Update reference code to match main document

poc/Makefile

@@ -21,6 +21,11 @@ setup:
 test: pyfiles
 	sage test_oprf.sage
 
+examples: pyfiles
+	sage example_oprf.sage
+	sage example_voprf.sage
+	sage example_poprf.sage
+
 vectors: pyfiles
 	@echo "Removing vectors folder, if present"
 	@rm -rf vectors
@@ -34,4 +39,4 @@ clean:
 
 .PHONY: distclean
 distclean: clean
-	rm -rf vectors ascii
+	rm -rf vectors ascii

poc/example_oprf.sage

@@ -0,0 +1,53 @@
+#!/usr/bin/sage
+# vim: syntax=python
+
+"""Exemplifies a run of the OPRF protocol"""
+
+import os
+import sys
+
+try:
+    from sagelib.test_drng import TestDRNG
+    from sagelib.oprf \
+    import DeriveKeyPair, SetupOPRFServer, SetupOPRFClient, MODE_OPRF, \
+           oprf_ciphersuites, ciphersuite_p256_sha256
+
+except ImportError as err:
+    sys.exit("Try running `make setup && make clean pyfiles`. Full error: " + err)
+
+to_hex = lambda x: "".join(["{:02x}".format(i) for i in x])
+
+if __name__ == "__main__":
+    # Offline Setup
+    rng = TestDRNG('prng-seed'.encode('utf-8'))
+    suite = oprf_ciphersuites[ciphersuite_p256_sha256]
+    Ns = suite.group.scalar_byte_length()
+    info = b'info specific for this key'
+    seed = os.urandom(Ns)
+    skS, _ = DeriveKeyPair(MODE_OPRF, suite, seed, info)
+
+    client = SetupOPRFClient(suite)
+    server = SetupOPRFServer(suite, skS)
+
+    # Online Protocol
+    #
+    #   Client                                                Server(skS)
+    # -------------------------------------------------------------------
+    # blind, blindedElement = Blind(input)
+    input = b'alice in wonderland'
+    blind, blinded_element = client.blind(input, rng)
+    #                            blindedElement
+    #                              ---------->
+    #
+    #               evaluatedElement = BlindEvaluate(skS, blindedElement)
+    evaluated_element = server.blind_evaluate(blinded_element, rng)
+    #
+    #                            evaluatedElement
+    #                              <----------
+    #
+    # output = Finalize(input, blind, evaluatedElement)
+    output = client.finalize(input, blind, evaluated_element)
+    print("mode:", "OPRF")
+    print("suite:", suite.name)
+    print("input:", to_hex(input))
+    print("output:", to_hex(output))

poc/example_poprf.sage

@@ -0,0 +1,55 @@
+#!/usr/bin/sage
+# vim: syntax=python
+
+"""Exemplifies a run of the POPRF protocol"""
+
+import os
+import sys
+
+try:
+    from sagelib.test_drng import TestDRNG
+    from sagelib.oprf \
+    import DeriveKeyPair, SetupPOPRFServer, SetupPOPRFClient, MODE_POPRF, \
+           oprf_ciphersuites, ciphersuite_p256_sha256
+
+except ImportError as err:
+    sys.exit("Try running `make setup && make clean pyfiles`. Full error: " + err)
+
+to_hex = lambda x: "".join(["{:02x}".format(i) for i in x])
+
+if __name__ == "__main__":
+    # Offline Setup
+    rng = TestDRNG('prng-seed'.encode('utf-8'))
+    suite = oprf_ciphersuites[ciphersuite_p256_sha256]
+    Ns = suite.group.scalar_byte_length()
+    info = b'info specific for this key'
+    seed = os.urandom(Ns)
+    skS, pkS = DeriveKeyPair(MODE_POPRF, suite, seed, info)
+
+    client = SetupPOPRFClient(suite, pkS)
+    server = SetupPOPRFServer(suite, skS, pkS)
+
+    # Online Protocol
+    #
+    # Client(pkS, info)        <---- pkS ------       Server(skS, info)
+    #  -------------------------------------------------------------------
+    #  blind, blindedElement, tweakedKey = Blind(input, info)
+    input = b'alice in wonderland'
+    blind, blinded_element, tweaked_key = client.blind(input, info, rng)
+    #
+    #                             blindedElement
+    #                               ---------->
+    #
+    #        evaluatedElement, proof = BlindEvaluate(blindedElement, info)
+    evaluated_element, proof, _ = server.blind_evaluate(blinded_element, info, rng)
+    #
+    #                         evaluatedElement, proof
+    #                               <----------
+    #
+    #  output = Finalize(input, blind, evaluatedElement,
+    #                    blindedElement, proof, info, tweakedKey)
+    output = client.finalize(input, blind, evaluated_element, blinded_element, proof, info, tweaked_key)
+    print("mode:", "POPRF")
+    print("suite:", suite.name)
+    print("input:", to_hex(input))
+    print("output:", to_hex(output))

poc/example_voprf.sage

@@ -0,0 +1,52 @@
+#!/usr/bin/sage
+# vim: syntax=python
+
+"""Exemplifies a run of the VOPRF protocol"""
+
+import os
+import sys
+
+try:
+    from sagelib.test_drng import TestDRNG
+    from sagelib.oprf \
+    import DeriveKeyPair, SetupVOPRFServer, SetupVOPRFClient, MODE_VOPRF, \
+           oprf_ciphersuites, ciphersuite_p256_sha256
+
+except ImportError as err:
+    sys.exit("Try running `make setup && make clean pyfiles`. Full error: " + err)
+
+to_hex = lambda x: "".join(["{:02x}".format(i) for i in x])
+
+if __name__ == "__main__":
+    # Offline Setup
+    rng = TestDRNG('prng-seed'.encode('utf-8'))
+    suite = oprf_ciphersuites[ciphersuite_p256_sha256]
+    Ns = suite.group.scalar_byte_length()
+    info = b'info specific for this key'
+    seed = os.urandom(Ns)
+    skS, pkS = DeriveKeyPair(MODE_VOPRF, suite, seed, info)
+
+    client = SetupVOPRFClient(suite, pkS)
+    server = SetupVOPRFServer(suite, skS, pkS)
+
+    # Online Protocol
+    #
+    #   Client(pkS)                                       Server(skS,pkS)
+    # -------------------------------------------------------------------
+    # blind, blindedElement = Blind(input)
+    input = b'alice in wonderland'
+    blind, blinded_element = client.blind(input, rng)
+    #                            blindedElement
+    #                              ---------->
+    #
+    #            evaluatedElement, proof = BlindEvaluate(blindedElement)
+    evaluated_element, proof, _ = server.blind_evaluate(blinded_element, rng)
+    #                            <----------
+    #
+    # output = Finalize(input, blind, evaluatedElement,
+    #                   blindedElement, proof)
+    output = client.finalize(input, blind, evaluated_element, blinded_element, proof)
+    print("mode:", "VOPRF")
+    print("suite:", suite.name)
+    print("input:", to_hex(input))
+    print("output:", to_hex(output))