Add futimens and utimensat system calls.

The core kernel part is patch file utimes.2008.4.diff from
pluknet@FreeBSD.org. I updated the code for API changes, added the manual
page and added compatibility code for old kernels. There is also audit and
Capsicum support.

A new UTIME_* constant might allow setting birthtimes in future.

Differential Revision:	https://reviews.freebsd.org/D1426
Submitted by:	pluknet (partially)
Reviewed by:	delphij, pluknet, rwatson
Relnotes:	yes

9 files changed, 196 insertions, 6 deletions

diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c
index ffea283..a72612b 100644
--- a/sys/compat/freebsd32/freebsd32_misc.c
+++ b/sys/compat/freebsd32/freebsd32_misc.c
@@ -1300,6 +1300,49 @@ freebsd32_futimesat(struct thread *td, struct freebsd32_futimesat_args *uap)
 }
 
 int
+freebsd32_futimens(struct thread *td, struct freebsd32_futimens_args *uap)
+{
+	struct timespec32 ts32[2];
+	struct timespec ts[2], *tsp;
+	int error;
+
+	if (uap->times != NULL) {
+		error = copyin(uap->times, ts32, sizeof(ts32));
+		if (error)
+			return (error);
+		CP(ts32[0], ts[0], tv_sec);
+		CP(ts32[0], ts[0], tv_nsec);
+		CP(ts32[1], ts[1], tv_sec);
+		CP(ts32[1], ts[1], tv_nsec);
+		tsp = ts;
+	} else
+		tsp = NULL;
+	return (kern_futimens(td, uap->fd, tsp, UIO_SYSSPACE));
+}
+
+int
+freebsd32_utimensat(struct thread *td, struct freebsd32_utimensat_args *uap)
+{
+	struct timespec32 ts32[2];
+	struct timespec ts[2], *tsp;
+	int error;
+
+	if (uap->times != NULL) {
+		error = copyin(uap->times, ts32, sizeof(ts32));
+		if (error)
+			return (error);
+		CP(ts32[0], ts[0], tv_sec);
+		CP(ts32[0], ts[0], tv_nsec);
+		CP(ts32[1], ts[1], tv_sec);
+		CP(ts32[1], ts[1], tv_nsec);
+		tsp = ts;
+	} else
+		tsp = NULL;
+	return (kern_utimensat(td, uap->fd, uap->path, UIO_USERSPACE,
+	    tsp, UIO_SYSSPACE, uap->flag));
+}
+
+int
 freebsd32_adjtime(struct thread *td, struct freebsd32_adjtime_args *uap)
 {
 	struct timeval32 tv32;
diff --git a/sys/compat/freebsd32/syscalls.master b/sys/compat/freebsd32/syscalls.master
index ce655bc..91d1727 100644
--- a/sys/compat/freebsd32/syscalls.master
+++ b/sys/compat/freebsd32/syscalls.master
@@ -1069,3 +1069,8 @@
 545	AUE_POLL	STD	{ int freebsd32_ppoll(struct pollfd *fds, \
 				    u_int nfds, const struct timespec32 *ts, \
 				    const sigset_t *set); }
+546	AUE_FUTIMES	STD	{ int freebsd32_futimens(int fd, \
+				    struct timespec *times); }
+547	AUE_FUTIMESAT	STD	{ int freebsd32_utimensat(int fd, \
+				    char *path, \
+				    struct timespec *times, int flag); }
diff --git a/sys/kern/capabilities.conf b/sys/kern/capabilities.conf
index f7a46ae..d0ea97c 100644
--- a/sys/kern/capabilities.conf
+++ b/sys/kern/capabilities.conf
@@ -220,8 +220,9 @@ fsync
 ftruncate
 
 ##
-## Allow futimes(2), subject to capability rights.
+## Allow futimens(2) and futimes(2), subject to capability rights.
 ##
+futimens
 futimes
 
 ##
@@ -453,6 +454,7 @@ readlinkat
 renameat
 symlinkat
 unlinkat
+utimensat
 
 ##
 ## Allow entry into open(2). This system call will fail, since access to the
diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index 089896b..09d38d4 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -983,5 +983,10 @@
 545	AUE_POLL	STD	{ int ppoll(struct pollfd *fds, u_int nfds, \
 				    const struct timespec *ts, \
 				    const sigset_t *set); }
+546	AUE_FUTIMES	STD	{ int futimens(int fd, \
+				    struct timespec *times); }
+547	AUE_FUTIMESAT	STD	{ int utimensat(int fd, \
+				    char *path, \
+				    struct timespec *times, int flag); }
 ; Please copy any additions and changes to the following compatability tables:
 ; sys/compat/freebsd32/syscalls.master
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index 3105c2f..0f24819 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -95,10 +95,12 @@ SDT_PROBE_DEFINE2(vfs, , stat, mode, "char *", "int");
 SDT_PROBE_DEFINE2(vfs, , stat, reg, "char *", "int");
 
 static int chroot_refuse_vdir_fds(struct filedesc *fdp);
-static int getutimes(const struct timeval *, enum uio_seg, struct timespec *);
 static int kern_chflagsat(struct thread *td, int fd, const char *path,
     enum uio_seg pathseg, u_long flags, int atflag);
 static int setfflags(struct thread *td, struct vnode *, u_long);
+static int getutimes(const struct timeval *, enum uio_seg, struct timespec *);
+static int getutimens(const struct timespec *, enum uio_seg,
+    struct timespec *, int *);
 static int setutimes(struct thread *td, struct vnode *,
     const struct timespec *, int, int);
 static int vn_access(struct vnode *vp, int user_flags, struct ucred *cred,
@@ -3007,7 +3009,53 @@ getutimes(usrtvp, tvpseg, tsp)
 }
 
 /*
- * Common implementation code for utimes(), lutimes(), and futimes().
+ * Common implementation code for futimens(), utimensat().
+ */
+#define	UTIMENS_NULL	0x1
+#define	UTIMENS_EXIT	0x2
+static int
+getutimens(const struct timespec *usrtsp, enum uio_seg tspseg,
+    struct timespec *tsp, int *retflags)
+{
+	struct timespec tsnow;
+	int error;
+
+	vfs_timestamp(&tsnow);
+	*retflags = 0;
+	if (usrtsp == NULL) {
+		tsp[0] = tsnow;
+		tsp[1] = tsnow;
+		*retflags |= UTIMENS_NULL;
+		return (0);
+	}
+	if (tspseg == UIO_SYSSPACE) {
+		tsp[0] = usrtsp[0];
+		tsp[1] = usrtsp[1];
+	} else if ((error = copyin(usrtsp, tsp, sizeof(*tsp) * 2)) != 0)
+		return (error);
+	if (tsp[0].tv_nsec == UTIME_OMIT && tsp[1].tv_nsec == UTIME_OMIT)
+		*retflags |= UTIMENS_EXIT;
+	if (tsp[0].tv_nsec == UTIME_NOW && tsp[1].tv_nsec == UTIME_NOW)
+		*retflags |= UTIMENS_NULL;
+	if (tsp[0].tv_nsec == UTIME_OMIT)
+		tsp[0].tv_sec = VNOVAL;
+	else if (tsp[0].tv_nsec == UTIME_NOW)
+		tsp[0] = tsnow;
+	else if (tsp[0].tv_nsec < 0 || tsp[0].tv_nsec >= 1000000000L)
+		return (EINVAL);
+	if (tsp[1].tv_nsec == UTIME_OMIT)
+		tsp[1].tv_sec = VNOVAL;
+	else if (tsp[1].tv_nsec == UTIME_NOW)
+		tsp[1] = tsnow;
+	else if (tsp[1].tv_nsec < 0 || tsp[1].tv_nsec >= 1000000000L)
+		return (EINVAL);
+
+	return (0);
+}
+
+/*
+ * Common implementation code for utimes(), lutimes(), futimes(), futimens(),
+ * and utimensat().
  */
 static int
 setutimes(td, vp, ts, numtimes, nullflag)
@@ -3196,6 +3244,80 @@ kern_futimes(struct thread *td, int fd, struct timeval *tptr,
 	return (error);
 }
 
+int
+sys_futimens(struct thread *td, struct futimens_args *uap)
+{
+
+	return (kern_futimens(td, uap->fd, uap->times, UIO_USERSPACE));
+}
+
+int
+kern_futimens(struct thread *td, int fd, struct timespec *tptr,
+    enum uio_seg tptrseg)
+{
+	struct timespec ts[2];
+	struct file *fp;
+	cap_rights_t rights;
+	int error, flags;
+
+	AUDIT_ARG_FD(fd);
+	error = getutimens(tptr, tptrseg, ts, &flags);
+	if (error != 0)
+		return (error);
+	if (flags & UTIMENS_EXIT)
+		return (0);
+	error = getvnode(td->td_proc->p_fd, fd,
+	    cap_rights_init(&rights, CAP_FUTIMES), &fp);
+	if (error != 0)
+		return (error);
+#ifdef AUDIT
+	vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
+	AUDIT_ARG_VNODE1(fp->f_vnode);
+	VOP_UNLOCK(fp->f_vnode, 0);
+#endif
+	error = setutimes(td, fp->f_vnode, ts, 2, flags & UTIMENS_NULL);
+	fdrop(fp, td);
+	return (error);
+}
+
+int
+sys_utimensat(struct thread *td, struct utimensat_args *uap)
+{
+
+	return (kern_utimensat(td, uap->fd, uap->path, UIO_USERSPACE,
+	    uap->times, UIO_USERSPACE, uap->flag));
+}
+
+int
+kern_utimensat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
+    struct timespec *tptr, enum uio_seg tptrseg, int flag)
+{
+	struct nameidata nd;
+	struct timespec ts[2];
+	int error, flags;
+
+	if (flag & ~AT_SYMLINK_NOFOLLOW)
+		return (EINVAL);
+
+	if ((error = getutimens(tptr, tptrseg, ts, &flags)) != 0)
+		return (error);
+	NDINIT_AT(&nd, LOOKUP, ((flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW :
+	    FOLLOW) | AUDITVNODE1, pathseg, path, fd, td);
+	if ((error = namei(&nd)) != 0)
+		return (error);
+	/*
+	 * We are allowed to call namei() regardless of 2xUTIME_OMIT.
+	 * POSIX states:
+	 * "If both tv_nsec fields are UTIME_OMIT... EACCESS may be detected."
+	 * "Search permission is denied by a component of the path prefix."
+	 */
+	NDFREE(&nd, NDF_ONLY_PNBUF);
+	if ((flags & UTIMENS_EXIT) == 0)
+		error = setutimes(td, nd.ni_vp, ts, 2, flags & UTIMENS_NULL);
+	vrele(nd.ni_vp);
+	return (error);
+}
+
 /*
  * Truncate a file given its path name.
  */
diff --git a/sys/sys/capsicum.h b/sys/sys/capsicum.h
index de113c6..8502a96 100644
--- a/sys/sys/capsicum.h
+++ b/sys/sys/capsicum.h
@@ -146,9 +146,9 @@
 #define	CAP_FSTATAT		(CAP_FSTAT | CAP_LOOKUP)
 /* Allows for fstatfs(2). */
 #define	CAP_FSTATFS		CAPRIGHT(0, 0x0000000000100000ULL)
-/* Allows for futimes(2). */
+/* Allows for futimens(2) and futimes(2). */
 #define	CAP_FUTIMES		CAPRIGHT(0, 0x0000000000200000ULL)
-/* Allows for futimes(2) and futimesat(2). */
+/* Allows for futimens(2), futimes(2), futimesat(2) and utimensat(2). */
 #define	CAP_FUTIMESAT		(CAP_FUTIMES | CAP_LOOKUP)
 /* Allows for linkat(2) and renameat(2) (destination directory descriptor). */
 #define	CAP_LINKAT		(CAP_LOOKUP | 0x0000000000400000ULL)
diff --git a/sys/sys/param.h b/sys/sys/param.h
index bf59b0b..eea93c9 100644
--- a/sys/sys/param.h
+++ b/sys/sys/param.h
@@ -58,7 +58,7 @@
  *		in the range 5 to 9.
  */
 #undef __FreeBSD_version
-#define __FreeBSD_version 1100055	/* Master, propagated to newvers */
+#define __FreeBSD_version 1100056	/* Master, propagated to newvers */
 
 /*
  * __FreeBSD_kernel__ indicates that this system uses the kernel of FreeBSD,
diff --git a/sys/sys/stat.h b/sys/sys/stat.h
index 13dea2d..7a4370d 100644
--- a/sys/sys/stat.h
+++ b/sys/sys/stat.h
@@ -307,6 +307,11 @@ struct nstat {
 
 #endif /* __BSD_VISIBLE */
 
+#if __POSIX_VISIBLE >= 200809
+#define	UTIME_NOW	-1
+#define	UTIME_OMIT	-2
+#endif
+
 #ifndef _KERNEL
 __BEGIN_DECLS
 #if __BSD_VISIBLE
@@ -322,6 +327,9 @@ int	fchmod(int, mode_t);
 #endif
 #if __POSIX_VISIBLE >= 200809
 int	fchmodat(int, const char *, mode_t, int);
+int	futimens(int fd, const struct timespec times[2]);
+int	utimensat(int fd, const char *path, const struct timespec times[2],
+		int flag);
 #endif
 int	fstat(int, struct stat *);
 #if __BSD_VISIBLE
diff --git a/sys/sys/syscallsubr.h b/sys/sys/syscallsubr.h
index f4131a4..cb6d4e3 100644
--- a/sys/sys/syscallsubr.h
+++ b/sys/sys/syscallsubr.h
@@ -99,6 +99,8 @@ int	kern_fstatfs(struct thread *td, int fd, struct statfs *buf);
 int	kern_ftruncate(struct thread *td, int fd, off_t length);
 int	kern_futimes(struct thread *td, int fd, struct timeval *tptr,
 	    enum uio_seg tptrseg);
+int	kern_futimens(struct thread *td, int fd, struct timespec *tptr,
+	    enum uio_seg tptrseg);
 int	kern_getdirentries(struct thread *td, int fd, char *buf, u_int count,
 	    long *basep, ssize_t *residp, enum uio_seg bufseg);
 int	kern_getfsstat(struct thread *td, struct statfs **buf, size_t bufsize,
@@ -220,6 +222,9 @@ int	kern_unlinkat(struct thread *td, int fd, char *path,
 	    enum uio_seg pathseg, ino_t oldinum);
 int	kern_utimesat(struct thread *td, int fd, char *path,
 	    enum uio_seg pathseg, struct timeval *tptr, enum uio_seg tptrseg);
+int	kern_utimensat(struct thread *td, int fd, char *path,
+	    enum uio_seg pathseg, struct timespec *tptr, enum uio_seg tptrseg,
+	    int follow);
 int	kern_wait(struct thread *td, pid_t pid, int *status, int options,
 	    struct rusage *rup);
 int	kern_wait6(struct thread *td, enum idtype idtype, id_t id, int *status,