Change DTLS default from 1.0 to 1.2 for webrtc.

webrtc/base/opensslstreamadapter.cc

Index: webrtc/base/opensslstreamadapter.cc
diff --git a/webrtc/base/opensslstreamadapter.cc b/webrtc/base/opensslstreamadapter.cc
index 270faa0809f42013c01aeb35854d7c98b3b9cc1f..b6792523d9fd99fcf9ee96ee6315769890ad36dd 100644
--- a/webrtc/base/opensslstreamadapter.cc
+++ b/webrtc/base/opensslstreamadapter.cc
@@ -25,6 +25,7 @@
 
 #include <vector>
 
+#include "webrtc/base/checks.h"
 #include "webrtc/base/common.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/safe_conversions.h"
@@ -162,10 +163,14 @@ static int kDefaultSslEcCipher12 =
 // Fallback cipher for DTLS 1.2 if hardware-accelerated AES-GCM is unavailable.
 // TODO(davidben): Switch to the standardized CHACHA20_POLY1305 variant when
 // available.
-static int kDefaultSslCipher12NoAesGcm =
+static int kDefaultSslCipher12NoAesGcmNonStandard =
     static_cast<uint16_t>(TLS1_CK_ECDHE_RSA_CHACHA20_POLY1305_OLD);
-static int kDefaultSslEcCipher12NoAesGcm =
+static int kDefaultSslEcCipher12NoAesGcmNonStandard =
     static_cast<uint16_t>(TLS1_CK_ECDHE_ECDSA_CHACHA20_POLY1305_OLD);
+static int kDefaultSslCipher12NoAesGcm =
+    static_cast<uint16_t>(TLS1_CK_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256);
+static int kDefaultSslEcCipher12NoAesGcm =
+    static_cast<uint16_t>(TLS1_CK_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256);
 #else  // !OPENSSL_IS_BORINGSSL
 // OpenSSL sorts differently than BoringSSL, so the default cipher doesn't
 // change between TLS 1.0 and TLS 1.2 with the current setup.
@@ -301,12 +306,13 @@ OpenSSLStreamAdapter::OpenSSLStreamAdapter(StreamInterface* stream)
     : SSLStreamAdapter(stream),
       state_(SSL_NONE),
       role_(SSL_CLIENT),
-      ssl_read_needs_write_(false), ssl_write_needs_read_(false),
-      ssl_(NULL), ssl_ctx_(NULL),
+      ssl_read_needs_write_(false),
+      ssl_write_needs_read_(false),
+      ssl_(NULL),
+      ssl_ctx_(NULL),
       custom_verification_succeeded_(false),
       ssl_mode_(SSL_MODE_TLS),
-      ssl_max_version_(SSL_PROTOCOL_TLS_11) {
-}
+      ssl_max_version_(SSL_PROTOCOL_TLS_12) {}
 
 OpenSSLStreamAdapter::~OpenSSLStreamAdapter() {
   Cleanup();
@@ -1138,7 +1144,12 @@ int OpenSSLStreamAdapter::GetDefaultSslCipherForTest(SSLProtocolVersion version,
         if (EVP_has_aes_hardware()) {
           return kDefaultSslCipher12;
         } else {
-          return kDefaultSslCipher12NoAesGcm;
+          if (EVP_aead_chacha20_poly1305()) {
+            return kDefaultSslCipher12NoAesGcm;
+          } else {
+            RTC_CHECK(EVP_aead_chacha20_poly1305_old());
+            return kDefaultSslCipher12NoAesGcmNonStandard;
+          }

[davidben_webrtc, 2016/01/11 21:10:55]

Eh? Both of these functions will only ever return non-null or be a compile
error. That's not how this works. They morally should be constants but OpenSSL
historically had some problems exporting constants out of shared libraries on
some platforms.

As I said on https://codereview.webrtc.org/1550773002/, you should get rid of
these tests as they're really not helpful. They only serve to make things harder
for everyone when I make BoringSSL changes.

         }
 #else  // !OPENSSL_IS_BORINGSSL
         return kDefaultSslCipher12;
@@ -1155,7 +1166,12 @@ int OpenSSLStreamAdapter::GetDefaultSslCipherForTest(SSLProtocolVersion version,
         if (EVP_has_aes_hardware()) {
           return kDefaultSslEcCipher12;
         } else {
-          return kDefaultSslEcCipher12NoAesGcm;
+          if (EVP_aead_chacha20_poly1305()) {
+            return kDefaultSslEcCipher12NoAesGcm;
+          } else {
+            RTC_CHECK(EVP_aead_chacha20_poly1305_old());
+            return kDefaultSslEcCipher12NoAesGcmNonStandard;
+          }
         }
 #else  // !OPENSSL_IS_BORINGSSL
         return kDefaultSslEcCipher12;