Introduction

Jobs might require variables for parameterization that hold secrets. We find a number of requirements for management of such variables, see JS7 - How to encrypt and decrypt

The preferred solution with JS7 is to use asymmetric keys, for details see JS7 - Encryption and Decryption.

  • Encryption and decryption can be performed directly by related jobs.
  • Encryption and decryption can be performed outside of JS7 products.
  • This includes that JS7 products have no knowledge of secret keys involved that potentially could be compromised by logging, database persistence etc.

For creation of Encryption Keys see JS7 - How to create X.509 Encryption Keys.

FEATURE AVAILABILITY STARTING FROM RELEASE 2.5.9
FEATURE AVAILABILITY STARTING FROM RELEASE 2.6.6

Download

The solution ships with JS7 Agents that can use encryption/decryption with shell jobs out-of-the-box.

In addition, the solution is provided for download to perform encryption and decryption outside of JS7 products.

Managing the Private Key and Certificate

Asymmetric encryption makes use of a Private Key and Certificate/Public Key that can be created in a number of ways:

  • Users can create a Certificate Signing Request (CSR) and ask their Certificate Authority (CA) to sign the CSR and to receive an X.509 Certificate. The Private Key and the X.509 Certificate allow to derive the Public Key.
  • User can create a self-issued X.509 Certificate, see JS7 - How to create X.509 Encryption Keys.
  • Users can create a Private Key and Certificate as explained in the next chapter.

Note: Private Keys can be protected using a passphrase that acts as a second factor when a human user will access the key: while the Private Key is in the file system, the passphrase is in the user's brains. However, this does not improve security for unattended processing: it's pointless to store a passphrase side-by-side with the Private Key in scripts or configuration files on the same media.

Step 1: Creating the Private Key and Certificate

The following step is performed on the server hosting the Agent that should decrypt secrets using the openssl utility from the command line.
Find more examples and explanations from JS7 - How to create X.509 Encryption Keys.

Example how to create Private Key and Certificate using ECDSA encryption
#!/bin/bash

# navigate to the Agent's <agent-data>/config/private directory
cd /var/sos-berlin.com/js7/agent/config/private

# create Private Key
#   for use with passphrase add: -passout pass:"secret"
openssl ecparam -name secp384r1 -genkey -noout -out agent.key

# create Certificate Signing Request
openssl req -new -sha512 -nodes -key agent.key -out agent.csr -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=Agent"

# create Certificate
#   for passphrase add: -passin pass:"secret"
openssl x509 -req -sha512 -days 1825 -signkey agent.key -in agent.csr -out agent.crt -extfile <(printf "keyUsage=critical,keyEncipherment,keyAgreement\n")
Example how to create Private Key and Certificate using RSA encryption
#!/bin/bash

# navigate to the Agent's <agent-data>/config/private directory
cd /var/sos-berlin.com/js7/agent/config/private

# create Private Key and Certificate Signing Request
#   for passphrase add: -passout pass:"secret"
openssl req -new -newkey rsa:4096 -sha256 -nodes -keyout agent.key -out agent.csr -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=Agent"

# create Certificate
#   for passphrase add: -passin pass:"secret"
openssl x509 -req -sha512 -days 1825 -signkey agent.key -in agent.csr -out agent.crt -extfile <(printf "keyUsage=critical,keyEncipherment,keyAgreement\n")

Step 2: Making the Certificate available

Copy the certificate file to the server(s) hosting the Agent(s) or 3rd-party components that should encrypt secrets:

Encryption

Usage

Invoking the script without arguments displays the usage clause:


Usage
Usage: js7_encrypt.sh [Options] [Switches]

  Options:
     --cert=<path-to-certificate>  | path to X.509 certificate or public key file used to encrypt the secret.
     --in=<secret>                 | secret that should be encrypted.
     --infile=<path-to-file>       | path to input file.
     --outfile=<path-to-file>      | path to output file that should be encrypted. 

  Switches:
     -h | --help                   | displays usage

Options

  • --cert
    • Specifies the path to a file that holds the CA signed or self-signed X.509 certificate. Alternatively the path to a file holding the public key can be specified.
  • --in
    • Specifies the input value that should be encrypted, typically a secret.
    • One of the options --in or --infile has to be specified.
  • --infile
    • Specifies the path to a file that should be encrypted.
    • One of the options --in or --infile has to be specified.
    • This option requires use of the --outfile option.
  • --outfile
    • Specifies the path to the output file that will be created holding the encrypted content of the input file.
    • The option is used if the --infile option is specified.

Switches

  • -h | --help
    • Displays usage.

Exit Codes

  • 1: argument errors
  • 2: processing errors

Return Values

The script writes output to the stdout channel that includes the following items separated by spaces:

  • encrypted symmetric key,
  • base64 encoded initialization vector,
  • encrypted secret or path to encrypted output file. 

Examples

The following examples illustrate typical use cases.

Encrypting Secret using Unix Shell

Example for Encryption using Unix Shell
result=$(./bin/js7_encrypt.sh --cert=agent.crt --in="secret")
echo "$result"

# encrypts the given secret using an Agent's X.509 certificate
# output includes the encrypted symmetric key, initialization vector and encrypted secret separated by space

Encrypting and forwarding Secret using Unix Shell in Jobs

Example for Encryption using Unix Shell
result=$(./bin/js7_encrypt.sh --cert=agent.crt --in="secret")
echo "new_var=$result" >> $JS7_RETURN_VALUES

# encrypts the given secret using an Agent's X.509 certificate
# output includes the encrypted symmetric key, initialization vector and encrypted secret separated by spaces
# output is stored to the "new_var" variable (key/value pair) that is made available for later jobs in the workflow

Encrypting File using Unix Shell

Example for Encryption using Unix Shell
echo "secret file" > /tmp/secret.txt
result=$(./bin/js7_encrypt.sh --cert=agent.crt --infile=/tmp/secret.txt --outfile=/tmp/secret.txt.encrypted)
echo "$result"

# encrypts the given file using an Agent's X.509 certificate and creates an encrypted output file
# output includes the encrypted symmetric key, initialization vector and path to encrypted file separated by spaces

Decryption

Usage

Invoking the script without arguments displays the usage clause:


Usage
Usage: js7_decrypt.sh [Options] [Switches]

  Options:
     --key=<path>                  | path to private key file for decryption.
     --key-password=<password>     | password for the private key.
     --in=<encrypted-result>       | encrypted symmetric key, initialization vector and path to encrypted file as returned by encryption.
     --infile=<path-to-file>       | path to encrypted input file.
     --outfile=<path-to-file>      | path to decrypted output file.

  Switches:
     -h | --help                   | displays usage

Options

  • --key
    • Specifies the path to the Private Key file that matches the X.509 Certificate or Public Key used for previous encryption.
    • The argument is required.
  • --key-password
    • Specifies the passphrase if the Private Key file indicated with the --key option is protected by a passphrase.
  • --in
    • Specifies the result of encryption that should be decrypted. The result includes the encrypted symmetric key, initialization vector and path to encrypted file separated by spaces as returned from the encryption step.
    • The argument is required. If the option --infile is specified, then its value takes precedence to the path specified with the --in option.
  • --infile
    • Specifies the path to an encrypted file that should be decrypted.
    • If this option is specified then its value takes precedence to the path specified with the --in option.
    • This option requires use of the --outfile option.
  • --outfile
    • Specifies the path to the output file that will be created holding the decrypted content of the input file.
    • The option is required if the --infile option is specified.

Switches

  • -h | --help
    • Displays usage.

Exit Codes

  • 1: argument errors
  • 2: processing errors

Return Values

The script writes output to the stdout channel that includes the following items:

  • decrypted secret or path to decrypted output file if the --infile and --outfile options are used.

Examples

The following examples illustrate typical use cases.

Decrypting Secret using Unix Shell

Example for Decryption using Unix Shell
# assumes that previous encryption created the "result" variable
# result=$(./bin/js7_encrypt.sh --cert=agent.crt --in="secret")

secret=$(./bin/js7_decrypt.sh \
    --key=agent.key \
    --in="$result")
echo "${secret}"

# decrypts the given encrypted secret using an Agent's private key
# encrypted symmetric key, initialization vector and encrypted secret are returned during encryption
# output includes the decrypted secret

Decrypting File using Unix Shell

Example for Decryption using Unix Shell
# assumes that previous encryption created the "result" variable
# result=$(./bin/js7_encrypt.sh --cert=agent.crt --infile=/tmp/secret.txt --outfile=/tmp/secret.txt.encrypted)

./bin/js7_decrypt.sh \
    --key=agent.key \
    --in="$result" \
    --infile=$(echo "${result}" | cut -d' ' -f 3) \
    --outfile=/tmp/secret.txt.decrypted
cat /tmp/secret.txt.decrypted

# decrypts the given encrypted file using an Agent's private key
# specifies the path to the encrypted input file from the result of encryption
# creates the decrypted output file

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