OpenSSL Encryption & Decryption

decrypt.sh

#!/bin/bash

encryptedPayloadFile=""
privateKeyFile=""
outputFile=""

function diy() {
    cat <<EOF
    openssl enc -base64 -A -d -in payload.cipher.base64 -out payload.cipher

    openssl rsautl -decrypt -inkey ssl/client.key -in payload.cipher -out payload.txt
EOF
}

function usage() {
    # ./decrypt.sh -p "payload.cipher.base64" -k "ssl/client.key" -o "payload.txt"
    cat <<EOF
Usage: $0 [ -p PAYLOAD ] [ -k PRIVATE_KEY ] [ -o OUTPUT ] [ -h HELP ]
    Options:
        -p    [Payload] file to decrypt.
        -k    [Private Key] file for decryption.
        -o    [Output] file for encrypted payload. (optional)
        -h    [Help] Show usage
EOF
}

function abort() {
    errcho "Usage: $0 [ -p PAYLOAD ] [ -k PRIVATE_KEY ] [ -o OUTPUT ] [ -h HELP ]" 1>&2
    exit 1
}

function errcho() { 
    >&2 echo $@; 
}

while getopts ":p:k:o:h" options
do
case $options in
    p)
        encryptedPayloadFile="$OPTARG"
        ;;
    k)
        privateKeyFile="$OPTARG"
        ;;
    o)
        outputFile="$OPTARG"
        ;;
    h)
        usage
        exit 0
        ;;
    :)
        errcho "Option: [ -${OPTARG} ] requires an argument."
        abort
        ;;
    *)
        abort
        ;;
    esac
done

if [ -z "$encryptedPayloadFile" ]; then
    errcho "[ -p PAYLOAD ] is required"
    exit 1
fi

if [ ! -f "$encryptedPayloadFile" ]; then
    errcho "Encrypted payload file: '$encryptedPayloadFile' doesn't exist."
    exit 1
fi

if [ -z "$privateKeyFile" ]; then
    errcho "[ -k KEY ] is required"
    exit 1
fi

if [ ! -f "$privateKeyFile" ]; then
    errcho "Public key file: '$privateKeyFile' doesn't exist."
    exit 1
fi

openssl enc -base64 -A -d -in $encryptedPayloadFile -out /tmp/payload.cipher

if [ "$outputFile" ]; then
    openssl rsautl -decrypt -inkey $privateKeyFile -in /tmp/payload.cipher -out $outputFile
else 
    openssl rsautl -decrypt -inkey $privateKeyFile -in /tmp/payload.cipher
fi

exit 0

encypt.sh

#!/bin/bash

payload=""
publicKey=""
outputFile=""

function diy() {
    cat <<EOF
    printf %s 'jdoe:21331157' > payload.txt

    openssl rsautl -encrypt -inkey ssl/client.pub -pubin -in payload.txt -out payload.cipher

    openssl enc -base64 -A -in payload.cipher -out payload.cipher.base64
EOF
}

function usage() {
    # ./encrypt.sh -p "jdoe:21331157" -k "ssl/client.pub" -o "payload.cipher.base64"
    cat <<EOF
Usage: $0 [ -p PAYLOAD ] [ -k PUBLIC_KEY ] [ -o OUTPUT ]
    Options:
        -p    [Payload] to be encrypted.
        -k    [Public key] file for encryption.
        -o    [Output] file for encrypted payload. (optional)
        -h    [Help] Show usage.
EOF
}

function abort() {
    errcho "Usage: $0 [ -p PAYLOAD ] [ -k PUBLIC_KEY ] [ -o OUTPUT ] [ -h HELP ]" 1>&2
    exit 1
}

function errcho() { 
    >&2 echo $@; 
}

while getopts ":p:k:o:h" options
do
case $options in
    p)
        payload="$OPTARG"
        ;;
    k)
        publicKey="$OPTARG"
        ;;
    o)
        outputFile="$OPTARG"
        ;;
    h)
        usage
        exit 0
        ;;
    :)
        errcho "Option: [ -${OPTARG} ] requires an argument."
        abort
        ;;
    *)
        abort
        ;;
    esac
done

if [ -z "$payload" ]; then
    errcho "[ -p PAYLOAD ] is required"
    exit 1
fi

if [ -z "$publicKey" ]; then
    errcho "[ -k PUBLIC_KEY ] is required"
    exit 1
fi

if [ ! -f "$publicKey" ]; then
    errcho "Public key file: '$publicKey' doesn't exist."
    exit 1
fi

printf "%s" $payload > /tmp/payload.txt

openssl rsautl -encrypt -inkey $publicKey -pubin -in /tmp/payload.txt -out /tmp/payload.cipher

if [ "$outputFile" ]; then
    openssl enc -base64 -A -in /tmp/payload.cipher -out $outputFile
else 
    openssl enc -base64 -A -in /tmp/payload.cipher
fi

rm -f /tmp/payload.txt
rm -f /tmp/payload.cipher

exit 0