Issue mcp-graveyard/UXP#1349 - Stop 2xx FTP responses from causing browser to hang.

LIST and RETR still appear to work as intended on ftp:// URLs after my changes. I wasn't able to test STOR because the browser doesn't appear to support FTP uploads at this time (although our FTP implementation appears perfectly capable of doing an FTP upload.)

If I understood the issue correctly, though, what we're doing is ensuring that we receive a preliminary 100 response from the FTP server for a given action before jumping to the 200 code describing what we do if the action was completed. Even though it makes no logical sense for a server to say an action was completed before it was initiated, someone could write a really annoying FTP server that takes advantage of this fact to crash the browser if they wanted.

2 files changed, 20 insertions, 4 deletions

diff --git a/netwerk/protocol/ftp/nsFtpConnectionThread.cpp b/netwerk/protocol/ftp/nsFtpConnectionThread.cpp
index 0dae7ca921..6904bc33b6 100644
--- a/netwerk/protocol/ftp/nsFtpConnectionThread.cpp
+++ b/netwerk/protocol/ftp/nsFtpConnectionThread.cpp
@@ -82,6 +82,9 @@ nsFtpState::nsFtpState()
     , mAnonymous(true)
     , mRetryPass(false)
     , mStorReplyReceived(false)
+    , mRlist1xxReceived(false)
+    , mRstor1xxReceived(false)
+    , mRretr1xxReceived(false)  
     , mInternalError(NS_OK)
     , mReconnectAndLoginAgain(false)
     , mCacheConnection(true)
@@ -1153,15 +1156,18 @@ nsFtpState::S_list() {
 FTP_STATE
 nsFtpState::R_list() {
     if (mResponseCode/100 == 1) {
+      mRlist1xxReceived = true;
+
         // OK, time to start reading from the data connection.
         if (mDataStream && HasPendingCallback())
             mDataStream->AsyncWait(this, 0, 0, CallbackTarget());
         return FTP_READ_BUF;
     }
 
-    if (mResponseCode/100 == 2) {
+    if (mResponseCode/100 == 2 && mRlist1xxReceived) {
         //(DONE)
         mNextState = FTP_COMPLETE;
+        mRlist1xxReceived = false;
         return FTP_COMPLETE;
     }
     return FTP_ERROR;
@@ -1181,13 +1187,16 @@ nsFtpState::S_retr() {
 
 FTP_STATE
 nsFtpState::R_retr() {
-    if (mResponseCode/100 == 2) {
+    if (mResponseCode/100 == 2 && mRretr1xxReceived) {
         //(DONE)
         mNextState = FTP_COMPLETE;
+        mRretr1xxReceived = false;
         return FTP_COMPLETE;
     }
 
     if (mResponseCode/100 == 1) {
+        mRretr1xxReceived = true;
+
         if (mDataStream && HasPendingCallback())
             mDataStream->AsyncWait(this, 0, 0, CallbackTarget());
         return FTP_READ_BUF;
@@ -1262,7 +1271,7 @@ nsFtpState::S_stor() {
 
 FTP_STATE
 nsFtpState::R_stor() {
-    if (mResponseCode/100 == 2) {
+    if (mResponseCode/100 == 2 && mRstor1xxReceived) {
         //(DONE)
         mNextState = FTP_COMPLETE;
         mStorReplyReceived = true;
@@ -1270,11 +1279,12 @@ nsFtpState::R_stor() {
         // Call Close() if it was not called in nsFtpState::OnStoprequest()
         if (!mUploadRequest && !IsClosed())
             Close();
-
+        mRstor1xxReceived = false;
         return FTP_COMPLETE;
     }
 
     if (mResponseCode/100 == 1) {
+        mRstor1xxReceived = true;
         LOG(("FTP:(%x) writing on DT\n", this));
         return FTP_READ_BUF;
     }
diff --git a/netwerk/protocol/ftp/nsFtpConnectionThread.h b/netwerk/protocol/ftp/nsFtpConnectionThread.h
index b4e71bd108..cc8f0df958 100644
--- a/netwerk/protocol/ftp/nsFtpConnectionThread.h
+++ b/netwerk/protocol/ftp/nsFtpConnectionThread.h
@@ -180,6 +180,12 @@ private:
     bool                mRetryPass;     // retrying the password
     bool                mStorReplyReceived; // FALSE if waiting for STOR
                                             // completion status from server
+    bool 		mRlist1xxReceived; // TRUE if the server has sent a
+                                           // LIST 1xx response.
+    bool		mRstor1xxReceived; // TRUE if the server has sent a
+    					   // STOR 1xx response.
+    bool		mRretr1xxReceived; // TRUE if the server has sent a
+					   // RETR 1xx response.
     nsresult            mInternalError; // represents internal state errors
     bool                mReconnectAndLoginAgain;
     bool                mCacheConnection;