How do I define the password rules for Identity in ASP.NET 5 MVC 6 (vNext)?

I actually ended up figuring this out, it turns out you need to supply AddDefaultIdentity with a suitable lambda expression that configures the IdentityOptions it provides. This is done inside the ConfigureServices method within the Startup class, like so:

public class Startup {
public void ConfigureServices(IServiceCollection services) {


// Add Identity services to the services container.
services.AddDefaultIdentity<ApplicationIdentityDbContext, ApplicationUser, IdentityRole>(Configuration,
o => {
o.Password.RequireDigit = false;
o.Password.RequireLowercase = false;
o.Password.RequireUppercase = false;
o.Password.RequireNonLetterOrDigit = false;
o.Password.RequiredLength = 7;
});
}
}

Update 2:

The above was true in the beta1 versions of the framework, in the latest rc1 beta5 it has changed slightly to:

services.AddIdentity<ApplicationUser, IdentityRole>(o => {
// configure identity options
o.Password.RequireDigit = false;
o.Password.RequireLowercase = false;
o.Password.RequireUppercase = false;
o.Password.RequireNonAlphanumeric = false;
o.Password.RequiredLength = 6;
})
.AddEntityFrameworkStores<ApplicationIdentityDbContext>()
.AddDefaultTokenProviders();

in startup.cs:

   services.AddIdentity<ApplicationUser, IdentityRole>(x =>
{
x.Password.RequiredLength = 6;
x.Password.RequireUppercase = false;
x.Password.RequireLowercase = false;
x.Password.RequireNonAlphanumeric = false;
}).AddEntityFrameworkStores<ApplicationDbContext>().AddDefaultTokenProviders();

If you have set up a new Web project with Individual User Accounts go to:

App_Start -> IdentityConfig.cs

There you can edit the following defaults:

manager.PasswordValidator = new PasswordValidator
{
RequiredLength = 6,
RequireNonLetterOrDigit = true,
RequireDigit = true,
RequireLowercase = true,
RequireUppercase = true,
};

What I wanted to do was to customize the password rule so that it should contain characters from at least 2 of the following groups: lower case, upper case, digits and special symbols.

This is not something that I could do by just changing PasswordValidator options:

manager.PasswordValidator = new PasswordValidator
{
RequiredLength = 6,
RequireNonLetterOrDigit = false,
RequireDigit = false,
RequireLowercase = false,
RequireUppercase = false,
};

So instead I created a custom validator by extending IIdentityValidator...

First, create a new file CustomPasswordValidator.cs in your Extensions folder:

public class CustomPasswordValidator : IIdentityValidator<string>
{
public int RequiredLength { get; set; }
public CustomPasswordValidator(int length) {
RequiredLength = length;
}


/*
* logic to validate password: I am using regex to count how many
* types of characters exists in the password
*/
public Task<IdentityResult> ValidateAsync(string password) {
if (String.IsNullOrEmpty(password) || password.Length < RequiredLength)
{
return Task.FromResult(IdentityResult.Failed(
$"Password should be at least {RequiredLength} characters"));
}


int counter = 0;
List<string> patterns = new List<string>();
patterns.Add(@"[a-z]");                                          // lowercase
patterns.Add(@"[A-Z]");                                          // uppercase
patterns.Add(@"[0-9]");                                          // digits
// don't forget to include white space in special symbols
patterns.Add(@"[!@#$%^&*\(\)_\+\-\={}<>,\.\|""'~`:;\\?\/\[\] ]"); // special symbols


// count type of different chars in password
foreach (string p in patterns)
{
if (Regex.IsMatch(password, p))
{
counter++;
}
}


if (counter < 2)
{
return Task.FromResult(IdentityResult.Failed(
"Please use characters from at least two of these groups: lowercase, uppercase, digits and special symbols"));
}


return Task.FromResult(IdentityResult.Success);
}
}

Then go to IdentityConfig.cs, and initialize it in Create method:

manager.PasswordValidator = new CustomPasswordValidator(8 /*min length*/);
/*
// You don't need this anymore
manager.PasswordValidator = new PasswordValidator
{
RequiredLength = 6,
RequireNonLetterOrDigit = true,
RequireDigit = true,
RequireLowercase = true,
RequireUppercase = true,
};
*/

See my tutorial for more details.