blob-decoder

Hand it opaque bytes of unknown type. blob-decoder identifies what they are, decodes them, and reports scored, cited candidates — recursively unwrapping nested wrappers (a base64'd, gzip'd binary-plist is reported as the full Base64 → Gzip → BinaryPlist chain).

The decoding is delegated to mature crates (plist, base64, hex, uuid, flate2, snap, serde_json). The value this crate adds is the orchestration layer: identify → dispatch → score → recursively unwrap, plus a clean forensic result type that is honest about ambiguity.

$ B64=$(printf '{"user":"alice"}' | gzip | base64 | tr -d '\n')
$ blob-decode --string "$B64"
blob-decode: 48 bytes; 2 candidate reading(s), best first:
  [MED ] base64 text — base64 text; decodes to 36 bytes
       cite: RFC 4648 §4-5 (Base 64 / Base64url)
       decodes to 36 bytes:
    [HIGH] gzip stream — gzip stream; 16 bytes decompressed
         cite: RFC 1952 (GZIP file format)
         decodes to 16 bytes:
      [HIGH] JSON — JSON object with 1 keys
           cite: RFC 8259 (JSON)
  [LOW ] UTF-8 text — UTF-8 text preview: "H4sIAD4mUWoAA6tWKi1OLVKyUkrMyUxOVaoFAPcasFUQAAAA"
       cite: RFC 3629 (UTF-8)

The base64 text is also technically UTF-8, so that reading is offered too — at Low confidence, ranked last. blob-decoder never hides an interpretation; it scores it.

See Validation for how identification and decode are checked against independent tools and real inputs.