libzypp  17.10.1
CheckAccessDeleted.cc
Go to the documentation of this file.
1 /*---------------------------------------------------------------------\
2 | ____ _ __ __ ___ |
3 | |__ / \ / / . \ . \ |
4 | / / \ V /| _/ _/ |
5 | / /__ | | | | | | |
6 | /_____||_| |_| |_| |
7 | |
8 \---------------------------------------------------------------------*/
12 #include <iostream>
13 #include <fstream>
14 #include <unordered_set>
15 #include <iterator>
16 #include <stdio.h>
17 #include "zypp/base/LogTools.h"
18 #include "zypp/base/String.h"
19 #include "zypp/base/Gettext.h"
20 #include "zypp/base/Exception.h"
21 
22 #include "zypp/PathInfo.h"
23 #include "zypp/ExternalProgram.h"
24 #include "zypp/base/Regex.h"
25 #include "zypp/base/IOStream.h"
26 #include "zypp/base/InputStream.h"
28 
30 
31 using std::endl;
32 
33 #undef ZYPP_BASE_LOGGER_LOGGROUP
34 #define ZYPP_BASE_LOGGER_LOGGROUP "zypp::misc"
35 
37 namespace zypp
38 {
39 
41  namespace
42  {
43  //
44  // lsof output lines are a sequence of NUL terminated fields,
45  // where the 1st char determines the fields type.
46  //
47  // (pcuL) pid command userid loginname
48  // (ftkn).filedescriptor type linkcount filename
49  //
51 
53  typedef std::pair<std::string,std::unordered_set<std::string>> CacheEntry;
54 
61  struct FilterRunsInLXC
62  {
63  bool operator()( pid_t pid_r ) const
64  { return( nsIno( pid_r, "pid" ) != pidNS ); }
65 
66  FilterRunsInLXC()
67  : pidNS( nsIno( "self", "pid" ) )
68  {}
69 
70  static inline ino_t nsIno( const std::string & pid_r, const std::string & ns_r )
71  { return PathInfo("/proc/"+pid_r+"/ns/"+ns_r).ino(); }
72 
73  static inline ino_t nsIno( pid_t pid_r, const std::string & ns_r )
74  { return nsIno( asString(pid_r), ns_r ); }
75 
76  ino_t pidNS;
77  };
78 
84  bool lsofNoOptKi()
85  {
86  using target::rpm::librpmDb;
87  // RpmDb access is blocked while the Target is not initialized.
88  // Launching the Target just for this query would be an overkill.
89  struct TmpUnblock {
90  TmpUnblock()
91  : _wasBlocked( librpmDb::isBlocked() )
92  { if ( _wasBlocked ) librpmDb::unblockAccess(); }
93  ~TmpUnblock()
94  { if ( _wasBlocked ) librpmDb::blockAccess(); }
95  private:
96  bool _wasBlocked;
97  } tmpUnblock;
98 
99  librpmDb::db_const_iterator it;
100  return( it.findPackage( "lsof" ) && it->tag_edition() < Edition("4.90") && !it->tag_provides().count( Capability("backported-option-Ki") ) );
101  }
102 
103  } //namespace
105 
107  {
108  public:
110 
111  bool addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap = nullptr );
112  void addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap = nullptr );
113 
114  std::map<pid_t,CacheEntry> filterInput( externalprogram::ExternalDataSource &source );
115  CheckAccessDeleted::size_type createProcInfo( const std::map<pid_t,CacheEntry> &in );
116 
117  std::vector<CheckAccessDeleted::ProcInfo> _data;
118  bool _fromLsofFileMode = false; // Set if we currently process data from a debug file
119  bool _verbose = false;
120 
121  std::map<pid_t,std::vector<std::string>> debugMap; //will contain all used lsof files after filtering
123  };
124 
126  {
127  Impl *myClone = new Impl( *this );
128  return myClone;
129  }
130 
135  inline bool CheckAccessDeleted::Impl::addDataIf( const CacheEntry & cache_r, std::vector<std::string> *debMap )
136  {
137  const auto & filelist( cache_r.second );
138 
139  if ( filelist.empty() )
140  return false;
141 
142  // at least one file access so keep it:
143  _data.push_back( CheckAccessDeleted::ProcInfo() );
144  CheckAccessDeleted::ProcInfo & pinfo( _data.back() );
145  pinfo.files.insert( pinfo.files.begin(), filelist.begin(), filelist.end() );
146 
147  const std::string & pline( cache_r.first );
148  std::string commandname; // pinfo.command if still needed...
149  std::ostringstream pLineStr; //rewrite the first line in debug cache
150  for_( ch, pline.begin(), pline.end() )
151  {
152  switch ( *ch )
153  {
154  case 'p':
155  pinfo.pid = &*(ch+1);
156  if ( debMap )
157  pLineStr <<&*(ch)<<'\0';
158  break;
159  case 'R':
160  pinfo.ppid = &*(ch+1);
161  if ( debMap )
162  pLineStr <<&*(ch)<<'\0';
163  break;
164  case 'u':
165  pinfo.puid = &*(ch+1);
166  if ( debMap )
167  pLineStr <<&*(ch)<<'\0';
168  break;
169  case 'L':
170  pinfo.login = &*(ch+1);
171  if ( debMap )
172  pLineStr <<&*(ch)<<'\0';
173  break;
174  case 'c':
175  if ( pinfo.command.empty() ) {
176  commandname = &*(ch+1);
177  // the lsof command name might be truncated, so we prefer /proc/<pid>/exe
178  if (!_fromLsofFileMode)
179  pinfo.command = filesystem::readlink( Pathname("/proc")/pinfo.pid/"exe" ).basename();
180  if ( pinfo.command.empty() )
181  pinfo.command = std::move(commandname);
182  if ( debMap )
183  pLineStr <<'c'<<pinfo.command<<'\0';
184  }
185  break;
186  }
187  if ( *ch == '\n' ) break; // end of data
188  do { ++ch; } while ( *ch != '\0' ); // skip to next field
189  }
190 
191  //replace the data in the debug cache as well
192  if ( debMap ) {
193  pLineStr<<endl;
194  debMap->front() = pLineStr.str();
195  }
196 
197  //entry was added
198  return true;
199  }
200 
201 
207  inline void CheckAccessDeleted::Impl::addCacheIf( CacheEntry & cache_r, const std::string & line_r, std::vector<std::string> *debMap )
208  {
209  const char * f = 0;
210  const char * t = 0;
211  const char * n = 0;
212 
213  for_( ch, line_r.c_str(), ch+line_r.size() )
214  {
215  switch ( *ch )
216  {
217  case 'k':
218  if ( *(ch+1) != '0' ) // skip non-zero link counts
219  return;
220  break;
221  case 'f':
222  f = ch+1;
223  break;
224  case 't':
225  t = ch+1;
226  break;
227  case 'n':
228  n = ch+1;
229  break;
230  }
231  if ( *ch == '\n' ) break; // end of data
232  do { ++ch; } while ( *ch != '\0' ); // skip to next field
233  }
234 
235  if ( !t || !f || !n )
236  return; // wrong filedescriptor/type/name
237 
238  if ( !( ( *t == 'R' && *(t+1) == 'E' && *(t+2) == 'G' && *(t+3) == '\0' )
239  || ( *t == 'D' && *(t+1) == 'E' && *(t+2) == 'L' && *(t+3) == '\0' ) ) )
240  return; // wrong type
241 
242  if ( !( ( *f == 'm' && *(f+1) == 'e' && *(f+2) == 'm' && *(f+3) == '\0' )
243  || ( *f == 't' && *(f+1) == 'x' && *(f+2) == 't' && *(f+3) == '\0' )
244  || ( *f == 'D' && *(f+1) == 'E' && *(f+2) == 'L' && *(f+3) == '\0' )
245  || ( *f == 'l' && *(f+1) == 't' && *(f+2) == 'x' && *(f+3) == '\0' ) ) )
246  return; // wrong filedescriptor type
247 
248  if ( str::contains( n, "(stat: Permission denied)" ) )
249  return; // Avoid reporting false positive due to insufficient permission.
250 
251  if ( ! _verbose )
252  {
253  if ( ! ( str::contains( n, "/lib" ) || str::contains( n, "bin/" ) ) )
254  return; // Try to avoid reporting false positive unless verbose.
255  }
256 
257  if ( *f == 'm' || *f == 'D' ) // skip some wellknown nonlibrary memorymapped files
258  {
259  static const char * black[] = {
260  "/SYSV"
261  , "/var/"
262  , "/dev/"
263  , "/tmp/"
264  , "/proc/"
265  };
266  for_( it, arrayBegin( black ), arrayEnd( black ) )
267  {
268  if ( str::hasPrefix( n, *it ) )
269  return;
270  }
271  }
272  // Add if no duplicate
273  if ( debMap && cache_r.second.find(n) == cache_r.second.end() ) {
274  debMap->push_back(line_r);
275  }
276  cache_r.second.insert( n );
277  }
278 
280  : _pimpl(new Impl)
281  {
282  if ( doCheck_r ) check();
283  }
284 
285  CheckAccessDeleted::size_type CheckAccessDeleted::check( const Pathname &lsofOutput_r, bool verbose_r )
286  {
287  _pimpl->_verbose = verbose_r;
288  _pimpl->_fromLsofFileMode = true;
289 
290  FILE *inFile = fopen( lsofOutput_r.c_str(), "r" );
291  if ( !inFile ) {
292  ZYPP_THROW( Exception( str::Format("Opening input file %1% failed.") % lsofOutput_r.c_str() ) );
293  }
294 
295  //inFile is closed by ExternalDataSource
296  externalprogram::ExternalDataSource inSource( inFile, nullptr );
297  auto cache = _pimpl->filterInput( inSource );
298  return _pimpl->createProcInfo( cache );
299  }
300 
302  {
303  // cachemap: PID => (deleted files)
304  // NOTE: omit PIDs running in a (lxc/docker) container
305  std::map<pid_t,CacheEntry> cachemap;
306 
307  bool debugEnabled = !_debugFile.empty();
308 
309  pid_t cachepid = 0;
310  FilterRunsInLXC runsInLXC;
311  for( std::string line = source.receiveLine(); ! line.empty(); line = source.receiveLine() )
312  {
313  // NOTE: line contains '\0' separeated fields!
314  if ( line[0] == 'p' )
315  {
316  str::strtonum( line.c_str()+1, cachepid ); // line is "p<PID>\0...."
317  if ( _fromLsofFileMode || !runsInLXC( cachepid ) ) {
318  if ( debugEnabled ) {
319  auto &pidMad = debugMap[cachepid];
320  if ( pidMad.empty() )
321  debugMap[cachepid].push_back( line );
322  else
323  debugMap[cachepid].front() = line;
324  }
325  cachemap[cachepid].first.swap( line );
326  } else {
327  cachepid = 0; // ignore this pid
328  }
329  }
330  else if ( cachepid )
331  {
332  auto &dbgMap = debugMap[cachepid];
333  addCacheIf( cachemap[cachepid], line, debugEnabled ? &dbgMap : nullptr);
334  }
335  }
336  return cachemap;
337  }
338 
340  {
341  static const char* argv[] = { "lsof", "-n", "-FpcuLRftkn0", "-K", "i", NULL };
342  if ( lsofNoOptKi() )
343  argv[3] = NULL;
344 
345  _pimpl->_verbose = verbose_r;
346  _pimpl->_fromLsofFileMode = false;
347 
349  std::map<pid_t,CacheEntry> cachemap = _pimpl->filterInput( prog );
350 
351  int ret = prog.close();
352  if ( ret != 0 )
353  {
354  if ( ret == 129 )
355  {
356  ZYPP_THROW( Exception(_("Please install package 'lsof' first.") ) );
357  }
358  Exception err( str::Format("Executing 'lsof' failed (%1%).") % ret );
359  err.remember( prog.execError() );
360  ZYPP_THROW( err );
361  }
362 
363  return _pimpl->createProcInfo( cachemap );
364  }
365 
367  {
368  std::ofstream debugFileOut;
369  bool debugEnabled = false;
370  if ( !_debugFile.empty() ) {
371  debugFileOut.open( _debugFile.c_str() );
372  debugEnabled = debugFileOut.is_open();
373 
374  if ( !debugEnabled ) {
375  ERR<<"Unable to open debug file: "<<_debugFile<<endl;
376  }
377  }
378 
379  _data.clear();
380  for ( const auto &cached : in )
381  {
382  if (!debugEnabled)
383  addDataIf( cached.second);
384  else {
385  std::vector<std::string> *mapPtr = nullptr;
386 
387  auto dbgInfo = debugMap.find(cached.first);
388  if ( dbgInfo != debugMap.end() )
389  mapPtr = &(dbgInfo->second);
390 
391  if( !addDataIf( cached.second, mapPtr ) )
392  continue;
393 
394  for ( const std::string &dbgLine: dbgInfo->second ) {
395  debugFileOut.write( dbgLine.c_str(), dbgLine.length() );
396  }
397  }
398  }
399  return _data.size();
400  }
401 
403  {
404  return _pimpl->_data.empty();
405  }
406 
408  {
409  return _pimpl->_data.size();
410  }
411 
413  {
414  return _pimpl->_data.begin();
415  }
416 
418  {
419  return _pimpl->_data.end();
420  }
421 
423  {
424  _pimpl->_debugFile = filename_r;
425  }
426 
427  std::string CheckAccessDeleted::findService( pid_t pid_r )
428  {
429  ProcInfo p;
430  p.pid = str::numstring( pid_r );
431  return p.service();
432  }
433 
435  {
436  static const str::regex rx( "[0-9]+:name=systemd:/system.slice/(.*/)?(.*).service$" );
437  str::smatch what;
438  std::string ret;
439  iostr::simpleParseFile( InputStream( Pathname("/proc")/pid/"cgroup" ),
440  [&]( int num_r, std::string line_r )->bool
441  {
442  if ( str::regex_match( line_r, what, rx ) )
443  {
444  ret = what[2];
445  return false; // stop after match
446  }
447  return true;
448  } );
449  return ret;
450  }
451 
452  /******************************************************************
453  **
454  ** FUNCTION NAME : operator<<
455  ** FUNCTION TYPE : std::ostream &
456  */
457  std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted & obj )
458  {
459  return dumpRange( str << "CheckAccessDeleted ",
460  obj.begin(),
461  obj.end() );
462  }
463 
464  /******************************************************************
465  **
466  ** FUNCTION NAME : operator<<
467  ** FUNCTION TYPE : std::ostream &
468  */
469  std::ostream & operator<<( std::ostream & str, const CheckAccessDeleted::ProcInfo & obj )
470  {
471  if ( obj.pid.empty() )
472  return str << "<NoProc>";
473 
474  return dumpRangeLine( str << obj.command
475  << '<' << obj.pid
476  << '|' << obj.ppid
477  << '|' << obj.puid
478  << '|' << obj.login
479  << '>',
480  obj.files.begin(),
481  obj.files.end() );
482  }
483 
485 } // namespace zypp
bool addDataIf(const CacheEntry &cache_r, std::vector< std::string > *debMap=nullptr)
Add cache to data if the process is accessing deleted files.
Interface to gettext.
Data about one running process accessing deleted files.
Bidirectional stream to external data.
bool contains(const C_Str &str_r, const C_Str &val_r)
Locate substring case sensitive.
Definition: String.h:957
std::map< pid_t, CacheEntry > filterInput(externalprogram::ExternalDataSource &source)
std::string asString(const DefaultIntegral< Tp, TInitial > &obj)
#define ZYPP_THROW(EXCPT)
Drops a logline and throws the Exception.
Definition: Exception.h:392
Regular expression.
Definition: Regex.h:86
std::map< pid_t, std::vector< std::string > > debugMap
int readlink(const Pathname &symlink_r, Pathname &target_r)
Like &#39;readlink&#39;.
Definition: PathInfo.cc:877
void setDebugOutputFile(const Pathname &filename_r)
Writes all filtered process entries that make it into the final set into a file specified by filename...
std::ostream & dumpRange(std::ostream &str, TIterator begin, TIterator end, const std::string &intro="{", const std::string &pfx="\ ", const std::string &sep="\ ", const std::string &sfx="\, const std::string &extro="}")
Print range defined by iterators (multiline style).
Definition: LogTools.h:91
const char * c_str() const
String representation.
Definition: Pathname.h:109
std::string command
process command name
String related utilities and Regular expression matching.
Helper to create and pass std::istream.
Definition: InputStream.h:56
#define for_(IT, BEG, END)
Convenient for-loops using iterator.
Definition: Easy.h:27
Convenient building of std::string with boost::format.
Definition: String.h:251
std::ostream & operator<<(std::ostream &str, const CheckAccessDeleted &obj)
#define ERR
Definition: Logger.h:81
void remember(const Exception &old_r)
Store an other Exception as history.
Definition: Exception.cc:105
CheckAccessDeleted::Impl * clone() const
bool empty() const
Test for an empty path.
Definition: Pathname.h:113
size_type check(bool verbose_r=false)
Check for running processes which access deleted executables or libraries.
RWCOW_pointer< Impl > _pimpl
const_iterator begin() const
int simpleParseFile(std::istream &str_r, ParseFlags flags_r, function< bool(int, std::string)> consume_r)
Simple lineparser optionally trimming and skipping comments.
Definition: IOStream.cc:124
const std::string & execError() const
Some detail telling why the execution failed, if it failed.
Execute a program and give access to its io An object of this class encapsulates the execution of an ...
std::list< PublicKeyData > _data
Definition: KeyRing.cc:145
std::vector< CheckAccessDeleted::ProcInfo > _data
TInt strtonum(const C_Str &str)
Parsing numbers from string.
Definition: String.h:387
std::string puid
process user ID
const_iterator end() const
#define _(MSG)
Definition: Gettext.h:37
std::string receiveLine()
Read one line from the input stream.
std::string numstring(char n, int w=0)
Definition: String.h:288
CheckAccessDeleted::size_type createProcInfo(const std::map< pid_t, CacheEntry > &in)
int close()
Wait for the progamm to complete.
#define arrayEnd(A)
Definition: Easy.h:42
#define arrayBegin(A)
Simple C-array iterator.
Definition: Easy.h:40
Regular expression match result.
Definition: Regex.h:145
Base class for Exception.
Definition: Exception.h:145
Check for running processes which access deleted executables or libraries.
CheckAccessDeleted(bool doCheck_r=true)
Default ctor performs check immediately.
std::ostream & dumpRangeLine(std::ostream &str, TIterator begin, TIterator end)
Print range defined by iterators (single line style).
Definition: LogTools.h:114
ino_t pidNS
bool regex_match(const std::string &s, smatch &matches, const regex &regex)
regex ZYPP_STR_REGEX regex ZYPP_STR_REGEX
Definition: Regex.h:70
Easy-to use interface to the ZYPP dependency resolver.
Definition: CodePitfalls.doc:1
bool hasPrefix(const C_Str &str_r, const C_Str &prefix_r)
Return whether str_r has prefix prefix_r.
Definition: String.h:1020
std::vector< ProcInfo >::const_iterator const_iterator
std::string login
process login name
void addCacheIf(CacheEntry &cache_r, const std::string &line_r, std::vector< std::string > *debMap=nullptr)
Add file to cache if it refers to a deleted executable or library file:
std::vector< std::string > files
list of deleted executables or libraries accessed
std::string ppid
parent process ID
std::string service() const
Guess if command was started by a systemd service script.
static std::string findService(pid_t pid_r)
Guess if pid was started by a systemd service script.