Not directly related but I wrote an exchange rate calculator for propmodule.com and I thought I would share the code with you.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
PropModule Now has over voltage protection. I have added a 3.9V Zener to the supply line.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
A zener will not protect the prop if it cannot handle the current. For this you also require a suitable resistor and this cannot be calculated without knowing what voltage limits you will handle. Depending on what you are trying to do, try the LM1117-3V3 voltage regulator. The TO252 package is smt but you can easily solder these.
Anyone can crack anything given the resources. But disclosing any methods here only serves to defeat the purpose. It depends on the benefit to the cracker. Just look at Chip's Interpreter. No-one really bothered until Chip threw down the gauntlet and Hippy took up the challenge.
You have provided a great method to at least in part stop those with lesser knowledge and I congratulate you for this.
I'll PM you with some more ideas.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Links to other interesting threads:
The zener I put in can handle 1.5W It will not last forever if you abuse it and apply 12v. But it only costs me $0.20 so I threw it in as a safety feature.
I don't want to put on linear voltage regulators because they are terribly inefficient and when on battery power efficiency is ideal. For this reason my second module I have now built is a 3.3V dual source switching regulator. It is 97% efficient and can function between 3.5V and 14V(it will work down to 2.7V but the output voltage will be below 3.3V) It is 1"long 6pin module with Wall and Battery In, Unregulated Voltage Out,Regulated Voltage Out,GND,On Battery.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
Kind of reminds me of a bicycle lock. The point isn't to make it completely impenetrable, just inconvenient - which is sounds like it does. I suspect that no data is safe in the hands of hippy, but it would probably be annoying enough for me to give up. The discussion around monitoring current flow thru the pull up resistor is pretty interesting.
I have to wonder, though, how many Propeller developers have been hiding in fear of EEPROM thieves. If someone stole my eeprom, I'd probably just be flattered. Cool idea, though!
Even for those like you that don't need the security it is a very convient module. eeprom, crystal, prop in a pack just slightly bigger then the dip pack of the prop. even a uSD card reader and real time clock with battery. The price at $60CAN[noparse][[/noparse]$46.64US] is not overly unreasonable for all that.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
and I will give $5 off to the next 5 modules I sell if you reference the fact I offered the discount.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
Nick McClick said...
The point isn't to make it completely impenetrable, just inconvenient - which is sounds like it does.
Although that comes down to what the module is advertised as providing. The main point through the entire thread is that the module is not / may not be "secure", although I think everyone recognises there are degrees of security.
It is perhaps a semantic problem of using "secure" as an absolute term. In terms of making it more inconvenient to access the code and a deterrent to doing so that's not in doubt. Does it make code as secure as a user may hope for or expect ? Hard to say if it is "security through obscurity", it may be brilliant, it may have a fundamental but unseen flaw which can be easily exploited later.
With all the best technological efforts in the world one still has to assess how secure a product is if one can take a wood chisel to its side and a hard tap splits it in two and exposes the then unprotected innards. Even if that works it may still be "secure enough" for many users, but not for others.
Ultimately it comes down ( as discussed in other threads on protecting Propeller code ) to does the mechanism used offer enough protection against the perceived threats it must be immune from.
I expect there will be similar intellectual debate and analysis on whatever security the Prop II offers for protecting code.
Comments
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
Anyone can crack anything given the resources. But disclosing any methods here only serves to defeat the purpose. It depends on the benefit to the cracker. Just look at Chip's Interpreter. No-one really bothered until Chip threw down the gauntlet and Hippy took up the challenge.
You have provided a great method to at least in part stop those with lesser knowledge and I congratulate you for this.
I'll PM you with some more ideas.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:
· Home of the MultiBladeProps:· SixBladeProp, TriBladeProp
· Prop Tools under Development or Completed (Index)
· Emulators (Micros eg Altair, and Terminals eg VT100) - index
· Search the Propeller forums (via Google)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm
I don't want to put on linear voltage regulators because they are terribly inefficient and when on battery power efficiency is ideal. For this reason my second module I have now built is a 3.3V dual source switching regulator. It is 97% efficient and can function between 3.5V and 14V(it will work down to 2.7V but the output voltage will be below 3.3V) It is 1"long 6pin module with Wall and Battery In, Unregulated Voltage Out,Regulated Voltage Out,GND,On Battery.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
I have to wonder, though, how many Propeller developers have been hiding in fear of EEPROM thieves. If someone stole my eeprom, I'd probably just be flattered. Cool idea, though!
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Gadget Gangster - Share your Electronic Projects - Sign up as a Designer and get a free 4-pack of Project Boards!
Even for those like you that don't need the security it is a very convient module. eeprom, crystal, prop in a pack just slightly bigger then the dip pack of the prop. even a uSD card reader and real time clock with battery. The price at $60CAN[noparse][[/noparse]$46.64US] is not overly unreasonable for all that.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
Although that comes down to what the module is advertised as providing. The main point through the entire thread is that the module is not / may not be "secure", although I think everyone recognises there are degrees of security.
It is perhaps a semantic problem of using "secure" as an absolute term. In terms of making it more inconvenient to access the code and a deterrent to doing so that's not in doubt. Does it make code as secure as a user may hope for or expect ? Hard to say if it is "security through obscurity", it may be brilliant, it may have a fundamental but unseen flaw which can be easily exploited later.
With all the best technological efforts in the world one still has to assess how secure a product is if one can take a wood chisel to its side and a hard tap splits it in two and exposes the then unprotected innards. Even if that works it may still be "secure enough" for many users, but not for others.
Ultimately it comes down ( as discussed in other threads on protecting Propeller code ) to does the mechanism used offer enough protection against the perceived threats it must be immune from.
I expect there will be similar intellectual debate and analysis on whatever security the Prop II offers for protecting code.