asp.net identity with custom password hasher

Question

so I'm trying to get asp.net to work with a custom passwordhasher. the registration works when I change the hasher with the following code

IPasswordHasher hasher = new CustomPassword();

UserManager.PasswordHasher = hasher;

but the sign in method keep saying my credentials don't exist when using the following code for the login method in the acountcontroller

IPasswordHasher hasher = new CustomPassword();

SignInManager.UserManager.PasswordHasher = hasher;

am I missing something?

Answer 1

I had a similar issue, and the answer was not obvious. This was done in.Net6 but I believe should be the same for whatever version you are using.

You need to make sure you add the passwordhasher before the call to AddIdentity

builder.Services.AddTransient<IPasswordHasher<ApplicationUser>, PasswordHasherService>();

builder.Services.AddIdentity<ApplicationUser, IdentityRole>()

SigninManager will then use the password hasher you defined instead of the default one.