I have run headfirst into this reject error from exim4:
2010-02-15 01:46:05 SMTP protocol synchronization error (input sent without waiting for greeting): rejected connection from H=ender [192.168.20.49] input="HELO 192.168.20.49\r\n"
I have modified my exim4 config to not enforce sync, like so:
smtp_enforce_sync='false'
acl_smtp_connect = nosync nosync:
control = no_enforce_sync
accept
But that doesn't seem to matter. What makes less sense to me is why I'm getting the 554 in the first place. I send a HELO, I wait for a response, and somehow in the midst of that, I manage to generate the "554 Error"
What am I doing wrong in the code below, that makes this fail 99% of the time (yes, it has worked twice). Yes, the socket is blocking, I hang in recv for ~5 seconds waiting for the rejection. On the 2 times when it has worked, it didn't pause at all.
I've tried sending EHLO instead of HELO, no better luck. I've even had grief getting a telnet session to connect and say HELO. However, i can use python smtp (from another machine) to send emails just fine against this same server!
hSocket = _connectServerSocket(server, port);
if (hSocket != INVALID_SOCKET) {
BYTE sReceiveBuffer[4096];
int iLength = 0;
int iEnd = 0;
char buf[4096];
strcpy(buf, "HELO ");
strcat(buf, "192.168.20.49");
strcat(buf, "\r\n");
printf("%s", buf);
if (send(hSocket, (LPSTR)buf, strlen(buf), NO_FLAGS) == SOCKET_ERROR) {
printf("Socket send error: %d\r\n", WSAGetLastError());
return (false);
}
iLength = recv(hSocket,
(LPSTR)sReceiveBuffer+iEnd,sizeof(sReceiveBuffer)-iEnd,
NO_FLAGS);
iEnd += iLength;
sReceiveBuffer[iEnd] = '\0';