Skip to content

README.md

Latest commit

 

History

History
92 lines (73 loc) · 3.14 KB

README.md

File metadata and controls

92 lines (73 loc) · 3.14 KB

RFC 9421 HTTP Message Signatures with wolfCrypt

Minimal RFC 9421 implementation using wolfCrypt Ed25519. Covers derived components (@method, @authority, @path, @query), arbitrary headers, timestamp validation, and keyid extraction. Single signature (sig1), Ed25519 only.

Quick start

# wolfSSL prerequisite
cd wolfssl && ./configure --enable-ed25519 --enable-coding && make && sudo make install

# Build and test
cd http-message-signatures
make
make test        # 17 tests including RFC 9421 B.2.6 vector
./sign_request   # standalone signing example

Client/server demo

./http_server_verify &   # terminal 1
./http_client_signed     # terminal 2

The client sends three requests: a valid signed POST (→ 200), a tampered request (→ 401), and a valid signed GET (→ 200).

API

/* Sign — outputs NUL-terminated Signature and Signature-Input header values */
int wc_HttpSig_Sign(
    const char* method, const char* authority,
    const char* path, const char* query,
    const wc_HttpHeader* headers, int headerCount,
    ed25519_key* key, const char* keyId, long created,
    char* sigOut, word32* sigOutSz,
    char* inputOut, word32* inputOutSz);

/* Extract keyid from Signature-Input */
int wc_HttpSig_GetKeyId(
    const char* signatureInput, const char* label,
    char* keyIdOut, word32* keyIdOutSz);

/* Verify — returns 0 on success; maxAgeSec=0 skips timestamp check */
int wc_HttpSig_Verify(
    const char* method, const char* authority,
    const char* path, const char* query,
    const wc_HttpHeader* headers, int headerCount,
    const char* signature, const char* signatureInput,
    const char* label, ed25519_key* pubKey, int maxAgeSec);

Typical verify flow:

1. wc_HttpSig_GetKeyId(sigInput, label, keyIdBuf, &sz)
2. my_key_store_lookup(keyIdBuf) → pubKey
3. wc_HttpSig_Verify(..., pubKey, maxAgeSec)

Limitations

  • No body protection — no content-digest (RFC 9530); signatures cover components and headers only
  • No replay prevention — maxAgeSec limits the window; nonce tracking is the caller's responsibility
  • Duplicate headers — first match wins, no folding
  • Y2038 — created uses long; overflows on platforms where long is 32-bit (all 32-bit targets and 64-bit Windows/LLP64) after 2038-01-19
  • Canonicalization — signer and verifier must agree on component representation; intermediaries that rewrite headers will break verification

Files

common/wc_http_sig.{c,h}   RFC 9421 sign/verify/getKeyId
common/wc_sf.{c,h}         RFC 8941 structured fields (subset)
sign_request.c              Standalone signing example
http_server_verify.c        Demo server with signature verification
http_client_signed.c        Demo client sending signed requests
test_vectors.c              17 tests including RFC 9421 B.2.6

References