...and allow test_dummy_encryption to bypass content encryption
if mounted with test_dummy_encryption=clear.
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/ceph/crypto.c | 121 +++++++++++++++++++++++++++++++++++++++++++++++
fs/ceph/crypto.h | 66 ++++++++++++++++++++++++++
fs/ceph/super.c | 8 ++++
fs/ceph/super.h | 1 +
4 files changed, 196 insertions(+)
diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c
index 35137beb027b..5a87e7385d3f 100644
--- a/fs/ceph/crypto.c
+++ b/fs/ceph/crypto.c
@@ -251,3 +251,124 @@ int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname,
fscrypt_fname_free_buffer(&_tname);
return ret;
}
+
+int ceph_fscrypt_decrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num)
+{
+ struct ceph_mount_options *opt = ceph_inode_to_client(inode)->mount_options;
+
+ if (opt->flags & CEPH_MOUNT_OPT_DUMMY_ENC_CLEAR)
+ return 0;
+
+ 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)
+{
+ struct ceph_mount_options *opt = ceph_inode_to_client(inode)->mount_options;
+
+ if (opt->flags & CEPH_MOUNT_OPT_DUMMY_ENC_CLEAR)
+ return 0;
+
+ 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_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 ab27a7ed62c3..b5d360085fe8 100644
--- a/fs/ceph/crypto.h
+++ b/fs/ceph/crypto.h
@@ -31,6 +31,10 @@ struct ceph_fscrypt_auth {
u8 cfa_blob[FSCRYPT_SET_CONTEXT_MAX_SIZE];
} __packed;
+#define CEPH_FSCRYPT_BLOCK_SHIFT 12
+#define CEPH_FSCRYPT_BLOCK_SIZE (_AC(1,UL) << CEPH_FSCRYPT_BLOCK_SHIFT)
+#define CEPH_FSCRYPT_BLOCK_MASK (~(CEPH_FSCRYPT_BLOCK_SIZE-1))
+
#define CEPH_FSCRYPT_AUTH_VERSION 1
static inline u32 ceph_fscrypt_auth_len(struct ceph_fscrypt_auth *fa)
{
@@ -83,6 +87,38 @@ static inline void ceph_fname_free_buffer(struct inode *parent, struct fscrypt_s
int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname,
struct fscrypt_str *oname, bool *is_nokey);
+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 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_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)
@@ -128,6 +164,36 @@ static inline int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscry
oname->len = fname->name_len;
return 0;
}
+
+static inline void 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_encrypt_pages(struct inode *inode, struct page **page,
+ u64 off, int len, gfp_t gfp)
+{
+ return 0;
+}
#endif /* CONFIG_FS_ENCRYPTION */
#endif
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 0b32d31c6fe0..10923d75a876 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -1076,6 +1076,14 @@ static int ceph_set_test_dummy_encryption(struct super_block *sb, struct fs_cont
return -EEXIST;
}
+ /* HACK: allow for cleartext "encryption" in files for testing */
+ if (fsc->mount_options->test_dummy_encryption &&
+ !strcmp(fsc->mount_options->test_dummy_encryption, "clear")) {
+ fsopt->flags |= CEPH_MOUNT_OPT_DUMMY_ENC_CLEAR;
+ kfree(fsc->mount_options->test_dummy_encryption);
+ fsc->mount_options->test_dummy_encryption = NULL;
+ }
+
err = fscrypt_set_test_dummy_encryption(sb,
fsc->mount_options->test_dummy_encryption,
&fsc->dummy_enc_policy);
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index c17622778720..4d2ccb51fe61 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -50,6 +50,7 @@
#define CEPH_MOUNT_OPT_ASYNC_DIROPS (1<<15) /* allow async directory ops */
#define CEPH_MOUNT_OPT_NOPAGECACHE (1<<16) /* bypass pagecache altogether */
#define CEPH_MOUNT_OPT_TEST_DUMMY_ENC (1<<17) /* enable dummy encryption (for testing) */
+#define CEPH_MOUNT_OPT_DUMMY_ENC_CLEAR (1<<18) /* don't actually encrypt content */
#define CEPH_MOUNT_OPT_DEFAULT \
(CEPH_MOUNT_OPT_DCACHE | \
--
2.34.1
