forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
473 lines
12 KiB
473 lines
12 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* This file is part of UBIFS. |
|
* |
|
* Copyright (C) 2006-2008 Nokia Corporation. |
|
* |
|
* Authors: Artem Bityutskiy (Битюцкий Артём) |
|
* Adrian Hunter |
|
*/ |
|
|
|
/* This file implements reading and writing the master node */ |
|
|
|
#include "ubifs.h" |
|
|
|
/** |
|
* ubifs_compare_master_node - compare two UBIFS master nodes |
|
* @c: UBIFS file-system description object |
|
* @m1: the first node |
|
* @m2: the second node |
|
* |
|
* This function compares two UBIFS master nodes. Returns 0 if they are equal |
|
* and nonzero if not. |
|
*/ |
|
int ubifs_compare_master_node(struct ubifs_info *c, void *m1, void *m2) |
|
{ |
|
int ret; |
|
int behind; |
|
int hmac_offs = offsetof(struct ubifs_mst_node, hmac); |
|
|
|
/* |
|
* Do not compare the common node header since the sequence number and |
|
* hence the CRC are different. |
|
*/ |
|
ret = memcmp(m1 + UBIFS_CH_SZ, m2 + UBIFS_CH_SZ, |
|
hmac_offs - UBIFS_CH_SZ); |
|
if (ret) |
|
return ret; |
|
|
|
/* |
|
* Do not compare the embedded HMAC as well which also must be different |
|
* due to the different common node header. |
|
*/ |
|
behind = hmac_offs + UBIFS_MAX_HMAC_LEN; |
|
|
|
if (UBIFS_MST_NODE_SZ > behind) |
|
return memcmp(m1 + behind, m2 + behind, UBIFS_MST_NODE_SZ - behind); |
|
|
|
return 0; |
|
} |
|
|
|
/* mst_node_check_hash - Check hash of a master node |
|
* @c: UBIFS file-system description object |
|
* @mst: The master node |
|
* @expected: The expected hash of the master node |
|
* |
|
* This checks the hash of a master node against a given expected hash. |
|
* Note that we have two master nodes on a UBIFS image which have different |
|
* sequence numbers and consequently different CRCs. To be able to match |
|
* both master nodes we exclude the common node header containing the sequence |
|
* number and CRC from the hash. |
|
* |
|
* Returns 0 if the hashes are equal, a negative error code otherwise. |
|
*/ |
|
static int mst_node_check_hash(const struct ubifs_info *c, |
|
const struct ubifs_mst_node *mst, |
|
const u8 *expected) |
|
{ |
|
u8 calc[UBIFS_MAX_HASH_LEN]; |
|
const void *node = mst; |
|
|
|
crypto_shash_tfm_digest(c->hash_tfm, node + sizeof(struct ubifs_ch), |
|
UBIFS_MST_NODE_SZ - sizeof(struct ubifs_ch), |
|
calc); |
|
|
|
if (ubifs_check_hash(c, expected, calc)) |
|
return -EPERM; |
|
|
|
return 0; |
|
} |
|
|
|
/** |
|
* scan_for_master - search the valid master node. |
|
* @c: UBIFS file-system description object |
|
* |
|
* This function scans the master node LEBs and search for the latest master |
|
* node. Returns zero in case of success, %-EUCLEAN if there master area is |
|
* corrupted and requires recovery, and a negative error code in case of |
|
* failure. |
|
*/ |
|
static int scan_for_master(struct ubifs_info *c) |
|
{ |
|
struct ubifs_scan_leb *sleb; |
|
struct ubifs_scan_node *snod; |
|
int lnum, offs = 0, nodes_cnt, err; |
|
|
|
lnum = UBIFS_MST_LNUM; |
|
|
|
sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1); |
|
if (IS_ERR(sleb)) |
|
return PTR_ERR(sleb); |
|
nodes_cnt = sleb->nodes_cnt; |
|
if (nodes_cnt > 0) { |
|
snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, |
|
list); |
|
if (snod->type != UBIFS_MST_NODE) |
|
goto out_dump; |
|
memcpy(c->mst_node, snod->node, snod->len); |
|
offs = snod->offs; |
|
} |
|
ubifs_scan_destroy(sleb); |
|
|
|
lnum += 1; |
|
|
|
sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1); |
|
if (IS_ERR(sleb)) |
|
return PTR_ERR(sleb); |
|
if (sleb->nodes_cnt != nodes_cnt) |
|
goto out; |
|
if (!sleb->nodes_cnt) |
|
goto out; |
|
snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list); |
|
if (snod->type != UBIFS_MST_NODE) |
|
goto out_dump; |
|
if (snod->offs != offs) |
|
goto out; |
|
if (ubifs_compare_master_node(c, c->mst_node, snod->node)) |
|
goto out; |
|
|
|
c->mst_offs = offs; |
|
ubifs_scan_destroy(sleb); |
|
|
|
if (!ubifs_authenticated(c)) |
|
return 0; |
|
|
|
if (ubifs_hmac_zero(c, c->mst_node->hmac)) { |
|
err = mst_node_check_hash(c, c->mst_node, |
|
c->sup_node->hash_mst); |
|
if (err) |
|
ubifs_err(c, "Failed to verify master node hash"); |
|
} else { |
|
err = ubifs_node_verify_hmac(c, c->mst_node, |
|
sizeof(struct ubifs_mst_node), |
|
offsetof(struct ubifs_mst_node, hmac)); |
|
if (err) |
|
ubifs_err(c, "Failed to verify master node HMAC"); |
|
} |
|
|
|
if (err) |
|
return -EPERM; |
|
|
|
return 0; |
|
|
|
out: |
|
ubifs_scan_destroy(sleb); |
|
return -EUCLEAN; |
|
|
|
out_dump: |
|
ubifs_err(c, "unexpected node type %d master LEB %d:%d", |
|
snod->type, lnum, snod->offs); |
|
ubifs_scan_destroy(sleb); |
|
return -EINVAL; |
|
} |
|
|
|
/** |
|
* validate_master - validate master node. |
|
* @c: UBIFS file-system description object |
|
* |
|
* This function validates data which was read from master node. Returns zero |
|
* if the data is all right and %-EINVAL if not. |
|
*/ |
|
static int validate_master(const struct ubifs_info *c) |
|
{ |
|
long long main_sz; |
|
int err; |
|
|
|
if (c->max_sqnum >= SQNUM_WATERMARK) { |
|
err = 1; |
|
goto out; |
|
} |
|
|
|
if (c->cmt_no >= c->max_sqnum) { |
|
err = 2; |
|
goto out; |
|
} |
|
|
|
if (c->highest_inum >= INUM_WATERMARK) { |
|
err = 3; |
|
goto out; |
|
} |
|
|
|
if (c->lhead_lnum < UBIFS_LOG_LNUM || |
|
c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs || |
|
c->lhead_offs < 0 || c->lhead_offs >= c->leb_size || |
|
c->lhead_offs & (c->min_io_size - 1)) { |
|
err = 4; |
|
goto out; |
|
} |
|
|
|
if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first || |
|
c->zroot.offs >= c->leb_size || c->zroot.offs & 7) { |
|
err = 5; |
|
goto out; |
|
} |
|
|
|
if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len || |
|
c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) { |
|
err = 6; |
|
goto out; |
|
} |
|
|
|
if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) { |
|
err = 7; |
|
goto out; |
|
} |
|
|
|
if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first || |
|
c->ihead_offs % c->min_io_size || c->ihead_offs < 0 || |
|
c->ihead_offs > c->leb_size || c->ihead_offs & 7) { |
|
err = 8; |
|
goto out; |
|
} |
|
|
|
main_sz = (long long)c->main_lebs * c->leb_size; |
|
if (c->bi.old_idx_sz & 7 || c->bi.old_idx_sz >= main_sz) { |
|
err = 9; |
|
goto out; |
|
} |
|
|
|
if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last || |
|
c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) { |
|
err = 10; |
|
goto out; |
|
} |
|
|
|
if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last || |
|
c->nhead_offs < 0 || c->nhead_offs % c->min_io_size || |
|
c->nhead_offs > c->leb_size) { |
|
err = 11; |
|
goto out; |
|
} |
|
|
|
if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last || |
|
c->ltab_offs < 0 || |
|
c->ltab_offs + c->ltab_sz > c->leb_size) { |
|
err = 12; |
|
goto out; |
|
} |
|
|
|
if (c->big_lpt && (c->lsave_lnum < c->lpt_first || |
|
c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 || |
|
c->lsave_offs + c->lsave_sz > c->leb_size)) { |
|
err = 13; |
|
goto out; |
|
} |
|
|
|
if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) { |
|
err = 14; |
|
goto out; |
|
} |
|
|
|
if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) { |
|
err = 15; |
|
goto out; |
|
} |
|
|
|
if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) { |
|
err = 16; |
|
goto out; |
|
} |
|
|
|
if (c->lst.total_free < 0 || c->lst.total_free > main_sz || |
|
c->lst.total_free & 7) { |
|
err = 17; |
|
goto out; |
|
} |
|
|
|
if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) { |
|
err = 18; |
|
goto out; |
|
} |
|
|
|
if (c->lst.total_used < 0 || (c->lst.total_used & 7)) { |
|
err = 19; |
|
goto out; |
|
} |
|
|
|
if (c->lst.total_free + c->lst.total_dirty + |
|
c->lst.total_used > main_sz) { |
|
err = 20; |
|
goto out; |
|
} |
|
|
|
if (c->lst.total_dead + c->lst.total_dark + |
|
c->lst.total_used + c->bi.old_idx_sz > main_sz) { |
|
err = 21; |
|
goto out; |
|
} |
|
|
|
if (c->lst.total_dead < 0 || |
|
c->lst.total_dead > c->lst.total_free + c->lst.total_dirty || |
|
c->lst.total_dead & 7) { |
|
err = 22; |
|
goto out; |
|
} |
|
|
|
if (c->lst.total_dark < 0 || |
|
c->lst.total_dark > c->lst.total_free + c->lst.total_dirty || |
|
c->lst.total_dark & 7) { |
|
err = 23; |
|
goto out; |
|
} |
|
|
|
return 0; |
|
|
|
out: |
|
ubifs_err(c, "bad master node at offset %d error %d", c->mst_offs, err); |
|
ubifs_dump_node(c, c->mst_node, c->mst_node_alsz); |
|
return -EINVAL; |
|
} |
|
|
|
/** |
|
* ubifs_read_master - read master node. |
|
* @c: UBIFS file-system description object |
|
* |
|
* This function finds and reads the master node during file-system mount. If |
|
* the flash is empty, it creates default master node as well. Returns zero in |
|
* case of success and a negative error code in case of failure. |
|
*/ |
|
int ubifs_read_master(struct ubifs_info *c) |
|
{ |
|
int err, old_leb_cnt; |
|
|
|
c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL); |
|
if (!c->mst_node) |
|
return -ENOMEM; |
|
|
|
err = scan_for_master(c); |
|
if (err) { |
|
if (err == -EUCLEAN) |
|
err = ubifs_recover_master_node(c); |
|
if (err) |
|
/* |
|
* Note, we do not free 'c->mst_node' here because the |
|
* unmount routine will take care of this. |
|
*/ |
|
return err; |
|
} |
|
|
|
/* Make sure that the recovery flag is clear */ |
|
c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY); |
|
|
|
c->max_sqnum = le64_to_cpu(c->mst_node->ch.sqnum); |
|
c->highest_inum = le64_to_cpu(c->mst_node->highest_inum); |
|
c->cmt_no = le64_to_cpu(c->mst_node->cmt_no); |
|
c->zroot.lnum = le32_to_cpu(c->mst_node->root_lnum); |
|
c->zroot.offs = le32_to_cpu(c->mst_node->root_offs); |
|
c->zroot.len = le32_to_cpu(c->mst_node->root_len); |
|
c->lhead_lnum = le32_to_cpu(c->mst_node->log_lnum); |
|
c->gc_lnum = le32_to_cpu(c->mst_node->gc_lnum); |
|
c->ihead_lnum = le32_to_cpu(c->mst_node->ihead_lnum); |
|
c->ihead_offs = le32_to_cpu(c->mst_node->ihead_offs); |
|
c->bi.old_idx_sz = le64_to_cpu(c->mst_node->index_size); |
|
c->lpt_lnum = le32_to_cpu(c->mst_node->lpt_lnum); |
|
c->lpt_offs = le32_to_cpu(c->mst_node->lpt_offs); |
|
c->nhead_lnum = le32_to_cpu(c->mst_node->nhead_lnum); |
|
c->nhead_offs = le32_to_cpu(c->mst_node->nhead_offs); |
|
c->ltab_lnum = le32_to_cpu(c->mst_node->ltab_lnum); |
|
c->ltab_offs = le32_to_cpu(c->mst_node->ltab_offs); |
|
c->lsave_lnum = le32_to_cpu(c->mst_node->lsave_lnum); |
|
c->lsave_offs = le32_to_cpu(c->mst_node->lsave_offs); |
|
c->lscan_lnum = le32_to_cpu(c->mst_node->lscan_lnum); |
|
c->lst.empty_lebs = le32_to_cpu(c->mst_node->empty_lebs); |
|
c->lst.idx_lebs = le32_to_cpu(c->mst_node->idx_lebs); |
|
old_leb_cnt = le32_to_cpu(c->mst_node->leb_cnt); |
|
c->lst.total_free = le64_to_cpu(c->mst_node->total_free); |
|
c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty); |
|
c->lst.total_used = le64_to_cpu(c->mst_node->total_used); |
|
c->lst.total_dead = le64_to_cpu(c->mst_node->total_dead); |
|
c->lst.total_dark = le64_to_cpu(c->mst_node->total_dark); |
|
|
|
ubifs_copy_hash(c, c->mst_node->hash_root_idx, c->zroot.hash); |
|
|
|
c->calc_idx_sz = c->bi.old_idx_sz; |
|
|
|
if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS)) |
|
c->no_orphs = 1; |
|
|
|
if (old_leb_cnt != c->leb_cnt) { |
|
/* The file system has been resized */ |
|
int growth = c->leb_cnt - old_leb_cnt; |
|
|
|
if (c->leb_cnt < old_leb_cnt || |
|
c->leb_cnt < UBIFS_MIN_LEB_CNT) { |
|
ubifs_err(c, "bad leb_cnt on master node"); |
|
ubifs_dump_node(c, c->mst_node, c->mst_node_alsz); |
|
return -EINVAL; |
|
} |
|
|
|
dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs", |
|
old_leb_cnt, c->leb_cnt); |
|
c->lst.empty_lebs += growth; |
|
c->lst.total_free += growth * (long long)c->leb_size; |
|
c->lst.total_dark += growth * (long long)c->dark_wm; |
|
|
|
/* |
|
* Reflect changes back onto the master node. N.B. the master |
|
* node gets written immediately whenever mounting (or |
|
* remounting) in read-write mode, so we do not need to write it |
|
* here. |
|
*/ |
|
c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt); |
|
c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs); |
|
c->mst_node->total_free = cpu_to_le64(c->lst.total_free); |
|
c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark); |
|
} |
|
|
|
err = validate_master(c); |
|
if (err) |
|
return err; |
|
|
|
err = dbg_old_index_check_init(c, &c->zroot); |
|
|
|
return err; |
|
} |
|
|
|
/** |
|
* ubifs_write_master - write master node. |
|
* @c: UBIFS file-system description object |
|
* |
|
* This function writes the master node. Returns zero in case of success and a |
|
* negative error code in case of failure. The master node is written twice to |
|
* enable recovery. |
|
*/ |
|
int ubifs_write_master(struct ubifs_info *c) |
|
{ |
|
int err, lnum, offs, len; |
|
|
|
ubifs_assert(c, !c->ro_media && !c->ro_mount); |
|
if (c->ro_error) |
|
return -EROFS; |
|
|
|
lnum = UBIFS_MST_LNUM; |
|
offs = c->mst_offs + c->mst_node_alsz; |
|
len = UBIFS_MST_NODE_SZ; |
|
|
|
if (offs + UBIFS_MST_NODE_SZ > c->leb_size) { |
|
err = ubifs_leb_unmap(c, lnum); |
|
if (err) |
|
return err; |
|
offs = 0; |
|
} |
|
|
|
c->mst_offs = offs; |
|
c->mst_node->highest_inum = cpu_to_le64(c->highest_inum); |
|
|
|
ubifs_copy_hash(c, c->zroot.hash, c->mst_node->hash_root_idx); |
|
err = ubifs_write_node_hmac(c, c->mst_node, len, lnum, offs, |
|
offsetof(struct ubifs_mst_node, hmac)); |
|
if (err) |
|
return err; |
|
|
|
lnum += 1; |
|
|
|
if (offs == 0) { |
|
err = ubifs_leb_unmap(c, lnum); |
|
if (err) |
|
return err; |
|
} |
|
err = ubifs_write_node_hmac(c, c->mst_node, len, lnum, offs, |
|
offsetof(struct ubifs_mst_node, hmac)); |
|
|
|
return err; |
|
}
|
|
|