hash-pass.el

;; hash-pass http://hashapass.com/
(defvar hash-pass-password-wait-time "30 sec"
  "The default period to wait before erasing the password from the clipboard.
Must be compatible with `run-at-time'.")

(defun string->clipboard (string)
  "Copy STRING to system clipboard."
  (funcall interprogram-cut-function string))

(defun hash-pass ()
  "Generate strong password based on parameter and master password."
  (interactive)
  (let ((param (read-string "parameter: "))
        (password (read-passwd "master password: ")))
    (string->clipboard (trim
                        (shell-command-to-string
                         (format "echo -n %s | openssl dgst -sha1 -binary -hmac %s | openssl enc -base64 | cut -c 1-8" param password))))
    
    (run-at-time hash-pass-password-wait-time nil (lambda () (string->clipboard "")))
    (message "Generated hash has been copied to clipboard")))