/* * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU General Public License version 2. */ #include <linux/sched.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/completion.h> #include <linux/buffer_head.h> #include <linux/posix_acl.h> #include <linux/posix_acl_xattr.h> #include <linux/gfs2_ondisk.h> #include "gfs2.h" #include "incore.h" #include "acl.h" #include "eaops.h" #include "eattr.h" #include "glock.h" #include "inode.h" #include "meta_io.h" #include "trans.h" #include "util.h" #define ACL_ACCESS 1 #define ACL_DEFAULT 0 int gfs2_acl_validate_set(struct gfs2_inode *ip, int access, struct gfs2_ea_request *er, int *remove, mode_t *mode) { struct posix_acl *acl; int error; error = gfs2_acl_validate_remove(ip, access); if (error) return error; if (!er->er_data) return -EINVAL; acl = posix_acl_from_xattr(er->er_data, er->er_data_len); if (IS_ERR(acl)) return PTR_ERR(acl); if (!acl) { *remove = 1; return 0; } error = posix_acl_valid(acl); if (error) goto out; if (access) { error = posix_acl_equiv_mode(acl, mode); if (!error) *remove = 1; else if (error > 0) error = 0; } out: posix_acl_release(acl); return error; } int gfs2_acl_validate_remove(struct gfs2_inode *ip, int access) { if (!GFS2_SB(&ip->i_inode)->sd_args.ar_posix_acl) return -EOPNOTSUPP; if (!is_owner_or_cap(&ip->i_inode)) return -EPERM; if (S_ISLNK(ip->i_inode.i_mode)) return -EOPNOTSUPP; if (!access && !S_ISDIR(ip->i_inode.i_mode)) return -EACCES; return 0; } static int acl_get(struct gfs2_inode *ip, int access, struct posix_acl **acl, struct gfs2_ea_location *el, char **data, unsigned int *len) { struct gfs2_ea_request er; struct gfs2_ea_location el_this; int error; if (!ip->i_eattr) return 0; memset(&er, 0, sizeof(struct gfs2_ea_request)); if (access) { er.er_name = GFS2_POSIX_ACL_ACCESS; er.er_name_len = GFS2_POSIX_ACL_ACCESS_LEN; } else { er.er_name = GFS2_POSIX_ACL_DEFAULT; er.er_name_len = GFS2_POSIX_ACL_DEFAULT_LEN; } er.er_type = GFS2_EATYPE_SYS; if (!el) el = &el_this; error = gfs2_ea_find(ip, &er, el); if (error) return error; if (!el->el_ea) return 0; if (!GFS2_EA_DATA_LEN(el->el_ea)) goto out; er.er_data_len = GFS2_EA_DATA_LEN(el->el_ea); er.er_data = kmalloc(er.er_data_len, GFP_NOFS); error = -ENOMEM; if (!er.er_data) goto out; error = gfs2_ea_get_copy(ip, el, er.er_data); if (error) goto out_kfree; if (acl) { *acl = posix_acl_from_xattr(er.er_data, er.er_data_len); if (IS_ERR(*acl)) error = PTR_ERR(*acl); } out_kfree: if (error || !data) kfree(er.er_data); else { *data = er.er_data; *len = er.er_data_len; } out: if (error || el == &el_this) brelse(el->el_bh); return error; } /** * gfs2_check_acl - Check an ACL to see if we're allowed to do something * @inode: the file we want to do something to * @mask: what we want to do * * Returns: errno */ int gfs2_check_acl(struct inode *inode, int mask) { struct posix_acl *acl = NULL; int error; error = acl_get(GFS2_I(inode), ACL_ACCESS, &acl, NULL, NULL, NULL); if (error) return error; if (acl) { error = posix_acl_permission(inode, acl, mask); posix_acl_release(acl); return error; } return -EAGAIN; } static int munge_mode(struct gfs2_inode *ip, mode_t mode) { struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); struct buffer_head *dibh; int error; error = gfs2_trans_begin(sdp, RES_DINODE, 0); if (error) return error; error = gfs2_meta_inode_buffer(ip, &dibh); if (!error) { gfs2_assert_withdraw(sdp, (ip->i_inode.i_mode & S_IFMT) == (mode & S_IFMT)); ip->i_inode.i_mode = mode; gfs2_trans_add_bh(ip->i_gl, dibh, 1); gfs2_dinode_out(ip, dibh->b_data); brelse(dibh); } gfs2_trans_end(sdp); return 0; } int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip) { struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode); struct posix_acl *acl = NULL, *clone; struct gfs2_ea_request er; mode_t mode = ip->i_inode.i_mode; int error; if (!sdp->sd_args.ar_posix_acl) return 0; if (S_ISLNK(ip->i_inode.i_mode)) return 0; memset(&er, 0, sizeof(struct gfs2_ea_request)); er.er_type = GFS2_EATYPE_SYS; error = acl_get(dip, ACL_DEFAULT, &acl, NULL, &er.er_data, &er.er_data_len); if (error) return error; if (!acl) { mode &= ~current_umask(); if (mode != ip->i_inode.i_mode) error = munge_mode(ip, mode); return error; } clone = posix_acl_clone(acl, GFP_NOFS); error = -ENOMEM; if (!clone) goto out; posix_acl_release(acl); acl = clone; if (S_ISDIR(ip->i_inode.i_mode)) { er.er_name = GFS2_POSIX_ACL_DEFAULT; er.er_name_len = GFS2_POSIX_ACL_DEFAULT_LEN; error = gfs2_system_eaops.eo_set(ip, &er); if (error) goto out; } error = posix_acl_create_masq(acl, &mode); if (error < 0) goto out; if (error > 0) { er.er_name = GFS2_POSIX_ACL_ACCESS; er.er_name_len = GFS2_POSIX_ACL_ACCESS_LEN; posix_acl_to_xattr(acl, er.er_data, er.er_data_len); er.er_mode = mode; er.er_flags = GFS2_ERF_MODE; error = gfs2_system_eaops.eo_set(ip, &er); if (error) goto out; } else munge_mode(ip, mode); out: posix_acl_release(acl); kfree(er.er_data); return error; } int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr) { struct posix_acl *acl = NULL, *clone; struct gfs2_ea_location el; char *data; unsigned int len; int error; error = acl_get(ip, ACL_ACCESS, &acl, &el, &data, &len); if (error) return error; if (!acl) return gfs2_setattr_simple(ip, attr); clone = posix_acl_clone(acl, GFP_NOFS); error = -ENOMEM; if (!clone) goto out; posix_acl_release(acl); acl = clone; error = posix_acl_chmod_masq(acl, attr->ia_mode); if (!error) { posix_acl_to_xattr(acl, data, len); error = gfs2_ea_acl_chmod(ip, &el, attr, data); } out: posix_acl_release(acl); brelse(el.el_bh); kfree(data); return error; }