1 files changed, 85 insertions, 0 deletions
diff --git a/lib/scanner.py b/lib/scanner.py
new file mode 100644
index 0000000..f78e4f6
--- /dev/null
+++ b/lib/scanner.py
@@ -0,0 +1,85 @@
+import struct
+import socket
+import threading
+import queue
+import logging
+
+from enum import Enum, auto
+
+logger = logging.getLogger(__name__)
+
+
+class PortState(Enum):
+    OPEN = auto()
+    CLOSED = auto()
+    FILTERED = auto()
+
+
+class TCPScanner:
+    def __init__(self, host, ports, timeout=5):
+        self.host = host
+        self.ports = ports
+        self.timeout = timeout
+        self.results = []
+        self.q = queue.SimpleQueue()
+        self.failed = False
+
+    def scan(self, num_threads=5):
+        for port in self.ports:
+            self.q.put(port)
+
+        threads = []
+        for i in range(num_threads):
+            t = threading.Thread(target=self.run)
+            t.start()
+            threads.append(t)
+
+        for t in threads:
+            t.join()
+
+    def run(self):
+        while True:
+            if self.failed:
+                break
+
+            try:
+                port = self.q.get(block=False)
+            except queue.Empty:
+                break
+
+            try:
+                self._scan(port)
+            except Exception as e:
+                logger.exception(e)
+                self.failed = True
+                break
+
+    def _scan(self, port):
+        try:
+            conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+            conn.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER, struct.pack("ii", 1, 0))
+            conn.settimeout(self.timeout)
+
+            ret = conn.connect_ex((self.host, port))
+
+            # DATA RECEIVED - SYN ACK
+            if ret == 0:
+                logger.debug('%s:%d - tcp open (SYN-ACK packet)' % (self.host, port))
+                self.results.append((port, PortState.OPEN))
+
+            # RST RECEIVED - PORT CLOSED
+            elif ret == 111:
+                logger.debug('%s:%d - tcp closed (RST packet)' % (self.host, port))
+                self.results.append((port, PortState.CLOSED))
+
+            # ERR CODE 11 - TIMEOUT
+            elif ret == 11:
+                self.results.append((port, PortState.FILTERED))
+
+            else:
+                logger.debug('%s:%d - code %d' % (self.host, port, ret))
+
+            conn.close()
+
+        except socket.timeout:
+            self.results.append((port, PortState.FILTERED))
+\ No newline at end of file