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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#include <linux/file.h>#include <linux/vmalloc.h>#include <linux/pagemap.h>#include <linux/dcache.h>#include <linux/namei.h>#include <linux/mount.h>#include <linux/fs_stack.h>#include <linux/slab.h>#include <linux/xattr.h>#include <linux/posix_acl.h>#include <linux/posix_acl_xattr.h>#include <linux/fileattr.h>#include <linux/unaligned.h>#include "ecryptfs_kernel.h"
static struct dentry *ecryptfs_start_creating_dentry(struct dentry *dentry){ struct dentry *parent = dget_parent(dentry); struct dentry *ret;
ret = start_creating_dentry(ecryptfs_dentry_to_lower(parent), ecryptfs_dentry_to_lower(dentry)); dput(parent); return ret;}
static struct dentry *ecryptfs_start_removing_dentry(struct dentry *dentry){ struct dentry *parent = dget_parent(dentry); struct dentry *ret;
ret = start_removing_dentry(ecryptfs_dentry_to_lower(parent), ecryptfs_dentry_to_lower(dentry)); dput(parent); return ret;}
static int ecryptfs_inode_test(struct inode *inode, void *lower_inode){ return ecryptfs_inode_to_lower(inode) == lower_inode;}
static int ecryptfs_inode_set(struct inode *inode, void *opaque){ struct inode *lower_inode = opaque;
ecryptfs_set_inode_lower(inode, lower_inode); fsstack_copy_attr_all(inode, lower_inode); /* i_size will be overwritten for encrypted regular files */ fsstack_copy_inode_size(inode, lower_inode); inode->i_ino = lower_inode->i_ino; inode->i_mapping->a_ops = &ecryptfs_aops;
if (S_ISLNK(inode->i_mode)) inode->i_op = &ecryptfs_symlink_iops; else if (S_ISDIR(inode->i_mode)) inode->i_op = &ecryptfs_dir_iops; else inode->i_op = &ecryptfs_main_iops;
if (S_ISDIR(inode->i_mode)) inode->i_fop = &ecryptfs_dir_fops; else if (special_file(inode->i_mode)) init_special_inode(inode, inode->i_mode, inode->i_rdev); else inode->i_fop = &ecryptfs_main_fops;
return 0;}
static struct inode *__ecryptfs_get_inode(struct inode *lower_inode, struct super_block *sb){ struct inode *inode;
if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb)) return ERR_PTR(-EXDEV);
/* Reject dealing with casefold directories. */ if (IS_CASEFOLDED(lower_inode)) { pr_err_ratelimited("%s: Can't handle casefolded directory.\n", __func__); return ERR_PTR(-EREMOTE); }
if (!igrab(lower_inode)) return ERR_PTR(-ESTALE); inode = iget5_locked(sb, (unsigned long)lower_inode, ecryptfs_inode_test, ecryptfs_inode_set, lower_inode); if (!inode) { iput(lower_inode); return ERR_PTR(-EACCES); } if (!(inode_state_read_once(inode) & I_NEW)) iput(lower_inode);
return inode;}
struct inode *ecryptfs_get_inode(struct inode *lower_inode, struct super_block *sb){ struct inode *inode = __ecryptfs_get_inode(lower_inode, sb);
if (!IS_ERR(inode) && (inode_state_read_once(inode) & I_NEW)) unlock_new_inode(inode);
return inode;}
/** * ecryptfs_interpose * @lower_dentry: Existing dentry in the lower filesystem * @dentry: ecryptfs' dentry * @sb: ecryptfs's super_block * * Interposes upper and lower dentries. * * Returns zero on success; non-zero otherwise */static int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry, struct super_block *sb){ struct inode *inode = ecryptfs_get_inode(d_inode(lower_dentry), sb);
if (IS_ERR(inode)) return PTR_ERR(inode); d_instantiate(dentry, inode);
return 0;}
static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry, struct inode *inode){ struct dentry *lower_dentry; struct inode *lower_dir; int rc;
lower_dentry = ecryptfs_start_removing_dentry(dentry); if (IS_ERR(lower_dentry)) return PTR_ERR(lower_dentry);
lower_dir = lower_dentry->d_parent->d_inode; rc = vfs_unlink(&nop_mnt_idmap, lower_dir, lower_dentry, NULL); if (rc) { printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); goto out_unlock; } fsstack_copy_attr_times(dir, lower_dir); set_nlink(inode, ecryptfs_inode_to_lower(inode)->i_nlink); inode_set_ctime_to_ts(inode, inode_get_ctime(dir));out_unlock: end_removing(lower_dentry); if (!rc) d_drop(dentry); return rc;}
/** * ecryptfs_do_create * @directory_inode: inode of the new file's dentry's parent in ecryptfs * @ecryptfs_dentry: New file's dentry in ecryptfs * @mode: The mode of the new file * * Creates the underlying file and the eCryptfs inode which will link to * it. It will also update the eCryptfs directory inode to mimic the * stat of the lower directory inode. * * Returns the new eCryptfs inode on success; an ERR_PTR on error condition */static struct inode *ecryptfs_do_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, umode_t mode){ int rc; struct dentry *lower_dentry; struct inode *lower_dir; struct inode *inode;
lower_dentry = ecryptfs_start_creating_dentry(ecryptfs_dentry); if (IS_ERR(lower_dentry)) return ERR_CAST(lower_dentry); lower_dir = lower_dentry->d_parent->d_inode; rc = vfs_create(&nop_mnt_idmap, lower_dentry, mode, NULL); if (rc) { printk(KERN_ERR "%s: Failure to create dentry in lower fs; " "rc = [%d]\n", __func__, rc); inode = ERR_PTR(rc); goto out_lock; } inode = __ecryptfs_get_inode(d_inode(lower_dentry), directory_inode->i_sb); if (IS_ERR(inode)) { vfs_unlink(&nop_mnt_idmap, lower_dir, lower_dentry, NULL); goto out_lock; } fsstack_copy_attr_times(directory_inode, lower_dir); fsstack_copy_inode_size(directory_inode, lower_dir);out_lock: end_creating(lower_dentry); return inode;}
/* * ecryptfs_initialize_file * * Cause the file to be changed from a basic empty file to an ecryptfs * file with a header and first data page. * * Returns zero on success */int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry, struct inode *ecryptfs_inode){ struct ecryptfs_crypt_stat *crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; int rc = 0;
if (S_ISDIR(ecryptfs_inode->i_mode)) { ecryptfs_printk(KERN_DEBUG, "This is a directory\n"); crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); goto out; } ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n"); rc = ecryptfs_new_file_context(ecryptfs_inode); if (rc) { ecryptfs_printk(KERN_ERR, "Error creating new file " "context; rc = [%d]\n", rc); goto out; } rc = ecryptfs_get_lower_file(ecryptfs_dentry, ecryptfs_inode); if (rc) { printk(KERN_ERR "%s: Error attempting to initialize " "the lower file for the dentry with name " "[%pd]; rc = [%d]\n", __func__, ecryptfs_dentry, rc); goto out; } rc = ecryptfs_write_metadata(ecryptfs_dentry, ecryptfs_inode); if (rc) printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc); ecryptfs_put_lower_file(ecryptfs_inode);out: return rc;}
/* * ecryptfs_create * @mode: The mode of the new file. * * Creates a new file. * * Returns zero on success; non-zero on error condition */static intecryptfs_create(struct mnt_idmap *idmap, struct inode *directory_inode, struct dentry *ecryptfs_dentry, umode_t mode, bool excl){ struct inode *ecryptfs_inode; int rc;
ecryptfs_inode = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode); if (IS_ERR(ecryptfs_inode)) { ecryptfs_printk(KERN_WARNING, "Failed to create file in" "lower filesystem\n"); rc = PTR_ERR(ecryptfs_inode); goto out; } /* At this point, a file exists on "disk"; we need to make sure * that this on disk file is prepared to be an ecryptfs file */ rc = ecryptfs_initialize_file(ecryptfs_dentry, ecryptfs_inode); if (rc) { ecryptfs_do_unlink(directory_inode, ecryptfs_dentry, ecryptfs_inode); iget_failed(ecryptfs_inode); goto out; } d_instantiate_new(ecryptfs_dentry, ecryptfs_inode);out: return rc;}
static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode){ struct ecryptfs_crypt_stat *crypt_stat; int rc;
rc = ecryptfs_get_lower_file(dentry, inode); if (rc) { printk(KERN_ERR "%s: Error attempting to initialize " "the lower file for the dentry with name " "[%pd]; rc = [%d]\n", __func__, dentry, rc); return rc; }
crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; /* TODO: lock for crypt_stat comparison */ if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) ecryptfs_set_default_sizes(crypt_stat);
rc = ecryptfs_read_and_validate_header_region(inode); ecryptfs_put_lower_file(inode); if (rc) { rc = ecryptfs_read_and_validate_xattr_region(dentry, inode); if (!rc) crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; }
/* Must return 0 to allow non-eCryptfs files to be looked up, too */ return 0;}
/* * ecryptfs_lookup_interpose - Dentry interposition for a lookup */static struct dentry *ecryptfs_lookup_interpose(struct dentry *dentry, struct dentry *lower_dentry){ struct dentry *lower_parent = ecryptfs_dentry_to_lower(dentry->d_parent); struct inode *inode, *lower_inode; int rc = 0;
fsstack_copy_attr_atime(d_inode(dentry->d_parent), d_inode(lower_parent)); BUG_ON(!d_count(lower_dentry));
ecryptfs_set_dentry_lower(dentry, lower_dentry);
/* * negative dentry can go positive under us here - its parent is not * locked. That's OK and that could happen just as we return from * ecryptfs_lookup() anyway. Just need to be careful and fetch * ->d_inode only once - it's not stable here. */ lower_inode = READ_ONCE(lower_dentry->d_inode);
if (!lower_inode) /* We want to add because we couldn't find in lower */ return d_splice_alias(NULL, dentry);
inode = __ecryptfs_get_inode(lower_inode, dentry->d_sb); if (IS_ERR(inode)) { printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n", __func__, PTR_ERR(inode)); return ERR_CAST(inode); } if (S_ISREG(inode->i_mode)) { rc = ecryptfs_i_size_read(dentry, inode); if (rc) { make_bad_inode(inode); return ERR_PTR(rc); } }
if (inode_state_read_once(inode) & I_NEW) unlock_new_inode(inode); return d_splice_alias(inode, dentry);}
/** * ecryptfs_lookup * @ecryptfs_dir_inode: The eCryptfs directory inode * @ecryptfs_dentry: The eCryptfs dentry that we are looking up * @flags: lookup flags * * Find a file on disk. If the file does not exist, then we'll add it to the * dentry cache and continue on to read it from the disk. */static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode, struct dentry *ecryptfs_dentry, unsigned int flags){ char *encrypted_and_encoded_name = NULL; struct ecryptfs_mount_crypt_stat *mount_crypt_stat; struct dentry *lower_dir_dentry, *lower_dentry; struct qstr qname = QSTR_INIT(ecryptfs_dentry->d_name.name, ecryptfs_dentry->d_name.len); struct dentry *res; int rc = 0;
lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
mount_crypt_stat = &ecryptfs_superblock_to_private( ecryptfs_dentry->d_sb)->mount_crypt_stat; if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) { size_t len = qname.len; rc = ecryptfs_encrypt_and_encode_filename( &encrypted_and_encoded_name, &len, mount_crypt_stat, qname.name, len); if (rc) { printk(KERN_ERR "%s: Error attempting to encrypt and encode " "filename; rc = [%d]\n", __func__, rc); return ERR_PTR(rc); } qname.name = encrypted_and_encoded_name; qname.len = len; }
lower_dentry = lookup_noperm_unlocked(&qname, lower_dir_dentry); if (IS_ERR(lower_dentry)) { ecryptfs_printk(KERN_DEBUG, "%s: lookup_noperm() returned " "[%ld] on lower_dentry = [%s]\n", __func__, PTR_ERR(lower_dentry), qname.name); res = ERR_CAST(lower_dentry); } else { res = ecryptfs_lookup_interpose(ecryptfs_dentry, lower_dentry); } kfree(encrypted_and_encoded_name); return res;}
static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry){ struct dentry *lower_old_dentry; struct dentry *lower_new_dentry; struct inode *lower_dir; u64 file_size_save; int rc;
file_size_save = i_size_read(d_inode(old_dentry)); lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); lower_new_dentry = ecryptfs_start_creating_dentry(new_dentry); if (IS_ERR(lower_new_dentry)) return PTR_ERR(lower_new_dentry); lower_dir = lower_new_dentry->d_parent->d_inode; rc = vfs_link(lower_old_dentry, &nop_mnt_idmap, lower_dir, lower_new_dentry, NULL); if (rc || d_really_is_negative(lower_new_dentry)) goto out_lock; rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb); if (rc) goto out_lock; fsstack_copy_attr_times(dir, lower_dir); fsstack_copy_inode_size(dir, lower_dir); set_nlink(d_inode(old_dentry), ecryptfs_inode_to_lower(d_inode(old_dentry))->i_nlink); i_size_write(d_inode(new_dentry), file_size_save);out_lock: end_creating(lower_new_dentry); return rc;}
static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry){ return ecryptfs_do_unlink(dir, dentry, d_inode(dentry));}
static int ecryptfs_symlink(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, const char *symname){ int rc; struct dentry *lower_dentry; struct inode *lower_dir; char *encoded_symname; size_t encoded_symlen; struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
lower_dentry = ecryptfs_start_creating_dentry(dentry); if (IS_ERR(lower_dentry)) return PTR_ERR(lower_dentry); lower_dir = lower_dentry->d_parent->d_inode;
mount_crypt_stat = &ecryptfs_superblock_to_private( dir->i_sb)->mount_crypt_stat; rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname, &encoded_symlen, mount_crypt_stat, symname, strlen(symname)); if (rc) goto out_lock; rc = vfs_symlink(&nop_mnt_idmap, lower_dir, lower_dentry, encoded_symname, NULL); kfree(encoded_symname); if (rc || d_really_is_negative(lower_dentry)) goto out_lock; rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); if (rc) goto out_lock; fsstack_copy_attr_times(dir, lower_dir); fsstack_copy_inode_size(dir, lower_dir);out_lock: end_creating(lower_dentry); if (d_really_is_negative(dentry)) d_drop(dentry); return rc;}
static struct dentry *ecryptfs_mkdir(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, umode_t mode){ int rc; struct dentry *lower_dentry; struct dentry *lower_dir_dentry; struct inode *lower_dir;
lower_dentry = ecryptfs_start_creating_dentry(dentry); if (IS_ERR(lower_dentry)) return lower_dentry; lower_dir_dentry = dget(lower_dentry->d_parent); lower_dir = lower_dir_dentry->d_inode; lower_dentry = vfs_mkdir(&nop_mnt_idmap, lower_dir, lower_dentry, mode, NULL); rc = PTR_ERR(lower_dentry); if (IS_ERR(lower_dentry)) goto out; rc = 0; if (d_unhashed(lower_dentry)) goto out; rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); if (rc) goto out; fsstack_copy_attr_times(dir, lower_dir); fsstack_copy_inode_size(dir, lower_dir); set_nlink(dir, lower_dir->i_nlink);out: dput(lower_dir_dentry); end_creating(lower_dentry); if (d_really_is_negative(dentry)) d_drop(dentry); return ERR_PTR(rc);}
static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry){ struct dentry *lower_dentry; struct inode *lower_dir; int rc;
lower_dentry = ecryptfs_start_removing_dentry(dentry); if (IS_ERR(lower_dentry)) return PTR_ERR(lower_dentry); lower_dir = lower_dentry->d_parent->d_inode;
rc = vfs_rmdir(&nop_mnt_idmap, lower_dir, lower_dentry, NULL); if (!rc) { clear_nlink(d_inode(dentry)); fsstack_copy_attr_times(dir, lower_dir); set_nlink(dir, lower_dir->i_nlink); } end_removing(lower_dentry); if (!rc) d_drop(dentry); return rc;}
static intecryptfs_mknod(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev){ int rc; struct dentry *lower_dentry; struct inode *lower_dir;
lower_dentry = ecryptfs_start_creating_dentry(dentry); if (IS_ERR(lower_dentry)) return PTR_ERR(lower_dentry); lower_dir = lower_dentry->d_parent->d_inode;
rc = vfs_mknod(&nop_mnt_idmap, lower_dir, lower_dentry, mode, dev, NULL); if (rc || d_really_is_negative(lower_dentry)) goto out; rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); if (rc) goto out; fsstack_copy_attr_times(dir, lower_dir); fsstack_copy_inode_size(dir, lower_dir);out: end_creating(lower_dentry); if (d_really_is_negative(dentry)) d_drop(dentry); return rc;}
static intecryptfs_rename(struct mnt_idmap *idmap, struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags){ int rc; struct dentry *lower_old_dentry; struct dentry *lower_new_dentry; struct dentry *lower_old_dir_dentry; struct dentry *lower_new_dir_dentry; struct inode *target_inode; struct renamedata rd = {};
if (flags) return -EINVAL;
lower_old_dir_dentry = ecryptfs_dentry_to_lower(old_dentry->d_parent); lower_new_dir_dentry = ecryptfs_dentry_to_lower(new_dentry->d_parent);
lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
target_inode = d_inode(new_dentry);
rd.mnt_idmap = &nop_mnt_idmap; rd.old_parent = lower_old_dir_dentry; rd.new_parent = lower_new_dir_dentry; rc = start_renaming_two_dentries(&rd, lower_old_dentry, lower_new_dentry); if (rc) return rc;
rc = vfs_rename(&rd); if (rc) goto out_lock; if (target_inode) fsstack_copy_attr_all(target_inode, ecryptfs_inode_to_lower(target_inode)); fsstack_copy_attr_all(new_dir, d_inode(lower_new_dir_dentry)); if (new_dir != old_dir) fsstack_copy_attr_all(old_dir, d_inode(lower_old_dir_dentry));out_lock: end_renaming(&rd); return rc;}
static char *ecryptfs_readlink_lower(struct dentry *dentry, size_t *bufsiz){ DEFINE_DELAYED_CALL(done); struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); const char *link; char *buf; int rc;
link = vfs_get_link(lower_dentry, &done); if (IS_ERR(link)) return ERR_CAST(link);
rc = ecryptfs_decode_and_decrypt_filename(&buf, bufsiz, dentry->d_sb, link, strlen(link)); do_delayed_call(&done); if (rc) return ERR_PTR(rc);
return buf;}
static const char *ecryptfs_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *done){ size_t len; char *buf;
if (!dentry) return ERR_PTR(-ECHILD);
buf = ecryptfs_readlink_lower(dentry, &len); if (IS_ERR(buf)) return buf; fsstack_copy_attr_atime(d_inode(dentry), d_inode(ecryptfs_dentry_to_lower(dentry))); buf[len] = '\0'; set_delayed_call(done, kfree_link, buf); return buf;}
static void ecryptfs_iattr_to_lower(struct iattr *lower_ia, const struct iattr *ia){ memcpy(lower_ia, ia, sizeof(*lower_ia)); if (ia->ia_valid & ATTR_FILE) lower_ia->ia_file = ecryptfs_file_to_lower(ia->ia_file); /* * If the mode change is for clearing setuid/setgid bits, allow the lower * file system to interpret this in its own way. */ if (lower_ia->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) lower_ia->ia_valid &= ~ATTR_MODE;}
/** * upper_size_to_lower_size * @crypt_stat: Crypt_stat associated with file * @upper_size: Size of the upper file * * Calculate the required size of the lower file based on the * specified size of the upper file. This calculation is based on the * number of headers in the underlying file and the extent size. * * Returns Calculated size of the lower file. */static loff_tupper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, loff_t upper_size){ loff_t lower_size;
lower_size = ecryptfs_lower_header_size(crypt_stat); if (upper_size != 0) { loff_t num_extents;
num_extents = upper_size >> crypt_stat->extent_shift; if (upper_size & ~crypt_stat->extent_mask) num_extents++; lower_size += (num_extents * crypt_stat->extent_size); } return lower_size;}
/** * __ecryptfs_truncate * @dentry: The ecryptfs layer dentry * @ia: Address of the ecryptfs inode's attributes * * Handle truncations modifying the size of the file. Note that the file sizes * are interpolated. When expanding, we are simply writing strings of 0's out. * When truncating, we truncate the upper inode and update the lower_ia * according to the page index interpolations. * * Returns zero on success; non-zero otherwise */static int __ecryptfs_truncate(struct dentry *dentry, const struct iattr *ia){ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); struct inode *inode = d_inode(dentry); struct ecryptfs_crypt_stat *crypt_stat; loff_t i_size = i_size_read(inode); loff_t lower_size_before_truncate; loff_t lower_size_after_truncate; struct iattr lower_ia; size_t num_zeros; int rc;
ecryptfs_iattr_to_lower(&lower_ia, ia);
if (unlikely((ia->ia_size == i_size))) return 0;
crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; lower_size_before_truncate = upper_size_to_lower_size(crypt_stat, i_size); lower_size_after_truncate = upper_size_to_lower_size(crypt_stat, ia->ia_size); if (lower_size_after_truncate > lower_size_before_truncate) { /* * The eCryptfs inode and the new *lower* size are mixed here * because we may not have the lower i_mutex held and/or it may * not be appropriate to call inode_newsize_ok() with inodes * from other filesystems. */ rc = inode_newsize_ok(inode, lower_size_after_truncate); if (rc) return rc; }
rc = ecryptfs_get_lower_file(dentry, inode); if (rc) return rc;
if (ia->ia_size > i_size) { char zero[] = { 0x00 };
/* * Write a single 0 at the last position of the file; this * triggers code that will fill in 0's throughout the * intermediate portion of the previous end of the file and the * new end of the file. */ rc = ecryptfs_write(inode, zero, ia->ia_size - 1, 1); goto out; }
if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { truncate_setsize(inode, ia->ia_size); lower_ia.ia_size = ia->ia_size; goto set_size; }
/* * We're chopping off all the pages down to the page in which * ia->ia_size is located. Fill in the end of that page from * (ia->ia_size & ~PAGE_MASK) to PAGE_SIZE with zeros. */ num_zeros = PAGE_SIZE - (ia->ia_size & ~PAGE_MASK); if (num_zeros) { rc = ecryptfs_write(inode, page_address(ZERO_PAGE(0)), ia->ia_size, num_zeros); if (rc) { pr_err("Error attempting to zero out the remainder of the end page on reducing truncate; rc = [%d]\n", rc); goto out; } } truncate_setsize(inode, ia->ia_size); rc = ecryptfs_write_inode_size_to_metadata(inode); if (rc) { pr_err("Problem with ecryptfs_write_inode_size_to_metadata; rc = [%d]\n", rc); goto out; }
/* * We are reducing the size of the ecryptfs file, and need to know if we * need to reduce the size of the lower file. */ if (lower_size_after_truncate >= lower_size_before_truncate) goto out;
lower_ia.ia_size = lower_size_after_truncate;set_size: lower_ia.ia_valid |= ATTR_SIZE; inode_lock(d_inode(lower_dentry)); rc = notify_change(&nop_mnt_idmap, lower_dentry, &lower_ia, NULL); inode_unlock(d_inode(lower_dentry));out: ecryptfs_put_lower_file(inode); return rc;}
/** * ecryptfs_truncate * @dentry: The ecryptfs layer dentry * @new_length: The length to expand the file to * * Simple function that handles the truncation of an eCryptfs inode and * its corresponding lower inode. * * Returns zero on success; non-zero otherwise */int ecryptfs_truncate(struct dentry *dentry, loff_t new_length){ const struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length, };
return __ecryptfs_truncate(dentry, &ia);}
static intecryptfs_permission(struct mnt_idmap *idmap, struct inode *inode, int mask){ return inode_permission(&nop_mnt_idmap, ecryptfs_inode_to_lower(inode), mask);}
/** * ecryptfs_setattr * @idmap: idmap of the target mount * @dentry: dentry handle to the inode to modify * @ia: Structure with flags of what to change and values * * Updates the metadata of an inode. If the update is to the size * i.e. truncation, then ecryptfs_truncate will handle the size modification * of both the ecryptfs inode and the lower inode. * * All other metadata changes will be passed right to the lower filesystem, * and we will just update our inode to look like the lower. */static int ecryptfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *ia){ struct inode *inode = d_inode(dentry); struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); struct inode *lower_inode = ecryptfs_inode_to_lower(inode); struct ecryptfs_crypt_stat *crypt_stat; int rc;
crypt_stat = &ecryptfs_inode_to_private(d_inode(dentry))->crypt_stat; if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) ecryptfs_init_crypt_stat(crypt_stat);
mutex_lock(&crypt_stat->cs_mutex); if (d_is_dir(dentry)) crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); else if (d_is_reg(dentry) && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED) || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) { struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
mount_crypt_stat = &ecryptfs_superblock_to_private( dentry->d_sb)->mount_crypt_stat; rc = ecryptfs_get_lower_file(dentry, inode); if (rc) { mutex_unlock(&crypt_stat->cs_mutex); goto out; } rc = ecryptfs_read_metadata(dentry); ecryptfs_put_lower_file(inode); if (rc) { if (!(mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) { rc = -EIO; printk(KERN_WARNING "Either the lower file " "is not in a valid eCryptfs format, " "or the key could not be retrieved. " "Plaintext passthrough mode is not " "enabled; returning -EIO\n"); mutex_unlock(&crypt_stat->cs_mutex); goto out; } rc = 0; crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED | ECRYPTFS_ENCRYPTED); } } mutex_unlock(&crypt_stat->cs_mutex);
rc = setattr_prepare(&nop_mnt_idmap, dentry, ia); if (rc) goto out;
if (ia->ia_valid & ATTR_SIZE) { rc = __ecryptfs_truncate(dentry, ia); } else { struct iattr lower_ia;
ecryptfs_iattr_to_lower(&lower_ia, ia);
inode_lock(d_inode(lower_dentry)); rc = notify_change(&nop_mnt_idmap, lower_dentry, &lower_ia, NULL); inode_unlock(d_inode(lower_dentry)); }out: fsstack_copy_attr_all(inode, lower_inode); return rc;}
static int ecryptfs_getattr_link(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags){ struct dentry *dentry = path->dentry; struct ecryptfs_mount_crypt_stat *mount_crypt_stat; int rc = 0;
mount_crypt_stat = &ecryptfs_superblock_to_private( dentry->d_sb)->mount_crypt_stat; generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(dentry), stat); if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) { char *target; size_t targetsiz;
target = ecryptfs_readlink_lower(dentry, &targetsiz); if (!IS_ERR(target)) { kfree(target); stat->size = targetsiz; } else { rc = PTR_ERR(target); } } return rc;}
static int ecryptfs_getattr(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags){ struct dentry *dentry = path->dentry; struct kstat lower_stat; struct path lower_path = ecryptfs_lower_path(dentry); int rc;
rc = vfs_getattr_nosec(&lower_path, &lower_stat, request_mask, flags); if (!rc) { fsstack_copy_attr_all(d_inode(dentry), ecryptfs_inode_to_lower(d_inode(dentry))); generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(dentry), stat); stat->blocks = lower_stat.blocks; } return rc;}
intecryptfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name, const void *value, size_t size, int flags){ int rc; struct dentry *lower_dentry; struct inode *lower_inode;
lower_dentry = ecryptfs_dentry_to_lower(dentry); lower_inode = d_inode(lower_dentry); if (!(lower_inode->i_opflags & IOP_XATTR)) { rc = -EOPNOTSUPP; goto out; } inode_lock(lower_inode); rc = __vfs_setxattr_locked(&nop_mnt_idmap, lower_dentry, name, value, size, flags, NULL); inode_unlock(lower_inode); if (!rc && inode) fsstack_copy_attr_all(inode, lower_inode);out: return rc;}
ssize_tecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode, const char *name, void *value, size_t size){ int rc;
if (!(lower_inode->i_opflags & IOP_XATTR)) { rc = -EOPNOTSUPP; goto out; } inode_lock(lower_inode); rc = __vfs_getxattr(lower_dentry, lower_inode, name, value, size); inode_unlock(lower_inode);out: return rc;}
static ssize_tecryptfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name, void *value, size_t size){ return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), ecryptfs_inode_to_lower(inode), name, value, size);}
static ssize_tecryptfs_listxattr(struct dentry *dentry, char *list, size_t size){ int rc = 0; struct dentry *lower_dentry;
lower_dentry = ecryptfs_dentry_to_lower(dentry); if (!d_inode(lower_dentry)->i_op->listxattr) { rc = -EOPNOTSUPP; goto out; } inode_lock(d_inode(lower_dentry)); rc = d_inode(lower_dentry)->i_op->listxattr(lower_dentry, list, size); inode_unlock(d_inode(lower_dentry));out: return rc;}
static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode, const char *name){ int rc; struct dentry *lower_dentry; struct inode *lower_inode;
lower_dentry = ecryptfs_dentry_to_lower(dentry); lower_inode = ecryptfs_inode_to_lower(inode); if (!(lower_inode->i_opflags & IOP_XATTR)) { rc = -EOPNOTSUPP; goto out; } inode_lock(lower_inode); rc = __vfs_removexattr(&nop_mnt_idmap, lower_dentry, name); inode_unlock(lower_inode);out: return rc;}
static int ecryptfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa){ return vfs_fileattr_get(ecryptfs_dentry_to_lower(dentry), fa);}
static int ecryptfs_fileattr_set(struct mnt_idmap *idmap, struct dentry *dentry, struct file_kattr *fa){ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); int rc;
rc = vfs_fileattr_set(&nop_mnt_idmap, lower_dentry, fa); fsstack_copy_attr_all(d_inode(dentry), d_inode(lower_dentry));
return rc;}
static struct posix_acl *ecryptfs_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, int type){ return vfs_get_acl(idmap, ecryptfs_dentry_to_lower(dentry), posix_acl_xattr_name(type));}
static int ecryptfs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, struct posix_acl *acl, int type){ int rc; struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); struct inode *lower_inode = d_inode(lower_dentry);
rc = vfs_set_acl(&nop_mnt_idmap, lower_dentry, posix_acl_xattr_name(type), acl); if (!rc) fsstack_copy_attr_all(d_inode(dentry), lower_inode); return rc;}
const struct inode_operations ecryptfs_symlink_iops = { .get_link = ecryptfs_get_link, .permission = ecryptfs_permission, .setattr = ecryptfs_setattr, .getattr = ecryptfs_getattr_link, .listxattr = ecryptfs_listxattr,};
const struct inode_operations ecryptfs_dir_iops = { .create = ecryptfs_create, .lookup = ecryptfs_lookup, .link = ecryptfs_link, .unlink = ecryptfs_unlink, .symlink = ecryptfs_symlink, .mkdir = ecryptfs_mkdir, .rmdir = ecryptfs_rmdir, .mknod = ecryptfs_mknod, .rename = ecryptfs_rename, .permission = ecryptfs_permission, .setattr = ecryptfs_setattr, .listxattr = ecryptfs_listxattr, .fileattr_get = ecryptfs_fileattr_get, .fileattr_set = ecryptfs_fileattr_set, .get_acl = ecryptfs_get_acl, .set_acl = ecryptfs_set_acl,};
const struct inode_operations ecryptfs_main_iops = { .permission = ecryptfs_permission, .setattr = ecryptfs_setattr, .getattr = ecryptfs_getattr, .listxattr = ecryptfs_listxattr, .fileattr_get = ecryptfs_fileattr_get, .fileattr_set = ecryptfs_fileattr_set, .get_acl = ecryptfs_get_acl, .set_acl = ecryptfs_set_acl,};
static int ecryptfs_xattr_get(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size){ return ecryptfs_getxattr(dentry, inode, name, buffer, size);}
static int ecryptfs_xattr_set(const struct xattr_handler *handler, struct mnt_idmap *idmap, struct dentry *dentry, struct inode *inode, const char *name, const void *value, size_t size, int flags){ if (value) return ecryptfs_setxattr(dentry, inode, name, value, size, flags); else { BUG_ON(flags != XATTR_REPLACE); return ecryptfs_removexattr(dentry, inode, name); }}
static const struct xattr_handler ecryptfs_xattr_handler = { .prefix = "", /* match anything */ .get = ecryptfs_xattr_get, .set = ecryptfs_xattr_set,};
const struct xattr_handler * const ecryptfs_xattr_handlers[] = { &ecryptfs_xattr_handler, NULL};