I have to Implement a digital signature in a certificate which we print as PDF in PHP.
The requirement is like that a authorized person like Registrar or Sub Registrar digitally signs a certificate. The basic idea behind implementing Digital signature is to know that:
1) Is the certificate digitally signed by the Authorized person and who was that authorized person or someone else has created it who dont have the authority.
2) Is there any changes in the certificate after the registrar/Sub-Registrar digitally signed the certificate (To stop forgery).
3) When was the document signed or when were the changes were done.
I have searched a lot on this topic put getting nothing and even not any tutorial which could guide me how to do this. I have never heard about this before but according to requirement I have to do this. So please someone guide me or help me how can I implement this in PHP. The certificate in which I have to implement this is http://crsdemo.lsipl.com/crs/web/index.php/auth/birthCertificate/view/cert/B/NzU2MjQ%3D
There are software libraries available that will enable you to digitally sign PDF files. iText is one, but there are plenty of others, too.
However all of the libraries tend to suffer from a common problem: safe-guarding the signer's digital certificate, and in particular, the certificate's private key.
If the signed PDF will ever be audited or submitted to a relying party (recipient) who wants to assure himself that the PDF was really signed by the person who is purported to have signed it, then the digital certificate (and signing system) must be a QSCD -- Qualified Signature Creation Device. (An older name for the same idea was SSCD, "Secure Signature Creation Device.")
Smart cards were the old way to create a QSCD. More modern is to use a centralized signing appliance. My company, DocuSign, makes a QSCD with an API, others do too.
Related
So I am setting up an SSO implementation FROM my website TO another site. I understand how to build the requests and sign them and all of that stuff. What I am having trouble understanding is the certificates. Who gets what certificate, to be specific. I know how to generate them, but I am not sure if I send over the certificate to the website I am signing into or if they have to generate the certificate and keystore and send us the certificate. There is a little confusion in this part of the process for me that I could use a little help in clarifying.
Since I am accessing their site, it would seem to me that they should generate the certificate and send it to us, and keep the keystore on their machine for the handshake. If I have to generate both, where is the keystore typically kept? We have a couple implementations of this on our site, but the developer that wrote them no longer works here and there is little to no documentation left behind. Also, is the certificate a self-signed certificate that can be used in production? I believe it is, but just want to be sure. Any help in clarification would be greatly appreciated.
It's public key infrastructure (PKI) so you each get the other's public key certificate. It's normally done using the SAML2 metadata profile so you can have their public key certificate.
Looks like you're an IdP if they want the attributes encrypted you need to use their public key to do that. You sign your SAMLResponse to them with your private key and they validate it with your public key. So you each generate your own keys and keep them secret as they are secret keys for signing. You exchange public keys.
You need a certificate for your login endpoint but the other party don't need to see this. They only need your public key certificate for use with the XML exchange and you need their certificate to validate the signature on the SAMLResponse (if you're an SP).
The certificate for working with the SAML XML is normally 10 year self signed.
I'm not very used to oAuth or using SSL certificates and was just recently forced to look into it for put.io API access. oAuth seems complicated, some methods ever require the end user to fill out their credientials.
So I went to search for a ready made PHP lib that has the full put.io API implemented and noticed he used a method where not even the "application secret" or "client ID" was needed.
All I had to do was feed it my "Oauth Token" value and it connected with ssl vertifypeer and a cafile - StarFieldSecureCertificationAuthority.crt
Now the question I guess is what this certificate really does or proves, and if I can really use his - or if this is something I should generate myself for the target deployment server?
Suprisingly, Google didn't help much at all - and I have still no idea how this oAuth with a certificate works, why it works, and how I can make sure that it does work. Any pointers?
Presumption
I take it this is the "ready made PHP lib" you refer to? If you have a question on what some code does with some file, it's helpful to post a link to the code and even more helpful to post your breakdown of it. If you try to read the code, you'll get better Google terms, and clearer narrower more easily answered SO questions, that have a wider application for other future visitors: A question "What does some code do" is easier to answer and may be found by people in the future that search for the same function.
SSL certificates
It's hard to understand what some API code does with a certificate if we have no understanding of what certificates are for. So lets try to get ssl explained to us. If reading the explaining answer on security.stackexchange.com comes hard to you, youtube is the dyslexics best friend.
So now we know that certificates are used to confirm identity or, in other words, for authentication.
OAuth tokens
OAuth tokens are like car keys; a secret that grants access to a car. In your case the car is put.io (the Resource Server). Some cars have separate keys for starting it, opening the trunk and opening the glove compartment. Some tokens only grant access to some of all the Owners Resources.
Basic idea is here, that we shouldn't leave carkeys left in our care out in the open and we shouldn't stick them in just any car we see. Because it's pretty easy to make a device that looks like a car and reacts like a car, but in fact is a car key copier. Trust me, it's the next big thing after credit card skimming. So we need to confirm the identity of the car, before stick our keys in. We need to authenticate the car.
It's pretty easy to make a device that looks like put.io and reacts like put.io, but in fact is a man-in-the-middle that copies tokens. So we need to authenticate put.io before we send the precious token.
Authenticating put.io
That is where the SSL certificates come in. Without repeating what we learned from the SSL section, we know we should carefully check the authenticity of the server certificate we get from, what we believe is, put.io. We need to check if the signature on that certificate comes from an authority (a CA) we trust. To do that we need the certificate of the CA. Many operating systems and browsers come pre-packed with trusted CA certificates.
Just open https://put.io in your browser and look for the certificate. Often by (right) clicking some padlock icon and some click for more information. You'll see that it is issued by 'Starfield Technologies, Inc.'
Using StarFieldSecureCertificationAuthority.crt
Now in NativeEngine.php we see:
$context = stream_context_create($contextOptions);
The ssl options require either a cafile or a capath. The easiest way for the API maintainer to be cross-platform is supplying a cafile. OS package maintainers will likely patch this and exchange it with the capath to the CA files they supply in their OS.
Can you trust it?
Now if the API maintainer has created that crt himself, he can impersonate any server if you use it. Luckily, you can easily check the fingerprint and see if it corresponds with the one in your browser. You can export the one in your browser if it doesn't.
The OAuth token is what authenticates you against the put.io API. (As you can see in this example, where no additional CA certificate is used.)
The CA certificate and the VerifyPeer setting are there to protect the integrity of the connection between your application and put.io: The library uses it to verify that the server it connected to really is put.io's, before proceeding to submit the OAuth token. Your code should also work if you disable the verification; but then your application would be vulnerable to a MITM attack and an attacker could obtain your OAuth token – and would then have access to your put.io account. (The same technique is used in HTTPS. See this question at ISSE for further details on the verification process.)
Note that your solution works for now, but the put.io API documentation states that they might start to expire OAuth tokens in the future, so in the long term you should switch to a library which is able to obtain new tokens (there's a list in this question):
Although at this time we do not expire OAuth access tokens, you should be prepared for this possibility in the future. Also remember that a user may revoke access via the put.io settings page at any time. Using /authorize will ask the user to re-authenticate their identity and reauthorize your app while giving the user the option to login under a different account.
I have written an API for my latest project. Written entirely in PHP, it currently supports web and mobile applications. We would like to expand that to desktop applications as well, but I'm not exactly sure how to enable to user to login through the desktop application, while still protecting the username and password from said application.
There are many brilliant developers on Stackoverflow, so shoot me some brilliant answers!
The application will be developed by 3rd parties, so I want to ensure they aren't able to store usernames and passwords
If the application has to send usernames and passwords, then it has to be able to have access to them, so don't use them inside the application at all.
Use OAuth. This is the solution used by quite a lot of large organisations, including Twitter.
There are many possibilities. What comes to mind:
Issue a Certificate signed by your CA and verify later, eg via the OpenSSL lib or Apache.
Use Public key encryption, eg via GnuPG lib, and grant access only to known pub keys.
Use any kind of Token based authentication or any other two factor authentication..
Just give them another set of API credentials (Secret Key, API Key)
its a desktop application, it has full access to the users keyboard and memory. if the application should have a login form where end users type in their usernames and passwords, the application has this data by definition.
the only solution would be to distribute the login-application yourself which does some sort of toked based authentication and provide the 3rd party applications a login token via your api.
oauth and other singe-sign-on systems on the web usually use an iframe or popup which comes from the system-to-login-to itself. no 3rd party website or application should be allowed to provide this input fields.
I have an android app that needs to connect frequently to the server to retrive or add in the database sensible data. I needed to verify that the calls to the server where being made from the app so I used this approach: how to verify the identity of the client from the server? which consists in a hardcoded string key in the app that's verified in the server.
But then I realized that there were tools like dex2jar, that would reveal all my code (Even with some obfuscation from proguard) in particular this hardcoded key.
Is there any more elegant and safe way to verify that the server calls are being made from my app?
PS: I'm sorry for the English, clearly I'm not a native speaker.
If it's only your client and your server, you can (and should) use mutually-authenticated SSL without purchasing anything. You control the server and the client, so each should only trust one certificate, the one belonging to the other and you don't need CAs for this purpose.
Here's the high-level approach. Create a self-signed server SSL certificate and deploy on your web server. You can use the keytool included with the Android SDK for this purpose. Then create a self-signed client and deploy that within your application in a custom keystore included in your application as a resource (keytool will generate this as well). Configure the server to require client-side SSL authentication and to only accept the client certificate you generated. Configure the client to use that client-side certificate to identify itself and only accept the one server-side certificate you installed on your server for that part of it.
A step-by-step for this is a much longer answer than is warranted here. I would suggest doing this in stages as there are resources on the web about how to deal with self-signed SSL certificate in Android, both server and client side. There is also a complete walk-through in my book, Application Security for the Android Platform, published by O'Reilly.
You'll normally store that certificate/private-key in a keystore of sometype (a KeyStore if you're using Android) and that keystore will be encrypted. That encryption is based on a password, so you'll either need to (1) store that password in your client somewhere, or (2) ask the user for the password when they start your client app. What you need to do depends on your usecase. If (2) is acceptable, then you've protected your credential against reverse engineering since it will be encrypted and the password will not be stored anywhere (but the user will need to type it in everytime). If you do (1), then someone will be able to reverse engineer your client, get the password, get the keystore, decrypt the private key and certificate, and create another client that will be able to connect to the server.
There is nothing you can do to prevent this; you can make reverse engineering your code harder (by obfuscation, etc) but you cannot make it impossible. You need to determine what the risk you are trying to mitigate with these approaches is and how much work is worth doing to mitigate it.
Have found the following example of OAuth server
http://oauth.googlecode.com/svn/code/php/OAuth_TestServer.php
But it is unclear for me
1. How I should generate certificates
How I should specify access token/access token secret/request token/request token secret,
should they stored in database? Should it regenerated for each request? What else I should store in database?
Where should I implement the verification of Access token?
Please advice
To Generate Certificates, you need to create a CSR (Certificate Signing Request)
If you have access to cPanel, then you can generate a CSR easily. If you don't then you will need to download some software to generate a CSR.
After you have your CSR, you can head over to CACert for a free certificate. However, be warned: not all modern browsers trust CACert, so you might get warnings. If you don't want this, you will have to pay for a certificate from a professional provider, like VeriSign.