Validation in deserializer (#36)

* Validation in Deserializer

Added validation in CDR deserialization: max buffer length is checked
when deserializing fields and strings are checked for null-terminator
(except for wstrings, which are serialized without null-terminator).

Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com>

* Catch exceptions in serdata functions

In serdata functions rmw_print, rmw_to_sample and rmw_from_sample
catch exceptions so that correct return code is given when functions
are called from ddsi.

Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com>

* Improve deserialisation validation

Refactored the deserialisation validation functions so that sequence
length is checked more properly and protection against overflows.
Renamed source files for exceptions so that it conforms to ros2 /
google c++ style guide.

Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com>

rmw_cyclonedds_cpp/src/deserialization_exception.cpp

@@ -0,0 +1,41 @@
+// Copyright 2018 to 2019 ADLINK Technology
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "rmw_cyclonedds_cpp/deserialization_exception.hpp"
+
+using rmw_cyclonedds_cpp::DeserializationException;
+
+DeserializationException::DeserializationException(const char * const & message)
+: Exception(message)
+{
+}
+
+DeserializationException::DeserializationException(const DeserializationException & ex)
+: Exception(ex)
+{
+}
+
+DeserializationException & DeserializationException::operator=(const DeserializationException & ex)
+{
+  if (this != &ex) {
+    Exception::operator=(ex);
+  }
+  return *this;
+}
+
+DeserializationException::~DeserializationException() throw()
+{
+}
+
+const char * const DeserializationException::DEFAULT_MESSAGE = "Invalid data";

rmw_cyclonedds_cpp/src/exception.cpp

@@ -0,0 +1,42 @@
+// Copyright 2016 Proyectos y Sistemas de Mantenimiento SL (eProsima).
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "rmw_cyclonedds_cpp/exception.hpp"
+
+using rmw_cyclonedds_cpp::Exception;
+
+Exception::Exception(const char * const & message)
+: m_message(message)
+{
+}
+
+Exception::Exception(const Exception & ex)
+: m_message(ex.m_message)
+{
+}
+
+Exception & Exception::operator=(const Exception & ex)
+{
+  m_message = ex.m_message;
+  return *this;
+}
+
+Exception::~Exception() throw()
+{
+}
+
+const char * Exception::what() const throw()
+{
+  return m_message.c_str();
+}

rmw_cyclonedds_cpp/src/rmw_node.cpp

@@ -713,31 +713,37 @@ extern "C" rmw_ret_t rmw_deserialize(
   const rosidl_message_type_support_t * type_support,
   void * ros_message)
 {
-  cycdeser sd(serialized_message->buffer, serialized_message->buffer_length);
   bool ok;
-  const rosidl_message_type_support_t * ts;
-  if ((ts =
-    get_message_typesupport_handle(type_support,
-    rosidl_typesupport_introspection_c__identifier)) != nullptr)
-  {
-    auto members =
-      static_cast<const rosidl_typesupport_introspection_c__MessageMembers *>(ts->data);
-    MessageTypeSupport_c msgts(members);
-    ok = msgts.deserializeROSmessage(sd, ros_message, nullptr);
-  } else {
+  try {
+    cycdeser sd(serialized_message->buffer, serialized_message->buffer_length);
+    const rosidl_message_type_support_t * ts;
     if ((ts =
       get_message_typesupport_handle(type_support,
-      rosidl_typesupport_introspection_cpp::typesupport_identifier)) != nullptr)
+      rosidl_typesupport_introspection_c__identifier)) != nullptr)
     {
       auto members =
-        static_cast<const rosidl_typesupport_introspection_cpp::MessageMembers *>(ts->data);
-      MessageTypeSupport_cpp msgts(members);
+        static_cast<const rosidl_typesupport_introspection_c__MessageMembers *>(ts->data);
+      MessageTypeSupport_c msgts(members);
       ok = msgts.deserializeROSmessage(sd, ros_message, nullptr);
     } else {
-      RMW_SET_ERROR_MSG("rmw_serialize: type support trouble");
-      return RMW_RET_ERROR;
+      if ((ts =
+        get_message_typesupport_handle(type_support,
+        rosidl_typesupport_introspection_cpp::typesupport_identifier)) != nullptr)
+      {
+        auto members =
+          static_cast<const rosidl_typesupport_introspection_cpp::MessageMembers *>(ts->data);
+        MessageTypeSupport_cpp msgts(members);
+        ok = msgts.deserializeROSmessage(sd, ros_message, nullptr);
+      } else {
+        RMW_SET_ERROR_MSG("rmw_serialize: type support trouble");
+        return RMW_RET_ERROR;
+      }
     }
+  } catch (rmw_cyclonedds_cpp::Exception & e) {
+    RMW_SET_ERROR_MSG_WITH_FORMAT_STRING("rmw_serialize: %s", e.what());
+    ok = false;
   }
+
   return ok ? RMW_RET_OK : RMW_RET_ERROR;
 }
 

rmw_cyclonedds_cpp/src/serdata.cpp

@@ -166,44 +166,52 @@ static struct ddsi_serdata * serdata_rmw_from_sample(
   enum ddsi_serdata_kind kind,
   const void * sample)
 {
-  const struct sertopic_rmw * topic = static_cast<const struct sertopic_rmw *>(topiccmn);
-  struct serdata_rmw * d = rmw_serdata_new(topic, kind);
-  if (kind != SDK_DATA) {
-    /* ROS2 doesn't do keys, so SDK_KEY is trivial */
-  } else if (!topic->is_request_header) {
-    cycser sd(d->data);
-    if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
-      (void) typed_typesupport->serializeROSmessage(sample, sd);
-    } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
-      (void) typed_typesupport->serializeROSmessage(sample, sd);
+  try {
+    const struct sertopic_rmw * topic = static_cast<const struct sertopic_rmw *>(topiccmn);
+    struct serdata_rmw * d = rmw_serdata_new(topic, kind);
+    if (kind != SDK_DATA) {
+      /* ROS2 doesn't do keys, so SDK_KEY is trivial */
+    } else if (!topic->is_request_header) {
+      cycser sd(d->data);
+      if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
+        (void) typed_typesupport->serializeROSmessage(sample, sd);
+      } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
+        (void) typed_typesupport->serializeROSmessage(sample, sd);
+      }
+    } else {
+      /* The "prefix" lambda is there to inject the service invocation header data into the CDR
+        stream -- I haven't checked how it is done in the official RMW implementations, so it is
+        probably incompatible. */
+      const cdds_request_wrapper_t * wrap = static_cast<const cdds_request_wrapper_t *>(sample);
+      auto prefix = [wrap](cycser & ser) {ser << wrap->header.guid; ser << wrap->header.seq;};
+      cycser sd(d->data);
+      if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
+        (void) typed_typesupport->serializeROSmessage(wrap->data, sd, prefix);
+      } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
+        (void) typed_typesupport->serializeROSmessage(wrap->data, sd, prefix);
+      }
     }
-  } else {
-    /* The "prefix" lambda is there to inject the service invocation header data into the CDR
-       stream -- I haven't checked how it is done in the official RMW implementations, so it is
-       probably incompatible. */
-    const cdds_request_wrapper_t * wrap = static_cast<const cdds_request_wrapper_t *>(sample);
-    auto prefix = [wrap](cycser & ser) {ser << wrap->header.guid; ser << wrap->header.seq;};
-    cycser sd(d->data);
-    if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
-      (void) typed_typesupport->serializeROSmessage(wrap->data, sd, prefix);
-    } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
-      (void) typed_typesupport->serializeROSmessage(wrap->data, sd, prefix);
+    /* FIXME: CDR padding in DDSI makes me do this to avoid reading beyond the bounds of the vector
+      when copying data to network.  Should fix Cyclone to handle that more elegantly.  */
+    while (d->data.size() % 4) {
+      d->data.push_back(0);
     }
+    return d;
+  } catch (rmw_cyclonedds_cpp::Exception & e) {
+    RMW_SET_ERROR_MSG(e.what());
+    return nullptr;
+  } catch (std::runtime_error & e) {
+    RMW_SET_ERROR_MSG(e.what());
+    return nullptr;
   }
-  /* FIXME: CDR padding in DDSI makes me do this to avoid reading beyond the bounds of the vector
-     when copying data to network.  Should fix Cyclone to handle that more elegantly.  */
-  while (d->data.size() % 4) {
-    d->data.push_back(0);
-  }
-  return d;
 }
 
 struct ddsi_serdata * serdata_rmw_from_serialized_message(
@@ -257,42 +265,51 @@ static bool serdata_rmw_to_sample(
   const struct ddsi_serdata * dcmn, void * sample, void ** bufptr,
   void * buflim)
 {
-  static_cast<void>(bufptr);    // unused
-  static_cast<void>(buflim);    // unused
-  const struct serdata_rmw * d = static_cast<const struct serdata_rmw *>(dcmn);
-  const struct sertopic_rmw * topic = static_cast<const struct sertopic_rmw *>(d->topic);
-  assert(bufptr == NULL);
-  assert(buflim == NULL);
-  if (d->kind != SDK_DATA) {
-    /* ROS2 doesn't do keys in a meaningful way yet */
-  } else if (!topic->is_request_header) {
-    cycdeser sd(static_cast<const void *>(d->data.data()), d->data.size());
-    if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
-      return typed_typesupport->deserializeROSmessage(sd, sample);
-    } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
-      return typed_typesupport->deserializeROSmessage(sd, sample);
-    }
-  } else {
-    /* The "prefix" lambda is there to inject the service invocation header data into the CDR
-       stream -- I haven't checked how it is done in the official RMW implementations, so it is
-       probably incompatible. */
-    cdds_request_wrapper_t * const wrap = static_cast<cdds_request_wrapper_t *>(sample);
-    auto prefix = [wrap](cycdeser & ser) {ser >> wrap->header.guid; ser >> wrap->header.seq;};
-    cycdeser sd(static_cast<const void *>(d->data.data()), d->data.size());
-    if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
-      return typed_typesupport->deserializeROSmessage(sd, wrap->data, prefix);
-    } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
-      return typed_typesupport->deserializeROSmessage(sd, wrap->data, prefix);
+  try {
+    static_cast<void>(bufptr);    // unused
+    static_cast<void>(buflim);    // unused
+    const struct serdata_rmw * d = static_cast<const struct serdata_rmw *>(dcmn);
+    const struct sertopic_rmw * topic = static_cast<const struct sertopic_rmw *>(d->topic);
+    assert(bufptr == NULL);
+    assert(buflim == NULL);
+    if (d->kind != SDK_DATA) {
+      /* ROS2 doesn't do keys in a meaningful way yet */
+    } else if (!topic->is_request_header) {
+      cycdeser sd(static_cast<const void *>(d->data.data()), d->data.size());
+      if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
+        return typed_typesupport->deserializeROSmessage(sd, sample);
+      } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
+        return typed_typesupport->deserializeROSmessage(sd, sample);
+      }
+    } else {
+      /* The "prefix" lambda is there to inject the service invocation header data into the CDR
+        stream -- I haven't checked how it is done in the official RMW implementations, so it is
+        probably incompatible. */
+      cdds_request_wrapper_t * const wrap = static_cast<cdds_request_wrapper_t *>(sample);
+      auto prefix = [wrap](cycdeser & ser) {ser >> wrap->header.guid; ser >> wrap->header.seq;};
+      cycdeser sd(static_cast<const void *>(d->data.data()), d->data.size());
+      if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
+        return typed_typesupport->deserializeROSmessage(sd, wrap->data, prefix);
+      } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
+        return typed_typesupport->deserializeROSmessage(sd, wrap->data, prefix);
+      }
     }
+  } catch (rmw_cyclonedds_cpp::Exception & e) {
+    RMW_SET_ERROR_MSG(e.what());
+    return false;
+  } catch (std::runtime_error & e) {
+    RMW_SET_ERROR_MSG(e.what());
+    return false;
   }
+
   return false;
 }
 
@@ -322,41 +339,50 @@ static bool serdata_rmw_eqkey(const struct ddsi_serdata * a, const struct ddsi_s
 static size_t serdata_rmw_print(
   const struct ddsi_sertopic * tpcmn, const struct ddsi_serdata * dcmn, char * buf, size_t bufsize)
 {
-  const struct serdata_rmw * d = static_cast<const struct serdata_rmw *>(dcmn);
-  const struct sertopic_rmw * topic = static_cast<const struct sertopic_rmw *>(tpcmn);
-  if (d->kind != SDK_DATA) {
-    /* ROS2 doesn't do keys in a meaningful way yet */
-    return static_cast<size_t>(snprintf(buf, bufsize, ":k:{}"));
-  } else if (!topic->is_request_header) {
-    cycprint sd(buf, bufsize, static_cast<const void *>(d->data.data()), d->data.size());
-    if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
-      return typed_typesupport->printROSmessage(sd);
-    } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
-      return typed_typesupport->printROSmessage(sd);
-    }
-  } else {
-    /* The "prefix" lambda is there to inject the service invocation header data into the CDR
-       stream -- I haven't checked how it is done in the official RMW implementations, so it is
-       probably incompatible. */
-    cdds_request_wrapper_t wrap;
-    auto prefix = [&wrap](cycprint & ser) {
-        ser >> wrap.header.guid; ser.print_constant(","); ser >> wrap.header.seq;
-      };
-    cycprint sd(buf, bufsize, static_cast<const void *>(d->data.data()), d->data.size());
-    if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
-      return typed_typesupport->printROSmessage(sd, prefix);
-    } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
-      auto typed_typesupport =
-        static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
-      return typed_typesupport->printROSmessage(sd, prefix);
+  try {
+    const struct serdata_rmw * d = static_cast<const struct serdata_rmw *>(dcmn);
+    const struct sertopic_rmw * topic = static_cast<const struct sertopic_rmw *>(tpcmn);
+    if (d->kind != SDK_DATA) {
+      /* ROS2 doesn't do keys in a meaningful way yet */
+      return static_cast<size_t>(snprintf(buf, bufsize, ":k:{}"));
+    } else if (!topic->is_request_header) {
+      cycprint sd(buf, bufsize, static_cast<const void *>(d->data.data()), d->data.size());
+      if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
+        return typed_typesupport->printROSmessage(sd);
+      } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
+        return typed_typesupport->printROSmessage(sd);
+      }
+    } else {
+      /* The "prefix" lambda is there to inject the service invocation header data into the CDR
+        stream -- I haven't checked how it is done in the official RMW implementations, so it is
+        probably incompatible. */
+      cdds_request_wrapper_t wrap;
+      auto prefix = [&wrap](cycprint & ser) {
+          ser >> wrap.header.guid; ser.print_constant(","); ser >> wrap.header.seq;
+        };
+      cycprint sd(buf, bufsize, static_cast<const void *>(d->data.data()), d->data.size());
+      if (using_introspection_c_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_c *>(topic->type_support.type_support_);
+        return typed_typesupport->printROSmessage(sd, prefix);
+      } else if (using_introspection_cpp_typesupport(topic->type_support.typesupport_identifier_)) {
+        auto typed_typesupport =
+          static_cast<MessageTypeSupport_cpp *>(topic->type_support.type_support_);
+        return typed_typesupport->printROSmessage(sd, prefix);
+      }
     }
+  } catch (rmw_cyclonedds_cpp::Exception & e) {
+    RMW_SET_ERROR_MSG(e.what());
+    return false;
+  } catch (std::runtime_error & e) {
+    RMW_SET_ERROR_MSG(e.what());
+    return false;
   }
+
   return false;
 }
 #endif

rmw_cyclonedds_cpp/src/serdes.cpp

@@ -32,9 +32,10 @@ cycser::cycser(std::vector<unsigned char> & dst_)
   dst.push_back(0);
 }
 
-cycdeserbase::cycdeserbase(const char * data_)
+cycdeserbase::cycdeserbase(const char * data_, size_t lim_)
 : data(data_),
   pos(0),
+  lim(lim_),
   swap_bytes(false)
 {
   /* Get the endianness byte (skip unused first byte in data[0]) */
@@ -48,13 +49,12 @@ cycdeserbase::cycdeserbase(const char * data_)
 }
 
 cycdeser::cycdeser(const void * data_, size_t size_)
-: cycdeserbase(static_cast<const char *>(data_)),
-  lim(size_ - 4)
+: cycdeserbase(static_cast<const char *>(data_), size_ - 4)
 {
 }
 
 cycprint::cycprint(char * buf_, size_t bufsize_, const void * data_, size_t size_)
-: cycdeserbase(static_cast<const char *>(data_)),
+: cycdeserbase(static_cast<const char *>(data_), size_ - 4),
   buf(buf_),
   bufsize(bufsize_)
 {