From 4bc674127f88a737ed8313453f5a2ee1221e1572 Mon Sep 17 00:00:00 2001
From: Iker Luengo <ikerluengo@eprosima.com>
Date: Thu, 13 Feb 2020 08:25:22 +0100
Subject: [PATCH] Refs #7552. Only accepting ALIVE changes from unknown trusted
 writers

This is a port of #1005 from 1.9.x

* Refs #7552. Only accepting changes from unknown writers when they are ALIVE.
* Refs #7552. Added blackbox test.
---
 .../fastrtps/rtps/reader/StatelessReader.h    |  2 +-
 src/cpp/rtps/reader/StatelessReader.cpp       | 29 ++++----
 test/blackbox/BlackboxTestsDiscovery.cpp      | 67 +++++++++++++++++++
 test/blackbox/PubSubReader.hpp                |  1 +
 4 files changed, 86 insertions(+), 13 deletions(-)

diff --git a/include/fastrtps/rtps/reader/StatelessReader.h b/include/fastrtps/rtps/reader/StatelessReader.h
index 9881bb437c1..8d0f5478fb2 100644
--- a/include/fastrtps/rtps/reader/StatelessReader.h
+++ b/include/fastrtps/rtps/reader/StatelessReader.h
@@ -165,7 +165,7 @@ class StatelessReader: public RTPSReader
 
 private:
 
-    bool acceptMsgFrom(GUID_t& entityId);
+    bool acceptMsgFrom(GUID_t& entityId, ChangeKind_t change_kind);
 
     bool thereIsUpperRecordOf(GUID_t& guid, SequenceNumber_t& seq);
 
diff --git a/src/cpp/rtps/reader/StatelessReader.cpp b/src/cpp/rtps/reader/StatelessReader.cpp
index 9e9a28f039d..c273913678a 100644
--- a/src/cpp/rtps/reader/StatelessReader.cpp
+++ b/src/cpp/rtps/reader/StatelessReader.cpp
@@ -216,7 +216,7 @@ bool StatelessReader::processDataMsg(CacheChange_t *change)
 
     std::unique_lock<std::recursive_timed_mutex> lock(mp_mutex);
 
-    if(acceptMsgFrom(change->writerGUID))
+    if (acceptMsgFrom(change->writerGUID, change->kind))
     {
         logInfo(RTPS_MSG_IN,IDSTRING"Trying to add change " << change->sequenceNumber <<" TO reader: "<< getGuid().entityId);
 
@@ -317,7 +317,7 @@ bool StatelessReader::processDataFragMsg(
 
     std::unique_lock<std::recursive_timed_mutex> lock(mp_mutex);
 
-    if (acceptMsgFrom(incomingChange->writerGUID))
+    if (acceptMsgFrom(incomingChange->writerGUID, incomingChange->kind))
     {
         if (liveliness_lease_duration_ < c_TimeInfinite)
         {
@@ -431,28 +431,33 @@ bool StatelessReader::processGapMsg(
     return true;
 }
 
-bool StatelessReader::acceptMsgFrom(GUID_t& writerId)
+bool StatelessReader::acceptMsgFrom(
+        GUID_t& writerId,
+        ChangeKind_t change_kind)
 {
-    if(this->m_acceptMessagesFromUnknownWriters)
+    if (change_kind == ChangeKind_t::ALIVE)
     {
-        return true;
-    }
-    else
-    {
-        if(writerId.entityId == this->m_trustedWriterEntityId)
+        if(this->m_acceptMessagesFromUnknownWriters)
         {
             return true;
         }
-
-        for(auto it = m_matched_writers.begin();it!=m_matched_writers.end();++it)
+        else
         {
-            if((*it).guid == writerId)
+            if(writerId.entityId == this->m_trustedWriterEntityId)
             {
                 return true;
             }
         }
     }
 
+    for(auto it = m_matched_writers.begin();it!=m_matched_writers.end();++it)
+    {
+        if((*it).guid == writerId)
+        {
+            return true;
+        }
+    }
+    
     return false;
 }
 
diff --git a/test/blackbox/BlackboxTestsDiscovery.cpp b/test/blackbox/BlackboxTestsDiscovery.cpp
index 9d2217de888..00f11ae5391 100644
--- a/test/blackbox/BlackboxTestsDiscovery.cpp
+++ b/test/blackbox/BlackboxTestsDiscovery.cpp
@@ -652,3 +652,70 @@ TEST(Discovery, TwentyParticipantsSeveralEndpoints)
         ps->destroy();
     }
 }
+
+//! Regression test for support case 7552 (CRM #353)
+TEST(Discovery, RepeatPubGuid)
+{
+    PubSubReader<HelloWorldType> reader(TEST_TOPIC_NAME);
+    PubSubWriter<HelloWorldType> writer(TEST_TOPIC_NAME);
+    PubSubWriter<HelloWorldType> writer2(TEST_TOPIC_NAME);
+
+    reader
+        .history_kind(eprosima::fastrtps::KEEP_LAST_HISTORY_QOS)
+        .history_depth(10)
+        .reliability(eprosima::fastrtps::RELIABLE_RELIABILITY_QOS)
+        .participant_id(2)
+        .init();
+
+    writer
+        .history_kind(eprosima::fastrtps::KEEP_LAST_HISTORY_QOS)
+        .history_depth(10)
+        .reliability(eprosima::fastrtps::RELIABLE_RELIABILITY_QOS)
+        .participant_id(1)
+        .init();
+
+    ASSERT_TRUE(reader.isInitialized());
+    ASSERT_TRUE(writer.isInitialized());
+
+    // Wait for discovery.
+    writer.wait_discovery();
+    reader.wait_discovery();
+
+    auto data = default_helloworld_data_generator();
+    reader.startReception(data);
+
+    // Send data
+    writer.send(data);
+    // In this test all data should be sent.
+    ASSERT_TRUE(data.empty());
+    // Block reader until reception finished or timeout.
+    reader.block_for_all();
+
+    writer.destroy();
+    reader.wait_writer_undiscovery();
+    reader.wait_participant_undiscovery();
+
+    writer2
+        .history_kind(eprosima::fastrtps::KEEP_LAST_HISTORY_QOS)
+        .history_depth(10)
+        .reliability(eprosima::fastrtps::RELIABLE_RELIABILITY_QOS)
+        .participant_id(1)
+        .init();
+
+    ASSERT_TRUE(writer2.isInitialized());
+
+    writer2.wait_discovery();
+    reader.wait_discovery();
+
+    data = default_helloworld_data_generator();
+    reader.startReception(data);
+
+    // Send data
+    writer2.send(data);
+    // In this test all data should be sent.
+    ASSERT_TRUE(data.empty());
+    // Block reader until reception finished or timeout.
+    reader.block_for_all();
+}
+
+
diff --git a/test/blackbox/PubSubReader.hpp b/test/blackbox/PubSubReader.hpp
index efc7c85a107..249782985bc 100644
--- a/test/blackbox/PubSubReader.hpp
+++ b/test/blackbox/PubSubReader.hpp
@@ -293,6 +293,7 @@ class PubSubReader
         total_msgs_ = msgs;
         number_samples_expected_ = total_msgs_.size();
         current_received_count_ = 0;
+        last_seq = eprosima::fastrtps::rtps::SequenceNumber_t();
         mutex_.unlock();
 
         bool ret = false;