Whitelist Widevine CDM for plugin UMA on all platforms.

chrome/renderer/pepper/pepper_uma_host.cc

Index: chrome/renderer/pepper/pepper_uma_host.cc
diff --git a/chrome/renderer/pepper/pepper_uma_host.cc b/chrome/renderer/pepper/pepper_uma_host.cc
index dbf605bf2bd8eb322bf52f6218193d0041664b27..d57ce38a2a7d7e261fb0b7828f0338da9fe4e827 100644
--- a/chrome/renderer/pepper/pepper_uma_host.cc
+++ b/chrome/renderer/pepper/pepper_uma_host.cc
@@ -7,6 +7,7 @@
 #include "base/metrics/histogram.h"
 #include "base/sha1.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/renderer/chrome_content_renderer_client.h"
@@ -32,9 +33,12 @@ const char* const kWhitelistedHistogramPrefixes[] = {
     "22F67DA2061FFC4DC9A4974036348D9C38C22919"  // see http://crbug.com/390221
 };
 
-const char* const kWhitelistedPluginBaseNames[] = {
-    "libwidevinecdmadapter.so",  // see http://crbug.com/368743
-    "libpdf.so"                  // see http://crbug.com/405305
+// Name patterns in this list should be as specific as possible to avoid
+// over-whitelisting unexpected plugins.
+const char* const kWhitelistedPluginNamePatterns[] = {
+    "*widevinecdmadapter.*",  // see http://crbug.com/368743 and

[ddorwin, 2014/09/12 16:11:08]

How good is the pattern matching? Can we do something like [lib]wide...?

Is this better than just having some platform-specific code or using a constant
we already have?

[xhwang, 2014/09/12 16:33:58]

No, it only supports * and ?. Probably I can find some regex function but felt
that may be overkill...
 
I debated about that myself :) I just didn't feel like putting all three
versions of widevine cdm adapter file names in this file, which is not scalable
(imagine someone else wants to whitelist another plugins...).

I also looked at GetNativeLibraryName():
https://code.google.com/p/chromium/codesearch#chromium/src/base/native_librar...

There are a few issues:
1, it's .dylib instead of .plugin
2, We still need to support the case where we only want to whitelist a plugin on
certain platforms, e.g. libpdf.so on linux only.

+                              // http://crbug.com/410630
+    "libpdf.so"               // see http://crbug.com/405305
 };
 
 std::string HashPrefix(const std::string& histogram) {
@@ -61,8 +65,8 @@ PepperUMAHost::PepperUMAHost(content::RendererPpapiHost* host,
     allowed_origins_.insert(kPredefinedAllowedUMAOrigins[i]);
   for (size_t i = 0; i < arraysize(kWhitelistedHistogramPrefixes); ++i)
     allowed_histogram_prefixes_.insert(kWhitelistedHistogramPrefixes[i]);
-  for (size_t i = 0; i < arraysize(kWhitelistedPluginBaseNames); ++i)
-    allowed_plugin_base_names_.insert(kWhitelistedPluginBaseNames[i]);
+  for (size_t i = 0; i < arraysize(kWhitelistedPluginNamePatterns); ++i)
+    allowed_plugin_name_patterns_.insert(kWhitelistedPluginNamePatterns[i]);
 }
 
 PepperUMAHost::~PepperUMAHost() {}
@@ -99,9 +103,12 @@ bool PepperUMAHost::IsHistogramAllowed(const std::string& histogram) {
     return true;
   }
 
-  if (allowed_plugin_base_names_.find(plugin_base_name_.MaybeAsASCII()) !=
-      allowed_plugin_base_names_.end()) {
-    return true;
+  std::string plugin_base_name_string = plugin_base_name_.MaybeAsASCII();
+  std::set<std::string>::const_iterator iter =

[ddorwin, 2014/09/12 16:11:08]

Why is this outside the for loop?

[xhwang, 2014/09/12 16:33:57]

I hated the long line...  will fix :) ~~

+      allowed_plugin_name_patterns_.begin();
+  for (; iter != allowed_plugin_name_patterns_.end(); ++iter) {
+    if (MatchPattern(plugin_base_name_string, *iter))
+      return true;
   }
 
   LOG(ERROR) << "Host or histogram name is not allowed to use the UMA API.";