| 1 | #!/usr/bin/python | 
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| 2 | # -*- coding: utf-8 -*- | 
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| 3 |  | 
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| 4 | # better-mousetrapfs: Filesystem that logs and kills any accessors | 
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| 5 | # version 1.0, released 2010-03-31 | 
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| 6 | # Copyright © 2010 Anders Kaseorg <andersk@mit.edu> | 
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| 7 | # | 
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| 8 | # Permission is hereby granted, free of charge, to any person | 
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| 9 | # obtaining a copy of this software and associated documentation files | 
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| 10 | # (the “Software”), to deal in the Software without restriction, | 
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| 11 | # including without limitation the rights to use, copy, modify, merge, | 
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| 12 | # publish, distribute, sublicense, and/or sell copies of the Software, | 
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| 13 | # and to permit persons to whom the Software is furnished to do so, | 
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| 14 | # subject to the following conditions: | 
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| 15 | # | 
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| 16 | # The above copyright notice and this permission notice shall be | 
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| 17 | # included in all copies or substantial portions of the Software. | 
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| 18 | # | 
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| 19 | # THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, | 
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| 20 | # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | 
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| 21 | # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | 
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| 22 | # NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS | 
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| 23 | # BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN | 
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| 24 | # ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | 
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| 25 | # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | 
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| 26 | # SOFTWARE. | 
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| 27 |  | 
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| 28 | import errno | 
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| 29 | import fuse | 
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| 30 | import grp | 
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| 31 | import os | 
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| 32 | import pwd | 
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| 33 | import signal | 
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| 34 | import stat | 
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| 35 | import syslog | 
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| 36 |  | 
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| 37 | fuse.fuse_python_api = (0, 2) | 
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| 38 |  | 
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| 39 | class BetterMousetrapFS(fuse.Fuse): | 
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| 40 | def __init__(self, *args, **kwargs): | 
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| 41 | syslog.openlog('better-mousetrapfs') | 
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| 42 | fuse.Fuse.__init__(self, *args, **kwargs) | 
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| 43 |  | 
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| 44 | def getattr(self, path): | 
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| 45 | if path == '/': | 
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| 46 | return fuse.Stat(st_mode = stat.S_IFDIR | 0755, st_nlink = 2) | 
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| 47 | else: | 
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| 48 | return -errno.EACCES | 
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| 49 |  | 
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| 50 | def opendir(self, path): | 
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| 51 | self.spring(fuse.FuseGetContext()) | 
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| 52 | return -errno.EACCES | 
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| 53 |  | 
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| 54 | def spring(self, context): | 
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| 55 | pid = context['pid'] | 
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| 56 | uid = context['uid'] | 
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| 57 | gid = context['gid'] | 
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| 58 | try: | 
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| 59 | user = '%d %r' % (uid, pwd.getpwuid(uid).pw_name) | 
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| 60 | except KeyError: | 
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| 61 | user = '%d' % uid | 
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| 62 | try: | 
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| 63 | group = '%d %r' % (gid, grp.getgrgid(gid).gr_name) | 
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| 64 | except KeyError: | 
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| 65 | group = '%d' % gid | 
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| 66 | cmdline = open('/proc/%d/cmdline' % pid).read().split('\0')[:-1] | 
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| 67 | exe = os.readlink('/proc/%d/exe' % pid) | 
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| 68 | status = dict(tuple(v.strip() for v in l.split(':', 1)) | 
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| 69 | for l in open('/proc/%d/status' % pid).readlines()) | 
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| 70 | cwd = os.readlink('/proc/%d/cwd' % pid) | 
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| 71 |  | 
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| 72 | syslog.syslog( | 
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| 73 | syslog.LOG_WARNING | 80, # 80 = LOG_AUTHPRIV | 
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| 74 | 'mousetrap caught process %d, uid=%s, gid=%s, exe=%r, cmdline=%r, cwd=%r' % | 
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| 75 | (pid, user, group, exe, cmdline, cwd)) | 
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| 76 |  | 
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| 77 | try: | 
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| 78 | nonlocal_gid = grp.getgrnam('nss-nonlocal-users').gr_gid | 
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| 79 | except KeyError: | 
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| 80 | nonlocal_gid = None | 
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| 81 | if str(nonlocal_gid) in status['Groups'].split(): | 
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| 82 | os.kill(pid, signal.SIGKILL) | 
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| 83 | pass | 
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| 84 |  | 
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| 85 | if __name__ == '__main__': | 
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| 86 | fs = BetterMousetrapFS() | 
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| 87 | fs.parse(errex=1) | 
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| 88 | fs.fuse_args.add('allow_other') | 
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| 89 | fs.fuse_args.add('ro') | 
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| 90 | fs.main() | 
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