Don't use talk_base::CreateRandomString() to generate ICE credentials.

talk_base::CreateRandomString() uses NSS internally, calling
PK11_GenerateRandom() and that sometimes fails. With this change
remoting will use base::RandBytesAsString() to generate ICE credentials.
This is mostly a workaround until we figure out why
talk_base::CreateRandomString() fails.

BUG=364689

Review URL: https://codereview.chromium.org/272543002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@269126 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 21 insertions, 4 deletions

diff --git a/remoting/protocol/libjingle_transport_factory.cc b/remoting/protocol/libjingle_transport_factory.cc
index 35769a5..fd5ba0d 100644
--- a/remoting/protocol/libjingle_transport_factory.cc
+++ b/remoting/protocol/libjingle_transport_factory.cc
@@ -4,7 +4,9 @@
 
 #include "remoting/protocol/libjingle_transport_factory.h"
 
+#include "base/base64.h"
 #include "base/callback.h"
+#include "base/rand_util.h"
 #include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/timer/timer.h"
@@ -44,6 +46,20 @@ const int kReconnectDelaySeconds = 15;
 // Get fresh STUN/Relay configuration every hour.
 const int kJingleInfoUpdatePeriodSeconds = 3600;
 
+// TODO(sergeyu): Remove this function and use talk_base::CreateRandomString()
+// when it's fixed to work reliably. See crbug.com/364689 .
+std::string CreateRandomString(int length) {
+  // Number of random bytes to generate base64 string at least |length|
+  // characters long.
+  int raw_length = (length + 1) * 3 / 4;
+  std::string base64;
+  base::Base64Encode(base::RandBytesAsString(raw_length), &base64);
+  DCHECK(static_cast<int>(base64.size()) == length ||
+         static_cast<int>(base64.size()) == length + 1);
+  base64.resize(length);
+  return base64;
+}
+
 class LibjingleStreamTransport
     : public StreamTransport,
       public base::SupportsWeakPtr<LibjingleStreamTransport>,
@@ -126,12 +142,13 @@ LibjingleStreamTransport::LibjingleStreamTransport(
     : port_allocator_(port_allocator),
       network_settings_(network_settings),
       event_handler_(NULL),
-      ice_username_fragment_(
-          talk_base::CreateRandomString(cricket::ICE_UFRAG_LENGTH)),
-      ice_password_(talk_base::CreateRandomString(cricket::ICE_PWD_LENGTH)),
+      ice_username_fragment_(CreateRandomString(cricket::ICE_UFRAG_LENGTH)),
+      ice_password_(CreateRandomString(cricket::ICE_PWD_LENGTH)),
       can_start_(false),
       channel_was_writable_(false),
       connect_attempts_left_(kMaxReconnectAttempts) {
+  DCHECK(!ice_username_fragment_.empty());
+  DCHECK(!ice_password_.empty());
 }
 
 LibjingleStreamTransport::~LibjingleStreamTransport() {
@@ -369,7 +386,7 @@ void LibjingleStreamTransport::TryReconnect() {
   --connect_attempts_left_;
 
   // Restart ICE by resetting ICE password.
-  ice_password_ = talk_base::CreateRandomString(cricket::ICE_PWD_LENGTH);
+  ice_password_ = CreateRandomString(cricket::ICE_PWD_LENGTH);
   channel_->SetIceCredentials(ice_username_fragment_, ice_password_);
 }