The Precomputation precomputation step is now done on batch level.

4 files changed, 83 insertions, 75 deletions

diff --git a/libcmix/cmix.c b/libcmix/cmix.c
index 149bc7d..9c983f0 100644
--- a/libcmix/cmix.c
+++ b/libcmix/cmix.c
@@ -138,41 +138,50 @@ enum cmix_error set_network_key(struct CMixContext* ctx, char const* buffer, siz
 	return no_error;
 }
 
-enum cmix_error encrypt_r(struct CMixContext const* ctx, char* random_buffer, char* message_buffer, size_t index) {
-	GroupElement random_element;
-	GroupElement message_element;
+enum cmix_error encrypt_r(struct CMixContext const* ctx, char** random_buffer, char** message_buffer, size_t nr_elements) {
 	
-	ctx->api.encrypt(&random_element, &message_element, ctx->r[index], ctx->network_key);
+	for(size_t i = 0; i < nr_elements; ++i) {
+		GroupElement random_element;
+		GroupElement message_element;
+	
+		ctx->api.encrypt(&random_element, &message_element, ctx->r[i], ctx->network_key);
 	
-	element_to_buffer(ctx, random_buffer, random_element);
-	element_to_buffer(ctx, message_buffer, message_element);
+		element_to_buffer(ctx, random_buffer[i], random_element);
+		element_to_buffer(ctx, message_buffer[i], message_element);
+		
+		ctx->api.free_group_element(random_element);
+		ctx->api.free_group_element(message_element);
+	}
 	
 	return no_error;
 }
 
-enum cmix_error encrypt_r_and_multiply(struct CMixContext const* ctx, char* random_buffer, char* message_buffer, const char* random_element, const char* message_element, size_t index) {
-	GroupElement enc_random_element;
-	GroupElement enc_message_element;
-	
-	ctx->api.encrypt(&enc_random_element, &enc_message_element, ctx->r[index], ctx->network_key);
-	
-	size_t el_size = get_group_element_array_size(ctx);
-	
-	GroupElement other_random_element = ctx->api.array_to_element(random_element, el_size, true);
-	GroupElement other_message_element = ctx->api.array_to_element(message_element, el_size, true);
+enum cmix_error encrypt_r_and_multiply(struct CMixContext const* ctx, char** random_buffer, char** message_buffer, const char** random_element, const char** message_element, size_t nr_elements) {
 	
-	GroupElement new_random_element = ctx->api.multiply(enc_random_element, other_random_element, true);
-	GroupElement new_message_element = ctx->api.multiply(enc_message_element, other_message_element, true);
-	
-	element_to_buffer(ctx, random_buffer, new_random_element);
-	element_to_buffer(ctx, message_buffer, new_message_element);
+	for(size_t i = 0; i < nr_elements; ++i) {
+		GroupElement enc_random_element;
+		GroupElement enc_message_element;
+		
+		ctx->api.encrypt(&enc_random_element, &enc_message_element, ctx->r[i], ctx->network_key);
+		
+		size_t el_size = get_group_element_array_size(ctx);
 		
-	ctx->api.free_group_element(enc_random_element);
-	ctx->api.free_group_element(enc_message_element);
-	ctx->api.free_group_element(other_random_element);
-	ctx->api.free_group_element(other_message_element);
-	ctx->api.free_group_element(new_random_element);
-	ctx->api.free_group_element(new_message_element);
+		GroupElement other_random_element = ctx->api.array_to_element(random_element[i], el_size, true);
+		GroupElement other_message_element = ctx->api.array_to_element(message_element[i], el_size, true);
+		
+		GroupElement new_random_element = ctx->api.multiply(enc_random_element, other_random_element, true);
+		GroupElement new_message_element = ctx->api.multiply(enc_message_element, other_message_element, true);
+		
+		element_to_buffer(ctx, random_buffer[i], new_random_element);
+		element_to_buffer(ctx, message_buffer[i], new_message_element);
+			
+		ctx->api.free_group_element(enc_random_element);
+		ctx->api.free_group_element(enc_message_element);
+		ctx->api.free_group_element(other_random_element);
+		ctx->api.free_group_element(other_message_element);
+		ctx->api.free_group_element(new_random_element);
+		ctx->api.free_group_element(new_message_element);
+	}
 	
 	return no_error;
 }
diff --git a/libcmix/cmix.h b/libcmix/cmix.h
index 689906c..53a3d99 100644
--- a/libcmix/cmix.h
+++ b/libcmix/cmix.h
@@ -81,9 +81,9 @@ size_t get_group_element_array_size(struct CMixContext const* ctx);
 
 enum cmix_error set_network_key(struct CMixContext* ctx, char const* buffer, size_t len);
 
-enum cmix_error encrypt_r(struct CMixContext const* ctx, char* random_buffer, char* message_buffer, size_t index);
+enum cmix_error encrypt_r(struct CMixContext const* ctx, char** random_buffer, char** message_buffer, size_t nr_elements);
 
-enum cmix_error encrypt_r_and_multiply(struct CMixContext const* ctx, char* random_buffer, char* message_buffer, char const* random_element, char const* message_element, size_t index);
+enum cmix_error encrypt_r_and_multiply(struct CMixContext const* ctx, char** random_buffer, char** message_buffer, char const** random_element, char const** message_element, size_t nr_elements);
 
 enum cmix_error permute_and_multiply_encrypted_s(struct CMixContext const* ctx, char** random_buffer, char** message_buffer, char const** random_element, char const** message_element, size_t nr_elements);
 
diff --git a/node/node.cpp b/node/node.cpp
index a6ad1e1..b29a873 100644
--- a/node/node.cpp
+++ b/node/node.cpp
@@ -176,28 +176,27 @@ void Node::start_precomputation() {
 	
 	cmix_proto::PrePre prepre;
 	
-	for(size_t i = 0; i < cmix_ctx.nr_participants; ++i) {
-		prepre.add_m_er();
-		prepre.add_r_er();
+	size_t len = get_group_element_array_size(&cmix_ctx);
+	std::vector<char*> r_er(cmix_ctx.nr_participants, nullptr);
+	std::vector<char*> m_er(cmix_ctx.nr_participants, nullptr);
 	
-		size_t len = get_group_element_array_size(&cmix_ctx);
-		
-		prepre.mutable_r_er(i)->resize(len);
-		prepre.mutable_m_er(i)->resize(len);
-		
-		{
-			std::stringstream ss;
-			ss << "r: ";
-			std::string r = to_string(cmix_ctx.r[i], cmix_ctx);
-			for(auto&& c : r) {
-				ss << "\\" << std::setw(3) << std::setfill('0') << std::oct << (unsigned int) c;
-			}
-			BOOST_LOG_TRIVIAL(trace) << ss.str();
-		} 
+	for(size_t i = 0; i < cmix_ctx.nr_participants; ++i) {
+		std::string* r = prepre.add_r_er();
+		r->resize(len);
+		r_er[i] = &(*r)[0];
 		
-		if(encrypt_r(&cmix_ctx, &(*prepre.mutable_r_er(i))[0], &(*prepre.mutable_m_er(i))[0], i) != no_error) {
-			exit(-1);
-		}
+		std::string* m = prepre.add_m_er();
+		m->resize(len);
+		m_er[i] = &(*m)[0]; 
+	}
+	
+	if(encrypt_r(
+		&cmix_ctx,
+		r_er.data(),
+		m_er.data(),
+		cmix_ctx.nr_participants
+	) != no_error) {
+		exit(-1);
 	}
 	
 	BOOST_LOG_TRIVIAL(trace) << "Sending prepre message: " << prepre.ShortDebugString();
diff --git a/node/node_node.cpp b/node/node_node.cpp
index 8faa4cf..f6e5071 100644
--- a/node/node_node.cpp
+++ b/node/node_node.cpp
@@ -20,36 +20,36 @@ cmix_proto::PrePre fill_precomputation_pre_message(CMixContext& ctx, T const& rs
 	
 	cmix_proto::PrePre prepre;
 	
+	size_t len = get_group_element_array_size(&ctx);
+	std::vector<char*> r_ers(ms.size(), nullptr);
+	std::vector<char*> m_ers(ms.size(), nullptr);
+	std::vector<char const*> rsv(ms.size(), nullptr);
+	std::vector<char const*> msv(ms.size(), nullptr);
+	
 	for(size_t i = 0; i < ms.size(); ++i) {
-		prepre.add_m_er();
-		prepre.add_r_er();
+		std::string* r = prepre.add_r_er();
+		r->resize(len);
+		r_ers[i] = &(*r)[0];
 	
-		size_t len = get_group_element_array_size(&ctx);
-		
-		prepre.mutable_m_er(i)->resize(len);
-		prepre.mutable_r_er(i)->resize(len);
-		
-		{
-			std::stringstream ss;
-			ss << "r: ";
-			std::string r = to_string(ctx.r[i], ctx);
-			for(auto&& c : r) {
-				ss << "\\" << std::setw(3) << std::setfill('0') << std::oct << (unsigned int) c;
-			}
-			BOOST_LOG_TRIVIAL(trace) << ss.str();
-		} 
+		std::string* m = prepre.add_m_er();
+		m->resize(len);
+		m_ers[i] = &(*m)[0];
 		
-		if(encrypt_r_and_multiply(
-			&ctx, 
-			&(*prepre.mutable_r_er(i))[0],
-			&(*prepre.mutable_m_er(i))[0],
-			rs.Get(i).data(),
-			ms.Get(i).data(),
-			i
-		) != no_error) {
-			exit(-1);
-		}
+		rsv[i] = rs.Get(i).data();
+		msv[i] = ms.Get(i).data();
 	}
+	
+	if(encrypt_r_and_multiply(
+		&ctx, 
+		r_ers.data(),
+		m_ers.data(),
+		rsv.data(),
+		msv.data(),
+		ms.size()
+	) != no_error) {
+		exit(-1);
+	}
+	
 	return prepre;
 }