I've been investigating the possibility of migrating to using Let's Encrypt to maintain the SSL certificates we have in place for the various resources we use for our operations. We have the following resources using SSL certificates:
Main website (www.example.com / example.com) - Hosted and maintained by a 3rd party who also maintains the SSL certificate
Client portal website (client.example.com) - IIS site hosted and maintained by us on a server located in a remote data center
FTP server (ftp.example.com) - WS_FTP Server hosted and maintained by us on a server located in a remote data center
Hardware firewall (firewall.example.com) - Local security appliance for our internal network
Remote Desktop Gateway (rd.example.com) - RDP server hosted and maintained by us on a server located locally
As indicated above, the SSL certificate for the main website (www) is maintained by the 3rd-party host, so I don't generally mess with that one. However, as you can tell, the DNS records for each of these endpoints point to a variety of different IP addresses. This is where my inexperience with the overall process of issuing and deploying SSL certificates has me a bit confused.
First of all, since I don't manage or maintain the main website, I'm currently manually generating the CSR's for each of the endpoints from the server/service that provides the endpoint - one from the IIS server, a different one from the RDP server, another from the WS_FTP server, and one from the hardware firewall. The manual process, while not excessively time-consuming, still requires me to go through several steps with different server systems requiring different processes.
I've considered using one of Let's Encrypt's free wildcard SSL certificates to cover all four of these endpoints (*.example.com), but I don't want to "interfere" with what our main website host is doing on that end. I realize the actual certificate itself is presented by the server to which the client is connecting, so it shouldn't matter (right?), but I'd probably still be more comfortable with individual SSL certificates for each of the subdomain endpoints.
So, I've been working on building an application using the Certes ACME client library in an attempt to automatically handle the entire SSL process from CSR to deployment. However, I've run into a few snags:
The firewall is secured against connections on port 80, so I wouldn't be able to serve up the HTTP-01 validation file for that subdomain (fw.example.com) on the device itself. The same is true for the FTP server's subdomain (ftp.example.com).
My DNS is hosted with a provider that does not currently offer an API (they say they're working on one), so I can't automate the process of the DNS-01 validation by writing the TXT record to the zone file.
I found the TLS-ALPN-01 validation method, but I'm not sure whether or not this is appropriate for the use case I'm trying to implement. According to the description of this method from Let's encrypt (emphasis mine):
This challenge is not suitable for most people. It is best suited to authors of TLS-terminating reverse proxies that want to perform host-based validation like HTTP-01, but want to do it entirely at the TLS layer in order to separate concerns. Right now that mainly means large hosting providers, but mainstream web servers like Apache and Nginx could someday implement this (and Caddy already does).
Pros:
It works if port 80 is unavailable to you.
It can be performed purely at the TLS layer.
Cons:
It’s not supported by Apache, Nginx, or Certbot, and probably won’t be soon.
Like HTTP-01, if you have multiple servers they need to all answer with the same content.
This method cannot be used to validate wildcard domains.
So, based on my research so far and my environment, my three biggest questions are these:
Would the TLS-ALPN-01 validation method be an effective - or even available - option for generating the individual SSL certificates for each subdomain? Since the firewall and FTP server cannot currently serve up the appropriate files on port 80, I don't see any way to use the HTTP-01 validation for these subdomains. Not being able to use an API to automate a DNS-01 validation would make that method generally more trouble than it's worth. While I could probably do the HTTP-01 validation for the client portal - and maybe the RDP server (I haven't gotten that far in my research yet) - I'd still be left with handling the other two subdomains manually.
Would I be better off trying to do a wildcard certificate for the subdomains? Other than "simplifying" the process by reducing the number of SSL certificates that need to be issued, is there any inherent benefit to going this route versus using individual certificates for each subdomain? Since the main site is hosted/managed by a 3rd-party and (again) I can't currently use an API to automate a DNS-01 validation, I suppose I would need to use an HTTP-01 validation. Based on my understanding, that means that I would need to get access/permission to create the response file, along with the appropriate directories on that server.
Just to be certain, is there any chance of causing some sort of "conflict" if I were to generate/deploy a wildcard certificate to the subdomains while the main website still used its own SSL certificate for the www? Again, I wouldn't think that to be the case, but I want to do my best to avoid introducing more complexity and/or problems into the situation.
I've responded to your related question on https://community.certifytheweb.com/t/tls-alpn-01-validation/1444/2 but the answer is to use DNS validation and my suggestion is to use Certify DNS (https://docs.certifytheweb.com/docs/dns/providers/certifydns), which is an alternative managed alternative cloud implementation of acme-dns (CNAME delegation of DNS challenge responses.
Certify DNS is compatible with most existing acme-dns clients so it can be used with acme-dns compatible clients as well as with Certify The Web (https://certifytheweb.com)
Related
We are running servers which run multiple processes each, who in turn currently communicate with each other using HTTP (Using 1-2 physical servers per client, and there are multiple clients with separate servers).
The servers are hosted locally per client.
We're thinking of migrating our nginx service, which is serving static files (multiple images, videos), to HTTP/2, in order to speed things up, as it is very common to request 1000 images at a time, which is an area where HTTP/2 excels.
For the client side we're using a chromium-based (Electron) client.
A problem arises from the above, where a TLS certificate is required when using HTTP/2 in the version of chromium we're using. Since this is a LAN there's no domain name, and even the IP addresses are not guaranteed to be static.
note: Using TLS is just a bonus, our main goal is to get the latency improvement from HTTP/2.
Is there a way around this?
The solution was to issue a self-signed certificate for a domain, which was added to the hosts file of all affected clients. The certificate authority was manually declared as trusted in all client machines.
For a more general solution, one could use a any DNS resolution option so long as it is consistent across for all clients, and any signed certificate, while a self-signed-signature would require a manual addition of the CA file to all the clients.
I am using the Let's Encrypt IIS client from https://github.com/Lone-Coder/letsencrypt-win-simple to generate a certificate for a server. Since the certificate is only valid for three months, I want it to auto-renew.
But the server for which I need that auto-renewing certificate is only bound to https:||mysubdomain.mydomain.com:443 and smtp:||mysubdomain.mydomain.com:25.
Both http:||mysubdomain.mydomain.com:80 and ftp:||mysubdomain.mydomain.com:21 point to a different server.
As you may have guessed, the error that is now thrown during the process is "The ACME server was probably unable to reach http:||mysubdomain.mydomain.com:80/.well-known/acme-challenge/abcdefgh...xyz".
It is completely clear to me why, but I can't fix it, because http:||mysubdomain.mydomain.com has to point to the other server. If the ACME server would try https:||mysubdomain.mydomain.com:443/.well-known/acme-challenge/abcdefgh...xyz, but ignore any certificate issue, he would successfully find the challenge.
Is there anything I can do, any feature I have overlooked, that would help me to get automated renewal working?
There are multiple options:
http-01
Redirect http://example.com/.well-known/acme-challenge/* to https://example.com/.well-known/acme-challenge/*, Boulder will happily follow any such redirect and ignore the provided certificate. That's the most simple way if you have access to the other server and can configure that redirect. It's a permanent redirect that you don't have to adjust, it'll be just fine every three months.
The option to use HTTPS directly has been removed due to security issues with some popular server software that uses the first host defined if some other virtual host doesn't define any HTTP host, which might lead to wrong issuances in multi-user environments aka shared hosting.
tls-sni-01
If you want to use just port 443, you can use another challenge type called tls-sni-01. But I think there's no client for Windows available yet that supports that challenge type.
dns-01
If you have control over the DNS via a simple API, you could also use the DNS challenge, it's completely independent of the port you can use.
I configured NGINX as a reverse proxy and also use it to handle HTTPS with Let’s Encrypt. Well, Let’s Encrypt certificate is about to expire within 3 months and administrator needs to configure to renew it automatically in a production environment.
This scenario works well for a single instance. But what about if I want to scale out the NGINX instance behind Amazon ELB or Route 53. It doesn't make sense to renew the certificate in each instance.
Any one have an experiences in the use case like this? Please suggest.
Thank you.
There are various options available.
The newest version of the spec includes an address parameter for http-01. You can use it, so the validation authority will choose that address to verify the domain ownership. I don't know if that's already implemented in Boulder, the software that Let's Encrypt uses.
Another option is to redirect all requests to a specific domain. http-01 follows any redirect, so you can redirect /.well-known/acme-client/* to acme.example.com or directly to an IP that runs the client.
There's the dns-01 challenge type. It works by providing a TXT record for _acme-challenge.example.com with the same payload as for http-01.
For any of those options, you need just one machine running the client. You can then write a small script that distributes your private keys and certificates to all other servers.
The official client is probably not the best client available for scripting. There are many available clients. One of those is my own client that can be used for scripting. Depending on the size of the integration you're planning, a library might be more useful.
I'm interested to purchase a wild card SSL certificate for my public domain (say example.com), so that we can run intranet web servers using a universally recognized CA (e.g., GoDaddy). I do plan to publish the DNS names publicly (e.g. internal.example.com), but their IP addresses are actually LAN addresses (e.g., 192...*). We want to use public DNS, because these web servers may actually be development laptops which travel around, and thus we will use Dynamic DNS to update. It's our intention that these web servers will only be available on the LAN each one is currently running on.
Will that work universally with all clients, e.g., TLS v1.2 ?
Thanks.
As long as the clients can route their traffic to these IP addresses, it will work (otherwise you won't get the connection, of course).
Certificate verification relies on two points:
Verifying that the certificate is genuine, trusted and valid in time.
Verifying that the identity of the certificate matches what you were looking for (host name verification).
This does not depend on how the DNS resolution mechanism. These mechanisms are also orthogonal to the SSL/TLS specifications (although they do recommend to verify the remote party's identity).
I've seen this sort of setup used on various clients and platforms (IE, Chrome, FF, Java clients on Windows/Linux/Mac) and it worked fine.
Of course, whether all implementations do this well is hard to guarantee. There might be some implementation that thinks it's a good idea to perform a reverse DNS lookup, for example.
Context
I developed an application deployed in a Glassfish 3.1. This application is accessed only by https and sometimes it must connect to third-party webservices located out the customers networks. The customer have other applications inside his network; mine is only a new one "service".
Topology approximation
Big-ip F5 is the ssl end point. The customer have in this device the valid certificate
IIS redirects by domain to the respective service
glassfish is the machine with the application (over, of course, a glassfish 3.1)
How it works
When a user try to connect to _https://somedomain the request arrives to the F5 where the SSL encryption ends; now we have a request to _http://somedomain. In the next step F5 redirects this request to the IIS and this, finally, redirects to glassfish. This petitions are successfully processed.
Points of interest
I've full control over glassfish server and S.O. of the vm where it is located. Not other applications are or will be deployed on this server; it's a dedicated server for the app and some services it needs. The Glassfish runs on a VM with a Debian distribution as S.O. This VM is provided by a VM Server but I don't know the brand, model, etc. The glassfish have the default http listeners configuration.
I don't have any more information about network and other devices and i can't access to
any configuration file of any other device. I can't modify any part of the network for my own but maybe ask, suggest or advice for a change. Network's behavior should not change.
Actually users reach the application without problem.
The used certificate is a simple domain certificate trusted by Verysign
The customer have no idea of how to solve this.
The problem
All the third party WS the application must access have an unique https access and, in some cases, the authentication required is mutual (two-way) and here we find the problem. When the application wants to connect to WS with mutual ssl authentication it sends the glassfish local keystore configuration targeted certificate. Customer wants, if possible, use the same cert for incoming and outcoming secure connections. This cert is in the F5 and i can't add to the glassfish keystore because if I do this I would be breaking Verysign contract requirements. I've been looking for a solution at google, here(stackoverflow), jita,... but only incoming traffic solutions I've found. I understand that maybe a SSL proxy is required but I haven't found any example or alternative solution for the outcoming ssl connections.
What I'm asking for
I'm not english speaker (isn't obvious?) and maybe i doesn't use the correct terms in my search terms. I can understand that this context can be a nightmare and hard to solve but I will stand... The first think I need is to know if exists a solution (or solutions) for this problem and if it (or they!) exist where or how can I find it/them. I've prepared different alternatives to negotiate with the customer but I need to known the true. I've spent tones of hours on this.
There are a couple of solutions.
1)pay verisign more money for a second "license/cert". They will be happy to take your money for the "privilege". :)
2)Create a different virtual server listening on 443 which points to a pool that has your client's server address as the pool member. Then on the virtual server, attach a serverssl profile that is configured to use the same cert you are using for the incoming connections. Then the F5 would authenticate with the same cert along with your app server would not need a client cert installed. Also, if they need to initiate a session to you, you would have to setup a virtual server with a clientssl profile that uses the same cert and requires a client cert to connect.
If your destinations may not be static addresses, then an irule(s) would have to be created to deal with that. Can be handled in 10 or later code with a DNS call in the irule and setting a node for the session to go.