/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#include "kerncompat.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <ctype.h>
#include <uuid/uuid.h>
#include <errno.h>
#include <getopt.h>

#include "ctree.h"
#include "disk-io.h"
#include "print-tree.h"
#include "transaction.h"
#include "kernel-lib/list.h"
#include "common/utils.h"
#include "cmds/commands.h"
#include "crypto/crc32c.h"
#include "common/help.h"

static int check_csum_sblock(void *sb, int csum_size, u16 csum_type)
{
	u8 result[BTRFS_CSUM_SIZE];

	btrfs_csum_data(NULL, csum_type, (u8 *)sb + BTRFS_CSUM_SIZE,
			result, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);

	return !memcmp(sb, result, csum_size);
}

static void print_sys_chunk_array(struct btrfs_super_block *sb)
{
	struct extent_buffer *buf;
	struct btrfs_disk_key *disk_key;
	struct btrfs_chunk *chunk;
	u8 *array_ptr;
	unsigned long sb_array_offset;
	u32 num_stripes;
	u32 array_size;
	u32 len = 0;
	u32 cur_offset;
	struct btrfs_key key;
	int item;

	buf = malloc(sizeof(*buf) + sizeof(*sb));
	if (!buf) {
		error("not enough memory");
		return;
	}
	write_extent_buffer(buf, sb, 0, sizeof(*sb));
	buf->len = sizeof(*sb);
	array_size = btrfs_super_sys_array_size(sb);

	array_ptr = sb->sys_chunk_array;
	sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);

	if (array_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
		error("sys_array_size %u shouldn't exceed %u bytes",
				array_size, BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
		goto out;
	}

	cur_offset = 0;
	item = 0;

	while (cur_offset < array_size) {
		disk_key = (struct btrfs_disk_key *)array_ptr;
		len = sizeof(*disk_key);
		if (cur_offset + len > array_size)
			goto out_short_read;

		btrfs_disk_key_to_cpu(&key, disk_key);

		array_ptr += len;
		sb_array_offset += len;
		cur_offset += len;

		printf("\titem %d ", item);
		btrfs_print_key(disk_key);
		putchar('\n');

		if (key.type == BTRFS_CHUNK_ITEM_KEY) {
			chunk = (struct btrfs_chunk *)sb_array_offset;
			/*
			 * At least one btrfs_chunk with one stripe must be
			 * present, exact stripe count check comes afterwards
			 */
			len = btrfs_chunk_item_size(1);
			if (cur_offset + len > array_size)
				goto out_short_read;

			num_stripes = btrfs_chunk_num_stripes(buf, chunk);
			if (!num_stripes) {
				error(
			"invalid number of stripes %u in sys_array at offset %u",
					num_stripes, cur_offset);
				break;
			}
			len = btrfs_chunk_item_size(num_stripes);
			if (cur_offset + len > array_size)
				goto out_short_read;
			print_chunk_item(buf, chunk);
		} else {
			error("unexpected item type %u in sys_array at offset %u",
				(u32)key.type, cur_offset);
			break;
		}
		array_ptr += len;
		sb_array_offset += len;
		cur_offset += len;

		item++;
	}

out:
	free(buf);
	return;

out_short_read:
	error("sys_array too short to read %u bytes at offset %u",
			len, cur_offset);
	free(buf);
}

static int empty_backup(struct btrfs_root_backup *backup)
{
	if (backup == NULL ||
		(backup->tree_root == 0 &&
		 backup->tree_root_gen == 0))
		return 1;
	return 0;
}

static void print_root_backup(struct btrfs_root_backup *backup)
{
	printf("\t\tbackup_tree_root:\t%llu\tgen: %llu\tlevel: %d\n",
			btrfs_backup_tree_root(backup),
			btrfs_backup_tree_root_gen(backup),
			btrfs_backup_tree_root_level(backup));
	printf("\t\tbackup_chunk_root:\t%llu\tgen: %llu\tlevel: %d\n",
			btrfs_backup_chunk_root(backup),
			btrfs_backup_chunk_root_gen(backup),
			btrfs_backup_chunk_root_level(backup));
	printf("\t\tbackup_extent_root:\t%llu\tgen: %llu\tlevel: %d\n",
			btrfs_backup_extent_root(backup),
			btrfs_backup_extent_root_gen(backup),
			btrfs_backup_extent_root_level(backup));
	printf("\t\tbackup_fs_root:\t\t%llu\tgen: %llu\tlevel: %d\n",
			btrfs_backup_fs_root(backup),
			btrfs_backup_fs_root_gen(backup),
			btrfs_backup_fs_root_level(backup));
	printf("\t\tbackup_dev_root:\t%llu\tgen: %llu\tlevel: %d\n",
			btrfs_backup_dev_root(backup),
			btrfs_backup_dev_root_gen(backup),
			btrfs_backup_dev_root_level(backup));
	printf("\t\tbackup_csum_root:\t%llu\tgen: %llu\tlevel: %d\n",
			btrfs_backup_csum_root(backup),
			btrfs_backup_csum_root_gen(backup),
			btrfs_backup_csum_root_level(backup));

	printf("\t\tbackup_total_bytes:\t%llu\n",
					btrfs_backup_total_bytes(backup));
	printf("\t\tbackup_bytes_used:\t%llu\n",
					btrfs_backup_bytes_used(backup));
	printf("\t\tbackup_num_devices:\t%llu\n",
					btrfs_backup_num_devices(backup));
	putchar('\n');
}

static void print_backup_roots(struct btrfs_super_block *sb)
{
	struct btrfs_root_backup *backup;
	int i;

	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
		backup = sb->super_roots + i;
		if (!empty_backup(backup)) {
			printf("\tbackup %d:\n", i);
			print_root_backup(backup);
		}
	}
}

struct readable_flag_entry {
	u64 bit;
	char *output;
};

#define DEF_COMPAT_RO_FLAG_ENTRY(bit_name)		\
	{BTRFS_FEATURE_COMPAT_RO_##bit_name, #bit_name}

static struct readable_flag_entry compat_ro_flags_array[] = {
	DEF_COMPAT_RO_FLAG_ENTRY(FREE_SPACE_TREE),
	DEF_COMPAT_RO_FLAG_ENTRY(FREE_SPACE_TREE_VALID),
};
static const int compat_ro_flags_num = sizeof(compat_ro_flags_array) /
				       sizeof(struct readable_flag_entry);

#define DEF_INCOMPAT_FLAG_ENTRY(bit_name)		\
	{BTRFS_FEATURE_INCOMPAT_##bit_name, #bit_name}

static struct readable_flag_entry incompat_flags_array[] = {
	DEF_INCOMPAT_FLAG_ENTRY(MIXED_BACKREF),
	DEF_INCOMPAT_FLAG_ENTRY(DEFAULT_SUBVOL),
	DEF_INCOMPAT_FLAG_ENTRY(MIXED_GROUPS),
	DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_LZO),
	DEF_INCOMPAT_FLAG_ENTRY(COMPRESS_ZSTD),
	DEF_INCOMPAT_FLAG_ENTRY(BIG_METADATA),
	DEF_INCOMPAT_FLAG_ENTRY(EXTENDED_IREF),
	DEF_INCOMPAT_FLAG_ENTRY(RAID56),
	DEF_INCOMPAT_FLAG_ENTRY(SKINNY_METADATA),
	DEF_INCOMPAT_FLAG_ENTRY(NO_HOLES),
	DEF_INCOMPAT_FLAG_ENTRY(METADATA_UUID),
	DEF_INCOMPAT_FLAG_ENTRY(RAID1C34),
};
static const int incompat_flags_num = sizeof(incompat_flags_array) /
				      sizeof(struct readable_flag_entry);

#define DEF_HEADER_FLAG_ENTRY(bit_name)			\
	{BTRFS_HEADER_FLAG_##bit_name, #bit_name}
#define DEF_SUPER_FLAG_ENTRY(bit_name)			\
	{BTRFS_SUPER_FLAG_##bit_name, #bit_name}

static struct readable_flag_entry super_flags_array[] = {
	DEF_HEADER_FLAG_ENTRY(WRITTEN),
	DEF_HEADER_FLAG_ENTRY(RELOC),
	DEF_SUPER_FLAG_ENTRY(CHANGING_FSID),
	DEF_SUPER_FLAG_ENTRY(SEEDING),
	DEF_SUPER_FLAG_ENTRY(METADUMP),
	DEF_SUPER_FLAG_ENTRY(METADUMP_V2)
};
static const int super_flags_num = ARRAY_SIZE(super_flags_array);

#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
				 BTRFS_HEADER_FLAG_RELOC |\
				 BTRFS_SUPER_FLAG_CHANGING_FSID |\
				 BTRFS_SUPER_FLAG_SEEDING |\
				 BTRFS_SUPER_FLAG_METADUMP |\
				 BTRFS_SUPER_FLAG_METADUMP_V2)

static void __print_readable_flag(u64 flag, struct readable_flag_entry *array,
				  int array_size, u64 supported_flags)
{
	int i;
	int first = 1;
	struct readable_flag_entry *entry;

	if (!flag)
		return;

	printf("\t\t\t( ");
	for (i = 0; i < array_size; i++) {
		entry = array + i;
		if (flag & entry->bit) {
			if (first)
				printf("%s ", entry->output);
			else
				printf("|\n\t\t\t  %s ", entry->output);
			first = 0;
		}
	}
	flag &= ~supported_flags;
	if (flag) {
		if (first)
			printf("unknown flag: 0x%llx ", flag);
		else
			printf("|\n\t\t\t  unknown flag: 0x%llx ", flag);
	}
	printf(")\n");
}

static void print_readable_compat_ro_flag(u64 flag)
{
	/*
	 * We know about the FREE_SPACE_TREE{,_VALID} bits, but we don't
	 * actually support them yet.
	 */
	return __print_readable_flag(flag, compat_ro_flags_array,
				     compat_ro_flags_num,
				     BTRFS_FEATURE_COMPAT_RO_SUPP |
				     BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE |
				     BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID);
}

static void print_readable_incompat_flag(u64 flag)
{
	return __print_readable_flag(flag, incompat_flags_array,
				     incompat_flags_num,
				     BTRFS_FEATURE_INCOMPAT_SUPP);
}

static void print_readable_super_flag(u64 flag)
{
	return __print_readable_flag(flag, super_flags_array,
				     super_flags_num, BTRFS_SUPER_FLAG_SUPP);
}

static bool is_valid_csum_type(u16 csum_type)
{
	switch (csum_type) {
	case BTRFS_CSUM_TYPE_CRC32:
	case BTRFS_CSUM_TYPE_XXHASH:
	case BTRFS_CSUM_TYPE_SHA256:
	case BTRFS_CSUM_TYPE_BLAKE2:
	case BTRFS_CSUM_TYPE_HMAC_SHA256:
		return true;
	default:
		return false;
	}
}

static void dump_superblock(struct btrfs_super_block *sb, int full)
{
	int i;
	char *s, buf[BTRFS_UUID_UNPARSED_SIZE];
	u8 *p;
	u32 csum_size;
	u16 csum_type;
	bool metadata_uuid_present = (btrfs_super_incompat_flags(sb) &
		BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
	int cmp_res = 0;


	csum_type = btrfs_super_csum_type(sb);
	csum_size = BTRFS_CSUM_SIZE;
	printf("csum_type\t\t%hu (", csum_type);
	if (!is_valid_csum_type(csum_type)) {
		printf("INVALID");
	} else {
		printf("%s", btrfs_super_csum_name(csum_type));
		csum_size = btrfs_super_csum_size(sb);
	}
	printf(")\n");
	printf("csum_size\t\t%llu\n", (unsigned long long)csum_size);

	printf("csum\t\t\t0x");
	for (i = 0, p = sb->csum; i < csum_size; i++)
		printf("%02x", p[i]);
	if (csum_type == BTRFS_CSUM_TYPE_HMAC_SHA256)
		printf(" [NO KEY FOR HMAC]");
	else if (!is_valid_csum_type(csum_type))
		printf(" [UNKNOWN CSUM TYPE OR SIZE]");
	else if (check_csum_sblock(sb, csum_size, csum_type))
		printf(" [match]");
	else
		printf(" [DON'T MATCH]");
	putchar('\n');

	printf("bytenr\t\t\t%llu\n",
		(unsigned long long)btrfs_super_bytenr(sb));
	printf("flags\t\t\t0x%llx\n",
		(unsigned long long)btrfs_super_flags(sb));
	print_readable_super_flag(btrfs_super_flags(sb));

	printf("magic\t\t\t");
	s = (char *) &sb->magic;
	for (i = 0; i < 8; i++)
		putchar(isprint(s[i]) ? s[i] : '.');
	if (btrfs_super_magic(sb) == BTRFS_MAGIC)
		printf(" [match]\n");
	else
		printf(" [DON'T MATCH]\n");

	uuid_unparse(sb->fsid, buf);
	printf("fsid\t\t\t%s\n", buf);
	if (metadata_uuid_present) {
		uuid_unparse(sb->metadata_uuid, buf);
		printf("metadata_uuid\t\t%s\n", buf);
	} else {
		printf("metadata_uuid\t\t%s\n", buf);
	}

	printf("label\t\t\t");
	s = sb->label;
	for (i = 0; i < BTRFS_LABEL_SIZE && s[i]; i++)
		putchar(isprint(s[i]) ? s[i] : '.');
	putchar('\n');

	printf("generation\t\t%llu\n",
	       (unsigned long long)btrfs_super_generation(sb));
	printf("root\t\t\t%llu\n", (unsigned long long)btrfs_super_root(sb));
	printf("sys_array_size\t\t%llu\n",
	       (unsigned long long)btrfs_super_sys_array_size(sb));
	printf("chunk_root_generation\t%llu\n",
	       (unsigned long long)btrfs_super_chunk_root_generation(sb));
	printf("root_level\t\t%llu\n",
	       (unsigned long long)btrfs_super_root_level(sb));
	printf("chunk_root\t\t%llu\n",
	       (unsigned long long)btrfs_super_chunk_root(sb));
	printf("chunk_root_level\t%llu\n",
	       (unsigned long long)btrfs_super_chunk_root_level(sb));
	printf("log_root\t\t%llu\n",
	       (unsigned long long)btrfs_super_log_root(sb));
	printf("log_root_transid\t%llu\n",
	       (unsigned long long)btrfs_super_log_root_transid(sb));
	printf("log_root_level\t\t%llu\n",
	       (unsigned long long)btrfs_super_log_root_level(sb));
	printf("total_bytes\t\t%llu\n",
	       (unsigned long long)btrfs_super_total_bytes(sb));
	printf("bytes_used\t\t%llu\n",
	       (unsigned long long)btrfs_super_bytes_used(sb));
	printf("sectorsize\t\t%llu\n",
	       (unsigned long long)btrfs_super_sectorsize(sb));
	printf("nodesize\t\t%llu\n",
	       (unsigned long long)btrfs_super_nodesize(sb));
	printf("leafsize (deprecated)\t%u\n",
	       le32_to_cpu(sb->__unused_leafsize));
	printf("stripesize\t\t%llu\n",
	       (unsigned long long)btrfs_super_stripesize(sb));
	printf("root_dir\t\t%llu\n",
	       (unsigned long long)btrfs_super_root_dir(sb));
	printf("num_devices\t\t%llu\n",
	       (unsigned long long)btrfs_super_num_devices(sb));
	printf("compat_flags\t\t0x%llx\n",
	       (unsigned long long)btrfs_super_compat_flags(sb));
	printf("compat_ro_flags\t\t0x%llx\n",
	       (unsigned long long)btrfs_super_compat_ro_flags(sb));
	print_readable_compat_ro_flag(btrfs_super_compat_ro_flags(sb));
	printf("incompat_flags\t\t0x%llx\n",
	       (unsigned long long)btrfs_super_incompat_flags(sb));
	print_readable_incompat_flag(btrfs_super_incompat_flags(sb));
	printf("cache_generation\t%llu\n",
	       (unsigned long long)btrfs_super_cache_generation(sb));
	printf("uuid_tree_generation\t%llu\n",
	       (unsigned long long)btrfs_super_uuid_tree_generation(sb));

	uuid_unparse(sb->dev_item.uuid, buf);
	printf("dev_item.uuid\t\t%s\n", buf);

	uuid_unparse(sb->dev_item.fsid, buf);
	if (metadata_uuid_present) {
		cmp_res = !memcmp(sb->dev_item.fsid, sb->metadata_uuid,
				 BTRFS_FSID_SIZE);
	} else {
		cmp_res = !memcmp(sb->dev_item.fsid, sb->fsid, BTRFS_FSID_SIZE);
	}
	printf("dev_item.fsid\t\t%s %s\n", buf,
	       cmp_res ? "[match]" : "[DON'T MATCH]");

	printf("dev_item.type\t\t%llu\n", (unsigned long long)
	       btrfs_stack_device_type(&sb->dev_item));
	printf("dev_item.total_bytes\t%llu\n", (unsigned long long)
	       btrfs_stack_device_total_bytes(&sb->dev_item));
	printf("dev_item.bytes_used\t%llu\n", (unsigned long long)
	       btrfs_stack_device_bytes_used(&sb->dev_item));
	printf("dev_item.io_align\t%u\n", (unsigned int)
	       btrfs_stack_device_io_align(&sb->dev_item));
	printf("dev_item.io_width\t%u\n", (unsigned int)
	       btrfs_stack_device_io_width(&sb->dev_item));
	printf("dev_item.sector_size\t%u\n", (unsigned int)
	       btrfs_stack_device_sector_size(&sb->dev_item));
	printf("dev_item.devid\t\t%llu\n",
	       btrfs_stack_device_id(&sb->dev_item));
	printf("dev_item.dev_group\t%u\n", (unsigned int)
	       btrfs_stack_device_group(&sb->dev_item));
	printf("dev_item.seek_speed\t%u\n", (unsigned int)
	       btrfs_stack_device_seek_speed(&sb->dev_item));
	printf("dev_item.bandwidth\t%u\n", (unsigned int)
	       btrfs_stack_device_bandwidth(&sb->dev_item));
	printf("dev_item.generation\t%llu\n", (unsigned long long)
	       btrfs_stack_device_generation(&sb->dev_item));
	if (full) {
		printf("sys_chunk_array[%d]:\n", BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
		print_sys_chunk_array(sb);
		printf("backup_roots[%d]:\n", BTRFS_NUM_BACKUP_ROOTS);
		print_backup_roots(sb);
	}
}

static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr, int full,
		int force)
{
	u8 super_block_data[BTRFS_SUPER_INFO_SIZE];
	struct btrfs_super_block *sb;
	u64 ret;

	sb = (struct btrfs_super_block *)super_block_data;

	ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
	if (ret != BTRFS_SUPER_INFO_SIZE) {
		/* check if the disk if too short for further superblock */
		if (ret == 0 && errno == 0)
			return 0;

		error("failed to read the superblock on %s at %llu",
				filename, (unsigned long long)sb_bytenr);
		error("error = '%m', errno = %d", errno);
		return 1;
	}
	printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename);
	printf("---------------------------------------------------------\n");
	if (btrfs_super_magic(sb) != BTRFS_MAGIC && !force) {
		error("bad magic on superblock on %s at %llu",
				filename, (unsigned long long)sb_bytenr);
	} else {
		dump_superblock(sb, full);
	}
	return 0;
}

static const char * const cmd_inspect_dump_super_usage[] = {
	"btrfs inspect-internal dump-super [options] device [device...]",
	"Dump superblock from a device in a textual form",
	"",
	"-f|--full             print full superblock information, backup roots etc.",
	"-a|--all              print information about all superblocks",
	"-s|--super <super>    specify which copy to print out (values: 0, 1, 2)",
	"-F|--force            attempt to dump superblocks with bad magic",
	"--bytenr <offset>     specify alternate superblock offset",
	"",
	"Deprecated syntax:",
	"-s <bytenr>           specify alternate superblock offset, values other than 0, 1, 2",
	"                      will be interpreted as --bytenr for backward compatibility,",
	"                      option renamed for consistency with other tools (eg. check)",
	"-i <super>            specify which copy to print out (values: 0, 1, 2), now moved",
	"                      to -s|--super",
	NULL
};

static int cmd_inspect_dump_super(const struct cmd_struct *cmd,
				  int argc, char **argv)
{
	int all = 0;
	int full = 0;
	int force = 0;
	char *filename;
	int fd = -1;
	int i;
	int ret = 0;
	u64 arg;
	u64 sb_bytenr = btrfs_sb_offset(0);

	while (1) {
		int c;
		enum { GETOPT_VAL_BYTENR = 257 };
		static const struct option long_options[] = {
			{"all", no_argument, NULL, 'a'},
			{"bytenr", required_argument, NULL, GETOPT_VAL_BYTENR },
			{"full", no_argument, NULL, 'f'},
			{"force", no_argument, NULL, 'F'},
			{"super", required_argument, NULL, 's' },
			{NULL, 0, NULL, 0}
		};

		c = getopt_long(argc, argv, "fFai:s:", long_options, NULL);
		if (c < 0)
			break;

		switch (c) {
		case 'i':
			warning(
			    "option -i is deprecated, please use -s or --super");
			arg = arg_strtou64(optarg);
			if (arg >= BTRFS_SUPER_MIRROR_MAX) {
				error("super mirror too big: %llu >= %d",
					arg, BTRFS_SUPER_MIRROR_MAX);
				return 1;
			}
			sb_bytenr = btrfs_sb_offset(arg);
			break;

		case 'a':
			all = 1;
			break;
		case 'f':
			full = 1;
			break;
		case 'F':
			force = 1;
			break;
		case 's':
			arg = arg_strtou64(optarg);
			if (BTRFS_SUPER_MIRROR_MAX <= arg) {
				warning(
		"deprecated use of -s <bytenr> with %llu, assuming --bytenr",
						(unsigned long long)arg);
				sb_bytenr = arg;
			} else {
				sb_bytenr = btrfs_sb_offset(arg);
			}
			all = 0;
			break;
		case GETOPT_VAL_BYTENR:
			arg = arg_strtou64(optarg);
			sb_bytenr = arg;
			all = 0;
			break;
		default:
			usage_unknown_option(cmd, argv);
		}
	}

	if (check_argc_min(argc - optind, 1))
		return 1;

	for (i = optind; i < argc; i++) {
		filename = argv[i];
		fd = open(filename, O_RDONLY);
		if (fd < 0) {
			error("cannot open %s: %m", filename);
			ret = 1;
			goto out;
		}

		if (all) {
			int idx;

			for (idx = 0; idx < BTRFS_SUPER_MIRROR_MAX; idx++) {
				sb_bytenr = btrfs_sb_offset(idx);
				if (load_and_dump_sb(filename, fd,
						sb_bytenr, full, force)) {
					close(fd);
					ret = 1;
					goto out;
				}

				putchar('\n');
			}
		} else {
			load_and_dump_sb(filename, fd, sb_bytenr, full, force);
			putchar('\n');
		}
		close(fd);
	}

out:
	return ret;
}
DEFINE_SIMPLE_COMMAND(inspect_dump_super, "dump-super");