Made permutation a responsibility of cmix in the realtime phase.

2 files changed, 20 insertions, 1 deletions

diff --git a/libcmix/cmix.c b/libcmix/cmix.c
index 2ba5fd9..149bc7d 100644
--- a/libcmix/cmix.c
+++ b/libcmix/cmix.c
@@ -205,6 +205,25 @@ enum cmix_error permute_and_multiply_encrypted_s(struct CMixContext const* ctx,
 	return no_error;
 }
 
+enum cmix_error permute_and_multiply_s(struct CMixContext const* ctx, char** out_buffer, char const** message, size_t nr_elements) {
+	size_t el_size = get_group_element_array_size(ctx);
+	
+	for(size_t i = 0; i < nr_elements; ++i) {
+		unsigned int new_pos = ctx->permutation[i];
+		
+		GroupElement message_el = ctx->api.array_to_element(message[i], el_size, false);
+		GroupElement mult = ctx->api.multiply(message_el, ctx->s[new_pos], false);
+		
+		element_to_buffer(ctx, out_buffer[new_pos], mult);
+		
+		ctx->api.free_group_element(message_el);
+		ctx->api.free_group_element(mult);
+	}
+	
+	return no_error;
+}
+
+
 enum cmix_error multiply_s(struct CMixContext const* ctx, char* out_buffer, char const* message, size_t index) {
 	size_t el_size = get_group_element_array_size(ctx);
 	
diff --git a/libcmix/cmix.h b/libcmix/cmix.h
index f3d071d..689906c 100644
--- a/libcmix/cmix.h
+++ b/libcmix/cmix.h
@@ -87,7 +87,7 @@ enum cmix_error encrypt_r_and_multiply(struct CMixContext const* ctx, char* rand
 
 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);
 
-enum cmix_error multiply_s(struct CMixContext const* ctx, char* out_buffer, char const* message, size_t index);
+enum cmix_error permute_and_multiply_s(struct CMixContext const* ctx, char** out_buffer, char const** message, size_t nr_elements);
 
 enum cmix_error get_key_exchange_value(struct CMixContext const* ctx, char* buffer, GroupElement priv_element);