Return two values: the hash algorithm used by NARINFO and its value as a bytevector.

Return the value of a narinfo's 'Signature' field as a canonical sexp.

Return true if NARINFO1 and NARINFO2 are equivalent--i.e., if they describe the same store item. This ignores unnecessary metadata such as the Nar URL.

Select the "best" URI to download NARINFO's nar, and return three values: the URI, its compression method (a string), and the compressed file size.

When FAST-DECOMPRESSION? is true, prefer substitutes with faster decompression (typically zstd) rather than substitutes with a higher compression ratio (typically lzip).

Return the narinfo represented by STR. Assume CACHE-URI as the base URI of the cache STR originates form.

Return the sorted list of "preferred" nar URIs from NARINFO (preferred comes first) where each entry is a tuple containing: the URI, its compression method (a string), and the compressed file size.

When FAST-DECOMPRESSION? is true, prefer substitutes with faster decompression (typically zstd) rather than substitutes with a higher compression ratio (typically lzip).

If the string HASH denotes a sha256 hash, return it as a bytevector. Otherwise return #f.

Return #t if NARINFO's signature is valid and made by one of the keys in ACL.

Read a narinfo from PORT. If URL is true, it must be a string used to build full URIs from relative URIs found while reading PORT. When SIZE is true, read at most SIZE bytes from PORT; otherwise, read as much as possible.

No authentication and authorization checks are performed here!

Return two values: the first key with ID in KEYRING, and a list of associated packets (user IDs, signatures, etc.). Return #f and the empty list of ID was not found. ID must be the 64-bit key ID of the key, an integer.