DD_Lock ver1.3 Copyright 1992 David Davis Introduction DD_Lock is a program that locks the computer keyboard and blanks the screen to provide security for the computer. It will activate after a adjustable number of minutes or if a hot-key is pressed. Once the keyboard is locked, either the password or the master password must be typed to make the keyboard functional again. If desired, DD_Lock can blank the screen after a shorter interval than that selected for keyboard locking. In this case, any key will restore the screen. DD_Lock is being distributed as a shareware product. Any use of this program, beyond testing and evaluation, requires that the program be registered. Testing should not take more than a few minutes, but periods up to a week are allowable. Complete information on how to register this program is located at the end of this document. As with any program, we can not guarantee that DD_Lock will not some day, some time, some where, with some combination of software, cause some one to lose valuable data or worse. We know of no such problems but USE DD_LOCK AT YOUR OWN RISK. We can not be held responsible for such problems. Quick Start For those people who never can never read the whole manual, here are the minimum instructions for operating DD_Lock. Reading the whole manual is, however, highly recommended. 1) Make sure DD_LOCK.COM is in the current directory. 2) Run LOCK_CFG.COM, this is the configuration program. The password and the master password should be modified at this time. 3) Now run DD_LOCK.COM and your computer is secure. (Running "DD_lock L" will cause the computer to start out in a locked state.) Purpose Personal computers have revolutionized the office by allowing large amounts of data to be available at a few key strokes. Unfortunately, that same data is also available to somebody wandering by and finding your computer unattended. This poses two threats. One, they could see confidential information and two, they could alter records. DD_Lock is designed to minimize the chance of these events happening. One hundred percent computer security is currently (and probably always will be) an unattainable goal. One could argue that removable hard drives and other hardware gadgets come close. Unfortunately all of these items are expensive, time consuming and provide no protection for all situations. For example, sometimes the user "will just be gone a second" from the keyboard. That "second" can often stretch to minutes and then hours before you get back to the unprotected computer. No computer security system can thwart a knowledgeable and determined hacker. Fortunately, such hackers are extremely rare. DD_Lock was designed as a compromise between user-friendliness, software compatibility and data security. DD_Lock is an inexpensive software solution to computer data security problems. DD_Lock performs two functions, it blanks the screen and it locks the keyboard. Technically speaking, it effectively locks the keyboard by preventing keystrokes from being processed by the computer. To unlock the keyboard all that is required is that you type in a password and hit the "Enter" key. DD_lock is designed to activate either after a programmable length of time has passed without any keys being pressed, or immediately if the proper hot-key combination is pressed. Ideally, anytime the computer operator leaves the computer he should hit the hot-key and secure the computer. If someone is approaching who should not see your sensitive data, then the hot- key can also be used to quickly blank the screen. In the case where the computer operator forgets to hit the hot-key, or gets sidetracked and leaves sensitive data displayed, DD_lock will automatically blank the screen and lock the keyboard to safeguard your data. Installation/Configuration Five items may be configured in DD_Lock; 2 passwords, 2 timers, and the hot-key. All of these are set by running the "LOCK_CFG.COM" program. Before running LOCK_CFG.COM make sure that the "DD_LOCK.COM" program is in the current directory. LOCK_CFG.COM does not need be in the current directory. Upon running "LOCK_CFG.COM", you will first be asked for a password. If this is the original installation or if you have not yet defined a master password, then all you need do is press the key. Otherwise type in either the current password or the current master password. If you wish to change the master password, then you must type in the master password when beginning the configuration program. Once a password is typed in, you will be given a list of options like these: 1) Time in minutes before screen blanks: 05 2) Time in minutes before keyboard locks: 10 3) Hot key combination to lock keyboard and blank screen immediately is: CTRL+ALT+Z 4) Password to unlock keyboard: þþþþþþþþþþþþþþþþþþþþ 5) Master Password to unlock keyboard: þþþþþþþþþþþþþþþþþþþþ 6) Save changes and quit. 7) Abandon changes and quit. To choose an option, type the number that appears before each description. 1) Time in minutes before screen blanks: 05 Choose option "1" to set the duration of keyboard inactivity that you wish to cause the screen to blank. The shorter the time selected the less likely the chance of leaving sensitive data on an unattended computer. Set the time to zero minutes if you do not wish do have the screen blank. This is handy for running presentations or demos where no keys are pressed for long periods of time, yet the screen is still being viewed. The ideal setting will vary with the individual and the software they are using. 2) Time in minutes before keyboard locks: 10 Option "2" is used to tell DD_Lock how long to wait, if no key is pressed, before locking the keyboard. Setting the keyboard to lock only after long periods of time, or disabling keyboard locking all together, decreases DD_Lock's effectiveness at preventing unauthorized computer activity. The ideal setting will vary with the individual and the software they are using. Note: In standard text modes, DD_Lock will place a message on the screen if a key is pressed while the keyboard is locked. This message will only appear if the screen is already been blanked by DD_Lock. Thus if screen blanking has been disabled or set to a time longer than the setting for the keyboard to lock, then the computer operator will have no indication of when the keyboard is locked (other, of course, than that his keystrokes have no effect, and that typing the password corrects the problem) 3) Hot key combination to lock keyboard and blank screen immediately is: CTRL+ALT+Z The default hot key to lock the keyboard and blank the screen is to hold down the and the keys, then, while still pressing the first two, press the "Z". If this keystroke combination is already being used, or if you simply would prefer to use a different one, you may do so. Valid hot keys are formed by holding some/none/all of the following keys {, , , } and then pressing any other key. While any other key will work, we recommend using the standard typewriter keys (A-Z) or function keys (-). The arrow keys, insert, delete, print screen, etc... keys can be used but are much more likely to cause conflicts with existing software. Also we recommend avoiding using the numbers on the numeric keypad (using the number keys above the letters work fine) as they act unpredictable especially when used with . The and keys are seldom used by most software and therefore make good one-key hot keys to allow DD_Lock to activate quickly. 4) Password to unlock keyboard: þþþþþþþþþþþþþþþþþþþþ Passwords for DD_Lock consist of up to twenty keystrokes with the last key being . Keystrokes can consist of any key on your keyboard. This means that the backspace key counts as a keystroke, not as a correction key, and if it is part of your password it must be typed each time same as any other key. We recommend sticking to the standard typewriter keys (A-Z) as they can be typed quickly, are easily remembered, and avoid the possibility of software incompatibilities. The reason we feel it important that you be able to type your password quickly is that sooner or later someone will be watching you as type in your password. Some other suggestions regarding passwords; Longer passwords are better than short ones. Avoid using names of family members, birthdays or nicknames. Don't write down your password. If you must write it down, don't write it on anything near the computer. Use two or more short unrelated words and type them without the spaces. IMPORTANT: PASSWORDS ARE CASE SENSITIVE. This means that upper case and lower case letters are different; i.e. "password" and "Password" are different passwords, because the latter starts with a capital "P". 5) Master Password to unlock keyboard: þþþþþþþþþþþþþþþþþþþþ Everything said above regarding passwords applies also to the master password. Master passwords are intended to be used by supervisors, technicians, or other people who need to have access to several computers while still allowing each computer to retain an individual password. Knowing the master password allows both passwords to be changed. The master password can only be changed if the operator knows the previous master password. 6) Save changes and quit. Once you have made your desired changes and wish to make them permanent, choose this option. If there is currently a copy of DD_Lock running on the computer, the configuration program will attempt to locate it and adapt it as well. If a currently memory resident version of DD_Lock is found you will be notified that it was found and updated. If no resident version is found you will also be informed of that. If you know that DD_Lock is running on the computer but the configure program fails to find and update it, then you should reboot the computer to make the changes active. We have never had the configuration program fail to find a memory resident version of DD_Lock, however, with the wide variety of memory managing software on the market it may happen. 7) Abandon changes and quit. If you decide you do not wish to change the configuration of DD_Lock, then you should choose this option. This will leave DD_Lock configured in the same manner as before "LOCK_CFG.COM" was run. Graphic Modes This version of DD_Lock is not designed to support graphics modes other than standard text modes and VGA. Most businesses and business applications use either the standard text modes or use the high quality graphics that VGA offers. By not supporting some lesser used CGA, EGA and Hercules hardware systems, we were able to create a smaller, faster keyboard locking program. If you find that you do use an application that runs in a graphics mode/hardware combination DD_Lock does not support, you can do one of the following: Disable or set to a longer time the screen blanking option. This avoids the problem by never asking DD_Lock to blank or restore the graphics screen. Screen blanking can then be re-enabled when finished running that application. or Run DD_Lock as normal. While DD_Lock does not support all possible graphic mode/hardware combinations, the worst that will normally happen is that DD_Lock will fail to restore or blank your screen properly. The application and the data it holds should not be affected in any way. If you are familiar with the application you were running it is often simple to have the application restore the screen. Changing screens, paging up/down, and redraw options all will probably work. Starting Locked DD_Lock can be run such that upon running, your computer starts out with the keyboard locked. To do this, at the command line type "DD_Lock.com L". While this may sometime come in handy the real reason for the option was so that it could be employed when the computer boots. d:\path\DD_Lock.com L By placing the above line in your AUTOEXEC.BAT file (where "d" and "path" are the drive and path DD_Lock is located at) your computer will start locked. This greatly enhances your computers security as otherwise anyone can evade DD_Lock by re- booting your computer. If you have DOS 4.0 or higher, use the following line in your CONFIG.SYS file as it provides greater security than installing DD_Lock via AUTOEXEC.BAT. Install=d:\path\DD_Lock.com L Regardless how "DD_Lock L" is loaded into your computer, DD_Lock will immediately lock the keyboard but is will not blank the screen. The screen is not blanked so that boot information may be viewed prior to unlocking the computer with the password. DD_Lock will, however, blank the screen except for a message saying the keyboard is locked, upon the user pressing any key. Note: Some keyboard utilities (usually keyboard speed-up utilities, or keyboard macro utilities) have the keyboard send a key as if one was pressed, if one of these programs is in your AUTOEXEC.BAT or CONFIG.SYS, then DD_Lock will respond as if the key were pressed. In other words, DD_Lock will restore the screen that was present when the first "key was pressed", regardless of whether that key was pressed by a human hand or some program. Screen Blanking and Screen Restoration DD_Lock will blank the screen, however that does not guarantee that it will stay blank. DD_Lock was designed to allow your computer to continue running its programs even if the screen is blanked and keyboard is locked. Some programs, particularly clock programs, write to the screen constantly. If you are running one of these programs do not be surprised if your "blank" screen has something on it. This should not cause any problems, but when DD_Lock restores the screen, it restores it to the screen that it blanked. Anything your program outputs to the screen while the screen is being kept blank, may be lost. The exception to this is if you are using an application that does not run in a standard text mode and you have a VGA card in your computer. In this case, when active, DD_Lock will keep the screen perfectly blank until it restores the screen, and then it will update the screen to include any changes made while it was "blank". While this allows large, complicated, processor intensive applications to preserve their screen output, it disables the ability to place the "Computer Locked" message on screen where it would otherwise be able to. Customizing and Support User-friendliness versus functionality is only one of the tradeoffs being balanced in this program. We are proud of this program and believe it to be the best balance of size, speed and power for most users. You or your company, may however, have special needs. Particular software/hardware requirements, additional password levels, added security measures, all might make DD_Lock a better program for your circumstances. At D.C.D. Computing, we specialize in custom software. Small changes in one of our existing programs are easily accomplished, and if it is a common request, there would be little or no additional cost. We also can write completely original programs in virtually all computing fields. Contact us for more details. Furthermore, if you have any trouble, questions or suggestions about any of our products, please feel free to contact us. We can be reached by mail, phone, fax, or modem. Our address is: DCD Computing 2974 S. Country Club Way Tempe, AZ 85282 Our phone number is (602) 897-8653. To send the a fax, dial that same number (602) 897-8653. Once our switchboard has answered, dial extension 22 and send your fax. For modem communications, call our BBS. Dial our number (602) 897-8653, and dial extension 33 once our switchboard has answered. You can have your modem dial our number by telling it to dial 1-602-897-8653,,,,,,,33. The commas before the 33 tell your modem to pause. The number of commas may need to be adjusted to insure the pause was long enough for our switchboard to answer. Order Information To register DD_Lock, send a check to DCD Computing for $17.50 per computer DD_Lock will be used on. Discounts are available for quantity purchases. Please contact us for details. For your (and our) convenience, just fill in this page and send it with your check. Your Name:_________________________________________________ Company Name:_________________________________________________ Street Address:_________________________________________________ City, State:_________________________________________________ Zip Code:___________________________ Type of Computer(s): ___________________________________________ Graphics Adapter(s): ___________________________________________ Size Disks Used: _____________________________ _____ Please send me information on other products by DCD Computing. _____ Please send me only information concerning updates to DD_Lock. _____ Please save the our forests by not sending me any information that isn't going to be read anyway. Number of computers your company has ___________ x $17.50 ============== Total due ___________ Note: If in Arizona, please include an additional 6.7% for sales tax. Please send to: DCD Computing 2974 S. Country Club Way Tempe, Az 85282