fix nits

EFForg · Dec 17, 2024 · dd8edfe · dd8edfe
1 parent 2b2ad84
commit dd8edfe
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Showing 2 changed files with 6 additions and 4 deletions.
diff --git a/tools/nasparse.py b/tools/nasparse.py
@@ -24,6 +24,9 @@ def parse_nas_message(buffer, uplink=None):
             parsed = NASLTE.parse_NASLTE_MT(bin)
     else:
         parsed = NASLTE.parse_NASLTE_MT(bin)
+
+    if parsed[0] is None: # Not a NAS Packet 
+        raise parsed[1]
     return parsed[0]
 
 def heur_ue_imsi_sent(msg):

diff --git a/tools/pcap_check.py b/tools/pcap_check.py
@@ -10,13 +10,12 @@ def process_pcap(pcap_path):
     print('Opening {}...'.format(pcap_path))
 
     count = 0
-    for (pkt_data, pkt_metadata,) in RawPcapNgReader(pcap_path):
+    for pkt_data, pkt_metadata in RawPcapNgReader(pcap_path):
         count += 1
         gsmtap_len = pkt_data[UDP_LEN+1]  * 4 # gsmtap header length is stored in the 2nd byte of GSMTAP as a number of 32 bit words
         header_end = gsmtap_len + UDP_LEN #length of UDP/IP header plus GSMTAP header
-        gsmtap_end_idx = (len(pkt_data) - header_end) * -1
 
-        gsmtap_hdr = pkt_data[UDP_LEN:gsmtap_end_idx]
+        gsmtap_hdr = pkt_data[UDP_LEN:header_end]
 
         if gsmtap_hdr[2] != TYPE_LTE_NAS:
             continue
@@ -26,7 +25,7 @@ def process_pcap(pcap_path):
         uplink = (gsmtap_hdr[4] & 0b01000000) >> 6
         buffer = pkt_data[header_end:]
         msg = nasparse.parse_nas_message(buffer, uplink)
-        (triggered, message)= nasparse.heur_ue_imsi_sent(msg)
+        triggered, message = nasparse.heur_ue_imsi_sent(msg)
         if triggered:
             print(f"Frame {count} triggered heuristic: {message}")