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Commit b3098486 authored by Michael Halcrow's avatar Michael Halcrow Committed by Theodore Ts'o
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ext4 crypto: partial update to namei.c for fname crypto 



Modifies dx_show_leaf and dx_probe to support fname encryption.
Filename encryption not yet enabled.

Signed-off-by: default avatarUday Savagaonkar <savagaon@google.com>
Signed-off-by: default avatarIldar Muslukhov <ildarm@google.com>
Signed-off-by: default avatarMichael Halcrow <mhalcrow@google.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 4bdfc873

fs/ext4/namei.c

+101 −8
Original line number Diff line number Diff line
@@ -585,7 +585,9 @@ struct stats 
	unsigned bcount;

};



static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,

static struct stats dx_show_leaf(struct inode *dir,

				struct dx_hash_info *hinfo,

				struct ext4_dir_entry_2 *de,

				int size, int show_names)

{

	unsigned names = 0, space = 0;
@@ -599,12 +601,80 @@ static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_ent 
		{

			if (show_names)

			{

#ifdef CONFIG_EXT4_FS_ENCRYPTION

				int len;

				char *name;

				struct ext4_str fname_crypto_str

					= {.name = NULL, .len = 0};

				struct ext4_fname_crypto_ctx *ctx = NULL;

				int res;



				name  = de->name;

				len = de->name_len;

				ctx = ext4_get_fname_crypto_ctx(dir,

								EXT4_NAME_LEN);

				if (IS_ERR(ctx)) {

					printk(KERN_WARNING "Error acquiring"

					" crypto ctxt--skipping crypto\n");

					ctx = NULL;

				}

				if (ctx == NULL) {

					/* Directory is not encrypted */

					ext4fs_dirhash(de->name,

						de->name_len, &h);

					printk("%*.s:(U)%x.%u ", len,

					       name, h.hash,

					       (unsigned) ((char *) de

							   - base));

				} else {

					/* Directory is encrypted */

					res = ext4_fname_crypto_alloc_buffer(

						ctx, de->name_len,

						&fname_crypto_str);

					if (res < 0) {

						printk(KERN_WARNING "Error "

							"allocating crypto "

							"buffer--skipping "

							"crypto\n");

						ext4_put_fname_crypto_ctx(&ctx);

						ctx = NULL;

					}

					res = ext4_fname_disk_to_usr(ctx, de,

							&fname_crypto_str);

					if (res < 0) {

						printk(KERN_WARNING "Error "

							"converting filename "

							"from disk to usr"

							"\n");

						name = "??";

						len = 2;

					} else {

						name = fname_crypto_str.name;

						len = fname_crypto_str.len;

					}

					res = ext4_fname_disk_to_hash(ctx, de,

								      &h);

					if (res < 0) {

						printk(KERN_WARNING "Error "

							"converting filename "

							"from disk to htree"

							"\n");

						h.hash = 0xDEADBEEF;

					}

					printk("%*.s:(E)%x.%u ", len, name,

					       h.hash, (unsigned) ((char *) de

								   - base));

					ext4_put_fname_crypto_ctx(&ctx);

					ext4_fname_crypto_free_buffer(

						&fname_crypto_str);

				}

#else

				int len = de->name_len;

				char *name = de->name;

				while (len--) printk("%c", *name++);

				ext4fs_dirhash(de->name, de->name_len, &h);

				printk(":%x.%u ", h.hash,

				printk("%*.s:%x.%u ", len, name, h.hash,

				       (unsigned) ((char *) de - base));

#endif

			}

			space += EXT4_DIR_REC_LEN(de->name_len);

			names++;
@@ -622,7 +692,6 @@ struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 
	unsigned count = dx_get_count(entries), names = 0, space = 0, i;

	unsigned bcount = 0;

	struct buffer_head *bh;

	int err;

	printk("%i indexed blocks...\n", count);

	for (i = 0; i < count; i++, entries++)

	{
@@ -636,7 +705,8 @@ struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 
			continue;

		stats = levels?

		   dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):

		   dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);

		   dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)

			bh->b_data, blocksize, 0);

		names += stats.names;

		space += stats.space;

		bcount += stats.bcount;
@@ -686,8 +756,28 @@ dx_probe(const struct qstr *d_name, struct inode *dir, 
	if (hinfo->hash_version <= DX_HASH_TEA)

		hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;

	hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;

#ifdef CONFIG_EXT4_FS_ENCRYPTION

	if (d_name) {

		struct ext4_fname_crypto_ctx *ctx = NULL;

		int res;



		/* Check if the directory is encrypted */

		ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN);

		if (IS_ERR(ctx)) {

			ret_err = ERR_PTR(PTR_ERR(ctx));

			goto fail;

		}

		res = ext4_fname_usr_to_hash(ctx, d_name, hinfo);

		if (res < 0) {

			ret_err = ERR_PTR(res);

			goto fail;

		}

		ext4_put_fname_crypto_ctx(&ctx);

	}

#else

	if (d_name)

		ext4fs_dirhash(d_name->name, d_name->len, hinfo);

#endif

	hash = hinfo->hash;



	if (root->info.unused_flags & 1) {
@@ -772,6 +862,7 @@ dx_probe(const struct qstr *d_name, struct inode *dir, 
		brelse(frame->bh);

		frame--;

	}



	if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))

		ext4_warning(dir->i_sb,

			     "Corrupt dir inode %lu, running e2fsck is "
@@ -1604,8 +1695,10 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 
		initialize_dirent_tail(t, blocksize);

	}



	dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));

	dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));

	dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,

			blocksize, 1));

	dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,

			blocksize, 1));



	/* Which block gets the new entry? */

	if (hinfo->hash >= hash2) {