Index: head/usr.sbin/freebsd-update/freebsd-update.sh
===================================================================
--- head/usr.sbin/freebsd-update/freebsd-update.sh	(revision 343410)
+++ head/usr.sbin/freebsd-update/freebsd-update.sh	(revision 343411)
@@ -1,3338 +1,3347 @@
 #!/bin/sh
 
 #-
 # SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 #
 # Copyright 2004-2007 Colin Percival
 # All rights reserved
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted providing 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.
 #
 # THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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.
 
 # $FreeBSD$
 
 #### Usage function -- called from command-line handling code.
 
 # Usage instructions.  Options not listed:
 # --debug	-- don't filter output from utilities
 # --no-stats	-- don't show progress statistics while fetching files
 usage () {
 	cat <<EOF
 usage: `basename $0` [options] command ... [path]
 
 Options:
   -b basedir   -- Operate on a system mounted at basedir
                   (default: /)
   -d workdir   -- Store working files in workdir
                   (default: /var/db/freebsd-update/)
   -f conffile  -- Read configuration options from conffile
                   (default: /etc/freebsd-update.conf)
   -F           -- Force a fetch operation to proceed
   -k KEY       -- Trust an RSA key with SHA256 hash of KEY
   -r release   -- Target for upgrade (e.g., 11.1-RELEASE)
   -s server    -- Server from which to fetch updates
                   (default: update.FreeBSD.org)
   -t address   -- Mail output of cron command, if any, to address
                   (default: root)
   --not-running-from-cron
                -- Run without a tty, for use by automated tools
   --currently-running release
                -- Update as if currently running this release
 Commands:
   fetch        -- Fetch updates from server
   cron         -- Sleep rand(3600) seconds, fetch updates, and send an
                   email if updates were found
   upgrade      -- Fetch upgrades to FreeBSD version specified via -r option
   install      -- Install downloaded updates or upgrades
   rollback     -- Uninstall most recently installed updates
   IDS          -- Compare the system against an index of "known good" files.
 EOF
 	exit 0
 }
 
 #### Configuration processing functions
 
 #-
 # Configuration options are set in the following order of priority:
 # 1. Command line options
 # 2. Configuration file options
 # 3. Default options
 # In addition, certain options (e.g., IgnorePaths) can be specified multiple
 # times and (as long as these are all in the same place, e.g., inside the
 # configuration file) they will accumulate.  Finally, because the path to the
 # configuration file can be specified at the command line, the entire command
 # line must be processed before we start reading the configuration file.
 #
 # Sound like a mess?  It is.  Here's how we handle this:
 # 1. Initialize CONFFILE and all the options to "".
 # 2. Process the command line.  Throw an error if a non-accumulating option
 #    is specified twice.
 # 3. If CONFFILE is "", set CONFFILE to /etc/freebsd-update.conf .
 # 4. For all the configuration options X, set X_saved to X.
 # 5. Initialize all the options to "".
 # 6. Read CONFFILE line by line, parsing options.
 # 7. For each configuration option X, set X to X_saved iff X_saved is not "".
 # 8. Repeat steps 4-7, except setting options to their default values at (6).
 
 CONFIGOPTIONS="KEYPRINT WORKDIR SERVERNAME MAILTO ALLOWADD ALLOWDELETE
     KEEPMODIFIEDMETADATA COMPONENTS IGNOREPATHS UPDATEIFUNMODIFIED
     BASEDIR VERBOSELEVEL TARGETRELEASE STRICTCOMPONENTS MERGECHANGES
     IDSIGNOREPATHS BACKUPKERNEL BACKUPKERNELDIR BACKUPKERNELSYMBOLFILES"
 
 # Set all the configuration options to "".
 nullconfig () {
 	for X in ${CONFIGOPTIONS}; do
 		eval ${X}=""
 	done
 }
 
 # For each configuration option X, set X_saved to X.
 saveconfig () {
 	for X in ${CONFIGOPTIONS}; do
 		eval ${X}_saved=\$${X}
 	done
 }
 
 # For each configuration option X, set X to X_saved if X_saved is not "".
 mergeconfig () {
 	for X in ${CONFIGOPTIONS}; do
 		eval _=\$${X}_saved
 		if ! [ -z "${_}" ]; then
 			eval ${X}=\$${X}_saved
 		fi
 	done
 }
 
 # Set the trusted keyprint.
 config_KeyPrint () {
 	if [ -z ${KEYPRINT} ]; then
 		KEYPRINT=$1
 	else
 		return 1
 	fi
 }
 
 # Set the working directory.
 config_WorkDir () {
 	if [ -z ${WORKDIR} ]; then
 		WORKDIR=$1
 	else
 		return 1
 	fi
 }
 
 # Set the name of the server (pool) from which to fetch updates
 config_ServerName () {
 	if [ -z ${SERVERNAME} ]; then
 		SERVERNAME=$1
 	else
 		return 1
 	fi
 }
 
 # Set the address to which 'cron' output will be mailed.
 config_MailTo () {
 	if [ -z ${MAILTO} ]; then
 		MAILTO=$1
 	else
 		return 1
 	fi
 }
 
 # Set whether FreeBSD Update is allowed to add files (or directories, or
 # symlinks) which did not previously exist.
 config_AllowAdd () {
 	if [ -z ${ALLOWADD} ]; then
 		case $1 in
 		[Yy][Ee][Ss])
 			ALLOWADD=yes
 			;;
 		[Nn][Oo])
 			ALLOWADD=no
 			;;
 		*)
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 # Set whether FreeBSD Update is allowed to remove files/directories/symlinks.
 config_AllowDelete () {
 	if [ -z ${ALLOWDELETE} ]; then
 		case $1 in
 		[Yy][Ee][Ss])
 			ALLOWDELETE=yes
 			;;
 		[Nn][Oo])
 			ALLOWDELETE=no
 			;;
 		*)
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 # Set whether FreeBSD Update should keep existing inode ownership,
 # permissions, and flags, in the event that they have been modified locally
 # after the release.
 config_KeepModifiedMetadata () {
 	if [ -z ${KEEPMODIFIEDMETADATA} ]; then
 		case $1 in
 		[Yy][Ee][Ss])
 			KEEPMODIFIEDMETADATA=yes
 			;;
 		[Nn][Oo])
 			KEEPMODIFIEDMETADATA=no
 			;;
 		*)
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 # Add to the list of components which should be kept updated.
 config_Components () {
 	for C in $@; do
 		if [ "$C" = "src" ]; then
 			if [ -e "${BASEDIR}/usr/src/COPYRIGHT" ]; then
 				COMPONENTS="${COMPONENTS} ${C}"
 			else
 				echo "src component not installed, skipped"
 			fi
 		else
 			COMPONENTS="${COMPONENTS} ${C}"
 		fi
 	done
 }
 
 # Add to the list of paths under which updates will be ignored.
 config_IgnorePaths () {
 	for C in $@; do
 		IGNOREPATHS="${IGNOREPATHS} ${C}"
 	done
 }
 
 # Add to the list of paths which IDS should ignore.
 config_IDSIgnorePaths () {
 	for C in $@; do
 		IDSIGNOREPATHS="${IDSIGNOREPATHS} ${C}"
 	done
 }
 
 # Add to the list of paths within which updates will be performed only if the
 # file on disk has not been modified locally.
 config_UpdateIfUnmodified () {
 	for C in $@; do
 		UPDATEIFUNMODIFIED="${UPDATEIFUNMODIFIED} ${C}"
 	done
 }
 
 # Add to the list of paths within which updates to text files will be merged
 # instead of overwritten.
 config_MergeChanges () {
 	for C in $@; do
 		MERGECHANGES="${MERGECHANGES} ${C}"
 	done
 }
 
 # Work on a FreeBSD installation mounted under $1
 config_BaseDir () {
 	if [ -z ${BASEDIR} ]; then
 		BASEDIR=$1
 	else
 		return 1
 	fi
 }
 
 # When fetching upgrades, should we assume the user wants exactly the
 # components listed in COMPONENTS, rather than trying to guess based on
 # what's currently installed?
 config_StrictComponents () {
 	if [ -z ${STRICTCOMPONENTS} ]; then
 		case $1 in
 		[Yy][Ee][Ss])
 			STRICTCOMPONENTS=yes
 			;;
 		[Nn][Oo])
 			STRICTCOMPONENTS=no
 			;;
 		*)
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 # Upgrade to FreeBSD $1
 config_TargetRelease () {
 	if [ -z ${TARGETRELEASE} ]; then
 		TARGETRELEASE=$1
 	else
 		return 1
 	fi
 	if echo ${TARGETRELEASE} | grep -qE '^[0-9.]+$'; then
 		TARGETRELEASE="${TARGETRELEASE}-RELEASE"
 	fi
 }
 
 # Pretend current release is FreeBSD $1
 config_SourceRelease () {
 	UNAME_r=$1
 	if echo ${UNAME_r} | grep -qE '^[0-9.]+$'; then
 		UNAME_r="${UNAME_r}-RELEASE"
 	fi
 	export UNAME_r
 }
 
 # Define what happens to output of utilities
 config_VerboseLevel () {
 	if [ -z ${VERBOSELEVEL} ]; then
 		case $1 in
 		[Dd][Ee][Bb][Uu][Gg])
 			VERBOSELEVEL=debug
 			;;
 		[Nn][Oo][Ss][Tt][Aa][Tt][Ss])
 			VERBOSELEVEL=nostats
 			;;
 		[Ss][Tt][Aa][Tt][Ss])
 			VERBOSELEVEL=stats
 			;;
 		*)
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 config_BackupKernel () {
 	if [ -z ${BACKUPKERNEL} ]; then
 		case $1 in
 		[Yy][Ee][Ss])
 			BACKUPKERNEL=yes
 			;;
 		[Nn][Oo])
 			BACKUPKERNEL=no
 			;;
 		*)
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 config_BackupKernelDir () {
 	if [ -z ${BACKUPKERNELDIR} ]; then
 		if [ -z "$1" ]; then
 			echo "BackupKernelDir set to empty dir"
 			return 1
 		fi
 
 		# We check for some paths which would be extremely odd
 		# to use, but which could cause a lot of problems if
 		# used.
 		case $1 in
 		/|/bin|/boot|/etc|/lib|/libexec|/sbin|/usr|/var)
 			echo "BackupKernelDir set to invalid path $1"
 			return 1
 			;;
 		/*)
 			BACKUPKERNELDIR=$1
 			;;
 		*)
 			echo "BackupKernelDir ($1) is not an absolute path"
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 config_BackupKernelSymbolFiles () {
 	if [ -z ${BACKUPKERNELSYMBOLFILES} ]; then
 		case $1 in
 		[Yy][Ee][Ss])
 			BACKUPKERNELSYMBOLFILES=yes
 			;;
 		[Nn][Oo])
 			BACKUPKERNELSYMBOLFILES=no
 			;;
 		*)
 			return 1
 			;;
 		esac
 	else
 		return 1
 	fi
 }
 
 # Handle one line of configuration
 configline () {
 	if [ $# -eq 0 ]; then
 		return
 	fi
 
 	OPT=$1
 	shift
 	config_${OPT} $@
 }
 
 #### Parameter handling functions.
 
 # Initialize parameters to null, just in case they're
 # set in the environment.
 init_params () {
 	# Configration settings
 	nullconfig
 
 	# No configuration file set yet
 	CONFFILE=""
 
 	# No commands specified yet
 	COMMANDS=""
 
 	# Force fetch to proceed
 	FORCEFETCH=0
 
 	# Run without a TTY
 	NOTTYOK=0
 
 	# Fetched first in a chain of commands
 	ISFETCHED=0
 }
 
 # Parse the command line
 parse_cmdline () {
 	while [ $# -gt 0 ]; do
 		case "$1" in
 		# Location of configuration file
 		-f)
 			if [ $# -eq 1 ]; then usage; fi
 			if [ ! -z "${CONFFILE}" ]; then usage; fi
 			shift; CONFFILE="$1"
 			;;
 		-F)
 			FORCEFETCH=1
 			;;
 		--not-running-from-cron)
 			NOTTYOK=1
 			;;
 		--currently-running)
 			shift
 			config_SourceRelease $1 || usage
 			;;
 
 		# Configuration file equivalents
 		-b)
 			if [ $# -eq 1 ]; then usage; fi; shift
 			config_BaseDir $1 || usage
 			;;
 		-d)
 			if [ $# -eq 1 ]; then usage; fi; shift
 			config_WorkDir $1 || usage
 			;;
 		-k)
 			if [ $# -eq 1 ]; then usage; fi; shift
 			config_KeyPrint $1 || usage
 			;;
 		-s)
 			if [ $# -eq 1 ]; then usage; fi; shift
 			config_ServerName $1 || usage
 			;;
 		-r)
 			if [ $# -eq 1 ]; then usage; fi; shift
 			config_TargetRelease $1 || usage
 			;;
 		-t)
 			if [ $# -eq 1 ]; then usage; fi; shift
 			config_MailTo $1 || usage
 			;;
 		-v)
 			if [ $# -eq 1 ]; then usage; fi; shift
 			config_VerboseLevel $1 || usage
 			;;
 
 		# Aliases for "-v debug" and "-v nostats"
 		--debug)
 			config_VerboseLevel debug || usage
 			;;
 		--no-stats)
 			config_VerboseLevel nostats || usage
 			;;
 
 		# Commands
 		cron | fetch | upgrade | install | rollback | IDS)
 			COMMANDS="${COMMANDS} $1"
 			;;
 
 		# Anything else is an error
 		*)
 			usage
 			;;
 		esac
 		shift
 	done
 
 	# Make sure we have at least one command
 	if [ -z "${COMMANDS}" ]; then
 		usage
 	fi
 }
 
 # Parse the configuration file
 parse_conffile () {
 	# If a configuration file was specified on the command line, check
 	# that it exists and is readable.
 	if [ ! -z "${CONFFILE}" ] && [ ! -r "${CONFFILE}" ]; then
 		echo -n "File does not exist "
 		echo -n "or is not readable: "
 		echo ${CONFFILE}
 		exit 1
 	fi
 
 	# If a configuration file was not specified on the command line,
 	# use the default configuration file path.  If that default does
 	# not exist, give up looking for any configuration.
 	if [ -z "${CONFFILE}" ]; then
 		CONFFILE="/etc/freebsd-update.conf"
 		if [ ! -r "${CONFFILE}" ]; then
 			return
 		fi
 	fi
 
 	# Save the configuration options specified on the command line, and
 	# clear all the options in preparation for reading the config file.
 	saveconfig
 	nullconfig
 
 	# Read the configuration file.  Anything after the first '#' is
 	# ignored, and any blank lines are ignored.
 	L=0
 	while read LINE; do
 		L=$(($L + 1))
 		LINEX=`echo "${LINE}" | cut -f 1 -d '#'`
 		if ! configline ${LINEX}; then
 			echo "Error processing configuration file, line $L:"
 			echo "==> ${LINE}"
 			exit 1
 		fi
 	done < ${CONFFILE}
 
 	# Merge the settings read from the configuration file with those
 	# provided at the command line.
 	mergeconfig
 }
 
 # Provide some default parameters
 default_params () {
 	# Save any parameters already configured, and clear the slate
 	saveconfig
 	nullconfig
 
 	# Default configurations
 	config_WorkDir /var/db/freebsd-update
 	config_MailTo root
 	config_AllowAdd yes
 	config_AllowDelete yes
 	config_KeepModifiedMetadata yes
 	config_BaseDir /
 	config_VerboseLevel stats
 	config_StrictComponents no
 	config_BackupKernel yes
 	config_BackupKernelDir /boot/kernel.old
 	config_BackupKernelSymbolFiles no
 
 	# Merge these defaults into the earlier-configured settings
 	mergeconfig
 }
 
 # Set utility output filtering options, based on ${VERBOSELEVEL}
 fetch_setup_verboselevel () {
 	case ${VERBOSELEVEL} in
 	debug)
 		QUIETREDIR="/dev/stderr"
 		QUIETFLAG=" "
 		STATSREDIR="/dev/stderr"
 		DDSTATS=".."
 		XARGST="-t"
 		NDEBUG=" "
 		;;
 	nostats)
 		QUIETREDIR=""
 		QUIETFLAG=""
 		STATSREDIR="/dev/null"
 		DDSTATS=".."
 		XARGST=""
 		NDEBUG=""
 		;;
 	stats)
 		QUIETREDIR="/dev/null"
 		QUIETFLAG="-q"
 		STATSREDIR="/dev/stdout"
 		DDSTATS=""
 		XARGST=""
 		NDEBUG="-n"
 		;;
 	esac
 }
 
 # Perform sanity checks and set some final parameters
 # in preparation for fetching files.  Figure out which
 # set of updates should be downloaded: If the user is
 # running *-p[0-9]+, strip off the last part; if the
 # user is running -SECURITY, call it -RELEASE.  Chdir
 # into the working directory.
 fetchupgrade_check_params () {
 	export HTTP_USER_AGENT="freebsd-update (${COMMAND}, `uname -r`)"
 
 	_SERVERNAME_z=\
 "SERVERNAME must be given via command line or configuration file."
 	_KEYPRINT_z="Key must be given via -k option or configuration file."
 	_KEYPRINT_bad="Invalid key fingerprint: "
 	_WORKDIR_bad="Directory does not exist or is not writable: "
 	_WORKDIR_bad2="Directory is not on a persistent filesystem: "
 
 	if [ -z "${SERVERNAME}" ]; then
 		echo -n "`basename $0`: "
 		echo "${_SERVERNAME_z}"
 		exit 1
 	fi
 	if [ -z "${KEYPRINT}" ]; then
 		echo -n "`basename $0`: "
 		echo "${_KEYPRINT_z}"
 		exit 1
 	fi
 	if ! echo "${KEYPRINT}" | grep -qE "^[0-9a-f]{64}$"; then
 		echo -n "`basename $0`: "
 		echo -n "${_KEYPRINT_bad}"
 		echo ${KEYPRINT}
 		exit 1
 	fi
 	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
 		echo -n "`basename $0`: "
 		echo -n "${_WORKDIR_bad}"
 		echo ${WORKDIR}
 		exit 1
 	fi
 	case `df -T ${WORKDIR}` in */dev/md[0-9]* | *tmpfs*)
 		echo -n "`basename $0`: "
 		echo -n "${_WORKDIR_bad2}"
 		echo ${WORKDIR}
 		exit 1
 		;;
 	esac
 	chmod 700 ${WORKDIR}
 	cd ${WORKDIR} || exit 1
 
 	# Generate release number.  The s/SECURITY/RELEASE/ bit exists
 	# to provide an upgrade path for FreeBSD Update 1.x users, since
 	# the kernels provided by FreeBSD Update 1.x are always labelled
 	# as X.Y-SECURITY.
 	RELNUM=`uname -r |
 	    sed -E 's,-p[0-9]+,,' |
 	    sed -E 's,-SECURITY,-RELEASE,'`
 	ARCH=`uname -m`
 	FETCHDIR=${RELNUM}/${ARCH}
 	PATCHDIR=${RELNUM}/${ARCH}/bp
 
 	# Disallow upgrade from a version that is not a release
 	case ${RELNUM} in
 	*-RELEASE | *-ALPHA*  | *-BETA* | *-RC*)
 		;;
 	*)
 		echo -n "`basename $0`: "
 		cat <<- EOF
 			Cannot upgrade from a version that is not a release
 			(including alpha, beta and release candidates)
 			using `basename $0`. Instead, FreeBSD can be directly
 			upgraded by source or upgraded to a RELEASE/RELENG version
 			prior to running `basename $0`.
 			Currently running: ${RELNUM}
 		EOF
 		exit 1
 		;;
 	esac
 
 	# Figure out what directory contains the running kernel
 	BOOTFILE=`sysctl -n kern.bootfile`
 	KERNELDIR=${BOOTFILE%/kernel}
 	if ! [ -d ${KERNELDIR} ]; then
 		echo "Cannot identify running kernel"
 		exit 1
 	fi
 
 	# Figure out what kernel configuration is running.  We start with
 	# the output of `uname -i`, and then make the following adjustments:
 	# 1. Replace "SMP-GENERIC" with "SMP".  Why the SMP kernel config
 	# file says "ident SMP-GENERIC", I don't know...
 	# 2. If the kernel claims to be GENERIC _and_ ${ARCH} is "amd64"
 	# _and_ `sysctl kern.version` contains a line which ends "/SMP", then
 	# we're running an SMP kernel.  This mis-identification is a bug
 	# which was fixed in 6.2-STABLE.
 	KERNCONF=`uname -i`
 	if [ ${KERNCONF} = "SMP-GENERIC" ]; then
 		KERNCONF=SMP
 	fi
 	if [ ${KERNCONF} = "GENERIC" ] && [ ${ARCH} = "amd64" ]; then
 		if sysctl kern.version | grep -qE '/SMP$'; then
 			KERNCONF=SMP
 		fi
 	fi
 
 	# Define some paths
 	BSPATCH=/usr/bin/bspatch
 	SHA256=/sbin/sha256
 	PHTTPGET=/usr/libexec/phttpget
 
 	# Set up variables relating to VERBOSELEVEL
 	fetch_setup_verboselevel
 
 	# Construct a unique name from ${BASEDIR}
 	BDHASH=`echo ${BASEDIR} | sha256 -q`
 }
 
 # Perform sanity checks etc. before fetching updates.
 fetch_check_params () {
 	fetchupgrade_check_params
 
 	if ! [ -z "${TARGETRELEASE}" ]; then
 		echo -n "`basename $0`: "
 		echo -n "-r option is meaningless with 'fetch' command.  "
 		echo "(Did you mean 'upgrade' instead?)"
 		exit 1
 	fi
 
 	# Check that we have updates ready to install
 	if [ -f ${BDHASH}-install/kerneldone -a $FORCEFETCH -eq 0 ]; then
 		echo "You have a partially completed upgrade pending"
 		echo "Run '$0 install' first."
 		echo "Run '$0 fetch -F' to proceed anyway."
 		exit 1
 	fi
 }
 
 # Perform sanity checks etc. before fetching upgrades.
 upgrade_check_params () {
 	fetchupgrade_check_params
 
 	# Unless set otherwise, we're upgrading to the same kernel config.
 	NKERNCONF=${KERNCONF}
 
 	# We need TARGETRELEASE set
 	_TARGETRELEASE_z="Release target must be specified via -r option."
 	if [ -z "${TARGETRELEASE}" ]; then
 		echo -n "`basename $0`: "
 		echo "${_TARGETRELEASE_z}"
 		exit 1
 	fi
 
 	# The target release should be != the current release.
 	if [ "${TARGETRELEASE}" = "${RELNUM}" ]; then
 		echo -n "`basename $0`: "
 		echo "Cannot upgrade from ${RELNUM} to itself"
 		exit 1
 	fi
 
 	# Turning off AllowAdd or AllowDelete is a bad idea for upgrades.
 	if [ "${ALLOWADD}" = "no" ]; then
 		echo -n "`basename $0`: "
 		echo -n "WARNING: \"AllowAdd no\" is a bad idea "
 		echo "when upgrading between releases."
 		echo
 	fi
 	if [ "${ALLOWDELETE}" = "no" ]; then
 		echo -n "`basename $0`: "
 		echo -n "WARNING: \"AllowDelete no\" is a bad idea "
 		echo "when upgrading between releases."
 		echo
 	fi
 
 	# Set EDITOR to /usr/bin/vi if it isn't already set
 	: ${EDITOR:='/usr/bin/vi'}
 }
 
 # Perform sanity checks and set some final parameters in
 # preparation for installing updates.
 install_check_params () {
 	# Check that we are root.  All sorts of things won't work otherwise.
 	if [ `id -u` != 0 ]; then
 		echo "You must be root to run this."
 		exit 1
 	fi
 
 	# Check that securelevel <= 0.  Otherwise we can't update schg files.
 	if [ `sysctl -n kern.securelevel` -gt 0 ]; then
 		echo "Updates cannot be installed when the system securelevel"
 		echo "is greater than zero."
 		exit 1
 	fi
 
 	# Check that we have a working directory
 	_WORKDIR_bad="Directory does not exist or is not writable: "
 	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
 		echo -n "`basename $0`: "
 		echo -n "${_WORKDIR_bad}"
 		echo ${WORKDIR}
 		exit 1
 	fi
 	cd ${WORKDIR} || exit 1
 
 	# Construct a unique name from ${BASEDIR}
 	BDHASH=`echo ${BASEDIR} | sha256 -q`
 
 	# Check that we have updates ready to install
 	if ! [ -L ${BDHASH}-install ]; then
 		echo "No updates are available to install."
 		if [ $ISFETCHED -eq 0 ]; then
 			echo "Run '$0 fetch' first."
 		fi
 		exit 0
 	fi
 	if ! [ -f ${BDHASH}-install/INDEX-OLD ] ||
 	    ! [ -f ${BDHASH}-install/INDEX-NEW ]; then
 		echo "Update manifest is corrupt -- this should never happen."
 		echo "Re-run '$0 fetch'."
 		exit 1
 	fi
 
 	# Figure out what directory contains the running kernel
 	BOOTFILE=`sysctl -n kern.bootfile`
 	KERNELDIR=${BOOTFILE%/kernel}
 	if ! [ -d ${KERNELDIR} ]; then
 		echo "Cannot identify running kernel"
 		exit 1
 	fi
 }
 
 # Perform sanity checks and set some final parameters in
 # preparation for UNinstalling updates.
 rollback_check_params () {
 	# Check that we are root.  All sorts of things won't work otherwise.
 	if [ `id -u` != 0 ]; then
 		echo "You must be root to run this."
 		exit 1
 	fi
 
 	# Check that we have a working directory
 	_WORKDIR_bad="Directory does not exist or is not writable: "
 	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
 		echo -n "`basename $0`: "
 		echo -n "${_WORKDIR_bad}"
 		echo ${WORKDIR}
 		exit 1
 	fi
 	cd ${WORKDIR} || exit 1
 
 	# Construct a unique name from ${BASEDIR}
 	BDHASH=`echo ${BASEDIR} | sha256 -q`
 
 	# Check that we have updates ready to rollback
 	if ! [ -L ${BDHASH}-rollback ]; then
 		echo "No rollback directory found."
 		exit 1
 	fi
 	if ! [ -f ${BDHASH}-rollback/INDEX-OLD ] ||
 	    ! [ -f ${BDHASH}-rollback/INDEX-NEW ]; then
 		echo "Update manifest is corrupt -- this should never happen."
 		exit 1
 	fi
 }
 
 # Perform sanity checks and set some final parameters
 # in preparation for comparing the system against the
 # published index.  Figure out which index we should
 # compare against: If the user is running *-p[0-9]+,
 # strip off the last part; if the user is running
 # -SECURITY, call it -RELEASE.  Chdir into the working
 # directory.
 IDS_check_params () {
 	export HTTP_USER_AGENT="freebsd-update (${COMMAND}, `uname -r`)"
 
 	_SERVERNAME_z=\
 "SERVERNAME must be given via command line or configuration file."
 	_KEYPRINT_z="Key must be given via -k option or configuration file."
 	_KEYPRINT_bad="Invalid key fingerprint: "
 	_WORKDIR_bad="Directory does not exist or is not writable: "
 
 	if [ -z "${SERVERNAME}" ]; then
 		echo -n "`basename $0`: "
 		echo "${_SERVERNAME_z}"
 		exit 1
 	fi
 	if [ -z "${KEYPRINT}" ]; then
 		echo -n "`basename $0`: "
 		echo "${_KEYPRINT_z}"
 		exit 1
 	fi
 	if ! echo "${KEYPRINT}" | grep -qE "^[0-9a-f]{64}$"; then
 		echo -n "`basename $0`: "
 		echo -n "${_KEYPRINT_bad}"
 		echo ${KEYPRINT}
 		exit 1
 	fi
 	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
 		echo -n "`basename $0`: "
 		echo -n "${_WORKDIR_bad}"
 		echo ${WORKDIR}
 		exit 1
 	fi
 	cd ${WORKDIR} || exit 1
 
 	# Generate release number.  The s/SECURITY/RELEASE/ bit exists
 	# to provide an upgrade path for FreeBSD Update 1.x users, since
 	# the kernels provided by FreeBSD Update 1.x are always labelled
 	# as X.Y-SECURITY.
 	RELNUM=`uname -r |
 	    sed -E 's,-p[0-9]+,,' |
 	    sed -E 's,-SECURITY,-RELEASE,'`
 	ARCH=`uname -m`
 	FETCHDIR=${RELNUM}/${ARCH}
 	PATCHDIR=${RELNUM}/${ARCH}/bp
 
 	# Figure out what directory contains the running kernel
 	BOOTFILE=`sysctl -n kern.bootfile`
 	KERNELDIR=${BOOTFILE%/kernel}
 	if ! [ -d ${KERNELDIR} ]; then
 		echo "Cannot identify running kernel"
 		exit 1
 	fi
 
 	# Figure out what kernel configuration is running.  We start with
 	# the output of `uname -i`, and then make the following adjustments:
 	# 1. Replace "SMP-GENERIC" with "SMP".  Why the SMP kernel config
 	# file says "ident SMP-GENERIC", I don't know...
 	# 2. If the kernel claims to be GENERIC _and_ ${ARCH} is "amd64"
 	# _and_ `sysctl kern.version` contains a line which ends "/SMP", then
 	# we're running an SMP kernel.  This mis-identification is a bug
 	# which was fixed in 6.2-STABLE.
 	KERNCONF=`uname -i`
 	if [ ${KERNCONF} = "SMP-GENERIC" ]; then
 		KERNCONF=SMP
 	fi
 	if [ ${KERNCONF} = "GENERIC" ] && [ ${ARCH} = "amd64" ]; then
 		if sysctl kern.version | grep -qE '/SMP$'; then
 			KERNCONF=SMP
 		fi
 	fi
 
 	# Define some paths
 	SHA256=/sbin/sha256
 	PHTTPGET=/usr/libexec/phttpget
 
 	# Set up variables relating to VERBOSELEVEL
 	fetch_setup_verboselevel
 }
 
 #### Core functionality -- the actual work gets done here
 
 # Use an SRV query to pick a server.  If the SRV query doesn't provide
 # a useful answer, use the server name specified by the user.
 # Put another way... look up _http._tcp.${SERVERNAME} and pick a server
 # from that; or if no servers are returned, use ${SERVERNAME}.
 # This allows a user to specify "portsnap.freebsd.org" (in which case
 # portsnap will select one of the mirrors) or "portsnap5.tld.freebsd.org"
 # (in which case portsnap will use that particular server, since there
 # won't be an SRV entry for that name).
 #
 # We ignore the Port field, since we are always going to use port 80.
 
 # Fetch the mirror list, but do not pick a mirror yet.  Returns 1 if
 # no mirrors are available for any reason.
 fetch_pick_server_init () {
 	: > serverlist_tried
 
 # Check that host(1) exists (i.e., that the system wasn't built with the
 # WITHOUT_BIND set) and don't try to find a mirror if it doesn't exist.
 	if ! which -s host; then
 		: > serverlist_full
 		return 1
 	fi
 
 	echo -n "Looking up ${SERVERNAME} mirrors... "
 
 # Issue the SRV query and pull out the Priority, Weight, and Target fields.
 # BIND 9 prints "$name has SRV record ..." while BIND 8 prints
 # "$name server selection ..."; we allow either format.
 	MLIST="_http._tcp.${SERVERNAME}"
 	host -t srv "${MLIST}" |
 	    sed -nE "s/${MLIST} (has SRV record|server selection) //Ip" |
 	    cut -f 1,2,4 -d ' ' |
 	    sed -e 's/\.$//' |
 	    sort > serverlist_full
 
 # If no records, give up -- we'll just use the server name we were given.
 	if [ `wc -l < serverlist_full` -eq 0 ]; then
 		echo "none found."
 		return 1
 	fi
 
 # Report how many mirrors we found.
 	echo `wc -l < serverlist_full` "mirrors found."
 
 # Generate a random seed for use in picking mirrors.  If HTTP_PROXY
 # is set, this will be used to generate the seed; otherwise, the seed
 # will be random.
 	if [ -n "${HTTP_PROXY}${http_proxy}" ]; then
 		RANDVALUE=`sha256 -qs "${HTTP_PROXY}${http_proxy}" |
 		    tr -d 'a-f' |
 		    cut -c 1-9`
 	else
 		RANDVALUE=`jot -r 1 0 999999999`
 	fi
 }
 
 # Pick a mirror.  Returns 1 if we have run out of mirrors to try.
 fetch_pick_server () {
 # Generate a list of not-yet-tried mirrors
 	sort serverlist_tried |
 	    comm -23 serverlist_full - > serverlist
 
 # Have we run out of mirrors?
 	if [ `wc -l < serverlist` -eq 0 ]; then
-		echo "No mirrors remaining, giving up."
+		cat <<- EOF
+			No mirrors remaining, giving up.
+
+			This may be because upgrading from this platform (${ARCH})
+			or release (${RELNUM}) is unsupported by `basename $0`. Only
+			platforms with Tier 1 support can be upgraded by `basename $0`.
+			See https://www.freebsd.org/platforms/index.html for more info.
+
+			If unsupported, FreeBSD must be upgraded by source.
+		EOF
 		return 1
 	fi
 
 # Find the highest priority level (lowest numeric value).
 	SRV_PRIORITY=`cut -f 1 -d ' ' serverlist | sort -n | head -1`
 
 # Add up the weights of the response lines at that priority level.
 	SRV_WSUM=0;
 	while read X; do
 		case "$X" in
 		${SRV_PRIORITY}\ *)
 			SRV_W=`echo $X | cut -f 2 -d ' '`
 			SRV_WSUM=$(($SRV_WSUM + $SRV_W))
 			;;
 		esac
 	done < serverlist
 
 # If all the weights are 0, pretend that they are all 1 instead.
 	if [ ${SRV_WSUM} -eq 0 ]; then
 		SRV_WSUM=`grep -E "^${SRV_PRIORITY} " serverlist | wc -l`
 		SRV_W_ADD=1
 	else
 		SRV_W_ADD=0
 	fi
 
 # Pick a value between 0 and the sum of the weights - 1
 	SRV_RND=`expr ${RANDVALUE} % ${SRV_WSUM}`
 
 # Read through the list of mirrors and set SERVERNAME.  Write the line
 # corresponding to the mirror we selected into serverlist_tried so that
 # we won't try it again.
 	while read X; do
 		case "$X" in
 		${SRV_PRIORITY}\ *)
 			SRV_W=`echo $X | cut -f 2 -d ' '`
 			SRV_W=$(($SRV_W + $SRV_W_ADD))
 			if [ $SRV_RND -lt $SRV_W ]; then
 				SERVERNAME=`echo $X | cut -f 3 -d ' '`
 				echo "$X" >> serverlist_tried
 				break
 			else
 				SRV_RND=$(($SRV_RND - $SRV_W))
 			fi
 			;;
 		esac
 	done < serverlist
 }
 
 # Take a list of ${oldhash}|${newhash} and output a list of needed patches,
 # i.e., those for which we have ${oldhash} and don't have ${newhash}.
 fetch_make_patchlist () {
 	grep -vE "^([0-9a-f]{64})\|\1$" |
 	    tr '|' ' ' |
 		while read X Y; do
 			if [ -f "files/${Y}.gz" ] ||
 			    [ ! -f "files/${X}.gz" ]; then
 				continue
 			fi
 			echo "${X}|${Y}"
 		done | sort -u
 }
 
 # Print user-friendly progress statistics
 fetch_progress () {
 	LNC=0
 	while read x; do
 		LNC=$(($LNC + 1))
 		if [ $(($LNC % 10)) = 0 ]; then
 			echo -n $LNC
 		elif [ $(($LNC % 2)) = 0 ]; then
 			echo -n .
 		fi
 	done
 	echo -n " "
 }
 
 # Function for asking the user if everything is ok
 continuep () {
 	while read -p "Does this look reasonable (y/n)? " CONTINUE; do
 		case "${CONTINUE}" in
 		y*)
 			return 0
 			;;
 		n*)
 			return 1
 			;;
 		esac
 	done
 }
 
 # Initialize the working directory
 workdir_init () {
 	mkdir -p files
 	touch tINDEX.present
 }
 
 # Check that we have a public key with an appropriate hash, or
 # fetch the key if it doesn't exist.  Returns 1 if the key has
 # not yet been fetched.
 fetch_key () {
 	if [ -r pub.ssl ] && [ `${SHA256} -q pub.ssl` = ${KEYPRINT} ]; then
 		return 0
 	fi
 
 	echo -n "Fetching public key from ${SERVERNAME}... "
 	rm -f pub.ssl
 	fetch ${QUIETFLAG} http://${SERVERNAME}/${FETCHDIR}/pub.ssl \
 	    2>${QUIETREDIR} || true
 	if ! [ -r pub.ssl ]; then
 		echo "failed."
 		return 1
 	fi
 	if ! [ `${SHA256} -q pub.ssl` = ${KEYPRINT} ]; then
 		echo "key has incorrect hash."
 		rm -f pub.ssl
 		return 1
 	fi
 	echo "done."
 }
 
 # Fetch metadata signature, aka "tag".
 fetch_tag () {
 	echo -n "Fetching metadata signature "
 	echo ${NDEBUG} "for ${RELNUM} from ${SERVERNAME}... "
 	rm -f latest.ssl
 	fetch ${QUIETFLAG} http://${SERVERNAME}/${FETCHDIR}/latest.ssl	\
 	    2>${QUIETREDIR} || true
 	if ! [ -r latest.ssl ]; then
 		echo "failed."
 		return 1
 	fi
 
 	openssl rsautl -pubin -inkey pub.ssl -verify		\
 	    < latest.ssl > tag.new 2>${QUIETREDIR} || true
 	rm latest.ssl
 
 	if ! [ `wc -l < tag.new` = 1 ] ||
 	    ! grep -qE	\
     "^freebsd-update\|${ARCH}\|${RELNUM}\|[0-9]+\|[0-9a-f]{64}\|[0-9]{10}" \
 		tag.new; then
 		echo "invalid signature."
 		return 1
 	fi
 
 	echo "done."
 
 	RELPATCHNUM=`cut -f 4 -d '|' < tag.new`
 	TINDEXHASH=`cut -f 5 -d '|' < tag.new`
 	EOLTIME=`cut -f 6 -d '|' < tag.new`
 }
 
 # Sanity-check the patch number in a tag, to make sure that we're not
 # going to "update" backwards and to prevent replay attacks.
 fetch_tagsanity () {
 	# Check that we're not going to move from -pX to -pY with Y < X.
 	RELPX=`uname -r | sed -E 's,.*-,,'`
 	if echo ${RELPX} | grep -qE '^p[0-9]+$'; then
 		RELPX=`echo ${RELPX} | cut -c 2-`
 	else
 		RELPX=0
 	fi
 	if [ "${RELPATCHNUM}" -lt "${RELPX}" ]; then
 		echo
 		echo -n "Files on mirror (${RELNUM}-p${RELPATCHNUM})"
 		echo " appear older than what"
 		echo "we are currently running (`uname -r`)!"
 		echo "Cowardly refusing to proceed any further."
 		return 1
 	fi
 
 	# If "tag" exists and corresponds to ${RELNUM}, make sure that
 	# it contains a patch number <= RELPATCHNUM, in order to protect
 	# against rollback (replay) attacks.
 	if [ -f tag ] &&
 	    grep -qE	\
     "^freebsd-update\|${ARCH}\|${RELNUM}\|[0-9]+\|[0-9a-f]{64}\|[0-9]{10}" \
 		tag; then
 		LASTRELPATCHNUM=`cut -f 4 -d '|' < tag`
 
 		if [ "${RELPATCHNUM}" -lt "${LASTRELPATCHNUM}" ]; then
 			echo
 			echo -n "Files on mirror (${RELNUM}-p${RELPATCHNUM})"
 			echo " are older than the"
 			echo -n "most recently seen updates"
 			echo " (${RELNUM}-p${LASTRELPATCHNUM})."
 			echo "Cowardly refusing to proceed any further."
 			return 1
 		fi
 	fi
 }
 
 # Fetch metadata index file
 fetch_metadata_index () {
 	echo ${NDEBUG} "Fetching metadata index... "
 	rm -f ${TINDEXHASH}
 	fetch ${QUIETFLAG} http://${SERVERNAME}/${FETCHDIR}/t/${TINDEXHASH}
 	    2>${QUIETREDIR}
 	if ! [ -f ${TINDEXHASH} ]; then
 		echo "failed."
 		return 1
 	fi
 	if [ `${SHA256} -q ${TINDEXHASH}` != ${TINDEXHASH} ]; then
 		echo "update metadata index corrupt."
 		return 1
 	fi
 	echo "done."
 }
 
 # Print an error message about signed metadata being bogus.
 fetch_metadata_bogus () {
 	echo
 	echo "The update metadata$1 is correctly signed, but"
 	echo "failed an integrity check."
 	echo "Cowardly refusing to proceed any further."
 	return 1
 }
 
 # Construct tINDEX.new by merging the lines named in $1 from ${TINDEXHASH}
 # with the lines not named in $@ from tINDEX.present (if that file exists).
 fetch_metadata_index_merge () {
 	for METAFILE in $@; do
 		if [ `grep -E "^${METAFILE}\|" ${TINDEXHASH} | wc -l`	\
 		    -ne 1 ]; then
 			fetch_metadata_bogus " index"
 			return 1
 		fi
 
 		grep -E "${METAFILE}\|" ${TINDEXHASH}
 	done |
 	    sort > tINDEX.wanted
 
 	if [ -f tINDEX.present ]; then
 		join -t '|' -v 2 tINDEX.wanted tINDEX.present |
 		    sort -m - tINDEX.wanted > tINDEX.new
 		rm tINDEX.wanted
 	else
 		mv tINDEX.wanted tINDEX.new
 	fi
 }
 
 # Sanity check all the lines of tINDEX.new.  Even if more metadata lines
 # are added by future versions of the server, this won't cause problems,
 # since the only lines which appear in tINDEX.new are the ones which we
 # specifically grepped out of ${TINDEXHASH}.
 fetch_metadata_index_sanity () {
 	if grep -qvE '^[0-9A-Z.-]+\|[0-9a-f]{64}$' tINDEX.new; then
 		fetch_metadata_bogus " index"
 		return 1
 	fi
 }
 
 # Sanity check the metadata file $1.
 fetch_metadata_sanity () {
 	# Some aliases to save space later: ${P} is a character which can
 	# appear in a path; ${M} is the four numeric metadata fields; and
 	# ${H} is a sha256 hash.
 	P="[-+./:=,%@_[~[:alnum:]]"
 	M="[0-9]+\|[0-9]+\|[0-9]+\|[0-9]+"
 	H="[0-9a-f]{64}"
 
 	# Check that the first four fields make sense.
 	if gunzip -c < files/$1.gz |
 	    grep -qvE "^[a-z]+\|[0-9a-z-]+\|${P}+\|[fdL-]\|"; then
 		fetch_metadata_bogus ""
 		return 1
 	fi
 
 	# Remove the first three fields.
 	gunzip -c < files/$1.gz |
 	    cut -f 4- -d '|' > sanitycheck.tmp
 
 	# Sanity check entries with type 'f'
 	if grep -E '^f' sanitycheck.tmp |
 	    grep -qvE "^f\|${M}\|${H}\|${P}*\$"; then
 		fetch_metadata_bogus ""
 		return 1
 	fi
 
 	# Sanity check entries with type 'd'
 	if grep -E '^d' sanitycheck.tmp |
 	    grep -qvE "^d\|${M}\|\|\$"; then
 		fetch_metadata_bogus ""
 		return 1
 	fi
 
 	# Sanity check entries with type 'L'
 	if grep -E '^L' sanitycheck.tmp |
 	    grep -qvE "^L\|${M}\|${P}*\|\$"; then
 		fetch_metadata_bogus ""
 		return 1
 	fi
 
 	# Sanity check entries with type '-'
 	if grep -E '^-' sanitycheck.tmp |
 	    grep -qvE "^-\|\|\|\|\|\|"; then
 		fetch_metadata_bogus ""
 		return 1
 	fi
 
 	# Clean up
 	rm sanitycheck.tmp
 }
 
 # Fetch the metadata index and metadata files listed in $@,
 # taking advantage of metadata patches where possible.
 fetch_metadata () {
 	fetch_metadata_index || return 1
 	fetch_metadata_index_merge $@ || return 1
 	fetch_metadata_index_sanity || return 1
 
 	# Generate a list of wanted metadata patches
 	join -t '|' -o 1.2,2.2 tINDEX.present tINDEX.new |
 	    fetch_make_patchlist > patchlist
 
 	if [ -s patchlist ]; then
 		# Attempt to fetch metadata patches
 		echo -n "Fetching `wc -l < patchlist | tr -d ' '` "
 		echo ${NDEBUG} "metadata patches.${DDSTATS}"
 		tr '|' '-' < patchlist |
 		    lam -s "${FETCHDIR}/tp/" - -s ".gz" |
 		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
 			2>${STATSREDIR} | fetch_progress
 		echo "done."
 
 		# Attempt to apply metadata patches
 		echo -n "Applying metadata patches... "
 		tr '|' ' ' < patchlist |
 		    while read X Y; do
 			if [ ! -f "${X}-${Y}.gz" ]; then continue; fi
 			gunzip -c < ${X}-${Y}.gz > diff
 			gunzip -c < files/${X}.gz > diff-OLD
 
 			# Figure out which lines are being added and removed
 			grep -E '^-' diff |
 			    cut -c 2- |
 			    while read PREFIX; do
 				look "${PREFIX}" diff-OLD
 			    done |
 			    sort > diff-rm
 			grep -E '^\+' diff |
 			    cut -c 2- > diff-add
 
 			# Generate the new file
 			comm -23 diff-OLD diff-rm |
 			    sort - diff-add > diff-NEW
 
 			if [ `${SHA256} -q diff-NEW` = ${Y} ]; then
 				mv diff-NEW files/${Y}
 				gzip -n files/${Y}
 			else
 				mv diff-NEW ${Y}.bad
 			fi
 			rm -f ${X}-${Y}.gz diff
 			rm -f diff-OLD diff-NEW diff-add diff-rm
 		done 2>${QUIETREDIR}
 		echo "done."
 	fi
 
 	# Update metadata without patches
 	cut -f 2 -d '|' < tINDEX.new |
 	    while read Y; do
 		if [ ! -f "files/${Y}.gz" ]; then
 			echo ${Y};
 		fi
 	    done |
 	    sort -u > filelist
 
 	if [ -s filelist ]; then
 		echo -n "Fetching `wc -l < filelist | tr -d ' '` "
 		echo ${NDEBUG} "metadata files... "
 		lam -s "${FETCHDIR}/m/" - -s ".gz" < filelist |
 		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
 		    2>${QUIETREDIR}
 
 		while read Y; do
 			if ! [ -f ${Y}.gz ]; then
 				echo "failed."
 				return 1
 			fi
 			if [ `gunzip -c < ${Y}.gz |
 			    ${SHA256} -q` = ${Y} ]; then
 				mv ${Y}.gz files/${Y}.gz
 			else
 				echo "metadata is corrupt."
 				return 1
 			fi
 		done < filelist
 		echo "done."
 	fi
 
 # Sanity-check the metadata files.
 	cut -f 2 -d '|' tINDEX.new > filelist
 	while read X; do
 		fetch_metadata_sanity ${X} || return 1
 	done < filelist
 
 # Remove files which are no longer needed
 	cut -f 2 -d '|' tINDEX.present |
 	    sort > oldfiles
 	cut -f 2 -d '|' tINDEX.new |
 	    sort |
 	    comm -13 - oldfiles |
 	    lam -s "files/" - -s ".gz" |
 	    xargs rm -f
 	rm patchlist filelist oldfiles
 	rm ${TINDEXHASH}
 
 # We're done!
 	mv tINDEX.new tINDEX.present
 	mv tag.new tag
 
 	return 0
 }
 
 # Extract a subset of a downloaded metadata file containing only the parts
 # which are listed in COMPONENTS.
 fetch_filter_metadata_components () {
 	METAHASH=`look "$1|" tINDEX.present | cut -f 2 -d '|'`
 	gunzip -c < files/${METAHASH}.gz > $1.all
 
 	# Fish out the lines belonging to components we care about.
 	for C in ${COMPONENTS}; do
 		look "`echo ${C} | tr '/' '|'`|" $1.all
 	done > $1
 
 	# Remove temporary file.
 	rm $1.all
 }
 
 # Generate a filtered version of the metadata file $1 from the downloaded
 # file, by fishing out the lines corresponding to components we're trying
 # to keep updated, and then removing lines corresponding to paths we want
 # to ignore.
 fetch_filter_metadata () {
 	# Fish out the lines belonging to components we care about.
 	fetch_filter_metadata_components $1
 
 	# Canonicalize directory names by removing any trailing / in
 	# order to avoid listing directories multiple times if they
 	# belong to multiple components.  Turning "/" into "" doesn't
 	# matter, since we add a leading "/" when we use paths later.
 	cut -f 3- -d '|' $1 |
 	    sed -e 's,/|d|,|d|,' |
 	    sed -e 's,/|-|,|-|,' |
 	    sort -u > $1.tmp
 
 	# Figure out which lines to ignore and remove them.
 	for X in ${IGNOREPATHS}; do
 		grep -E "^${X}" $1.tmp
 	done |
 	    sort -u |
 	    comm -13 - $1.tmp > $1
 
 	# Remove temporary files.
 	rm $1.tmp
 }
 
 # Filter the metadata file $1 by adding lines with "/boot/$2"
 # replaced by ${KERNELDIR} (which is `sysctl -n kern.bootfile` minus the
 # trailing "/kernel"); and if "/boot/$2" does not exist, remove
 # the original lines which start with that.
 # Put another way: Deal with the fact that the FOO kernel is sometimes
 # installed in /boot/FOO/ and is sometimes installed elsewhere.
 fetch_filter_kernel_names () {
 	grep ^/boot/$2 $1 |
 	    sed -e "s,/boot/$2,${KERNELDIR},g" |
 	    sort - $1 > $1.tmp
 	mv $1.tmp $1
 
 	if ! [ -d /boot/$2 ]; then
 		grep -v ^/boot/$2 $1 > $1.tmp
 		mv $1.tmp $1
 	fi
 }
 
 # For all paths appearing in $1 or $3, inspect the system
 # and generate $2 describing what is currently installed.
 fetch_inspect_system () {
 	# No errors yet...
 	rm -f .err
 
 	# Tell the user why his disk is suddenly making lots of noise
 	echo -n "Inspecting system... "
 
 	# Generate list of files to inspect
 	cat $1 $3 |
 	    cut -f 1 -d '|' |
 	    sort -u > filelist
 
 	# Examine each file and output lines of the form
 	# /path/to/file|type|device-inum|user|group|perm|flags|value
 	# sorted by device and inode number.
 	while read F; do
 		# If the symlink/file/directory does not exist, record this.
 		if ! [ -e ${BASEDIR}/${F} ]; then
 			echo "${F}|-||||||"
 			continue
 		fi
 		if ! [ -r ${BASEDIR}/${F} ]; then
 			echo "Cannot read file: ${BASEDIR}/${F}"	\
 			    >/dev/stderr
 			touch .err
 			return 1
 		fi
 
 		# Otherwise, output an index line.
 		if [ -L ${BASEDIR}/${F} ]; then
 			echo -n "${F}|L|"
 			stat -n -f '%d-%i|%u|%g|%Mp%Lp|%Of|' ${BASEDIR}/${F};
 			readlink ${BASEDIR}/${F};
 		elif [ -f ${BASEDIR}/${F} ]; then
 			echo -n "${F}|f|"
 			stat -n -f '%d-%i|%u|%g|%Mp%Lp|%Of|' ${BASEDIR}/${F};
 			sha256 -q ${BASEDIR}/${F};
 		elif [ -d ${BASEDIR}/${F} ]; then
 			echo -n "${F}|d|"
 			stat -f '%d-%i|%u|%g|%Mp%Lp|%Of|' ${BASEDIR}/${F};
 		else
 			echo "Unknown file type: ${BASEDIR}/${F}"	\
 			    >/dev/stderr
 			touch .err
 			return 1
 		fi
 	done < filelist |
 	    sort -k 3,3 -t '|' > $2.tmp
 	rm filelist
 
 	# Check if an error occurred during system inspection
 	if [ -f .err ]; then
 		return 1
 	fi
 
 	# Convert to the form
 	# /path/to/file|type|user|group|perm|flags|value|hlink
 	# by resolving identical device and inode numbers into hard links.
 	cut -f 1,3 -d '|' $2.tmp |
 	    sort -k 1,1 -t '|' |
 	    sort -s -u -k 2,2 -t '|' |
 	    join -1 2 -2 3 -t '|' - $2.tmp |
 	    awk -F \| -v OFS=\|		\
 		'{
 		    if (($2 == $3) || ($4 == "-"))
 			print $3,$4,$5,$6,$7,$8,$9,""
 		    else
 			print $3,$4,$5,$6,$7,$8,$9,$2
 		}' |
 	    sort > $2
 	rm $2.tmp
 
 	# We're finished looking around
 	echo "done."
 }
 
 # For any paths matching ${MERGECHANGES}, compare $1 and $2 and find any
 # files which differ; generate $3 containing these paths and the old hashes.
 fetch_filter_mergechanges () {
 	# Pull out the paths and hashes of the files matching ${MERGECHANGES}.
 	for F in $1 $2; do
 		for X in ${MERGECHANGES}; do
 			grep -E "^${X}" ${F}
 		done |
 		    cut -f 1,2,7 -d '|' |
 		    sort > ${F}-values
 	done
 
 	# Any line in $2-values which doesn't appear in $1-values and is a
 	# file means that we should list the path in $3.
 	comm -13 $1-values $2-values |
 	    fgrep '|f|' |
 	    cut -f 1 -d '|' > $2-paths
 
 	# For each path, pull out one (and only one!) entry from $1-values.
 	# Note that we cannot distinguish which "old" version the user made
 	# changes to; but hopefully any changes which occur due to security
 	# updates will exist in both the "new" version and the version which
 	# the user has installed, so the merging will still work.
 	while read X; do
 		look "${X}|" $1-values |
 		    head -1
 	done < $2-paths > $3
 
 	# Clean up
 	rm $1-values $2-values $2-paths
 }
 
 # For any paths matching ${UPDATEIFUNMODIFIED}, remove lines from $[123]
 # which correspond to lines in $2 with hashes not matching $1 or $3, unless
 # the paths are listed in $4.  For entries in $2 marked "not present"
 # (aka. type -), remove lines from $[123] unless there is a corresponding
 # entry in $1.
 fetch_filter_unmodified_notpresent () {
 	# Figure out which lines of $1 and $3 correspond to bits which
 	# should only be updated if they haven't changed, and fish out
 	# the (path, type, value) tuples.
 	# NOTE: We don't consider a file to be "modified" if it matches
 	# the hash from $3.
 	for X in ${UPDATEIFUNMODIFIED}; do
 		grep -E "^${X}" $1
 		grep -E "^${X}" $3
 	done |
 	    cut -f 1,2,7 -d '|' |
 	    sort > $1-values
 
 	# Do the same for $2.
 	for X in ${UPDATEIFUNMODIFIED}; do
 		grep -E "^${X}" $2
 	done |
 	    cut -f 1,2,7 -d '|' |
 	    sort > $2-values
 
 	# Any entry in $2-values which is not in $1-values corresponds to
 	# a path which we need to remove from $1, $2, and $3, unless it
 	# that path appears in $4.
 	comm -13 $1-values $2-values |
 	    sort -t '|' -k 1,1 > mlines.tmp
 	cut -f 1 -d '|' $4 |
 	    sort |
 	    join -v 2 -t '|' - mlines.tmp |
 	    sort > mlines
 	rm $1-values $2-values mlines.tmp
 
 	# Any lines in $2 which are not in $1 AND are "not present" lines
 	# also belong in mlines.
 	comm -13 $1 $2 |
 	    cut -f 1,2,7 -d '|' |
 	    fgrep '|-|' >> mlines
 
 	# Remove lines from $1, $2, and $3
 	for X in $1 $2 $3; do
 		sort -t '|' -k 1,1 ${X} > ${X}.tmp
 		cut -f 1 -d '|' < mlines |
 		    sort |
 		    join -v 2 -t '|' - ${X}.tmp |
 		    sort > ${X}
 		rm ${X}.tmp
 	done
 
 	# Store a list of the modified files, for future reference
 	fgrep -v '|-|' mlines |
 	    cut -f 1 -d '|' > modifiedfiles
 	rm mlines
 }
 
 # For each entry in $1 of type -, remove any corresponding
 # entry from $2 if ${ALLOWADD} != "yes".  Remove all entries
 # of type - from $1.
 fetch_filter_allowadd () {
 	cut -f 1,2 -d '|' < $1 |
 	    fgrep '|-' |
 	    cut -f 1 -d '|' > filesnotpresent
 
 	if [ ${ALLOWADD} != "yes" ]; then
 		sort < $2 |
 		    join -v 1 -t '|' - filesnotpresent |
 		    sort > $2.tmp
 		mv $2.tmp $2
 	fi
 
 	sort < $1 |
 	    join -v 1 -t '|' - filesnotpresent |
 	    sort > $1.tmp
 	mv $1.tmp $1
 	rm filesnotpresent
 }
 
 # If ${ALLOWDELETE} != "yes", then remove any entries from $1
 # which don't correspond to entries in $2.
 fetch_filter_allowdelete () {
 	# Produce a lists ${PATH}|${TYPE}
 	for X in $1 $2; do
 		cut -f 1-2 -d '|' < ${X} |
 		    sort -u > ${X}.nodes
 	done
 
 	# Figure out which lines need to be removed from $1.
 	if [ ${ALLOWDELETE} != "yes" ]; then
 		comm -23 $1.nodes $2.nodes > $1.badnodes
 	else
 		: > $1.badnodes
 	fi
 
 	# Remove the relevant lines from $1
 	while read X; do
 		look "${X}|" $1
 	done < $1.badnodes |
 	    comm -13 - $1 > $1.tmp
 	mv $1.tmp $1
 
 	rm $1.badnodes $1.nodes $2.nodes
 }
 
 # If ${KEEPMODIFIEDMETADATA} == "yes", then for each entry in $2
 # with metadata not matching any entry in $1, replace the corresponding
 # line of $3 with one having the same metadata as the entry in $2.
 fetch_filter_modified_metadata () {
 	# Fish out the metadata from $1 and $2
 	for X in $1 $2; do
 		cut -f 1-6 -d '|' < ${X} > ${X}.metadata
 	done
 
 	# Find the metadata we need to keep
 	if [ ${KEEPMODIFIEDMETADATA} = "yes" ]; then
 		comm -13 $1.metadata $2.metadata > keepmeta
 	else
 		: > keepmeta
 	fi
 
 	# Extract the lines which we need to remove from $3, and
 	# construct the lines which we need to add to $3.
 	: > $3.remove
 	: > $3.add
 	while read LINE; do
 		NODE=`echo "${LINE}" | cut -f 1-2 -d '|'`
 		look "${NODE}|" $3 >> $3.remove
 		look "${NODE}|" $3 |
 		    cut -f 7- -d '|' |
 		    lam -s "${LINE}|" - >> $3.add
 	done < keepmeta
 
 	# Remove the specified lines and add the new lines.
 	sort $3.remove |
 	    comm -13 - $3 |
 	    sort -u - $3.add > $3.tmp
 	mv $3.tmp $3
 
 	rm keepmeta $1.metadata $2.metadata $3.add $3.remove
 }
 
 # Remove lines from $1 and $2 which are identical;
 # no need to update a file if it isn't changing.
 fetch_filter_uptodate () {
 	comm -23 $1 $2 > $1.tmp
 	comm -13 $1 $2 > $2.tmp
 
 	mv $1.tmp $1
 	mv $2.tmp $2
 }
 
 # Fetch any "clean" old versions of files we need for merging changes.
 fetch_files_premerge () {
 	# We only need to do anything if $1 is non-empty.
 	if [ -s $1 ]; then
 		# Tell the user what we're doing
 		echo -n "Fetching files from ${OLDRELNUM} for merging... "
 
 		# List of files wanted
 		fgrep '|f|' < $1 |
 		    cut -f 3 -d '|' |
 		    sort -u > files.wanted
 
 		# Only fetch the files we don't already have
 		while read Y; do
 			if [ ! -f "files/${Y}.gz" ]; then
 				echo ${Y};
 			fi
 		done < files.wanted > filelist
 
 		# Actually fetch them
 		lam -s "${OLDFETCHDIR}/f/" - -s ".gz" < filelist |
 		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
 		    2>${QUIETREDIR}
 
 		# Make sure we got them all, and move them into /files/
 		while read Y; do
 			if ! [ -f ${Y}.gz ]; then
 				echo "failed."
 				return 1
 			fi
 			if [ `gunzip -c < ${Y}.gz |
 			    ${SHA256} -q` = ${Y} ]; then
 				mv ${Y}.gz files/${Y}.gz
 			else
 				echo "${Y} has incorrect hash."
 				return 1
 			fi
 		done < filelist
 		echo "done."
 
 		# Clean up
 		rm filelist files.wanted
 	fi
 }
 
 # Prepare to fetch files: Generate a list of the files we need,
 # copy the unmodified files we have into /files/, and generate
 # a list of patches to download.
 fetch_files_prepare () {
 	# Tell the user why his disk is suddenly making lots of noise
 	echo -n "Preparing to download files... "
 
 	# Reduce indices to ${PATH}|${HASH} pairs
 	for X in $1 $2 $3; do
 		cut -f 1,2,7 -d '|' < ${X} |
 		    fgrep '|f|' |
 		    cut -f 1,3 -d '|' |
 		    sort > ${X}.hashes
 	done
 
 	# List of files wanted
 	cut -f 2 -d '|' < $3.hashes |
 	    sort -u |
 	    while read HASH; do
 		if ! [ -f files/${HASH}.gz ]; then
 			echo ${HASH}
 		fi
 	done > files.wanted
 
 	# Generate a list of unmodified files
 	comm -12 $1.hashes $2.hashes |
 	    sort -k 1,1 -t '|' > unmodified.files
 
 	# Copy all files into /files/.  We only need the unmodified files
 	# for use in patching; but we'll want all of them if the user asks
 	# to rollback the updates later.
 	while read LINE; do
 		F=`echo "${LINE}" | cut -f 1 -d '|'`
 		HASH=`echo "${LINE}" | cut -f 2 -d '|'`
 
 		# Skip files we already have.
 		if [ -f files/${HASH}.gz ]; then
 			continue
 		fi
 
 		# Make sure the file hasn't changed.
 		cp "${BASEDIR}/${F}" tmpfile
 		if [ `sha256 -q tmpfile` != ${HASH} ]; then
 			echo
 			echo "File changed while FreeBSD Update running: ${F}"
 			return 1
 		fi
 
 		# Place the file into storage.
 		gzip -c < tmpfile > files/${HASH}.gz
 		rm tmpfile
 	done < $2.hashes
 
 	# Produce a list of patches to download
 	sort -k 1,1 -t '|' $3.hashes |
 	    join -t '|' -o 2.2,1.2 - unmodified.files |
 	    fetch_make_patchlist > patchlist
 
 	# Garbage collect
 	rm unmodified.files $1.hashes $2.hashes $3.hashes
 
 	# We don't need the list of possible old files any more.
 	rm $1
 
 	# We're finished making noise
 	echo "done."
 }
 
 # Fetch files.
 fetch_files () {
 	# Attempt to fetch patches
 	if [ -s patchlist ]; then
 		echo -n "Fetching `wc -l < patchlist | tr -d ' '` "
 		echo ${NDEBUG} "patches.${DDSTATS}"
 		tr '|' '-' < patchlist |
 		    lam -s "${PATCHDIR}/" - |
 		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
 			2>${STATSREDIR} | fetch_progress
 		echo "done."
 
 		# Attempt to apply patches
 		echo -n "Applying patches... "
 		tr '|' ' ' < patchlist |
 		    while read X Y; do
 			if [ ! -f "${X}-${Y}" ]; then continue; fi
 			gunzip -c < files/${X}.gz > OLD
 
 			bspatch OLD NEW ${X}-${Y}
 
 			if [ `${SHA256} -q NEW` = ${Y} ]; then
 				mv NEW files/${Y}
 				gzip -n files/${Y}
 			fi
 			rm -f diff OLD NEW ${X}-${Y}
 		done 2>${QUIETREDIR}
 		echo "done."
 	fi
 
 	# Download files which couldn't be generate via patching
 	while read Y; do
 		if [ ! -f "files/${Y}.gz" ]; then
 			echo ${Y};
 		fi
 	done < files.wanted > filelist
 
 	if [ -s filelist ]; then
 		echo -n "Fetching `wc -l < filelist | tr -d ' '` "
 		echo ${NDEBUG} "files... "
 		lam -s "${FETCHDIR}/f/" - -s ".gz" < filelist |
 		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
 			2>${STATSREDIR} | fetch_progress
 
 		while read Y; do
 			if ! [ -f ${Y}.gz ]; then
 				echo "failed."
 				return 1
 			fi
 			if [ `gunzip -c < ${Y}.gz |
 			    ${SHA256} -q` = ${Y} ]; then
 				mv ${Y}.gz files/${Y}.gz
 			else
 				echo "${Y} has incorrect hash."
 				return 1
 			fi
 		done < filelist
 		echo "done."
 	fi
 
 	# Clean up
 	rm files.wanted filelist patchlist
 }
 
 # Create and populate install manifest directory; and report what updates
 # are available.
 fetch_create_manifest () {
 	# If we have an existing install manifest, nuke it.
 	if [ -L "${BDHASH}-install" ]; then
 		rm -r ${BDHASH}-install/
 		rm ${BDHASH}-install
 	fi
 
 	# Report to the user if any updates were avoided due to local changes
 	if [ -s modifiedfiles ]; then
 		cat - modifiedfiles <<- EOF | ${PAGER}
 			The folling files are affected by updates but no changes have
 			been downloaded because the files have been modified locally:
 		EOF
 	fi
 	rm modifiedfiles
 
 	# If no files will be updated, tell the user and exit
 	if ! [ -s INDEX-PRESENT ] &&
 	    ! [ -s INDEX-NEW ]; then
 		rm INDEX-PRESENT INDEX-NEW
 		echo
 		echo -n "No updates needed to update system to "
 		echo "${RELNUM}-p${RELPATCHNUM}."
 		return
 	fi
 
 	# Divide files into (a) removed files, (b) added files, and
 	# (c) updated files.
 	cut -f 1 -d '|' < INDEX-PRESENT |
 	    sort > INDEX-PRESENT.flist
 	cut -f 1 -d '|' < INDEX-NEW |
 	    sort > INDEX-NEW.flist
 	comm -23 INDEX-PRESENT.flist INDEX-NEW.flist > files.removed
 	comm -13 INDEX-PRESENT.flist INDEX-NEW.flist > files.added
 	comm -12 INDEX-PRESENT.flist INDEX-NEW.flist > files.updated
 	rm INDEX-PRESENT.flist INDEX-NEW.flist
 
 	# Report removed files, if any
 	if [ -s files.removed ]; then
 		cat - files.removed <<- EOF | ${PAGER}
 			The following files will be removed as part of updating to
 			${RELNUM}-p${RELPATCHNUM}:
 		EOF
 	fi
 	rm files.removed
 
 	# Report added files, if any
 	if [ -s files.added ]; then
 		cat - files.added <<- EOF | ${PAGER}
 			The following files will be added as part of updating to
 			${RELNUM}-p${RELPATCHNUM}:
 		EOF
 	fi
 	rm files.added
 
 	# Report updated files, if any
 	if [ -s files.updated ]; then
 		cat - files.updated <<- EOF | ${PAGER}
 			The following files will be updated as part of updating to
 			${RELNUM}-p${RELPATCHNUM}:
 		EOF
 	fi
 	rm files.updated
 
 	# Create a directory for the install manifest.
 	MDIR=`mktemp -d install.XXXXXX` || return 1
 
 	# Populate it
 	mv INDEX-PRESENT ${MDIR}/INDEX-OLD
 	mv INDEX-NEW ${MDIR}/INDEX-NEW
 
 	# Link it into place
 	ln -s ${MDIR} ${BDHASH}-install
 }
 
 # Warn about any upcoming EoL
 fetch_warn_eol () {
 	# What's the current time?
 	NOWTIME=`date "+%s"`
 
 	# When did we last warn about the EoL date?
 	if [ -f lasteolwarn ]; then
 		LASTWARN=`cat lasteolwarn`
 	else
 		LASTWARN=`expr ${NOWTIME} - 63072000`
 	fi
 
 	# If the EoL time is past, warn.
 	if [ ${EOLTIME} -lt ${NOWTIME} ]; then
 		echo
 		cat <<-EOF
 		WARNING: `uname -sr` HAS PASSED ITS END-OF-LIFE DATE.
 		Any security issues discovered after `date -r ${EOLTIME}`
 		will not have been corrected.
 		EOF
 		return 1
 	fi
 
 	# Figure out how long it has been since we last warned about the
 	# upcoming EoL, and how much longer we have left.
 	SINCEWARN=`expr ${NOWTIME} - ${LASTWARN}`
 	TIMELEFT=`expr ${EOLTIME} - ${NOWTIME}`
 
 	# Don't warn if the EoL is more than 3 months away
 	if [ ${TIMELEFT} -gt 7884000 ]; then
 		return 0
 	fi
 
 	# Don't warn if the time remaining is more than 3 times the time
 	# since the last warning.
 	if [ ${TIMELEFT} -gt `expr ${SINCEWARN} \* 3` ]; then
 		return 0
 	fi
 
 	# Figure out what time units to use.
 	if [ ${TIMELEFT} -lt 604800 ]; then
 		UNIT="day"
 		SIZE=86400
 	elif [ ${TIMELEFT} -lt 2678400 ]; then
 		UNIT="week"
 		SIZE=604800
 	else
 		UNIT="month"
 		SIZE=2678400
 	fi
 
 	# Compute the right number of units
 	NUM=`expr ${TIMELEFT} / ${SIZE}`
 	if [ ${NUM} != 1 ]; then
 		UNIT="${UNIT}s"
 	fi
 
 	# Print the warning
 	echo
 	cat <<-EOF
 		WARNING: `uname -sr` is approaching its End-of-Life date.
 		It is strongly recommended that you upgrade to a newer
 		release within the next ${NUM} ${UNIT}.
 	EOF
 
 	# Update the stored time of last warning
 	echo ${NOWTIME} > lasteolwarn
 }
 
 # Do the actual work involved in "fetch" / "cron".
 fetch_run () {
 	workdir_init || return 1
 
 	# Prepare the mirror list.
 	fetch_pick_server_init && fetch_pick_server
 
 	# Try to fetch the public key until we run out of servers.
 	while ! fetch_key; do
 		fetch_pick_server || return 1
 	done
 
 	# Try to fetch the metadata index signature ("tag") until we run
 	# out of available servers; and sanity check the downloaded tag.
 	while ! fetch_tag; do
 		fetch_pick_server || return 1
 	done
 	fetch_tagsanity || return 1
 
 	# Fetch the latest INDEX-NEW and INDEX-OLD files.
 	fetch_metadata INDEX-NEW INDEX-OLD || return 1
 
 	# Generate filtered INDEX-NEW and INDEX-OLD files containing only
 	# the lines which (a) belong to components we care about, and (b)
 	# don't correspond to paths we're explicitly ignoring.
 	fetch_filter_metadata INDEX-NEW || return 1
 	fetch_filter_metadata INDEX-OLD || return 1
 
 	# Translate /boot/${KERNCONF} into ${KERNELDIR}
 	fetch_filter_kernel_names INDEX-NEW ${KERNCONF}
 	fetch_filter_kernel_names INDEX-OLD ${KERNCONF}
 
 	# For all paths appearing in INDEX-OLD or INDEX-NEW, inspect the
 	# system and generate an INDEX-PRESENT file.
 	fetch_inspect_system INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1
 
 	# Based on ${UPDATEIFUNMODIFIED}, remove lines from INDEX-* which
 	# correspond to lines in INDEX-PRESENT with hashes not appearing
 	# in INDEX-OLD or INDEX-NEW.  Also remove lines where the entry in
 	# INDEX-PRESENT has type - and there isn't a corresponding entry in
 	# INDEX-OLD with type -.
 	fetch_filter_unmodified_notpresent	\
 	    INDEX-OLD INDEX-PRESENT INDEX-NEW /dev/null
 
 	# For each entry in INDEX-PRESENT of type -, remove any corresponding
 	# entry from INDEX-NEW if ${ALLOWADD} != "yes".  Remove all entries
 	# of type - from INDEX-PRESENT.
 	fetch_filter_allowadd INDEX-PRESENT INDEX-NEW
 
 	# If ${ALLOWDELETE} != "yes", then remove any entries from
 	# INDEX-PRESENT which don't correspond to entries in INDEX-NEW.
 	fetch_filter_allowdelete INDEX-PRESENT INDEX-NEW
 
 	# If ${KEEPMODIFIEDMETADATA} == "yes", then for each entry in
 	# INDEX-PRESENT with metadata not matching any entry in INDEX-OLD,
 	# replace the corresponding line of INDEX-NEW with one having the
 	# same metadata as the entry in INDEX-PRESENT.
 	fetch_filter_modified_metadata INDEX-OLD INDEX-PRESENT INDEX-NEW
 
 	# Remove lines from INDEX-PRESENT and INDEX-NEW which are identical;
 	# no need to update a file if it isn't changing.
 	fetch_filter_uptodate INDEX-PRESENT INDEX-NEW
 
 	# Prepare to fetch files: Generate a list of the files we need,
 	# copy the unmodified files we have into /files/, and generate
 	# a list of patches to download.
 	fetch_files_prepare INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1
 
 	# Fetch files.
 	fetch_files || return 1
 
 	# Create and populate install manifest directory; and report what
 	# updates are available.
 	fetch_create_manifest || return 1
 
 	# Warn about any upcoming EoL
 	fetch_warn_eol || return 1
 }
 
 # If StrictComponents is not "yes", generate a new components list
 # with only the components which appear to be installed.
 upgrade_guess_components () {
 	if [ "${STRICTCOMPONENTS}" = "no" ]; then
 		# Generate filtered INDEX-ALL with only the components listed
 		# in COMPONENTS.
 		fetch_filter_metadata_components $1 || return 1
 
 		# Tell the user why his disk is suddenly making lots of noise
 		echo -n "Inspecting system... "
 
 		# Look at the files on disk, and assume that a component is
 		# supposed to be present if it is more than half-present.
 		cut -f 1-3 -d '|' < INDEX-ALL |
 		    tr '|' ' ' |
 		    while read C S F; do
 			if [ -e ${BASEDIR}/${F} ]; then
 				echo "+ ${C}|${S}"
 			fi
 			echo "= ${C}|${S}"
 		    done |
 		    sort |
 		    uniq -c |
 		    sed -E 's,^ +,,' > compfreq
 		grep ' = ' compfreq |
 		    cut -f 1,3 -d ' ' |
 		    sort -k 2,2 -t ' ' > compfreq.total
 		grep ' + ' compfreq |
 		    cut -f 1,3 -d ' ' |
 		    sort -k 2,2 -t ' ' > compfreq.present
 		join -t ' ' -1 2 -2 2 compfreq.present compfreq.total |
 		    while read S P T; do
 			if [ ${T} -ne 0 -a ${P} -gt `expr ${T} / 2` ]; then
 				echo ${S}
 			fi
 		    done > comp.present
 		cut -f 2 -d ' ' < compfreq.total > comp.total
 		rm INDEX-ALL compfreq compfreq.total compfreq.present
 
 		# We're done making noise.
 		echo "done."
 
 		# Sometimes the kernel isn't installed where INDEX-ALL
 		# thinks that it should be: In particular, it is often in
 		# /boot/kernel instead of /boot/GENERIC or /boot/SMP.  To
 		# deal with this, if "kernel|X" is listed in comp.total
 		# (i.e., is a component which would be upgraded if it is
 		# found to be present) we will add it to comp.present.
 		# If "kernel|<anything>" is in comp.total but "kernel|X" is
 		# not, we print a warning -- the user is running a kernel
 		# which isn't part of the release.
 		KCOMP=`echo ${KERNCONF} | tr 'A-Z' 'a-z'`
 		grep -E "^kernel\|${KCOMP}\$" comp.total >> comp.present
 
 		if grep -qE "^kernel\|" comp.total &&
 		    ! grep -qE "^kernel\|${KCOMP}\$" comp.total; then
 			cat <<-EOF
 
 WARNING: This system is running a "${KCOMP}" kernel, which is not a
 kernel configuration distributed as part of FreeBSD ${RELNUM}.
 This kernel will not be updated: you MUST update the kernel manually
 before running "$0 install".
 			EOF
 		fi
 
 		# Re-sort the list of installed components and generate
 		# the list of non-installed components.
 		sort -u < comp.present > comp.present.tmp
 		mv comp.present.tmp comp.present
 		comm -13 comp.present comp.total > comp.absent
 
 		# Ask the user to confirm that what we have is correct.  To
 		# reduce user confusion, translate "X|Y" back to "X/Y" (as
 		# subcomponents must be listed in the configuration file).
 		echo
 		echo -n "The following components of FreeBSD "
 		echo "seem to be installed:"
 		tr '|' '/' < comp.present |
 		    fmt -72
 		echo
 		echo -n "The following components of FreeBSD "
 		echo "do not seem to be installed:"
 		tr '|' '/' < comp.absent |
 		    fmt -72
 		echo
 		continuep || return 1
 		echo
 
 		# Suck the generated list of components into ${COMPONENTS}.
 		# Note that comp.present.tmp is used due to issues with
 		# pipelines and setting variables.
 		COMPONENTS=""
 		tr '|' '/' < comp.present > comp.present.tmp
 		while read C; do
 			COMPONENTS="${COMPONENTS} ${C}"
 		done < comp.present.tmp
 
 		# Delete temporary files
 		rm comp.present comp.present.tmp comp.absent comp.total
 	fi
 }
 
 # If StrictComponents is not "yes", COMPONENTS contains an entry
 # corresponding to the currently running kernel, and said kernel
 # does not exist in the new release, add "kernel/generic" to the
 # list of components.
 upgrade_guess_new_kernel () {
 	if [ "${STRICTCOMPONENTS}" = "no" ]; then
 		# Grab the unfiltered metadata file.
 		METAHASH=`look "$1|" tINDEX.present | cut -f 2 -d '|'`
 		gunzip -c < files/${METAHASH}.gz > $1.all
 
 		# If "kernel/${KCOMP}" is in ${COMPONENTS} and that component
 		# isn't in $1.all, we need to add kernel/generic.
 		for C in ${COMPONENTS}; do
 			if [ ${C} = "kernel/${KCOMP}" ] &&
 			    ! grep -qE "^kernel\|${KCOMP}\|" $1.all; then
 				COMPONENTS="${COMPONENTS} kernel/generic"
 				NKERNCONF="GENERIC"
 				cat <<-EOF
 
 WARNING: This system is running a "${KCOMP}" kernel, which is not a
 kernel configuration distributed as part of FreeBSD ${RELNUM}.
 As part of upgrading to FreeBSD ${RELNUM}, this kernel will be
 replaced with a "generic" kernel.
 				EOF
 				continuep || return 1
 			fi
 		done
 
 		# Don't need this any more...
 		rm $1.all
 	fi
 }
 
 # Convert INDEX-OLD (last release) and INDEX-ALL (new release) into
 # INDEX-OLD and INDEX-NEW files (in the sense of normal upgrades).
 upgrade_oldall_to_oldnew () {
 	# For each ${F}|... which appears in INDEX-ALL but does not appear
 	# in INDEX-OLD, add ${F}|-|||||| to INDEX-OLD.
 	cut -f 1 -d '|' < $1 |
 	    sort -u > $1.paths
 	cut -f 1 -d '|' < $2 |
 	    sort -u |
 	    comm -13 $1.paths - |
 	    lam - -s "|-||||||" |
 	    sort - $1 > $1.tmp
 	mv $1.tmp $1
 
 	# Remove lines from INDEX-OLD which also appear in INDEX-ALL
 	comm -23 $1 $2 > $1.tmp
 	mv $1.tmp $1
 
 	# Remove lines from INDEX-ALL which have a file name not appearing
 	# anywhere in INDEX-OLD (since these must be files which haven't
 	# changed -- if they were new, there would be an entry of type "-").
 	cut -f 1 -d '|' < $1 |
 	    sort -u > $1.paths
 	sort -k 1,1 -t '|' < $2 |
 	    join -t '|' - $1.paths |
 	    sort > $2.tmp
 	rm $1.paths
 	mv $2.tmp $2
 
 	# Rename INDEX-ALL to INDEX-NEW.
 	mv $2 $3
 }
 
 # Helper for upgrade_merge: Return zero true iff the two files differ only
 # in the contents of their RCS tags.
 samef () {
 	X=`sed -E 's/\\$FreeBSD.*\\$/\$FreeBSD\$/' < $1 | ${SHA256}`
 	Y=`sed -E 's/\\$FreeBSD.*\\$/\$FreeBSD\$/' < $2 | ${SHA256}`
 
 	if [ $X = $Y ]; then
 		return 0;
 	else
 		return 1;
 	fi
 }
 
 # From the list of "old" files in $1, merge changes in $2 with those in $3,
 # and update $3 to reflect the hashes of merged files.
 upgrade_merge () {
 	# We only need to do anything if $1 is non-empty.
 	if [ -s $1 ]; then
 		cut -f 1 -d '|' $1 |
 		    sort > $1-paths
 
 		# Create staging area for merging files
 		rm -rf merge/
 		while read F; do
 			D=`dirname ${F}`
 			mkdir -p merge/old/${D}
 			mkdir -p merge/${OLDRELNUM}/${D}
 			mkdir -p merge/${RELNUM}/${D}
 			mkdir -p merge/new/${D}
 		done < $1-paths
 
 		# Copy in files
 		while read F; do
 			# Currently installed file
 			V=`look "${F}|" $2 | cut -f 7 -d '|'`
 			gunzip < files/${V}.gz > merge/old/${F}
 
 			# Old release
 			if look "${F}|" $1 | fgrep -q "|f|"; then
 				V=`look "${F}|" $1 | cut -f 3 -d '|'`
 				gunzip < files/${V}.gz		\
 				    > merge/${OLDRELNUM}/${F}
 			fi
 
 			# New release
 			if look "${F}|" $3 | cut -f 1,2,7 -d '|' |
 			    fgrep -q "|f|"; then
 				V=`look "${F}|" $3 | cut -f 7 -d '|'`
 				gunzip < files/${V}.gz		\
 				    > merge/${RELNUM}/${F}
 			fi
 		done < $1-paths
 
 		# Attempt to automatically merge changes
 		echo -n "Attempting to automatically merge "
 		echo -n "changes in files..."
 		: > failed.merges
 		while read F; do
 			# If the file doesn't exist in the new release,
 			# the result of "merging changes" is having the file
 			# not exist.
 			if ! [ -f merge/${RELNUM}/${F} ]; then
 				continue
 			fi
 
 			# If the file didn't exist in the old release, we're
 			# going to throw away the existing file and hope that
 			# the version from the new release is what we want.
 			if ! [ -f merge/${OLDRELNUM}/${F} ]; then
 				cp merge/${RELNUM}/${F} merge/new/${F}
 				continue
 			fi
 
 			# Some files need special treatment.
 			case ${F} in
 			/etc/spwd.db | /etc/pwd.db | /etc/login.conf.db)
 				# Don't merge these -- we're rebuild them
 				# after updates are installed.
 				cp merge/old/${F} merge/new/${F}
 				;;
 			*)
 				if ! diff3 -E -m -L "current version"	\
 				    -L "${OLDRELNUM}" -L "${RELNUM}"	\
 				    merge/old/${F}			\
 				    merge/${OLDRELNUM}/${F}		\
 				    merge/${RELNUM}/${F}		\
 				    > merge/new/${F} 2>/dev/null; then
 					echo ${F} >> failed.merges
 				fi
 				;;
 			esac
 		done < $1-paths
 		echo " done."
 
 		# Ask the user to handle any files which didn't merge.
 		while read F; do
 			# If the installed file differs from the version in
 			# the old release only due to RCS tag expansion
 			# then just use the version in the new release.
 			if samef merge/old/${F} merge/${OLDRELNUM}/${F}; then
 				cp merge/${RELNUM}/${F} merge/new/${F}
 				continue
 			fi
 
 			cat <<-EOF
 
 The following file could not be merged automatically: ${F}
 Press Enter to edit this file in ${EDITOR} and resolve the conflicts
 manually...
 			EOF
 			read dummy </dev/tty
 			${EDITOR} `pwd`/merge/new/${F} < /dev/tty
 		done < failed.merges
 		rm failed.merges
 
 		# Ask the user to confirm that he likes how the result
 		# of merging files.
 		while read F; do
 			# Skip files which haven't changed except possibly
 			# in their RCS tags.
 			if [ -f merge/old/${F} ] && [ -f merge/new/${F} ] &&
 			    samef merge/old/${F} merge/new/${F}; then
 				continue
 			fi
 
 			# Skip files where the installed file differs from
 			# the old file only due to RCS tags.
 			if [ -f merge/old/${F} ] &&
 			    [ -f merge/${OLDRELNUM}/${F} ] &&
 			    samef merge/old/${F} merge/${OLDRELNUM}/${F}; then
 				continue
 			fi
 
 			# Warn about files which are ceasing to exist.
 			if ! [ -f merge/new/${F} ]; then
 				cat <<-EOF
 
 The following file will be removed, as it no longer exists in
 FreeBSD ${RELNUM}: ${F}
 				EOF
 				continuep < /dev/tty || return 1
 				continue
 			fi
 
 			# Print changes for the user's approval.
 			cat <<-EOF
 
 The following changes, which occurred between FreeBSD ${OLDRELNUM} and
 FreeBSD ${RELNUM} have been merged into ${F}:
 EOF
 			diff -U 5 -L "current version" -L "new version"	\
 			    merge/old/${F} merge/new/${F} || true
 			continuep < /dev/tty || return 1
 		done < $1-paths
 
 		# Store merged files.
 		while read F; do
 			if [ -f merge/new/${F} ]; then
 				V=`${SHA256} -q merge/new/${F}`
 
 				gzip -c < merge/new/${F} > files/${V}.gz
 				echo "${F}|${V}"
 			fi
 		done < $1-paths > newhashes
 
 		# Pull lines out from $3 which need to be updated to
 		# reflect merged files.
 		while read F; do
 			look "${F}|" $3
 		done < $1-paths > $3-oldlines
 
 		# Update lines to reflect merged files
 		join -t '|' -o 1.1,1.2,1.3,1.4,1.5,1.6,2.2,1.8		\
 		    $3-oldlines newhashes > $3-newlines
 
 		# Remove old lines from $3 and add new lines.
 		sort $3-oldlines |
 		    comm -13 - $3 |
 		    sort - $3-newlines > $3.tmp
 		mv $3.tmp $3
 
 		# Clean up
 		rm $1-paths newhashes $3-oldlines $3-newlines
 		rm -rf merge/
 	fi
 
 	# We're done with merging files.
 	rm $1
 }
 
 # Do the work involved in fetching upgrades to a new release
 upgrade_run () {
 	workdir_init || return 1
 
 	# Prepare the mirror list.
 	fetch_pick_server_init && fetch_pick_server
 
 	# Try to fetch the public key until we run out of servers.
 	while ! fetch_key; do
 		fetch_pick_server || return 1
 	done
  
 	# Try to fetch the metadata index signature ("tag") until we run
 	# out of available servers; and sanity check the downloaded tag.
 	while ! fetch_tag; do
 		fetch_pick_server || return 1
 	done
 	fetch_tagsanity || return 1
 
 	# Fetch the INDEX-OLD and INDEX-ALL.
 	fetch_metadata INDEX-OLD INDEX-ALL || return 1
 
 	# If StrictComponents is not "yes", generate a new components list
 	# with only the components which appear to be installed.
 	upgrade_guess_components INDEX-ALL || return 1
 
 	# Generate filtered INDEX-OLD and INDEX-ALL files containing only
 	# the components we want and without anything marked as "Ignore".
 	fetch_filter_metadata INDEX-OLD || return 1
 	fetch_filter_metadata INDEX-ALL || return 1
 
 	# Merge the INDEX-OLD and INDEX-ALL files into INDEX-OLD.
 	sort INDEX-OLD INDEX-ALL > INDEX-OLD.tmp
 	mv INDEX-OLD.tmp INDEX-OLD
 	rm INDEX-ALL
 
 	# Adjust variables for fetching files from the new release.
 	OLDRELNUM=${RELNUM}
 	RELNUM=${TARGETRELEASE}
 	OLDFETCHDIR=${FETCHDIR}
 	FETCHDIR=${RELNUM}/${ARCH}
 
 	# Try to fetch the NEW metadata index signature ("tag") until we run
 	# out of available servers; and sanity check the downloaded tag.
 	while ! fetch_tag; do
 		fetch_pick_server || return 1
 	done
 
 	# Fetch the new INDEX-ALL.
 	fetch_metadata INDEX-ALL || return 1
 
 	# If StrictComponents is not "yes", COMPONENTS contains an entry
 	# corresponding to the currently running kernel, and said kernel
 	# does not exist in the new release, add "kernel/generic" to the
 	# list of components.
 	upgrade_guess_new_kernel INDEX-ALL || return 1
 
 	# Filter INDEX-ALL to contain only the components we want and without
 	# anything marked as "Ignore".
 	fetch_filter_metadata INDEX-ALL || return 1
 
 	# Convert INDEX-OLD (last release) and INDEX-ALL (new release) into
 	# INDEX-OLD and INDEX-NEW files (in the sense of normal upgrades).
 	upgrade_oldall_to_oldnew INDEX-OLD INDEX-ALL INDEX-NEW
 
 	# Translate /boot/${KERNCONF} or /boot/${NKERNCONF} into ${KERNELDIR}
 	fetch_filter_kernel_names INDEX-NEW ${NKERNCONF}
 	fetch_filter_kernel_names INDEX-OLD ${KERNCONF}
 
 	# For all paths appearing in INDEX-OLD or INDEX-NEW, inspect the
 	# system and generate an INDEX-PRESENT file.
 	fetch_inspect_system INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1
 
 	# Based on ${MERGECHANGES}, generate a file tomerge-old with the
 	# paths and hashes of old versions of files to merge.
 	fetch_filter_mergechanges INDEX-OLD INDEX-PRESENT tomerge-old
 
 	# Based on ${UPDATEIFUNMODIFIED}, remove lines from INDEX-* which
 	# correspond to lines in INDEX-PRESENT with hashes not appearing
 	# in INDEX-OLD or INDEX-NEW.  Also remove lines where the entry in
 	# INDEX-PRESENT has type - and there isn't a corresponding entry in
 	# INDEX-OLD with type -.
 	fetch_filter_unmodified_notpresent	\
 	    INDEX-OLD INDEX-PRESENT INDEX-NEW tomerge-old
 
 	# For each entry in INDEX-PRESENT of type -, remove any corresponding
 	# entry from INDEX-NEW if ${ALLOWADD} != "yes".  Remove all entries
 	# of type - from INDEX-PRESENT.
 	fetch_filter_allowadd INDEX-PRESENT INDEX-NEW
 
 	# If ${ALLOWDELETE} != "yes", then remove any entries from
 	# INDEX-PRESENT which don't correspond to entries in INDEX-NEW.
 	fetch_filter_allowdelete INDEX-PRESENT INDEX-NEW
 
 	# If ${KEEPMODIFIEDMETADATA} == "yes", then for each entry in
 	# INDEX-PRESENT with metadata not matching any entry in INDEX-OLD,
 	# replace the corresponding line of INDEX-NEW with one having the
 	# same metadata as the entry in INDEX-PRESENT.
 	fetch_filter_modified_metadata INDEX-OLD INDEX-PRESENT INDEX-NEW
 
 	# Remove lines from INDEX-PRESENT and INDEX-NEW which are identical;
 	# no need to update a file if it isn't changing.
 	fetch_filter_uptodate INDEX-PRESENT INDEX-NEW
 
 	# Fetch "clean" files from the old release for merging changes.
 	fetch_files_premerge tomerge-old
 
 	# Prepare to fetch files: Generate a list of the files we need,
 	# copy the unmodified files we have into /files/, and generate
 	# a list of patches to download.
 	fetch_files_prepare INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1
 
 	# Fetch patches from to-${RELNUM}/${ARCH}/bp/
 	PATCHDIR=to-${RELNUM}/${ARCH}/bp
 	fetch_files || return 1
 
 	# Merge configuration file changes.
 	upgrade_merge tomerge-old INDEX-PRESENT INDEX-NEW || return 1
 
 	# Create and populate install manifest directory; and report what
 	# updates are available.
 	fetch_create_manifest || return 1
 
 	# Leave a note behind to tell the "install" command that the kernel
 	# needs to be installed before the world.
 	touch ${BDHASH}-install/kernelfirst
 
 	# Remind the user that they need to run "freebsd-update install"
 	# to install the downloaded bits, in case they didn't RTFM.
 	echo "To install the downloaded upgrades, run \"$0 install\"."
 }
 
 # Make sure that all the file hashes mentioned in $@ have corresponding
 # gzipped files stored in /files/.
 install_verify () {
 	# Generate a list of hashes
 	cat $@ |
 	    cut -f 2,7 -d '|' |
 	    grep -E '^f' |
 	    cut -f 2 -d '|' |
 	    sort -u > filelist
 
 	# Make sure all the hashes exist
 	while read HASH; do
 		if ! [ -f files/${HASH}.gz ]; then
 			echo -n "Update files missing -- "
 			echo "this should never happen."
 			echo "Re-run '$0 fetch'."
 			return 1
 		fi
 	done < filelist
 
 	# Clean up
 	rm filelist
 }
 
 # Remove the system immutable flag from files
 install_unschg () {
 	# Generate file list
 	cat $@ |
 	    cut -f 1 -d '|' > filelist
 
 	# Remove flags
 	while read F; do
 		if ! [ -e ${BASEDIR}/${F} ]; then
 			continue
 		else
 			echo ${BASEDIR}/${F}
 		fi
 	done < filelist | xargs chflags noschg || return 1
 
 	# Clean up
 	rm filelist
 }
 
 # Decide which directory name to use for kernel backups.
 backup_kernel_finddir () {
 	CNT=0
 	while true ; do
 		# Pathname does not exist, so it is OK use that name
 		# for backup directory.
 		if [ ! -e $BASEDIR/$BACKUPKERNELDIR ]; then
 			return 0
 		fi
 
 		# If directory do exist, we only use if it has our
 		# marker file.
 		if [ -d $BASEDIR/$BACKUPKERNELDIR -a \
 			-e $BASEDIR/$BACKUPKERNELDIR/.freebsd-update ]; then
 			return 0
 		fi
 
 		# We could not use current directory name, so add counter to
 		# the end and try again.
 		CNT=$((CNT + 1))
 		if [ $CNT -gt 9 ]; then
 			echo "Could not find valid backup dir ($BASEDIR/$BACKUPKERNELDIR)"
 			exit 1
 		fi
 		BACKUPKERNELDIR="`echo $BACKUPKERNELDIR | sed -Ee 's/[0-9]\$//'`"
 		BACKUPKERNELDIR="${BACKUPKERNELDIR}${CNT}"
 	done
 }
 
 # Backup the current kernel using hardlinks, if not disabled by user.
 # Since we delete all files in the directory used for previous backups
 # we create a marker file called ".freebsd-update" in the directory so
 # we can determine on the next run that the directory was created by
 # freebsd-update and we then do not accidentally remove user files in
 # the unlikely case that the user has created a directory with a
 # conflicting name.
 backup_kernel () {
 	# Only make kernel backup is so configured.
 	if [ $BACKUPKERNEL != yes ]; then
 		return 0
 	fi
 
 	# Decide which directory name to use for kernel backups.
 	backup_kernel_finddir
 
 	# Remove old kernel backup files.  If $BACKUPKERNELDIR was
 	# "not ours", backup_kernel_finddir would have exited, so
 	# deleting the directory content is as safe as we can make it.
 	if [ -d $BASEDIR/$BACKUPKERNELDIR ]; then
 		rm -fr $BASEDIR/$BACKUPKERNELDIR
 	fi
 
 	# Create directories for backup.
 	mkdir -p $BASEDIR/$BACKUPKERNELDIR
 	mtree -cdn -p "${BASEDIR}/${KERNELDIR}" | \
 	    mtree -Ue -p "${BASEDIR}/${BACKUPKERNELDIR}" > /dev/null
 
 	# Mark the directory as having been created by freebsd-update.
 	touch $BASEDIR/$BACKUPKERNELDIR/.freebsd-update
 	if [ $? -ne 0 ]; then
 		echo "Could not create kernel backup directory"
 		exit 1
 	fi
 
 	# Disable pathname expansion to be sure *.symbols is not
 	# expanded.
 	set -f
 
 	# Use find to ignore symbol files, unless disabled by user.
 	if [ $BACKUPKERNELSYMBOLFILES = yes ]; then
 		FINDFILTER=""
 	else
 		FINDFILTER="-a ! -name *.debug -a ! -name *.symbols"
 	fi
 
 	# Backup all the kernel files using hardlinks.
 	(cd ${BASEDIR}/${KERNELDIR} && find . -type f $FINDFILTER -exec \
 	    cp -pl '{}' ${BASEDIR}/${BACKUPKERNELDIR}/'{}' \;)
 
 	# Re-enable patchname expansion.
 	set +f
 }
 
 # Install new files
 install_from_index () {
 	# First pass: Do everything apart from setting file flags.  We
 	# can't set flags yet, because schg inhibits hard linking.
 	sort -k 1,1 -t '|' $1 |
 	    tr '|' ' ' |
 	    while read FPATH TYPE OWNER GROUP PERM FLAGS HASH LINK; do
 		case ${TYPE} in
 		d)
 			# Create a directory
 			install -d -o ${OWNER} -g ${GROUP}		\
 			    -m ${PERM} ${BASEDIR}/${FPATH}
 			;;
 		f)
 			if [ -z "${LINK}" ]; then
 				# Create a file, without setting flags.
 				gunzip < files/${HASH}.gz > ${HASH}
 				install -S -o ${OWNER} -g ${GROUP}	\
 				    -m ${PERM} ${HASH} ${BASEDIR}/${FPATH}
 				rm ${HASH}
 			else
 				# Create a hard link.
 				ln -f ${BASEDIR}/${LINK} ${BASEDIR}/${FPATH}
 			fi
 			;;
 		L)
 			# Create a symlink
 			ln -sfh ${HASH} ${BASEDIR}/${FPATH}
 			;;
 		esac
 	    done
 
 	# Perform a second pass, adding file flags.
 	tr '|' ' ' < $1 |
 	    while read FPATH TYPE OWNER GROUP PERM FLAGS HASH LINK; do
 		if [ ${TYPE} = "f" ] &&
 		    ! [ ${FLAGS} = "0" ]; then
 			chflags ${FLAGS} ${BASEDIR}/${FPATH}
 		fi
 	    done
 }
 
 # Remove files which we want to delete
 install_delete () {
 	# Generate list of new files
 	cut -f 1 -d '|' < $2 |
 	    sort > newfiles
 
 	# Generate subindex of old files we want to nuke
 	sort -k 1,1 -t '|' $1 |
 	    join -t '|' -v 1 - newfiles |
 	    sort -r -k 1,1 -t '|' |
 	    cut -f 1,2 -d '|' |
 	    tr '|' ' ' > killfiles
 
 	# Remove the offending bits
 	while read FPATH TYPE; do
 		case ${TYPE} in
 		d)
 			rmdir ${BASEDIR}/${FPATH}
 			;;
 		f)
 			rm ${BASEDIR}/${FPATH}
 			;;
 		L)
 			rm ${BASEDIR}/${FPATH}
 			;;
 		esac
 	done < killfiles
 
 	# Clean up
 	rm newfiles killfiles
 }
 
 # Install new files, delete old files, and update linker.hints
 install_files () {
 	# If we haven't already dealt with the kernel, deal with it.
 	if ! [ -f $1/kerneldone ]; then
 		grep -E '^/boot/' $1/INDEX-OLD > INDEX-OLD
 		grep -E '^/boot/' $1/INDEX-NEW > INDEX-NEW
 
 		# Backup current kernel before installing a new one
 		backup_kernel || return 1
 
 		# Install new files
 		install_from_index INDEX-NEW || return 1
 
 		# Remove files which need to be deleted
 		install_delete INDEX-OLD INDEX-NEW || return 1
 
 		# Update linker.hints if necessary
 		if [ -s INDEX-OLD -o -s INDEX-NEW ]; then
 			kldxref -R ${BASEDIR}/boot/ 2>/dev/null
 		fi
 
 		# We've finished updating the kernel.
 		touch $1/kerneldone
 
 		# Do we need to ask for a reboot now?
 		if [ -f $1/kernelfirst ] &&
 		    [ -s INDEX-OLD -o -s INDEX-NEW ]; then
 			cat <<-EOF
 
 Kernel updates have been installed.  Please reboot and run
 "$0 install" again to finish installing updates.
 			EOF
 			exit 0
 		fi
 	fi
 
 	# If we haven't already dealt with the world, deal with it.
 	if ! [ -f $1/worlddone ]; then
 		# Create any necessary directories first
 		grep -vE '^/boot/' $1/INDEX-NEW |
 		    grep -E '^[^|]+\|d\|' > INDEX-NEW
 		install_from_index INDEX-NEW || return 1
 
 		# Install new runtime linker
 		grep -vE '^/boot/' $1/INDEX-NEW |
 		    grep -vE '^[^|]+\|d\|' |
 		    grep -E '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' > INDEX-NEW
 		install_from_index INDEX-NEW || return 1
 
 		# Install new shared libraries next
 		grep -vE '^/boot/' $1/INDEX-NEW |
 		    grep -vE '^[^|]+\|d\|' |
 		    grep -vE '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' |
 		    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-NEW
 		install_from_index INDEX-NEW || return 1
 
 		# Deal with everything else
 		grep -vE '^/boot/' $1/INDEX-OLD |
 		    grep -vE '^[^|]+\|d\|' |
 		    grep -vE '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' |
 		    grep -vE '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-OLD
 		grep -vE '^/boot/' $1/INDEX-NEW |
 		    grep -vE '^[^|]+\|d\|' |
 		    grep -vE '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' |
 		    grep -vE '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-NEW
 		install_from_index INDEX-NEW || return 1
 		install_delete INDEX-OLD INDEX-NEW || return 1
 
 		# Rebuild generated pwd files.
 		if [ ${BASEDIR}/etc/master.passwd -nt ${BASEDIR}/etc/spwd.db ] ||
 		    [ ${BASEDIR}/etc/master.passwd -nt ${BASEDIR}/etc/pwd.db ] ||
 		    [ ${BASEDIR}/etc/master.passwd -nt ${BASEDIR}/etc/passwd ]; then
 			pwd_mkdb -d ${BASEDIR}/etc -p ${BASEDIR}/etc/master.passwd
 		fi
 
 		# Rebuild /etc/login.conf.db if necessary.
 		if [ ${BASEDIR}/etc/login.conf -nt ${BASEDIR}/etc/login.conf.db ]; then
 			cap_mkdb ${BASEDIR}/etc/login.conf
 		fi
 
 		# We've finished installing the world and deleting old files
 		# which are not shared libraries.
 		touch $1/worlddone
 
 		# Do we need to ask the user to portupgrade now?
 		grep -vE '^/boot/' $1/INDEX-NEW |
 		    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' |
 		    cut -f 1 -d '|' |
 		    sort > newfiles
 		if grep -vE '^/boot/' $1/INDEX-OLD |
 		    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' |
 		    cut -f 1 -d '|' |
 		    sort |
 		    join -v 1 - newfiles |
 		    grep -q .; then
 			cat <<-EOF
 
 Completing this upgrade requires removing old shared object files.
 Please rebuild all installed 3rd party software (e.g., programs
 installed from the ports tree) and then run "$0 install"
 again to finish installing updates.
 			EOF
 			rm newfiles
 			exit 0
 		fi
 		rm newfiles
 	fi
 
 	# Remove old shared libraries
 	grep -vE '^/boot/' $1/INDEX-NEW |
 	    grep -vE '^[^|]+\|d\|' |
 	    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-NEW
 	grep -vE '^/boot/' $1/INDEX-OLD |
 	    grep -vE '^[^|]+\|d\|' |
 	    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-OLD
 	install_delete INDEX-OLD INDEX-NEW || return 1
 
 	# Remove old directories
 	grep -vE '^/boot/' $1/INDEX-NEW |
 	    grep -E '^[^|]+\|d\|' > INDEX-NEW
 	grep -vE '^/boot/' $1/INDEX-OLD |
 	    grep -E '^[^|]+\|d\|' > INDEX-OLD
 	install_delete INDEX-OLD INDEX-NEW || return 1
 
 	# Remove temporary files
 	rm INDEX-OLD INDEX-NEW
 }
 
 # Rearrange bits to allow the installed updates to be rolled back
 install_setup_rollback () {
 	# Remove the "reboot after installing kernel", "kernel updated", and
 	# "finished installing the world" flags if present -- they are
 	# irrelevant when rolling back updates.
 	if [ -f ${BDHASH}-install/kernelfirst ]; then
 		rm ${BDHASH}-install/kernelfirst
 		rm ${BDHASH}-install/kerneldone
 	fi
 	if [ -f ${BDHASH}-install/worlddone ]; then
 		rm ${BDHASH}-install/worlddone
 	fi
 
 	if [ -L ${BDHASH}-rollback ]; then
 		mv ${BDHASH}-rollback ${BDHASH}-install/rollback
 	fi
 
 	mv ${BDHASH}-install ${BDHASH}-rollback
 }
 
 # Actually install updates
 install_run () {
 	echo -n "Installing updates..."
 
 	# Make sure we have all the files we should have
 	install_verify ${BDHASH}-install/INDEX-OLD	\
 	    ${BDHASH}-install/INDEX-NEW || return 1
 
 	# Remove system immutable flag from files
 	install_unschg ${BDHASH}-install/INDEX-OLD	\
 	    ${BDHASH}-install/INDEX-NEW || return 1
 
 	# Install new files, delete old files, and update linker.hints
 	install_files ${BDHASH}-install || return 1
 
 	# Rearrange bits to allow the installed updates to be rolled back
 	install_setup_rollback
 
 	echo " done."
 }
 
 # Rearrange bits to allow the previous set of updates to be rolled back next.
 rollback_setup_rollback () {
 	if [ -L ${BDHASH}-rollback/rollback ]; then
 		mv ${BDHASH}-rollback/rollback rollback-tmp
 		rm -r ${BDHASH}-rollback/
 		rm ${BDHASH}-rollback
 		mv rollback-tmp ${BDHASH}-rollback
 	else
 		rm -r ${BDHASH}-rollback/
 		rm ${BDHASH}-rollback
 	fi
 }
 
 # Install old files, delete new files, and update linker.hints
 rollback_files () {
 	# Install old shared library files which don't have the same path as
 	# a new shared library file.
 	grep -vE '^/boot/' $1/INDEX-NEW |
 	    grep -E '/lib/.*\.so\.[0-9]+\|' |
 	    cut -f 1 -d '|' |
 	    sort > INDEX-NEW.libs.flist
 	grep -vE '^/boot/' $1/INDEX-OLD |
 	    grep -E '/lib/.*\.so\.[0-9]+\|' |
 	    sort -k 1,1 -t '|' - |
 	    join -t '|' -v 1 - INDEX-NEW.libs.flist > INDEX-OLD
 	install_from_index INDEX-OLD || return 1
 
 	# Deal with files which are neither kernel nor shared library
 	grep -vE '^/boot/' $1/INDEX-OLD |
 	    grep -vE '/lib/.*\.so\.[0-9]+\|' > INDEX-OLD
 	grep -vE '^/boot/' $1/INDEX-NEW |
 	    grep -vE '/lib/.*\.so\.[0-9]+\|' > INDEX-NEW
 	install_from_index INDEX-OLD || return 1
 	install_delete INDEX-NEW INDEX-OLD || return 1
 
 	# Install any old shared library files which we didn't install above.
 	grep -vE '^/boot/' $1/INDEX-OLD |
 	    grep -E '/lib/.*\.so\.[0-9]+\|' |
 	    sort -k 1,1 -t '|' - |
 	    join -t '|' - INDEX-NEW.libs.flist > INDEX-OLD
 	install_from_index INDEX-OLD || return 1
 
 	# Delete unneeded shared library files
 	grep -vE '^/boot/' $1/INDEX-OLD |
 	    grep -E '/lib/.*\.so\.[0-9]+\|' > INDEX-OLD
 	grep -vE '^/boot/' $1/INDEX-NEW |
 	    grep -E '/lib/.*\.so\.[0-9]+\|' > INDEX-NEW
 	install_delete INDEX-NEW INDEX-OLD || return 1
 
 	# Deal with kernel files
 	grep -E '^/boot/' $1/INDEX-OLD > INDEX-OLD
 	grep -E '^/boot/' $1/INDEX-NEW > INDEX-NEW
 	install_from_index INDEX-OLD || return 1
 	install_delete INDEX-NEW INDEX-OLD || return 1
 	if [ -s INDEX-OLD -o -s INDEX-NEW ]; then
 		kldxref -R /boot/ 2>/dev/null
 	fi
 
 	# Remove temporary files
 	rm INDEX-OLD INDEX-NEW INDEX-NEW.libs.flist
 }
 
 # Actually rollback updates
 rollback_run () {
 	echo -n "Uninstalling updates..."
 
 	# If there are updates waiting to be installed, remove them; we
 	# want the user to re-run 'fetch' after rolling back updates.
 	if [ -L ${BDHASH}-install ]; then
 		rm -r ${BDHASH}-install/
 		rm ${BDHASH}-install
 	fi
 
 	# Make sure we have all the files we should have
 	install_verify ${BDHASH}-rollback/INDEX-NEW	\
 	    ${BDHASH}-rollback/INDEX-OLD || return 1
 
 	# Remove system immutable flag from files
 	install_unschg ${BDHASH}-rollback/INDEX-NEW	\
 	    ${BDHASH}-rollback/INDEX-OLD || return 1
 
 	# Install old files, delete new files, and update linker.hints
 	rollback_files ${BDHASH}-rollback || return 1
 
 	# Remove the rollback directory and the symlink pointing to it; and
 	# rearrange bits to allow the previous set of updates to be rolled
 	# back next.
 	rollback_setup_rollback
 
 	echo " done."
 }
 
 # Compare INDEX-ALL and INDEX-PRESENT and print warnings about differences.
 IDS_compare () {
 	# Get all the lines which mismatch in something other than file
 	# flags.  We ignore file flags because sysinstall doesn't seem to
 	# set them when it installs FreeBSD; warning about these adds a
 	# very large amount of noise.
 	cut -f 1-5,7-8 -d '|' $1 > $1.noflags
 	sort -k 1,1 -t '|' $1.noflags > $1.sorted
 	cut -f 1-5,7-8 -d '|' $2 |
 	    comm -13 $1.noflags - |
 	    fgrep -v '|-|||||' |
 	    sort -k 1,1 -t '|' |
 	    join -t '|' $1.sorted - > INDEX-NOTMATCHING
 
 	# Ignore files which match IDSIGNOREPATHS.
 	for X in ${IDSIGNOREPATHS}; do
 		grep -E "^${X}" INDEX-NOTMATCHING
 	done |
 	    sort -u |
 	    comm -13 - INDEX-NOTMATCHING > INDEX-NOTMATCHING.tmp
 	mv INDEX-NOTMATCHING.tmp INDEX-NOTMATCHING
 
 	# Go through the lines and print warnings.
 	local IFS='|'
 	while read FPATH TYPE OWNER GROUP PERM HASH LINK P_TYPE P_OWNER P_GROUP P_PERM P_HASH P_LINK; do
 		# Warn about different object types.
 		if ! [ "${TYPE}" = "${P_TYPE}" ]; then
 			echo -n "${FPATH} is a "
 			case "${P_TYPE}" in
 			f)	echo -n "regular file, "
 				;;
 			d)	echo -n "directory, "
 				;;
 			L)	echo -n "symlink, "
 				;;
 			esac
 			echo -n "but should be a "
 			case "${TYPE}" in
 			f)	echo -n "regular file."
 				;;
 			d)	echo -n "directory."
 				;;
 			L)	echo -n "symlink."
 				;;
 			esac
 			echo
 
 			# Skip other tests, since they don't make sense if
 			# we're comparing different object types.
 			continue
 		fi
 
 		# Warn about different owners.
 		if ! [ "${OWNER}" = "${P_OWNER}" ]; then
 			echo -n "${FPATH} is owned by user id ${P_OWNER}, "
 			echo "but should be owned by user id ${OWNER}."
 		fi
 
 		# Warn about different groups.
 		if ! [ "${GROUP}" = "${P_GROUP}" ]; then
 			echo -n "${FPATH} is owned by group id ${P_GROUP}, "
 			echo "but should be owned by group id ${GROUP}."
 		fi
 
 		# Warn about different permissions.  We do not warn about
 		# different permissions on symlinks, since some archivers
 		# don't extract symlink permissions correctly and they are
 		# ignored anyway.
 		if ! [ "${PERM}" = "${P_PERM}" ] &&
 		    ! [ "${TYPE}" = "L" ]; then
 			echo -n "${FPATH} has ${P_PERM} permissions, "
 			echo "but should have ${PERM} permissions."
 		fi
 
 		# Warn about different file hashes / symlink destinations.
 		if ! [ "${HASH}" = "${P_HASH}" ]; then
 			if [ "${TYPE}" = "L" ]; then
 				echo -n "${FPATH} is a symlink to ${P_HASH}, "
 				echo "but should be a symlink to ${HASH}."
 			fi
 			if [ "${TYPE}" = "f" ]; then
 				echo -n "${FPATH} has SHA256 hash ${P_HASH}, "
 				echo "but should have SHA256 hash ${HASH}."
 			fi
 		fi
 
 		# We don't warn about different hard links, since some
 		# some archivers break hard links, and as long as the
 		# underlying data is correct they really don't matter.
 	done < INDEX-NOTMATCHING
 
 	# Clean up
 	rm $1 $1.noflags $1.sorted $2 INDEX-NOTMATCHING
 }
 
 # Do the work involved in comparing the system to a "known good" index
 IDS_run () {
 	workdir_init || return 1
 
 	# Prepare the mirror list.
 	fetch_pick_server_init && fetch_pick_server
 
 	# Try to fetch the public key until we run out of servers.
 	while ! fetch_key; do
 		fetch_pick_server || return 1
 	done
  
 	# Try to fetch the metadata index signature ("tag") until we run
 	# out of available servers; and sanity check the downloaded tag.
 	while ! fetch_tag; do
 		fetch_pick_server || return 1
 	done
 	fetch_tagsanity || return 1
 
 	# Fetch INDEX-OLD and INDEX-ALL.
 	fetch_metadata INDEX-OLD INDEX-ALL || return 1
 
 	# Generate filtered INDEX-OLD and INDEX-ALL files containing only
 	# the components we want and without anything marked as "Ignore".
 	fetch_filter_metadata INDEX-OLD || return 1
 	fetch_filter_metadata INDEX-ALL || return 1
 
 	# Merge the INDEX-OLD and INDEX-ALL files into INDEX-ALL.
 	sort INDEX-OLD INDEX-ALL > INDEX-ALL.tmp
 	mv INDEX-ALL.tmp INDEX-ALL
 	rm INDEX-OLD
 
 	# Translate /boot/${KERNCONF} to ${KERNELDIR}
 	fetch_filter_kernel_names INDEX-ALL ${KERNCONF}
 
 	# Inspect the system and generate an INDEX-PRESENT file.
 	fetch_inspect_system INDEX-ALL INDEX-PRESENT /dev/null || return 1
 
 	# Compare INDEX-ALL and INDEX-PRESENT and print warnings about any
 	# differences.
 	IDS_compare INDEX-ALL INDEX-PRESENT
 }
 
 #### Main functions -- call parameter-handling and core functions
 
 # Using the command line, configuration file, and defaults,
 # set all the parameters which are needed later.
 get_params () {
 	init_params
 	parse_cmdline $@
 	parse_conffile
 	default_params
 }
 
 # Fetch command.  Make sure that we're being called
 # interactively, then run fetch_check_params and fetch_run
 cmd_fetch () {
 	if [ ! -t 0 -a $NOTTYOK -eq 0 ]; then
 		echo -n "`basename $0` fetch should not "
 		echo "be run non-interactively."
 		echo "Run `basename $0` cron instead."
 		exit 1
 	fi
 	fetch_check_params
 	fetch_run || exit 1
 	ISFETCHED=1
 }
 
 # Cron command.  Make sure the parameters are sensible; wait
 # rand(3600) seconds; then fetch updates.  While fetching updates,
 # send output to a temporary file; only print that file if the
 # fetching failed.
 cmd_cron () {
 	fetch_check_params
 	sleep `jot -r 1 0 3600`
 
 	TMPFILE=`mktemp /tmp/freebsd-update.XXXXXX` || exit 1
 	if ! fetch_run >> ${TMPFILE} ||
 	    ! grep -q "No updates needed" ${TMPFILE} ||
 	    [ ${VERBOSELEVEL} = "debug" ]; then
 		mail -s "`hostname` security updates" ${MAILTO} < ${TMPFILE}
 	fi
 
 	rm ${TMPFILE}
 }
 
 # Fetch files for upgrading to a new release.
 cmd_upgrade () {
 	upgrade_check_params
 	upgrade_run || exit 1
 }
 
 # Install downloaded updates.
 cmd_install () {
 	install_check_params
 	install_run || exit 1
 }
 
 # Rollback most recently installed updates.
 cmd_rollback () {
 	rollback_check_params
 	rollback_run || exit 1
 }
 
 # Compare system against a "known good" index.
 cmd_IDS () {
 	IDS_check_params
 	IDS_run || exit 1
 }
 
 #### Entry point
 
 # Make sure we find utilities from the base system
 export PATH=/sbin:/bin:/usr/sbin:/usr/bin:${PATH}
 
 # Set a pager if the user doesn't
 if [ -z "$PAGER" ]; then
 	PAGER=/usr/bin/less
 fi
 
 # Set LC_ALL in order to avoid problems with character ranges like [A-Z].
 export LC_ALL=C
 
 get_params $@
 for COMMAND in ${COMMANDS}; do
 	cmd_${COMMAND}
 done