From: Jeff Layton <jlayton@xxxxxxxxxx>
...and allow test_dummy_encryption to bypass content encryption
if mounted with test_dummy_encryption=clear.
[ xiubli: removed the dummy enc clear mount option ]
Tested-by: Luís Henriques <lhenriques@xxxxxxx>
Tested-by: Venky Shankar <vshankar@xxxxxxxxxx>
Reviewed-by: Luís Henriques <lhenriques@xxxxxxx>
Reviewed-by: Xiubo Li <xiubli@xxxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/ceph/crypto.c | 167 +++++++++++++++++++++++++++++++++++++++++++++++
fs/ceph/crypto.h | 71 ++++++++++++++++++++
2 files changed, 238 insertions(+)
diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c
index fe47fbdaead9..21b705c2cf40 100644
--- a/fs/ceph/crypto.c
+++ b/fs/ceph/crypto.c
@@ -9,6 +9,7 @@
#include <linux/ceph/ceph_debug.h>
#include <linux/xattr.h>
#include <linux/fscrypt.h>
+#include <linux/ceph/striper.h>
#include "super.h"
#include "mds_client.h"
@@ -354,3 +355,169 @@ int ceph_fscrypt_prepare_readdir(struct inode *dir)
}
return 0;
}
+
+int ceph_fscrypt_decrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num)
+{
+ dout("%s: len %u offs %u blk %llu\n", __func__, len, offs, lblk_num);
+ return fscrypt_decrypt_block_inplace(inode, page, len, offs, lblk_num);
+}
+
+int ceph_fscrypt_encrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num, gfp_t gfp_flags)
+{
+ dout("%s: len %u offs %u blk %llu\n", __func__, len, offs, lblk_num);
+ return fscrypt_encrypt_block_inplace(inode, page, len, offs, lblk_num, gfp_flags);
+}
+
+/**
+ * ceph_fscrypt_decrypt_pages - decrypt an array of pages
+ * @inode: pointer to inode associated with these pages
+ * @page: pointer to page array
+ * @off: offset into the file that the read data starts
+ * @len: max length to decrypt
+ *
+ * Decrypt an array of fscrypt'ed pages and return the amount of
+ * data decrypted. Any data in the page prior to the start of the
+ * first complete block in the read is ignored. Any incomplete
+ * crypto blocks at the end of the array are ignored (and should
+ * probably be zeroed by the caller).
+ *
+ * Returns the length of the decrypted data or a negative errno.
+ */
+int ceph_fscrypt_decrypt_pages(struct inode *inode, struct page **page, u64 off, int len)
+{
+ int i, num_blocks;
+ u64 baseblk = off >> CEPH_FSCRYPT_BLOCK_SHIFT;
+ int ret = 0;
+
+ /*
+ * We can't deal with partial blocks on an encrypted file, so mask off
+ * the last bit.
+ */
+ num_blocks = ceph_fscrypt_blocks(off, len & CEPH_FSCRYPT_BLOCK_MASK);
+
+ /* Decrypt each block */
+ for (i = 0; i < num_blocks; ++i) {
+ int blkoff = i << CEPH_FSCRYPT_BLOCK_SHIFT;
+ int pgidx = blkoff >> PAGE_SHIFT;
+ unsigned int pgoffs = offset_in_page(blkoff);
+ int fret;
+
+ fret = ceph_fscrypt_decrypt_block_inplace(inode, page[pgidx],
+ CEPH_FSCRYPT_BLOCK_SIZE, pgoffs,
+ baseblk + i);
+ if (fret < 0) {
+ if (ret == 0)
+ ret = fret;
+ break;
+ }
+ ret += CEPH_FSCRYPT_BLOCK_SIZE;
+ }
+ return ret;
+}
+
+/**
+ * ceph_fscrypt_decrypt_extents: decrypt received extents in given buffer
+ * @inode: inode associated with pages being decrypted
+ * @page: pointer to page array
+ * @off: offset into the file that the data in page[0] starts
+ * @map: pointer to extent array
+ * @ext_cnt: length of extent array
+ *
+ * Given an extent map and a page array, decrypt the received data in-place,
+ * skipping holes. Returns the offset into buffer of end of last decrypted
+ * block.
+ */
+int ceph_fscrypt_decrypt_extents(struct inode *inode, struct page **page, u64 off,
+ struct ceph_sparse_extent *map, u32 ext_cnt)
+{
+ int i, ret = 0;
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ u64 objno, objoff;
+ u32 xlen;
+
+ /* Nothing to do for empty array */
+ if (ext_cnt == 0) {
+ dout("%s: empty array, ret 0\n", __func__);
+ return 0;
+ }
+
+ ceph_calc_file_object_mapping(&ci->i_layout, off, map[0].len,
+ &objno, &objoff, &xlen);
+
+ for (i = 0; i < ext_cnt; ++i) {
+ struct ceph_sparse_extent *ext = &map[i];
+ int pgsoff = ext->off - objoff;
+ int pgidx = pgsoff >> PAGE_SHIFT;
+ int fret;
+
+ if ((ext->off | ext->len) & ~CEPH_FSCRYPT_BLOCK_MASK) {
+ pr_warn("%s: bad encrypted sparse extent idx %d off %llx len %llx\n",
+ __func__, i, ext->off, ext->len);
+ return -EIO;
+ }
+ fret = ceph_fscrypt_decrypt_pages(inode, &page[pgidx],
+ off + pgsoff, ext->len);
+ dout("%s: [%d] 0x%llx~0x%llx fret %d\n", __func__, i,
+ ext->off, ext->len, fret);
+ if (fret < 0) {
+ if (ret == 0)
+ ret = fret;
+ break;
+ }
+ ret = pgsoff + fret;
+ }
+ dout("%s: ret %d\n", __func__, ret);
+ return ret;
+}
+
+/**
+ * ceph_fscrypt_encrypt_pages - encrypt an array of pages
+ * @inode: pointer to inode associated with these pages
+ * @page: pointer to page array
+ * @off: offset into the file that the data starts
+ * @len: max length to encrypt
+ * @gfp: gfp flags to use for allocation
+ *
+ * Decrypt an array of cleartext pages and return the amount of
+ * data encrypted. Any data in the page prior to the start of the
+ * first complete block in the read is ignored. Any incomplete
+ * crypto blocks at the end of the array are ignored.
+ *
+ * Returns the length of the encrypted data or a negative errno.
+ */
+int ceph_fscrypt_encrypt_pages(struct inode *inode, struct page **page, u64 off,
+ int len, gfp_t gfp)
+{
+ int i, num_blocks;
+ u64 baseblk = off >> CEPH_FSCRYPT_BLOCK_SHIFT;
+ int ret = 0;
+
+ /*
+ * We can't deal with partial blocks on an encrypted file, so mask off
+ * the last bit.
+ */
+ num_blocks = ceph_fscrypt_blocks(off, len & CEPH_FSCRYPT_BLOCK_MASK);
+
+ /* Encrypt each block */
+ for (i = 0; i < num_blocks; ++i) {
+ int blkoff = i << CEPH_FSCRYPT_BLOCK_SHIFT;
+ int pgidx = blkoff >> PAGE_SHIFT;
+ unsigned int pgoffs = offset_in_page(blkoff);
+ int fret;
+
+ fret = ceph_fscrypt_encrypt_block_inplace(inode, page[pgidx],
+ CEPH_FSCRYPT_BLOCK_SIZE, pgoffs,
+ baseblk + i, gfp);
+ if (fret < 0) {
+ if (ret == 0)
+ ret = fret;
+ break;
+ }
+ ret += CEPH_FSCRYPT_BLOCK_SIZE;
+ }
+ return ret;
+}
diff --git a/fs/ceph/crypto.h b/fs/ceph/crypto.h
index 80acb23d0bb4..887f191cc423 100644
--- a/fs/ceph/crypto.h
+++ b/fs/ceph/crypto.h
@@ -100,6 +100,40 @@ int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname,
struct fscrypt_str *oname, bool *is_nokey);
int ceph_fscrypt_prepare_readdir(struct inode *dir);
+static inline unsigned int ceph_fscrypt_blocks(u64 off, u64 len)
+{
+ /* crypto blocks cannot span more than one page */
+ BUILD_BUG_ON(CEPH_FSCRYPT_BLOCK_SHIFT > PAGE_SHIFT);
+
+ return ((off+len+CEPH_FSCRYPT_BLOCK_SIZE-1) >> CEPH_FSCRYPT_BLOCK_SHIFT) -
+ (off >> CEPH_FSCRYPT_BLOCK_SHIFT);
+}
+
+/*
+ * If we have an encrypted inode then we must adjust the offset and
+ * range of the on-the-wire read to cover an entire encryption block.
+ * The copy will be done using the original offset and length, after
+ * we've decrypted the result.
+ */
+static inline void ceph_fscrypt_adjust_off_and_len(struct inode *inode, u64 *off, u64 *len)
+{
+ if (IS_ENCRYPTED(inode)) {
+ *len = ceph_fscrypt_blocks(*off, *len) * CEPH_FSCRYPT_BLOCK_SIZE;
+ *off &= CEPH_FSCRYPT_BLOCK_MASK;
+ }
+}
+
+int ceph_fscrypt_decrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num);
+int ceph_fscrypt_encrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num, gfp_t gfp_flags);
+int ceph_fscrypt_decrypt_pages(struct inode *inode, struct page **page, u64 off, int len);
+int ceph_fscrypt_decrypt_extents(struct inode *inode, struct page **page, u64 off,
+ struct ceph_sparse_extent *map, u32 ext_cnt);
+int ceph_fscrypt_encrypt_pages(struct inode *inode, struct page **page, u64 off,
+ int len, gfp_t gfp);
#else /* CONFIG_FS_ENCRYPTION */
static inline void ceph_fscrypt_set_ops(struct super_block *sb)
@@ -157,6 +191,43 @@ static inline int ceph_fscrypt_prepare_readdir(struct inode *dir)
{
return 0;
}
+
+static inline void ceph_fscrypt_adjust_off_and_len(struct inode *inode, u64 *off, u64 *len)
+{
+}
+
+static inline int ceph_fscrypt_decrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num)
+{
+ return 0;
+}
+
+static inline int ceph_fscrypt_encrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num, gfp_t gfp_flags)
+{
+ return 0;
+}
+
+static inline int ceph_fscrypt_decrypt_pages(struct inode *inode, struct page **page,
+ u64 off, int len)
+{
+ return 0;
+}
+
+static inline int ceph_fscrypt_decrypt_extents(struct inode *inode, struct page **page,
+ u64 off, struct ceph_sparse_extent *map,
+ u32 ext_cnt)
+{
+ return 0;
+}
+
+static inline int ceph_fscrypt_encrypt_pages(struct inode *inode, struct page **page,
+ u64 off, int len, gfp_t gfp)
+{
+ return 0;
+}
#endif /* CONFIG_FS_ENCRYPTION */
#endif
--
2.39.1
