[PATCH 14/24] ubifs: Implement encrypt/decrypt for all IO
Richard Weinberger
richard at nod.at
Thu Dec 1 13:21:01 PST 2016
Signed-off-by: Richard Weinberger <richard at nod.at>
Signed-off-by: David Gstir <david at sigma-star.at>
---
fs/ubifs/crypto.c | 51 +++++++++++++++++++++++++++++++++++
fs/ubifs/file.c | 14 ++++++++++
fs/ubifs/journal.c | 78 +++++++++++++++++++++++++++++++++++++-----------------
fs/ubifs/super.c | 6 +++--
fs/ubifs/ubifs.h | 31 ++++++++++++++++++++--
5 files changed, 152 insertions(+), 28 deletions(-)
diff --git a/fs/ubifs/crypto.c b/fs/ubifs/crypto.c
index 25bb2062b8a3..aefa3c30b73b 100644
--- a/fs/ubifs/crypto.c
+++ b/fs/ubifs/crypto.c
@@ -35,6 +35,57 @@ static int ubifs_key_prefix(struct inode *inode, u8 **key)
return sizeof(prefix) - 1;
}
+int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn,
+ unsigned int in_len, unsigned int *out_len, int block)
+{
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ void *p = &dn->data;
+ struct page *ret;
+ unsigned int pad_len = round_up(in_len, UBIFS_CIPHER_BLOCK_SIZE);
+
+ ubifs_assert(pad_len <= *out_len);
+ dn->compr_size = cpu_to_le16(in_len);
+
+ /* pad to full block cipher length */
+ if (pad_len != in_len)
+ memset(p + in_len, 0, pad_len - in_len);
+
+ ret = fscrypt_encrypt_page(inode, virt_to_page(&dn->data), pad_len,
+ offset_in_page(&dn->data), block, GFP_NOFS);
+ if (IS_ERR(ret)) {
+ ubifs_err(c, "fscrypt_encrypt_page failed: %ld", PTR_ERR(ret));
+ return PTR_ERR(ret);
+ }
+ *out_len = pad_len;
+
+ return 0;
+}
+
+int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn,
+ unsigned int *out_len, int block)
+{
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ int err;
+ unsigned int clen = le16_to_cpu(dn->compr_size);
+ unsigned int dlen = *out_len;
+
+ if (clen <= 0 || clen > UBIFS_BLOCK_SIZE || clen > dlen) {
+ ubifs_err(c, "bad compr_size: %i", clen);
+ return -EINVAL;
+ }
+
+ ubifs_assert(dlen <= UBIFS_BLOCK_SIZE);
+ err = fscrypt_decrypt_page(inode, virt_to_page(&dn->data), dlen,
+ offset_in_page(&dn->data), block);
+ if (err) {
+ ubifs_err(c, "fscrypt_decrypt_page failed: %i", err);
+ return err;
+ }
+ *out_len = clen;
+
+ return 0;
+}
+
struct fscrypt_operations ubifs_crypt_operations = {
.flags = FS_CFLG_INPLACE_ENCRYPTION,
.get_context = ubifs_crypt_get_context,
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 60e789a9cac8..4c50f8feb0d5 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -78,6 +78,13 @@ static int read_block(struct inode *inode, void *addr, unsigned int block,
goto dump;
dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
+
+ if (ubifs_crypt_is_encrypted(inode)) {
+ err = ubifs_decrypt(inode, dn, &dlen, block);
+ if (err)
+ goto dump;
+ }
+
out_len = UBIFS_BLOCK_SIZE;
err = ubifs_decompress(c, &dn->data, dlen, addr, &out_len,
le16_to_cpu(dn->compr_type));
@@ -650,6 +657,13 @@ static int populate_page(struct ubifs_info *c, struct page *page,
dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
out_len = UBIFS_BLOCK_SIZE;
+
+ if (ubifs_crypt_is_encrypted(inode)) {
+ err = ubifs_decrypt(inode, dn, &dlen, page_block);
+ if (err)
+ goto out_err;
+ }
+
err = ubifs_decompress(c, &dn->data, dlen, addr, &out_len,
le16_to_cpu(dn->compr_type));
if (err || len != out_len)
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
index b5e86c4da48f..167b9e1c80df 100644
--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -688,14 +688,18 @@ int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
const union ubifs_key *key, const void *buf, int len)
{
struct ubifs_data_node *data;
- int err, lnum, offs, compr_type, out_len;
+ int err, lnum, offs, compr_type, out_len, compr_len;
int dlen = COMPRESSED_DATA_NODE_BUF_SZ, allocated = 1;
struct ubifs_inode *ui = ubifs_inode(inode);
+ bool encrypted = ubifs_crypt_is_encrypted(inode);
dbg_jnlk(key, "ino %lu, blk %u, len %d, key ",
(unsigned long)key_inum(c, key), key_block(c, key), len);
ubifs_assert(len <= UBIFS_BLOCK_SIZE);
+ if (encrypted)
+ dlen += UBIFS_CIPHER_BLOCK_SIZE;
+
data = kmalloc(dlen, GFP_NOFS | __GFP_NOWARN);
if (!data) {
/*
@@ -720,9 +724,18 @@ int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
else
compr_type = ui->compr_type;
- out_len = dlen - UBIFS_DATA_NODE_SZ;
- ubifs_compress(c, buf, len, &data->data, &out_len, &compr_type);
- ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
+ out_len = compr_len = dlen - UBIFS_DATA_NODE_SZ;
+ ubifs_compress(c, buf, len, &data->data, &compr_len, &compr_type);
+ ubifs_assert(compr_len <= UBIFS_BLOCK_SIZE);
+
+ if (encrypted) {
+ err = ubifs_encrypt(inode, data, compr_len, &out_len, key_block(c, key));
+ if (err)
+ goto out_free;
+
+ } else {
+ data->compr_size = 0;
+ }
dlen = UBIFS_DATA_NODE_SZ + out_len;
data->compr_type = cpu_to_le16(compr_type);
@@ -1241,31 +1254,55 @@ int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
}
/**
- * recomp_data_node - re-compress a truncated data node.
+ * truncate_data_node - re-compress/encrypt a truncated data node.
+ * @c: UBIFS file-system description object
+ * @inode: inode which referes to the data node
+ * @block: data block number
* @dn: data node to re-compress
* @new_len: new length
*
* This function is used when an inode is truncated and the last data node of
- * the inode has to be re-compressed and re-written.
+ * the inode has to be re-compressed/encrypted and re-written.
*/
-static int recomp_data_node(const struct ubifs_info *c,
- struct ubifs_data_node *dn, int *new_len)
+static int truncate_data_node(const struct ubifs_info *c, const struct inode *inode,
+ unsigned int block, struct ubifs_data_node *dn,
+ int *new_len)
{
void *buf;
- int err, len, compr_type, out_len;
+ int err, dlen, compr_type, out_len, old_dlen;
out_len = le32_to_cpu(dn->size);
buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
if (!buf)
return -ENOMEM;
- len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
+ dlen = old_dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
compr_type = le16_to_cpu(dn->compr_type);
- err = ubifs_decompress(c, &dn->data, len, buf, &out_len, compr_type);
- if (err)
- goto out;
- ubifs_compress(c, buf, *new_len, &dn->data, &out_len, &compr_type);
+ if (ubifs_crypt_is_encrypted(inode)) {
+ err = ubifs_decrypt(inode, dn, &dlen, block);
+ if (err)
+ goto out;
+ }
+
+ if (compr_type != UBIFS_COMPR_NONE) {
+ err = ubifs_decompress(c, &dn->data, dlen, buf, &out_len, compr_type);
+ if (err)
+ goto out;
+
+ ubifs_compress(c, buf, *new_len, &dn->data, &out_len, &compr_type);
+ }
+
+ if (ubifs_crypt_is_encrypted(inode)) {
+ err = ubifs_encrypt(inode, dn, out_len, &old_dlen, block);
+ if (err)
+ goto out;
+
+ out_len = old_dlen;
+ } else {
+ dn->compr_size = 0;
+ }
+
ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
dn->compr_type = cpu_to_le16(compr_type);
dn->size = cpu_to_le32(*new_len);
@@ -1337,16 +1374,9 @@ int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
if (le32_to_cpu(dn->size) <= dlen)
dlen = 0; /* Nothing to do */
else {
- int compr_type = le16_to_cpu(dn->compr_type);
-
- if (compr_type != UBIFS_COMPR_NONE) {
- err = recomp_data_node(c, dn, &dlen);
- if (err)
- goto out_free;
- } else {
- dn->size = cpu_to_le32(dlen);
- dlen += UBIFS_DATA_NODE_SZ;
- }
+ err = truncate_data_node(c, inode, blk, dn, &dlen);
+ if (err)
+ goto out_free;
}
}
}
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index a31222947265..ae25c908fbe5 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1210,7 +1210,8 @@ static int mount_ubifs(struct ubifs_info *c)
bu_init(c);
if (!c->ro_mount) {
- c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ,
+ c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ + \
+ UBIFS_CIPHER_BLOCK_SIZE,
GFP_KERNEL);
if (!c->write_reserve_buf)
goto out_free;
@@ -1623,7 +1624,8 @@ static int ubifs_remount_rw(struct ubifs_info *c)
goto out;
}
- c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ, GFP_KERNEL);
+ c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ + \
+ UBIFS_CIPHER_BLOCK_SIZE, GFP_KERNEL);
if (!c->write_reserve_buf) {
err = -ENOMEM;
goto out;
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 8d61b2fc3e82..3803f833b712 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -139,6 +139,12 @@
*/
#define WORST_COMPR_FACTOR 2
+#ifdef CONFIG_UBIFS_FS_ENCRYPTION
+#define UBIFS_CIPHER_BLOCK_SIZE FS_CRYPTO_BLOCK_SIZE
+#else
+#define UBIFS_CIPHER_BLOCK_SIZE 0
+#endif
+
/*
* How much memory is needed for a buffer where we compress a data node.
*/
@@ -1783,8 +1789,6 @@ void ubifs_compress(const struct ubifs_info *c, const void *in_buf, int in_len,
int ubifs_decompress(const struct ubifs_info *c, const void *buf, int len,
void *out, int *out_len, int compr_type);
-extern struct fscrypt_operations ubifs_crypt_operations;
-
#include "debug.h"
#include "misc.h"
#include "key.h"
@@ -1812,8 +1816,31 @@ extern struct fscrypt_operations ubifs_crypt_operations;
#define fscrypt_fname_free_buffer fscrypt_notsupp_fname_free_buffer
#define fscrypt_fname_disk_to_usr fscrypt_notsupp_fname_disk_to_usr
#define fscrypt_fname_usr_to_disk fscrypt_notsupp_fname_usr_to_disk
+static inline int ubifs_encrypt(const struct inode *inode,
+ struct ubifs_data_node *dn,
+ unsigned int in_len, unsigned int *out_len,
+ int block)
+{
+ ubifs_assert(0);
+ return -EOPNOTSUPP;
+}
+static inline int ubifs_decrypt(const struct inode *inode,
+ struct ubifs_data_node *dn,
+ unsigned int *out_len, int block)
+{
+ ubifs_assert(0);
+ return -EOPNOTSUPP;
+}
+#else
+/* crypto.c */
+int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn,
+ unsigned int in_len, unsigned int *out_len, int block);
+int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn,
+ unsigned int *out_len, int block);
#endif
+extern struct fscrypt_operations ubifs_crypt_operations;
+
static inline bool __ubifs_crypt_is_encrypted(struct inode *inode)
{
struct ubifs_inode *ui = ubifs_inode(inode);
--
2.7.3
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