* fix: harden JSON-RPC input parsing against malformed input and DoS
MessageFactory::create() detected batches via $input[0] === '{', which
mishandled valid-but-non-object JSON: a scalar ("5") or leading-whitespace
object silently returned [] (with a PHP warning) or could reach a foreach
over a non-array. It also had no bound on batch size, letting one small
request expand into arbitrarily many operations (amplification).
- Detect single-vs-batch from the decoded JSON type (object vs list array)
instead of the raw first byte; reject scalars and empty payloads as
InvalidInputMessageException rather than crashing or no-oping.
- Cap batch size (maxBatchSize, default 100) and reject oversized batches.
- Reject non-object batch elements as InvalidInputMessageException instead
of letting them hit a TypeError.
- Bound the StreamableHttpTransport POST body (maxBodyBytes, default 4 MiB),
returning 413, with an incremental read so unknown-size/chunked bodies
cannot exhaust memory.
* docs: document input-hardening limits in CHANGELOG and transports guide
Add CHANGELOG entries and docs/transports.md sections for the JSON-RPC
batch size cap (maxBatchSize) and the StreamableHttpTransport request
body size cap (maxBodyBytes), plus the type-based single-vs-batch
message detection.
* [Server] Add CORS, DNS rebinding and protocol version middleware
Introduce three PSR-15 middleware for `StreamableHttpTransport` exposed
through a public `StreamableHttpTransport::defaultMiddleware()` factory
composed automatically when no middleware is passed.
- `CorsMiddleware`: secure-by-default (no `Access-Control-Allow-Origin`),
configurable allowlist, reflects matching origin with `Vary: Origin`
to protect shared caches.
- `DnsRebindingProtectionMiddleware`: validates `Origin`/`Host` against
a hostname allowlist (localhost-only by default).
- `ProtocolVersionMiddleware`: rejects requests carrying an unsupported
`Mcp-Protocol-Version` header with `400 Bad Request`.
The transport no longer applies CORS via an `instanceof + array_unshift`
post-hook; the middleware parameter is nullable — `null` installs the
secure defaults, `[]` disables them, and users compose by spreading
`StreamableHttpTransport::defaultMiddleware()`. `SESSION_HEADER` and
`PROTOCOL_VERSION_HEADER` are promoted to public constants so middleware
can reuse them.
BC breaks:
- The `corsHeaders` constructor parameter is removed; the `middleware`
parameter shifts one position. Positional callers passing the old
`corsHeaders` argument must switch to named arguments or drop it.
- Default `Access-Control-Allow-Origin` is no longer `*`.
Addresses #260 (DNS rebinding), #277 (CORS extraction) and #306
(protocol version validation).
* [Server] Address review feedback on middleware defaults
- CorsMiddleware: emit Access-Control-Allow-Methods/Headers only on
preflight per CORS spec; tokenize Vary header to avoid substring
false-positives; add allowCredentials flag that emits
Access-Control-Allow-Credentials and throws when combined with
wildcard origin.
- DnsRebindingProtectionMiddleware: return plain-text 403 body
(HTTP-level rejection, not JSON-RPC); use parse_url(..., PHP_URL_HOST)
for origin parsing; drop redundant unbracketed '::1' from default
allowlist.
- ProtocolVersionMiddleware: use Error::forInvalidParams instead of
forInvalidRequest -- JSON-RPC -32602 fits header-value rejection
better.
- JsonRpcErrorResponse::create now accepts a JsonRpc\Error so callers
choose the error code.
- StreamableHttpTransport: emit a warning log when an explicit empty
middleware list is passed, so operators can spot accidental bypass
of the default security stack.
* [Server] Fix CI: switch warning-log tests to PHPUnit mocks
Replace the anonymous AbstractLogger fixture in
StreamableHttpTransportTest with `$this->createMock(LoggerInterface::class)`
so the test does not declare a `log()` signature at all. That sidesteps
both the psr/log v1 LSP incompatibility (untyped parameter) and the
phpstan `missingType.parameter` complaint in one move, and matches how
the rest of the suite (CallToolHandlerTest etc.) fakes loggers.
* Update src/Server/Transport/Http/Middleware/CorsMiddleware.php
Co-authored-by: Antoine Bluchet <soyuka@users.noreply.github.com>
---------
Co-authored-by: Antoine Bluchet <soyuka@users.noreply.github.com>
