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N-PAMP draft-01 — Java quickstart

impl/java is the Java port of the OPEN-protocol reference library for N-PAMP draft-bubblefish-npamp-01: the wire-format and cryptographic primitives. Standard profile only (SHA-256, X25519MLKEM768, Ed25519, AES-256-GCM). Dependency-free — everything is built on the JDK (javax.crypto, java.security); there is no Maven/Gradle build, just javac.

What this port provides

src/main/java/sh/bubblefish/npamp/:

  • Npamp.java — the frame codec (36-octet header: magic NPAM, version, flags, type, channel, seq, CRC32C: Frame.marshal / Frame.unmarshal / Frame.headerPrefix, plus crc32c), the AES-256-GCM record layer (sealAes256Gcm / openAes256Gcm / deriveNonce, AAD = the 21-octet header prefix), the HKDF key schedule (hkdfExtract / hkdfExpand / hkdfExpandLabel with the "n-pamp " label prefix, deriveTrafficSecret, deriveKeyIv), and the registry code points.
  • Handshake.java (binding spec/10) — Transcript (§3), the key-schedule trunk deriveHandshakeSecret / deriveClientHandshakeSecret / deriveServerHandshakeSecret / deriveMasterSecret / deriveFinishedKey (§5), computeFinished / verifyFinished (§6.2), and signCertVerify / verifyCertVerify (§6.1, Ed25519 via the JDK's EdDSA provider).
  • Vectors.java — the cross-language conformance-vector generator (main emits JSON).

(High / Sovereign profiles, ML-KEM-1024, and ML-DSA-87 are out of scope for this open module.)

What this port does NOT provide

  • KEM operations — no X25519MLKEM768 encapsulation/decapsulation; the key-schedule trunk takes the two KEM shared secrets as inputs.
  • A TCP/TLS transport (ALPN n-pamp/2), connection management, or an RPC/MCP client. Those live in a consuming product, which composes primitives like these with its own handshake + transport.

Install

A JDK whose java.security providers include EdDSA (Ed25519) — the case for current standard OpenJDK distributions (verified with OpenJDK 21). No build tool and no third-party jars.

Run the tests

From impl/java, compile everything to a scratch dir, then run each test's main:

javac -d out src/main/java/sh/bubblefish/npamp/*.java src/test/java/sh/bubblefish/npamp/*.java

java -cp out sh.bubblefish.npamp.ConformanceTest   # 4 golden vectors + 5 property tests
java -cp out sh.bubblefish.npamp.TranscriptKat     # handshake KATs (spec/10 §3, §5, §6.2, §6.1) —
java -cp out sh.bubblefish.npamp.KeyScheduleKat    # three-leg ANCHOR/ORACLE/IMPL against the
java -cp out sh.bubblefish.npamp.FinishedKat       # pinned vectors in ../../test-vectors/v1/
java -cp out sh.bubblefish.npamp.CertVerifyKat

Each prints one ok/FAIL line per check, ends with ALL PASS, and exits non-zero on any failure. The KATs locate test-vectors/v1 by walking up from the working directory (an explicit path as args[0] overrides); the pinned vectors are SHA-256-checked inside each test (fail-loud on a swapped vector).

Two further checks need corpora that are not included in this open reference repository and are runnable only where those corpora are provided:

  • java -cp out sh.bubblefish.npamp.KatAesGcmWycheproof <aesgcm_kat.tsv> — Project Wycheproof AES-256-GCM verdicts (KatHkdf is the HKDF companion).
  • java -cp out sh.bubblefish.npamp.Vectors — emits the cross-language conformance vectors as JSON for the byte-compare drift gate (_conformance-harness/run-all-langs.sh). The generator itself runs anywhere; only the byte-compare needs the externally-provided vectors.json.

Run the example

examples/SecureRecordLayer.java composes the key schedule + record layer + frame codec into one send → receive round-trip (a Java mirror of the Go Example_secureRecordLayer):

javac -d out src/main/java/sh/bubblefish/npamp/Npamp.java examples/SecureRecordLayer.java
java  -cp out SecureRecordLayer

Expected output:

channel=1 seq=0 encrypted=true
recovered: hello over n-pamp

Conformance

The language-agnostic conformance corpus + KAT vectors live in test-vectors/v1/ (frozen in MANIFEST.sha256). This port is one of the handshake-bearing implementations graded by impl/_conformance-harness/kat-handshake-all-langs.sh; the handshake KATs grade it against NIST/RFC anchors, non-circularly.

License

Apache-2.0 — see LICENSE / NOTICE at the repository root.