Update README files

rust/feed/README.md

@@ -17,6 +17,7 @@ FEED_NAME = "short name of the feed";
 ## Verify
 
 [Implements](./src/verify/mod.rs) a [HashSumNameLoader](./src/verify/mod.rs#L93) that loads the filenames defined in the sha256sums and verifies the corresponding hashsum. 
+Also, implements a [signature verifier](./src/verify/mod.rs#L163) for checking the signature of the sha256sums file.
 
 ### Example
 

rust/nasl-cli/README.md

@@ -59,6 +59,7 @@ Options:
 
 
 On `feed update` it will first read the `sha256sums` file within the feed directory and verify each file with the corresponding sha256sums. When the hash is correct it will execute each mentioned `*.nasl` script within that dir with `description = 1`.
+Optionally, it is possible to perform a signature verification of the sha256sums file before uploading. To enable the signature check, the environment variable `GNUPGHOME` must be set with the gnupg home directory, where the `pubring.kbx` file is stored.
 
 #### transform
 Runs nasl scripts in description mode and returns it as a json array into stdout.
@@ -73,6 +74,7 @@ Options:
 
 
 On `feed transform` it will first read the `sha256sums` file within the feed directory and verify each file with the corresponding sha256sums. When the hash is correct it will execute each mentioned `*.nasl` script within that dir with `description = 1`.
+Optionally, it is possible to perform a signature verification of the sha256sums file before the transformation. To enable the signature check, the environment variable `GNUPGHOME` must be set with the gnupg home directory, where the `pubring.kbx` file is stored.
 
 It will produce a json array in stdout in the format described within [json-storage](../json-storage/README.md).