tls: Added support for mbedtls_ssl_conf_read_timeout (#102)

ChangeLog

@@ -1,3 +1,8 @@
+[next]
+
+* tls: Add `mbedtls_ssl_conf_read_timeout`, for the read timeout
+configuration
+
 [2.8.0] - 2023-11-28
 
 * ci: Update wheels to mbedtls 2.28.6

src/mbedtls/_tls.pxd

@@ -115,6 +115,8 @@ cdef extern from "mbedtls/ssl.h" nogil:
         # set_handshake_timeout
         unsigned int hs_timeout_min
         unsigned int hs_timeout_max
+        # set_read_timeout
+        unsigned int read_timeout
 
         unsigned int endpoint
         unsigned int transport
@@ -247,7 +249,10 @@ cdef extern from "mbedtls/ssl.h" nogil:
         void *p_dbg
     )
 
-    # mbedtls_ssl_conf_read_timeout
+    void mbedtls_ssl_conf_read_timeout(
+        mbedtls_ssl_config *conf,
+        unsigned int timeout
+    )
     # mbedtls_ssl_conf_session_tickets_cb
     # mbedtls_ssl_conf_export_keys_cb
 
@@ -427,6 +432,7 @@ cdef class MbedTLSConfiguration:
     cdef _set_max_fragmentation_length(self, object mfl)
     cdef _set_anti_replay(self, mode)
     cdef _set_handshake_timeout(self, minimum, maximum)
+    cdef _set_read_timeout(self, timeout)
     cdef _set_cookie(self, _DTLSCookie cookie)
     cdef _set_sni_callback(self, callback)
     cdef _set_pre_shared_key(self, psk)

src/mbedtls/_tls.pyx

@@ -399,6 +399,7 @@ cdef class MbedTLSConfiguration:
         # badmac_limit
         handshake_timeout_min,
         handshake_timeout_max,
+        read_timeout,
         sni_callback,
         pre_shared_key,
         pre_shared_key_store,
@@ -423,6 +424,7 @@ cdef class MbedTLSConfiguration:
         self._set_handshake_timeout(
             handshake_timeout_min, handshake_timeout_max
         )
+        self._set_read_timeout(read_timeout)
         self._set_sni_callback(sni_callback)
         self._set_pre_shared_key(pre_shared_key)
         self._set_pre_shared_key_store(pre_shared_key_store)
@@ -479,6 +481,7 @@ cdef class MbedTLSConfiguration:
                 self.anti_replay,
                 self.handshake_timeout_min,
                 self.handshake_timeout_max,
+                self.read_timeout,
                 self.sni_callback,
                 self.pre_shared_key,
                 self.pre_shared_key_store,
@@ -802,6 +805,34 @@ cdef class MbedTLSConfiguration:
 
         return float(self._ctx.hs_timeout_max) / 1000.0
 
+    cdef _set_read_timeout(self, timeout):
+        """Set TLS/DTLS read timeout.
+        Use 0 for no timeout.
+
+        Args:
+            timeout (float, optional): read timeout in seconds.
+
+        """
+        if timeout is None:
+            return
+
+        def validate(extremum, *, default: float) -> float:
+            if extremum is None:
+                return default
+            if extremum < 0.0:
+                raise ValueError(extremum)
+            return extremum
+
+        _tls.mbedtls_ssl_conf_read_timeout(
+            &self._ctx,
+            int(1000.0 * validate(timeout, default=0))
+        )
+
+    @property
+    def read_timeout(self):
+        """Read timeout in seconds. Use 0 for no timeout. (default 0)."""
+        return float(self._ctx.read_timeout) / 1000.0
+
     cdef _set_sni_callback(self, callback):
         # PEP 543, optional, server-side only
         if callback is None:
@@ -916,6 +947,7 @@ cdef class _BaseContext:
                 anti_replay=None,
                 handshake_timeout_min=None,
                 handshake_timeout_max=None,
+                read_timeout=None,
                 sni_callback=configuration.sni_callback,
                 pre_shared_key=configuration.pre_shared_key,
                 pre_shared_key_store=configuration.pre_shared_key_store,
@@ -938,6 +970,7 @@ cdef class _BaseContext:
                 anti_replay=configuration.anti_replay,
                 handshake_timeout_min=configuration.handshake_timeout_min,
                 handshake_timeout_max=configuration.handshake_timeout_max,
+                read_timeout=configuration.read_timeout,
                 sni_callback=configuration.sni_callback,
                 pre_shared_key=configuration.pre_shared_key,
                 pre_shared_key_store=configuration.pre_shared_key_store,
@@ -991,6 +1024,7 @@ cdef class _BaseContext:
             anti_replay=self._conf.anti_replay,
             handshake_timeout_min=self._conf.handshake_timeout_min,
             handshake_timeout_max=self._conf.handshake_timeout_max,
+            read_timeout=self._conf.read_timeout,
             sni_callback=self._conf.sni_callback,
             pre_shared_key=self._conf.pre_shared_key,
             pre_shared_key_store=self._conf.pre_shared_key_store,

src/mbedtls/_tlsi.py

@@ -194,6 +194,7 @@ class TLSConfiguration:
     highest_supported_version: TLSVersion = TLSVersion.MAXIMUM_SUPPORTED
     trust_store: Optional[TrustStore] = None
     max_fragmentation_length: Optional[MaxFragmentLength] = None
+    read_timeout: float = 0.0
     sni_callback: Optional[ServerNameCallback] = None
     pre_shared_key: Optional[Tuple[str, bytes]] = None
     pre_shared_key_store: Mapping[str, bytes] = field(default_factory=dict)
@@ -250,6 +251,7 @@ def __eq__(self, other: object) -> bool:
                 self.sni_callback == other.sni_callback,
                 self.pre_shared_key == other.pre_shared_key,
                 self.pre_shared_key_store == other.pre_shared_key_store,
+                self.read_timeout == other.read_timeout,
             )
         )
 
@@ -263,6 +265,7 @@ def update(
         highest_supported_version: _Wrap[TLSVersion] = _DEFAULT_VALUE,
         trust_store: _Wrap[TrustStore] = _DEFAULT_VALUE,
         max_fragmentation_length: _Wrap[MaxFragmentLength] = _DEFAULT_VALUE,
+        read_timeout: _Wrap[float] = _DEFAULT_VALUE,
         sni_callback: _Wrap[Optional[ServerNameCallback]] = _DEFAULT_VALUE,
         pre_shared_key: _Wrap[Tuple[str, bytes]] = _DEFAULT_VALUE,
         pre_shared_key_store: _Wrap[Mapping[str, bytes]] = _DEFAULT_VALUE,
@@ -296,6 +299,7 @@ def update(
                 self.max_fragmentation_length,
             ),
             sni_callback=_unwrap(sni_callback, self.sni_callback),
+            read_timeout=_unwrap(read_timeout, self.read_timeout),
             pre_shared_key=_unwrap(pre_shared_key, self.pre_shared_key),
             pre_shared_key_store=_unwrap(
                 pre_shared_key_store,
@@ -318,6 +322,7 @@ class DTLSConfiguration:
     anti_replay: bool = True
     handshake_timeout_min: float = 1.0
     handshake_timeout_max: float = 60.0
+    read_timeout: float = 0.0
     sni_callback: Optional[ServerNameCallback] = None
     pre_shared_key: Optional[Tuple[str, bytes]] = None
     pre_shared_key_store: Mapping[str, bytes] = field(default_factory=dict)
@@ -375,6 +380,7 @@ def __eq__(self, other: object) -> bool:
                 self.anti_replay == other.anti_replay,
                 self.handshake_timeout_min == other.handshake_timeout_min,
                 self.handshake_timeout_max == other.handshake_timeout_max,
+                self.read_timeout == other.read_timeout,
                 self.sni_callback == other.sni_callback,
                 self.pre_shared_key == other.pre_shared_key,
                 self.pre_shared_key_store == other.pre_shared_key_store,
@@ -394,6 +400,7 @@ def update(
         anti_replay: _Wrap[bool] = _DEFAULT_VALUE,
         handshake_timeout_min: _Wrap[float] = _DEFAULT_VALUE,
         handshake_timeout_max: _Wrap[float] = _DEFAULT_VALUE,
+        read_timeout: _Wrap[float] = _DEFAULT_VALUE,
         sni_callback: _Wrap[ServerNameCallback] = _DEFAULT_VALUE,
         pre_shared_key: _Wrap[Tuple[str, bytes]] = _DEFAULT_VALUE,
         pre_shared_key_store: _Wrap[Mapping[str, bytes]] = _DEFAULT_VALUE,
@@ -435,6 +442,10 @@ def update(
                 handshake_timeout_max,
                 self.handshake_timeout_max,
             ),
+            read_timeout=_unwrap(
+                read_timeout,
+                self.read_timeout,
+            ),
             sni_callback=_unwrap(sni_callback, self.sni_callback),
             pre_shared_key=_unwrap(pre_shared_key, self.pre_shared_key),
             pre_shared_key_store=_unwrap(

tests/test_tls.py

@@ -553,6 +553,20 @@ def test_handshake_timeout_default(
         assert_conf_invariant(conf, handshake_timeout_min=hs_min)
         assert_conf_invariant(conf, handshake_timeout_max=hs_max)
 
+    @pytest.mark.parametrize("timeout", [1, 10, 5.3, 300])
+    def test_read_timeout_default(
+        self,
+        conf: Union[TLSConfiguration, DTLSConfiguration],
+        timeout: float,
+    ) -> None:
+        assert conf.read_timeout == 0
+        conf_ = conf.update(
+            read_timeout=timeout,
+        )
+        assert conf_.read_timeout == timeout
+
+        assert_conf_invariant(conf, read_timeout=timeout)
+
 
 class TestContext:
     @pytest.fixture(params=[Purpose.SERVER_AUTH, Purpose.CLIENT_AUTH])