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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/ceph/crypto.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'fs/ceph/crypto.c')
-rw-r--r--fs/ceph/crypto.c605
1 files changed, 605 insertions, 0 deletions
diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c
new file mode 100644
index 000000000..64d240759
--- /dev/null
+++ b/fs/ceph/crypto.c
@@ -0,0 +1,605 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * The base64 encode/decode code was copied from fscrypt:
+ * Copyright (C) 2015, Google, Inc.
+ * Copyright (C) 2015, Motorola Mobility
+ * Written by Uday Savagaonkar, 2014.
+ * Modified by Jaegeuk Kim, 2015.
+ */
+#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"
+#include "crypto.h"
+
+static int ceph_crypt_get_context(struct inode *inode, void *ctx, size_t len)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_fscrypt_auth *cfa = (struct ceph_fscrypt_auth *)ci->fscrypt_auth;
+ u32 ctxlen;
+
+ /* Non existent or too short? */
+ if (!cfa || (ci->fscrypt_auth_len < (offsetof(struct ceph_fscrypt_auth, cfa_blob) + 1)))
+ return -ENOBUFS;
+
+ /* Some format we don't recognize? */
+ if (le32_to_cpu(cfa->cfa_version) != CEPH_FSCRYPT_AUTH_VERSION)
+ return -ENOBUFS;
+
+ ctxlen = le32_to_cpu(cfa->cfa_blob_len);
+ if (len < ctxlen)
+ return -ERANGE;
+
+ memcpy(ctx, cfa->cfa_blob, ctxlen);
+ return ctxlen;
+}
+
+static int ceph_crypt_set_context(struct inode *inode, const void *ctx,
+ size_t len, void *fs_data)
+{
+ int ret;
+ struct iattr attr = { };
+ struct ceph_iattr cia = { };
+ struct ceph_fscrypt_auth *cfa;
+
+ WARN_ON_ONCE(fs_data);
+
+ if (len > FSCRYPT_SET_CONTEXT_MAX_SIZE)
+ return -EINVAL;
+
+ cfa = kzalloc_obj(*cfa);
+ if (!cfa)
+ return -ENOMEM;
+
+ cfa->cfa_version = cpu_to_le32(CEPH_FSCRYPT_AUTH_VERSION);
+ cfa->cfa_blob_len = cpu_to_le32(len);
+ memcpy(cfa->cfa_blob, ctx, len);
+
+ cia.fscrypt_auth = cfa;
+
+ ret = __ceph_setattr(&nop_mnt_idmap, inode, &attr, &cia);
+ if (ret == 0)
+ inode_set_flags(inode, S_ENCRYPTED, S_ENCRYPTED);
+ kfree(cia.fscrypt_auth);
+ return ret;
+}
+
+static bool ceph_crypt_empty_dir(struct inode *inode)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+
+ return ci->i_rsubdirs + ci->i_rfiles == 1;
+}
+
+static const union fscrypt_policy *ceph_get_dummy_policy(struct super_block *sb)
+{
+ return ceph_sb_to_fs_client(sb)->fsc_dummy_enc_policy.policy;
+}
+
+static struct fscrypt_operations ceph_fscrypt_ops = {
+ .inode_info_offs = (int)offsetof(struct ceph_inode_info, i_crypt_info) -
+ (int)offsetof(struct ceph_inode_info, netfs.inode),
+ .needs_bounce_pages = 1,
+ .get_context = ceph_crypt_get_context,
+ .set_context = ceph_crypt_set_context,
+ .get_dummy_policy = ceph_get_dummy_policy,
+ .empty_dir = ceph_crypt_empty_dir,
+};
+
+void ceph_fscrypt_set_ops(struct super_block *sb)
+{
+ fscrypt_set_ops(sb, &ceph_fscrypt_ops);
+}
+
+void ceph_fscrypt_free_dummy_policy(struct ceph_fs_client *fsc)
+{
+ fscrypt_free_dummy_policy(&fsc->fsc_dummy_enc_policy);
+}
+
+int ceph_fscrypt_prepare_context(struct inode *dir, struct inode *inode,
+ struct ceph_acl_sec_ctx *as)
+{
+ int ret, ctxsize;
+ bool encrypted = false;
+ struct ceph_inode_info *ci = ceph_inode(inode);
+
+ ret = fscrypt_prepare_new_inode(dir, inode, &encrypted);
+ if (ret)
+ return ret;
+ if (!encrypted)
+ return 0;
+
+ as->fscrypt_auth = kzalloc_obj(*as->fscrypt_auth);
+ if (!as->fscrypt_auth)
+ return -ENOMEM;
+
+ ctxsize = fscrypt_context_for_new_inode(as->fscrypt_auth->cfa_blob,
+ inode);
+ if (ctxsize < 0)
+ return ctxsize;
+
+ as->fscrypt_auth->cfa_version = cpu_to_le32(CEPH_FSCRYPT_AUTH_VERSION);
+ as->fscrypt_auth->cfa_blob_len = cpu_to_le32(ctxsize);
+
+ WARN_ON_ONCE(ci->fscrypt_auth);
+ kfree(ci->fscrypt_auth);
+ ci->fscrypt_auth_len = ceph_fscrypt_auth_len(as->fscrypt_auth);
+ ci->fscrypt_auth = kmemdup(as->fscrypt_auth, ci->fscrypt_auth_len,
+ GFP_KERNEL);
+ if (!ci->fscrypt_auth)
+ return -ENOMEM;
+
+ inode->i_flags |= S_ENCRYPTED;
+
+ return 0;
+}
+
+void ceph_fscrypt_as_ctx_to_req(struct ceph_mds_request *req,
+ struct ceph_acl_sec_ctx *as)
+{
+ swap(req->r_fscrypt_auth, as->fscrypt_auth);
+}
+
+/*
+ * User-created snapshots can't start with '_'. Snapshots that start with this
+ * character are special (hint: there aren't real snapshots) and use the
+ * following format:
+ *
+ * _<SNAPSHOT-NAME>_<INODE-NUMBER>
+ *
+ * where:
+ * - <SNAPSHOT-NAME> - the real snapshot name that may need to be decrypted,
+ * - <INODE-NUMBER> - the inode number (in decimal) for the actual snapshot
+ *
+ * This function parses these snapshot names and returns the inode
+ * <INODE-NUMBER>. 'name_len' will also bet set with the <SNAPSHOT-NAME>
+ * length.
+ */
+static struct inode *parse_longname(const struct inode *parent,
+ const char *name, int *name_len)
+{
+ struct ceph_client *cl = ceph_inode_to_client(parent);
+ struct inode *dir = NULL;
+ struct ceph_vino vino = { .snap = CEPH_NOSNAP };
+ char *name_end, *inode_number;
+ int ret = -EIO;
+ /* Snapshot name must start with an underscore */
+ if (*name_len <= 0 || name[0] != '_')
+ return ERR_PTR(-EIO);
+ /* Skip initial '_' and NUL-terminate */
+ char *str __free(kfree) = kmemdup_nul(name + 1, *name_len - 1, GFP_KERNEL);
+ if (!str)
+ return ERR_PTR(-ENOMEM);
+ name_end = strrchr(str, '_');
+ if (!name_end) {
+ doutc(cl, "failed to parse long snapshot name: %s\n", str);
+ return ERR_PTR(-EIO);
+ }
+ *name_len = (name_end - str);
+ if (*name_len <= 0) {
+ pr_err_client(cl, "failed to parse long snapshot name\n");
+ return ERR_PTR(-EIO);
+ }
+
+ /* Get the inode number */
+ inode_number = name_end + 1;
+ ret = kstrtou64(inode_number, 10, &vino.ino);
+ if (ret) {
+ doutc(cl, "failed to parse inode number: %s\n", str);
+ return ERR_PTR(ret);
+ }
+
+ /* And finally the inode */
+ dir = ceph_find_inode(parent->i_sb, vino);
+ if (!dir) {
+ /* This can happen if we're not mounting cephfs on the root */
+ dir = ceph_get_inode(parent->i_sb, vino, NULL);
+ if (IS_ERR(dir))
+ doutc(cl, "can't find inode %s (%s)\n", inode_number, name);
+ }
+ return dir;
+}
+
+int ceph_encode_encrypted_dname(struct inode *parent, char *buf, int elen)
+{
+ struct ceph_client *cl = ceph_inode_to_client(parent);
+ struct inode *dir = parent;
+ char *p = buf;
+ u32 len;
+ int name_len = elen;
+ int ret;
+ u8 *cryptbuf = NULL;
+
+ /* Handle the special case of snapshot names that start with '_' */
+ if (ceph_snap(dir) == CEPH_SNAPDIR && *p == '_') {
+ dir = parse_longname(parent, p, &name_len);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+ p++; /* skip initial '_' */
+ }
+
+ if (!fscrypt_has_encryption_key(dir))
+ goto out;
+
+ /*
+ * Convert cleartext d_name to ciphertext. If result is longer than
+ * CEPH_NOHASH_NAME_MAX, sha256 the remaining bytes
+ *
+ * See: fscrypt_setup_filename
+ */
+ if (!fscrypt_fname_encrypted_size(dir, name_len, NAME_MAX, &len)) {
+ elen = -ENAMETOOLONG;
+ goto out;
+ }
+
+ /* Allocate a buffer appropriate to hold the result */
+ cryptbuf = kmalloc(len > CEPH_NOHASH_NAME_MAX ? NAME_MAX : len,
+ GFP_KERNEL);
+ if (!cryptbuf) {
+ elen = -ENOMEM;
+ goto out;
+ }
+
+ ret = fscrypt_fname_encrypt(dir,
+ &(struct qstr)QSTR_INIT(p, name_len),
+ cryptbuf, len);
+ if (ret) {
+ elen = ret;
+ goto out;
+ }
+
+ /* hash the end if the name is long enough */
+ if (len > CEPH_NOHASH_NAME_MAX) {
+ u8 hash[SHA256_DIGEST_SIZE];
+ u8 *extra = cryptbuf + CEPH_NOHASH_NAME_MAX;
+
+ /*
+ * hash the extra bytes and overwrite crypttext beyond that
+ * point with it
+ */
+ sha256(extra, len - CEPH_NOHASH_NAME_MAX, hash);
+ memcpy(extra, hash, SHA256_DIGEST_SIZE);
+ len = CEPH_NOHASH_NAME_MAX + SHA256_DIGEST_SIZE;
+ }
+
+ /* base64 encode the encrypted name */
+ elen = base64_encode(cryptbuf, len, p, false, BASE64_IMAP);
+ doutc(cl, "base64-encoded ciphertext name = %.*s\n", elen, p);
+
+ /* To understand the 240 limit, see CEPH_NOHASH_NAME_MAX comments */
+ WARN_ON(elen > 240);
+ if (dir != parent) // leading _ is already there; append _<inum>
+ elen += 1 + sprintf(p + elen, "_%llu", dir->i_ino);
+
+out:
+ kfree(cryptbuf);
+ if (dir != parent) {
+ if ((inode_state_read_once(dir) & I_NEW))
+ discard_new_inode(dir);
+ else
+ iput(dir);
+ }
+ return elen;
+}
+
+/**
+ * ceph_fname_to_usr - convert a filename for userland presentation
+ * @fname: ceph_fname to be converted
+ * @tname: temporary name buffer to use for conversion (may be NULL)
+ * @oname: where converted name should be placed
+ * @is_nokey: set to true if key wasn't available during conversion (may be NULL)
+ *
+ * Given a filename (usually from the MDS), format it for presentation to
+ * userland. If @parent is not encrypted, just pass it back as-is.
+ *
+ * Otherwise, base64 decode the string, and then ask fscrypt to format it
+ * for userland presentation.
+ *
+ * Returns 0 on success or negative error code on error.
+ */
+int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname,
+ struct fscrypt_str *oname, bool *is_nokey)
+{
+ struct inode *dir = fname->dir;
+ struct fscrypt_str _tname = FSTR_INIT(NULL, 0);
+ struct fscrypt_str iname;
+ char *name = fname->name;
+ int name_len = fname->name_len;
+ int ret;
+
+ /* Sanity check that the resulting name will fit in the buffer */
+ if (fname->name_len > NAME_MAX || fname->ctext_len > NAME_MAX)
+ return -EIO;
+
+ /* Handle the special case of snapshot names that start with '_' */
+ if ((ceph_snap(dir) == CEPH_SNAPDIR) && (name_len > 0) &&
+ (name[0] == '_')) {
+ dir = parse_longname(dir, name, &name_len);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+ name++; /* skip initial '_' */
+ }
+
+ if (!IS_ENCRYPTED(dir)) {
+ oname->name = fname->name;
+ oname->len = fname->name_len;
+ ret = 0;
+ goto out_inode;
+ }
+
+ ret = ceph_fscrypt_prepare_readdir(dir);
+ if (ret)
+ goto out_inode;
+
+ /*
+ * Use the raw dentry name as sent by the MDS instead of
+ * generating a nokey name via fscrypt.
+ */
+ if (!fscrypt_has_encryption_key(dir)) {
+ if (fname->no_copy)
+ oname->name = fname->name;
+ else
+ memcpy(oname->name, fname->name, fname->name_len);
+ oname->len = fname->name_len;
+ if (is_nokey)
+ *is_nokey = true;
+ ret = 0;
+ goto out_inode;
+ }
+
+ if (fname->ctext_len == 0) {
+ int declen;
+
+ if (!tname) {
+ ret = fscrypt_fname_alloc_buffer(NAME_MAX, &_tname);
+ if (ret)
+ goto out_inode;
+ tname = &_tname;
+ }
+
+ declen = base64_decode(name, name_len,
+ tname->name, false, BASE64_IMAP);
+ if (declen <= 0) {
+ ret = -EIO;
+ goto out;
+ }
+ iname.name = tname->name;
+ iname.len = declen;
+ } else {
+ iname.name = fname->ctext;
+ iname.len = fname->ctext_len;
+ }
+
+ ret = fscrypt_fname_disk_to_usr(dir, 0, 0, &iname, oname);
+ if (!ret && (dir != fname->dir)) {
+ char tmp_buf[BASE64_CHARS(NAME_MAX)];
+
+ name_len = snprintf(tmp_buf, sizeof(tmp_buf), "_%.*s_%llu",
+ oname->len, oname->name, dir->i_ino);
+ memcpy(oname->name, tmp_buf, name_len);
+ oname->len = name_len;
+ }
+
+out:
+ fscrypt_fname_free_buffer(&_tname);
+out_inode:
+ if (dir != fname->dir) {
+ if ((inode_state_read_once(dir) & I_NEW))
+ discard_new_inode(dir);
+ else
+ iput(dir);
+ }
+ return ret;
+}
+
+/**
+ * ceph_fscrypt_prepare_readdir - simple __fscrypt_prepare_readdir() wrapper
+ * @dir: directory inode for readdir prep
+ *
+ * Simple wrapper around __fscrypt_prepare_readdir() that will mark directory as
+ * non-complete if this call results in having the directory unlocked.
+ *
+ * Returns:
+ * 1 - if directory was locked and key is now loaded (i.e. dir is unlocked)
+ * 0 - if directory is still locked
+ * < 0 - if __fscrypt_prepare_readdir() fails
+ */
+int ceph_fscrypt_prepare_readdir(struct inode *dir)
+{
+ bool had_key = fscrypt_has_encryption_key(dir);
+ int err;
+
+ if (!IS_ENCRYPTED(dir))
+ return 0;
+
+ err = __fscrypt_prepare_readdir(dir);
+ if (err)
+ return err;
+ if (!had_key && fscrypt_has_encryption_key(dir)) {
+ /* directory just got unlocked, mark it as not complete */
+ ceph_dir_clear_complete(dir);
+ return 1;
+ }
+ return 0;
+}
+
+int ceph_fscrypt_decrypt_block_inplace(const struct inode *inode,
+ struct page *page, unsigned int len,
+ unsigned int offs, u64 lblk_num)
+{
+ struct ceph_client *cl = ceph_inode_to_client(inode);
+
+ doutc(cl, "%p %llx.%llx len %u offs %u blk %llu\n", inode,
+ ceph_vinop(inode), 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)
+{
+ struct ceph_client *cl = ceph_inode_to_client(inode);
+
+ doutc(cl, "%p %llx.%llx len %u offs %u blk %llu\n", inode,
+ ceph_vinop(inode), len, offs, lblk_num);
+ return fscrypt_encrypt_block_inplace(inode, page, len, offs, lblk_num);
+}
+
+/**
+ * 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)
+{
+ struct ceph_client *cl = ceph_inode_to_client(inode);
+ 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) {
+ doutc(cl, "%p %llx.%llx empty array, ret 0\n", inode,
+ ceph_vinop(inode));
+ 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_client(cl,
+ "%p %llx.%llx bad encrypted sparse extent "
+ "idx %d off %llx len %llx\n",
+ inode, ceph_vinop(inode), i, ext->off,
+ ext->len);
+ return -EIO;
+ }
+ fret = ceph_fscrypt_decrypt_pages(inode, &page[pgidx],
+ off + pgsoff, ext->len);
+ doutc(cl, "%p %llx.%llx [%d] 0x%llx~0x%llx fret %d\n", inode,
+ ceph_vinop(inode), i, ext->off, ext->len, fret);
+ if (fret < 0) {
+ if (ret == 0)
+ ret = fret;
+ break;
+ }
+ ret = pgsoff + fret;
+ }
+ doutc(cl, "ret %d\n", 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
+ *
+ * Encrypt 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)
+{
+ 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);
+ if (fret < 0) {
+ if (ret == 0)
+ ret = fret;
+ break;
+ }
+ ret += CEPH_FSCRYPT_BLOCK_SIZE;
+ }
+ return ret;
+}