Alain Knaff Reporter
	Description • 15 years ago

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-GB; rv:1.9.1.6) Gecko/20091216 Fedora/3.5.6-1.fc11 Firefox/3.5.6
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.7) Gecko/20100120 Fedora/3.0.1-1.fc11 Lightning/1.0b1 Thunderbird/3.0.1

If a mail server is unreachable (router on the path offline), thunderbird reports "connection refused" instead of "connection timed out". Confirmed by running a tcpdump alongside: no RST packet whatsoever.

Reproducible: Always

Steps to Reproduce:
1. Configure iptables on mail server to DROP packets from test client to imap port 
2. Run tcpdump on client
3. Click on a mail folders that lives on the test imap server
Actual Results:  
An error box with "connection refused" shows up after a while. Tcpdump shows no RST packet.

Expected Results:  
It should say "connection timed out" or something similar

	Alain Knaff Reporter
	Comment 1 • 14 years ago

It just occurred to me: Maybe Thunderbird is changing the messages to "similar" messages in order to be better able to translate them?

But at least in this particular case, this is not needed, as a properly localized glibc is able to supply these kind of (locally generated) messages in whatever language is needed.

Moreover, even in case translated system messages are not available, there is no point in making such a substitution if the user's has actually chosen English.

	Wayne Mery (:wsmwk)
	Comment 2 • 13 years ago

yeah, i do believe this is a duplicate

	Alain Knaff Reporter
	Comment 3 • 13 years ago

Still an issue in 7.0.1 .

If this is a duplicate of which bug number would it be a duplicate?

	ISHIKAWA, Chiaki
	Comment 4 • 8 years ago

*could* be this code: different errors are bundled into NS_ERROR_CONNECTION_REFUSED.
(But there may be other places where the problem may arise, also.)


line 153 of https://dxr.mozilla.org/comm-central/source/mozilla/netwerk/base/nsSocketTransport2.cpp


    case PR_CONNECT_REFUSED_ERROR:
    // We lump the following NSPR codes in with PR_CONNECT_REFUSED_ERROR. We
    // could get better diagnostics by adding distinct XPCOM error codes for
    // each of these, but there are a lot of places in Gecko that check
    // specifically for NS_ERROR_CONNECTION_REFUSED, all of which would need to
    // be checked.
    case PR_NETWORK_UNREACHABLE_ERROR:
    case PR_HOST_UNREACHABLE_ERROR:
    case PR_ADDRESS_NOT_AVAILABLE_ERROR:
    // Treat EACCES as a soft error since (at least on Linux) connect() returns
    // EACCES when an IPv6 connection is blocked by a firewall. See bug 270784.
    case PR_NO_ACCESS_RIGHTS_ERROR:
        rv = NS_ERROR_CONNECTION_REFUSED;
        break;

That is bad.

We can rewrite code where Gecko checks specifically for NS_ERROR_CONNECTION_REFUSED

we can define a function like the following:

bool
Is_NS_ERROR_CONNECTION_REFUSED_or_friends(nserror e) {
  switch (e) {
  default: return false;
      break;
  case PR_CONNECT_REFUSED_ERROR:
    // We lump the following NSPR codes in with PR_CONNECT_REFUSED_ERROR. We
    // could get better diagnostics by adding distinct XPCOM error codes for
    // each of these, but there are a lot of places in Gecko that check
    // specifically for NS_ERROR_CONNECTION_REFUSED, all of which would need to
    // be checked.
  case PR_NETWORK_UNREACHABLE_ERROR:
  case PR_HOST_UNREACHABLE_ERROR:
  case PR_ADDRESS_NOT_AVAILABLE_ERROR:
    // Treat EACCES as a soft error since (at least on Linux) connect() returns
    // EACCES when an IPv6 connection is blocked by a firewall. See bug 270784.
  case PR_NO_ACCESS_RIGHTS_ERROR:
    return true;
  }
}
 
then

modify

error_code == NS_ERROR_CONNECTION_REFUSED => Is_NS_ERROR_CONNECTION_REFUSED_or_friends(error_code)

and

error_code != NS_ERROR_CONNECTION_REFUSED => (! Is_NS_ERROR_CONNECTION_REFUSED_or_friends(error_code))

The above should fix the issue.

There are ONLY 29 places where NS_ERROR_CONNECTION_REFUSED appears in C-C source tree (actually they are all under M-C portion) and about half a dozen is where NS_ERROR_CONNECTION_REFUSED is checked by "==".
So should be doable.