Merge pull request #217 from CESNET/fix-wg-ipfix-byte-order

Fix wg ipfix byte order

Author: cejkato2

include/ipfixprobe/utils.hpp

@@ -171,6 +171,11 @@ std::string vec2str(const std::vector<T> &vec) {
    return ss.str();
 }
 
+/**
+ * @brief Copy uint32 in little endian byte order to destination in host byte order
+ */
+void memcpy_le32toh(uint32_t* dest, const uint32_t* src);
+
 }
 
 #endif /* IPXP_UTILS_HPP */

process/wg.cpp

@@ -29,6 +29,8 @@
 #include <iostream>
 #include <cstring>
 
+#include <ipfixprobe/utils.hpp>
+
 #include "wg.hpp"
 
 namespace ipxp {
@@ -145,23 +147,23 @@ bool WGPlugin::parse_wg(const char *data, unsigned int payload_len, bool source_
          // compare the current dst_peer and see if it matches the original source.
          // If not, the flow flush may be needed to create a new flow.
          cmp_peer = source_pkt ? ext->src_peer : ext->dst_peer;
-         memcpy(&cmp_new_peer, (data + 4), sizeof(uint32_t));
+         memcpy_le32toh(&cmp_new_peer, reinterpret_cast<const uint32_t*>(data + 4));
 
          if (cmp_peer != 0 && cmp_peer != cmp_new_peer) {
             flow_flush = true;
             return false;
          }
 
-         memcpy(source_pkt ? &(ext->src_peer) : &(ext->dst_peer), (data + 4), sizeof(uint32_t));
+         memcpy_le32toh(source_pkt ? &(ext->src_peer) : &(ext->dst_peer), reinterpret_cast<const uint32_t*>(data + 4));
          break;
 
       case WG_PACKETTYPE_RESP_TO_INIT:
          if (payload_len != WG_PACKETLEN_RESP_TO_INIT) {
             return false;
          }
 
-         memcpy(&(ext->src_peer), (data + 4), sizeof(uint32_t));
-         memcpy(&(ext->dst_peer), (data + 8), sizeof(uint32_t));
+         memcpy_le32toh(&(ext->src_peer), reinterpret_cast<const uint32_t*>(data + 4));
+         memcpy_le32toh(&(ext->dst_peer), reinterpret_cast<const uint32_t*>(data + 8));
 
          // let's swap for the opposite direction
          if (!source_pkt) {
@@ -174,15 +176,15 @@ bool WGPlugin::parse_wg(const char *data, unsigned int payload_len, bool source_
             return false;
          }
 
-         memcpy(source_pkt ? &(ext->dst_peer) : &(ext->src_peer), (data + 4), sizeof(uint32_t));
+         memcpy_le32toh(source_pkt ? &(ext->dst_peer) : &(ext->src_peer), reinterpret_cast<const uint32_t*>(data + 4));
          break;
 
       case WG_PACKETTYPE_TRANSPORT_DATA:
          if (payload_len < WG_PACKETLEN_MIN_TRANSPORT_DATA) {
             return false;
          }
 
-         memcpy(source_pkt ? &(ext->dst_peer) : &(ext->src_peer), (data + 4), sizeof(uint32_t));
+         memcpy_le32toh(source_pkt ? &(ext->dst_peer) : &(ext->src_peer), reinterpret_cast<const uint32_t*>(data + 4));
          break;
    }
 

process/wg.hpp

@@ -29,6 +29,7 @@
 #ifndef IPXP_PROCESS_WG_HPP
 #define IPXP_PROCESS_WG_HPP
 
+#include <endian.h>
 #include <string>
 #include <sstream>
 
@@ -112,9 +113,11 @@ struct RecordExtWG : public RecordExt {
 
       memcpy(buffer, &possible_wg, sizeof(possible_wg));
       buffer += sizeof(possible_wg);
-      memcpy(buffer, &src_peer, sizeof(src_peer));
+      uint32_t src_peer_be = htobe32(src_peer);
+      memcpy(buffer, &src_peer_be, sizeof(src_peer));
       buffer += sizeof(src_peer);
-      memcpy(buffer, &dst_peer, sizeof(dst_peer));
+      uint32_t dst_peer_be = htobe32(dst_peer);
+      memcpy(buffer, &dst_peer_be, sizeof(dst_peer));
       buffer += sizeof(dst_peer);
 
       return requiredLen;

utils.cpp

@@ -29,6 +29,7 @@
 
 #include <arpa/inet.h>
 #include <cstring>
+#include <endian.h>
 #include <string>
 #include <utility>
 
@@ -138,4 +139,9 @@ uint64_t timeval2usec(const struct timeval& tv)
    return tv.tv_sec * usec_in_sec + tv.tv_usec;
 }
 
+void memcpy_le32toh(uint32_t* dest, const uint32_t* src)
+{
+    *dest = le32toh(*src);
+}
+
 } // namespace ipxp