I'm trying to write a ftp client.
I have two ftp servers. The first server is a standard FTP server from Microsoft. The second server was written in the organization where I work.
My program with the second server works well.
But my program is the first server receives the error: "451 The parameter is incorrect".
What can be wrong?
I use Qt 4.8.4, Windows 7.
...
switch(cod) {
case 220:
user=sett.value("userFTP",QString("anonymous")).toString();
logMessage(codec1->toUnicode("Авторизация пользователя ")+user);
buf = QByteArray::fromRawData("USER ",5) + "\n";
sock->write(buf);
logMessage(buf);
break;
...
I have found the bug. I used ASCII. but I had to use the Latin 1.
Related
We have a client and server communicating each other with grpc. Previously the server was running on Windows Server, and the client running on Linux or MacOS. Everything works perfectly until we migrate the server from Windows Server to a docker container.
Then we observed some weird tcp broken when we send a large amount of request from client to server.
Then we dig into the grpc arena and run our client and server with GRPC_VERBOSITY=info and GRPC_TRACE=tcp. Then we found that the disconnection was caused from the server side, with error message below:
tcp_custom.cc:218] write complete on 029FCC20: error={"created":"#1594210168.896000000","description":"TCP Write failed","file":"d:\a\grpc-node\grpc-node\packages\grpc-native-core\deps\grpc\src\core\lib\iomgr\tcp_uv.cc","file_line":72,"grpc_status":14,"os_error":"message too long"}
So my question is what does the os_error: message too long really means? What is the next step for me to investigate?
Linked issue
The string "message too long" is the error message for the error code UV_EMSGSIZE, which corresponds to the Linux error code EMSGSIZE. That appears to generally mean that gRPC is trying to write a buffer that is too large to the socket, but I'm not sure what exactly could trigger that.
I currently have a Java Applet running on my web page that communicates to a display pole via COM1. However since the Java update I can no longer run self-signed Java Applets and I figure it would just be easier to send an AJAX request back to the server and have the server send a response to a TCP port on the computer...the computer would need a TCP > COM virtual adapter. How do I install a virtual adapter to go from a TCP port to COM1?
I've looked into com0com and that is just confusing as hell to me, and I don't see how to connect any ports to COM1. I've tried tcp2com but it doesn't seem to install the service in Windows 7 x64. I've tried com2tcp and the interface seems like it WOULD work (I haven't tested), but I don't want an app running on the desktop...it needs to be a service that runs in the background.
So to summarize how it would work:
Web page on comp1 sends AJAX request to server
Server sends text response to comp1 on port 999
comp1 has virtual COM port listening on port 999, sends data to COM1
pole displays data
EDIT: I'm using Win 7 x64 and tcp2com doesn't work as a service. I tried using srvany but I get an error stating that the application started then stopped. If I use powershell and pass the tcp2com as an argument, it doesn't quit but it also doesn't run. So I nixed the whole 'service' deal and put the command: powershell -windowstyle hidden "tcp2com --test tcp/999 com1" and it works...sort of. The characters that get sent are all effed. I can write "echo WTF > COM1" on another computer which has COM2TCP (different vendor) and it'll come up as a single block on the POS display pole. However if I use COM2TCP on both the server and client machines, everything works fine...but that's only a trial version and it costs several hundred dollars! On another note, is there a way to send the raw text over IP without having to use another Virtual COM > IP adapter on another computer? Sort of like how curl works but different...?
After somewhat of an exhaustive search, I came across a program called 'piracom'. It's a very simple app that lets you specify port settings for the express purpose of connecting a serial port to an listening port over the network. So this is IP > Serial. For Serial > IP I used HW-VSP3-Single as even on the piracom website it said it's compatible! I've tested and it works!
I just put a shortcut to piracom in the startup folder of my user account; the app runs off of a .ini that it updates every time you make a change...so if you run the server and hide it, on the next reboot of the pc it'll start up running and hidden with all prior settings. Easy.
Now it's a matter of installing HW-VSP3 on the server and making a method on the Rails app which will write to the virtual COM port. The only issue I can see right now is that writing echo \14Test This! > COM3 actually prints the \14...if I do that in my Java applet, it sends the "go to beginning" signal.
Addendum 1: The \14 problem was fixed by using the serialport gem for RoR. I created a method in a controller that returned head :no_content and then send data to the COM port. Calls to this method were made via jQuery's $.Ajax, using "HEAD" HTTP method. Apparently though I had to add the GET verb in Rails routes because the HEAD option isn't supported for some gimpy reason.
Addendum 2: Some garbage data was being sent to the display pole at the end of the string...turns out I needed to turn off the "NVT" option in HW-VSP3. Also keep in mind that firewalls need to be modified to allow communication.
There are openssl server and Qt client using QSslSocket.
When client connected to server server shows no OPENSSL_Applink and shuts down. But with OpenSSL client server works correct. What can be a reason?
#include <openssl/applink.c>
Including applink.c will solve the problem. Please check OpenSSL FAQ
Basically we get this error only if we use any file handling APIs like d2i_X509. I was getting assert failure in applink.c while using this API in windows VC8.0. Later I have done fopen separately and called d2i_X509_fp API.
So, I used the example on http://www.jcraft.com/jsch/examples/Sftp.java and I was trying to connect to ftp.secureftp-test.com.
That destination is a valid testing SFTP server (as mentioned in secureftp-test dot com/). I confirmed it by connecting to the server through nautilus. I also made sure that the password on my program was correct as well.
But, when I run the program and it hits session.connect(), it just says "INFO: Connection established" then it becomes quiet for a minute then it return:
"com.jcraft.jsch.JSchException: connection is closed by foreign host"
I am pretty sure that it got stuck in the while loop of the library but I do not know why. I tried it against my local ftp server and it also had the same problem.
During the quiet moment, I can type. But pressing enter does not send anything to the server.
Has anyone heard or seen the same problem?
Okay, it seems that secureftp-test.com is NOT an sftp server. That is ftps server.
What I did instead was creating my own sftp:
http://wiki.vpslink.com/Configuring_vsftpd_for_secure_connections_(TLS/SSL/SFTP)
Then run the example code but making sure that I have these lines before doing session.connect:
String knownHostsFilename = "/home/yourname/.ssh/known_hosts";
jsch.setKnownHosts(knownHostsFilename);
I am developing a solution which will utilize msmq to transmit data between two machines. Due to the seperation of said machines, we need to use HTTP transport for the messages.
In my test environment I am using a Windows 7 x64 development machine, which is attempting to send messages using a homebrew app to any of several test machines I have control over.
All machines are either windows server 2003 or server 2008 with msmq and msmq http support installed.
For any test destination, I can use the following queue path name with success:
FORMATNAME:DIRECT=TCP:[machine_name_or_ip]\private$\test_queue
But for any test destination, the following always fails
FORMATNAME:DIRECT=$/test_queue
I have used all permutations of machine names/ips available. I have created mappings using the method described at this blog post. All result in the same HTTP Error: 400.
The following is the code used to send messages:
MessageQueue mq = new MessageQueue(queuepath);
System.Messaging.Message msg = new System.Messaging.Message
{
Priority = MessagePriority.Normal,
Formatter = new XmlMessageFormatter(),
Label = "test"
};
msg.Body = txtMessageBody.Text;
msg.UseDeadLetterQueue = true;
msg.UseJournalQueue = true;
msg.AcknowledgeType = AcknowledgeTypes.FullReachQueue | AcknowledgeTypes.FullReceive;
msg.AdministrationQueue = new MessageQueue(#".\private$\Ack");
if (SendTransactional)
mq.Send(msg, MessageQueueTransactionType.Single);
else
mq.Send(msg);
Additional Information: in the IIS logs on the destination machines I can see each message I send being recorded as a POST with a status code of 200.
I am open to any suggestions.
The problem can be caused by the IP address of the destination server having been NAT'ed through a Firewall.
In this case the IIS server receives the message okay and passes it on to MSMQ. MSMQ then reads the message and sees the destination of the message as being something different than the known IP addresses of the server. At this point MSMQ rejects the message and IIS returns a HTTP status 400.
Fortunately the solution is fairly straightforward. Look in %windir%\System32\msmq\mapping. This folder can contain a bunch of xml files (often sample files are provided) that each contain mappings between one address and another. The name of the file can be anything you like, here is an example of the xml formatted contents:
<redirections xmlns="msmq-queue-redirections.xml">
<redirection>
<from>http://external_host/msmq/external_queue</from>
<to>http://internal_host/msmq/internal_queue</to>
</redirection>
</redirections>
The MSMQ service then needs restarting to pickup the new configuration, for instance from the command line:
net stop msmq
net start msmq
References:
http://blogs.msdn.com/b/johnbreakwell/archive/2008/01/29/unable-to-send-msmq-3-0-http-messages.aspx
http://msdn.microsoft.com/en-us/library/ms701477(v=vs.85).aspx
Maybe you have to encode the $ as %24.