[PATCH] UBIFS: add crypto lookup field to tree node cache
Joel Reardon
joel at clambassador.com
Fri May 11 07:24:34 EDT 2012
This patch adds a new field to the TNC's zbranch and allows it to be set when
a node is added or replaced. The field is called 'crypto_lookup' and it refers
to a location in the key storage area---a pointer to a key that is used to
encrypt/decrypt the data node. It can be set to 0 or a negative number when it
is not being used. When a new node is added, this value is passed and set
When a node is replace, the old value is replaced with the new value.
These values will be used in future patchs. Replacing a
crypto_lookup value will also mark the old value as deleted and the new value
as used; adding a new node will mark the value as used. Additionally, deleting
or removing TNC nodes will mark the values as deleted.
TNC's crypto_lookup values are not stored on disk. They will be stored in the
data
node's header. Therefore, if a crypto_lookup value is invalid (but a valid one
is to be expected and needs to be used) then a function will be added that
reads the data node to
obtain the value. Additionally, when a data node is ever read, the
crypto_lookup position that is read will be set in the corresponding zbranch.
The values are not stored on disk to avoid having different on-disk formats of
the the ubifs_branch structure.
Signed-off-by: Joel Reardon <reardonj at inf.ethz.ch>
---
fs/ubifs/gc.c | 2 +-
fs/ubifs/journal.c | 24 ++++++++++++------------
fs/ubifs/replay.c | 2 +-
fs/ubifs/tnc.c | 11 +++++++++--
fs/ubifs/tnc_misc.c | 1 +
fs/ubifs/ubifs.h | 7 +++++--
6 files changed, 29 insertions(+), 18 deletions(-)
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index ded29f6..528ed58 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -330,7 +330,7 @@ static int move_node(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
err = ubifs_tnc_replace(c, &snod->key, sleb->lnum,
snod->offs, new_lnum, new_offs,
- snod->len);
+ snod->len, 0);
list_del(&snod->list);
kfree(snod);
return err;
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
index 57c4d2f..f3eb13c 100644
--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -646,13 +646,13 @@ int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
*/
ino_key_init(c, &ino_key, inode->i_ino);
ino_offs = dent_offs + aligned_dlen;
- err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
+ err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen, 0);
if (err)
goto out_ro;
ino_key_init(c, &ino_key, dir->i_ino);
ino_offs += aligned_ilen;
- err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ);
+ err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ, 0);
if (err)
goto out_ro;
@@ -747,7 +747,7 @@ int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
release_head(c, DATAHD);
- err = ubifs_tnc_add(c, key, lnum, offs, dlen);
+ err = ubifs_tnc_add(c, key, lnum, offs, dlen, 0);
if (err)
goto out_ro;
@@ -825,7 +825,7 @@ int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode)
union ubifs_key key;
ino_key_init(c, &key, inode->i_ino);
- err = ubifs_tnc_add(c, &key, lnum, offs, len);
+ err = ubifs_tnc_add(c, &key, lnum, offs, len, 0);
}
if (err)
goto out_ro;
@@ -1048,21 +1048,21 @@ int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
offs += aligned_dlen1 + aligned_dlen2;
if (new_inode) {
ino_key_init(c, &key, new_inode->i_ino);
- err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
+ err = ubifs_tnc_add(c, &key, lnum, offs, ilen, 0);
if (err)
goto out_ro;
offs += ALIGN(ilen, 8);
}
ino_key_init(c, &key, old_dir->i_ino);
- err = ubifs_tnc_add(c, &key, lnum, offs, plen);
+ err = ubifs_tnc_add(c, &key, lnum, offs, plen, 0);
if (err)
goto out_ro;
if (old_dir != new_dir) {
offs += ALIGN(plen, 8);
ino_key_init(c, &key, new_dir->i_ino);
- err = ubifs_tnc_add(c, &key, lnum, offs, plen);
+ err = ubifs_tnc_add(c, &key, lnum, offs, plen, 0);
if (err)
goto out_ro;
}
@@ -1226,13 +1226,13 @@ int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
if (dlen) {
sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
- err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
+ err = ubifs_tnc_add(c, &key, lnum, sz, dlen, 0);
if (err)
goto out_ro;
}
ino_key_init(c, &key, inum);
- err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
+ err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ, 0);
if (err)
goto out_ro;
@@ -1367,7 +1367,7 @@ int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
/* And update TNC with the new host inode position */
ino_key_init(c, &key1, host->i_ino);
- err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
+ err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen, 0);
if (err)
goto out_ro;
@@ -1440,12 +1440,12 @@ int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
goto out_ro;
ino_key_init(c, &key, host->i_ino);
- err = ubifs_tnc_add(c, &key, lnum, offs, len1);
+ err = ubifs_tnc_add(c, &key, lnum, offs, len1, 0);
if (err)
goto out_ro;
ino_key_init(c, &key, inode->i_ino);
- err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
+ err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2, 0);
if (err)
goto out_ro;
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
index b007637..f029b2d 100644
--- a/fs/ubifs/replay.c
+++ b/fs/ubifs/replay.c
@@ -252,7 +252,7 @@ static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
}
else
err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs,
- r->len);
+ r->len, 0);
if (err)
return err;
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
index 16ad84d..b222a72 100644
--- a/fs/ubifs/tnc.c
+++ b/fs/ubifs/tnc.c
@@ -2158,13 +2158,14 @@ do_split:
* @lnum: LEB number of node
* @offs: node offset
* @len: node length
+ * @crypto_lookup: the node's cryptographic key's position in the KSA
*
* This function adds a node with key @key to TNC. The node may be new or it may
* obsolete some existing one. Returns %0 on success or negative error code on
* failure.
*/
int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
- int offs, int len)
+ int offs, int len, long long crypto_lookup)
{
int found, n, err = 0;
struct ubifs_znode *znode;
@@ -2179,6 +2180,7 @@ int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
zbr.lnum = lnum;
zbr.offs = offs;
zbr.len = len;
+ zbr.crypto_lookup = crypto_lookup;
key_copy(c, key, &zbr.key);
err = tnc_insert(c, znode, &zbr, n + 1);
} else if (found == 1) {
@@ -2189,6 +2191,7 @@ int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
zbr->lnum = lnum;
zbr->offs = offs;
zbr->len = len;
+ zbr->crypto_lookup = crypto_lookup;
} else
err = found;
if (!err)
@@ -2207,13 +2210,15 @@ int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
* @lnum: LEB number of node
* @offs: node offset
* @len: node length
+ * @crypto_lookup: the node's updated cryptographic key's position in the KSA
*
* This function replaces a node with key @key in the TNC only if the old node
* is found. This function is called by garbage collection when node are moved.
* Returns %0 on success or negative error code on failure.
*/
int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
- int old_lnum, int old_offs, int lnum, int offs, int len)
+ int old_lnum, int old_offs, int lnum, int offs, int len,
+ long long crypto_lookup)
{
int found, n, err = 0;
struct ubifs_znode *znode;
@@ -2239,6 +2244,7 @@ int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
zbr->lnum = lnum;
zbr->offs = offs;
zbr->len = len;
+ zbr->crypto_lookup = crypto_lookup;
found = 1;
} else if (is_hash_key(c, key)) {
found = resolve_collision_directly(c, key, &znode, &n,
@@ -2476,6 +2482,7 @@ static int tnc_delete(struct ubifs_info *c, struct ubifs_znode *znode, int n)
c->zroot.lnum = zbr->lnum;
c->zroot.offs = zbr->offs;
c->zroot.len = zbr->len;
+ c->zroot.crypto_lookup = zbr->crypto_lookup;
c->zroot.znode = znode;
ubifs_assert(!ubifs_zn_obsolete(zp));
ubifs_assert(ubifs_zn_dirty(zp));
diff --git a/fs/ubifs/tnc_misc.c b/fs/ubifs/tnc_misc.c
index dc28fe6..38fdfd0 100644
--- a/fs/ubifs/tnc_misc.c
+++ b/fs/ubifs/tnc_misc.c
@@ -309,6 +309,7 @@ static int read_znode(struct ubifs_info *c, int lnum, int offs, int len,
zbr->lnum = le32_to_cpu(br->lnum);
zbr->offs = le32_to_cpu(br->offs);
zbr->len = le32_to_cpu(br->len);
+ zbr->crypto_lookup = 0;
zbr->znode = NULL;
/* Validate branch */
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index ce6d8c2..b777c0c 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -741,6 +741,7 @@ struct ubifs_jhead {
* @lnum: LEB number of the target node (indexing node or data node)
* @offs: target node offset within @lnum
* @len: target node length
+ * @crypto_lookup: the node's cryptographic key's position in the KSA
*/
struct ubifs_zbranch {
union ubifs_key key;
@@ -751,6 +752,7 @@ struct ubifs_zbranch {
int lnum;
int offs;
int len;
+ long long crypto_lookup;
};
/**
@@ -1580,9 +1582,10 @@ int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
void *node, int *lnum, int *offs);
int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
- int offs, int len);
+ int offs, int len, long long crypto_lookup);
int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
- int old_lnum, int old_offs, int lnum, int offs, int len);
+ int old_lnum, int old_offs, int lnum, int offs, int len,
+ long long crypto_lookup);
int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key,
int lnum, int offs, int len, const struct qstr *nm);
int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key);
--
1.7.5.4
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