Fix the OpenSSL implementation of ExportKeyingMaterial.

net/socket/ssl_client_socket_unittest.cc

Index: net/socket/ssl_client_socket_unittest.cc
diff --git a/net/socket/ssl_client_socket_unittest.cc b/net/socket/ssl_client_socket_unittest.cc
index 3a4ff5bfc0deac9c2d85d9593b5cbf64935b354c..82da59497dbfcebdc43e0546b705f342290feb6f 100644
--- a/net/socket/ssl_client_socket_unittest.cc
+++ b/net/socket/ssl_client_socket_unittest.cc
@@ -2337,18 +2337,32 @@ TEST_F(SSLClientSocketTest, ExportKeyingMaterial) {
 
   const int kKeyingMaterialSize = 32;
   const char kKeyingLabel1[] = "client-socket-test-1";
-  const char kKeyingContext[] = "";
+  const char kKeyingContext1[] = "";
   unsigned char client_out1[kKeyingMaterialSize];
   memset(client_out1, 0, sizeof(client_out1));
-  rv = sock->ExportKeyingMaterial(
-      kKeyingLabel1, false, kKeyingContext, client_out1, sizeof(client_out1));
+  rv = sock->ExportKeyingMaterial(kKeyingLabel1, false, kKeyingContext1,
+                                  client_out1, sizeof(client_out1));
   EXPECT_EQ(rv, OK);
 
   const char kKeyingLabel2[] = "client-socket-test-2";
   unsigned char client_out2[kKeyingMaterialSize];
   memset(client_out2, 0, sizeof(client_out2));
-  rv = sock->ExportKeyingMaterial(
-      kKeyingLabel2, false, kKeyingContext, client_out2, sizeof(client_out2));
+  rv = sock->ExportKeyingMaterial(kKeyingLabel2, false, kKeyingContext1,
+                                  client_out2, sizeof(client_out2));
+  EXPECT_EQ(rv, OK);
+  EXPECT_NE(memcmp(client_out1, client_out2, kKeyingMaterialSize), 0);
+
+  const char kKeyingContext2[] = "context";
+  rv = sock->ExportKeyingMaterial(kKeyingLabel1, true, kKeyingContext2,
+                                  client_out2, sizeof(client_out2));
+  EXPECT_EQ(rv, OK);
+  EXPECT_NE(memcmp(client_out1, client_out2, kKeyingMaterialSize), 0);
+
+  // Using an empty context should give different key material from not using a
+  // context at all.
+  memset(client_out2, 0, sizeof(client_out2));
+  rv = sock->ExportKeyingMaterial(kKeyingLabel1, true, kKeyingContext1,
+                                  client_out2, sizeof(client_out2));
   EXPECT_EQ(rv, OK);
   EXPECT_NE(memcmp(client_out1, client_out2, kKeyingMaterialSize), 0);
 }