[PATCH 5/7] Add libubifs.c

[hujianyang <hujianyang@huawei.com>]

These functions are copied from fs/ubifs/scan.c and fs/ubifs/debug.c
with some small changes. We don't have 'ubifs_info *c' in user space
and we don't need to check NODEs, just print what they are.

I think if data is corrupted, kernel will warn it and we can't check
it here because the checking codes are to heavy.

case SCANNED_A_NODE:
We will get the whole detailed info about this node if we set '-i'.

I just dump detailed info with some kinds of NODEs because I think
others are useless for debugging and you can simply add what you need
if it is necessary.


Signed-off-by: hujianyang <hujianyang@huawei.com>
---
 ubi-utils/libubifs.c | 399 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 399 insertions(+)
 create mode 100644 ubi-utils/libubifs.c

diff --git a/ubi-utils/libubifs.c b/ubi-utils/libubifs.c
new file mode 100644
index 0000000..86517fa
--- /dev/null
+++ b/ubi-utils/libubifs.c
@@ -0,0 +1,399 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * Author: Hu Jianyang <hujianyang@huawei.com>
+ *
+ * UBIFS library.
+ */
+
+#define PROGRAM_NAME "libubifs"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <libubifs.h>
+#include <mtd_swab.h>
+#include "common.h"
+
+static const char *get_key_fmt(int fmt)
+{
+	switch (fmt) {
+	case UBIFS_SIMPLE_KEY_FMT:
+		return "simple";
+	default:
+		return "unknown/invalid format";
+	}
+}
+
+static const char *get_key_hash(int hash)
+{
+	switch (hash) {
+	case UBIFS_KEY_HASH_R5:
+		return "R5";
+	case UBIFS_KEY_HASH_TEST:
+		return "test";
+	default:
+		return "unknown/invalid name hash";
+	}
+}
+
+static const char *node_ntype(int type)
+{
+	switch (type) {
+	case UBIFS_PAD_NODE:
+		return "padding node";
+	case UBIFS_SB_NODE:
+		return "superblock node";
+	case UBIFS_MST_NODE:
+		return "master node";
+	case UBIFS_REF_NODE:
+		return "reference node";
+	case UBIFS_INO_NODE:
+		return "inode node";
+	case UBIFS_DENT_NODE:
+		return "direntry node";
+	case UBIFS_XENT_NODE:
+		return "xentry node";
+	case UBIFS_DATA_NODE:
+		return "data node";
+	case UBIFS_TRUN_NODE:
+		return "truncate node";
+	case UBIFS_IDX_NODE:
+		return "indexing node";
+	case UBIFS_CS_NODE:
+		return "commit start node";
+	case UBIFS_ORPH_NODE:
+		return "orphan node";
+	default:
+		return "unknown node";
+	}
+}
+
+static const char *node_gtype(int type)
+{
+	switch (type) {
+	case UBIFS_NO_NODE_GROUP:
+		return "no node group";
+	case UBIFS_IN_NODE_GROUP:
+		return "in node group";
+	case UBIFS_LAST_OF_NODE_GROUP:
+		return "last of node group";
+	default:
+		return "unknown";
+	}
+}
+
+static void dump_ch(const struct ubifs_ch *ch)
+{
+	printf("\tmagic          %#x\n", le32_to_cpu(ch->magic));
+	printf("\tcrc            %#x\n", le32_to_cpu(ch->crc));
+	printf("\tnode_type      %d (%s)\n", ch->node_type,
+	       node_ntype(ch->node_type));
+	printf("\tgroup_type     %d (%s)\n", ch->group_type,
+	       node_gtype(ch->group_type));
+	printf("\tsqnum          %llu\n",
+	       (unsigned long long)le64_to_cpu(ch->sqnum));
+	printf("\tlen            %u\n", le32_to_cpu(ch->len));
+}
+
+void ubifs_dump_node(const void *node)
+{
+	const struct ubifs_ch *ch = node;
+
+	if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) {
+		printf("Not a node, first %zu bytes:\n", UBIFS_CH_SZ);
+		return;
+	}
+
+	dump_ch(node);
+
+	switch (ch->node_type) {
+	case UBIFS_PAD_NODE:
+	{
+		const struct ubifs_pad_node *pad = node;
+
+		printf("\tpad_len        %u\n", le32_to_cpu(pad->pad_len));
+		break;
+	}
+	case UBIFS_SB_NODE:
+	{
+		const struct ubifs_sb_node *sup = node;
+		unsigned int sup_flags = le32_to_cpu(sup->flags);
+
+		printf("\tkey_hash       %d (%s)\n",
+		       (int)sup->key_hash, get_key_hash(sup->key_hash));
+		printf("\tkey_fmt        %d (%s)\n",
+		       (int)sup->key_fmt, get_key_fmt(sup->key_fmt));
+		printf("\tflags          %#x\n", sup_flags);
+		printf("\tbig_lpt      %u\n",
+		       !!(sup_flags & UBIFS_FLG_BIGLPT));
+		printf("\tspace_fixup  %u\n",
+		       !!(sup_flags & UBIFS_FLG_SPACE_FIXUP));
+		printf("\tmin_io_size    %u\n", le32_to_cpu(sup->min_io_size));
+		printf("\tleb_size       %u\n", le32_to_cpu(sup->leb_size));
+		printf("\tleb_cnt        %u\n", le32_to_cpu(sup->leb_cnt));
+		printf("\tmax_leb_cnt    %u\n", le32_to_cpu(sup->max_leb_cnt));
+		printf("\tmax_bud_bytes  %llu\n",
+		       (unsigned long long)le64_to_cpu(sup->max_bud_bytes));
+		printf("\tlog_lebs       %u\n", le32_to_cpu(sup->log_lebs));
+		printf("\tlpt_lebs       %u\n", le32_to_cpu(sup->lpt_lebs));
+		printf("\torph_lebs      %u\n", le32_to_cpu(sup->orph_lebs));
+		printf("\tjhead_cnt      %u\n", le32_to_cpu(sup->jhead_cnt));
+		printf("\tfanout         %u\n", le32_to_cpu(sup->fanout));
+		printf("\tlsave_cnt      %u\n", le32_to_cpu(sup->lsave_cnt));
+		printf("\tdefault_compr  %u\n",
+		       (int)le16_to_cpu(sup->default_compr));
+		printf("\trp_size        %llu\n",
+		       (unsigned long long)le64_to_cpu(sup->rp_size));
+		printf("\trp_uid         %u\n", le32_to_cpu(sup->rp_uid));
+		printf("\trp_gid         %u\n", le32_to_cpu(sup->rp_gid));
+		printf("\tfmt_version    %u\n", le32_to_cpu(sup->fmt_version));
+		printf("\ttime_gran      %u\n", le32_to_cpu(sup->time_gran));
+		printf("\tUUID           %pUB\n", sup->uuid);
+		break;
+	}
+	case UBIFS_MST_NODE:
+	{
+		const struct ubifs_mst_node *mst = node;
+
+		printf("\thighest_inum   %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->highest_inum));
+		printf("\tcommit number  %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->cmt_no));
+		printf("\tflags          %#x\n", le32_to_cpu(mst->flags));
+		printf("\tlog_lnum       %u\n", le32_to_cpu(mst->log_lnum));
+		printf("\troot_lnum      %u\n", le32_to_cpu(mst->root_lnum));
+		printf("\troot_offs      %u\n", le32_to_cpu(mst->root_offs));
+		printf("\troot_len       %u\n", le32_to_cpu(mst->root_len));
+		printf("\tgc_lnum        %u\n", le32_to_cpu(mst->gc_lnum));
+		printf("\tihead_lnum     %u\n", le32_to_cpu(mst->ihead_lnum));
+		printf("\tihead_offs     %u\n", le32_to_cpu(mst->ihead_offs));
+		printf("\tindex_size     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->index_size));
+		printf("\tlpt_lnum       %u\n", le32_to_cpu(mst->lpt_lnum));
+		printf("\tlpt_offs       %u\n", le32_to_cpu(mst->lpt_offs));
+		printf("\tnhead_lnum     %u\n", le32_to_cpu(mst->nhead_lnum));
+		printf("\tnhead_offs     %u\n", le32_to_cpu(mst->nhead_offs));
+		printf("\tltab_lnum      %u\n", le32_to_cpu(mst->ltab_lnum));
+		printf("\tltab_offs      %u\n", le32_to_cpu(mst->ltab_offs));
+		printf("\tlsave_lnum     %u\n", le32_to_cpu(mst->lsave_lnum));
+		printf("\tlsave_offs     %u\n", le32_to_cpu(mst->lsave_offs));
+		printf("\tlscan_lnum     %u\n", le32_to_cpu(mst->lscan_lnum));
+		printf("\tleb_cnt        %u\n", le32_to_cpu(mst->leb_cnt));
+		printf("\tempty_lebs     %u\n", le32_to_cpu(mst->empty_lebs));
+		printf("\tidx_lebs       %u\n", le32_to_cpu(mst->idx_lebs));
+		printf("\ttotal_free     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_free));
+		printf("\ttotal_dirty    %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_dirty));
+		printf("\ttotal_used     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_used));
+		printf("\ttotal_dead     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_dead));
+		printf("\ttotal_dark     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_dark));
+		break;
+	}
+	case UBIFS_REF_NODE:
+	{
+		const struct ubifs_ref_node *ref = node;
+
+		printf("\tlnum           %u\n", le32_to_cpu(ref->lnum));
+		printf("\toffs           %u\n", le32_to_cpu(ref->offs));
+		printf("\tjhead          %u\n", le32_to_cpu(ref->jhead));
+		break;
+	}
+	case UBIFS_CS_NODE:
+		break;
+	case UBIFS_INO_NODE:
+	case UBIFS_DENT_NODE:
+	case UBIFS_XENT_NODE:
+	case UBIFS_DATA_NODE:
+	case UBIFS_TRUN_NODE:
+	case UBIFS_IDX_NODE:
+	case UBIFS_ORPH_NODE:
+		printf("cannot dump node, type not support\n");
+	default:
+		printf("node type %d was not recognized\n",
+		       (int)ch->node_type);
+	}
+}
+
+/**
+ * scan_padding_bytes - scan for padding bytes.
+ * @buf: buffer to scan
+ * @len: length of buffer
+ *
+ * This function returns the number of padding bytes on success and
+ * %SCANNED_GARBAGE on failure.
+ */
+static int scan_padding_bytes(void *buf, int len)
+{
+	int pad_len = 0, max_pad_len = min_t(int, UBIFS_PAD_NODE_SZ, len);
+	uint8_t *p = buf;
+
+	printf("not a node\n");
+
+	while (pad_len < max_pad_len && *p++ == UBIFS_PADDING_BYTE)
+		pad_len += 1;
+
+	if (!pad_len || (pad_len & 7))
+		return SCANNED_GARBAGE;
+
+	printf("%d padding bytes\n", pad_len);
+
+	return pad_len;
+}
+
+/**
+ * ubifs_scan_a_node - scan for a node or padding.
+ * @buf: buffer to scan
+ * @size: logical eraseblock size
+ * @len: length of buffer
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ *
+ * This function returns a scanning code to indicate what was scanned.
+ */
+int ubifs_scan_a_node(void *buf, int leb_size, int len, int lnum, int offs)
+{
+	struct ubifs_ch *ch = buf;
+	uint32_t magic;
+
+	magic = le32_to_cpu(ch->magic);
+
+	if (magic == 0xFFFFFFFF) {
+		printf("hit empty space at LEB %d:%d\n", lnum, offs);
+		return SCANNED_EMPTY_SPACE;
+	}
+
+	if (magic != UBIFS_NODE_MAGIC)
+		return scan_padding_bytes(buf, len);
+
+	if (len < UBIFS_CH_SZ)
+		return SCANNED_GARBAGE;
+
+	printf("scanning %s at LEB %d:%d\n",
+	       node_ntype(ch->node_type), lnum, offs);
+
+	/* No ubifs_check_nodei() perform here */
+
+	if (ch->node_type == UBIFS_PAD_NODE) {
+		struct ubifs_pad_node *pad = buf;
+		int pad_len = le32_to_cpu(pad->pad_len);
+		int node_len = le32_to_cpu(ch->len);
+
+		/* Validate the padding node */
+		if (pad_len < 0 ||
+		    offs + node_len + pad_len > leb_size) {
+			printf("bad pad node at LEB %d:%d\n", lnum, offs);
+			ubifs_dump_node(pad);
+			return SCANNED_A_BAD_PAD_NODE;
+		}
+
+		/* Make the node pads to 8-byte boundary */
+		if ((node_len + pad_len) & 7) {
+			printf("bad padding length %d - %d\n",
+			       offs, offs + node_len + pad_len);
+			return SCANNED_A_BAD_PAD_NODE;
+		}
+
+		printf("%d bytes padded at LEB %d:%d, offset now %d\n", pad_len,
+			lnum, offs, ALIGN(offs + node_len + pad_len, 8));
+
+		return node_len + pad_len;
+	}
+
+	return SCANNED_A_NODE;
+}
+
+/**
+ * ubifs_scan - scan a logical eraseblock.
+ * @lnum: logical eraseblock number
+ * @sbuf: scan buffer
+ * @size: size of @buf in bytes
+ * @offs: offset to start at (usually zero)
+ * @detailed: print NODEs detailed info
+ *
+ * This function scans LEB and prints complete information about
+ * its contents.
+ */
+void  ubifs_scan(int lnum, void *sbuf, int leb_size, int offs, int detailed)
+{
+	void *buf = sbuf + offs;
+	int err, len = leb_size - offs;
+
+	printf("scan LEB %d:%d\n", lnum, offs);
+
+	while (len >= 8) {
+		struct ubifs_ch *ch = buf;
+		int node_len, ret;
+
+		printf("look at LEB %d:%d (%d bytes left)\n",
+		       lnum, offs, len);
+
+		ret = ubifs_scan_a_node(buf, leb_size, len, lnum, offs);
+		if (ret > 0) {
+			/* Padding bytes or a valid padding node */
+			offs += ret;
+			buf += ret;
+			len -= ret;
+			continue;
+		}
+
+		if (ret == SCANNED_EMPTY_SPACE)
+			/* Empty space is checked later */
+			break;
+
+		switch (ret) {
+		case SCANNED_GARBAGE:
+			printf("garbage\n");
+			goto corrupted;
+		case SCANNED_A_NODE:
+			if (detailed)
+				ubifs_dump_node(buf);
+			break;
+		case SCANNED_A_CORRUPT_NODE:
+		case SCANNED_A_BAD_PAD_NODE:
+			printf("bad node\n");
+			goto corrupted;
+		default:
+			printf("unknown\n");
+			err = -EINVAL;
+			goto error;
+		}
+
+		node_len = ALIGN(le32_to_cpu(ch->len), 8);
+		offs += node_len;
+		buf += node_len;
+		len -= node_len;
+	}
+
+	for (; len > 4; offs += 4, buf = buf + 4, len -= 4)
+		if (*(uint32_t *)buf != 0xffffffff)
+			break;
+	for (; len; offs++, buf++, len--)
+		if (*(uint8_t *)buf != 0xff) {
+			printf("corrupt empty space at LEB %d:%d\n",
+			       lnum, offs);
+			goto corrupted;
+		}
+
+	printf("stop scanning LEB %d at offset %d\n", lnum, offs);
+	return;
+
+corrupted:
+	printf("corruption at LEB %d:%d\n", lnum, offs);
+	err = -EUCLEAN;
+error:
+	printf("LEB %d scanning failed, error %d\n", lnum, err);
+}
-- 
1.8.1.4