Updated on 2024-07-19 GMT+08:00

Example of Issuing a Certificate

Generate the generate_keystore.sh script based on the sample code and save the script to the bin directory on the Flink client.

#!/bin/bash

KEYTOOL=${JAVA_HOME}/bin/keytool
KEYSTOREPATH="$FLINK_HOME/conf/"
CA_ALIAS="ca"
CA_KEYSTORE_NAME="ca.keystore"
CA_DNAME="CN=Flink_CA"
CA_KEYALG="RSA"
CLIENT_CONF_YAML="$FLINK_HOME/conf/flink-conf.yaml"
KEYTABPRINCEPAL=""

function getConf()
{
    if [ $# -ne 2 ]; then
        echo "invalid parameters for getConf"
        exit 1
    fi

    confName="$1"
    if [ -z "$confName" ]; then
        echo "conf name is empty."
        exit 2
    fi

    configFile=$FLINK_HOME/conf/client.properties
    if [ ! -f $configFile ]; then
        echo $configFile" is not exist."
        exit 3
    fi

    defaultValue="$2"
    cnt=$(grep $1 $configFile | wc -l)
    if [ $cnt -gt 1 ]; then
        echo $confName" has multi values in "$configFile
        exit 4
    elif [ $cnt -lt 1 ]; then
        echo $defaultValue
    else
        line=$(grep $1 $configFile)
        confValue=$(echo "${line#*=}")
        echo "$confValue"
    fi
}

function createSelfSignedCA()
{
    #varible from user input
    keystorePath=$1
    storepassValue=$2
    keypassValue=$3

    #generate ca keystore
    rm -rf $keystorePath/$CA_KEYSTORE_NAME
    $KEYTOOL -genkeypair -alias $CA_ALIAS -keystore $keystorePath/$CA_KEYSTORE_NAME -dname $CA_DNAME -storepass $storepassValue -keypass $keypassValue -validity 3650 -keyalg $CA_KEYALG -keysize 3072 -ext bc=ca:true
    if [ $? -ne 0 ]; then
        echo "generate ca.keystore failed."
        exit 1
    fi

    #generate ca.cer
    rm -rf "$keystorePath/ca.cer"
    $KEYTOOL -keystore "$keystorePath/$CA_KEYSTORE_NAME" -storepass "$storepassValue" -alias $CA_ALIAS -validity 3650 -exportcert > "$keystorePath/ca.cer"
    if [ $? -ne 0 ]; then
        echo "generate ca.cer failed."
        exit 1
    fi

    #generate ca.truststore
    rm -rf "$keystorePath/flink.truststore"
    $KEYTOOL -importcert -keystore "$keystorePath/flink.truststore" -alias $CA_ALIAS -storepass "$storepassValue" -noprompt -file "$keystorePath/ca.cer"
    if [ $? -ne 0 ]; then
        echo "generate ca.truststore failed."
        exit 1
    fi
}

function generateKeystore()
{
    #get path/pass from input
    keystorePath=$1
    storepassValue=$2
    keypassValue=$3

    #get value from conf
    aliasValue=$(getConf "flink.keystore.rsa.alias" "flink")
    validityValue=$(getConf "flink.keystore.rsa.validity" "3650")
    keyalgValue=$(getConf "flink.keystore.rsa.keyalg" "RSA")
    dnameValue=$(getConf "flink.keystore.rsa.dname" "CN=flink.com")
    SANValue=$(getConf "flink.keystore.rsa.ext" "ip:127.0.0.1")
    SANValue=$(echo "$SANValue" | xargs)
    SANValue="ip:$(echo "$SANValue"| sed 's/,/,ip:/g')"

    #generate keystore
    rm -rf $keystorePath/flink.keystore
    $KEYTOOL -genkeypair -alias $aliasValue -keystore $keystorePath/flink.keystore -dname $dnameValue -ext SAN=$SANValue -storepass $storepassValue -keypass $keypassValue -keyalg $keyalgValue -keysize 3072 -validity 3650
    if [ $? -ne 0 ]; then
        echo "generate flink.keystore failed."
        exit 1
    fi

    #generate cer
    rm -rf $keystorePath/flink.csr
    $KEYTOOL -certreq -keystore $keystorePath/flink.keystore -storepass $storepassValue -alias $aliasValue -file $keystorePath/flink.csr
    if [ $? -ne 0 ]; then
        echo "generate flink.csr failed."
        exit 1
    fi

    #generate flink.cer
    rm -rf $keystorePath/flink.cer
    $KEYTOOL -gencert -keystore $keystorePath/ca.keystore -storepass $storepassValue -alias $CA_ALIAS -ext SAN=$SANValue -infile $keystorePath/flink.csr -outfile $keystorePath/flink.cer -validity 3650
    if [ $? -ne 0 ]; then
        echo "generate flink.cer failed."
        exit 1
    fi

    #import cer into keystore
    $KEYTOOL -importcert -keystore $keystorePath/flink.keystore -storepass $storepassValue -file $keystorePath/ca.cer -alias $CA_ALIAS -noprompt
    if [ $? -ne 0 ]; then
        echo "importcert ca."
        exit 1
    fi

    $KEYTOOL -importcert -keystore $keystorePath/flink.keystore -storepass $storepassValue -file $keystorePath/flink.cer -alias $aliasValue -noprompt;
    if [ $? -ne 0 ]; then
        echo "generate flink.truststore failed."
        exit 1
    fi
}

function configureFlinkConf()
{
    # set config
    if [ -f "$CLIENT_CONF_YAML" ]; then
        SSL_ENCRYPT_ENABLED=$(grep "security.ssl.encrypt.enabled" "$CLIENT_CONF_YAML" | awk '{print $2}')
        if [ "$SSL_ENCRYPT_ENABLED" = "false" ];then

            sed -i s/"security.ssl.key-password:".*/"security.ssl.key-password:"\ "${keyPass}"/g "$CLIENT_CONF_YAML"
            if [ $? -ne 0 ]; then
                echo "set security.ssl.key-password failed."
                return 1
            fi

            sed -i s/"security.ssl.keystore-password:".*/"security.ssl.keystore-password:"\ "${storePass}"/g "$CLIENT_CONF_YAML"
            if [ $? -ne 0 ]; then
                echo "set security.ssl.keystore-password failed."
                return 1
            fi

            sed -i s/"security.ssl.truststore-password:".*/"security.ssl.truststore-password:"\ "${storePass}"/g "$CLIENT_CONF_YAML"
            if [ $? -ne 0 ]; then
                echo "set security.ssl.keystore-password failed."
                return 1
            fi

            echo "security.ssl.encrypt.enabled is false, set security.ssl.key-password security.ssl.keystore-password security.ssl.truststore-password success."
        else
            echo "security.ssl.encrypt.enabled is true, please enter security.ssl.key-password security.ssl.keystore-password security.ssl.truststore-password encrypted value in flink-conf.yaml."
        fi

        keystoreFilePath="${keystorePath}"/flink.keystore
        sed -i 's#'"security.ssl.keystore:".*'#'"security.ssl.keystore:"\ "$keystoreFilePath"'#g' "$CLIENT_CONF_YAML"
        if [ $? -ne 0 ]; then
            echo "set security.ssl.keystore failed."
            return 1
        fi


        truststoreFilePath="${keystorePath}/flink.truststore"
        sed -i 's#'"security.ssl.truststore:".*'#'"security.ssl.truststore:"\ "$truststoreFilePath"'#g' "$CLIENT_CONF_YAML"
        if [ $? -ne 0 ]; then
            echo "set security.ssl.truststore failed."
            return 1
        fi

        command -v sha256sum >/dev/null
        if [ $? -ne 0 ];then
            echo "sha256sum is not exist, it will produce security.cookie with date +%F-%H-%M-%s-%N."
            cookie=$(date +%F-%H-%M-%s-%N)
        else
            cookie="$(echo "${KEYTABPRINCEPAL}"| sha256sum | awk '{print $1}')"
        fi

        sed -i s/"security.cookie:".*/"security.cookie:"\ "${cookie}"/g "$CLIENT_CONF_YAML"
        if [ $? -ne 0 ]; then
            echo "set security.cookie failed."
            return 1
        fi
    fi
    return 0;
}

main()
{
    #check environment variable is set or not
    if [ -z ${FLINK_HOME+x} ]; then
        echo "errro: environment variables are not set."
        exit 1
    fi
    stty -echo
    read -rp "Enter password:" password
    stty echo
    echo


    KEYTABPRINCEPAL=$(grep "security.kerberos.login.principal" "$CLIENT_CONF_YAML" | awk '{print $2}')
    if [ -z "$KEYTABPRINCEPAL" ];then
        echo "please config security.kerberos.login.principal info first."
        exit 1
    fi


    #get input
    keystorePath="$KEYSTOREPATH"
    storePass="$password"
    keyPass="$password"

    #generate self signed CA
    createSelfSignedCA "$keystorePath" "$storePass" "$keyPass"
    if [ $? -ne 0 ]; then
        echo "create self signed ca failed."
        exit 1
    fi

    #generate keystore
    generateKeystore "$keystorePath" "$storePass" "$keyPass"
    if [ $? -ne 0 ]; then
        echo "create keystore failed."
        exit 1
    fi

    echo "generate keystore/truststore success."

    # set flink config
    configureFlinkConf "$keystorePath" "$storePass" "$keyPass"
    if [ $? -ne 0 ]; then
        echo "configure Flink failed."
        exit 1
    fi

    return 0;
}

#the start main
main "$@"

exit 0

Run the sh generate_keystore.sh <password> command. <password> is user-defined.

  • If <password> contains the special character $, use the following method to avoid the password being escaped: sh generate_keystore.sh 'Bigdata_2013'.
  • The password cannot contain #.
  • Before using the generate_keystore.sh script, run the source bigdata_env command in the client directory.
  • When the generate_keystore.sh script is used, the absolute paths of security.ssl.keystore and security.ssl.truststore are automatically filled in flink-conf.yaml. Therefore, you need to manually change the paths to relative paths as required. Example:
    • Change /opt/client/Flink/flink/conf//flink.keystore to security.ssl.keystore: ssl/flink.keystore.
    • Change /opt/client/Flink/flink/conf//flink.truststore to security.ssl.truststore: ssl/flink.truststore.
    • Create the ssl folder in any directory on the Flink client. For example, create the ssl folder in the /opt/client/Flink/flink/conf/ directory and save the flink.keystore and flink.truststore files to the ssl folder.
    • When you run the yarn-session or flink run -m yarn-cluster command, run the yarn-session.sh -t ssl -d or flink run -m yarn-cluster -yt ssl -d WordCount.jar command in the same directory as the ssl folder.