SSLES

Single Secret Leader Election Snark (Block Proposer privacy Protocol using ZKSnarks):

Public parameters:

• A public random number m (emitted by the random beacon).
• The roothash of all the participants’ public keys: rh.
• h = hash(signed(m))

Secret parameters:

• Sign the message m by all participants: signed(m)
• The signer’s public key: pk
• Merkle path: mp

Protocol

• Generate N signature pairs pub/priv pair, we generate a SNARK (since participants have to send proof that they are eligible).
• We choose one party hash h to be the block proposer.
• The party that was chosen will publish the sig that proves they are the right person.
• The other parties verify the sig to verify if the msg m was actually signed by the corresponding private key.

Checks performed by the ZK-SNARK:

1. The public key belongs to one of the participants: the Merkle path mp leads from the public key pk to the root hash rh.

2. Signed(m) checks out against the public key pk and the random number m.

3. Hash(signed(m)) given in the public parameters is the hash of signed(m) given in the secret parameters.

4. Signed(m) in the secret parameters is the same `m given in the public parameters.

Build instructions

Fetch dependencies from their GitHub repos:

git clone git@github.com:HarryR/ethsnarks.git
cd ethsnarks
make

in depends folder do

git clone https://github.com/scipr-lab/libsnark.git
 mkdir build && cd build


   LD_LIBRARY_PATH=/usr/local/opt/openssl/lib:"${LD_LIBRARY_PATH}"                    
CPATH=/usr/local/opt/openssl/include:"${CPATH}"                                    
PKG_CONFIG_PATH=/usr/local/opt/openssl/lib/pkgconfig:"${PKG_CONFIG_PATH}"          
export LD_LIBRARY_PATH CPATH PKG_CONFIG_PATH       

CPPFLAGS=-I/usr/local/opt/openssl/include LDFLAGS=-L/usr/local/opt/openssl/lib PKG_CONFIG_PATH=/usr/local/opt/openssl/lib/pkgconfig cmake -DWITH_PROCPS=OFF -DWITH_SUPERCOP=OFF ..

make

In the SSLES folder:

Create the Makefile:

$ mkdir build && cd build

LD_LIBRARY_PATH=/usr/local/opt/openssl/lib:"${LD_LIBRARY_PATH}"                    
CPATH=/usr/local/opt/openssl/include:"${CPATH}"                                    
PKG_CONFIG_PATH=/usr/local/opt/openssl/lib/pkgconfig:"${PKG_CONFIG_PATH}"          
export LD_LIBRARY_PATH CPATH PKG_CONFIG_PATH       

CPPFLAGS=-I/usr/local/opt/openssl/include LDFLAGS=-L/usr/local/opt/openssl/lib PKG_CONFIG_PATH=/usr/local/opt/openssl/lib/pkgconfig cmake -DWITH_PROCPS=OFF -DWITH_SUPERCOP=OFF ..

Then, to compile the library, tests, and profiling harness, run this within the build directory:

$ make