efi_loader: net: set EFI bootdevice device path to HTTP when loaded from wget

Set the device path of the efi boot device to an HTTP device path
(as formed by efi_dp_from_http) when the next boot stage is loaded
using wget (i.e., when wget is used with wget_info.set_bootdev=1).

When loaded from HTTP, the device path should account for it so that
the next boot stage is aware (e.g. grub only loads its http stack if
it itself was loaded from http, and it checks this from its device path).

Signed-off-by: Adriano Cordova <adrianox@gmail.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

include/efi_loader.h

@@ -126,6 +126,10 @@ static inline void efi_set_bootdev(const char *dev, const char *devnr,
 #endif
 
 #if CONFIG_IS_ENABLED(NETDEVICES) && CONFIG_IS_ENABLED(EFI_LOADER)
+/* Call this to update the current device path of the efi net device */
+efi_status_t efi_net_set_dp(const char *dev, const char *server);
+/* Call this to get the current device path of the efi net device */
+void efi_net_get_dp(struct efi_device_path **dp);
 void efi_net_get_addr(struct efi_ipv4_address *ip,
 		      struct efi_ipv4_address *mask,
 		      struct efi_ipv4_address *gw);
@@ -133,6 +137,7 @@ void efi_net_set_addr(struct efi_ipv4_address *ip,
 		      struct efi_ipv4_address *mask,
 		      struct efi_ipv4_address *gw);
 #else
+static inline void efi_net_get_dp(struct efi_device_path **dp) { }
 static inline void efi_net_get_addr(struct efi_ipv4_address *ip,
 				     struct efi_ipv4_address *mask,
 				     struct efi_ipv4_address *gw) { }

lib/efi_loader/efi_bootbin.c

@@ -93,24 +93,34 @@ void efi_set_bootdev(const char *dev, const char *devnr, const char *path,
 	image_addr = buffer;
 	image_size = buffer_size;
 
-	ret = efi_dp_from_name(dev, devnr, path, &device, &image);
-	if (ret == EFI_SUCCESS) {
-		bootefi_device_path = device;
-		if (image) {
-			/* FIXME: image should not contain device */
-			struct efi_device_path *image_tmp = image;
-
-			efi_dp_split_file_path(image, &device, &image);
-			efi_free_pool(image_tmp);
-		}
-		bootefi_image_path = image;
-		log_debug("- boot device %pD\n", device);
-		if (image)
-			log_debug("- image %pD\n", image);
-	} else {
-		log_debug("- efi_dp_from_name() failed, err=%lx\n", ret);
-		efi_clear_bootdev();
+#if IS_ENABLED(CONFIG_NETDEVICES)
+	if (!strcmp(dev, "Net") || !strcmp(dev, "Http")) {
+		ret = efi_net_set_dp(dev, devnr);
+		if (ret != EFI_SUCCESS)
+			goto error;
 	}
+#endif
+
+	ret = efi_dp_from_name(dev, devnr, path, &device, &image);
+	if (ret != EFI_SUCCESS)
+		goto error;
+
+	bootefi_device_path = device;
+	if (image) {
+		/* FIXME: image should not contain device */
+		struct efi_device_path *image_tmp = image;
+
+		efi_dp_split_file_path(image, &device, &image);
+		efi_free_pool(image_tmp);
+	}
+	bootefi_image_path = image;
+	log_debug("- boot device %pD\n", device);
+	if (image)
+		log_debug("- image %pD\n", image);
+	return;
+error:
+	log_debug("- efi_dp_from_name() failed, err=%lx\n", ret);
+	efi_clear_bootdev();
 }
 
 /**

lib/efi_loader/efi_device_path.c

@@ -1185,8 +1185,9 @@ efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
 
 		dp = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
 				     (uintptr_t)image_addr, image_size);
-	} else if (IS_ENABLED(CONFIG_NETDEVICES) && !strcmp(dev, "Net")) {
-		dp = efi_dp_from_eth();
+	} else if (IS_ENABLED(CONFIG_NETDEVICES) &&
+		   (!strcmp(dev, "Net") || !strcmp(dev, "Http"))) {
+		efi_net_get_dp(&dp);
 	} else if (!strcmp(dev, "Uart")) {
 		dp = efi_dp_from_uart();
 	} else {

lib/efi_loader/efi_net.c

@@ -16,6 +16,7 @@
  */
 
 #include <efi_loader.h>
+#include <dm.h>
 #include <malloc.h>
 #include <vsprintf.h>
 #include <net.h>
@@ -32,6 +33,13 @@ static int rx_packet_idx;
 static int rx_packet_num;
 static struct efi_net_obj *netobj;
 
+/*
+ * The current network device path. This device path is updated when a new
+ * bootfile is downloaded from the network. If then the bootfile is loaded
+ * as an efi image, net_dp is passed as the device path of the loaded image.
+ */
+static struct efi_device_path *net_dp;
+
 /*
  * The notification function of this event is called in every timer cycle
  * to check if a new network packet has been received.
@@ -902,8 +910,10 @@ efi_status_t efi_net_register(void)
 			     &netobj->net);
 	if (r != EFI_SUCCESS)
 		goto failure_to_add_protocol;
+	if (!net_dp)
+		efi_net_set_dp("Net", NULL);
 	r = efi_add_protocol(&netobj->header, &efi_guid_device_path,
-			     efi_dp_from_eth());
+			     net_dp);
 	if (r != EFI_SUCCESS)
 		goto failure_to_add_protocol;
 	r = efi_add_protocol(&netobj->header, &efi_pxe_base_code_protocol_guid,
@@ -999,6 +1009,49 @@ out_of_resources:
 	return EFI_OUT_OF_RESOURCES;
 }
 
+/**
+ * efi_net_set_dp() - set device path of efi net device
+ *
+ * This gets called to update the device path when a new boot
+ * file is downloaded
+ *
+ * @dev:	dev to set the device path from
+ * @server:	remote server address
+ * Return:	status code
+ */
+efi_status_t efi_net_set_dp(const char *dev, const char *server)
+{
+	efi_free_pool(net_dp);
+
+	net_dp = NULL;
+	if (!strcmp(dev, "Net"))
+		net_dp = efi_dp_from_eth();
+	else if (!strcmp(dev, "Http"))
+		net_dp = efi_dp_from_http(server);
+
+	if (!net_dp)
+		return EFI_OUT_OF_RESOURCES;
+
+	return EFI_SUCCESS;
+}
+
+/**
+ * efi_net_get_dp() - get device path of efi net device
+ *
+ * Produce a copy of the current device path
+ *
+ * @dp:		copy of the current device path, or NULL on error
+ */
+void efi_net_get_dp(struct efi_device_path **dp)
+{
+	if (!dp)
+		return;
+	if (!net_dp)
+		efi_net_set_dp("Net", NULL);
+	if (net_dp)
+		*dp = efi_dp_dup(net_dp);
+}
+
 /**
  * efi_net_get_addr() - get IP address information
  *

net/lwip/wget.c

@@ -260,10 +260,9 @@ static void httpc_result_cb(void *arg, httpc_result_t httpc_result,
 	printf("%u bytes transferred in %lu ms (", rx_content_len, elapsed);
 	print_size(rx_content_len / elapsed * 1000, "/s)\n");
 	printf("Bytes transferred = %lu (%lx hex)\n", ctx->size, ctx->size);
-	if (wget_info->set_bootdev) {
-		efi_set_bootdev("Net", "", ctx->path, map_sysmem(ctx->saved_daddr, 0),
+	if (wget_info->set_bootdev)
+		efi_set_bootdev("Http", ctx->server_name, ctx->path, map_sysmem(ctx->saved_daddr, 0),
 				rx_content_len);
-	}
 	wget_lwip_set_file_size(rx_content_len);
 	if (env_set_hex("filesize", rx_content_len) ||
 	    env_set_hex("fileaddr", ctx->saved_daddr)) {

net/wget.c

@@ -447,7 +447,7 @@ static void wget_handler(uchar *pkt, u16 dport,
 		net_set_state(wget_loop_state);
 		wget_info->file_size = net_boot_file_size;
 		if (wget_info->method == WGET_HTTP_METHOD_GET && wget_info->set_bootdev) {
-			efi_set_bootdev("Net", "", image_url,
+			efi_set_bootdev("Http", NULL, image_url,
 					map_sysmem(image_load_addr, 0),
 					net_boot_file_size);
 			env_set_hex("filesize", net_boot_file_size);