I have multiple Intel NUCs out in the field that I use for displaying digital signage. Out of the thousands I have in the field, a couple complain with this error:
SSL certificate problem: self signed certificate in certificate chain. More details here: http://curl.haxx.se/docs/sslcerts.html, curl performs SSL certificate verification by default, using a "bundle" of Certificate Authority (CA) public keys (CA certs). If the default bundle file isn't adequate, you can specify an alternate file using the --cacert option. If this HTTPS server uses a certificate signed by a CA represented in the bundle, the certificate verification probably failed due to a problem with the certificate (it might be expired, or the name might not match the domain name in the URL). If you'd like to turn off curl's verification of the certificate, use the -k (or --insecure) option.
I've confirmed that the cert is not expired, and the domain name matches
These units are running on Debian 7
Could the network they are on cause this issue with some sort of firewall setting?
When you visit the website what certificate is shown in the web browser? In your curl bundle is that the same certificate which is supposed to be used for SSL encryption? I'd guess no. CA will sign your cert.pem so that web browsers will show your green lock thereby authenticating your website. You most likely have an issue on the back end with the configuration of your curl bundle. You need to make sure that your server is using the CA cert not a self signed certificate like ssl-cert-snakeoil.pem for example.
Essentially your website should be using a static IPv4 address. As far as a network firewall stopping an SSL handshake from happening that may be possible, I have seen it happen on specific ports for example port 22 for ssh connections may be blocked at the network gateway for inbound traffic on a client side computer attempting a connection to a server. The SYN/ACK https://tools.ietf.org/rfc/rfc793.txt TCP handshake may time out in that type of network fire wall situation. However since you are getting an explicit response from your server about a self signed cert a firewall issue does not seem to be the problem.
Related
I have a business process which send messages to SAP via soap endpoint exposed by them.
I am using WCF-BasicHttp Send Adapter(In-Process).
As you can see below, earlier the url was http, now they have moved their system to cloud so now they have https endpoints.
I wanted to test this change from http->https, so I have modified the url to https, fill in the credentials for basic auth. it working fine in Test system without SSL Certificate, I need to make sure it wont cause any issue after moving to production system.
My Question is,
1/ Will it work in Production system too as its in TEST without SSL Certificate ?
2/ or Do I need to apply SSL for WCF-BasicHttp Adapter, if yes How can I do that ??
If you are moving to https URL, Certificate is must for SSL/TLS handshake. Many times, Certificate used by specific endpoint is signed by a third party Trusted Root CA e.g. Trustwave, DigiCert etc and these Root CA certs are already trusted on most of the systems. It’s possible in your test system, your endpoint certificate Root CA is already trusted and that’s why you did’t need to install the certificate. In order to check this, you can do following:
Browse your https service url in browser in chrome/IE
Look for Security/Lock sign to find it’s cert. Clicking the lock sign will open certificate.
Check the certificate root by going to Certification Path. You should see a chain of certificates in path. A cert can be by signed by just root CA Or by Intermediary CA first and then root CA. e.g.
—- Trustwave Root
—- Trustwave Intermediary
—- service cert
Or
—- Some Root
—- service cert
Check if Root CA is in your Trusted Root store of system. And Intermediary Cert (if applicable) is in Intermediary Cert Store. You can check this by opening certificate mmc snap-in using mmc command in Windows->Run and adding Certificates snap in of local computer.
If Root CA Cert and Intermediary Certs are not in your system store. SSL/TLS handshake will not complete successfully and BizTalk send port will not work.
If these are installed, you should be good. Otherwise install these certificates in local computer stores.
Another way to verify if endpoint certificate is trusted on a BizTalk system is to login with service account under which your send host is running and then browse the URL in IE. If you don’t get any Cert error, and URL opens such as wsdl URL, then you are good. If you get a cert error, this means end point certificate is not trusted and you need to install the certs as described above.
Some references:
View Certificate
Working with Certificates
I read that ejabberd recommends to use STARTTLS negotiation for secure connection between communicating entities. When I install ejabberd, by default it comes with a TLS certificate.
Then, why do I need to buy a certificate to install? what is the purpose of buying a new certificate from Certificate Authoririty since we have a default certificate?
When I deploy ejabberd on the machine, how the default certificate will be used for my domain? How the default certificate will be verified by client?
You can use ejabberd with SSL / STARTTLS with the provided TLS certificate. However, that certificate is only a self-signed certificate. It means that:
You will still be able to encrypt the traffic between the client and the server.
You client will not be able to check that the server is the domain it pretends to be. To be able to know that the certificate can be trusted the client need to refer to a trust authority in some way.
In the second case, it means that if an intermediate network device (i.e Wifi access point) tries to impersonate your server, it can present any self-signed certificate to the user, pretending to be your domain.
So, you can definitely use self-signed certificate to encrypt traffic, but to protect your users against man-in-the-middle type of attacks, you need to find a way to let the client now it can trust the certificate.
This can be done either by buying a certificate from a trusted authority (that will certify your certificate domain) or by making the client support a list of well defined certificates. This is called certificates pinning, however it requires to build the list of acceptable certificates into your client, which may not be possible.
It may be fine in your case, so buying a certificate is not mandatory.
However, not use the default ejabberd self-signed certificate, even if you plan using a self-signed certificate. The certificate provided with ejabberd will not match your own domain. You should at least generate your own self signed certificate that match your actual XMPP domain: How to create a self-signed certificate with openssl?
The client will verify whether the certificate is issued for the domain name of the Jabber ID (JID), the part behind the '#'. (There are other options, but they are incompatible with the policies enforced by the browser vendors against CAs and therefore not practical.)
Unless you already have a business relationship to a certificate authority (CA), I would recommend anyone to use Let's Encrypt and stay away from self-signed certificates.
Some instructions to automate this and be nice to the Let's Encrypt servers can be found here and the linked wiki pages.
Summary (assuming you are running Ubuntu 16.04 LTS, want to run it on the domain example.org and only use the certificate for ejabberd):
Create /usr/local/sbin/auto-renew-letsencrypt with the following content:
#!/bin/bash
# Renew all Let's Encrypt certificates which are due for renewal
t=`mktemp`
# Try to be quiet unless an error is returned
letsencrypt renew > $t || cat $t
# Hooks are not yet supported by `letsencrypt` shipping with Ubuntu 16.04 LTE
# Crudely emulate --renew-hook; breaks if diagnostic messages change
if grep -q "The following certs have been renewed" $t; then
cat /etc/letsencrypt/live/example.org/{privkey,fullchain}.pem > /etc/ejabberd/ejabberd.pem
service ejabberd reload
fi
rm $t
Run the following commands to create and activate the certificate and the automatic renewal
apt install letsencrypt
letsencrypt certonly --standalone --domain example.org
cat /etc/letsencrypt/live/example.org/{privkey,fullchain}.pem > /etc/ejabberd/ejabberd.pem
chown ejabberd:ejabberd /etc/ejabberd/ejabberd.pem
chmod 640 /etc/ejabberd/ejabberd.pem
chmod 755 /usr/local/sbin/auto-renew-letsencrypt
echo $(($RANDOM % 60)) $((RANDOM % 6)) "* * * root /usr/local/sbin/auto-renew-letsencrypt" > /etc/cron.d/auto-renew-letsencrypt
I'm trying to set up client certificate authentication. I was able to generate a CA-, server- and client-certificate. As long as I use Fiddler everything works as expected. However, as soon as I start using a browser it doesn't work anymore (HTTP Error 403.7 - Forbidden).
Of course I imported the client certificate in the Personal store and I made sure Client Certificate Negotiation is enabled.
I also tried openssl s_client -connect 127.0.0.1:443 -state -debug but I couldn't really make sense of the result... The only thing what's weird is that my CA doesn't show up in the Acceptable client certificate CA names section.
Anything else I could try?
Update:
I think it doesn't matter but my server certificate is set up for 127.0.0.1. Therefore I'm using https://127.0.0.1/... in my browsers.
Update2:
Using Wireshark I noticed that my servers' response depends on the client:
Fiddler (OK):
Client Hello
Server Hello, Certificate, Server Hello Done
Browser (Not OK):
Client Hello
Server Hello, Change Cipher Spec, Encrypted Handshake Message
Update3:
After enabling clientcertnegotiation the server response is different but still doesn't work:
Server Hello, Certificate
Certificate Request
Certificate, Client Key Exchange, Change Cipher Spec, Encrypted Handshake Message
My self-signed CA doesn't seem to be in the Distinguished Names list...
Update4:
SSL Settings: Checked Require SSL and Client certificates set as Required. Client cert shows up in Personal and the intended purpose is Client Authentication.
I finally found the issue and a workaround:
As mentioned in Update3, Distinguished Names doesn't contain my CA. This is because Distinguished Names has a limit of 2^14 bytes (16384 bytes). Because I do have a lot of CA installed on my machine my CA simply didn't make it in. The TLS standard would allow to send multiple messages but unfortunately Windows doesn't support this!
As mentioned here you have a few possibilities. The simplest one is this:
At your server add a DWORD (not QWORD!) value called SendTrustedIssuerList in your registry under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL and set it to 0. This will prevent your server from sending a list at all, letting the client choose from any installed client certificate.
Unfortunately I couldn't see any traces in the Event Viewer (as reported elsewhere). Therefore the issue wasn't easy to spot (I had to use Wireshark in order to check Distinguished Names).
Use the Accept option instead of the Require option of the "Client certificates" feature.
In IIS Manager, locate the Web application for which you want to change the SSL setting.
In Features View, double-click SSL Settings.
On the SSL Settings page, select the Accept option under Client certificates.
In the Actions pane, click Apply.
More info here
Client certificate should be imported in CurrentUser\My store with private key (i.e. p12 or pfx file usually).
CA certificate should be in LocalMachine\Root store so that IIS trusts all certificates issued by the CA and the CA is trusted for every user on the computer.
CRL issued by the CA should be either available through URL (specified in every end entity certificate that CA issued) or imported in LocalMachine\My store.
NOTE: openssl doesn't use windows certificate store so this will have no efect on openssl s_client -connect 127.0.0.1:443 -state
During SSL handshake, the browser downloads any intermediate certificate from the host web server using the URL provided if needed. I believe browser comes with the pre-installed certificates from public CAs having only the public key of the root certificate.
1) When calling a https url using a standalone java program [https://xyz.com ..which is using Verisign certificate], i do not need to add that Certificate to any truststore since its root public is already available in jdk's cacerts truststore file. Is this correct statement?
2) When i run the same program from application server, it requires to add all the intermediate certificate to server truststore individually. Why this works in different way.
If the trust chain for the servers certificate is: root-intermediate#1-intermediate#2-server and the client (browser) has root as trusted CA in its CA store, it needs a way to verify the servers certificate by checking the complete chain up to the root. And because the client usually has no knowledge of the intermediate CAs the server needs to provide them.
Sometimes it seems to work w/o providing these intermediate CAs. First, the browsers usually cache the intermediate CAs they got and thus if intermediate#2 is the same as already seen by another server the verification will succeed, but only for the clients who visited the other server before :(
Another way is to provide a URL inside a certificate, where the issuer certificate can be downloaded, e.g. server could provide a link to the certificate for intermediate#2, intermediate#2 could provide a link to intermediate#1. In this case the client could download the missing certificates. But, this features is not universally adopted, e.g. some browsers might provide it but SSL libraries outside of the browsers usually don't.
I have a server with an SSL certificate and clients with SSL cetificates, all are signed by the same CA, and the CA is trusted on the server and clients as a root authority.
However none of the clients I have tried (iphone, chrome, explorer) will send the client certificate when the server requests it, even though they all verify the server certificate fine. They all claim not to have the certificate.
When I look at the client certificate in the certificate/profile/store they all claim it is verified and legit, and all the certificates verify fine using openssl etc.
Does an SSL client certificate need a specific name or other details so that client browsers will know when to use it? Kinda of like how a server certificate has to specify the exact domain as the name on the certificate?
The server is an apache2.2 server, but I don't think its a problem on the servers end.
Client certificates must have appropriate Key Usage and Extended Key Usage extensions set. What is "appropriate" in your case, I don't know for sure but the number of variants in Key Usage is small and you can check various values yourself.
You surely haven't forgot about the private key which should be accessible on the client side, have you?
There's a summary of the key usage and extended key usage extensions to use in this document:
http://www.mozilla.org/projects/security/pki/nss/tech-notes/tn3.html
(Although it is for NSS, it should apply to other products.)
You could also check whether the list of accepted CAs sent by the server is configured properly. This can be seen using openssl s_client -connect the.host.name:443, for example.