Merge pull request #211 from art3x/issue-208-fix-shell-detection

Issues 208 (stat output verification) and 210 (shell detection) fixes

CHANGELOG.md

@@ -21,6 +21,9 @@ and simply didn't have the time to go back and retroactively create one.
 - Forced `Stream.RAW` for all GTFOBins interaction ([#195](https://github.com/calebstewart/pwncat/issues/195)).
 - Added custom `which` implementation for linux when `which` is not available ([#193](https://github.com/calebstewart/pwncat/issues/193)).
 - Correctly handle `--listen` argument ([#201](https://github.com/calebstewart/pwncat/issues/201))
+- Added additional check for stat time of file birth field (#208)
+- Removed shell compare with ["nologin", "false", "sync", "git-shell"] (#210)
+- Added shell compare with not in ["bash", "zsh", "ksh", "fish"] (#210)
 ### Added
 - Added alternatives to `bash` to be used during _shell upgrade_ for a _better shell_
 - Added a warning message when a `KeyboardInterrupt` is caught

pwncat/platform/linux.py

@@ -616,19 +616,14 @@ class Linux(Platform):
         if self.shell == "" or self.shell is None:
             self.shell = "/bin/sh"
 
-        # This doesn't make sense, but happened for some people (see issue #116)
-        if os.path.basename(self.shell) in ["nologin", "false", "sync", "git-shell"]:
-            self.shell = "/bin/sh"
-            self.channel.sendline(b" export SHELL=/bin/sh")
-
         if self._do_which("which") is None:
             self._do_which = self._do_custom_which
 
-        if os.path.basename(self.shell) in ["sh", "dash"]:
+        better_shells = ["bash", "zsh", "ksh", "fish"]
+        if os.path.basename(self.shell) not in better_shells:
             # Try to find a better shell
             # a custom `pwncat shell prompt` may not be available for all shells
             # see `self.PROMPTS`
-            better_shells = ["bash", "zsh", "ksh", "fish"]
 
             for better_shell in better_shells:
                 shell = self._do_which(better_shell)
@@ -1743,6 +1738,10 @@ class Linux(Platform):
             if fields[i] == "?":
                 fields[i] = "0"
 
+        # Fix stat output issues in some enviroments
+        if fields[1] == "W":
+            fields[1] = "0"
+
         stat = os.stat_result(
             tuple(
                 [