Wc command (#1038)

* wc command

src/cowrie/commands/__init__.py

@@ -34,6 +34,7 @@ __all__ = [
     'tar',
     'uname',
     'ulimit',
+    'wc',
     'wget',
     'which',
     'perl',

src/cowrie/commands/wc.py

@@ -0,0 +1,101 @@
+# Copyright (c) 2019 Nuno Novais <nuno@noais.me>
+# All rights reserved.
+# All rights given to Cowrie project
+
+"""
+This module contains the wc commnad
+"""
+
+from __future__ import absolute_import, division
+
+import getopt
+
+from twisted.python import log
+
+from cowrie.shell.command import HoneyPotCommand
+
+commands = {}
+
+
+class command_wc(HoneyPotCommand):
+    """
+    wc command
+    """
+
+    def help(self):
+        self.writeBytes(b'Usage: wc [OPTION]... [FILE]...\n')
+        self.writeBytes(b'Print newline, word, and byte counts for each FILE, and a total line if\n')
+        self.writeBytes(b'more than one FILE is specified.  A word is a non-zero-length sequence of\n')
+        self.writeBytes(b'characters delimited by white space.\n')
+        self.writeBytes(b'\n')
+        self.writeBytes(b'With no FILE, or when FILE is -, read standard input.\n')
+        self.writeBytes(b'\n')
+        self.writeBytes(b'The options below may be used to select which counts are printed, always in\n')
+        self.writeBytes(b'the following order: newline, word, character, byte, maximum line length.\n')
+        self.writeBytes(b'\t-c\tprint the byte counts\n')
+        self.writeBytes(b'\t-m\tprint the character counts\n')
+        self.writeBytes(b'\t-l\tprint the newline counts\n')
+        self.writeBytes(b'\t-w\tprint the word counts\n')
+        self.writeBytes(b'\t-h\tdisplay this help and exit\n')
+        self.writeBytes(b'\t-v\toutput version information and exit\n')
+
+    def wc_get_contents(self, filename, optlist):
+        try:
+            contents = self.fs.file_contents(filename)
+            self.wc_application(contents, optlist)
+        except Exception:
+            self.errorWrite("wc: {}: No such file or directory\n".format(filename))
+
+    def wc_application(self, contents, optlist):
+        for opt, arg in optlist:
+            if opt == "-l":
+                contentsplit = contents.split(b'\n')
+                self.write("{}\n".format(len(contentsplit) - 1))
+            elif opt == "-w":
+                contentsplit = contents.split(b' ')
+                self.write("{}\n".format(len(contentsplit) - 1))
+            elif opt == "-m" or opt == "-c":
+                self.write("{}\n".format(len(contents)))
+            else:
+                self.help()
+
+    def start(self):
+        if not self.args:
+            self.exit()
+            return
+
+        if self.args[0] == '>':
+            pass
+        else:
+            try:
+                optlist, args = getopt.getopt(self.args, 'cmlLw')
+            except getopt.GetoptError as err:
+                self.errorWrite("wc: invalid option -- {}\n".format(err.opt))
+                self.help()
+                self.exit()
+                return
+            for opt in optlist:
+                if opt == '-h':
+                    self.help()
+
+        if not self.input_data:
+            files = self.check_arguments('wc', args[1:])
+            for pname in files:
+                self.wc_get_contents(pname, optlist)
+        else:
+            self.wc_application(self.input_data, optlist)
+
+        self.exit()
+
+    def lineReceived(self, line):
+        log.msg(eventid='cowrie.command.input',
+                realm='wc',
+                input=line,
+                format='INPUT (%(realm)s): %(input)s')
+
+    def handle_CTRL_D(self):
+        self.exit()
+
+
+commands['/usr/bin/wc'] = command_wc
+commands['/bin/wc'] = command_wc