URL verification

Verify URLs

URLs input from external sources are a subtle, yet common source of vulnerabilities. The key capability provided by safe to run in respect of insecure URLs is the ability to call urlVerification on a string.

The return value is true if the URL verification is safe, and false if not

Configuration

By default, no URLs are allowed:

"https://safetorun.com".urlVerification {} == false 

However, we can add an allowed host:

"https://safetorun.com".urlVerification {
    "safetorun.com".allowHost()
} == true 

Or, we can specify an entire URL:

"https://safetorun.com".urlVerification {
    "https://safetorun.com".allowUrl()
} == true 

Not recommended - but we can bypass any URL check by allowing all urls:

"https://safetorun.com".urlVerification {
    allowAnyUrl()
} == true 

Parameters

By default, no parameters are allowed;

"https://safetorun.com?param=abc".urlVerification {
    "safetorun.com".allowHost()
} == false

We can, however add some allowable configuration:

"https://safetorun.com?param=abc".urlVerification {
    "safetorun.com".allowHost()
    allowParameter {
        allowedType = AllowedType.String
        parameterName = "param"
    }
} == true 

These allowed types will only allow the correct types to be used as parameters:

"https://safetorun.com?param=abc".urlVerification {
    "safetorun.com".allowHost()
    allowParameter {
        allowedType = AllowedType.Bool
        parameterName = "param"
    }
} == false

You can allow very specific URLs if you prefer:

"https://safetorun.com?param=abc".urlVerification {
    "https://safetorun.com?param=abc".allowUrl()
} == true 

Or, you can bypass the whole check for parameters (not recommended):

"https://safetorun.com?param=abc".urlVerification {
    "safetorun.com".allowHost()
    allowAnyParameter()
} == true

Any URL will also allow parameters:

"https://safetorun.com?param=abc".urlVerification {
    allowAnyUrl()
} == true

Samples

A sample of protecting your webview from 3rd party websites:

3rd party website protection

A sample of protecting your app from third party intents:

3rd party intent protection