- `dhparam_generation` tests are no longer necessary, dropped.
Modified the remaining `dhparam` test to use multiple `nginx-proxy` images to verify correct behavior for different configs.
Tests now cover:
- Default (ffdhe4096) is used.
- Alternative via ENV (ffdhe2048) works correctly.
- Invalid group via ENV (1024-bit) fails.
- Custom DH params provided via file mount works with warning emitted.
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- `assert_log_contains`: added a `container_name` arg with `nginxproxy` as the default value. This allows multiple nginx-proxy containers to utilize this method instead.
- Extracted out the `openssl` test (_to `negotiate_cipher()`_) and modified it to be a bit more flexible. It now takes a container with optional extra args to pass to `openssl` command called, as well as the `grep` string to match. This made the original test redundant, so I've dropped it.
- Added two methods to use `negotiate_cipher()`, one verifies a DHE cipher suite was negotiated and checks that a DH emphermal key was also mentioned in the output. The other method verifies the expectation of failing to negotiate a valid cipher if DH params have not been set, while verifying that non-DHE cipher suites can be successfully negotiated.
- Added a `get_env()` method for extracting attached environments on a container. This is useful for verifying invalid `DHPARAM_BITS` values (eg `1024`-bit).
- The original `Server Temp Key` assertion was incorrect, it was expecting a value that is unrelated to DHE cipher suite support (_`X25519` is related to ECDHE_). This is due to TLS 1.3 being negotiated where you cannot use custom DH params, nor influence the negotiated cipher due to this mechanism changing from TLS 1.3. TLS 1.3 does support DH params, but it internally negotiates RFC 7919 group between server and client instead. Thus to verify expectations, the connection via `openssl` is made explicitly with TLS 1.2 instead.
