Added GTPU PDU Session header parsing

lib/include/srsran/upper/gtpu.h

@@ -58,8 +58,11 @@ namespace srsran {
 #define GTPU_MSG_END_MARKER 254
 #define GTPU_MSG_DATA_PDU 255
 
+#define GTPU_EXT_NO_MORE_EXTENSION_HEADERS 0x00
 #define GTPU_EXT_HEADER_PDCP_PDU_NUMBER 0b11000000
+#define GTPU_EXT_HEADER_PDU_SESSION_CONTAINER 0x85
 
+#define GTPU_EXT_HEADER_PDU_SESSION_CONTAINER_LEN 4
 struct gtpu_header_t {
   uint8_t              flags             = 0;
   uint8_t              message_type      = 0;

lib/src/gtpu/gtpu.cc

@@ -112,7 +112,9 @@ bool gtpu_read_ext_header(srsran::byte_buffer_t* pdu,
     return true;
   }
 
-  if (header->next_ext_hdr_type == GTPU_EXT_HEADER_PDCP_PDU_NUMBER) {
+  // TODO: Iterate over next headers until no more extension headers
+  switch (header->next_ext_hdr_type) {
+    case GTPU_EXT_HEADER_PDCP_PDU_NUMBER:
       pdu->msg += HEADER_PDCP_PDU_NUMBER_SIZE;
       pdu->N_bytes -= HEADER_PDCP_PDU_NUMBER_SIZE;
       header->ext_buffer.resize(HEADER_PDCP_PDU_NUMBER_SIZE);
@@ -120,7 +122,14 @@ bool gtpu_read_ext_header(srsran::byte_buffer_t* pdu,
         header->ext_buffer[i] = **ptr;
         (*ptr)++;
       }
-  } else {
+      break;
+    case GTPU_EXT_HEADER_PDU_SESSION_CONTAINER:
+      pdu->msg += GTPU_EXT_HEADER_PDU_SESSION_CONTAINER_LEN;
+      pdu->N_bytes -= GTPU_EXT_HEADER_PDU_SESSION_CONTAINER_LEN;
+      logger.warning("skip parsing of GTPU_EXT_HEADER_PDU_SESSION_CONTAINER");
+      // TODO: Save Header Extension
+      break;
+    default:
       logger.error("gtpu_read_header - Unhandled GTP-U Extension Header Type: 0x%x", header->next_ext_hdr_type);
       return false;
   }