adds missing BUILD rules, updates grpc deps version
diff --git a/WORKSPACE b/WORKSPACE
index ac13e33..bb3c6da 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -53,10 +53,10 @@
 # gRPC
 http_archive(
     name = "com_github_grpc_grpc",
-    sha256 = "c2ab8a42a0d673c1acb596d276055adcc074c1116e427f118415da3e79e52969",
-    strip_prefix = "grpc-1.27.3",
+    sha256 = "4cbce7f708917b6e58b631c24c59fe720acc8fef5f959df9a58cdf9558d0a79b",
+    strip_prefix = "grpc-1.28.1",
     urls = [
-        "https://github.com/grpc/grpc/archive/v1.27.3.tar.gz",
+        "https://github.com/grpc/grpc/archive/v1.28.1.tar.gz",
     ],
 )
 
diff --git a/crypto/BUILD b/crypto/BUILD
index dbf00cb..8d120f8 100644
--- a/crypto/BUILD
+++ b/crypto/BUILD
@@ -117,6 +117,43 @@
 )
 
 cc_library(
+    name = "commutative_elgamal",
+    srcs = [
+        "commutative_elgamal.cc",
+    ],
+    hdrs = [
+        "commutative_elgamal.h",
+    ],
+    deps = [
+        ":bn_util",
+        ":ec_util",
+        ":elgamal",
+        "//util:status",
+        "//util:status_includes",
+        "@com_github_gflags_gflags//:gflags",
+        "@com_github_glog_glog//:glog",
+    ],
+)
+
+cc_library(
+    name = "ec_point_util",
+    srcs = [
+        "ec_point_util.cc",
+    ],
+    hdrs = [
+        "ec_point_util.h",
+    ],
+    deps = [
+        ":bn_util",
+        ":ec_util",
+        "//util:status",
+        "//util:status_includes",
+        "@com_github_gflags_gflags//:gflags",
+        "@com_github_glog_glog//:glog",
+    ],
+)
+
+cc_library(
     name = "ec_commutative_cipher",
     srcs = [
         "ec_commutative_cipher.cc",