I'm looking for a service online, able to simulate an expiring SSL certificate. I know about badssl.com, but that only seems to include an expired certificate. What I'm looking to do is to call an endpoint with a certificate expiring in something like 5 days. Possible?
I do not know about an online service tailored to your needs (you could also try to contact badssl.com and ask them if they would be willing to add your test case, as it may profit others too), but locally you can run openssl s_server and configure it to use any local certificate you would have created to be in the situation you need to test.
From its manual:
The s_server command implements a generic SSL/TLS server which listens for connections on a given port using SSL/TLS.
and:
s_server can be used to debug SSL clients. To accept connections from a web browser the command:
openssl s_server -accept 443 -www
can be used for example.
Otherwise, if you are outside of the world wide web world:
If a connection request is established with an SSL client and neither the -www nor the -WWW option has been used then normally any data received from the client is displayed and any key presses will be sent to the client.
(and follows a list of special keys for special operations).
Related
Problem Background:
As part of the Computer Networking course assignment, I have been given task of implementing a Proxy Server ( using python socket and ssl module ) that handles https communications between the browser and the origin server (The real server that my browser wants to talk to).
What I have done so far:
I have implemented the above requirement using ssl sockets and also generated self-signed 'cert.pem' 'key.pem' files.
What I need to do:
Now I just need to tell my browser (chrome 89 on kubuntu 20.04) to accept this self-signed certificate and then test the working of my proxy server.
Reading from this stackoverflow question, I can see that I have to:
(1) become my own CA (2) then sign my SSL certificate as a CA. (3) Then import the CA certificate (not the SSL certificate, which goes onto my server) into Chrome.
My confusion/question:
So if I do this, when eventually I am done with this assignment, how do I reverse all these steps to get my browser in the previous state before I had made all these changes. Also, how to reverse the "become your own CA" and also delete the SSL certificates signed by my CA.
Basically, I want my system to return to the previous state it was before I would have made all these changes.
UPDATE:
I have done the previously outlined steps but now I get an error.
Here is a snippet of my code:
serv_socket = socket(AF_INET, SOCK_STREAM)
serv_socket.bind(('', serv_port))
serv_socket.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
context = context.load_cert_chain('cert.pem', 'key.pem')
context.set_ciphers('EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH')
serv_socket.listen(10)
socket_to_browser, addr = serv_socket.accept()
conn_socket_to_browser = context.wrap_socket(socket_to_browser, server_side=True)
At the last line conn_socket_to_browser = context.wrap_socket(socket_to_browser, server_side=True) an exception is thrown: [SSL: HTTPS_PROXY_REQUEST] https proxy request (_ssl.c:1123)
What am I doing wrong ?
As glamorous as "becoming your own CA" sounds, with openssl it basically comes down to creating a self-signed certificate, and then creating a directory where some CA-specific configuration will be stored (I don't fully remember the specifics, but I think it was just some files related to CNs and serial numbers) so basically reversing the "become your own CA" step is something as mundane as deleting this directory along with the private key and self-signed certificate you were using for the CA. That's it, the CA is no more.
And for chrome returning to the previous state, you would just go the the CA list where you added the CA certificate, select it and delete it. Chrome will stop accepting certificates signed by your CA.
Regarding your new problem... In my opinion, you have developed some kind of reverse proxy (meaning that you expect normal HTTPS requests that you then redirect to the real server) but you have configured Chrome to use it as a forward proxy. In this case, Chrome does not send it a normal HTTPS request, it sends a special non-encrypted CONNECT command and only after receiving the non-encrypted response, it negotiates the TLS connection. That's why openssl says "https proxy request" because it has detected a "https proxy request" (a CONNECT command) instead of the normal TLS negotiation.
You can take a look at How can a Python proxy server (using SSL socket) pretend to be an HTTPS server and specify my own keys to get decrypted data?
It's python, but I think that you'll get the idea
I've always been an end consumer of HTTPS and have never really understood it that well but am looking to change that.
I am calling a RESTful web service over HTTPS. For example...
curl -X GET \
https://myCompanydns/rest/connect/v1.4/myEndpoint
With all my requests I send a basic authentication header i.e a username and password.
When I make these calls via my application I was expecting to have to add a certificate into like a jks (which I've had to do in the past) but on this occasion I've found that I can call the HTTPS web service without that.
For HTTPS to work I believe there is an SSL handshake? How is that happening successfully is this scenario without a jks?
Again, sorry for this beginner type question.
When doing a https://... request the client needs to verify that the servers certificate is the expected one - and not some man in the middle. This is done (among other things) by making sure that the servers certificate was issued by a trusted certificate authority (CA). Which CA is trusted is setup in the local trust store (i.e. local to the client). In the above call where no explicit trust store is given curl is using its default trust store. In the case where you've explicitly gave a jks you've provided the application with a specific trust store it should use.
For more on how the server certificates gets validated see SSL Certificate framework 101: How does the browser actually verify the validity of a given server certificate?.
Sim800 supports SSL protocol. AT command "AT+CIPSSL" sets TCP to use SSL function.
In the "sim800_series_ssl_application_note_v1.01.pdf" is noted that: "Module will automatic begin SSL certificate after TCP connected."
My Problem: What is the exact meaning of the begin SSL certificate? what does sim800 do exactly? Does sim800 get SSL certificate from website? where does sim800 save SSL certificate?
As far as I know, SIM800 has some certificates in it and when you use a TCP+SSL or HTTP+SSL connection it will automatically use those certificates.
If those certificates are not ok for you, you will need to use an SD card, save there the certificates you want and use the command AT+SSLSETCERT to set the certificate you saved on your SD card. Here you can find how to use the File System.
Usually the certificates that come with the module are enough and you won't need this. But for example they didn't work for me when I tried to communicate with Azure via MQTT. I had to encrypt the data myself using wolfSSL library and send it using TCP without SSL.
Note: Not all SIM800 modules have SD card support.
There are a very few information about sim800 and ssl certificate on the web, and like you i got a lot of questions about it.
About your questions on how does sim800 get certificate and where does it save it, it seems, according to sim800_series_ssl_application_note_v1.01.pdf, that you can create (defining your own path), write and import a ssl certificate on your own with the AT+FSCREATE, AT+FSWRITE and AT+SSLSETCERT commands. An example is provided at the paragraph 3.10.
I'm sorry, i can't answer your other questions.
Anyway, if you get further informations about sim800 and ssl, i would be grateful if you share it with me.
When you use AT+CIPSSL you tell the SIM-module to use the SSL connection with TCP. When you use +CIPSTART command->
SIM module requests the TCP connection with the server through SSL.
Server sends the Server SSL certificate.
The authenticity of that certificate is checked with internal certificate authority certificate (The one that resides inside SIM-module) which is cryptographically connected with server certificate.
If the authenticity of certificate can not be confirmed SIM-module will close the connection unless you use the command AT+SSLOPT=0,0 (which forces the SIM-module to ignore invalid certificate authentication) prior to AT+CIPSSL command.
//Key exchange
SIM-module then encrypts it's master key (already inside SIM-module cannot be changed or read) with the public key (Which is part of the already sent server certificate) and sends it back to server.
Server then encrypts it's master key with SIM-module's master-key and sends it back to SIM-module. Key exchange is now complete as both (server and SIM-module) recieved master keys.
SIM-module currently doesn't support Client authentication which means that server cannot authenticate the client. That means there must be some other option of authentication (For example in MQTT that can be username and password that only client knows)
If you want your module to be able to authenticate server you will need to create the self-signed certificate for server and certificate authority certificate (for SIM-module) which is cryptographically connected to self-signed certificate and upload them to server and SIM-module (through AT+SSLSETCERT command from SD card).
If you only want to encrypt the data traffic you can ignore invalid certificate (AT+SSLOPT=0,0) as you will recieve publickey nevertheless. But if you want to be sure about server authenticity you will need to upload right certificate to module.
1) I am trying to setup an FTPS server on my EC2 Ubuntu instance. I can only find resources to setup tutorials for an SFTP server.
2)From what I understand, the SSL certificate is only applicable to the server. When a user tries to FTPS to my server, should he/she upload a certificate or public/private key file similar to SFTP? Or only hostname, port, username, password is sufficient?
You might have better luck searching for "ftp over tls" which is another name for ftps. TLS is the successor protocol to SSL, though often still referred to casually as "SSL."
I use proftpd and I mention that primarily because their docs discuss some theory and troubleshooting techniques using openssl s_client -connect which you will find quite handy regardless of which server you deploy.
The SSL cert is only required at the server side, and if you happen to have a web server "wildcard" cert, you may be able to reuse that, and avoid purchasing a new one.
Client certs are optional; username and password will suffice in many applications. Properly configured, authentication will only happen over encrypted connections. (Don't configure the server to also operate in cleartext mode on the standard ftp port; inevitably you'll find a client who thinks they are using TLS when they are not).
If client certs are required, it is because of your policy, rather than technical reasons. You'll find that SSL client certs operate differently than SSH. Typically the client certs are signed you a certificate authority that you create, and then you trust them because they are signed by your certificate authority as opposed to your possession of their public key, as in SSH.
I'm trying to start my TURN server with TLS enabled. I use the following line to start the server:
daemon --user=$USER $TURN $OPTIONS --tls-listening-port 3478 --cert /root/cert_2014_11/my_domain_nl.crt --pkey /root/cert_2014_11/my_domain_nl.key --CA-file /root/cert_2014_11/PositiveSSLCA2.crt
The environment variables in there are set in the config file. The server works fine without TLS using the same startup line, but if I add the three SSL related arguments, the server still isn't reachable over TLS. I tried setting a different port for SLL instead of the standard port, but it still didn't work. Whatever I do, I can reach the server without SLL, but over TLS I can't reach it. The certificate chain I use if fine, I use it for our website as well.
I've run into this exact problem before. Have a look at the documentation for the --CA-file argument:
--CA-file <filename> CA file in OpenSSL format.
Forces TURN server to verify the client SSL certificates.
By default, no CA is set and no client certificate check is performed.
This argument is needed only when you will be verifying client certificates. It's not for the certificate chain for your server certificate.
Drop the --CA-file argument, keeping the --cert and --pkey arguments.
EDIT: FYI, the certificate file you give to the --cert option can contain the entire certificate chain (yours and your CA's).