Component updater must fallback on using HTTP on Windows XPSP2 and below

base/win/win_util.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/win/win_util.h"
 
 #include <aclapi.h>
 #include <lm.h>
 #include <powrprof.h>
 #include <shellapi.h>
@@ skipping 352 matching lines @@
                                  UNKNOWN);
   }
 
   return g_domain_state == ENROLLED;
 }
 
 void SetDomainStateForTesting(bool state) {
   g_domain_state = state ? ENROLLED : NOT_ENROLLED;
 }
 
+bool MaybeHasSHA256Support() {
+  const base::win::OSInfo* os_info = base::win::OSInfo::GetInstance();
+
+  if (os_info->version() == base::win::VERSION_PRE_XP)
+    return false;  // Too old to have it and this OS is not supported anyway.
+
+  if (os_info->version() == base::win::VERSION_XP)
+    return os_info->service_pack().major >= 3;  // Windows XP SP3 has it.
+
+  // Assume it is missing in this case, although it may not be. This category
+  // includes Windows XP x64, and Windows Server, where a hotfix could be
+  // deployed.
+  if (os_info->version() == base::win::VERSION_SERVER_2003)
+    return false;
+
+  DCHECK(os_info->version() >= base::win::VERSION_VISTA);
+  return true;  // New enough to have SHA-256 support.
+}
+
 }  // namespace win
 }  // namespace base
 
 #ifdef _MSC_VER
 
 // There are optimizer bugs in x86 VS2012 pre-Update 1.
 #if _MSC_VER == 1700 && defined _M_IX86 && _MSC_FULL_VER < 170051106
 
 #pragma message("Relevant defines:")
 #define __STR2__(x) #x
 #define __STR1__(x) __STR2__(x)
 #define __PPOUT__(x) "#define " #x " " __STR1__(x)
 #if defined(_M_IX86)
   #pragma message(__PPOUT__(_M_IX86))
 #endif
 #if defined(_M_X64)
   #pragma message(__PPOUT__(_M_X64))
 #endif
 #if defined(_MSC_FULL_VER)
   #pragma message(__PPOUT__(_MSC_FULL_VER))
 #endif
 
 #pragma message("Visual Studio 2012 x86 must be updated to at least Update 1")
 #error Must install Update 1 to Visual Studio 2012.
 #endif
 
 #endif  // _MSC_VER