diff --git a/tool/CMakeLists.txt b/tool/CMakeLists.txt
index 81201c7e..03f52029 100644
--- a/tool/CMakeLists.txt
+++ b/tool/CMakeLists.txt
@@ -3,8 +3,9 @@ include_directories(../include)
 add_executable(
 	bssl
 
-	tool.cc
 	const.cc
+	speed.cc
+	tool.cc
 )
 
 target_link_libraries(bssl ssl crypto -lrt)
diff --git a/tool/speed.cc b/tool/speed.cc
new file mode 100644
index 00000000..706d4a27
--- /dev/null
+++ b/tool/speed.cc
@@ -0,0 +1,239 @@
+/* Copyright (c) 2014, 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 <string>
+#include <functional>
+#include <memory>
+#include <vector>
+
+#include <stdint.h>
+#include <time.h>
+
+#include <openssl/aead.h>
+#include <openssl/bio.h>
+#include <openssl/obj.h>
+#include <openssl/rsa.h>
+
+#if defined(OPENSSL_WINDOWS)
+#include <Windows.h>
+#endif
+
+extern "C" {
+// These values are DER encoded, RSA private keys.
+extern const uint8_t kDERRSAPrivate2048[];
+extern size_t kDERRSAPrivate2048Len;
+extern const uint8_t kDERRSAPrivate4096[];
+extern size_t kDERRSAPrivate4096Len;
+}
+
+// TimeResults represents the results of benchmarking a function.
+struct TimeResults {
+  // num_calls is the number of function calls done in the time period.
+  unsigned num_calls;
+  // us is the number of microseconds that elapsed in the time period.
+  unsigned us;
+
+  void Print(const std::string &description) {
+    printf("Did %u %s operations in %uus (%.1f ops/sec)\n", num_calls,
+           description.c_str(), us,
+           (static_cast<double>(num_calls) / us) * 1000000);
+  }
+
+  void PrintWithBytes(const std::string &description, size_t bytes_per_call) {
+    printf("Did %u %s operations in %uus (%.1f ops/sec): %.1f MB/s\n",
+           num_calls, description.c_str(), us,
+           (static_cast<double>(num_calls) / us) * 1000000,
+           static_cast<double>(bytes_per_call * num_calls) / us);
+  }
+};
+
+#if defined(OPENSSL_WINDOWS)
+static uint64_t time_now() { return GetTickCount64() * 1000; }
+#else
+static uint64_t time_now() {
+  struct timespec ts;
+  clock_gettime(CLOCK_MONOTONIC, &ts);
+
+  uint64_t ret = ts.tv_sec;
+  ret *= 1000000;
+  ret += ts.tv_nsec / 1000;
+  return ret;
+}
+#endif
+
+static bool TimeFunction(TimeResults *results, std::function<bool()> func) {
+  // kTotalMS is the total amount of time that we'll aim to measure a function
+  // for.
+  static const uint64_t kTotalUS = 3000000;
+  uint64_t start = time_now(), now, delta;
+  unsigned done = 0, iterations_between_time_checks;
+
+  if (!func()) {
+    return false;
+  }
+  now = time_now();
+  delta = now - start;
+  if (delta == 0) {
+    iterations_between_time_checks = 250;
+  } else {
+    // Aim for about 100ms between time checks.
+    iterations_between_time_checks =
+        static_cast<double>(100000) / static_cast<double>(delta);
+    if (iterations_between_time_checks > 1000) {
+      iterations_between_time_checks = 1000;
+    } else if (iterations_between_time_checks < 1) {
+      iterations_between_time_checks = 1;
+    }
+  }
+
+  for (;;) {
+    for (unsigned i = 0; i < iterations_between_time_checks; i++) {
+      if (!func()) {
+        return false;
+      }
+      done++;
+    }
+
+    now = time_now();
+    if (now - start > kTotalUS) {
+      break;
+    }
+  }
+
+  results->us = now - start;
+  results->num_calls = done;
+  return true;
+}
+
+static bool SpeedRSA(const std::string& key_name, RSA *key) {
+  TimeResults results;
+
+  std::unique_ptr<uint8_t[]> sig(new uint8_t[RSA_size(key)]);
+  const uint8_t fake_sha256_hash[32] = {0};
+  unsigned sig_len;
+
+  if (!TimeFunction(&results,
+                    [key, &sig, &fake_sha256_hash, &sig_len]() -> bool {
+        return RSA_sign(NID_sha256, fake_sha256_hash, sizeof(fake_sha256_hash),
+                        sig.get(), &sig_len, key);
+      })) {
+    fprintf(stderr, "RSA_sign failed.\n");
+    BIO_print_errors_fp(stderr);
+    return false;
+  }
+  results.Print(key_name + " signing");
+
+  if (!TimeFunction(&results,
+                    [key, &fake_sha256_hash, &sig, sig_len]() -> bool {
+        return RSA_verify(NID_sha256, fake_sha256_hash,
+                          sizeof(fake_sha256_hash), sig.get(), sig_len, key);
+      })) {
+    fprintf(stderr, "RSA_verify failed.\n");
+    BIO_print_errors_fp(stderr);
+    return false;
+  }
+  results.Print(key_name + " verify");
+
+  return true;
+}
+
+static bool SpeedAEADChunk(const EVP_AEAD *aead, const std::string &name,
+                           size_t chunk_len) {
+  EVP_AEAD_CTX ctx;
+  const size_t key_len = EVP_AEAD_key_length(aead);
+  const size_t nonce_len = EVP_AEAD_nonce_length(aead);
+  const size_t overhead_len = EVP_AEAD_max_overhead(aead);
+
+  std::unique_ptr<uint8_t[]> key(new uint8_t[key_len]);
+  memset(key.get(), 0, key_len);
+  std::unique_ptr<uint8_t[]> nonce(new uint8_t[nonce_len]);
+  memset(nonce.get(), 0, nonce_len);
+  std::unique_ptr<uint8_t[]> in(new uint8_t[chunk_len]);
+  memset(in.get(), 0, chunk_len);
+  std::unique_ptr<uint8_t[]> out(new uint8_t[chunk_len + overhead_len]);
+  memset(out.get(), 0, chunk_len + overhead_len);
+
+  if (!EVP_AEAD_CTX_init(&ctx, aead, key.get(), key_len,
+                         EVP_AEAD_DEFAULT_TAG_LENGTH, NULL)) {
+    fprintf(stderr, "Failed to create EVP_AEAD_CTX.\n");
+    BIO_print_errors_fp(stderr);
+    return false;
+  }
+
+  TimeResults results;
+  if (!TimeFunction(&results, [chunk_len, overhead_len, nonce_len, &in, &out,
+                               &ctx, &nonce]() -> bool {
+        size_t out_len;
+
+        return EVP_AEAD_CTX_seal(&ctx, out.get(), &out_len,
+                                 chunk_len + overhead_len, nonce.get(),
+                                 nonce_len, in.get(), chunk_len, NULL, 0);
+      })) {
+    fprintf(stderr, "EVP_AEAD_CTX_seal failed.\n");
+    BIO_print_errors_fp(stderr);
+    return false;
+  }
+
+  results.PrintWithBytes(name + " seal", chunk_len);
+
+  EVP_AEAD_CTX_cleanup(&ctx);
+
+  return true;
+}
+
+static bool SpeedAEAD(const EVP_AEAD *aead, const std::string &name) {
+  return SpeedAEADChunk(aead, name + " (16 bytes)", 16) &&
+         SpeedAEADChunk(aead, name + " (1350 bytes)", 1350) &&
+         SpeedAEADChunk(aead, name + " (8192 bytes)", 8192);
+}
+
+bool Speed(const std::vector<std::string> &args) {
+  const uint8_t *inp;
+
+  RSA *key = NULL;
+  inp = kDERRSAPrivate2048;
+  if (NULL == d2i_RSAPrivateKey(&key, &inp, kDERRSAPrivate2048Len)) {
+    fprintf(stderr, "Failed to parse RSA key.\n");
+    BIO_print_errors_fp(stderr);
+    return false;
+  }
+
+  if (!SpeedRSA("RSA 2048", key)) {
+    return false;
+  }
+
+  RSA_free(key);
+  key = NULL;
+
+  inp = kDERRSAPrivate4096;
+  if (NULL == d2i_RSAPrivateKey(&key, &inp, kDERRSAPrivate4096Len)) {
+    fprintf(stderr, "Failed to parse 4096-bit RSA key.\n");
+    BIO_print_errors_fp(stderr);
+    return 1;
+  }
+
+  if (!SpeedRSA("RSA 4096", key)) {
+    return false;
+  }
+
+  RSA_free(key);
+
+  if (!SpeedAEAD(EVP_aead_aes_128_gcm(), "AES-128-GCM") ||
+      !SpeedAEAD(EVP_aead_aes_256_gcm(), "AES-256-GCM") ||
+      !SpeedAEAD(EVP_aead_chacha20_poly1305(), "ChaCha20-Poly1305")) {
+    return false;
+  }
+
+  return 0;
+}
diff --git a/tool/tool.cc b/tool/tool.cc
index 88d7cf72..4bcfdb3e 100644
--- a/tool/tool.cc
+++ b/tool/tool.cc
@@ -13,233 +13,14 @@
  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
 
 #include <string>
-#include <functional>
-#include <memory>
 #include <vector>
 
-#include <stdint.h>
-#include <time.h>
-
-#include <openssl/aead.h>
-#include <openssl/bio.h>
 #include <openssl/err.h>
-#include <openssl/obj.h>
-#include <openssl/rsa.h>
-
-#if defined(OPENSSL_WINDOWS)
-#include <Windows.h>
-#endif
-
-extern "C" {
-// These values are DER encoded, RSA private keys.
-extern const uint8_t kDERRSAPrivate2048[];
-extern size_t kDERRSAPrivate2048Len;
-extern const uint8_t kDERRSAPrivate4096[];
-extern size_t kDERRSAPrivate4096Len;
-}
 
-// TimeResults represents the results of benchmarking a function.
-struct TimeResults {
-  // num_calls is the number of function calls done in the time period.
-  unsigned num_calls;
-  // us is the number of microseconds that elapsed in the time period.
-  unsigned us;
-
-  void Print(const std::string &description) {
-    printf("Did %u %s operations in %uus (%.1f ops/sec)\n", num_calls,
-           description.c_str(), us,
-           (static_cast<double>(num_calls) / us) * 1000000);
-  }
-
-  void PrintWithBytes(const std::string &description, size_t bytes_per_call) {
-    printf("Did %u %s operations in %uus (%.1f ops/sec): %.1f MB/s\n",
-           num_calls, description.c_str(), us,
-           (static_cast<double>(num_calls) / us) * 1000000,
-           static_cast<double>(bytes_per_call * num_calls) / us);
-  }
-};
-
-#if defined(OPENSSL_WINDOWS)
-static uint64_t time_now() { return GetTickCount64() * 1000; }
-#else
-static uint64_t time_now() {
-  struct timespec ts;
-  clock_gettime(CLOCK_MONOTONIC, &ts);
-
-  uint64_t ret = ts.tv_sec;
-  ret *= 1000000;
-  ret += ts.tv_nsec / 1000;
-  return ret;
-}
-#endif
-
-static bool TimeFunction(TimeResults *results, std::function<bool()> func) {
-  // kTotalMS is the total amount of time that we'll aim to measure a function
-  // for.
-  static const uint64_t kTotalUS = 3000000;
-  uint64_t start = time_now(), now, delta;
-  unsigned done = 0, iterations_between_time_checks;
-
-  if (!func()) {
-    return false;
-  }
-  now = time_now();
-  delta = now - start;
-  if (delta == 0) {
-    iterations_between_time_checks = 250;
-  } else {
-    // Aim for about 100ms between time checks.
-    iterations_between_time_checks =
-        static_cast<double>(100000) / static_cast<double>(delta);
-    if (iterations_between_time_checks > 1000) {
-      iterations_between_time_checks = 1000;
-    } else if (iterations_between_time_checks < 1) {
-      iterations_between_time_checks = 1;
-    }
-  }
-
-  for (;;) {
-    for (unsigned i = 0; i < iterations_between_time_checks; i++) {
-      if (!func()) {
-        return false;
-      }
-      done++;
-    }
-
-    now = time_now();
-    if (now - start > kTotalUS) {
-      break;
-    }
-  }
-
-  results->us = now - start;
-  results->num_calls = done;
-  return true;
-}
-
-static bool SpeedRSA(const std::string& key_name, RSA *key) {
-  TimeResults results;
-
-  std::unique_ptr<uint8_t[]> sig(new uint8_t[RSA_size(key)]);
-  const uint8_t fake_sha256_hash[32] = {0};
-  unsigned sig_len;
-
-  if (!TimeFunction(&results,
-                    [key, &sig, &fake_sha256_hash, &sig_len]() -> bool {
-        return RSA_sign(NID_sha256, fake_sha256_hash, sizeof(fake_sha256_hash),
-                        sig.get(), &sig_len, key);
-      })) {
-    fprintf(stderr, "RSA_sign failed.\n");
-    BIO_print_errors_fp(stderr);
-    return false;
-  }
-  results.Print(key_name + " signing");
-
-  if (!TimeFunction(&results,
-                    [key, &fake_sha256_hash, &sig, sig_len]() -> bool {
-        return RSA_verify(NID_sha256, fake_sha256_hash,
-                          sizeof(fake_sha256_hash), sig.get(), sig_len, key);
-      })) {
-    fprintf(stderr, "RSA_verify failed.\n");
-    BIO_print_errors_fp(stderr);
-    return false;
-  }
-  results.Print(key_name + " verify");
-
-  return true;
-}
 
-static bool SpeedAEADChunk(const EVP_AEAD *aead, const std::string &name,
-                           size_t chunk_len) {
-  EVP_AEAD_CTX ctx;
-  const size_t key_len = EVP_AEAD_key_length(aead);
-  const size_t nonce_len = EVP_AEAD_nonce_length(aead);
-  const size_t overhead_len = EVP_AEAD_max_overhead(aead);
-
-  std::unique_ptr<uint8_t[]> key(new uint8_t[key_len]);
-  memset(key.get(), 0, key_len);
-  std::unique_ptr<uint8_t[]> nonce(new uint8_t[nonce_len]);
-  memset(nonce.get(), 0, nonce_len);
-  std::unique_ptr<uint8_t[]> in(new uint8_t[chunk_len]);
-  memset(in.get(), 0, chunk_len);
-  std::unique_ptr<uint8_t[]> out(new uint8_t[chunk_len + overhead_len]);
-  memset(out.get(), 0, chunk_len + overhead_len);
-
-  if (!EVP_AEAD_CTX_init(&ctx, aead, key.get(), key_len,
-                         EVP_AEAD_DEFAULT_TAG_LENGTH, NULL)) {
-    fprintf(stderr, "Failed to create EVP_AEAD_CTX.\n");
-    BIO_print_errors_fp(stderr);
-    return false;
-  }
-
-  TimeResults results;
-  if (!TimeFunction(&results, [chunk_len, overhead_len, nonce_len, &in, &out,
-                               &ctx, &nonce]() -> bool {
-        size_t out_len;
-
-        return EVP_AEAD_CTX_seal(&ctx, out.get(), &out_len,
-                                 chunk_len + overhead_len, nonce.get(),
-                                 nonce_len, in.get(), chunk_len, NULL, 0);
-      })) {
-    fprintf(stderr, "EVP_AEAD_CTX_seal failed.\n");
-    BIO_print_errors_fp(stderr);
-    return false;
-  }
-
-  results.PrintWithBytes(name + " seal", chunk_len);
-
-  EVP_AEAD_CTX_cleanup(&ctx);
-
-  return true;
-}
-
-static bool SpeedAEAD(const EVP_AEAD *aead, const std::string &name) {
-  return SpeedAEADChunk(aead, name + " (16 bytes)", 16) &&
-         SpeedAEADChunk(aead, name + " (1350 bytes)", 1350) &&
-         SpeedAEADChunk(aead, name + " (8192 bytes)", 8192);
-}
-
-static bool Speed(const std::vector<std::string> &args) {
-  const uint8_t *inp;
-
-  RSA *key = NULL;
-  inp = kDERRSAPrivate2048;
-  if (NULL == d2i_RSAPrivateKey(&key, &inp, kDERRSAPrivate2048Len)) {
-    fprintf(stderr, "Failed to parse RSA key.\n");
-    BIO_print_errors_fp(stderr);
-    return false;
-  }
-
-  if (!SpeedRSA("RSA 2048", key)) {
-    return false;
-  }
-
-  RSA_free(key);
-  key = NULL;
-
-  inp = kDERRSAPrivate4096;
-  if (NULL == d2i_RSAPrivateKey(&key, &inp, kDERRSAPrivate4096Len)) {
-    fprintf(stderr, "Failed to parse 4096-bit RSA key.\n");
-    BIO_print_errors_fp(stderr);
-    return 1;
-  }
-
-  if (!SpeedRSA("RSA 4096", key)) {
-    return false;
-  }
-
-  RSA_free(key);
-
-  if (!SpeedAEAD(EVP_aead_aes_128_gcm(), "AES-128-GCM") ||
-      !SpeedAEAD(EVP_aead_aes_256_gcm(), "AES-256-GCM") ||
-      !SpeedAEAD(EVP_aead_chacha20_poly1305(), "ChaCha20-Poly1305")) {
-    return false;
-  }
-
-  return 0;
-}
+bool Speed(const std::vector<std::string> &args);
 
-void usage(const char *name) {
+static void usage(const char *name) {
   printf("Usage: %s [speed]\n", name);
 }