diff --git a/toolbox/Android.mk b/toolbox/Android.mk
index 4fff9f5..682ce59 100644
--- a/toolbox/Android.mk
+++ b/toolbox/Android.mk
@@ -80,15 +80,23 @@
 	grep
 
 LOCAL_SRC_FILES := \
+	cp/cp.c \
+	cp/utils.c \
 	dynarray.c \
-	toolbox.c \
+	grep/fastgrep.c \
+	grep/file.c \
+	grep/grep.c \
+	grep/queue.c \
+	grep/util.c \
 	$(patsubst %,%.c,$(TOOLS)) \
-	cp/cp.c cp/utils.c \
-	grep/grep.c grep/fastgrep.c grep/file.c grep/queue.c grep/util.c
+	toolbox.c \
+	uid_from_user.c \
 
 LOCAL_C_INCLUDES := bionic/libc/bionic
 
-LOCAL_CFLAGS += -Wno-unused-parameter
+LOCAL_CFLAGS += \
+    -Wno-unused-parameter \
+    -DSUPPORT_DOT \
 
 LOCAL_SHARED_LIBRARIES := \
 	libcutils \
diff --git a/toolbox/chown.c b/toolbox/chown.c
index 92efee6..6ac2233 100644
--- a/toolbox/chown.c
+++ b/toolbox/chown.c
@@ -1,73 +1,302 @@
+/*	$NetBSD: chown.c,v 1.8 2012/10/24 01:12:51 enami Exp $	*/
+
+/*
+ * Copyright (c) 1988, 1993, 1994, 2003
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#ifndef lint
+__COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994, 2003\
+ The Regents of the University of California.  All rights reserved.");
+#endif /* not lint */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)chown.c	8.8 (Berkeley) 4/4/94";
+#else
+__RCSID("$NetBSD: chown.c,v 1.8 2012/10/24 01:12:51 enami Exp $");
+#endif
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <ctype.h>
+#include <dirent.h>
+#include <err.h>
+#include <errno.h>
+#include <locale.h>
+#include <fts.h>
+#include <grp.h>
+#include <pwd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <sys/types.h>
-#include <dirent.h>
-#include <errno.h>
-#include <pwd.h>
-#include <grp.h>
-
 #include <unistd.h>
-#include <time.h>
+#include <getopt.h>
 
-int chown_main(int argc, char **argv)
+static void	a_gid(const char *);
+static void	a_uid(const char *);
+static id_t	id(const char *, const char *);
+__dead static void	usage(void);
+
+static uid_t uid;
+static gid_t gid;
+static int ischown;
+static const char *myname;
+
+struct option chown_longopts[] = {
+	{ "reference",		required_argument,	0,
+						1 },
+	{ NULL,			0,			0,
+						0 },
+};
+
+int
+chown_main(int argc, char **argv)
 {
-    int i;
+	FTS *ftsp;
+	FTSENT *p;
+	int Hflag, Lflag, Rflag, ch, fflag, fts_options, hflag, rval, vflag;
+	char *cp, *reference;
+	int (*change_owner)(const char *, uid_t, gid_t);
 
-    if (argc < 3) {
-        fprintf(stderr, "Usage: chown <USER>[:GROUP] <FILE1> [FILE2] ...\n");
-        return 10;
-    }
+	setprogname(*argv);
 
-    // Copy argv[1] to 'user' so we can truncate it at the period
-    // if a group id specified.
-    char user[32];
-    char *group = NULL;
-    strncpy(user, argv[1], sizeof(user));
-    if ((group = strchr(user, ':')) != NULL) {
-        *group++ = '\0';
-    } else if ((group = strchr(user, '.')) != NULL) {
-        *group++ = '\0';
-    }
+	(void)setlocale(LC_ALL, "");
 
-    // Lookup uid (and gid if specified)
-    struct passwd *pw;
-    struct group *grp = NULL;
-    uid_t uid;
-    gid_t gid = -1; // passing -1 to chown preserves current group
+	myname = getprogname();
+	ischown = (myname[2] == 'o');
+	reference = NULL;
 
-    pw = getpwnam(user);
-    if (pw != NULL) {
-        uid = pw->pw_uid;
-    } else {
-        char* endptr;
-        uid = (int) strtoul(user, &endptr, 0);
-        if (endptr == user) {  // no conversion
-          fprintf(stderr, "No such user '%s'\n", user);
-          return 10;
-        }
-    }
+	Hflag = Lflag = Rflag = fflag = hflag = vflag = 0;
+	while ((ch = getopt_long(argc, argv, "HLPRfhv",
+	    chown_longopts, NULL)) != -1)
+		switch (ch) {
+		case 1:
+			reference = optarg;
+			break;
+		case 'H':
+			Hflag = 1;
+			Lflag = 0;
+			break;
+		case 'L':
+			Lflag = 1;
+			Hflag = 0;
+			break;
+		case 'P':
+			Hflag = Lflag = 0;
+			break;
+		case 'R':
+			Rflag = 1;
+			break;
+		case 'f':
+			fflag = 1;
+			break;
+		case 'h':
+			/*
+			 * In System V the -h option causes chown/chgrp to
+			 * change the owner/group of the symbolic link.
+			 * 4.4BSD's symbolic links didn't have owners/groups,
+			 * so it was an undocumented noop.
+			 * In NetBSD 1.3, lchown(2) is introduced.
+			 */
+			hflag = 1;
+			break;
+		case 'v':
+			vflag = 1;
+			break;
+		case '?':
+		default:
+			usage();
+		}
+	argv += optind;
+	argc -= optind;
 
-    if (group != NULL) {
-        grp = getgrnam(group);
-        if (grp != NULL) {
-            gid = grp->gr_gid;
-        } else {
-            char* endptr;
-            gid = (int) strtoul(group, &endptr, 0);
-            if (endptr == group) {  // no conversion
-                fprintf(stderr, "No such group '%s'\n", group);
-                return 10;
-            }
-        }
-    }
+	if (argc == 0 || (argc == 1 && reference == NULL))
+		usage();
 
-    for (i = 2; i < argc; i++) {
-        if (chown(argv[i], uid, gid) < 0) {
-            fprintf(stderr, "Unable to chown %s: %s\n", argv[i], strerror(errno));
-            return 10;
-        }
-    }
+	fts_options = FTS_PHYSICAL;
+	if (Rflag) {
+		if (Hflag)
+			fts_options |= FTS_COMFOLLOW;
+		if (Lflag) {
+			if (hflag)
+				errx(EXIT_FAILURE,
+				    "the -L and -h options "
+				    "may not be specified together.");
+			fts_options &= ~FTS_PHYSICAL;
+			fts_options |= FTS_LOGICAL;
+		}
+	} else if (!hflag)
+		fts_options |= FTS_COMFOLLOW;
 
-    return 0;
+	uid = (uid_t)-1;
+	gid = (gid_t)-1;
+	if (reference == NULL) {
+		if (ischown) {
+			if ((cp = strchr(*argv, ':')) != NULL) {
+				*cp++ = '\0';
+				a_gid(cp);
+			}
+#ifdef SUPPORT_DOT
+			else if ((cp = strrchr(*argv, '.')) != NULL) {
+				if (uid_from_user(*argv, &uid) == -1) {
+					*cp++ = '\0';
+					a_gid(cp);
+				}
+			}
+#endif
+			a_uid(*argv);
+		} else
+			a_gid(*argv);
+		argv++;
+	} else {
+		struct stat st;
+
+		if (stat(reference, &st) == -1)
+			err(EXIT_FAILURE, "Cannot stat `%s'", reference);
+		if (ischown)
+			uid = st.st_uid;
+		gid = st.st_gid;
+	}
+
+	if ((ftsp = fts_open(argv, fts_options, NULL)) == NULL)
+		err(EXIT_FAILURE, "fts_open");
+
+	for (rval = EXIT_SUCCESS; (p = fts_read(ftsp)) != NULL;) {
+		change_owner = chown;
+		switch (p->fts_info) {
+		case FTS_D:
+			if (!Rflag)		/* Change it at FTS_DP. */
+				fts_set(ftsp, p, FTS_SKIP);
+			continue;
+		case FTS_DNR:			/* Warn, chown, continue. */
+			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
+			rval = EXIT_FAILURE;
+			break;
+		case FTS_ERR:			/* Warn, continue. */
+		case FTS_NS:
+			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
+			rval = EXIT_FAILURE;
+			continue;
+		case FTS_SL:			/* Ignore unless -h. */
+			/*
+			 * All symlinks we found while doing a physical
+			 * walk end up here.
+			 */
+			if (!hflag)
+				continue;
+			/*
+			 * Note that if we follow a symlink, fts_info is
+			 * not FTS_SL but FTS_F or whatever.  And we should
+			 * use lchown only for FTS_SL and should use chown
+			 * for others.
+			 */
+			change_owner = lchown;
+			break;
+		case FTS_SLNONE:		/* Ignore. */
+			/*
+			 * The only symlinks that end up here are ones that
+			 * don't point to anything.  Note that if we are
+			 * doing a phisycal walk, we never reach here unless
+			 * we asked to follow explicitly.
+			 */
+			continue;
+		default:
+			break;
+		}
+
+		if ((*change_owner)(p->fts_accpath, uid, gid) && !fflag) {
+			warn("%s", p->fts_path);
+			rval = EXIT_FAILURE;
+		} else {
+			if (vflag)
+				printf("%s\n", p->fts_path);
+		}
+	}
+	if (errno)
+		err(EXIT_FAILURE, "fts_read");
+	exit(rval);
+	/* NOTREACHED */
+}
+
+static void
+a_gid(const char *s)
+{
+	struct group *gr;
+
+	if (*s == '\0')			/* Argument was "uid[:.]". */
+		return;
+	gr = *s == '#' ? NULL : getgrnam(s);
+	if (gr == NULL)
+		gid = id(s, "group");
+	else
+		gid = gr->gr_gid;
+	return;
+}
+
+static void
+a_uid(const char *s)
+{
+	if (*s == '\0')			/* Argument was "[:.]gid". */
+		return;
+	if (*s == '#' || uid_from_user(s, &uid) == -1) {
+		uid = id(s, "user");
+	}
+	return;
+}
+
+static id_t
+id(const char *name, const char *type)
+{
+	id_t val;
+	char *ep;
+
+	errno = 0;
+	if (*name == '#')
+		name++;
+	val = (id_t)strtoul(name, &ep, 10);
+	if (errno)
+		err(EXIT_FAILURE, "%s", name);
+	if (*ep != '\0')
+		errx(EXIT_FAILURE, "%s: invalid %s name", name, type);
+	return (val);
+}
+
+static void
+usage(void)
+{
+
+	(void)fprintf(stderr,
+	    "Usage: %s [-R [-H | -L | -P]] [-fhv] %s file ...\n"
+	    "\t%s [-R [-H | -L | -P]] [-fhv] --reference=rfile file ...\n",
+	    myname, ischown ? "owner:group|owner|:group" : "group",
+	    myname);
+	exit(EXIT_FAILURE);
 }
diff --git a/toolbox/uid_from_user.c b/toolbox/uid_from_user.c
new file mode 100644
index 0000000..d70f410
--- /dev/null
+++ b/toolbox/uid_from_user.c
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2014, The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <limits.h>
+#include <pwd.h>
+#include <stdlib.h>
+#include <sys/types.h>
+
+int uid_from_user(const char* name, uid_t* uid) {
+  struct passwd* pw = getpwnam(name);
+  if (pw != NULL) {
+    *uid = pw->pw_uid;
+    return 0;
+  }
+  // Try to parse as an integer.
+  char* end_ptr;
+  unsigned long number = strtoul(name, &end_ptr, 0);
+  if (end_ptr == name || *end_ptr != '\0' || number > INT_MAX) {
+    return -1;
+  }
+  *uid = (int) number;
+  return 0;
+}