;
> +
> +#define PSEUDO_HDR_SIZE        (sizeof(struct pseudo_hdr)) - PSEUDO_PAD_SIZE
> +
> +/*
> + * union for building IP/TCP packet.
> + * build Pseudo header in packed buffer first, calculate TCP checksum
> + * then build IP header in packed  buffer.
> + */
> +
> +union tcp_build_pkt {
> +       struct pseudo_hdr ph;
> +       struct ip_tcp_hdr_o ip;
> +       struct ip_tcp_hdr_s sack;
> +       uchar  raw[1600];
> +} __packed;
> +
> +/*
> + * TCP STATE MACHINE STATES FOR SOCKET
> + */
> +
> +enum TCP_STATE {
> +       TCP_CLOSED,             /* Need to send SYN to connect            */
> +       TCP_SYN_SENT,           /* Trying to connect, waiting for SYN ACK */
> +       TCP_ESTABLISHED,        /* both server & client have a connection */
> +       TCP_CLOSE_WAIT,         /* Rec FIN, passed to app for FIN, ACK rsp*/
> +       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 */
> +};
> +
> +int tcp_find_in_buffer(uchar raw[], int payload_len, uchar field[],
> +                      int field_len);
> +void tcp_print_buffer(uchar raw[], int pkt_len, int payload_len,
> +                     int hdr_len, bool hide);
> +enum TCP_STATE tcp_get_tcp_state(void);
> +void tcp_set_tcp_state(enum TCP_STATE new_state);
> +int tcp_set_tcp_header(uchar *pkt, int dport, int sport, int payload_len,
> +                      u8 action, u32 tcp_seq_num, u32 tcp_ack_num);
> +
> +/*
> + * An incoming packet handler.
> + * @param pkt    pointer to the application packet
> + * @param dport  destination UDP port
> + * @param sip    source IP address
> + * @param sport  source UDP port
> + * @param len    packet length
> + */
> +typedef void rxhand_tcp(uchar *pkt, unsigned int dport,
> +                       struct in_addr sip, unsigned int sport,
> +                       unsigned int len);
> +void tcp_set_tcp_handler(rxhand_tcp *f);
> +
> +void rxhand_tcp_f(union tcp_build_pkt *b, unsigned int len);
> +
> +/*
> + * An incoming TCP packet handler for the TCP protocol.
> + * There is also a dynamic function pointer for TCP based commands to
> + * receive incoming traffic after the TCP protocol code has done its work.
> + */
> +
> +void rxhand_action(u8 tcp_action, int payload_len, u32 tcp_seq_num,
> +                  u32 tcp_ack_num, unsigned int pkt_len,
> +                  union tcp_build_pkt *b);
> diff --git a/net/Kconfig b/net/Kconfig
> index 143c4416cd..895b93dea9 100644
> --- a/net/Kconfig
> +++ b/net/Kconfig
> @@ -4,12 +4,12 @@
>
>  menuconfig NET
>         bool "Networking support"
> -       default y
>
>  if NET
>
>  config NET_RANDOM_ETHADDR
>         bool "Random ethaddr if unset"
> +       select LIB_RAND
>         help
>           Selecting this will allow the Ethernet interface to function
>           even when the ethaddr variable for that interface is unset.
> @@ -24,7 +24,6 @@ config NETCONSOLE
>
>  config NET_TFTP_VARS
>         bool "Control TFTP timeout and count through environment"
> -       depends on CMD_NET
>         default y
>         help
>           If set, allows controlling the TFTP timeout through the
> @@ -33,44 +32,22 @@ config NET_TFTP_VARS
>           If unset, timeout and maximum are hard-defined as 1 second
>           and 10 timouts per TFTP transfer.
>
> -config BOOTP_BOOTPATH
> -       bool "Enable BOOTP BOOTPATH"
> -       depends on CMD_NET
> -
> -config BOOTP_DNS
> -       bool "Enable bootp DNS"
> -       depends on CMD_NET
> -
> -config BOOTP_GATEWAY
> -       bool "Enable BOOTP gateway"
> -       depends on CMD_NET
> -
> -config BOOTP_HOSTNAME
> -       bool "Enable BOOTP hostname"
> -       depends on CMD_NET
> -
> -config BOOTP_PXE
> -       bool "Enable BOOTP PXE"
> -       depends on CMD_NET
> -
> -config BOOTP_SUBNETMASK
> -       bool "Enable BOOTP subnetmask"
> -       depends on CMD_NET
> -       depends on CMD_NET
> -
>  config BOOTP_PXE_CLIENTARCH
>         hex
> -       depends on CMD_NET
>          default 0x16 if ARM64
>          default 0x15 if ARM
>          default 0 if X86
>
>  config BOOTP_VCI_STRING
>         string
> -       depends on CMD_NET
>         default "U-Boot.armv7" if CPU_V7 || CPU_V7M
>         default "U-Boot.armv8" if ARM64
>         default "U-Boot.arm" if ARM
>         default "U-Boot"
>
> +config TCP
> +       bool "Include TCP for receiving files"
> +       help
> +         TCP support for receiving files.
> +
>  endif   # if NET
> diff --git a/net/Makefile b/net/Makefile
> index ae54eee5af..25729ebeeb 100644
> --- a/net/Makefile
> +++ b/net/Makefile
> @@ -25,7 +25,7 @@ obj-$(CONFIG_CMD_PING) += ping.o
>  obj-$(CONFIG_CMD_RARP) += rarp.o
>  obj-$(CONFIG_CMD_SNTP) += sntp.o
>  obj-$(CONFIG_CMD_NET)  += tftp.o
> -
> +obj-$(CONFIG_TCP)      += tcp.o
>  # Disable this warning as it is triggered by:
>  # sprintf(buf, index ? "foo%d" : "foo", index)
>  # and this is intentional usage.
> diff --git a/net/net.c b/net/net.c
> index df4e7317e7..7adc4b472c 100644
> --- a/net/net.c
> +++ b/net/net.c
> @@ -107,6 +107,9 @@
>  #if defined(CONFIG_CMD_SNTP)
>  #include "sntp.h"
>  #endif
> +#if defined(CONFIG_TCP)
> +#include <net/tcp.h>
> +#endif
>
>  DECLARE_GLOBAL_DATA_PTR;
>
> @@ -382,6 +385,9 @@ void net_init(void)
>
>                 /* Only need to setup buffer pointers once. */
>                 first_call = 0;
> +#if defined(CONFIG_TCP)
> +               tcp_set_tcp_state(TCP_CLOSED);
> +#endif
>         }
>
>         net_init_loop();
> @@ -781,11 +787,22 @@ int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport, int sport,
>                         int payload_len)
>  {
>         return net_send_ip_packet(ether, dest, dport, sport, payload_len,
> -                                 IPPROTO_UDP);
> +                                 IPPROTO_UDP, 0, 0, 0);
> +}
> +
> +#if defined(CONFIG_TCP)
> +int net_send_tcp_packet(int payload_len, int dport, int sport, u8 action,
> +                       u32 tcp_seq_num, u32 tcp_ack_num)
> +{
> +       return net_send_ip_packet(net_server_ethaddr, net_server_ip, dport,
> +                                 sport, payload_len, IPPROTO_TCP, action,
> +                                 tcp_seq_num, tcp_ack_num);
>  }
> +#endif
>
>  int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
> -                      int payload_len, int proto)
> +                      int payload_len, int proto, u8 action, u32 tcp_seq_num,
> +                      u32 tcp_ack_num)
>  {
>         uchar *pkt;
>         int eth_hdr_size;
> @@ -794,6 +811,13 @@ int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
>                 debug_cond(DEBUG_DEV_PKT,
>                            "UDP Send  (to=%pI4, from=%pI4, len=%d)\n",
>                            &dest, &net_ip, payload_len);
> +#if defined(CONFIG_TCP)
> +
> +       } else {
> +               debug_cond(DEBUG_DEV_PKT,
> +                          "TCP Send  (%pI4, %pI4, len=%d, A=%x)\n",
> +                          &dest, &net_ip, payload_len, action);
> +#endif
>         }
>
>         /* make sure the net_tx_packet is initialized (net_init() was called) */
> @@ -812,15 +836,19 @@ int net_send_ip_packet(uchar *ether, struct in_addr dest, int dport, int sport,
>         pkt = (uchar *)net_tx_packet;
>
>         eth_hdr_size = net_set_ether(pkt, ether, PROT_IP);
> -       switch (proto) {
> -       case IPPROTO_UDP:
> +       if (proto == IPPROTO_UDP) {
>                 net_set_udp_header(pkt + eth_hdr_size, dest,
>                                    dport, sport, payload_len);
>                 pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
> -       break;
> -       default:
> -               return -1;
> +
> +#if defined(CONFIG_TCP)
> +       } else {
> +               pkt_hdr_size = eth_hdr_size +
> +               tcp_set_tcp_header(pkt + eth_hdr_size, dport, sport,
> +                                  payload_len, action,
> +                                  tcp_seq_num, tcp_ack_num);
>         }
> +#endif
>
>         /* if MAC address was not discovered yet, do an ARP request */
>         if (memcmp(ether, net_null_ethaddr, 6) == 0) {
> @@ -1225,6 +1253,15 @@ void net_process_received_packet(uchar *in_packet, int len)
>                 if (ip->ip_p == IPPROTO_ICMP) {
>                         receive_icmp(ip, len, src_ip, et);
>                         return;
> +#if defined(CONFIG_TCP)
> +               } else if (ip->ip_p == IPPROTO_TCP) {
> +                       debug_cond(DEBUG_DEV_PKT,
> +                                  "TCP PH (to=%pI4, from=%pI4, len=%d)\n",
> +                                  &dst_ip, &src_ip, len);
> +
> +                               rxhand_tcp_f((union tcp_build_pkt *)ip, len);
> +                       return;
> +#endif
>                 } else if (ip->ip_p != IPPROTO_UDP) {   /* Only UDP packets */
>                         return;
>                 }
> diff --git a/net/tcp.c b/net/tcp.c
> new file mode 100644
> index 0000000000..612a6a4b7d
> --- /dev/null
> +++ b/net/tcp.c
> @@ -0,0 +1,749 @@
> +/*
> + *     Copyright 2017 Duncan Hare, all rights reserved.
> + *     SPDX-License-Identifier:        GPL-2.0
> + */
> +
> +/*
> + * General Desription:
> + *
> + * TCP support for the wget command, for fast file downloading.
> + *
> + * HTTP/TCP Receiver:
> + *
> + *      Prequeisites:   - own ethernet address
> + *                      - own IP address
> + *                      - Server IP address
> + *                      - Server with TCP
> + *                      - TCP application (eg wget)
> + *      Next Step       HTTPS?
> + */
> +#include <common.h>
> +#include <command.h>
> +#include <console.h>
> +#include <environment.h>
> +#include <errno.h>
> +#include <net.h>
> +#include <net/tcp.h>
> +#if defined(CONFIG_CMD_WGET)
> +#include "net/wget.h"
> +#endif
> +
> +/*
> + * TCP sliding window  control
> + * used by us to request re-TX
> + */
> +
> +static struct tcp_sack_v tcp_lost;
> +
> +/* TCP option timestamp */
> +static u32 loc_timestamp;
> +static u32 rmt_timestamp;
> +
> +u32 tcp_seq_init;
> +u32 tcp_ack_edge;
> +u32 tcp_seq_max;
> +
> +int tcp_activity_count;
> +
> +/*
> + * Search for TCP_SACK and review the
> + * comments before the code section
> + * TCP_SACK is the number of packets
> + * at the front of the stream
> + */
> +
> +enum pkt_state {PKT, NOPKT};
> +struct sack_r {
> +       struct sack_edges se;
> +       enum   pkt_state st;
> +};
> +
> +struct sack_r edge_a[TCP_SACK];
> +unsigned int sack_idx;
> +unsigned int prev_len;
> +
> +/* TCP connection state */
> +static enum TCP_STATE tcp_state;
> +
> +/*
> + * An incoming TCP packet handler for the TCP protocol.
> + * There is also a dymanic function pointer for TCP based commads to
> + * receive incoming traffic after the TCP protocol code has done its work.
> + */
> +
> +/* Current TCP RX packet handler */
> +static rxhand_tcp *tcp_packet_handler;
> +
> +enum TCP_STATE tcp_get_tcp_state(void)
> +{
> +       return tcp_state;
> +}
> +
> +void tcp_set_tcp_state(enum TCP_STATE new_state)
> +{
> +       tcp_state = new_state;
> +}
> +
> +void tcp_print_buffer(uchar raw[], int pkt_len, int payload_len,
> +                     int hdr_len, bool hide)
> +{
> +       int i;
> +
> +       for (i = pkt_len - payload_len; i < pkt_len; i++) {
> +               if (i <= hdr_len)
> +                       printf("%02X", raw[i]);
> +               else if ((raw[i] > 0x19) && (raw[i] < 0x7f))
> +                       putc(raw[i]);
> +               else if (hide == 0)
> +                       putc(raw[i]);
> +               else
> +                       printf("%02X", raw[i]);
> +       }
> +       printf("%s", "\n");
> +}
> +
> +int tcp_find_in_buffer(uchar raw[], int payload_len, uchar field[],
> +                      int field_len)
> +{
> +       int i, j;
> +
> +       for (i = 0; i < payload_len; i++) {
> +               if (raw[i] == field[0]) {
> +                       for (j = 1; j < field_len; j++) {
> +                               if (raw[i + j] != field[j])
> +                                       break;
> +                       if (j == field_len)
> +                               return i;
> +                       }
> +               }
> +       }
> +       return 0;
> +}
> +
> +static void dummy_handler(uchar *pkt, unsigned int dport,
> +                         struct in_addr sip, unsigned int sport,
> +                         unsigned int len)
> +{
> +}
> +
> +void tcp_set_tcp_handler(rxhand_tcp *f)
> +{
> +       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;
> +}
> +
> +u16 tcp_set_pseudo_header(uchar *pkt, struct in_addr src, struct in_addr dest,
> +                         int tcp_len, int pkt_len)
> +{
> +       union tcp_build_pkt *b = (union tcp_build_pkt *)pkt;
> +       int checksum_len;
> +
> +       /*
> +        * Pseudo header
> +        *
> +        * Zero the byte after the last byte so that the header checksum
> +        * will always work.
> +        */
> +
> +       pkt[pkt_len] = 0x00;
> +
> +       net_copy_ip((void *)&b->ph.p_src, &src);
> +       net_copy_ip((void *)&b->ph.p_dst, &dest);
> +       b->ph.rsvd      = 0x00;
> +       b->ph.p         = IPPROTO_TCP;
> +       b->ph.len       = htons(tcp_len);
> +       checksum_len    = tcp_len + PSEUDO_HDR_SIZE;
> +
> +       debug_cond(DEBUG_DEV_PKT,
> +                  "TCP Pesudo  Header  (to=%pI4, from=%pI4, Len=%d)\n",
> +                  &b->ph.p_dst, &b->ph.p_src, checksum_len);
> +
> +       return compute_ip_checksum(pkt + PSEUDO_PAD_SIZE, checksum_len);
> +}
> +
> +int net_set_ack_options(union tcp_build_pkt *b)
> +{
> +       b->sack.hdr.tcp_hlen  = (TCP_HDR_SIZE >> 2) << 4;
> +
> +       b->sack.t_opt.kind              = TCP_O_TS;
> +       b->sack.t_opt.len               = TCP_OPT_LEN_A;
> +       b->sack.t_opt.t_snd             = htons(loc_timestamp);
> +       b->sack.t_opt.t_rcv             = rmt_timestamp;
> +       b->sack.sack_v.kind             = 0x01;
> +       b->sack.sack_v.len              = 0x00;
> +
> +       if (tcp_lost.len > TCP_OPT_LEN_2) {
> +               debug_cond(DEBUG_DEV_PKT, "TCP ack opt lost.len %x\n",
> +                          tcp_lost.len);
> +               b->sack.sack_v.len              = tcp_lost.len;
> +               b->sack.sack_v.kind             = TCP_V_SACK;
> +               b->sack.sack_v.hill[0].l = htonl(tcp_lost.hill[0].l);
> +               b->sack.sack_v.hill[0].r = htonl(tcp_lost.hill[0].r);
> +
> +               /*
> +                * These SACK structures are initialized with NOPs to
> +                * provide TCP header alignment padding. There are 4
> +                * SACK structures used for both header padding and
> +                * internally.
> +                */
> +
> +               b->sack.sack_v.hill[1].l = htonl(tcp_lost.hill[1].l);
> +               b->sack.sack_v.hill[1].r = htonl(tcp_lost.hill[1].r);
> +               b->sack.sack_v.hill[2].l = htonl(tcp_lost.hill[2].l);
> +               b->sack.sack_v.hill[2].r = htonl(tcp_lost.hill[2].r);
> +               b->sack.sack_v.hill[3].l = TCP_O_NOP;
> +               b->sack.sack_v.hill[3].r = TCP_O_NOP;
> +       }
> +
> +       /*
> +       * TCP lengths are stored as a rounded up number of 32 bit words
> +       * Add 3 to length round up, rounded, then divided into the length
> +       * in 32 bit words.
> +       */
> +
> +       b->sack.hdr.tcp_hlen = (((TCP_HDR_SIZE + TCP_TSOPT_SIZE
> +                               + tcp_lost.len + 3)  >> 2) << 4);
> +
> +       /*
> +        * This returns the actual rounded up length of the
> +        * TCP header to add to the total packet length
> +       */
> +
> +       return b->sack.hdr.tcp_hlen >> 2;
> +}
> +
> +void net_set_syn_options(union tcp_build_pkt *b)
> +{
> +       tcp_lost.len            = 0;
> +       b->ip.hdr.tcp_hlen      = 0xa0;
> +
> +       b->ip.mss.kind          = TCP_O_MSS;
> +       b->ip.mss.len           = TCP_OPT_LEN_4;
> +       b->ip.mss.mss           = htons(TCP_MSS);
> +       b->ip.scale.kind        = TCP_O_SCL;
> +       b->ip.scale.scale       = TCP_SCALE;
> +       b->ip.scale.len         = TCP_OPT_LEN_3;
> +       b->ip.sack_p.kind       = TCP_P_SACK;
> +       b->ip.sack_p.len        = TCP_OPT_LEN_2;
> +       b->ip.t_opt.kind        = TCP_O_TS;
> +       b->ip.t_opt.len         = TCP_OPT_LEN_A;
> +       loc_timestamp           = get_ticks() % 3072;
> +       rmt_timestamp           = 0x00000000;
> +       b->ip.t_opt.t_snd       = 0;
> +       b->ip.t_opt.t_rcv       = 0x00000000;
> +       b->ip.end               = TCP_O_END;
> +}
> +
> +int tcp_set_tcp_header(uchar *pkt, int dport, int sport, int payload_len,
> +                      u8 action, u32 tcp_seq_num, u32 tcp_ack_num)
> +{
> +       union tcp_build_pkt *b = (union tcp_build_pkt *)pkt;
> +       int     pkt_hdr_len;
> +       int     pkt_len;
> +       int     tcp_len;
> +
> +       b->ip.hdr.tcp_flags     = action;
> +       pkt_hdr_len             = IP_TCP_HDR_SIZE;
> +       b->ip.hdr.tcp_hlen      = 0x50;         /* Header is 5 32 bit words  */
> +                                               /* 4 bits TCP header Length/4*/
> +                                               /* 4 bits Reserved           */
> +                                               /* For options               */
> +       switch (action) {
> +       case TCP_SYN:
> +               debug_cond(DEBUG_DEV_PKT,
> +                          "TCP Hdr:SYN (%pI4, %pI4, sq=%d, ak=%d)\n",
> +                          &net_server_ip, &net_ip,
> +                          tcp_seq_num, tcp_ack_num);
> +               tcp_activity_count = 0;
> +               net_set_syn_options(b);
> +               tcp_seq_num = 0;
> +               tcp_ack_num = 0;
> +               pkt_hdr_len = IP_TCP_O_SIZE;
> +               if (tcp_state == TCP_SYN_SENT) {  /* Too many sins */
> +                       action    = TCP_FIN;
> +                       tcp_state = TCP_FIN_WAIT_1;
> +               } else {
> +                       tcp_state = TCP_SYN_SENT;
> +               }
> +       break;
> +       case TCP_ACK:
> +               pkt_hdr_len         = IP_HDR_SIZE +
> +                                     net_set_ack_options(b);
> +               b->ip.hdr.tcp_flags = action;
> +               debug_cond(DEBUG_DEV_PKT,
> +                          "TCP Hdr:ACK (%pI4, %pI4, s=%d, a=%d, A=%x)\n",
> +                          &net_server_ip, &net_ip, tcp_seq_num, tcp_ack_num,
> +                          action);
> +       break;
> +       case TCP_FIN:
> +               debug_cond(DEBUG_DEV_PKT,
> +                          "TCP Hdr:FIN  (%pI4, %pI4, s=%d, a=%d)\n",
> +                          &net_server_ip, &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;
> +
> +       /* 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;
> +               tcp_ack_edge++;
> +               debug_cond(DEBUG_DEV_PKT,
> +                          "TCP Hdr:FIN ACK PSH(%pI4, %pI4, s=%d, a=%d, A=%x)\n",
> +                          &net_server_ip, &net_ip,
> +                          tcp_seq_num, tcp_ack_edge, action);
> +                                       /* FALLTHRU */
> +       default:
> +               pkt_hdr_len         = IP_HDR_SIZE +
> +                                     net_set_ack_options(b);
> +               b->ip.hdr.tcp_flags = action | TCP_PUSH | TCP_ACK;
> +               debug_cond(DEBUG_DEV_PKT,
> +                          "TCP Hdr:dft  (%pI4, %pI4, s=%d, a=%d, A=%x)\n",
> +                          &net_server_ip, &net_ip,
> +                          tcp_seq_num, tcp_ack_num, action);
> +       }
> +
> +       pkt_len = pkt_hdr_len + payload_len;
> +       tcp_len = pkt_len - IP_HDR_SIZE;
> +
> +       /* TCP Header */
> +       b->ip.hdr.tcp_ack       = htonl(tcp_ack_edge);
> +       b->ip.hdr.tcp_src       = htons(sport);
> +       b->ip.hdr.tcp_dst       = htons(dport);
> +       b->ip.hdr.tcp_seq       = htonl(tcp_seq_num);
> +       tcp_seq_num             = tcp_seq_num + payload_len;
> +
> +       /*
> +        * TCP window size - TCP header variable tcp_win.
> +        * Change tcp_win only if you have an understanding of network
> +        * overrun, congestion, TCP segment sizes, TCP windows, TCP scale,
> +        * queuing theory  and packet buffering. If there are too few buffers,
> +        * there will be data loss, recovery may work or the sending TCP,
> +        * the server, could abort the stream transmission.
> +        * MSS is governed by maximum Ethernet frame length.
> +        * The number of buffers is governed by the desire to have a queue of
> +        * full buffers to be processed at the destination to maximize
> +        * throughput. Temporary memory use for the boot phase on modern
> +        * SOCs is may not be considered a constraint to buffer space, if
> +        * 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_xsum      = 0x0000;
> +       b->ip.hdr.tcp_ugr       = 0x0000;
> +
> +       b->ip.hdr.tcp_xsum = tcp_set_pseudo_header(pkt, net_ip, net_server_ip,
> +                                                  tcp_len, pkt_len);
> +
> +       /*
> +        * IP Header
> +        */
> +
> +       net_set_ip_header((uchar *)&b->ip, net_server_ip, net_ip,
> +                         pkt_len, IPPROTO_TCP);
> +
> +       return pkt_hdr_len;
> +}
> +
> +/*
> + * Selective Acknowledgment (Essential for fast stream transfer)
> + *
> + * Before modifying this section of code, which the author found difficult
> + * to write, please be familiar with the SACK (Selective Acknowledgment) RFCs.
> + */
> +
> +void tcp_hole(u32 tcp_seq_num, u32 len, u32 tcp_seq_max)
> +{
> +       unsigned int idx_sack;
> +       unsigned int sack_end = TCP_SACK - 1;
> +       unsigned int sack_in;
> +       unsigned int hill = 0;
> +       enum pkt_state expect = PKT;
> +
> +       u32 seq   = tcp_seq_num - tcp_seq_init;
> +       u32 hol_l = tcp_ack_edge - tcp_seq_init;
> +       u32 hol_r = 0;
> +
> +       /* Place seq number in correct place */
> +
> +       if (prev_len == 0)
> +               prev_len = len;
> +       idx_sack = sack_idx + ((tcp_seq_num - tcp_ack_edge) / prev_len);
> +       if (idx_sack < TCP_SACK) {
> +               edge_a[idx_sack].se.l = tcp_seq_num;
> +               edge_a[idx_sack].se.r = tcp_seq_num + len;
> +               edge_a[idx_sack].st   = PKT;
> +
> +               /* The fin (last) packet is not the same length as data packets,
> +                * and if it's length is recorded and used for array index
> +                * the array index calculations break.
> +                */
> +               if (prev_len < len)
> +                       prev_len = len;
> +       }
> +
> +       debug_cond(DEBUG_DEV_PKT,
> +                  "TCP 1 seq %d, edg %d, len %d, sack_idx %d, sack_end %d\n",
> +                   seq, hol_l, len, sack_idx, sack_end);
> +
> +       /* Right edge of contiguous stream, is the left edge of first hill */
> +
> +       hol_l = tcp_seq_num - tcp_seq_init;
> +       hol_r = hol_l + len;
> +
> +       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");
> +                                       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++;
> +                                       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 (hill < TCP_SACK_HILLS)
> +                                               tcp_lost.hill[hill].r =
> +                                                       edge_a[sack_in].se.r;
> +                               if (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 (tcp_lost.len <= TCP_OPT_LEN_2)
> +               sack_idx = 0;
> +}
> +
> +void tcp_parse_options(uchar *o, int o_len)
> +{
> +       struct tcp_t_opt  *tsopt;
> +       uchar *p = o;
> +
> +       for (p = o; p < (o + o_len); p = p + p[1]) {
> +               if (p[1] != 0) {
> +                       switch (p[0]) {
> +                       case TCP_O_END:
> +                               return;
> +                       case TCP_O_MSS:
> +                       break;
> +                       case TCP_O_SCL:
> +                       break;
> +                       case TCP_P_SACK:
> +                       break;
> +                       case TCP_V_SACK:
> +                       break;
> +                       case TCP_O_TS:
> +                               tsopt = (struct tcp_t_opt *)p;
> +                               rmt_timestamp = tsopt->t_snd;
> +                               return;
> +                       break;
> +                       }
> +                       if (p[0] == TCP_O_NOP)
> +                               p++;
> +               } else {
> +                       return;
> +               }
> +       }
> +}
> +
> +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;
> +               tcp_state = TCP_CLOSED;
> +               net_set_state(NETLOOP_FAIL);
> +               debug_cond(DEBUG_INT_STATE, "TCP Reset %x\n", tcp_flags);
> +               return TCP_RST;
> +       }
> +
> +       switch  (tcp_state) {
> +       case TCP_CLOSED:
> +       debug_cond(DEBUG_INT_STATE, "TCP CLOSED %x\n", tcp_flags);
> +               if (tcp_fin)
> +                       action = TCP_DATA;
> +               if (tcp_syn)
> +                       action = TCP_RST;
> +               if (tcp_ack)
> +                       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;
> +                       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;
> +                               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) && (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;
> +               }
> +               if (tcp_push)
> +                       action = action | TCP_PUSH;
> +               if (tcp_syn)
> +                       action = TCP_ACK + TCP_RST;
> +       break;
> +       case TCP_CLOSE_WAIT:
> +               debug_cond(DEBUG_INT_STATE, "TCP_CLOSE_WAIT (%x)\n", tcp_flags);
> +               action = TCP_DATA;                      /* Wait for app */
> +       break;
> +       case TCP_FIN_WAIT_2:
> +               debug_cond(DEBUG_INT_STATE, "TCP_FIN_WAIT_2 (%x)\n", tcp_flags);
> +               if (tcp_fin)
> +                       action =  TCP_DATA;
> +               if (tcp_syn)
> +                       action =  TCP_DATA;
> +               if (tcp_ack) {
> +                       action =  TCP_PUSH | TCP_ACK;
> +                       tcp_state = TCP_CLOSED;
> +                       puts("\n");
> +               }
> +       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;
> +                        tcp_state = TCP_FIN_WAIT_2;
> +               }
> +               if (tcp_syn)
> +                       action =  TCP_RST;
> +               if (tcp_ack) {
> +                       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_fin)
> +                       action = TCP_DATA;
> +               if (tcp_syn)
> +                       action = TCP_RST;
> +               if (tcp_ack) {
> +                       action = TCP_PUSH;
> +                       tcp_state = TCP_CLOSED;
> +                       puts("\n");
> +               }
> +       break;
> +       }
> +       return action;
> +}
> +
> +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;
> +       u32 tcp_ack_num;
> +       struct in_addr action_and_state;
> +
> +       int tcp_hdr_len;
> +       int 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);
> +
> +               debug_cond(DEBUG_DEV_PKT,
> +                          "In__________________________________________\n");
> +
> +       b->ip.hdr.ip_src        = net_server_ip;
> +       b->ip.hdr.ip_dst        = net_ip;
> +       b->ip.hdr.ip_sum        = 0x0000;
> +       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 = 0x0000;
> +       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 = (b->ip.hdr.tcp_hlen >> 2);
> +       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);
> +
> +       /*
> +        * Sent first packet send from server as first to app
> +        * Other packets could be ordered, but are currently not ordered.
> +        */
> +
> +       tcp_action  = tcp_state_machine(b->ip.hdr.tcp_flags,
> +                                       &tcp_seq_num, payload_len);
> +
> +       /*
> +        * State altering command to be sent.
> +        * The packet sequence and ack numbers are in the tcp_seq_num
> +        * and tcp_ack_num variables. The current packet, its position
> +        * in the data stream, is the in the range of those variables.
> +        *
> +        * In the "application push" invocation, the TCP header with all
> +        * its information is pointed to by the packet pointer.
> +        *
> +        * in the typedef
> +        *      void rxhand_tcp(uchar *pkt, unsigned int dport,
> +        *                      struct in_addr sip, unsigned int sport,
> +        *                      unsigned int len);
> +        * *pkt is the pointer to the payload
> +        * dport is used for tcp_seg_num
> +        * action_and_state.s_addr is used for TCP state
> +        * sport is used for tcp_ack_num (which is unused by the app)
> +        * pkt_ length is the payload length.
> +        *
> +        * TCP_PUSH from the state machine with a payload length of 0 is a
> +        * connect or disconnect event
> +        */
> +
> +       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 Seq & Ack  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);
> +       }
> +}
> --
> 2.11.0
>
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> https://lists.denx.de/listinfo/u-boot

[U-Boot] [PATCH v7 3/4] Integrating TCP and wget into u-boot

[DH at synoia.com]

From: Duncan Hare <DuncanCHare@yahoo.com>

All the code is new, and not copied from any source.

>>>>>
<<<<

Commit-notes
Integrating TCP and wget into u-boot

All the code is new, and not copied from any source.

>>>>>
<<<<

Commit-notes

Why http and wget:

HTTP is the most efficient file retrieval protocol in common
use. The client send a single request, after TCP connection,
to receive a file of any length.

WGET is the application which implements http file transfer
outside browsers as a file transfer protocol. Versions of
wget exists on many operating systems.
Integrating TCP and wget into u-boot

All the code is new, and not copied from any source.

>>>>>
Integrating TCP and wget into u-boot

<<<<

Commit-notes

Why http and wget:

HTTP is the most efficient file retrieval protocol in common
use. The client send a single request, after TCP connection,
to receive a file of any length.

WGET is the application which implements http file transfer
outside browsers as a file transfer protocol. Versions of
wget exists on many operating systems.

END

Signed-off-by: Duncan Hare <DuncanCHare@yahoo.com>
---

Changes in v7:
Integrating TCP and wget into u-boot
Integrating TCP and wget into u-boot

 cmd/Kconfig        |  93 ++----------
 cmd/net.c          |  13 ++
 include/net/wget.h |  17 +++
 net/Makefile       |   1 +
 net/wget.c         | 419 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 466 insertions(+), 77 deletions(-)
 create mode 100644 include/net/wget.h
 create mode 100644 net/wget.c

diff --git a/cmd/Kconfig b/cmd/Kconfig
index 136836d146..46b489a966 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -23,29 +23,6 @@ config HUSH_PARSER
 	  If disabled, you get the old, much simpler behaviour with a somewhat
 	  smaller memory footprint.
 
-config CMDLINE_EDITING
-	bool "Enable command line editing"
-	depends on CMDLINE
-	default y
-	help
-	  Enable editing and History functions for interactive command line
-	  input operations
-
-config AUTO_COMPLETE
-	bool "Enable auto complete using TAB"
-	depends on CMDLINE
-	default y
-	help
-	  Enable auto completion of commands using TAB.
-
-config SYS_LONGHELP
-	bool "Enable long help messages"
-	depends on CMDLINE
-	default y if CMDLINE
-	help
-	  Defined when you want long help messages included
-	  Do not set this option when short of memory.
-
 config SYS_PROMPT
 	string "Shell prompt"
 	default "=> "
@@ -331,12 +308,6 @@ config CMD_SPL_WRITE_SIZE
 	  flash used by Falcon-mode boot. See the documentation until CMD_SPL
 	  for detail.
 
-config CMD_FITUPD
-	bool "fitImage update command"
-	help
-	  Implements the 'fitupd' command, which allows to automatically
-	  store software updates present on a TFTP server in NOR Flash
-
 config CMD_THOR_DOWNLOAD
 	bool "thor - TIZEN 'thor' download"
 	help
@@ -426,7 +397,6 @@ menu "Memory commands"
 config CMD_CRC32
 	bool "crc32"
 	select HASH
-	default n if ARCH_SUNXI
 	default y
 	help
 	  Compute CRC32.
@@ -568,7 +538,6 @@ config CMD_LZMADEC
 
 config CMD_UNZIP
 	bool "unzip"
-	default n if ARCH_SUNXI
 	default y if CMD_BOOTI
 	help
 	  Uncompress a zip-compressed memory region.
@@ -611,7 +580,7 @@ config CMD_DEMO
 
 config CMD_DFU
 	bool "dfu"
-	select DFU
+	select USB_FUNCTION_DFU
 	help
 	  Enables the command "dfu" which is used to have U-Boot create a DFU
 	  class device via USB. This command requires that the "dfu_alt_info"
@@ -645,7 +614,6 @@ config CMD_FLASH
 
 config CMD_FPGA
 	bool "fpga"
-	depends on FPGA
 	default y
 	help
 	  FPGA support.
@@ -701,7 +669,6 @@ config CMD_GPT
 	bool "GPT (GUID Partition Table) command"
 	select PARTITION_UUIDS
 	select EFI_PARTITION
-	select HAVE_BLOCK_DEVICE
 	imply RANDOM_UUID
 	help
 	  Enable the 'gpt' command to ready and write GPT style partition
@@ -709,7 +676,6 @@ config CMD_GPT
 
 config RANDOM_UUID
 	bool "GPT Random UUID generation"
-	select LIB_UUID
 	help
 	  Enable the generation of partitions with random UUIDs if none
 	  are provided.
@@ -780,14 +746,12 @@ config CMD_I2C
 
 config CMD_LOADB
 	bool "loadb"
-	default n if ARCH_SUNXI
 	default y
 	help
 	  Load a binary file over serial line.
 
 config CMD_LOADS
 	bool "loads"
-	default n if ARCH_SUNXI
 	default y
 	help
 	  Load an S-Record file over serial line
@@ -849,7 +813,6 @@ config CMD_ONENAND
 config CMD_PART
 	bool "part"
 	select PARTITION_UUIDS
-	select HAVE_BLOCK_DEVICE
 	help
 	  Read and display information about the partition table on
 	  various media.
@@ -900,15 +863,6 @@ config CMD_SAVES
 	  Provides a way to save a binary file using the Motorola S-Record
 	  format over the serial line.
 
-config CMD_SCSI
-	bool "scsi - Access to SCSI devices"
-	default y if SCSI
-	help
-	  This provides a 'scsi' command which provides access to SCSI (Small
-	  Computer System Interface) devices. The command provides a way to
-	  scan the bus, reset the bus, read and write data and get information
-	  about devices.
-
 config CMD_SDRAM
 	bool "sdram - Print SDRAM configuration information"
 	help
@@ -951,7 +905,6 @@ config CMD_UNIVERSE
 
 config CMD_USB
 	bool "usb"
-	select HAVE_BLOCK_DEVICE
 	help
 	  USB support.
 
@@ -961,18 +914,9 @@ config CMD_USB_SDP
 	help
 	  Enables the command "sdp" which is used to have U-Boot emulating the
 	  Serial Download Protocol (SDP) via USB.
-config CMD_ROCKUSB
-	bool "rockusb"
-	depends on USB_FUNCTION_ROCKUSB
-	help
-          Rockusb protocol is widely used by Rockchip SoC based devices. It can
-	  read/write info, image to/from devices. This enable rockusb command
-	  support to communication with rockusb device. for more detail about
-	  this command, please read doc/README.rockusb.
 
 config CMD_USB_MASS_STORAGE
 	bool "UMS usb mass storage"
-	select USB_FUNCTION_MASS_STORAGE
 	help
 	  USB mass storage support
 
@@ -1012,10 +956,9 @@ endmenu
 
 menu "Network commands"
 
-if NET
-
 config CMD_NET
 	bool "bootp, tftpboot"
+        select NET
 	default y
 	help
 	  Network commands.
@@ -1039,13 +982,11 @@ config CMD_RARP
 
 config CMD_DHCP
 	bool "dhcp"
-	depends on CMD_NET
 	help
 	  Boot image via network using DHCP/TFTP protocol
 
 config CMD_PXE
 	bool "pxe"
-	depends on CMD_NET
 	select MENU
 	help
 	  Boot image via network using PXE protocol
@@ -1094,7 +1035,11 @@ config CMD_ETHSW
 	  operations such as enabling / disabling a port and
 	  viewing/maintaining the filtering database (FDB)
 
-endif
+config CMD_WGET
+	bool "wget"
+	select TCP
+	help
+	  Download a kernel, or other files, from a web server over TCP.
 
 endmenu
 
@@ -1187,7 +1132,6 @@ config CMD_GETTIME
 # TODO: rename to CMD_SLEEP
 config CMD_MISC
 	bool "sleep"
-	default n if ARCH_SUNXI
 	default y
 	help
 	  Delay execution for some time
@@ -1227,7 +1171,6 @@ config CMD_TERMINAL
 
 config CMD_UUID
 	bool "uuid, guid - generation of unique IDs"
-	select LIB_UUID
 	help
 	  This enables two commands:
 
@@ -1239,8 +1182,6 @@ config CMD_UUID
 
 endmenu
 
-source "cmd/ti/Kconfig"
-
 config CMD_BOOTSTAGE
 	bool "Enable the 'bootstage' command"
 	depends on BOOTSTAGE
@@ -1422,20 +1363,17 @@ config CMD_CRAMFS
 
 config CMD_EXT2
 	bool "ext2 command support"
-	select FS_EXT4
 	help
 	  Enables EXT2 FS command
 
 config CMD_EXT4
 	bool "ext4 command support"
-	select FS_EXT4
 	help
 	  Enables EXT4 FS command
 
 config CMD_EXT4_WRITE
 	depends on CMD_EXT4
 	bool "ext4 write command support"
-	select EXT4_WRITE
 	help
 	  Enables EXT4 FS write command
 
@@ -1503,6 +1441,15 @@ config CMD_REISER
 	    reiserls - list files
 	    reiserload - load a file
 
+config CMD_SCSI
+	bool "scsi - Access to SCSI devices"
+	default y if SCSI
+	help
+	  This provides a 'scsi' command which provides access to SCSI (Small
+	  Computer System Interface) devices. The command provides a way to
+	  scan the bus, reset the bus, read and write data and get information
+	  about devices.
+
 config CMD_YAFFS2
 	bool "yaffs2 - Access of YAFFS2 filesystem"
 	depends on YAFFS2
@@ -1561,14 +1508,6 @@ config CMD_KGDB
 	  single-stepping, inspecting variables, etc. This is supported only
 	  on PowerPC at present.
 
-config CMD_LOG
-	bool "log - Generation, control and access to logging"
-	help
-	  This provides access to logging features. It allows the output of
-	  log data to be controlled to a limited extent (setting up the default
-	  maximum log level for emitting of records). It also provides access
-	  to a command used for testing the log system.
-
 config CMD_TRACE
 	bool "trace - Support tracing of function calls and timing"
 	help
diff --git a/cmd/net.c b/cmd/net.c
index d7c776aacf..6a7a51f357 100644
--- a/cmd/net.c
+++ b/cmd/net.c
@@ -110,6 +110,19 @@ U_BOOT_CMD(
 );
 #endif
 
+#if defined(CONFIG_CMD_WGET)
+static int do_wget(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	return netboot_common(WGET, cmdtp, argc, argv);
+}
+
+U_BOOT_CMD(
+	wget,	3,	1,	do_wget,
+	"boot image via network using HTTP protocol",
+	"[loadAddress] [[hostIPaddr:]path and image name]"
+);
+#endif
+
 static void netboot_update_env(void)
 {
 	char tmp[22];
diff --git a/include/net/wget.h b/include/net/wget.h
new file mode 100644
index 0000000000..dce16c573d
--- /dev/null
+++ b/include/net/wget.h
@@ -0,0 +1,17 @@
+/*
+ * Duncan Hare Copyright 2017
+ */
+
+void wget_start(void);			/* Begin wget */
+
+enum WGET_STATE {
+	WGET_CLOSED,
+	WGET_CONNECTING,
+	WGET_CONNECTED,
+	WGET_TRANSFERRING,
+	WGET_TRANSFERRED};
+
+#define	DEBUG_WGET		0	/* Set to 1 for debug messges */
+#define	SERVER_PORT		80
+#define	WGET_RETRY_COUNT	30
+#define	WGET_TIMEOUT		2000UL
diff --git a/net/Makefile b/net/Makefile
index 25729ebeeb..f83df5b728 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_CMD_RARP) += rarp.o
 obj-$(CONFIG_CMD_SNTP) += sntp.o
 obj-$(CONFIG_CMD_NET)  += tftp.o
 obj-$(CONFIG_TCP)      += tcp.o
+obj-$(CONFIG_CMD_WGET) += wget.o
 # Disable this warning as it is triggered by:
 # sprintf(buf, index ? "foo%d" : "foo", index)
 # and this is intentional usage.
diff --git a/net/wget.c b/net/wget.c
new file mode 100644
index 0000000000..f7923e35c8
--- /dev/null
+++ b/net/wget.c
@@ -0,0 +1,419 @@
+/*
+ * WGET/HTTP support driver based on U-BOOT's nfs.c
+ * Copyright Duncan Hare <dh@synoia.com> 2017
+ * SPDX-License-Identifier:GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <mapmem.h>
+#include <net.h>
+#include <net/wget.h>
+#include <net/tcp.h>
+
+const char bootfile1[]   = "GET ";
+const  char bootfile3[]   = " HTTP/1.0\r\n\r\n";
+const char http_eom[]     = "\r\n\r\n";
+const char http_ok[]      = "200";
+const char content_len[]  = "Content-Length";
+const char linefeed[]     = "\r\n";
+static struct in_addr web_server_ip;
+static int our_port;
+static int wget_timeout_count;
+
+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.
+ */
+
+static struct pkt_qd pkt_q[PKTBUFSRX / 4];
+static int pkt_q_idx;
+static unsigned long content_length;
+static unsigned int packets;
+
+static unsigned int initial_data_seq_num;
+
+static enum  WGET_STATE wget_state;
+
+static char *image_url;
+static unsigned int wget_timeout = WGET_TIMEOUT;
+
+static void  wget_timeout_handler(void);
+
+static enum net_loop_state wget_loop_state;
+
+/* Timeout retry parameters */
+static u8 r_action;
+static unsigned int r_tcp_ack_num;
+static unsigned int r_tcp_seq_num;
+static int r_len;
+
+static inline int store_block(uchar *src, unsigned int offset, unsigned int len)
+{
+	ulong newsize = offset + len;
+	uchar *ptr;
+
+#ifdef CONFIG_SYS_DIRECT_FLASH_WGET
+	int i, rc = 0;
+
+	for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; i++) {
+		/* start address in flash? */
+		if (load_addr + offset >= flash_info[i].start[0]) {
+			rc = 1;
+			break;
+		}
+	}
+
+	if (rc) { /* Flash is destination for this packet */
+		rc = flash_write((uchar *)src,
+				 (ulong)(load_addr + offset), len);
+		if (rc) {
+			flash_perror(rc);
+			return -1;
+		}
+	} else {
+#endif /* CONFIG_SYS_DIRECT_FLASH_WGET */
+
+		ptr = map_sysmem(load_addr + offset, len);
+		memcpy(ptr, src, len);
+		unmap_sysmem(ptr);
+
+#ifdef CONFIG_SYS_DIRECT_FLASH_WGET
+	}
+#endif
+	if (net_boot_file_size < (offset + len))
+		net_boot_file_size = newsize;
+	return 0;
+}
+
+/*
+ * 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)
+{
+	u8 action                  = r_action;
+	unsigned int tcp_ack_num   = r_tcp_ack_num;
+	unsigned int tcp_seq_num   = r_tcp_seq_num;
+	int len                    = r_len;
+	uchar *ptr;
+	uchar *offset;
+
+	tcp_ack_num = tcp_ack_num + len;
+
+	switch (wget_state) {
+	case WGET_CLOSED:
+		debug_cond(DEBUG_WGET, "wget: send SYN\n");
+		wget_state = WGET_CONNECTING;
+		net_send_tcp_packet(0, SERVER_PORT, our_port, action,
+				    tcp_seq_num, tcp_ack_num);
+		packets = 0;
+	break;
+	case WGET_CONNECTING:
+		pkt_q_idx = 0;
+		net_send_tcp_packet(0, SERVER_PORT, our_port, 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 = offset + strlen(bootfile1);
+
+		memcpy(offset, image_url, strlen(image_url));
+		offset = offset + strlen(image_url);
+
+		memcpy(offset, &bootfile3, strlen(bootfile3));
+		offset = offset + strlen(bootfile3);
+		net_send_tcp_packet((offset - ptr), SERVER_PORT, our_port,
+				    TCP_PUSH, tcp_seq_num, tcp_ack_num);
+		wget_state = WGET_CONNECTED;
+	break;
+	case WGET_CONNECTED:
+	case WGET_TRANSFERRING:
+	case WGET_TRANSFERRED:
+		net_send_tcp_packet(0, SERVER_PORT, our_port, action,
+				    tcp_seq_num, tcp_ack_num);
+	break;
+	}
+}
+
+static void wget_send(u8 action, unsigned int tcp_ack_num,
+		      unsigned int tcp_seq_num, int len)
+{
+	r_action        = action;
+	r_tcp_ack_num   = tcp_ack_num;
+	r_tcp_seq_num   = tcp_seq_num;
+	r_len           = len;
+	wget_send_stored();
+}
+
+void wget_fail(char *error_message, unsigned int tcp_seq_num,
+	       unsigned int tcp_ack_num, u8 action)
+{
+	printf("%s", error_message);
+	printf("%s", "wget: Transfer Fail\n");
+	net_set_timeout_handler(0, NULL);
+	wget_send(action, tcp_seq_num, tcp_ack_num, 0);
+}
+
+void wget_success(u8 action, unsigned int tcp_seq_num,
+		  unsigned int tcp_ack_num, int len, int packets)
+{
+	printf("Packets received %d, Transfer Successful\n", packets);
+	wget_send(action, tcp_seq_num, tcp_ack_num, len);
+}
+
+/*
+ * 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();
+	}
+}
+
+static void wget_connected(uchar *pkt, unsigned int tcp_seq_num,
+			   struct in_addr action_and_state,
+			   unsigned int tcp_ack_num, unsigned int len)
+{
+	u8 action = action_and_state.s_addr;
+	uchar *pkt_in_q;
+	char *pos;
+	int  hlen;
+	int  i;
+
+	pkt[len] = '\0';
+	pos = strstr((char *)pkt, http_eom);
+
+	if (pos == 0) {
+		debug_cond(DEBUG_WGET,
+			   "wget: Connected, data before Header %p\n", pkt);
+		pkt_in_q = (void *)load_addr + 0x20000 + (pkt_q_idx * 0x800);
+		memcpy(pkt_in_q, pkt, len);
+		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++;
+	} else {
+		debug_cond(DEBUG_WGET, "wget: Connected HTTP Header %p\n", pkt);
+		hlen = pos - (char *)pkt + sizeof(http_eom) - 1;
+		pos  = strstr((char *)pkt, linefeed);
+		if (pos > 0)
+			i = pos - (char *)pkt;
+		else
+			i = hlen;
+		tcp_print_buffer(pkt, i, i, -1, 0);
+
+		wget_state = WGET_TRANSFERRING;
+
+		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);
+			initial_data_seq_num = tcp_seq_num + hlen;
+
+			pos  = strstr((char *)pkt, content_len);
+			if (!pos) {
+				content_length = -1;
+			} else {
+				pos = 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)
+				store_block(pkt + hlen, 0, len - hlen);
+			debug_cond(DEBUG_WGET,
+				   "wget: Connected Pkt %p hlen %x\n",
+				   pkt, hlen);
+
+			for (i = 0; i < pkt_q_idx; i++) {
+				store_block(pkt_q[i].pkt,
+					    pkt_q[i].tcp_seq_num -
+						initial_data_seq_num,
+					    pkt_q[i].len);
+			debug_cond(DEBUG_WGET,
+				   "wget: Connctd pkt Q %p len %x\n",
+				   pkt_q[i].pkt, pkt_q[i].len);
+			}
+		}
+	}
+	wget_send(action, tcp_seq_num, tcp_ack_num, len);
+}
+
+	/*
+	 * In the "application push" invocation, the TCP header with all
+	 * its information is pointed to by the packet pointer.
+	 *
+	 * in the typedef
+	 *      void rxhand_tcp(uchar *pkt, unsigned int dport,
+	 *                      struct in_addr sip, unsigned int sport,
+	 *                      unsigned int len);
+	 * *pkt is the pointer to the payload
+	 * dport is used for tcp_seg_num
+	 * action_and_state.s_addr is used for TCP state
+	 * sport is used for tcp_ack_num (which is unused by the app)
+	 * pkt_ length is the payload length.
+	 */
+static void wget_handler(uchar *pkt, unsigned int tcp_seq_num,
+			 struct in_addr action_and_state,
+			 unsigned int tcp_ack_num, unsigned int len)
+{
+	enum TCP_STATE wget_tcp_state = tcp_get_tcp_state();
+	u8 action = action_and_state.s_addr;
+
+	net_set_timeout_handler(wget_timeout, wget_timeout_handler);
+	packets++;
+
+	switch (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=%x, Ack=%x\n",
+			   len, tcp_seq_num, tcp_ack_num);
+		if (len == 0) {
+			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 {
+				tcp_print_buffer(pkt, len, len, -1, 0);
+				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=%x, len=%x\n",
+			   tcp_seq_num, len);
+		if (len == 0) {
+			wget_fail("Image not found, no data returned\n",
+				  tcp_seq_num, tcp_ack_num, action);
+		} else {
+			wget_connected(pkt, tcp_seq_num, action_and_state,
+				       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 (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);
+		} else {
+			switch (wget_tcp_state) {
+			case TCP_FIN_WAIT_2:
+				wget_send(TCP_ACK, tcp_seq_num, tcp_ack_num,
+					  len);
+			case TCP_SYN_SENT:
+			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 */
+				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;
+	}
+}
+
+void wget_start(void)
+{
+	debug_cond(DEBUG_WGET, "%s\n", __func__);
+
+	image_url = strchr(net_boot_file_name, ':');
+	if (!image_url) {
+		web_server_ip = string_to_ip(net_boot_file_name);
+		++image_url;
+	} else {
+		web_server_ip = net_server_ip;
+		image_url = net_boot_file_name;
+	}
+
+	debug_cond(DEBUG_WGET,
+		   "wget: Transfer HTTP Server %pI4; our IP %pI4\n",
+		   &web_server_ip, &net_ip);
+
+	/* Check if we need to send across this subnet */
+	if (net_gateway.s_addr && net_netmask.s_addr) {
+		struct in_addr our_net;
+		struct in_addr server_net;
+
+		our_net.s_addr = net_ip.s_addr & net_netmask.s_addr;
+		server_net.s_addr = net_server_ip.s_addr & net_netmask.s_addr;
+		if (our_net.s_addr != server_net.s_addr)
+			debug_cond(DEBUG_WGET, "wget: sending through gateway %pI4",
+				   &net_gateway);
+	}
+	debug_cond(DEBUG_WGET, "URL '%s\n", image_url);
+
+	if (net_boot_file_expected_size_in_blocks) {
+		debug_cond(DEBUG_WGET, "wget: Size is 0x%x Bytes = ",
+			   net_boot_file_expected_size_in_blocks << 9);
+		print_size(net_boot_file_expected_size_in_blocks << 9, "");
+	}
+	debug_cond(DEBUG_WGET,
+		   "\nwget:Load address: 0x%lx\nLoading: *\b", load_addr);
+
+	net_set_timeout_handler(wget_timeout, wget_timeout_handler);
+	tcp_set_tcp_handler(wget_handler);
+
+	wget_timeout_count = 0;
+	wget_state = WGET_CLOSED;
+
+	our_port = random_port();
+
+	/* zero out server ether in case the server ip has changed */
+	memset(net_server_ethaddr, 0, 6);
+
+	wget_send(TCP_SYN, 0, 0, 0);
+}
-- 
2.11.0

[U-Boot] [PATCH v7 4/4] Fixed minor formatting errors.

[DH at synoia.com]

From: Duncan Hare <DuncanCHare@yahoo.com>

Too long a line in wget, line 386
Embedded blanks and tabs in clarifying comments in tcp.c

Signed-off-by: Duncan Hare <DuncanCHare@yahoo.com>
---

Changes in v7: None

 net/tcp.c  | 14 +++++++-------
 net/wget.c |  3 ++-
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/net/tcp.c b/net/tcp.c
index 612a6a4b7d..5ae2382179 100644
--- a/net/tcp.c
+++ b/net/tcp.c
@@ -23,7 +23,7 @@
 #include <environment.h>
 #include <errno.h>
 #include <net.h>
-#include <net/tcp.h>
+#include "tcp.h"
 #if defined(CONFIG_CMD_WGET)
 #include "net/wget.h"
 #endif
@@ -199,10 +199,10 @@ int net_set_ack_options(union tcp_build_pkt *b)
 	}
 
 	/*
-	* TCP lengths are stored as a rounded up number of 32 bit words
-	* Add 3 to length round up, rounded, then divided into the length
-	* in 32 bit words.
-	*/
+	 * TCP lengths are stored as a rounded up number of 32 bit words
+	 * Add 3 to length round up, rounded, then divided into the length
+	 * in 32 bit words.
+	 */
 
 	b->sack.hdr.tcp_hlen = (((TCP_HDR_SIZE + TCP_TSOPT_SIZE
 				+ tcp_lost.len + 3)  >> 2) << 4);
@@ -210,7 +210,7 @@ int net_set_ack_options(union tcp_build_pkt *b)
 	/*
 	 * This returns the actual rounded up length of the
 	 * TCP header to add to the total packet length
-	*/
+	 */
 
 	return b->sack.hdr.tcp_hlen >> 2;
 }
@@ -703,7 +703,7 @@ void rxhand_tcp_f(union tcp_build_pkt *b, unsigned int pkt_len)
 	 * its information is pointed to by the packet pointer.
 	 *
 	 * in the typedef
-	 * 	void rxhand_tcp(uchar *pkt, unsigned int dport,
+	 *      void rxhand_tcp(uchar *pkt, unsigned int dport,
 	 *                      struct in_addr sip, unsigned int sport,
 	 *                      unsigned int len);
 	 * *pkt is the pointer to the payload
diff --git a/net/wget.c b/net/wget.c
index f7923e35c8..5429a1f7b1 100644
--- a/net/wget.c
+++ b/net/wget.c
@@ -391,7 +391,8 @@ void wget_start(void)
 		our_net.s_addr = net_ip.s_addr & net_netmask.s_addr;
 		server_net.s_addr = net_server_ip.s_addr & net_netmask.s_addr;
 		if (our_net.s_addr != server_net.s_addr)
-			debug_cond(DEBUG_WGET, "wget: sending through gateway %pI4",
+			debug_cond(DEBUG_WGET,
+				   "wget: sending through gateway %pI4",
 				   &net_gateway);
 	}
 	debug_cond(DEBUG_WGET, "URL '%s\n", image_url);
-- 
2.11.0

[U-Boot] [PATCH v7 4/4] Fixed minor formatting errors.

[Joe Hershberger]

On Thu, Mar 1, 2018 at 9:00 PM,  <DH@synoia.com> wrote:
> From: Duncan Hare <DuncanCHare@yahoo.com>
>
> Too long a line in wget, line 386
> Embedded blanks and tabs in clarifying comments in tcp.c

These changes should be squashed into the previous patches.

>
> Signed-off-by: Duncan Hare <DuncanCHare@yahoo.com>