[U-Boot] [PATCH 4/6] cmd: add efishell command

[AKASHI Takahiro <takahiro.akashi@linaro.org>]

Currently, there is no easy way to add or modify UEFI variables.
In particular, bootmgr supports BootOrder/BootXXXX variables, it is
quite hard to define them as u-boot variables because they are represented
in a complicated and encoded format.

The new command, efishell, helps address these issues and give us
more friendly interfaces:
 * efishell boot add: add BootXXXX variable
 * efishell boot rm: remove BootXXXX variable
 * efishell boot dump: display all BootXXXX variables
 * efishell boot order: set/display a boot order (BootOrder)
 * efishell setvar: set an UEFI variable (with limited functionality)
 * efishell dumpvar: display all UEFI variables

As the name suggests, this command basically provides a subset fo UEFI
shell commands with simplified functionality.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
 cmd/Makefile   |   2 +-
 cmd/efishell.c | 531 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 532 insertions(+), 1 deletion(-)
 create mode 100644 cmd/efishell.c

diff --git a/cmd/Makefile b/cmd/Makefile
index a61fab6583df..e18fb21e4b71 100644
--- a/cmd/Makefile
+++ b/cmd/Makefile
@@ -24,7 +24,7 @@ obj-$(CONFIG_CMD_BINOP) += binop.o
 obj-$(CONFIG_CMD_BLOCK_CACHE) += blkcache.o
 obj-$(CONFIG_CMD_BMP) += bmp.o
 obj-$(CONFIG_CMD_BOOTCOUNT) += bootcount.o
-obj-$(CONFIG_CMD_BOOTEFI) += bootefi.o
+obj-$(CONFIG_CMD_BOOTEFI) += bootefi.o efishell.o
 obj-$(CONFIG_CMD_BOOTMENU) += bootmenu.o
 obj-$(CONFIG_CMD_BOOTSTAGE) += bootstage.o
 obj-$(CONFIG_CMD_BOOTZ) += bootz.o
diff --git a/cmd/efishell.c b/cmd/efishell.c
new file mode 100644
index 000000000000..7cadb9e47712
--- /dev/null
+++ b/cmd/efishell.c
@@ -0,0 +1,531 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  EFI Shell-like command
+ *
+ *  Copyright (c) 2018 Takahiro AKASHI, Linaro Limited
+ */
+
+#include <charset.h>
+#include <common.h>
+#include <command.h>
+#include <efi_loader.h>
+#include <environment.h>
+#include <errno.h>
+#include <exports.h>
+#include <search.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * From efi_variable.c,
+ *
+ * Mapping between EFI variables and u-boot variables:
+ *
+ *   efi_$guid_$varname = {attributes}(type)value
+ */
+static int do_efi_dump_var(int argc, char * const argv[])
+{
+	char regex[256];
+	char * const regexlist[] = {regex};
+	char *res = NULL;
+	int len;
+
+	if (argc > 2)
+		return CMD_RET_USAGE;
+
+	if (argc == 2)
+		snprintf(regex, 256, "efi_.*-.*-.*-.*-.*_%s", argv[1]);
+	else
+		snprintf(regex, 256, "efi_.*-.*-.*-.*-.*_.*");
+	debug("%s:%d grep uefi var %s\n", __func__, __LINE__, regex);
+
+	len = hexport_r(&env_htab, '\n', H_MATCH_REGEX | H_MATCH_KEY,
+			&res, 0, 1, regexlist);
+
+	if (len < 0)
+		return CMD_RET_FAILURE;
+
+	if (len > 0) {
+		puts(res);
+		free(res);
+		if (len < 2 && argc == 2)
+			printf("%s: not found\n", argv[1]);
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+static bool isalnum(char c)
+{
+	if (c >= '0' && c <= '9')
+		return true;
+	if (c >= 'A' && c <= 'F')
+		return true;
+	if (c >= 'a' && c <= 'f')
+		return true;
+
+	return false;
+}
+
+static int do_efi_set_var(int argc, char * const argv[])
+{
+	char *value, *data, *ptr, *ptr2 = NULL, num[3] = {'\0', '\0', '\0'};
+	unsigned long len, size;
+	u16 *var_name16;
+	efi_guid_t guid;
+	efi_status_t ret;
+
+	if (argc > 3)
+		return CMD_RET_USAGE;
+
+	if (argc == 1)
+		return CMD_RET_SUCCESS;
+
+	if (argc == 2) {
+		/* remove */
+		value = NULL;
+		size = 0;
+	} else { /* set */
+		value = argv[2];
+		if (value[0] == '=')
+			value++;
+		len = strlen(value);
+		if ((len > 2) && !strncmp(value, "0x", 2)) {
+			if ((len % 2))
+				return CMD_RET_USAGE;
+
+			data = value + 2;
+			size = (len - 2) / 2;
+			/* FIXME */
+			ptr = malloc(size);
+			ptr2 = ptr;
+			len = 0;
+			while (len < size * 2) {
+				num[0] = data[len++];
+				num[1] = data[len++];
+				if (!isalnum(num[0]) || !isalnum(num[1])) {
+					printf("Invalid format: %s\n\n", value);
+					ret = CMD_RET_USAGE;
+					goto out;
+				}
+				*ptr++ = (char)simple_strtoul(num, NULL, 16);
+			}
+			value = data;
+		} else {
+			size = len;
+		}
+	}
+
+	var_name16 = malloc((strlen(argv[1]) + 1) * 2);
+	utf8_to_utf16(var_name16, (u8 *)argv[1], strlen(argv[1]) + 1);
+
+	guid = efi_global_variable_guid;
+	ret = efi_set_variable(var_name16, &guid,
+			       EFI_VARIABLE_BOOTSERVICE_ACCESS |
+			       EFI_VARIABLE_RUNTIME_ACCESS, size, value);
+	ret = (ret == EFI_SUCCESS ? CMD_RET_SUCCESS : CMD_RET_FAILURE);
+out:
+	if (ptr2)
+		free(ptr2);
+	return ret;
+}
+
+static int do_efi_boot_add(int argc, char * const argv[])
+{
+	int id;
+	char *endp;
+	char var_name[9];
+	u16 var_name16[9];
+	efi_guid_t guid;
+	u32 attr;
+	size_t label_len, label_len16;
+	u16 *label, *p;
+	char *interface, *device, *file, *option;
+	struct efi_device_path *device_path = NULL, *file_path = NULL;
+	void *data = NULL;
+	unsigned long size;
+	int ret;
+
+	if (argc < 6 || argc > 7)
+		return CMD_RET_USAGE;
+
+	id = (int)simple_strtoul(argv[1], &endp, 0);
+	if (*endp != '\0' || id > 0xffff)
+		return CMD_RET_FAILURE;
+
+	sprintf(var_name, "Boot%04X", id);
+	utf8_to_utf16(var_name16, (u8 *)var_name, 9);
+	guid = efi_global_variable_guid;
+
+	attr = 0x1; /* always ACTIVE */
+
+	label_len = strlen(argv[2]);
+	label_len16 = utf8_utf16_strnlen(argv[2], label_len);
+	label = malloc((label_len16 + 1) * sizeof(u16));
+	if (!label)
+		return CMD_RET_FAILURE;
+	p = label;
+	utf8_utf16_strncpy(&p, argv[2], label_len);
+
+	interface = argv[3];
+	device = argv[4];
+	file = argv[5];
+	option = (argc == 6 ? "" : argv[6]);
+
+	ret = efi_dp_from_name(interface, device, file, &device_path,
+			       &file_path);
+	if (ret != EFI_SUCCESS) {
+		ret = CMD_RET_FAILURE;
+		goto out;
+	}
+
+	size = efi_marshal_load_option(attr, label, file_path, option, &data);
+	if (!size) {
+		ret = CMD_RET_FAILURE;
+		goto out;
+	}
+
+	ret = efi_set_variable(var_name16, &guid,
+			       EFI_VARIABLE_BOOTSERVICE_ACCESS |
+			       EFI_VARIABLE_RUNTIME_ACCESS, size, data);
+	ret = (ret == EFI_SUCCESS ? CMD_RET_SUCCESS : CMD_RET_FAILURE);
+out:
+	free(data);
+	free(device_path);
+	free(file_path);
+	free(label);
+	return ret;
+}
+
+static int do_efi_boot_rm(int argc, char * const argv[])
+{
+	efi_guid_t guid;
+	int id, i;
+	char *endp;
+	char var_name[9];
+	u16 var_name16[9];
+	efi_status_t ret;
+
+	if (argc == 1)
+		return CMD_RET_USAGE;
+
+	guid = efi_global_variable_guid;
+	for (i = 1; i < argc; i++, argv++) {
+		id = (int)simple_strtoul(argv[1], &endp, 0);
+		if (*endp != '\0' || id > 0xffff)
+			return CMD_RET_FAILURE;
+
+		sprintf(var_name, "Boot%04X", id);
+		utf8_to_utf16(var_name16, (u8 *)var_name, 9);
+
+		ret = efi_set_variable(var_name16, &guid,
+				       EFI_VARIABLE_BOOTSERVICE_ACCESS |
+				       EFI_VARIABLE_RUNTIME_ACCESS, 0, NULL);
+		if (ret) {
+			printf("cannot remove Boot%04X", id);
+			return CMD_RET_FAILURE;
+		}
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+static void show_efi_boot_opt_data(int id, void *data)
+{
+	struct load_option lo;
+	char *label, *p;
+	size_t label_len16, label_len;
+	u16 *dp_str;
+
+	efi_parse_load_option(&lo, data);
+
+	label_len16 = u16_strlen(lo.label);
+	label_len = utf16_utf8_strnlen(lo.label, label_len16);
+	label = malloc(label_len + 1);
+	if (!label)
+		return;
+	p = label;
+	utf16_utf8_strncpy(&p, lo.label, label_len16);
+
+	printf("Boot%04X:\n", id);
+	printf("\tattributes: %c%c%c (0x%08x)\n",
+	       /* ACTIVE */
+	       lo.attributes & 0x1 ? 'A' : '-',
+	       /* FORCE RECONNECT */
+	       lo.attributes & 0x2 ? 'R' : '-',
+	       /* HIDDEN */
+	       lo.attributes & 0x8 ? 'H' : '-',
+	       lo.attributes);
+	printf("\tlabel: %s\n", label);
+
+	dp_str = efi_dp_str(lo.file_path);
+	printf("\tfile_path: %ls\n", dp_str);
+	efi_free_pool(dp_str);
+
+	printf("\tdata: %s\n", lo.optional_data);
+
+	free(label);
+}
+
+static void show_efi_boot_opt(int id)
+{
+	char var_name[9];
+	u16 var_name16[9];
+	efi_guid_t guid;
+	void *data = NULL;
+	unsigned long size;
+	int ret;
+
+	sprintf(var_name, "Boot%04X", id);
+	utf8_to_utf16(var_name16, (u8 *)var_name, 9);
+	guid = efi_global_variable_guid;
+
+	size = 0;
+	ret = efi_get_variable(var_name16, &guid, NULL, &size, NULL);
+	if (ret == (int)EFI_BUFFER_TOO_SMALL) {
+		data = malloc(size);
+		ret = efi_get_variable(var_name16, &guid, NULL, &size, data);
+	}
+	if (ret == EFI_SUCCESS) {
+		show_efi_boot_opt_data(id, data);
+		free(data);
+	} else if (ret == EFI_NOT_FOUND) {
+		printf("Boot%04X: not found\n", id);
+	}
+}
+
+static int do_efi_boot_dump(int argc, char * const argv[])
+{
+	char regex[256];
+	char * const regexlist[] = {regex};
+	char *variables = NULL, *boot, *value;
+	int len;
+	int id;
+
+	if (argc > 1)
+		return CMD_RET_USAGE;
+
+	snprintf(regex, 256, "efi_.*-.*-.*-.*-.*_Boot[0-9A-F]+");
+
+	len = hexport_r(&env_htab, '\n', H_MATCH_REGEX | H_MATCH_KEY,
+			&variables, 0, 1, regexlist);
+
+	if (!len)
+		return CMD_RET_SUCCESS;
+
+	if (len < 0)
+		return CMD_RET_FAILURE;
+
+	boot = variables;
+	while (*boot) {
+		value = strstr(boot, "Boot") + 4;
+		id = (int)simple_strtoul(value, NULL, 16);
+		show_efi_boot_opt(id);
+		boot = strchr(boot, '\n');
+		if (!*boot)
+			break;
+		boot++;
+	}
+	free(variables);
+
+	return CMD_RET_SUCCESS;
+}
+
+static int show_efi_boot_order(void)
+{
+	efi_guid_t guid;
+	u16 *bootorder = NULL;
+	unsigned long size;
+	int num, i;
+	char var_name[9];
+	u16 var_name16[9];
+	void *data;
+	struct load_option lo;
+	char *label, *p;
+	size_t label_len16, label_len;
+	efi_status_t ret = CMD_RET_SUCCESS;
+
+	guid = efi_global_variable_guid;
+	size = 0;
+	ret = efi_get_variable(L"BootOrder", &guid, NULL, &size, NULL);
+	if (ret == EFI_BUFFER_TOO_SMALL) {
+		bootorder = malloc(size);
+		ret = efi_get_variable(L"BootOrder", &guid, NULL, &size,
+				       bootorder);
+	}
+	if (ret != EFI_SUCCESS) {
+		printf("BootOrder not defined\n");
+		return CMD_RET_SUCCESS;
+	}
+
+	num = size / sizeof(u16);
+	for (i = 0; i < num; i++) {
+		sprintf(var_name, "Boot%04X", bootorder[i]);
+		utf8_to_utf16(var_name16, (u8 *)var_name, 9);
+
+		size = 0;
+		ret = efi_get_variable(var_name16, &guid, NULL, &size, NULL);
+		if (ret != EFI_BUFFER_TOO_SMALL) {
+			printf("%2d: Boot%04X: (not defined)\n",
+			       i + 1, bootorder[i]);
+			continue;
+		}
+
+		data = malloc(size);
+		if (!data) {
+			ret = CMD_RET_FAILURE;
+			goto out;
+		}
+		ret = efi_get_variable(var_name16, &guid, NULL, &size, data);
+		if (ret != EFI_SUCCESS) {
+			free(data);
+			ret = CMD_RET_FAILURE;
+			goto out;
+		}
+
+		efi_parse_load_option(&lo, data);
+
+		label_len16 = u16_strlen(lo.label);
+		label_len = utf16_utf8_strnlen(lo.label, label_len16);
+		label = malloc(label_len + 1);
+		if (!label) {
+			free(data);
+			ret = CMD_RET_FAILURE;
+			goto out;
+		}
+		p = label;
+		utf16_utf8_strncpy(&p, lo.label, label_len16);
+		printf("%2d: Boot%04X: %s\n", i + 1, bootorder[i], label);
+		free(label);
+
+		free(data);
+	}
+out:
+	free(bootorder);
+
+	return ret;
+}
+
+static int do_efi_boot_order(int argc, char * const argv[])
+{
+	u16 *bootorder = NULL;
+	unsigned long size;
+	int id, i;
+	char *endp;
+	efi_guid_t guid;
+	efi_status_t ret;
+
+	if (argc == 1)
+		return show_efi_boot_order();
+
+	argc--;
+	argv++;
+
+	size = argc * sizeof(u16);
+	bootorder = malloc(size);
+	if (!bootorder)
+		return CMD_RET_FAILURE;
+
+	for (i = 0; i < argc; i++) {
+		id = (int)simple_strtoul(argv[i], &endp, 0);
+		if (*endp != '\0' || id > 0xffff) {
+			printf("invalid value: %s\n", argv[i]);
+			ret = CMD_RET_FAILURE;
+			goto out;
+		}
+
+		bootorder[i] = (u16)id;
+	}
+
+	guid = efi_global_variable_guid;
+	ret = efi_set_variable(L"BootOrder", &guid,
+			       EFI_VARIABLE_BOOTSERVICE_ACCESS |
+			       EFI_VARIABLE_RUNTIME_ACCESS, size, bootorder);
+	ret = (ret == EFI_SUCCESS ? CMD_RET_SUCCESS : CMD_RET_FAILURE);
+out:
+	free(bootorder);
+
+	return ret;
+}
+
+static int do_efi_boot_opt(int argc, char * const argv[])
+{
+	char *sub_command;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	argc--; argv++;
+	sub_command = argv[0];
+
+	if (!strcmp(sub_command, "add"))
+		return do_efi_boot_add(argc, argv);
+	else if (!strcmp(sub_command, "rm"))
+		return do_efi_boot_rm(argc, argv);
+	else if (!strcmp(sub_command, "dump"))
+		return do_efi_boot_dump(argc, argv);
+	else if (!strcmp(sub_command, "order"))
+		return do_efi_boot_order(argc, argv);
+	else
+		return CMD_RET_USAGE;
+}
+
+/* Interpreter command to configure EFI environment */
+static int do_efishell(cmd_tbl_t *cmdtp, int flag,
+		       int argc, char * const argv[])
+{
+	char *command;
+	/* TODO: declare this somewhere else */
+	extern efi_status_t efi_init_obj_list(void);
+	efi_status_t r;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	argc--; argv++;
+	command = argv[0];
+
+	/* Initialize EFI drivers */
+	r = efi_init_obj_list();
+	if (r != EFI_SUCCESS) {
+		printf("Error: Cannot set up EFI drivers, r = %lu\n",
+		       r & ~EFI_ERROR_MASK);
+		return CMD_RET_FAILURE;
+	}
+
+	if (!strcmp(command, "boot"))
+		return do_efi_boot_opt(argc, argv);
+	else if (!strcmp(command, "dumpvar"))
+		return do_efi_dump_var(argc, argv);
+	else if (!strcmp(command, "setvar"))
+		return do_efi_set_var(argc, argv);
+	else
+		return CMD_RET_USAGE;
+}
+
+#ifdef CONFIG_SYS_LONGHELP
+static char efishell_help_text[] =
+	"  - EFI Shell-like interface to configure EFI environment\n"
+	"\n"
+	"efishell boot add <bootid> <label> <interface> <device>[:<part>] <file path> <option>\n"
+	"  - set uefi's BOOT variable\n"
+	"efishell boot rm <bootid#1> [<bootid#2> [<bootid#3> [...]]]\n"
+	"  - set/display uefi boot order\n"
+	"efishell boot dump\n"
+	"  - display all uefi's BOOT variables\n"
+	"efishell boot order [<bootid#1> [<bootid#2> [<bootid#3> [...]]]]\n"
+	"  - set/display uefi boot order\n"
+	"\n"
+	"efishell dumpvar [<name>]\n"
+	"  - get uefi variable's value\n"
+	"efishell setvar <name> [<value>]\n"
+	"  - set/delete uefi variable's value\n"
+	"    <value> may be \"=\"...\"\", \"=0x...\" (set) or \"=\" (delete)\n";
+#endif
+
+U_BOOT_CMD(
+	efishell, 10, 0, do_efishell,
+	"Configure EFI environment",
+	efishell_help_text
+);
-- 
2.19.0