ubifs: Implement encrypt/decrypt for all IO

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>

diff --git a/fs/ubifs/crypto.c b/fs/ubifs/crypto.c
index 25bb2062b8a392ff38ecb03d636b09270b5ac418..aefa3c30b73bd629b0add4aa944cb86728cf2403 100644 (file)
--- 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 60e789a9cac85f142d093b472a51aeee7cbf08c4..4c50f8feb0d5495ad7ad3cedde952a2f86050b41 100644 (file)
--- 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 b5e86c4da48f1911af8451c57033ef69078704e8..167b9e1c80df21ce5b9b335c1fce4358ef3bea35 100644 (file)
--- 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 @@ out_free:
 }
 
 /**
- * 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 a312229472658b235997e5b48f58fcc59dd69939..ae25c908fbe50e4c746c762013a3b6be74e631c8 100644 (file)
--- 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 74a8def1f7b73573d8f8ea7d816cac989b9dbd90..2df3c0d210209301bfd5f4c25918563bb02b7c3d 100644 (file)
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -135,6 +135,12 @@
  */
 #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.
  */
@@ -1774,8 +1780,6 @@ 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"
@@ -1803,8 +1807,31 @@ 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);