[v18,2/3] net: Add wget application

diff --git a/cmd/Kconfig b/cmd/Kconfig
index 49247a41c0..c1283d949f 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1791,6 +1791,13 @@  config SYS_DISABLE_AUTOLOAD
 	  is complete.  Enable this option to disable this behavior and instead
 	  require files to be loaded over the network by subsequent commands.
 
+config CMD_WGET
+	bool "wget"
+	select TCP
+	help
+	  wget is a simple command to download kernel, or other files,
+	  from a http server over TCP.
+
 config CMD_MII
 	bool "mii"
 	imply CMD_MDIO
diff --git a/cmd/net.c b/cmd/net.c
index 46f8c87b69..fb19d18b64 100644
--- a/cmd/net.c
+++ b/cmd/net.c
@@ -124,6 +124,19 @@  U_BOOT_CMD(
 );
 #endif
 
+#if defined(CONFIG_CMD_WGET)
+static int do_wget(struct cmd_tbl *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.h b/include/net.h
index 6d8d3fd971..5d52264360 100644
--- a/include/net.h
+++ b/include/net.h
@@ -561,7 +561,7 @@  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, FASTBOOT, WOL, UDP
+	TFTPSRV, TFTPPUT, LINKLOCAL, FASTBOOT, WOL, UDP, WGET
 };
 
 extern char	net_boot_file_name[1024];/* Boot File name */
diff --git a/include/net/wget.h b/include/net/wget.h
new file mode 100644
index 0000000000..da0920de11
--- /dev/null
+++ b/include/net/wget.h
@@ -0,0 +1,22 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Duncan Hare Copyright 2017
+ */
+
+/**
+ * wget_start() - begin wget
+ */
+void wget_start(void);
+
+enum wget_state {
+	WGET_CLOSED,
+	WGET_CONNECTING,
+	WGET_CONNECTED,
+	WGET_TRANSFERRING,
+	WGET_TRANSFERRED
+};
+
+#define DEBUG_WGET		0	/* Set to 1 for debug messages */
+#define SERVER_PORT		80
+#define WGET_RETRY_COUNT	30
+#define WGET_TIMEOUT		2000UL
diff --git a/net/Makefile b/net/Makefile
index d131d1cb1a..4f757a224c 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -31,6 +31,7 @@  obj-$(CONFIG_UDP_FUNCTION_FASTBOOT)  += fastboot.o
 obj-$(CONFIG_CMD_WOL)  += wol.o
 obj-$(CONFIG_PROT_UDP) += udp.o
 obj-$(CONFIG_PROT_TCP) += tcp.o
+obj-$(CONFIG_CMD_WGET) += wget.o
 
 # Disable this warning as it is triggered by:
 # sprintf(buf, index ? "foo%d" : "foo", index)
diff --git a/net/net.c b/net/net.c
index 5333cce57e..033ceda6e1 100644
--- a/net/net.c
+++ b/net/net.c
@@ -117,6 +117,7 @@ 
 #include "wol.h"
 #endif
 #include <net/tcp.h>
+#include <net/wget.h>
 
 /** BOOTP EXTENTIONS **/
 
@@ -505,6 +506,11 @@  restart:
 			nfs_start();
 			break;
 #endif
+#if defined(CONFIG_CMD_WGET)
+		case WGET:
+			wget_start();
+			break;
+#endif
 #if defined(CONFIG_CMD_CDP)
 		case CDP:
 			cdp_start();
diff --git a/net/wget.c b/net/wget.c
new file mode 100644
index 0000000000..ae69da49d4
--- /dev/null
+++ b/net/wget.c
@@ -0,0 +1,428 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * WGET/HTTP support driver based on U-BOOT's nfs.c
+ * Copyright Duncan Hare <dh@synoia.com> 2017
+ */
+
+#include <command.h>
+#include <common.h>
+#include <env.h>
+#include <image.h>
+#include <mapmem.h>
+#include <net.h>
+#include <net/tcp.h>
+#include <net/wget.h>
+
+static const char bootfile1[] = "GET ";
+static const char bootfile3[] = " HTTP/1.0\r\n\r\n";
+static const char http_eom[] = "\r\n\r\n";
+static const char http_ok[] = "200";
+static const char content_len[] = "Content-Length";
+static const char 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 current_wget_state;
+
+static char *image_url;
+static unsigned int wget_timeout = WGET_TIMEOUT;
+
+static enum net_loop_state wget_loop_state;
+
+/* Timeout retry parameters */
+static u8 retry_action;			/* actions for TCP retry */
+static unsigned int retry_tcp_ack_num;	/* TCP retry acknowledge number*/
+static unsigned int retry_tcp_seq_num;	/* TCP retry sequence number */
+static int retry_len;			/* TCP retry length */
+
+/**
+ * store_block() - store block in memory
+ * @src: source of data
+ * @offset: offset
+ * @len: length
+ */
+static inline int store_block(uchar *src, unsigned int offset, unsigned int len)
+{
+	ulong newsize = offset + len;
+	uchar *ptr;
+
+	ptr = map_sysmem(image_load_addr + offset, len);
+	memcpy(ptr, src, len);
+	unmap_sysmem(ptr);
+
+	if (net_boot_file_size < (offset + len))
+		net_boot_file_size = newsize;
+
+	return 0;
+}
+
+/**
+ * wget_send_stored() - wget response dispatcher
+ *
+ * WARNING, This, and only this, is the place in wget.c where
+ * SEQUENCE NUMBERS are swapped between incoming (RX)
+ * and outgoing (TX).
+ * Procedure wget_handler() is correct for RX traffic.
+ */
+static void wget_send_stored(void)
+{
+	u8 action = retry_action;
+	int len = retry_len;
+	unsigned int tcp_ack_num = retry_tcp_ack_num + len;
+	unsigned int tcp_seq_num = retry_tcp_seq_num;
+	uchar *ptr, *offset;
+
+	switch (current_wget_state) {
+	case WGET_CLOSED:
+		debug_cond(DEBUG_WGET, "wget: send SYN\n");
+		current_wget_state = WGET_CONNECTING;
+		net_send_tcp_packet(0, 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 += strlen(bootfile1);
+
+		memcpy(offset, image_url, strlen(image_url));
+		offset += strlen(image_url);
+
+		memcpy(offset, &bootfile3, strlen(bootfile3));
+		offset += strlen(bootfile3);
+		net_send_tcp_packet((offset - ptr), SERVER_PORT, our_port,
+				    TCP_PUSH, tcp_seq_num, tcp_ack_num);
+		current_wget_state = WGET_CONNECTED;
+		break;
+	case WGET_CONNECTED:
+	case WGET_TRANSFERRING:
+	case WGET_TRANSFERRED:
+		net_send_tcp_packet(0, 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)
+{
+	retry_action = action;
+	retry_tcp_ack_num = tcp_ack_num;
+	retry_tcp_seq_num = tcp_seq_num;
+	retry_len = len;
+
+	wget_send_stored();
+}
+
+void wget_fail(char *error_message, unsigned int tcp_seq_num,
+	       unsigned int tcp_ack_num, u8 action)
+{
+	printf("wget: Transfer Fail - %s\n", error_message);
+	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();
+	}
+}
+
+#define PKT_QUEUE_OFFSET 0x20000
+#define PKT_QUEUE_PACKET_SIZE 0x800
+
+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, i;
+
+	pkt[len] = '\0';
+	pos = strstr((char *)pkt, http_eom);
+
+	if (!pos) {
+		debug_cond(DEBUG_WGET,
+			   "wget: Connected, data before Header %p\n", pkt);
+		pkt_in_q = (void *)image_load_addr + PKT_QUEUE_OFFSET +
+			(pkt_q_idx * PKT_QUEUE_PACKET_SIZE);
+		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);
+		/* sizeof(http_eom) - 1 is the string length of (http_eom) */
+		hlen = pos - (char *)pkt + sizeof(http_eom) - 1;
+		pos = strstr((char *)pkt, linefeed);
+		if (pos > 0)
+			i = pos - (char *)pkt;
+		else
+			i = hlen;
+		printf("%.*s", i,  pkt);
+
+		current_wget_state = WGET_TRANSFERRING;
+
+		if (strstr((char *)pkt, http_ok) == 0) {
+			debug_cond(DEBUG_WGET,
+				   "wget: Connected Bad Xfer\n");
+			initial_data_seq_num = tcp_seq_num + hlen;
+			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 += 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);
+}
+
+/**
+ * wget_handler() - handler of wget
+ * @pkt: the pointer to the payload
+ * @tcp_seq_num: tcp sequence number
+ * @action_and_state: TCP state
+ * @tcp_ack_num: tcp acknowledge number
+ * @len: length of the payload
+ *
+ * In the "application push" invocation, the TCP header with all
+ * its information is pointed to by the packet pointer.
+ */
+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 (current_wget_state) {
+	case WGET_CLOSED:
+		debug_cond(DEBUG_WGET, "wget: Handler: Error!, State wrong\n");
+		break;
+	case WGET_CONNECTING:
+		debug_cond(DEBUG_WGET,
+			   "wget: Connecting In len=%x, Seq=%x, Ack=%x\n",
+			   len, tcp_seq_num, tcp_ack_num);
+		if (!len) {
+			if (wget_tcp_state == TCP_ESTABLISHED) {
+				debug_cond(DEBUG_WGET,
+					   "wget: Cting, send, len=%x\n", len);
+				wget_send(action, tcp_seq_num, tcp_ack_num,
+					  len);
+			} else {
+				printf("%.*s", len,  pkt);
+				wget_fail("wget: Handler Connected Fail\n",
+					  tcp_seq_num, tcp_ack_num, action);
+			}
+		}
+		break;
+	case WGET_CONNECTED:
+		debug_cond(DEBUG_WGET, "wget: Connected seq=%x, len=%x\n",
+			   tcp_seq_num, len);
+		if (!len) {
+			wget_fail("Image not found, no data returned\n",
+				  tcp_seq_num, tcp_ack_num, action);
+		} else {
+			wget_connected(pkt, tcp_seq_num, action_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);
+			return;
+		}
+
+		switch (wget_tcp_state) {
+		case TCP_FIN_WAIT_2:
+			wget_send(TCP_ACK, tcp_seq_num, tcp_ack_num, len);
+			fallthrough;
+		case TCP_SYN_SENT:
+		case TCP_CLOSING:
+		case TCP_FIN_WAIT_1:
+		case TCP_CLOSED:
+			net_set_state(NETLOOP_FAIL);
+			break;
+		case TCP_ESTABLISHED:
+			wget_send(TCP_ACK, tcp_seq_num, tcp_ack_num,
+				  len);
+			wget_loop_state = NETLOOP_SUCCESS;
+			break;
+		case TCP_CLOSE_WAIT:     /* End of transfer */
+			current_wget_state = WGET_TRANSFERRED;
+			wget_send(action | TCP_ACK | TCP_FIN,
+				  tcp_seq_num, tcp_ack_num, len);
+			break;
+		}
+		break;
+	case WGET_TRANSFERRED:
+		printf("Packets received %d, Transfer Successful\n", packets);
+		net_set_state(wget_loop_state);
+		break;
+	}
+}
+
+#define RANDOM_PORT_START 1024
+#define RANDOM_PORT_RANGE 0x4000
+
+/**
+ * random_port() - make port a little random (1024-17407)
+ *
+ * Return: random port number from 1024 to 17407
+ *
+ * This keeps the math somewhat trivial to compute, and seems to work with
+ * all supported protocols/clients/servers
+ */
+static unsigned int random_port(void)
+{
+	return RANDOM_PORT_START + (get_timer(0) % RANDOM_PORT_RANGE);
+}
+
+#define BLOCKSIZE 512
+
+void wget_start(void)
+{
+	image_url = strchr(net_boot_file_name, ':');
+	if (image_url > 0) {
+		web_server_ip = string_to_ip(net_boot_file_name);
+		++image_url;
+		net_server_ip = web_server_ip;
+	} 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 * BLOCKSIZE);
+		print_size(net_boot_file_expected_size_in_blocks * BLOCKSIZE,
+			   "");
+	}
+	debug_cond(DEBUG_WGET,
+		   "\nwget:Load address: 0x%lx\nLoading: *\b", image_load_addr);
+
+	net_set_timeout_handler(wget_timeout, wget_timeout_handler);
+	tcp_set_tcp_handler(wget_handler);
+
+	wget_timeout_count = 0;
+	current_wget_state = WGET_CLOSED;
+
+	our_port = random_port();
+
+	/*
+	 * Zero out server ether to force arp resolution in case
+	 * the server ip for the previous u-boot command, for example dns
+	 * is not the same as the web server ip.
+	 */
+
+	memset(net_server_ethaddr, 0, 6);
+
+	wget_send(TCP_SYN, 0, 0, 0);
+}