2 * (The copyright below applies to ufs_access())
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40 * @(#)ufs_vnops.c 8.27 (Berkeley) 5/27/95
41 * $DragonFly: src/sys/kern/vfs_helper.c,v 1.5 2008/05/25 18:34:46 dillon Exp $
44 #include "opt_quota.h"
45 #include "opt_suiddir.h"
47 #include <sys/param.h>
48 #include <sys/systm.h>
50 #include <sys/kernel.h>
51 #include <sys/fcntl.h>
53 #include <sys/mount.h>
54 #include <sys/unistd.h>
55 #include <sys/vnode.h>
56 #include <sys/file.h> /* XXX */
64 * Provide standard UNIX semanics for VOP_ACCESS, but without the quota
65 * code. This procedure was basically pulled out of UFS.
68 vop_helper_access(struct vop_access_args *ap, uid_t ino_uid, gid_t ino_gid,
69 mode_t ino_mode, u_int32_t ino_flags)
71 struct vnode *vp = ap->a_vp;
72 struct ucred *cred = ap->a_cred;
73 mode_t mask, mode = ap->a_mode;
78 * Disallow write attempts on read-only filesystems;
79 * unless the file is a socket, fifo, or a block or
80 * character device resident on the filesystem.
88 if (vp->v_mount->mnt_flag & MNT_RDONLY)
96 /* If immutable bit set, nobody gets to write it. */
97 if ((mode & VWRITE) && (ino_flags & IMMUTABLE))
100 /* Otherwise, user id 0 always gets access. */
101 if (cred->cr_uid == 0)
106 /* Otherwise, check the owner. */
107 if (cred->cr_uid == ino_uid) {
114 return ((ino_mode & mask) == mask ? 0 : EACCES);
117 /* Otherwise, check the groups. */
118 for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++)
119 if (ino_gid == *gp) {
126 return ((ino_mode & mask) == mask ? 0 : EACCES);
129 /* Otherwise, check everyone else. */
136 return ((ino_mode & mask) == mask ? 0 : EACCES);
140 vop_helper_setattr_flags(u_int32_t *ino_flags, u_int32_t vaflags,
141 uid_t uid, struct ucred *cred)
146 * If uid doesn't match only a privileged user can change the flags
148 if (cred->cr_uid != uid &&
149 (error = priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0))) {
152 if (cred->cr_uid == 0 &&
153 (!jailed(cred)|| jail_chflags_allowed)) {
154 if ((*ino_flags & (SF_NOUNLINK|SF_IMMUTABLE|SF_APPEND)) &&
157 *ino_flags = vaflags;
159 if (*ino_flags & (SF_NOUNLINK|SF_IMMUTABLE|SF_APPEND) ||
160 (vaflags & UF_SETTABLE) != vaflags)
162 *ino_flags &= SF_SETTABLE;
163 *ino_flags |= vaflags & UF_SETTABLE;
169 * This helper function may be used by VFSs to implement UNIX initial
170 * ownership semantics when creating new objects inside directories.
173 vop_helper_create_uid(struct mount *mp, mode_t dmode, uid_t duid,
174 struct ucred *cred, mode_t *modep)
177 if ((mp->mnt_flag & MNT_SUIDDIR) && (dmode & S_ISUID) &&
178 duid != cred->cr_uid && duid) {
183 return(cred->cr_uid);
187 * This helper may be used by VFSs to implement unix chmod semantics.
189 * XXX TEMPORARY chmod override for VCHR devices. Allow the device to
190 * override the uid if the uid is not root. This is used
191 * by pty's to set the owner for the related tty.
193 * XXX REMOVE THE OVERRIDE WHEN DEVFS IS MERGED.
196 vop_helper_chmod(struct vnode *vp, mode_t new_mode, struct ucred *cred,
197 uid_t cur_uid, gid_t cur_gid, mode_t *cur_modep)
201 if (cred->cr_uid != cur_uid) {
202 error = priv_check_cred(cred, PRIV_VFS_CHMOD, 0);
207 if (vp->v_type != VDIR && (*cur_modep & S_ISTXT))
209 if (!groupmember(cur_gid, cred) && (*cur_modep & S_ISGID))
212 *cur_modep &= ~ALLPERMS;
213 *cur_modep |= new_mode & ALLPERMS;
218 * This helper may be used by VFSs to implement unix chown semantics.
221 vop_helper_chown(struct vnode *vp, uid_t new_uid, gid_t new_gid,
223 uid_t *cur_uidp, gid_t *cur_gidp, mode_t *cur_modep)
229 if (new_uid == (uid_t)VNOVAL)
231 if (new_gid == (gid_t)VNOVAL)
235 * If we don't own the file, are trying to change the owner
236 * of the file, or are not a member of the target group,
237 * the caller must be privileged or the call fails.
239 if ((cred->cr_uid != *cur_uidp || new_uid != *cur_uidp ||
240 (new_gid != *cur_gidp && !(cred->cr_gid == new_gid ||
241 groupmember(new_gid, cred)))) &&
242 (error = priv_check_cred(cred, PRIV_VFS_CHOWN, 0))) {
253 * DragonFly clears both SUID and SGID if either the owner or
254 * group is changed and root isn't doing it. If root is doing
255 * it we do not clear SUID/SGID.
257 if (cred->cr_uid != 0 && (ouid != new_uid || ogid != new_gid))
258 *cur_modep &= ~(S_ISUID | S_ISGID);