Add `Store::isTrustedClient()`

This function returns true or false depending on whether the Nix client
is trusted or not. Mostly relevant when speaking to a remote store with
a daemon.

We include this information in `nix ping store` and `nix doctor`

Co-Authored-By: John Ericson <John.Ericson@Obsidian.Systems>

1 files changed, 12 insertions, 0 deletions

diff --git a/src/libstore/http-binary-cache-store.cc b/src/libstore/http-binary-cache-store.cc
index 238fd1d98..85c5eed4c 100644
--- a/src/libstore/http-binary-cache-store.cc
+++ b/src/libstore/http-binary-cache-store.cc
@@ -194,6 +194,18 @@ protected:
             }});
     }
 
+    /**
+     * This isn't actually necessary read only. We support "upsert" now, so we
+     * have a notion of authentication via HTTP POST/PUT.
+     *
+     * For now, we conservatively say we don't know.
+     *
+     * \todo try to expose our HTTP authentication status.
+     */
+    std::optional<TrustedFlag> isTrustedClient() override
+    {
+        return std::nullopt;
+    }
 };
 
 static RegisterStoreImplementation<HttpBinaryCacheStore, HttpBinaryCacheStoreConfig> regHttpBinaryCacheStore;