Check the server did not use a TLS 1.2 cipher suite pre-TLS 1.2.

This check got refactored in OpenSSL 1.0.2 and broke in the process. Fix this
and add a test. Otherwise things like client auth can get slightly confused; it
will try to sign the MD5/SHA-1 hash, but the TLS 1.2 cipher suite may not use
SSL_HANDSHAKE_MAC_DEFAULT, so those digests won't be available.

Based on upstream's 226751ae4a1f3e00021c43399d7bb51a99c22c17.

Change-Id: I5b864d3a696f3187b849c53b872c24fb7df27924
Reviewed-on: https://boringssl-review.googlesource.com/1696
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/test/runner/common.go b/ssl/test/runner/common.go
index fa0e6d8..f22f95a 100644
--- a/ssl/test/runner/common.go
+++ b/ssl/test/runner/common.go
@@ -445,6 +445,10 @@
 	// ClientKeyExchange message without the two-byte length
 	// prefix, as if it were SSL3.
 	SSL3RSAKeyExchange bool
+
+	// SkipCipherVersionCheck causes the server to negotiate
+	// TLS 1.2 ciphers in earlier versions of TLS.
+	SkipCipherVersionCheck bool
 }
 
 func (c *Config) serverInit() {
diff --git a/ssl/test/runner/handshake_server.go b/ssl/test/runner/handshake_server.go
index 855f992..6d61fd5 100644
--- a/ssl/test/runner/handshake_server.go
+++ b/ssl/test/runner/handshake_server.go
@@ -832,7 +832,7 @@
 			if (candidate.flags&suiteECDSA != 0) != ecdsaOk {
 				continue
 			}
-			if version < VersionTLS12 && candidate.flags&suiteTLS12 != 0 {
+			if !c.config.Bugs.SkipCipherVersionCheck && version < VersionTLS12 && candidate.flags&suiteTLS12 != 0 {
 				continue
 			}
 			if c.isDTLS && candidate.flags&suiteNoDTLS != 0 {
diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index d238e8a..9322592 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -483,6 +483,18 @@
 		shouldFail:    true,
 		expectedError: ":HTTPS_PROXY_REQUEST:",
 	},
+	{
+		name: "SkipCipherVersionCheck",
+		config: Config{
+			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_GCM_SHA256},
+			MaxVersion:   VersionTLS11,
+			Bugs: ProtocolBugs{
+				SkipCipherVersionCheck: true,
+			},
+		},
+		shouldFail:    true,
+		expectedError: ":WRONG_CIPHER_RETURNED:",
+	},
 }
 
 func doExchange(test *testCase, config *Config, conn net.Conn, messageLen int) error {