Add generation number randomization. Newly created filesystems wil now

automatically have random generation numbers. The kenel way of handling those
also changed. Further it is advised to run fsirand on all your nfs exported
filesystems. the code is mostly copied from OpenBSD, with the randomization
chanegd to use /dev/urandom
Reviewed by:	Garrett
Obtained from: OpenBSD

3 files changed, 409 insertions, 0 deletions

diff --git a/sbin/fsirand/Makefile b/sbin/fsirand/Makefile
new file mode 100644
index 0000000..5f2446b
--- /dev/null
+++ b/sbin/fsirand/Makefile
@@ -0,0 +1,8 @@
+#	$OpenBSD: Makefile,v 1.1 1997/01/26 02:23:20 millert Exp $
+
+PROG=	fsirand
+MAN=	fsirand.8
+DPADD=	${LIBUTIL}
+LDADD=	-lutil
+
+.include <bsd.prog.mk>
diff --git a/sbin/fsirand/fsirand.8 b/sbin/fsirand/fsirand.8
new file mode 100644
index 0000000..94a02e3
--- /dev/null
+++ b/sbin/fsirand/fsirand.8
@@ -0,0 +1,109 @@
+.\" Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
+.\" 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. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by Todd C. Miller.
+.\" 4. The name of the author may not be used to endorse or promote products
+.\"    derived from this software without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED ``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 AUTHOR 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.
+.\"
+.\"	$OpenBSD: fsirand.8,v 1.6 1997/02/23 03:58:26 millert Exp $
+.\"
+.Dd January 25, 1997
+.Dt FSIRAND 8
+.Os
+.Sh NAME
+.Nm fsirand
+.Nd randomize inode generation numbers
+.Sh SYNOPSIS
+.Nm fsirand
+.Op Fl b
+.Op Fl f
+.Op Fl p
+.Ar special
+.Op Ar "special ..."
+.Sh DESCRIPTION
+The
+.Nm fsirand
+command installs random generation numbers on all the inodes for
+each filesystem specified on the command line by
+.Ar special .
+This increases the security of NFS-exported filesystems by making
+it difficult to ``guess'' filehandles.
+.Pp
+.Em Note:
+.Xr newfs 8
+now does the equivalent of
+.Nm
+itself so it is no longer necesary to
+run
+.Nm
+by hand on a new filesystem.  It is only used to
+re-randomize or report on an existing filesystem.
+.Pp
+.Nm Fsirand
+should only be used on an unmounted filesystem that
+has been checked with
+.Xr fsck 8
+or a filesystem that is mounted read-only.
+.Nm Fsirand
+may be used on the root filesystem in single-user mode
+but the system should be rebooted via ``reboot -n'' afterwards.
+.Sh OPTIONS
+.Bl -tag -width indent
+The available options are as follows:
+.It Fl b
+Use the default block size (usuallyt 512 bytes) instead
+of the value gleaned from the disklabel.
+.It Fl f
+Force
+.Nm
+to run even if the filesystem on
+.Ar special
+is not marked as clean.
+.It Fl p
+Print the current generation numbers for all inodes instead of
+generating new ones.
+.Sh CAVEATS
+Since
+.Nm
+allocates enough memory to hold all the inodes in
+a given cylinder group it is may use a large amount
+of memory for large disks with few cylinder groups.
+.Sh SEE ALSO
+.Xr fs 5 ,
+.Xr fsck 8 ,
+.Xr newfs 8 .
+.Sh HISTORY
+The
+.Nm
+command appeared in SunOS 3.x.
+.br
+This version of
+.Nm
+first appeared in
+.Bx Open
+2.1.
+.Sh AUTHOR
+.nf
+Todd C. Miller <Todd.Miller@courtesan.com>
+.fi
diff --git a/sbin/fsirand/fsirand.c b/sbin/fsirand/fsirand.c
new file mode 100644
index 0000000..4875ef5
--- /dev/null
+++ b/sbin/fsirand/fsirand.c
@@ -0,0 +1,292 @@
+/*	$OpenBSD: fsirand.c,v 1.9 1997/02/28 00:46:33 millert Exp $	*/
+
+/*
+ * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Todd C. Miller.
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``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 AUTHOR 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.
+ */
+
+#ifndef lint                                                              
+static char rcsid[] = "$OpenBSD: fsirand.c,v 1.9 1997/02/28 00:46:33 millert Exp $";
+#endif /* not lint */                                                        
+
+#include <sys/types.h>
+#include <sys/disklabel.h>
+#include <sys/ioctl.h>
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+
+#include <ufs/ffs/fs.h>
+#include <ufs/ufs/dinode.h>
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+void usage __P((int));
+int fsirand __P((char *));
+
+extern char *__progname;
+
+int printonly = 0, force = 0, ignorelabel = 0;
+
+int
+main(argc, argv)
+	int	argc;
+	char	*argv[];
+{
+	int n, ex = 0;
+	struct rlimit rl;
+
+	while ((n = getopt(argc, argv, "bfp")) != -1) {
+		switch (n) {
+		case 'b':
+			ignorelabel++;
+			break;
+		case 'p':
+			printonly++;
+			break;
+		case 'f':
+			force++;
+			break;
+		default:
+			usage(1);
+		}
+	}
+	if (argc - optind < 1)
+		usage(1);
+
+	/* Increase our data size to the max */
+	if (getrlimit(RLIMIT_DATA, &rl) == 0) {
+		rl.rlim_cur = rl.rlim_max;
+		if (setrlimit(RLIMIT_DATA, &rl) < 0)
+			warn("Can't get resource limit to max data size");
+	} else
+		warn("Can't get resource limit for data size");
+
+	for (n = optind; n < argc; n++) {
+		if (argc - optind != 1)
+			(void)puts(argv[n]);
+		ex += fsirand(argv[n]);
+		if (n < argc - 1)
+			putchar('\n');
+	}
+
+	exit(ex);
+}
+
+int
+fsirand(device)
+	char *device;
+{
+	static struct dinode *inodebuf;
+	static size_t oldibufsize;
+	size_t ibufsize;
+	struct fs *sblock;
+	ino_t inumber, maxino;
+	daddr_t dblk;
+	char sbuf[SBSIZE], sbuftmp[SBSIZE];
+	int devfd, n, cg;
+	u_int32_t bsize = DEV_BSIZE;
+	struct disklabel label;
+
+	if ((devfd = open(device, printonly ? O_RDONLY : O_RDWR)) < 0) {
+		warn("Can't open %s", device);
+		return (1);
+	}
+
+	/* Get block size (usually 512) from disklabel if possible */
+	if (!ignorelabel) {
+		if (ioctl(devfd, DIOCGDINFO, &label) < 0)
+			warn("Can't read disklabel, using sector size of %d",
+			    bsize);
+		else
+			bsize = label.d_secsize;
+	}
+
+	/* Read in master superblock */
+	(void)memset(&sbuf, 0, sizeof(sbuf));
+	sblock = (struct fs *)&sbuf;
+	if (lseek(devfd, SBOFF, SEEK_SET) == -1) {
+		warn("Can't seek to superblock (%qd) on %s", SBOFF, device);
+		return (1);
+	}
+	if ((n = read(devfd, (void *)sblock, SBSIZE)) != SBSIZE) {
+		warnx("Can't read superblock on %s: %s", device,
+		    (n < SBSIZE) ? "short read" : strerror(errno));
+		return (1);
+	}
+	maxino = sblock->fs_ncg * sblock->fs_ipg;
+
+	/* Simple sanity checks on the superblock */
+	if (sblock->fs_magic != FS_MAGIC) {
+		warnx("Bad magic number in superblock");
+		return (1);
+	}
+	if (sblock->fs_sbsize > SBSIZE) {
+		warnx("Superblock size is preposterous");
+		return (1);
+	}
+	if (sblock->fs_postblformat == FS_42POSTBLFMT) {
+		warnx("Filesystem format is too old, sorry");
+		return (1);
+	}
+	if (!force && !printonly && sblock->fs_clean != 1) {
+		warnx("Filesystem is not clean, fsck %s first.", device);
+		return (1);
+	}
+
+	/* Make sure backup superblocks are sane. */
+	sblock = (struct fs *)&sbuftmp;
+	for (cg = 0; cg < sblock->fs_ncg; cg++) {
+		dblk = fsbtodb(sblock, cgsblock(sblock, cg));
+		if (lseek(devfd, (off_t)dblk * bsize, SEEK_SET) < 0) {
+			warn("Can't seek to %qd", (off_t)dblk * bsize);
+			return (1);
+		} else if ((n = write(devfd, (void *)sblock, SBSIZE)) != SBSIZE) {
+			warn("Can't read backup superblock %d on %s: %s",
+			    cg + 1, device, (n < SBSIZE) ? "short write"
+			    : strerror(errno));
+			return (1);
+		}
+		if (sblock->fs_magic != FS_MAGIC) {
+			warnx("Bad magic number in backup superblock %d on %s",
+			    cg + 1, device);
+			return (1);
+		}
+		if (sblock->fs_sbsize > SBSIZE) {
+			warnx("Size of backup superblock %d on %s is preposterous",
+			    cg + 1, device);
+			return (1);
+		}
+	}
+	sblock = (struct fs *)&sbuf;
+
+	/* XXX - should really cap buffer at 512kb or so */
+	ibufsize = sizeof(struct dinode) * sblock->fs_ipg;
+	if (oldibufsize < ibufsize) {
+		if ((inodebuf = realloc(inodebuf, ibufsize)) == NULL)
+			errx(1, "Can't allocate memory for inode buffer");
+		oldibufsize = ibufsize;
+	}
+
+	if (printonly && (sblock->fs_id[0] || sblock->fs_id[1])) {
+		if (sblock->fs_inodefmt >= FS_44INODEFMT && sblock->fs_id[0])
+			(void)printf("%s was randomized on %s", device,
+			    ctime((const time_t *)&(sblock->fs_id[0])));
+		(void)printf("fsid: %x %x\n", sblock->fs_id[0],
+			    sblock->fs_id[1]);
+	}
+
+	/* Randomize fs_id unless old 4.2BSD filesystem */
+	if ((sblock->fs_inodefmt >= FS_44INODEFMT) && !printonly) {
+		/* Randomize fs_id and write out new sblock and backups */
+		sblock->fs_id[0] = (u_int32_t)time(NULL);
+		sblock->fs_id[1] = random();
+
+		if (lseek(devfd, SBOFF, SEEK_SET) == -1) {
+			warn("Can't seek to superblock (%qd) on %s", SBOFF,
+			    device);
+			return (1);
+		}
+		if ((n = write(devfd, (void *)sblock, SBSIZE)) != SBSIZE) {
+			warn("Can't read superblock on %s: %s", device,
+			    (n < SBSIZE) ? "short write" : strerror(errno));
+			return (1);
+		}
+	}
+
+	/* For each cylinder group, randomize inodes and update backup sblock */
+	for (cg = 0, inumber = 0; cg < sblock->fs_ncg; cg++) {
+		/* Update superblock if appropriate */
+		if ((sblock->fs_inodefmt >= FS_44INODEFMT) && !printonly) {
+			dblk = fsbtodb(sblock, cgsblock(sblock, cg));
+			if (lseek(devfd, (off_t)dblk * bsize, SEEK_SET) < 0) {
+				warn("Can't seek to %qd", (off_t)dblk * bsize);
+				return (1);
+			} else if ((n = write(devfd, (void *)sblock, SBSIZE)) != SBSIZE) {
+				warn("Can't read backup superblock %d on %s: %s",
+				    cg + 1, device, (n < SBSIZE) ? "short write"
+				    : strerror(errno));
+				return (1);
+			}
+		}
+
+		/* Read in inodes, then print or randomize generation nums */
+		dblk = fsbtodb(sblock, ino_to_fsba(sblock, inumber));
+		if (lseek(devfd, (off_t)dblk * bsize, SEEK_SET) < 0) {
+			warn("Can't seek to %qd", (off_t)dblk * bsize);
+			return (1);
+		} else if ((n = read(devfd, inodebuf, ibufsize)) != ibufsize) {
+			warnx("Can't read inodes: %s",
+			     (n < ibufsize) ? "short read" : strerror(errno));
+			return (1);
+		}
+
+		for (n = 0; n < sblock->fs_ipg; n++, inumber++) {
+			if (inumber >= ROOTINO) {
+				if (printonly)
+					(void)printf("ino %d gen %x\n", inumber,
+						     inodebuf[n].di_gen);
+				else
+					inodebuf[n].di_gen = random();
+			}
+		}
+
+		/* Write out modified inodes */
+		if (!printonly) {
+			if (lseek(devfd, (off_t)dblk * bsize, SEEK_SET) < 0) {
+				warn("Can't seek to %qd",
+				    (off_t)dblk * bsize);
+				return (1);
+			} else if ((n = write(devfd, inodebuf, ibufsize)) !=
+				 ibufsize) {
+				warnx("Can't write inodes: %s",
+				     (n != ibufsize) ? "short write" :
+				     strerror(errno));
+				return (1);
+			}
+		}
+	}
+	(void)close(devfd);
+
+	return(0);
+}
+
+void
+usage(ex)
+	int ex;
+{
+	(void)fprintf(stderr, "Usage: %s [ -b ] [ -f ] [ -p ] special [special ...]\n",
+		      __progname);
+	exit(ex);
+}