--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+#include "bcachefs.h"
+
+#include "acl.h"
+#include "xattr.h"
+
+#include <linux/posix_acl.h>
+
+static const char * const acl_types[] = {
+ [ACL_USER_OBJ] = "user_obj",
+ [ACL_USER] = "user",
+ [ACL_GROUP_OBJ] = "group_obj",
+ [ACL_GROUP] = "group",
+ [ACL_MASK] = "mask",
+ [ACL_OTHER] = "other",
+ NULL,
+};
+
+void bch2_acl_to_text(struct printbuf *out, const void *value, size_t size)
+{
+ const void *p, *end = value + size;
+
+ if (!value ||
+ size < sizeof(bch_acl_header) ||
+ ((bch_acl_header *)value)->a_version != cpu_to_le32(BCH_ACL_VERSION))
+ return;
+
+ p = value + sizeof(bch_acl_header);
+ while (p < end) {
+ const bch_acl_entry *in = p;
+ unsigned tag = le16_to_cpu(in->e_tag);
+
+ prt_str(out, acl_types[tag]);
+
+ switch (tag) {
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ p += sizeof(bch_acl_entry_short);
+ break;
+ case ACL_USER:
+ prt_printf(out, " uid %u", le32_to_cpu(in->e_id));
+ p += sizeof(bch_acl_entry);
+ break;
+ case ACL_GROUP:
+ prt_printf(out, " gid %u", le32_to_cpu(in->e_id));
+ p += sizeof(bch_acl_entry);
+ break;
+ }
+
+ prt_printf(out, " %o", le16_to_cpu(in->e_perm));
+
+ if (p != end)
+ prt_char(out, ' ');
+ }
+}
+
+#ifdef CONFIG_BCACHEFS_POSIX_ACL
+
+#include "fs.h"
+
+#include <linux/fs.h>
+#include <linux/posix_acl_xattr.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+static inline size_t bch2_acl_size(unsigned nr_short, unsigned nr_long)
+{
+ return sizeof(bch_acl_header) +
+ sizeof(bch_acl_entry_short) * nr_short +
+ sizeof(bch_acl_entry) * nr_long;
+}
+
+static inline int acl_to_xattr_type(int type)
+{
+ switch (type) {
+ case ACL_TYPE_ACCESS:
+ return KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS;
+ case ACL_TYPE_DEFAULT:
+ return KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT;
+ default:
+ BUG();
+ }
+}
+
+/*
+ * Convert from filesystem to in-memory representation.
+ */
+static struct posix_acl *bch2_acl_from_disk(struct btree_trans *trans,
+ const void *value, size_t size)
+{
+ const void *p, *end = value + size;
+ struct posix_acl *acl;
+ struct posix_acl_entry *out;
+ unsigned count = 0;
+ int ret;
+
+ if (!value)
+ return NULL;
+ if (size < sizeof(bch_acl_header))
+ goto invalid;
+ if (((bch_acl_header *)value)->a_version !=
+ cpu_to_le32(BCH_ACL_VERSION))
+ goto invalid;
+
+ p = value + sizeof(bch_acl_header);
+ while (p < end) {
+ const bch_acl_entry *entry = p;
+
+ if (p + sizeof(bch_acl_entry_short) > end)
+ goto invalid;
+
+ switch (le16_to_cpu(entry->e_tag)) {
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ p += sizeof(bch_acl_entry_short);
+ break;
+ case ACL_USER:
+ case ACL_GROUP:
+ p += sizeof(bch_acl_entry);
+ break;
+ default:
+ goto invalid;
+ }
+
+ count++;
+ }
+
+ if (p > end)
+ goto invalid;
+
+ if (!count)
+ return NULL;
+
+ acl = allocate_dropping_locks(trans, ret,
+ posix_acl_alloc(count, _gfp));
+ if (!acl)
+ return ERR_PTR(-ENOMEM);
+ if (ret) {
+ kfree(acl);
+ return ERR_PTR(ret);
+ }
+
+ out = acl->a_entries;
+
+ p = value + sizeof(bch_acl_header);
+ while (p < end) {
+ const bch_acl_entry *in = p;
+
+ out->e_tag = le16_to_cpu(in->e_tag);
+ out->e_perm = le16_to_cpu(in->e_perm);
+
+ switch (out->e_tag) {
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ p += sizeof(bch_acl_entry_short);
+ break;
+ case ACL_USER:
+ out->e_uid = make_kuid(&init_user_ns,
+ le32_to_cpu(in->e_id));
+ p += sizeof(bch_acl_entry);
+ break;
+ case ACL_GROUP:
+ out->e_gid = make_kgid(&init_user_ns,
+ le32_to_cpu(in->e_id));
+ p += sizeof(bch_acl_entry);
+ break;
+ }
+
+ out++;
+ }
+
+ BUG_ON(out != acl->a_entries + acl->a_count);
+
+ return acl;
+invalid:
+ pr_err("invalid acl entry");
+ return ERR_PTR(-EINVAL);
+}
+
+#define acl_for_each_entry(acl, acl_e) \
+ for (acl_e = acl->a_entries; \
+ acl_e < acl->a_entries + acl->a_count; \
+ acl_e++)
+
+/*
+ * Convert from in-memory to filesystem representation.
+ */
+static struct bkey_i_xattr *
+bch2_acl_to_xattr(struct btree_trans *trans,
+ const struct posix_acl *acl,
+ int type)
+{
+ struct bkey_i_xattr *xattr;
+ bch_acl_header *acl_header;
+ const struct posix_acl_entry *acl_e;
+ void *outptr;
+ unsigned nr_short = 0, nr_long = 0, acl_len, u64s;
+
+ acl_for_each_entry(acl, acl_e) {
+ switch (acl_e->e_tag) {
+ case ACL_USER:
+ case ACL_GROUP:
+ nr_long++;
+ break;
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ nr_short++;
+ break;
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+ }
+
+ acl_len = bch2_acl_size(nr_short, nr_long);
+ u64s = BKEY_U64s + xattr_val_u64s(0, acl_len);
+
+ if (u64s > U8_MAX)
+ return ERR_PTR(-E2BIG);
+
+ xattr = bch2_trans_kmalloc(trans, u64s * sizeof(u64));
+ if (IS_ERR(xattr))
+ return xattr;
+
+ bkey_xattr_init(&xattr->k_i);
+ xattr->k.u64s = u64s;
+ xattr->v.x_type = acl_to_xattr_type(type);
+ xattr->v.x_name_len = 0;
+ xattr->v.x_val_len = cpu_to_le16(acl_len);
+
+ acl_header = xattr_val(&xattr->v);
+ acl_header->a_version = cpu_to_le32(BCH_ACL_VERSION);
+
+ outptr = (void *) acl_header + sizeof(*acl_header);
+
+ acl_for_each_entry(acl, acl_e) {
+ bch_acl_entry *entry = outptr;
+
+ entry->e_tag = cpu_to_le16(acl_e->e_tag);
+ entry->e_perm = cpu_to_le16(acl_e->e_perm);
+ switch (acl_e->e_tag) {
+ case ACL_USER:
+ entry->e_id = cpu_to_le32(
+ from_kuid(&init_user_ns, acl_e->e_uid));
+ outptr += sizeof(bch_acl_entry);
+ break;
+ case ACL_GROUP:
+ entry->e_id = cpu_to_le32(
+ from_kgid(&init_user_ns, acl_e->e_gid));
+ outptr += sizeof(bch_acl_entry);
+ break;
+
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ outptr += sizeof(bch_acl_entry_short);
+ break;
+ }
+ }
+
+ BUG_ON(outptr != xattr_val(&xattr->v) + acl_len);
+
+ return xattr;
+}
+
+struct posix_acl *bch2_get_acl(struct mnt_idmap *idmap,
+ struct dentry *dentry, int type)
+{
+ struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
+ struct bch_fs *c = inode->v.i_sb->s_fs_info;
+ struct bch_hash_info hash = bch2_hash_info_init(c, &inode->ei_inode);
+ struct xattr_search_key search = X_SEARCH(acl_to_xattr_type(type), "", 0);
+ struct btree_trans *trans = bch2_trans_get(c);
+ struct btree_iter iter = { NULL };
+ struct bkey_s_c_xattr xattr;
+ struct posix_acl *acl = NULL;
+ struct bkey_s_c k;
+ int ret;
+retry:
+ bch2_trans_begin(trans);
+
+ ret = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,
+ &hash, inode_inum(inode), &search, 0);
+ if (ret) {
+ if (!bch2_err_matches(ret, ENOENT))
+ acl = ERR_PTR(ret);
+ goto out;
+ }
+
+ k = bch2_btree_iter_peek_slot(&iter);
+ ret = bkey_err(k);
+ if (ret) {
+ acl = ERR_PTR(ret);
+ goto out;
+ }
+
+ xattr = bkey_s_c_to_xattr(k);
+ acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),
+ le16_to_cpu(xattr.v->x_val_len));
+
+ if (!IS_ERR(acl))
+ set_cached_acl(&inode->v, type, acl);
+out:
+ if (bch2_err_matches(PTR_ERR_OR_ZERO(acl), BCH_ERR_transaction_restart))
+ goto retry;
+
+ bch2_trans_iter_exit(trans, &iter);
+ bch2_trans_put(trans);
+ return acl;
+}
+
+int bch2_set_acl_trans(struct btree_trans *trans, subvol_inum inum,
+ struct bch_inode_unpacked *inode_u,
+ struct posix_acl *acl, int type)
+{
+ struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode_u);
+ int ret;
+
+ if (type == ACL_TYPE_DEFAULT &&
+ !S_ISDIR(inode_u->bi_mode))
+ return acl ? -EACCES : 0;
+
+ if (acl) {
+ struct bkey_i_xattr *xattr =
+ bch2_acl_to_xattr(trans, acl, type);
+ if (IS_ERR(xattr))
+ return PTR_ERR(xattr);
+
+ ret = bch2_hash_set(trans, bch2_xattr_hash_desc, &hash_info,
+ inum, &xattr->k_i, 0);
+ } else {
+ struct xattr_search_key search =
+ X_SEARCH(acl_to_xattr_type(type), "", 0);
+
+ ret = bch2_hash_delete(trans, bch2_xattr_hash_desc, &hash_info,
+ inum, &search);
+ }
+
+ return bch2_err_matches(ret, ENOENT) ? 0 : ret;
+}
+
+int bch2_set_acl(struct mnt_idmap *idmap,
+ struct dentry *dentry,
+ struct posix_acl *_acl, int type)
+{
+ struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
+ struct bch_fs *c = inode->v.i_sb->s_fs_info;
+ struct btree_trans *trans = bch2_trans_get(c);
+ struct btree_iter inode_iter = { NULL };
+ struct bch_inode_unpacked inode_u;
+ struct posix_acl *acl;
+ umode_t mode;
+ int ret;
+
+ mutex_lock(&inode->ei_update_lock);
+retry:
+ bch2_trans_begin(trans);
+ acl = _acl;
+
+ ret = bch2_subvol_is_ro_trans(trans, inode->ei_subvol) ?:
+ bch2_inode_peek(trans, &inode_iter, &inode_u, inode_inum(inode),
+ BTREE_ITER_INTENT);
+ if (ret)
+ goto btree_err;
+
+ mode = inode_u.bi_mode;
+
+ if (type == ACL_TYPE_ACCESS) {
+ ret = posix_acl_update_mode(idmap, &inode->v, &mode, &acl);
+ if (ret)
+ goto btree_err;
+ }
+
+ ret = bch2_set_acl_trans(trans, inode_inum(inode), &inode_u, acl, type);
+ if (ret)
+ goto btree_err;
+
+ inode_u.bi_ctime = bch2_current_time(c);
+ inode_u.bi_mode = mode;
+
+ ret = bch2_inode_write(trans, &inode_iter, &inode_u) ?:
+ bch2_trans_commit(trans, NULL, NULL, 0);
+btree_err:
+ bch2_trans_iter_exit(trans, &inode_iter);
+
+ if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+ goto retry;
+ if (unlikely(ret))
+ goto err;
+
+ bch2_inode_update_after_write(trans, inode, &inode_u,
+ ATTR_CTIME|ATTR_MODE);
+
+ set_cached_acl(&inode->v, type, acl);
+err:
+ mutex_unlock(&inode->ei_update_lock);
+ bch2_trans_put(trans);
+
+ return ret;
+}
+
+int bch2_acl_chmod(struct btree_trans *trans, subvol_inum inum,
+ struct bch_inode_unpacked *inode,
+ umode_t mode,
+ struct posix_acl **new_acl)
+{
+ struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode);
+ struct xattr_search_key search = X_SEARCH(KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS, "", 0);
+ struct btree_iter iter;
+ struct bkey_s_c_xattr xattr;
+ struct bkey_i_xattr *new;
+ struct posix_acl *acl = NULL;
+ struct bkey_s_c k;
+ int ret;
+
+ ret = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,
+ &hash_info, inum, &search, BTREE_ITER_INTENT);
+ if (ret)
+ return bch2_err_matches(ret, ENOENT) ? 0 : ret;
+
+ k = bch2_btree_iter_peek_slot(&iter);
+ ret = bkey_err(k);
+ if (ret)
+ goto err;
+ xattr = bkey_s_c_to_xattr(k);
+
+ acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),
+ le16_to_cpu(xattr.v->x_val_len));
+ ret = PTR_ERR_OR_ZERO(acl);
+ if (IS_ERR_OR_NULL(acl))
+ goto err;
+
+ ret = allocate_dropping_locks_errcode(trans,
+ __posix_acl_chmod(&acl, _gfp, mode));
+ if (ret)
+ goto err;
+
+ new = bch2_acl_to_xattr(trans, acl, ACL_TYPE_ACCESS);
+ if (IS_ERR(new)) {
+ ret = PTR_ERR(new);
+ goto err;
+ }
+
+ new->k.p = iter.pos;
+ ret = bch2_trans_update(trans, &iter, &new->k_i, 0);
+ *new_acl = acl;
+ acl = NULL;
+err:
+ bch2_trans_iter_exit(trans, &iter);
+ if (!IS_ERR_OR_NULL(acl))
+ kfree(acl);
+ return ret;
+}
+
+#endif /* CONFIG_BCACHEFS_POSIX_ACL */
projects / bcachefs-tools-debian / blobdiff