diff --git a/crypto/poly1305/CMakeLists.txt b/crypto/poly1305/CMakeLists.txt
index bb0c1e4..31ad9d5 100644
--- a/crypto/poly1305/CMakeLists.txt
+++ b/crypto/poly1305/CMakeLists.txt
@@ -19,3 +19,12 @@
 
   ${POLY1305_ARCH_SOURCES}
 )
+
+add_executable(
+  poly1305_test
+
+  poly1305_test.cc
+  $<TARGET_OBJECTS:test_support>
+)
+
+target_link_libraries(poly1305_test crypto)
diff --git a/crypto/poly1305/poly1305_test.cc b/crypto/poly1305/poly1305_test.cc
new file mode 100644
index 0000000..fd1c89a
--- /dev/null
+++ b/crypto/poly1305/poly1305_test.cc
@@ -0,0 +1,74 @@
+/* Copyright (c) 2015, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <stdio.h>
+#include <string.h>
+
+#include <vector>
+
+#include <openssl/crypto.h>
+#include <openssl/poly1305.h>
+
+#include "../test/file_test.h"
+#include "../test/stl_compat.h"
+
+
+static bool TestPoly1305(FileTest *t, void *arg) {
+  std::vector<uint8_t> key, in, mac;
+  if (!t->GetBytes(&key, "Key") ||
+      !t->GetBytes(&in, "Input") ||
+      !t->GetBytes(&mac, "MAC")) {
+    return false;
+  }
+  if (key.size() != 32 || mac.size() != 16) {
+    t->PrintLine("Invalid test");
+    return false;
+  }
+
+  // Test single-shot operation.
+  poly1305_state state;
+  CRYPTO_poly1305_init(&state, bssl::vector_data(&key));
+  CRYPTO_poly1305_update(&state, bssl::vector_data(&in), in.size());
+  // |CRYPTO_poly1305_finish| requires a 16-byte-aligned output.
+  alignas(16) uint8_t out[16];
+  CRYPTO_poly1305_finish(&state, out);
+  if (!t->ExpectBytesEqual(out, 16, bssl::vector_data(&mac), mac.size())) {
+    t->PrintLine("Single-shot Poly1305 failed.");
+    return false;
+  }
+
+  // Test streaming byte-by-byte.
+  CRYPTO_poly1305_init(&state, bssl::vector_data(&key));
+  for (size_t i = 0; i < in.size(); i++) {
+    CRYPTO_poly1305_update(&state, &in[i], 1);
+  }
+  CRYPTO_poly1305_finish(&state, out);
+  if (!t->ExpectBytesEqual(out, 16, bssl::vector_data(&mac), mac.size())) {
+    t->PrintLine("Streaming Poly1305 failed.");
+    return false;
+  }
+
+  return true;
+}
+
+int main(int argc, char **argv) {
+  CRYPTO_library_init();
+
+  if (argc != 2) {
+    fprintf(stderr, "%s <test file>\n", argv[0]);
+    return 1;
+  }
+
+  return FileTestMain(TestPoly1305, nullptr, argv[1]);
+}
diff --git a/crypto/poly1305/poly1305_test.txt b/crypto/poly1305/poly1305_test.txt
new file mode 100644
index 0000000..6c5d403
--- /dev/null
+++ b/crypto/poly1305/poly1305_test.txt
@@ -0,0 +1,52 @@
+# RFC 7359, section 2.5.2.
+
+Key = 85d6be7857556d337f4452fe42d506a80103808afb0db2fd4abff6af4149f51b
+Input = "Cryptographic Forum Research Group"
+MAC = a8061dc1305136c6c22b8baf0c0127a9
+
+
+# RFC 7359, section A.3.
+
+Key = 0000000000000000000000000000000000000000000000000000000000000000
+Input = 00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+MAC = 00000000000000000000000000000000
+
+Key = 0000000000000000000000000000000036e5f6b5c5e06070f0efca96227a863e
+Input = 416e79207375626d697373696f6e20746f20746865204945544620696e74656e6465642062792074686520436f6e7472696275746f7220666f72207075626c69636174696f6e20617320616c6c206f722070617274206f6620616e204945544620496e7465726e65742d4472616674206f722052464320616e6420616e792073746174656d656e74206d6164652077697468696e2074686520636f6e74657874206f6620616e204945544620616374697669747920697320636f6e7369646572656420616e20224945544620436f6e747269627574696f6e222e20537563682073746174656d656e747320696e636c756465206f72616c2073746174656d656e747320696e20494554462073657373696f6e732c2061732077656c6c206173207772697474656e20616e6420656c656374726f6e696320636f6d6d756e69636174696f6e73206d61646520617420616e792074696d65206f7220706c6163652c207768696368206172652061646472657373656420746f
+MAC = 36e5f6b5c5e06070f0efca96227a863e
+
+Key = 36e5f6b5c5e06070f0efca96227a863e00000000000000000000000000000000
+Input = 416e79207375626d697373696f6e20746f20746865204945544620696e74656e6465642062792074686520436f6e7472696275746f7220666f72207075626c69636174696f6e20617320616c6c206f722070617274206f6620616e204945544620496e7465726e65742d4472616674206f722052464320616e6420616e792073746174656d656e74206d6164652077697468696e2074686520636f6e74657874206f6620616e204945544620616374697669747920697320636f6e7369646572656420616e20224945544620436f6e747269627574696f6e222e20537563682073746174656d656e747320696e636c756465206f72616c2073746174656d656e747320696e20494554462073657373696f6e732c2061732077656c6c206173207772697474656e20616e6420656c656374726f6e696320636f6d6d756e69636174696f6e73206d61646520617420616e792074696d65206f7220706c6163652c207768696368206172652061646472657373656420746f
+MAC = f3477e7cd95417af89a6b8794c310cf0
+
+Key = 1c9240a5eb55d38af333888604f6b5f0473917c1402b80099dca5cbc207075c0
+Input = 2754776173206272696c6c69672c20616e642074686520736c6974687920746f7665730a446964206779726520616e642067696d626c6520696e2074686520776162653a0a416c6c206d696d737920776572652074686520626f726f676f7665732c0a416e6420746865206d6f6d65207261746873206f757467726162652e
+MAC = 4541669a7eaaee61e708dc7cbcc5eb62
+
+Key = 0200000000000000000000000000000000000000000000000000000000000000
+Input = ffffffffffffffffffffffffffffffff
+MAC = 03000000000000000000000000000000
+
+Key = 02000000000000000000000000000000ffffffffffffffffffffffffffffffff
+Input = 02000000000000000000000000000000
+MAC = 03000000000000000000000000000000
+
+Key = 0100000000000000000000000000000000000000000000000000000000000000
+Input = fffffffffffffffffffffffffffffffff0ffffffffffffffffffffffffffffff11000000000000000000000000000000
+MAC = 05000000000000000000000000000000
+
+Key = 0100000000000000000000000000000000000000000000000000000000000000
+Input = fffffffffffffffffffffffffffffffffbfefefefefefefefefefefefefefefe01010101010101010101010101010101
+MAC = 00000000000000000000000000000000
+
+Key = 0200000000000000000000000000000000000000000000000000000000000000
+Input = fdffffffffffffffffffffffffffffff
+MAC = faffffffffffffffffffffffffffffff
+
+Key = 0100000000000000040000000000000000000000000000000000000000000000
+Input = e33594d7505e43b900000000000000003394d7505e4379cd01000000000000000000000000000000000000000000000001000000000000000000000000000000
+MAC = 14000000000000005500000000000000
+
+Key = 0100000000000000040000000000000000000000000000000000000000000000
+Input = e33594d7505e43b900000000000000003394d7505e4379cd010000000000000000000000000000000000000000000000
+MAC = 13000000000000000000000000000000
diff --git a/include/openssl/poly1305.h b/include/openssl/poly1305.h
index aa90486..32e109e 100644
--- a/include/openssl/poly1305.h
+++ b/include/openssl/poly1305.h
@@ -22,7 +22,7 @@
 #endif
 
 
-typedef unsigned char poly1305_state[512];
+typedef uint8_t poly1305_state[512];
 
 /* poly1305_init sets up |state| so that it can be used to calculate an
  * authentication tag with the one-time key |key|. Note that |key| is a
diff --git a/util/all_tests.json b/util/all_tests.json
index eb40ed9..77ffa0a 100644
--- a/util/all_tests.json
+++ b/util/all_tests.json
@@ -45,6 +45,7 @@
 	["crypto/lhash/lhash_test"],
 	["crypto/modes/gcm_test"],
 	["crypto/pkcs8/pkcs12_test"],
+	["crypto/poly1305/poly1305_test", "crypto/poly1305/poly1305_test.txt"],
 	["crypto/refcount_test"],
 	["crypto/rsa/rsa_test"],
 	["crypto/thread_test"],