std/jwt

JSON Web Tokens, HS256 (RFC 7519 / 7515), pure Milo over std/hmac and std/base64. HS256 is deterministic, so a token produced here is byte-identical to PyJWT / jsonwebtoken for the same header, payload, and secret. The payload is passed and returned as its raw JSON string — this module owns the JOSE framing, not the claim schema.

from "std/jwt" import { jwtSignHS256, jwtVerifyHS256 }

Functions

jwtSignHS256

fn jwtSignHS256(payload: &string, secret: &string): string

Signs a JSON payload string with HS256, returning a compact JWS: base64url(header).base64url(payload).base64url(HMAC-SHA256).

jwtVerifyHS256

fn jwtVerifyHS256(token: &string, secret: &string): bool

Verifies a compact HS256 JWS against the secret. Returns true iff the token has the exact header.payload.signature shape and the recomputed signature matches. The comparison is constant-time and alg is pinned to HS256 — no "alg":"none" downgrade.

let token = jwtSignHS256(&"{\"sub\":\"42\"}", &secret)
let ok = jwtVerifyHS256(&token, &secret)   // true