def keygen_only(pk_fname="pysnark_pk", vk_fname="pysnark_vk", do_print=True):
try:
pk_fname_file = open(pk_fname, "w")
vk_fname_file = open(vk_fname, "w")
except:
print("File open issue")
raise RuntimeError("*** File open issue")
sys.exit()
if pb.num_constraints() == 0:
# libsnark does not work in this case, add a no-op
pb.add_r1cs_constraint(
libsnark.R1csConstraint(libsnark.LinearCombination(),
libsnark.LinearCombination(),
libsnark.LinearCombination()))
cs = pb.get_constraint_system_pubs()
pubvals = pb.primary_input_pubs()
privvals = pb.auxiliary_input_pubs()
generator = (libsnark.zkgg_generator
if use_groth else libsnark.zk_generator)
keypair = generator(cs)
keypair.pk.write(pk_fname_file)
keypair.vk.write(vk_fname_file)
return (keypair.pk, keypair.vk)
def prove(do_keygen=True, do_write=True, do_print=True):
if pb.num_constraints() == 0:
# libsnark does not work in this case, add a no-op
pb.add_r1cs_constraint(
libsnark.R1csConstraint(libsnark.LinearCombination(),
libsnark.LinearCombination(),
libsnark.LinearCombination()))
cs = pb.get_constraint_system_pubs()
pubvals = pb.primary_input_pubs()
privvals = pb.auxiliary_input_pubs()
read_key = (libsnark.zkgg_read_key if use_groth else libsnark.zk_read_key)
generator = (libsnark.zkgg_generator
if use_groth else libsnark.zk_generator)
write_keys = (libsnark.zkgg_write_keys
if use_groth else libsnark.zk_write_keys)
prover = (libsnark.zkgg_prover if use_groth else libsnark.zk_prover)
verifier_strong_IC = (libsnark.zkgg_verifier_strong_IC
if use_groth else libsnark.zk_verifier_strong_IC)
write_proof = (libsnark.zkgg_write_proof
if use_groth else libsnark.zk_write_proof)
if do_print: print("*** Trying to read pysnark_ek", file=sys.stderr)
keypair = read_key("pysnark_ek", cs)
if not keypair:
if do_keygen:
if do_print:
print(
"*** No pysnark_ek or computation changed, generating keys...",
file=sys.stderr)
keypair = generator(cs)
write_keys(keypair, "pysnark_vk", "pysnark_ek")
else:
raise RuntimeError(
"*** No pysnark_ek or key is for different computation")
if do_print:
print("*** PySNARK: generating proof pysnark_log (" + "sat=" +
str(pb.is_satisfied()) + ", #io=" + str(pubvals.size()) +
", #witness=" + str(privvals.size()) + ", #constraint=" +
str(pb.num_constraints()) + ")",
file=sys.stderr)
proof = prover(keypair.pk, pubvals, privvals)
if do_write: write_proof(proof, pubvals, "pysnark_log")
if do_print:
print("*** Public inputs: " +
" ".join([str(pubvals.at(i)) for i in range(pubvals.size())]),
file=sys.stderr)
if do_print:
print("*** Verification status:",
verifier_strong_IC(keypair.vk, pubvals, proof),
file=sys.stderr)
return (keypair.vk, proof, pubvals)
def prove_only(pk_fname="pysnark_pk",
proof_log="pysnark_log",
pubvals_fname="pysnark_pubvals",
do_print=True):
try:
proof_log_file = open(proof_log, "w")
pk_fname_file = open(pk_fname, "r")
pubvals_file = open(pubvals_fname, "w")
except:
print("File open issue")
raise RuntimeError("*** File open issue")
sys.exit()
if pb.num_constraints() == 0:
# libsnark does not work in this case, add a no-op
pb.add_r1cs_constraint(
libsnark.R1csConstraint(libsnark.LinearCombination(),
libsnark.LinearCombination(),
libsnark.LinearCombination()))
cs = pb.get_constraint_system_pubs()
pubvals = pb.primary_input_pubs()
privvals = pb.auxiliary_input_pubs()
prover = (libsnark.zkgg_prover if use_groth else libsnark.zk_prover)
write_proof = (libsnark.zkgg_write_proof
if use_groth else libsnark.zk_write_proof)
read_key = libsnark.ZKProvingKey_read
#read_key = libsnark.zk_read_key
if do_print: print("*** Trying to read pk", file=sys.stderr)
keypair_pk = read_key(pk_fname_file)
if not keypair_pk:
raise RuntimeError("*** Unable to read proving key")
if do_print:
print("*** PySNARK: generating proof pysnark_log (" + "sat=" +
str(pb.is_satisfied()) + ", #io=" + str(pubvals.size()) +
", #witness=" + str(privvals.size()) + ", #constraint=" +
str(pb.num_constraints()) + ")",
file=sys.stderr)
proof = prover(keypair_pk, pubvals, privvals)
proof.write(proof_log_file)
proof_log_file.close()
make_pubvals_file(pubvals_file, pubvals)
#write_proof(proof, pubvals, proof_log)
return (proof, pubvals)
def privval(val):
pbv = libsnark.PbVariable()
pbv.allocate(pb)
pb.setval(pbv, val)
return libsnark.LinearCombination(pbv)
def one():
return libsnark.LinearCombination(1)
def zero():
return libsnark.LinearCombination()
inv.allocate(pb)
pb.setpublic(inv)
int = libsnark.PbVariable()
int.allocate(pb)
outv = libsnark.PbVariable()
outv.allocate(pb)
pb.setpublic(outv)
# create constraints
# let int=inv*(2*inv+1)
pb.add_r1cs_constraint(
libsnark.R1csConstraint(
libsnark.LinearCombination(inv),
libsnark.LinearCombination(inv) * 2 + libsnark.LinearCombination(1),
libsnark.LinearCombination(int)))
# let out=(int-1)*inv
pb.add_r1cs_constraint(
libsnark.R1csConstraint(
libsnark.LinearCombination(int) - libsnark.LinearCombination(1),
libsnark.LinearCombination(inv), libsnark.LinearCombination(outv)))
# create witnesses
pb.setval(inv, 3)
pb.setval(int, 21)
pb.setval(outv, 60)
cs = pb.get_constraint_system_pubs()