"This was because the "iv"
parameter in the pycrypto Cipher API is ignored in CTR mode. Instead, you
need to provide the data to the Counter object.
I don't know if I am being muddle-headed in thinking of the initial counter value as an IV, but I was a little annoyed with pycrypto. Couldn't it throw
an error if it's given an IV in CTR mode,"
THIS
API creators have to stop this bullshit of putting death traps in their code.
This is not about go RTFM, or "you're incompetent".
If you allow it to be used in a wrong manner, it's your liability as well.
If your IV sometimes goes into one field, but in another occasion goes in another field, THROW AN ERROR IF IT'S NOT USED CORRECTLY
It drives me a little crazy that implementations (and even some academics) have taken to calling the CTR nonce its "IV". There are particular requirements for IVs and particular requirements for nonces; they aren't the same thing.
That seems like a case of determining what the API should check for. An explicit check for e=1 seems stupid, the reasonable check would be to make sure that e was a valid exponent, which I believe means confirming that it is primes, which can have a non-trivial overhead (although in the case of RSA, the exponents are gennerally small enough that it doesn't matter.) The real question in this case is why the API let you select the exponent in the first place.
Hence, like I said: they should not have been near an API that had the letters R-S-A in it. They should've been near a very nice API with no configurable knobs to get wrong. The entire thing was part of an authenticated encryption scheme: they could've just use NaCl's `box` API and the entire thing would be two lines of code, give or take. Oh, and not utterly pointless ;-)
I don't know if I am being muddle-headed in thinking of the initial counter value as an IV, but I was a little annoyed with pycrypto. Couldn't it throw an error if it's given an IV in CTR mode,"
THIS
API creators have to stop this bullshit of putting death traps in their code.
This is not about go RTFM, or "you're incompetent".
If you allow it to be used in a wrong manner, it's your liability as well.
If your IV sometimes goes into one field, but in another occasion goes in another field, THROW AN ERROR IF IT'S NOT USED CORRECTLY