Added Loopback::matches_response.

include/tins/loopback.h

@@ -86,6 +86,15 @@ public:
      */
     PDUType pdu_type() const { return pdu_flag; }
     
+    /** 
+     * \brief Check wether ptr points to a valid response for this PDU.
+     *
+     * \sa PDU::matches_response
+     * \param ptr The pointer to the buffer.
+     * \param total_sz The size of the buffer.
+     */
+    bool matches_response(const uint8_t *ptr, uint32_t total_sz) const;
+    
     /**
      * \sa PDU::clone
      */

src/ip.cpp

@@ -432,7 +432,7 @@ bool IP::matches_response(const uint8_t *ptr, uint32_t total_sz) const {
     // checks for broadcast addr
     if((_ip.saddr == ip_ptr->daddr && (_ip.daddr == ip_ptr->saddr || dst_addr().is_broadcast())) ||
         (dst_addr().is_broadcast() && _ip.saddr == 0)) {
-        uint32_t sz = std::min<uint32_t>(_ip.ihl * sizeof(uint32_t), total_sz);
+        uint32_t sz = std::min<uint32_t>(header_size(), total_sz);
         return inner_pdu() ? inner_pdu()->matches_response(ptr + sz, total_sz - sz) : true;
     }
     return false;

src/loopback.cpp

@@ -93,8 +93,7 @@ uint32_t Loopback::header_size() const {
     return sizeof(_family);
 }
 
-void Loopback::write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *) 
-{
+void Loopback::write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *) {
     #ifdef TINS_DEBUG
     assert(total_sz >= sizeof(_family));
     #endif
@@ -106,6 +105,19 @@ void Loopback::write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU
     *reinterpret_cast<uint32_t*>(buffer) = _family;
     #endif // WIN32
 }
+
+bool Loopback::matches_response(const uint8_t *ptr, uint32_t total_sz) const {
+    if(total_sz < sizeof(_family)) {
+        return false;
+    }
+    // If there's an inner_pdu, check if the inner pdu matches.
+    // Otherwise, just check this loopback family.
+    
+    return inner_pdu() ? 
+        inner_pdu()->matches_response(ptr + sizeof(_family), total_sz - sizeof(_family)) :
+        (_family == *reinterpret_cast<const uint32_t*>(ptr));
+}
+
 #ifdef BSD
 void Loopback::send(PacketSender &sender, const NetworkInterface &iface) {
     if(!iface)

tests/src/CMakeLists.txt

@@ -1,5 +1,5 @@
 # Use libtins' include directories + test include directories
-INCLUDE_DIRECTORIES(${PROJECT_SOURCE_DIR}/include/ ../include/)
+INCLUDE_DIRECTORIES(${PROJECT_SOURCE_DIR}/include/tins/ ../include/)
 
 # Find pthread library
 FIND_PACKAGE(Threads REQUIRED)
@@ -52,6 +52,7 @@ ADD_CUSTOM_TARGET(
     IPv6Test
     IPv6AddressTest
     LLCTest
+    LoopbackTest
     MatchesResponseTest
     NetworkInterfaceTest
     OfflinePacketFilterTest
@@ -92,6 +93,7 @@ ADD_EXECUTABLE(IPSecTest EXCLUDE_FROM_ALL ipsec.cpp)
 ADD_EXECUTABLE(IPv6Test EXCLUDE_FROM_ALL ipv6.cpp)
 ADD_EXECUTABLE(IPv6AddressTest EXCLUDE_FROM_ALL ipv6address.cpp)
 ADD_EXECUTABLE(LLCTest EXCLUDE_FROM_ALL llc.cpp)
+ADD_EXECUTABLE(LoopbackTest EXCLUDE_FROM_ALL loopback.cpp)
 ADD_EXECUTABLE(MatchesResponseTest EXCLUDE_FROM_ALL matches_response.cpp)
 ADD_EXECUTABLE(NetworkInterfaceTest EXCLUDE_FROM_ALL network_interface.cpp)
 ADD_EXECUTABLE(OfflinePacketFilterTest EXCLUDE_FROM_ALL offline_packet_filter.cpp)
@@ -170,6 +172,7 @@ ADD_TEST(IPSec IPSecTest)
 ADD_TEST(IPv6 IPv6Test)
 ADD_TEST(IPv6Address IPv6AddressTest)
 ADD_TEST(LLC LLCTest)
+ADD_TEST(Loopback LoopbackTest)
 ADD_TEST(MatchesResponse MatchesResponseTest)
 ADD_TEST(NetworkInterface NetworkInterfaceTest)
 ADD_TEST(OfflinePacketFilter OfflinePacketFilterTest)

tests/src/loopback.cpp

@@ -0,0 +1,35 @@
+#include <gtest/gtest.h>
+#include <cstring>
+#include <string>
+#include <stdint.h>
+#include "macros.h"
+#ifndef WIN32
+    #include <sys/socket.h>
+    #ifdef BSD
+        #include <net/if_dl.h>
+        #include <netinet/in.h>
+        #include <net/ethernet.h>
+    #endif
+#endif
+#include "loopback.h"
+#include "ip.h"
+#include "tcp.h"
+
+using namespace std;
+using namespace Tins;
+
+class LoopbackTest : public testing::Test {
+public:
+    
+};
+
+#ifndef WIN32
+TEST_F(LoopbackTest, MatchesResponse) {
+    Loopback loop1 = Loopback() / IP("192.168.0.1", "192.168.0.2") / TCP(22, 21);
+    loop1.family(PF_INET);
+    Loopback loop2 = Loopback() / IP("192.168.0.2", "192.168.0.1") / TCP(21, 22);
+    loop2.family(PF_INET);
+    PDU::serialization_type buffer = loop2.serialize();
+    EXPECT_TRUE(loop1.matches_response(&buffer[0], buffer.size()));
+}
+#endif // WIN32