Sweep kernel replacing suser(9) calls with priv(9) calls, assigning

specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>

2 files changed, 51 insertions, 36 deletions

diff --git a/sys/fs/msdosfs/msdosfs_vfsops.c b/sys/fs/msdosfs/msdosfs_vfsops.c
index c0963cb..b6d81f4 100644
--- a/sys/fs/msdosfs/msdosfs_vfsops.c
+++ b/sys/fs/msdosfs/msdosfs_vfsops.c
@@ -52,6 +52,7 @@
 #include <sys/systm.h>
 #include <sys/conf.h>
 #include <sys/namei.h>
+#include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/kernel.h>
 #include <sys/vnode.h>
@@ -293,17 +294,17 @@ msdosfs_mount(struct mount *mp, struct thread *td)
 			 * If upgrade to read-write by non-root, then verify
 			 * that user has necessary permissions on the device.
 			 */
-			if (suser(td)) {
-				devvp = pmp->pm_devvp;
-				vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
-				error = VOP_ACCESS(devvp, VREAD | VWRITE,
-						   td->td_ucred, td);
-				if (error) {
-					VOP_UNLOCK(devvp, 0, td);
-					return (error);
-				}
+			devvp = pmp->pm_devvp;
+			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
+			error = VOP_ACCESS(devvp, VREAD | VWRITE,
+			   td->td_ucred, td);
+			if (error)
+				error = priv_check(td, PRIV_VFS_MOUNT_PERM);
+			if (error) {
 				VOP_UNLOCK(devvp, 0, td);
+				return (error);
 			}
+			VOP_UNLOCK(devvp, 0, td);
 			DROP_GIANT();
 			g_topology_lock();
 			error = g_access(pmp->pm_cp, 0, 1, 0);
@@ -353,15 +354,15 @@ msdosfs_mount(struct mount *mp, struct thread *td)
 	 * If mount by non-root, then verify that user has necessary
 	 * permissions on the device.
 	 */
-	if (suser(td)) {
-		accessmode = VREAD;
-		if ((mp->mnt_flag & MNT_RDONLY) == 0)
-			accessmode |= VWRITE;
-		error = VOP_ACCESS(devvp, accessmode, td->td_ucred, td);
-		if (error) {
-			vput(devvp);
-			return (error);
-		}
+	accessmode = VREAD;
+	if ((mp->mnt_flag & MNT_RDONLY) == 0)
+		accessmode |= VWRITE;
+	error = VOP_ACCESS(devvp, accessmode, td->td_ucred, td);
+	if (error)
+		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
+	if (error) {
+		vput(devvp);
+		return (error);
 	}
 	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
 		error = mountmsdosfs(devvp, mp, td);
diff --git a/sys/fs/msdosfs/msdosfs_vnops.c b/sys/fs/msdosfs/msdosfs_vnops.c
index e7a64e7..ae17f89 100644
--- a/sys/fs/msdosfs/msdosfs_vnops.c
+++ b/sys/fs/msdosfs/msdosfs_vnops.c
@@ -59,6 +59,7 @@
 #include <sys/conf.h>
 #include <sys/clock.h>
 #include <sys/buf.h>
+#include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/mount.h>
 #include <sys/unistd.h>
@@ -404,9 +405,12 @@ msdosfs_setattr(ap)
 	if (vap->va_flags != VNOVAL) {
 		if (vp->v_mount->mnt_flag & MNT_RDONLY)
 			return (EROFS);
-		if (cred->cr_uid != pmp->pm_uid &&
-		    (error = suser_cred(cred, SUSER_ALLOWJAIL)))
-			return (error);
+		if (cred->cr_uid != pmp->pm_uid) {
+			error = priv_check_cred(cred, PRIV_VFS_ADMIN,
+			    SUSER_ALLOWJAIL);
+			if (error)
+				return (error);
+		}
 		/*
 		 * We are very inconsistent about handling unsupported
 		 * attributes.  We ignored the access time and the
@@ -419,9 +423,11 @@ msdosfs_setattr(ap)
 		 * set ATTR_ARCHIVE for directories `cp -pr' from a more
 		 * sensible filesystem attempts it a lot.
 		 */
-		if (suser_cred(cred, SUSER_ALLOWJAIL)) {
-			if (vap->va_flags & SF_SETTABLE)
-				return EPERM;
+		if (vap->va_flags & SF_SETTABLE) {
+			error = priv_check_cred(cred, PRIV_VFS_SYSFLAGS,
+			    SUSER_ALLOWJAIL);
+			if (error)
+				return (error);
 		}
 		if (vap->va_flags & ~SF_ARCHIVED)
 			return EOPNOTSUPP;
@@ -444,10 +450,13 @@ msdosfs_setattr(ap)
 		gid = vap->va_gid;
 		if (gid == (gid_t)VNOVAL)
 			gid = pmp->pm_gid;
-		if ((cred->cr_uid != pmp->pm_uid || uid != pmp->pm_uid ||
-		    (gid != pmp->pm_gid && !groupmember(gid, cred))) &&
-		    (error = suser_cred(cred, SUSER_ALLOWJAIL)))
-			return error;
+		if (cred->cr_uid != pmp->pm_uid || uid != pmp->pm_uid ||
+		    (gid != pmp->pm_gid && !groupmember(gid, cred))) {
+			error = priv_check_cred(cred, PRIV_VFS_CHOWN,
+			    SUSER_ALLOWJAIL);
+			if (error)
+				return (error);
+		}
 		if (uid != pmp->pm_uid || gid != pmp->pm_gid)
 			return EINVAL;
 	}
@@ -477,11 +486,13 @@ msdosfs_setattr(ap)
 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
 		if (vp->v_mount->mnt_flag & MNT_RDONLY)
 			return (EROFS);
-		if (cred->cr_uid != pmp->pm_uid &&
-		    (error = suser_cred(cred, SUSER_ALLOWJAIL)) &&
-		    ((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
-		    (error = VOP_ACCESS(ap->a_vp, VWRITE, cred, ap->a_td))))
-			return (error);
+		if (vap->va_vaflags & VA_UTIMES_NULL) {
+			error = VOP_ACCESS(vp, VADMIN, cred, ap->a_td); 
+			if (error)
+				error = VOP_ACCESS(vp, VWRITE, cred,
+				    ap->a_td);
+		} else
+			error = VOP_ACCESS(vp, VADMIN, cred, ap->a_td);
 		if (vp->v_type != VDIR) {
 			if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95) == 0 &&
 			    vap->va_atime.tv_sec != VNOVAL) {
@@ -506,9 +517,12 @@ msdosfs_setattr(ap)
 	if (vap->va_mode != (mode_t)VNOVAL) {
 		if (vp->v_mount->mnt_flag & MNT_RDONLY)
 			return (EROFS);
-		if (cred->cr_uid != pmp->pm_uid &&
-		    (error = suser_cred(cred, SUSER_ALLOWJAIL)))
-			return (error);
+		if (cred->cr_uid != pmp->pm_uid) {
+			error = priv_check_cred(cred, PRIV_VFS_ADMIN,
+			    SUSER_ALLOWJAIL);
+			if (error)
+				return (error);
+		}
 		if (vp->v_type != VDIR) {
 			/* We ignore the read and execute bits. */
 			if (vap->va_mode & VWRITE)