# -*- sh -*-
# vi:syntax=sh
# This is a shell function library sourced by some Open vSwitch scripts.
# It is not intended to be invoked on its own.

# Copyright (C) 2009, 2010, 2011, 2012 Nicira, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

## ----------------- ##
## configure options ##
## ----------------- ##

# All of these should be substituted by the Makefile at build time.
logdir=${OVS_LOGDIR-'@LOGDIR@'}                 # /var/log/openvswitch
rundir=${OVS_RUNDIR-'@RUNDIR@'}                 # /var/run/openvswitch
sysconfdir=${OVS_SYSCONFDIR-'@sysconfdir@'}     # /etc
etcdir=$sysconfdir/openvswitch                  # /etc/openvswitch
datadir=${OVS_PKGDATADIR-'@pkgdatadir@'}        # /usr/share/openvswitch
bindir=${OVS_BINDIR-'@bindir@'}                 # /usr/bin
sbindir=${OVS_SBINDIR-'@sbindir@'}              # /usr/sbin

# /etc/openvswitch or /var/lib/openvswitch
if test X"$OVS_DBDIR" != X; then
    dbdir=$OVS_DBDIR
elif test X"$OVS_SYSCONFDIR" != X; then
    dbdir=$OVS_SYSCONFDIR/openvswitch
else
    dbdir='@DBDIR@'
fi

ovs_ctl_log () {
    echo "$@" >> "${logdir}/ovs-ctl.log"
}

ovs_ctl () {
    case "$@" in
        *"=strace"*)
            # In case of running the daemon with strace, piping the o/p causes
            # the script to block (strace probably does not close the inherited
            # pipe). So, do not log the o/p to ovs-ctl.log.
            "${datadir}/scripts/ovs-ctl" "$@"
        ;;
        "status")
            # In case of the command 'status', we should return the exit status
            # of ovs-ctl. It is also useful to document the o/p in ovs-ctl.log.
            display=`"${datadir}/scripts/ovs-ctl" "$@" 2>&1`
            rc=$?
            if test -w "${logdir}/ovs-ctl.log"; then
                 echo "${display}" | tee -a "${logdir}/ovs-ctl.log"
            else
                 echo "${display}"
            fi
            return ${rc}
        ;;
        *)
            echo "`date -u`:$@" >> "${logdir}/ovs-ctl.log"
            "${datadir}/scripts/ovs-ctl" "$@" 2>&1 | tee -a "${logdir}/ovs-ctl.log"
        ;;
    esac
}

VERSION='@VERSION@'

DAEMON_CWD=/

LC_ALL=C; export LC_ALL

## ------------- ##
## LSB functions ##
## ------------- ##

# Use the system's own implementations if it has any.
if test -e /etc/init.d/functions; then
    . /etc/init.d/functions
elif test -e /etc/rc.d/init.d/functions; then
    . /etc/rc.d/init.d/functions
elif test -e /lib/lsb/init-functions; then
    . /lib/lsb/init-functions
fi

# Implement missing functions (e.g. OpenSUSE lacks 'action').
if type log_success_msg >/dev/null 2>&1; then :; else
    log_success_msg () {
        printf '%s.\n' "$*"
    }
fi
if type log_failure_msg >/dev/null 2>&1; then :; else
    log_failure_msg () {
        printf '%s ... failed!\n' "$*"
    }
fi
if type log_warning_msg >/dev/null 2>&1; then :; else
    log_warning_msg () {
        printf '%s ... (warning).\n' "$*"
    }
fi
if type action >/dev/null 2>&1; then :; else
    action () {
       STRING=$1
       shift
       "$@"
       rc=$?
       if test $rc = 0; then
            log_success_msg "$STRING"
       else
            log_failure_msg "$STRING"
       fi
       return $rc
    }
fi

## ------- ##
## Daemons ##
## ------- ##

pid_exists () {
    # This is better than "kill -0" because it doesn't require permission to
    # send a signal (so daemon_status in particular works as non-root).
    test -n "$1" && test -d /proc/"$1"
}

pid_comm_check () {
    [ "$1" = "`cat /proc/$2/comm`" ]
}

# version_geq version_a version_b
#
# Compare (dot separated) version numbers.  Returns true (exit code 0) if
# version_a is greater or equal than version_b, otherwise false (exit code 1).
version_geq() {
    echo $1 $2 | awk '{
        n1 = split($1, a, ".");
        n2 = split($2, b, ".");
        n = (n1 > n2) ? n1 : n2;
        for (i = 1; i <= n; i++) {
            if (a[i]+0 < b[i]+0) exit 1
            if (a[i]+0 > b[i]+0) exit 0
        }
    }'
}

install_dir () {
    DIR="$1"
    INSTALL_MODE="${2:-755}"
    INSTALL_USER="root"
    INSTALL_GROUP="root"
    [ "$OVS_USER" != "" ] && INSTALL_USER="${OVS_USER%:*}"
    [ "${OVS_USER##*:}" != "" ] && INSTALL_GROUP="${OVS_USER##*:}"

    if test ! -d "$DIR"; then
        install -d -m "$INSTALL_MODE" -o "$INSTALL_USER" -g "$INSTALL_GROUP" "$DIR"
        restorecon "$DIR" >/dev/null 2>&1
    fi
}

start_daemon () {
    priority=$1 && shift
    wrapper=$1 && shift
    umask=$1 && shift
    daemon=$1
    strace=""

    # drop core files in a sensible place
    install_dir "$DAEMON_CWD"
    set "$@" --no-chdir
    cd "$DAEMON_CWD"

    # log file
    install_dir "$logdir" "750"
    set "$@" --log-file="$logdir/$daemon.log"

    # pidfile and monitoring
    install_dir "$rundir"
    set "$@" --pidfile="$rundir/$daemon.pid"
    set "$@" --detach
    test X"$MONITOR" = Xno || set "$@" --monitor

    # wrapper
    case $wrapper in
        valgrind)
            if (valgrind --version) > /dev/null 2>&1; then
                set valgrind -q --leak-check=full --time-stamp=yes \
                    --log-file="$logdir/$daemon.valgrind.log.%p" "$@"
            else
                log_failure_msg "valgrind not installed, running $daemon without it"
            fi
            ;;
        strace)
            if (strace -V) > /dev/null 2>&1; then
                strace="strace -tt -T -s 256 -ff"
                if (strace -DV) > /dev/null 2>&1; then
                    # Has the -D option.
                    set $strace -D -o "$logdir/$daemon.strace.log" "$@"
                    strace=""
                fi
            else
                log_failure_msg "strace not installed, running $daemon without it"
            fi
            ;;
        glibc)
            set env MALLOC_CHECK_=2 MALLOC_PERTURB_=165 "$@"
            ;;
        '')
            ;;
        *)
            log_failure_msg "unknown wrapper $wrapper, running $daemon without it"
            ;;
    esac

    # priority
    if test X"$priority" != X; then
        set nice -n "$priority" "$@"
    fi

    # Set requested umask if any and turn previous value back.
    if [ -n "$umask" ]; then
        previuos_umask_value=$(umask)
        umask "$umask"
    fi

    action "Starting $daemon" "$@" || return 1

    # If umask was set, turn umask value to previous value.
    if [ -n "$umask" ]; then
        umask "$previuos_umask_value"
    fi

    if test X"$strace" != X; then
        # Strace doesn't have the -D option so we attach after the fact.
        setsid $strace -o "$logdir/$daemon.strace.log" \
            -p `cat $rundir/$daemon.pid` > /dev/null 2>&1 &
    fi
}

stop_daemon () {
    if test -e "$rundir/$1.pid"; then
        if pid=`cat "$rundir/$1.pid"`; then
            if pid_exists "$pid" >/dev/null 2>&1; then :; else
                rm -f $rundir/$1.$pid.ctl $rundir/$1.$pid
                return 0
            fi

            graceful="EXIT .1 .25 .65 1"
            actions="TERM .1 .25 .65 1 1 1 1 \
                     KILL 1 1 1 2 10 15 30 \
                     FAIL"
            version=`ovs-appctl -T 1 -t $rundir/$1.$pid.ctl version \
                     | awk 'NR==1{print $NF}'`

            # Use `ovs-appctl exit` only if the running daemon version
            # is >= 2.5.90.  This script might be used during upgrade to
            # stop older versions of daemons which do not behave correctly
            # with `ovs-appctl exit` (e.g. ovs-vswitchd <= 2.5.0 deletes
            # internal ports).
            if version_geq "$version" "2.5.90"; then
                actions="$graceful $actions"
            fi
            actiontype=""
            for action in $actions; do
                if pid_exists "$pid" >/dev/null 2>&1; then :; else
                    # pid does not exist.
                    if [ -n "$actiontype" ]; then
                        return 0
                    fi
                    # But, does the file exist? We may have had a daemon
                    # segfault with `ovs-appctl exit`. Check one more time
                    # before deciding that the daemon is dead.
                    [ -e "$rundir/$1.pid" ] && sleep 2 && pid=`cat "$rundir/$1.pid"` 2>/dev/null
                    if pid_exists "$pid" >/dev/null 2>&1; then :; else
                        return 0
                    fi
                fi
                case $action in
                    EXIT)
                        action "Exiting $1 ($pid)" \
                            ${bindir}/ovs-appctl -T 1 -t $rundir/$1.$pid.ctl exit
                        # The above command could have resulted in delayed
                        # daemon segfault. And if a monitor is running, it
                        # would restart the daemon giving it a new pid.
                        ;;
                    TERM)
                        action "Killing $1 ($pid)" kill $pid
                        actiontype="force"
                        ;;
                    KILL)
                        action "Killing $1 ($pid) with SIGKILL" kill -9 $pid
                        actiontype="force"
                        ;;
                    FAIL)
                        log_failure_msg "Killing $1 ($pid) failed"
                        return 1
                        ;;
                    *)
                        sleep $action
                        ;;
                esac
            done
        fi
    fi
    log_success_msg "$1 is not running"
}

daemon_status () {
    pidfile=$rundir/$1.pid
    if test -e "$pidfile"; then
        if pid=`cat "$pidfile"`; then
            if pid_exists "$pid"; then
                echo "$1 is running with pid $pid"
                return 0
            else
                echo "Pidfile for $1 ($pidfile) is stale"
            fi
        else
            echo "Pidfile for $1 ($pidfile) exists but cannot be read"
        fi
    else
        echo "$1 is not running"
    fi
    return 1
}

daemon_is_running () {
    pidfile=$rundir/$1.pid
    test -e "$pidfile" && pid=`cat "$pidfile"` && pid_exists "$pid" && pid_comm_check $1 $pid
} >/dev/null 2>&1

# Prints commands needed to move the ip address from interface $1 to interface
# $2
move_ip_address () {
    if [ -z "$1" ] || [ -z "$2" ]; then
        return
    fi
    dev="$1"
    dst="$2"

    # IP addresses (including IPv6).
    echo "ip addr flush dev $dev 2>/dev/null" # Suppresses "Nothing to flush".
    ip addr show dev $dev | while read addr; do
        set -- $addr

        # Check and trim family.
        family=$1
        shift
        case $family in
            inet | inet6) ;;
            *) continue ;;
        esac

        # Trim device off the end--"ip" insists on having "dev" precede it.
        addrcmd=
        while test $# != 0; do
            case $1 in
                dynamic)
                    # XXX: According to 'man ip-address', "dynamic" is only
                    # used for ipv6 addresses.  But, atleast on RHEL 7.4
                    # (iproute-3.10.0-87), it is being used for ipv4
                    # addresses assigned with dhcp.
                    if [ "$family" = "inet" ]; then
                        shift
                        continue
                    fi
                    # Omit kernel-maintained route.
                    continue 2
                    ;;
                scope)
                    if test "$2" = link -a "$family" != inet6; then
                        # Omit route derived from IP address, e.g.
                        # 172.16.0.0/16 derived from 172.16.12.34,
                        # but preserve IPv6 link-local address.
                        continue 2
                    fi
                    ;;
                "$dev"|"$dev:"*)
                    # Address label string
                    label=`echo $1 | sed "s/$dev/$dst/"`
                    addrcmd="$addrcmd label $label"
                    shift
                    continue
                    ;;
            esac
            addrcmd="$addrcmd $1"
            shift
        done
        if test "$1" != "$dev"; then
            addrcmd="$addrcmd $1"
        fi

        echo ip -f $family addr add $addrcmd dev $dst
    done
}

# Prints commands needed to move the ip route of interface $1 to interface $2
move_ip_routes () {
    if [ -z "$1" ] || [ -z "$2" ]; then
        return
    fi
    dev="$1"
    dst="$2"
    echo "ip route flush dev $dev proto boot 2>/dev/null" # Suppresses "Nothing to flush".
    ip route show dev $dev | while read route; do
        # "proto kernel" routes are installed by the kernel automatically.
        case $route in
            *" proto kernel "*) continue ;;
        esac

        echo "ip route add $route dev $dst"
    done
}

run_as_ovsuser() {
    if [ "$OVS_USER" != "" ]; then
        local uid=$(id -u "${OVS_USER%:*}")
        local gid=$(id -g "${OVS_USER%:*}")
        local groups=$(id -G "${OVS_USER%:*}" | tr ' ' ',')
        setpriv --reuid "$uid" --regid "$gid" --groups "$groups" "$@"
    else
        "$@"
    fi
}

ovsdb_tool () {
    run_as_ovsuser ovsdb-tool -vconsole:off "$@"
}

create_db () {
    DB_FILE="$1"
    DB_SCHEMA="$2"
    action "Creating empty database $DB_FILE" ovsdb_tool create "$DB_FILE" "$DB_SCHEMA"
}

backup_db () {
    # Back up the old version.
    version=`ovsdb_tool db-version "$DB_FILE"`
    cksum=`ovsdb_tool db-cksum "$DB_FILE" | awk '{print $1}'`
    backup=$DB_FILE.backup$version-$cksum
    action "Backing up database to $backup" cp "$DB_FILE" "$backup" || return 1
}

upgrade_db () {
    DB_FILE="$1"
    DB_SCHEMA="$2"

    schemaver=`ovsdb_tool schema-version "$DB_SCHEMA"`
    if test ! -e "$DB_FILE"; then
        log_warning_msg "$DB_FILE does not exist"
        install_dir `dirname $DB_FILE`
        create_db "$DB_FILE" "$DB_SCHEMA"
    elif test X"`ovsdb_tool needs-conversion "$DB_FILE" "$DB_SCHEMA"`" = Xyes; then
        backup_db || return 1

        # Compact database.  This is important if the old schema did not enable
        # garbage collection (i.e. if it did not have any tables with "isRoot":
        # true) but the new schema does.  In that situation the old database
        # may contain a transaction that creates a record followed by a
        # transaction that creates the first use of the record.  Replaying that
        # series of transactions against the new database schema (as "convert"
        # does) would cause the record to be dropped by the first transaction,
        # then the second transaction would cause a referential integrity
        # failure (for a strong reference).
        #
        # Errors might occur on an Open vSwitch downgrade if ovsdb-tool doesn't
        # understand some feature of the schema used in the OVSDB version that
        # we're downgrading from, so we don't give up on error.
        action "Compacting database" ovsdb_tool compact "$DB_FILE"

        # Upgrade or downgrade schema.
        if action "Converting database schema" ovsdb_tool convert "$DB_FILE" "$DB_SCHEMA"; then
            :
        else
            log_warning_msg "Schema conversion failed, using empty database instead"
            rm -f "$DB_FILE"
            create_db "$DB_FILE" "$DB_SCHEMA"
        fi
    fi
}

upgrade_cluster () {
    local DB_SCHEMA=$1 DB_SERVER=$2
    local schema_name=$(ovsdb-tool schema-name $1) || return 1

    action "Waiting for $schema_name to come up" ovsdb-client -t 30 wait "$DB_SERVER" "$schema_name" connected || return $?
    local db_version=$(ovsdb-client -t 10 get-schema-version "$DB_SERVER" "$schema_name") || return $?
    local target_version=$(ovsdb-tool schema-version "$DB_SCHEMA") || return $?

    if ovsdb-tool compare-versions "$db_version" == "$target_version"; then
        :
    elif ovsdb-tool compare-versions "$db_version" ">" "$target_version"; then
        log_warning_msg "Database $schema_name has newer schema version ($db_version) than our local schema ($target_version), possibly an upgrade is partially complete?"
    else
        action "Upgrading database $schema_name from schema version $db_version to $target_version" ovsdb-client -t 30 convert "$DB_SERVER" "$DB_SCHEMA"
    fi
}

create_cluster () {
    DB_FILE="$1"
    DB_SCHEMA="$2"
    LOCAL_ADDR="$3"
    ELECTION_TIMER_MS="$4"

    election_timer_arg=
    if [ -n "$ELECTION_TIMER_MS" ]; then
      election_timer_arg="--election-timer=$ELECTION_TIMER_MS"
    fi

    if test ! -e "$DB_FILE"; then
        action "Creating cluster database $DB_FILE" ovsdb_tool $election_timer_arg create-cluster "$DB_FILE" "$DB_SCHEMA" "$LOCAL_ADDR"
    elif ovsdb_tool db-is-standalone "$DB_FILE"; then
        # Convert standalone database to clustered.
        backup_db || return 1
        rm -f "$DB_FILE"
        action "Creating cluster database $DB_FILE from existing one" \
               ovsdb_tool $election_timer_arg create-cluster "$DB_FILE" "$backup" "$LOCAL_ADDR"
    fi
}

join_cluster() {
    DB_FILE="$1"
    SCHEMA_NAME="$2"
    LOCAL_ADDR="$3"
    REMOTE_ADDR="$4"

    if test -e "$DB_FILE" && ovsdb_tool db-is-standalone "$DB_FILE"; then
        backup_db || return 1
        rm $DB_FILE
    fi
    if test ! -e "$DB_FILE"; then
        action "Joining $DB_FILE to cluster" \
               ovsdb_tool join-cluster "$DB_FILE" "$SCHEMA_NAME" "$LOCAL_ADDR" "$REMOTE_ADDR"
    fi
}

ovs_vsctl () {
    ovs-vsctl --no-wait "$@"
}

## ----------------- ##
## force-reload-kmod ##
## ----------------- ##

ovs_kmod_ctl () {
    "$dir0/ovs-kmod-ctl" "$@"
}

internal_interfaces () {
    # Outputs a list of internal interfaces:
    #
    #   - There is an internal interface for every bridge, whether it
    #     has an Interface record or not and whether the Interface
    #     record's 'type' is properly set or not.
    #
    #   - There is an internal interface for each Interface record whose
    #     'type' is 'internal'.
    #
    # But ignore interfaces that don't really exist.
    for d in `(ovs_vsctl --bare \
                -- --columns=name find Interface type=internal \
                    -- list-br) | sort -u`
    do
        if test -e "/sys/class/net/$d"; then
                printf "%s " "$d"
            fi
    done
}

ovs_save () {
    bridges=`ovs_vsctl -- --real list-br`
    if [ -n "${bridges}" ] && \
        "$datadir/scripts/ovs-save" "$1" ${bridges} > "$2"; then
        chmod +x "$2"
        return 0
    fi
    [ -z "${bridges}" ] && return 0
}

save_flows_if_required () {
    if test X"$DELETE_BRIDGES" != Xyes; then
        action "Saving flows" ovs_save save-flows "${script_flows}"
    fi
}

save_interfaces () {
    "$datadir/scripts/ovs-save" save-interfaces ${ifaces} \
        > "${script_interfaces}"
}

flow_restore_wait () {
    if test X"${OVS_VSWITCHD:-yes}" = Xyes; then
        ovs_vsctl set open_vswitch . other_config:flow-restore-wait="true"
    fi
}

flow_restore_complete () {
    if test X"${OVS_VSWITCHD:-yes}" = Xyes; then
        ovs_vsctl --if-exists remove open_vswitch . other_config \
                  flow-restore-wait="true"
    fi
}

restore_flows () {
    [ -x "${script_flows}" ] && \
        action "Restoring saved flows" "${script_flows}"
}

restore_interfaces () {
    [ ! -x "${script_interfaces}" ] && return 0
    action "Restoring interface configuration" "${script_interfaces}"
    rc=$?
    if test $rc = 0; then
        level=debug
    else
        level=err
    fi
    log="logger -p daemon.$level -t ovs-save"
    $log "interface restore script exited with status $rc:"
    $log -f "$script_interfaces"
}

init_restore_scripts () {
    script_interfaces=`mktemp`
    script_flows=`mktemp`
    trap 'rm -f "${script_interfaces}" "${script_flows}"' 0
}

force_reload_kmod () {

    if test X"${OVS_VSWITCHD:-yes}" != Xyes; then
        log_failure_msg "Reloading of kmod without ovs-vswitchd is an error"
        exit 1
    fi

    ifaces=`internal_interfaces`
    action "Detected internal interfaces: $ifaces" true

    init_restore_scripts
    save_flows_if_required

    # Restart the database first, since a large database may take a
    # while to load, and we want to minimize forwarding disruption.
    stop_ovsdb
    start_ovsdb || return 1

    stop_forwarding

    if action "Saving interface configuration" save_interfaces; then
        :
    else
        log_warning_msg "Failed to save configuration, not replacing kernel module"
        start_forwarding
        add_managers
        exit 1
    fi
    chmod +x "$script_interfaces"

    for dp in `ovs-dpctl dump-dps`; do
        action "Removing datapath: $dp" ovs-dpctl del-dp "$dp"
    done

    if test -e /sys/module/ip_gre; then
        action "Forcing removal of ip_gre module" rmmod ip_gre
    fi

    if test -e /sys/module/gre; then
        action "Forcing removal of gre module" rmmod gre
    fi

    ovs_kmod_ctl remove

    # Start vswitchd by asking it to wait till flow restore is finished.
    flow_restore_wait
    start_forwarding || return 1

    # Restore saved flows and inform vswitchd that we are done.
    restore_flows
    flow_restore_complete
    add_managers

    restore_interfaces

    action "Finding processes on dead interfaces" timeout 5 \
        "$datadir/scripts/ovs-check-dead-ifs" || true
}

## ------- ##
## restart ##
## ------- ##

restart () {
    if daemon_is_running ovsdb-server && daemon_is_running ovs-vswitchd; then
        init_restore_scripts
        if test X"${OVS_VSWITCHD:-yes}" = Xyes; then
            save_flows_if_required
        fi
    fi

    # Restart the database first, since a large database may take a
    # while to load, and we want to minimize forwarding disruption.
    stop_ovsdb
    start_ovsdb || return 1

    stop_forwarding

    # Start vswitchd by asking it to wait till flow restore is finished.
    flow_restore_wait
    start_forwarding || return 1

    # Restore saved flows and inform vswitchd that we are done.
    restore_flows
    flow_restore_complete
    add_managers
}
