anonymizer: option to skip SRC_IP (-S)/DST_IP (-D)

Two optional parameters were added to skip anonymization of
SRC_IP (option -S) or DST_IP (option -D).

Example to leave SRC_IP without any modification:
/usr/bin/nemea/anonymizer -i u:input,u:output -S

Example to leave both SRC_IP and DST_IP without any modification:
/usr/bin/nemea/anonymizer -i u:input,u:output -S -D

anonymizer/README

@@ -28,5 +28,7 @@ Anonymization key: 32 characters long string or 32B sized hex string starting wi
 
 Parameters: -k KEY     Specify anonymization key.
             -f FILE    Specify file containg anonymization key.
+            -S         Disable anonymization of SRC_IP.
+            -D         Disable anonymization of DST_IP.
             -M         Use MurmurHash3 instead of Rijndael cipher.
             -d         Switch to de-anonymization mode, i.e. do reverse transofmration of the addresses.

anonymizer/anonymizer.c

@@ -6,10 +6,11 @@
  * \author Tomas Jansky <[email protected]>
  * \author Martin Zadnik <[email protected]>
  * \author Tomas Cejka <[email protected]>
+ * \date 2024
  * \date 2017
  */
 /*
- * Copyright (C) 2013-2018 CESNET
+ * Copyright (C) 2013-2024 CESNET
  *
  * LICENSE TERMS
  *
@@ -71,10 +72,15 @@ trap_module_info_t *module_info = NULL;
    PARAM('k', "key", "Specify secret key, the key must be 32 characters long string or 32B sized hex string starting with 0x", required_argument, "string") \
    PARAM('f', "file", "Specify file containing secret key, the key must be 32 characters long string or 32B sized hex string starting with 0x", required_argument, "string") \
    PARAM('M', "murmur", "Use MurmurHash3 instead of Rijndael cipher.", no_argument, "none") \
+   PARAM('S', "srcip", "Disable anonymization of SRC_IP.", no_argument, "none") \
+   PARAM('D', "dstip", "Disable anonymization of DST_IP.", no_argument, "none") \
    PARAM('d', "de-anonym", "Switch to de-anonymization mode.", no_argument, "none")
 
 static int stop = 0;
 
+static int disable_src_ip = 0;
+static int disable_dst_ip = 0;
+
 TRAP_DEFAULT_SIGNAL_HANDLER(stop = 1);
 
 const char *anon_field_names[] = {"SRC_IP", "DST_IP", "SIP_CALLED_PARTY", "SIP_CALLING_PARTY", "SIP_CALL_ID", "SIP_REQUEST_URI", "SIP_VIA"};
@@ -331,6 +337,13 @@ int set_fields_present(ur_template_t *tmplt)
    int j = 0;
 
    for (i = 0; i < ANON_FIELDS_COUNT; i++) {
+      // check skip flags for src_ip and dst_ip (-S / -D) and skip these fields
+      if (disable_src_ip == 1 && strncmp(anon_field_names[i], "SRC_IP", 7) == 0) {
+         continue;
+      }
+      if (disable_dst_ip == 1 && strncmp(anon_field_names[i], "DST_IP", 7) == 0) {
+         continue;
+      }
       anon_fields[j] = ur_get_id_by_name(anon_field_names[i]);
       if (anon_fields[j] != UR_E_INVALID_NAME && ur_is_present(tmplt, anon_fields[j])) {
          j++;
@@ -415,6 +428,12 @@ int main(int argc, char **argv)
       case 'd':
          mode = DEANONYMIZATION;
          break;
+      case 'S':
+         disable_src_ip = 1;
+         break;
+      case 'D':
+         disable_dst_ip = 1;
+         break;
       default:
          fprintf(stderr, "Invalid arguments.\n");
          ret = 1;