Backed out changeset e84a9df80ec5 (bug 1060179)

content/media/VideoUtils.cpp

@@ -11,9 +11,7 @@
 #include "ImageContainer.h"
 #include "SharedThreadPool.h"
 #include "mozilla/Preferences.h"
-#include "mozilla/Base64.h"
-#include "nsIRandomGenerator.h"
-#include "nsIServiceManager.h"
+
 #include <stdint.h>
 
 namespace mozilla {
@@ -232,42 +230,4 @@ ExtractH264CodecDetails(const nsAString& aCodec,
   return true;
 }
 
-nsresult
-GenerateRandomPathName(nsCString& aOutSalt, uint32_t aLength)
-{
-  nsresult rv;
-  nsCOMPtr<nsIRandomGenerator> rg =
-    do_GetService("@mozilla.org/security/random-generator;1", &rv);
-  if (NS_FAILED(rv)) return rv;
-
-  // For each three bytes of random data we will get four bytes of
-  // ASCII. Request a bit more to be safe and truncate to the length
-  // we want at the end.
-  const uint32_t requiredBytesLength =
-    static_cast<uint32_t>((aLength + 1) / 4 * 3);
-
-  uint8_t* buffer;
-  rv = rg->GenerateRandomBytes(requiredBytesLength, &buffer);
-  if (NS_FAILED(rv)) return rv;
-
-  nsAutoCString temp;
-  nsDependentCSubstring randomData(reinterpret_cast<const char*>(buffer),
-                                   requiredBytesLength);
-  rv = Base64Encode(randomData, temp);
-  NS_Free(buffer);
-  buffer = nullptr;
-  if (NS_FAILED (rv)) return rv;
-
-  temp.Truncate(aLength);
-
-  // Base64 characters are alphanumeric (a-zA-Z0-9) and '+' and '/', so we need
-  // to replace illegal characters -- notably '/'
-  temp.ReplaceChar(FILE_PATH_SEPARATOR FILE_ILLEGAL_CHARACTERS, '_');
-
-  aOutSalt = temp;
-
-  return NS_OK;
-}
-
-
 } // end namespace mozilla

content/media/VideoUtils.h

@@ -257,12 +257,6 @@ ExtractH264CodecDetails(const nsAString& aCodecs,
                         int16_t& aProfile,
                         int16_t& aLevel);
 
-// Use a cryptographic quality PRNG to generate raw random bytes
-// and convert that to a base64 string suitable for use as a file or URL
-// path. This is based on code from nsExternalAppHandler::SetUpTempFile.
-nsresult
-GenerateRandomPathName(nsCString& aOutSalt, uint32_t aLength);
-
 } // end namespace mozilla
 
 #endif

content/media/android/AndroidMediaResourceServer.cpp

@@ -438,11 +438,38 @@ AndroidMediaResourceServer::AppendRandomPath(nsCString& aUrl)
   // and convert that to a base64 string for use as an URL path. This
   // is based on code from nsExternalAppHandler::SetUpTempFile.
   nsresult rv;
-  nsAutoCString salt;
-  rv = GenerateRandomPathName(salt, 16);
+  nsCOMPtr<nsIRandomGenerator> rg =
+    do_GetService("@mozilla.org/security/random-generator;1", &rv);
   if (NS_FAILED(rv)) return rv;
+
+  // For each three bytes of random data we will get four bytes of
+  // ASCII. Request a bit more to be safe and truncate to the length
+  // we want at the end.
+  const uint32_t wantedFileNameLength = 16;
+  const uint32_t requiredBytesLength =
+    static_cast<uint32_t>((wantedFileNameLength + 1) / 4 * 3);
+
+  uint8_t* buffer;
+  rv = rg->GenerateRandomBytes(requiredBytesLength, &buffer);
+  if (NS_FAILED(rv)) return rv;
+
+  nsAutoCString tempLeafName;
+  nsDependentCSubstring randomData(reinterpret_cast<const char*>(buffer),
+                                   requiredBytesLength);
+  rv = Base64Encode(randomData, tempLeafName);
+  NS_Free(buffer);
+  buffer = nullptr;
+  if (NS_FAILED (rv)) return rv;
+
+  tempLeafName.Truncate(wantedFileNameLength);
+
+  // Base64 characters are alphanumeric (a-zA-Z0-9) and '+' and '/', so we need
+  // to replace illegal characters -- notably '/'
+  tempLeafName.ReplaceChar(FILE_PATH_SEPARATOR FILE_ILLEGAL_CHARACTERS, '_');
+
   aUrl += "/";
-  aUrl += salt;
+  aUrl += tempLeafName;
+
   return NS_OK;
 }
 
@@ -450,7 +477,7 @@ nsresult
 AndroidMediaResourceServer::AddResource(mozilla::MediaResource* aResource, nsCString& aUrl)
 {
   nsCString url = GetURLPrefix();
-  nsresult rv = GenerateRandomPathName(url, 16);
+  nsresult rv = AppendRandomPath(url);
   if (NS_FAILED (rv)) return rv;
 
   {