# `CCXT.WS.Auth.IsoPassphrase`
[🔗](https://github.com/ZenHive/ccxt_client/blob/main/lib/ccxt/ws/auth/iso_passphrase.ex#L1)

ISO Passphrase auth pattern — okx family, kucoin family, bitget.

Builds a 3-factor login frame: `apiKey`, `passphrase`, and a
`timestamp+"GET"+"/users/self/verify"` HMAC-SHA256 base64 signature.

Requires `credentials.password` (the exchange's passphrase). If missing,
returns `{:error, :passphrase_required}`.

## Example Frame (okx)

    %{
      "op" => "login",
      "args" => [
        %{
          "apiKey" => "api_key_here",
          "passphrase" => "passphrase_here",
          "timestamp" => "1699999999",
          "sign" => "base64_signature"
        }
      ]
    }

## Config

| Key | Default | Purpose |
|---|---|---|
| `:timestamp_unit` | `:seconds` | `:seconds` or `:milliseconds` |
| `:op_field` | `"op"` | Top-level field name |
| `:op_value` | `"login"` | Top-level field value |
| `:timestamp_ms_override` | (unset) | Test-only — freezes the clock |

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*Consult [api-reference.md](api-reference.md) for complete listing*