Functions to create encrypted files with a password using openssl and prompting for password

create_and_read_encrypted_files.R

#' Create Encrypted Files
create_encrypted_height_weight_medications <- function() {

  # load files to be encrypted
  dfs <-
    list(
      file1 = "sensitive_data/file1.xlsx",
      file2 = "sensitive_data/file2.xlsx",
      file3 = "sensitive_data/file3.xlsx"
    ) %>% purrr::map(readxl::read_excel)

  # serialize data
  dfs_serialized <- dfs %>% serialize(NULL)

  # query key from user
  key <- sha256(charToRaw(rstudioapi::askForPassword("Enter encryption passphrase:")))

  # encrypt data
  encrypted_dfs <- aes_cbc_encrypt(dfs_serialized, key = key)

  # save in encrypted data store
  saveRDS(
    encrypted_dfs,
    file.path(
      'sensitive_data/encrypted_r_readable/'
    ), 'encrypted_dfs.rds')
  )
}

#' Read Encrypted Data
read_height_weight_medications <- function() {

  # if the encryption key is already defined in the environment, use that;
  # otherwise query the user for the encryption passphrase.
  if (! exists('encryption_key')) {
    encryption_key <-
      openssl::sha256(charToRaw(rstudioapi::askForPassword("Enter encryption passphrase:")))

    assign('encryption_key', encryption_key, envir = globalenv())
  }

  # load the encrypted data
  encrypted_dfs <- readRDS(
    'sensitive_data/encrypted_r_readable/encrypted_dfs.rds'
  )

  # decrypt and de-serialize the data into a list of dataframes
  dfs <- unserialize(openssl::aes_cbc_decrypt(encrypted_dfs, key = encryption_key))

  return(dfs)
}