Porting sh2pc code to ag2pc; Generating GCs

Question

Porting sh2pc code to ag2pc; Generating GCs

Closed this issue 4 years ago · 5 comments

emp-sh2pc seems to work with c code (probably generating the GC in the background) while emp-ag2pc seems to need a pre designed GC as an input. Is there a way to port emp-sh2pc to emp-sg2pc for malicious security? Or is it possible to recover the underlying circuit file generated by emp-sh2pc.

Finally, are there standard garbled circuit generators (from a high level language like C) compatible with emp-ag2pc.

Answer 1 · 2019-09-06T15:54:24.000Z

A tool in emp-tool's debug toolset provides this functionality. See this file:
https://github.com/emp-toolkit/emp-tool/blob/stable/test/gen_circuit.cpp

You will first write the function in this file, then you execute this debug program gen_circuit, which will generate a circuit file for the program.

Answer 2 · 2019-09-10T16:34:30.000Z

Thanks. This works great. Though I'm a bit lost as to how to deal with Integer array inputs to the circuits. For an emp::Integer array A, passing something like ((block*)A[0].bits) to the compute function doesn't seem to be working quite alright.

Answer 3 · 2019-09-10T16:40:29.000Z

I am not very sure which one is the compute(r) function. This file is an example related to the handling of integer, which could be helpful.

https://github.com/emp-toolkit/emp-tool/blob/stable/test/int.cpp

Answer 4 · 2019-09-10T16:58:00.000Z

Sorry I mean the circuit "compute function" (https://github.com/emp-toolkit/emp-tool/blob/stable/emp-tool/circuits/circuit_file.h). I have generated a circuit using gen_circuit. It does work alright for Integer inputs (example signature "cf.compute((block*)a.bits, (block*)b.bits, (block*)b.bits)" ). However, I'm now trying to extend the circuit for inputs where a, b & c are Integer arrays. The gen_circuit seems to be generating the appropriate circuit, however I'm a bit unsure of function parameters for "compute" function in this case.

Answer 5 · 2019-09-10T17:00:24.000Z

For integer arrays, you will need to manually "flatten" the input to a Bit array. Then pass "(block *)bitarray" to the function.

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On Tue, Sep 10, 2019 at 11:58 AM Nitin Agrawal ***@***.***> wrote: Hi, sorry I mean the circuit "compute function" ( https://github.com/emp-toolkit/emp-tool/blob/stable/emp-tool/circuits/circuit_file.h). I have generated a circuit using gen_circuit. It does work alright for Integer inputs (example signature "cf.compute((block*)a.bits, (block*)b.bits, (block*)b.bits)" ). However, I'm now trying to extend the circuit for inputs where a, b & c are Integer arrays. The gen_circuit seems to be generating the appropriate circuit, however I'm a bit unsure of function parameters for "compute" function in this case. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#13?email_source=notifications&email_token=AARKGCV4TOSLVQQWBIVFQJLQI7GZRA5CNFSM4IUHFTB2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD6LZLWQ#issuecomment-530027994>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AARKGCRPIIXJT55MWTMOGC3QI7GZRANCNFSM4IUHFTBQ> .