Enable TLS 1.3 by default.

Update-Note: If calling code does not work with TLS 1.3, the simplest
fix is to call SSL_CTX_set_max_proto_version(ctx, TLS1_2_VERSION).

Change-Id: Ic99861753dac117c52aea1988a6c4227a32984ca
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/38624
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>

ssl/ssl_test.cc

diff --git a/ssl/ssl_test.cc b/ssl/ssl_test.cc
index c01443e..8fbf698 100644
--- a/ssl/ssl_test.cc
+++ b/ssl/ssl_test.cc
@@ -888,8 +888,7 @@
 }
 
 TEST(SSLTest, DefaultVersion) {
-  // TODO(svaldez): Update this when TLS 1.3 is enabled by default.
-  ExpectDefaultVersion(TLS1_VERSION, TLS1_2_VERSION, &TLS_method);
+  ExpectDefaultVersion(TLS1_VERSION, TLS1_3_VERSION, &TLS_method);
   ExpectDefaultVersion(TLS1_VERSION, TLS1_VERSION, &TLSv1_method);
   ExpectDefaultVersion(TLS1_1_VERSION, TLS1_1_VERSION, &TLSv1_1_method);
   ExpectDefaultVersion(TLS1_2_VERSION, TLS1_2_VERSION, &TLSv1_2_method);
@@ -2690,7 +2689,7 @@
 
   // Zero is the default version.
   EXPECT_TRUE(SSL_CTX_set_max_proto_version(ctx.get(), 0));
-  EXPECT_EQ(TLS1_2_VERSION, SSL_CTX_get_max_proto_version(ctx.get()));
+  EXPECT_EQ(TLS1_3_VERSION, SSL_CTX_get_max_proto_version(ctx.get()));
   EXPECT_TRUE(SSL_CTX_set_min_proto_version(ctx.get(), 0));
   EXPECT_EQ(TLS1_VERSION, SSL_CTX_get_min_proto_version(ctx.get()));
 
@@ -3775,8 +3774,8 @@
 }
 
 TEST(SSLTest, SealRecord) {
-  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLS_method())),
-      server_ctx(SSL_CTX_new(TLS_method()));
+  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLSv1_2_method())),
+      server_ctx(SSL_CTX_new(TLSv1_2_method()));
   ASSERT_TRUE(client_ctx);
   ASSERT_TRUE(server_ctx);
 
@@ -3818,8 +3817,8 @@
 }
 
 TEST(SSLTest, SealRecordInPlace) {
-  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLS_method())),
-      server_ctx(SSL_CTX_new(TLS_method()));
+  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLSv1_2_method())),
+      server_ctx(SSL_CTX_new(TLSv1_2_method()));
   ASSERT_TRUE(client_ctx);
   ASSERT_TRUE(server_ctx);
 
@@ -3856,8 +3855,8 @@
 }
 
 TEST(SSLTest, SealRecordTrailingData) {
-  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLS_method())),
-      server_ctx(SSL_CTX_new(TLS_method()));
+  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLSv1_2_method())),
+      server_ctx(SSL_CTX_new(TLSv1_2_method()));
   ASSERT_TRUE(client_ctx);
   ASSERT_TRUE(server_ctx);
 
@@ -3895,8 +3894,8 @@
 }
 
 TEST(SSLTest, SealRecordInvalidSpanSize) {
-  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLS_method())),
-      server_ctx(SSL_CTX_new(TLS_method()));
+  bssl::UniquePtr<SSL_CTX> client_ctx(SSL_CTX_new(TLSv1_2_method())),
+      server_ctx(SSL_CTX_new(TLSv1_2_method()));
   ASSERT_TRUE(client_ctx);
   ASSERT_TRUE(server_ctx);
 

ssl/ssl_versions.cc

diff --git a/ssl/ssl_versions.cc b/ssl/ssl_versions.cc
index e63a189..d95aeb3 100644
--- a/ssl/ssl_versions.cc
+++ b/ssl/ssl_versions.cc
@@ -150,7 +150,7 @@
                             uint16_t version) {
   // Zero is interpreted as the default maximum version.
   if (version == 0) {
-    *out = method->is_dtls ? DTLS1_2_VERSION : TLS1_2_VERSION;
+    *out = method->is_dtls ? DTLS1_2_VERSION : TLS1_3_VERSION;
     return true;
   }
 

ssl/test/fuzzer.h

diff --git a/ssl/test/fuzzer.h b/ssl/test/fuzzer.h
index f714d5d..f10c4a0 100644
--- a/ssl/test/fuzzer.h
+++ b/ssl/test/fuzzer.h
@@ -409,10 +409,6 @@
     if (!SSL_CTX_set_strict_cipher_list(ctx_.get(), "ALL:NULL-SHA")) {
       return false;
     }
-    if (protocol_ == kTLS &&
-        !SSL_CTX_set_max_proto_version(ctx_.get(), TLS1_3_VERSION)) {
-      return false;
-    }
 
     static const int kCurves[] = {NID_CECPQ2, NID_X25519, NID_X9_62_prime256v1,
                                   NID_secp384r1, NID_secp521r1};

ssl/test/test_config.cc

diff --git a/ssl/test/test_config.cc b/ssl/test/test_config.cc
index a4a37e6..585e3fd 100644
--- a/ssl/test/test_config.cc
+++ b/ssl/test/test_config.cc
@@ -1143,12 +1143,6 @@
   CRYPTO_once(&once, init_once);
   SSL_CTX_set0_buffer_pool(ssl_ctx.get(), g_pool);
 
-  // Enable TLS 1.3 for tests.
-  if (!is_dtls &&
-      !SSL_CTX_set_max_proto_version(ssl_ctx.get(), TLS1_3_VERSION)) {
-    return nullptr;
-  }
-
   std::string cipher_list = "ALL";
   if (!cipher.empty()) {
     cipher_list = cipher;