partition: check GPT partition table

Now only support GPT partition table. MBR partition table isn't
supported yet.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>

2 files changed, 307 insertions, 0 deletions

diff --git a/drivers/partition/gpt.c b/drivers/partition/gpt.c
new file mode 100644
index 00000000..9240d5a7
--- /dev/null
+++ b/drivers/partition/gpt.c
@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <assert.h>
+#include <debug.h>
+#include <errno.h>
+#include <gpt.h>
+#include <string.h>
+
+static int unicode_to_ascii(unsigned short *str_in, unsigned char *str_out)
+{
+	uint8_t *name = (uint8_t *)str_in;
+	int i;
+
+	assert((str_in != NULL) && (str_out != NULL) && (name[0] != '\0'));
+
+	/* check whether the unicode string is valid */
+	for (i = 1; i < (EFI_NAMELEN << 1); i += 2) {
+		if (name[i] != '\0')
+			return -EINVAL;
+	}
+	/* convert the unicode string to ascii string */
+	for (i = 0; i < (EFI_NAMELEN << 1); i += 2) {
+		str_out[i >> 1] = name[i];
+		if (name[i] == '\0')
+			break;
+	}
+	return 0;
+}
+
+int parse_gpt_entry(gpt_entry_t *gpt_entry, partition_entry_t *entry)
+{
+	int result;
+
+	assert((gpt_entry != 0) && (entry != 0));
+
+	if ((gpt_entry->first_lba == 0) && (gpt_entry->last_lba == 0)) {
+		return -EINVAL;
+	}
+
+	memset(entry, 0, sizeof(partition_entry_t));
+	result = unicode_to_ascii(gpt_entry->name, (uint8_t *)entry->name);
+	if (result != 0) {
+		return result;
+	}
+	entry->start = (uint64_t)gpt_entry->first_lba * PARTITION_BLOCK_SIZE;
+	entry->length = (uint64_t)(gpt_entry->last_lba -
+				   gpt_entry->first_lba + 1) *
+			PARTITION_BLOCK_SIZE;
+	return 0;
+}
diff --git a/drivers/partition/partition.c b/drivers/partition/partition.c
new file mode 100644
index 00000000..8bf6848d
--- /dev/null
+++ b/drivers/partition/partition.c
@@ -0,0 +1,229 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <assert.h>
+#include <debug.h>
+#include <io_storage.h>
+#include <gpt.h>
+#include <mbr.h>
+#include <partition.h>
+#include <platform.h>
+#include <string.h>
+
+static uint8_t mbr_sector[PARTITION_BLOCK_SIZE];
+partition_entry_list_t list;
+
+#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
+static void dump_entries(int num)
+{
+	char name[EFI_NAMELEN];
+	int i, j, len;
+
+	VERBOSE("Partition table with %d entries:\n", num);
+	for (i = 0; i < num; i++) {
+		len = snprintf(name, EFI_NAMELEN, "%s", list.list[i].name);
+		for (j = 0; j < EFI_NAMELEN - len - 1; j++) {
+			name[len + j] = ' ';
+		}
+		name[EFI_NAMELEN - 1] = '\0';
+		VERBOSE("%d: %s %lx-%lx\n", i + 1, name, list.list[i].start,
+			list.list[i].start + list.list[i].length - 4);
+	}
+}
+#else
+#define dump_entries(num)	((void)num)
+#endif
+
+/*
+ * Load the first sector that carries MBR header.
+ * The MBR boot signature should be always valid whether it's MBR or GPT.
+ */
+static int load_mbr_header(uintptr_t image_handle, mbr_entry_t *mbr_entry)
+{
+	size_t bytes_read;
+	uintptr_t offset;
+	int result;
+
+	assert(mbr_entry != NULL);
+	/* MBR partition table is in LBA0. */
+	result = io_seek(image_handle, IO_SEEK_SET, MBR_OFFSET);
+	if (result != 0) {
+		WARN("Failed to seek (%i)\n", result);
+		return result;
+	}
+	result = io_read(image_handle, (uintptr_t)&mbr_sector,
+			 PARTITION_BLOCK_SIZE, &bytes_read);
+	if (result != 0) {
+		WARN("Failed to read data (%i)\n", result);
+		return result;
+	}
+
+	/* Check MBR boot signature. */
+	if ((mbr_sector[PARTITION_BLOCK_SIZE - 2] != MBR_SIGNATURE_FIRST) ||
+	    (mbr_sector[PARTITION_BLOCK_SIZE - 1] != MBR_SIGNATURE_SECOND)) {
+		return -ENOENT;
+	}
+	offset = (uintptr_t)&mbr_sector + MBR_PRIMARY_ENTRY_OFFSET;
+	memcpy(mbr_entry, (void *)offset, sizeof(mbr_entry_t));
+	return 0;
+}
+
+/*
+ * Load GPT header and check the GPT signature.
+ * If partiton numbers could be found, check & update it.
+ */
+static int load_gpt_header(uintptr_t image_handle)
+{
+	gpt_header_t header;
+	size_t bytes_read;
+	int result;
+
+	result = io_seek(image_handle, IO_SEEK_SET, GPT_HEADER_OFFSET);
+	if (result != 0) {
+		return result;
+	}
+	result = io_read(image_handle, (uintptr_t)&header,
+			 sizeof(gpt_header_t), &bytes_read);
+	if ((result != 0) || (sizeof(gpt_header_t) != bytes_read)) {
+		return result;
+	}
+	if (memcmp(header.signature, GPT_SIGNATURE,
+		   sizeof(header.signature)) != 0) {
+		return -EINVAL;
+	}
+
+	/* partition numbers can't exceed PLAT_PARTITION_MAX_ENTRIES */
+	list.entry_count = header.list_num;
+	if (list.entry_count > PLAT_PARTITION_MAX_ENTRIES) {
+		list.entry_count = PLAT_PARTITION_MAX_ENTRIES;
+	}
+	return 0;
+}
+
+static int load_gpt_entry(uintptr_t image_handle, gpt_entry_t *entry)
+{
+	size_t bytes_read;
+	int result;
+
+	assert(entry != NULL);
+	result = io_read(image_handle, (uintptr_t)entry, sizeof(gpt_entry_t),
+			 &bytes_read);
+	if (sizeof(gpt_entry_t) != bytes_read)
+		return -EINVAL;
+	return result;
+}
+
+static int verify_partition_gpt(uintptr_t image_handle)
+{
+	gpt_entry_t entry;
+	int result, i;
+
+	for (i = 0; i < list.entry_count; i++) {
+		result = load_gpt_entry(image_handle, &entry);
+		assert(result == 0);
+		result = parse_gpt_entry(&entry, &list.list[i]);
+		if (result != 0) {
+			break;
+		}
+	}
+	if (i == 0) {
+		return -EINVAL;
+	}
+	/*
+	 * Only records the valid partition number that is loaded from
+	 * partition table.
+	 */
+	list.entry_count = i;
+	dump_entries(list.entry_count);
+
+	return 0;
+}
+
+int load_partition_table(unsigned int image_id)
+{
+	uintptr_t dev_handle, image_handle, image_spec = 0;
+	mbr_entry_t mbr_entry;
+	int result;
+
+	result = plat_get_image_source(image_id, &dev_handle, &image_spec);
+	if (result != 0) {
+		WARN("Failed to obtain reference to image id=%u (%i)\n",
+			image_id, result);
+		return result;
+	}
+
+	result = io_open(dev_handle, image_spec, &image_handle);
+	if (result != 0) {
+		WARN("Failed to access image id=%u (%i)\n", image_id, result);
+		return result;
+	}
+
+	result = load_mbr_header(image_handle, &mbr_entry);
+	if (result != 0) {
+		WARN("Failed to access image id=%u (%i)\n", image_id, result);
+		return result;
+	}
+	if (mbr_entry.type == PARTITION_TYPE_GPT) {
+		result = load_gpt_header(image_handle);
+		assert(result == 0);
+		result = io_seek(image_handle, IO_SEEK_SET, GPT_ENTRY_OFFSET);
+		assert(result == 0);
+		result = verify_partition_gpt(image_handle);
+	} else {
+		/* MBR type isn't supported yet. */
+		result = -EINVAL;
+		goto exit;
+	}
+exit:
+	io_close(image_handle);
+	return result;
+}
+
+const partition_entry_t *get_partition_entry(const char *name)
+{
+	int i;
+
+	for (i = 0; i < list.entry_count; i++) {
+		if (strcmp(name, list.list[i].name) == 0) {
+			return &list.list[i];
+		}
+	}
+	return NULL;
+}
+
+const partition_entry_list_t *get_partition_entry_list(void)
+{
+	return &list;
+}
+
+void partition_init(unsigned int image_id)
+{
+	load_partition_table(image_id);
+}