Sherlouk/DebugDevice.swift

## README.md

      
    Raw
  

              README.md
            
          
    Blog post: https://blog.sidetrack.app/debugging-in-production
Creating the Certificates


Open Keychain Access


Click Keychain Access, Certificate Assistant, and Create a Certificate Authority


Provide a name, and select 'Let me override defaults'


Unselect 'Make this CA the default'


Change the validity period as necessary, I recommend setting this to a longer length (such as 10 years)


Leave the rest of the options, and click Next through the rest of the pages


To verify, click 'Show CA Certificate'


Click Keychain Access, Certificate Assistant, and Create Certificate


Set the Identity Type to 'Leaf'


Set Certificate Type to 'Custom' and choose the certificate authority we created earlier


Override defaults and set the same validity period as you wish


Set the Issuer to your certificate authority you made earlier


Leave the rest of the options, and click Next through the rest of the pages


Delete the private keys for both the certificate authority and the leaf certificate


Right click on the Leaf certificate and press 'Export'


Select the '.cer' file format


Export this and add it to your iOS project (ensuring it's target membership includes your main app)


Right click on the authority certificate and press 'Export'


Select the '.cer' file format


Export this to your project (it's good to keep it in source control) but do not add it to your app target


The leaf certificate is shipped with your application.
The authority certificate is what is installed on the device, and is what enables the SecTrustEvaluateWithError call to succeed.
Creating and Installing the Profile

Using the Apple Configurator app, click on File and New Profile.
Provide a name and other required details. Under Certificates, click Configure and select the CA certificate exported in step 19.
This will generate a profile - you can name it anything.
There are numerous ways to install the profile onto a device. At Sidetrack, we store it in a secure Google drive where we can install it from their mobile app.
Though while we've got it open, we'll do it in Configurator.
Select your device and click Add. Select your profile and confirm.
Now this adds it to your phone's storage, but you must first install it for it to be trusted. Head to your iPhone Settings, General and then VPN & Device Management.
Your custom profile should appear, in which case you can select it, tap Install, enter your passcode, tap Install again and you're done.
At this point the isDebugProfileInstalled computed variable should start passing, and you can use it to unlock functionality in your app.

  
## DebugDevice.swift
//
// DebugDevice.swift
//
// Copyright 2022 • Sidetrack Tech Limited
//

import Foundation

// This must be called on the main-thread.
var isDebugProfileInstalled: Bool {
    // DebugModeLeaf is generated in Step 16, you may need to change the name.
    guard let path = Bundle.main.path(forResource: "DebugModeLeaf", ofType: "cer") else {
        return false
    }

    // We load the certificate into memory and convert it to a certificate type using Apple's Security framework.
    guard let data = try? NSData(contentsOfFile: path) as CFData else {
        return false
    }

    let cert = SecCertificateCreateWithData(nil, data)
    let policy = SecPolicyCreateBasicX509()

    // Create a trust management object; a wrapper around the certificate
    var trust: SecTrust?
    _ = SecTrustCreateWithCertificates([ cert ] as CFArray, policy, &trust)

    guard let unwrappedTrust = trust else {
        return false
    }

    var error: CFError?

    // Verify that we can trust the certificate, this will only succeed if the device has the authority profile installed
    guard SecTrustEvaluateWithError(unwrappedTrust, &error) else {
        // You may wish to do something with the error here...
        return false
    }

    return true
}
	//
	// DebugDevice.swift
	//
	// Copyright 2022 • Sidetrack Tech Limited
	//

	import Foundation

	// This must be called on the main-thread.
	var isDebugProfileInstalled: Bool {
	// DebugModeLeaf is generated in Step 16, you may need to change the name.
	guard let path = Bundle.main.path(forResource: "DebugModeLeaf", ofType: "cer") else {
	return false
	}

	// We load the certificate into memory and convert it to a certificate type using Apple's Security framework.
	guard let data = try? NSData(contentsOfFile: path) as CFData else {
	return false
	}

	let cert = SecCertificateCreateWithData(nil, data)
	let policy = SecPolicyCreateBasicX509()

	// Create a trust management object; a wrapper around the certificate
	var trust: SecTrust?
	_ = SecTrustCreateWithCertificates([ cert ] as CFArray, policy, &trust)

	guard let unwrappedTrust = trust else {
	return false
	}

	var error: CFError?

	// Verify that we can trust the certificate, this will only succeed if the device has the authority profile installed
	guard SecTrustEvaluateWithError(unwrappedTrust, &error) else {
	// You may wish to do something with the error here...
	return false
	}

	return true
	}