pdns/misc.hh

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #pragma once
  23 #include <errno.h>
  24 #include <inttypes.h>
  25 #include <cstring>
  26 #include <cstdio>
  27 #include <regex.h>
  28 #include <limits.h>
  29 #include <type_traits>
  30 #include <boost/algorithm/string.hpp>
  31 #include <boost/multi_index_container.hpp>
  32 #include <boost/multi_index/ordered_index.hpp>
  33 #include <boost/tuple/tuple_comparison.hpp>
  34 #include <boost/multi_index/key_extractors.hpp>
  35 #include <boost/multi_index/sequenced_index.hpp>
  36
  37 using namespace ::boost::multi_index;
  38
  39 #include "dns.hh"
  40 #include <atomic>
  41 #include <sys/time.h>
  42 #include <sys/types.h>
  43 #include <sys/socket.h>
  44 #include <time.h>
  45 #include <syslog.h>
  46 #include <deque>
  47 #include <stdexcept>
  48 #include <string>
  49 #include <ctype.h>
  50 #include <vector>
  51
  52 #include "namespaces.hh"
  53 #include "dnsname.hh"
  54
  55 typedef enum { TSIG_MD5, TSIG_SHA1, TSIG_SHA224, TSIG_SHA256, TSIG_SHA384, TSIG_SHA512, TSIG_GSS } TSIGHashEnum;
  56
  57 string nowTime();
  58 const string unquotify(const string &item);
  59 string humanDuration(time_t passed);
  60 bool stripDomainSuffix(string *qname, const string &domain);
  61 void stripLine(string &line);
  62 string getHostname();
  63 string urlEncode(const string &text);
  64 int waitForData(int fd, int seconds, int useconds=0);
  65 int waitFor2Data(int fd1, int fd2, int seconds, int useconds, int* fd);
  66 int waitForMultiData(const set<int>& fds, const int seconds, const int useconds, int* fd);
  67 int waitForRWData(int fd, bool waitForRead, int seconds, int useconds, bool* error=nullptr, bool* disconnected=nullptr);
  68 uint16_t getShort(const unsigned char *p);
  69 uint16_t getShort(const char *p);
  70 uint32_t getLong(const unsigned char *p);
  71 uint32_t getLong(const char *p);
  72 bool getTSIGHashEnum(const DNSName& algoName, TSIGHashEnum& algoEnum);
  73 DNSName getTSIGAlgoName(TSIGHashEnum& algoEnum);
  74
  75 int logFacilityToLOG(unsigned int facility);
  76
  77 struct ServiceTuple
  78 {
  79   string host;
  80   uint16_t port;
  81 };
  82 void parseService(const string &descr, ServiceTuple &st);
  83
  84 template <typename Container>
  85 void
  86 stringtok (Container &container, string const &in,
  87            const char * const delimiters = " \t\n")
  88 {
  89   const string::size_type len = in.length();
  90   string::size_type i = 0;
  91
  92   while (i<len) {
  93     // eat leading whitespace
  94     i = in.find_first_not_of (delimiters, i);
  95     if (i == string::npos)
  96       return;   // nothing left but white space
  97
  98     // find the end of the token
  99     string::size_type j = in.find_first_of (delimiters, i);
 100
 101     // push token
 102     if (j == string::npos) {
 103       container.push_back (in.substr(i));
 104       return;
 105     } else
 106       container.push_back (in.substr(i, j-i));
 107
 108     // set up for next loop
 109     i = j + 1;
 110   }
 111 }
 112
 113 template<typename T> bool rfc1982LessThan(T a, T b)
 114 {
 115   return ((signed)(a - b)) < 0;
 116 }
 117
 118 // fills container with ranges, so {posbegin,posend}
 119 template <typename Container>
 120 void
 121 vstringtok (Container &container, string const &in,
 122            const char * const delimiters = " \t\n")
 123 {
 124   const string::size_type len = in.length();
 125   string::size_type i = 0;
 126
 127   while (i<len) {
 128     // eat leading whitespace
 129     i = in.find_first_not_of (delimiters, i);
 130     if (i == string::npos)
 131       return;   // nothing left but white space
 132
 133     // find the end of the token
 134     string::size_type j = in.find_first_of (delimiters, i);
 135
 136     // push token
 137     if (j == string::npos) {
 138       container.push_back (make_pair(i, len));
 139       return;
 140     } else
 141       container.push_back (make_pair(i, j));
 142
 143     // set up for next loop
 144     i = j + 1;
 145   }
 146 }
 147
 148 size_t writen2(int fd, const void *buf, size_t count);
 149 inline size_t writen2(int fd, const std::string &s) { return writen2(fd, s.data(), s.size()); }
 150 size_t readn2(int fd, void* buffer, size_t len);
 151 size_t readn2WithTimeout(int fd, void* buffer, size_t len, int idleTimeout, int totalTimeout=0);
 152 size_t writen2WithTimeout(int fd, const void * buffer, size_t len, int timeout);
 153
 154 const string toLower(const string &upper);
 155 const string toLowerCanonic(const string &upper);
 156 bool IpToU32(const string &str, uint32_t *ip);
 157 string U32ToIP(uint32_t);
 158 string stringerror();
 159 string netstringerror();
 160 string itoa(int i);
 161 string uitoa(unsigned int i);
 162 string bitFlip(const string &str);
 163
 164 void dropPrivs(int uid, int gid);
 165 int makeGidNumeric(const string &group);
 166 int makeUidNumeric(const string &user);
 167 void cleanSlashes(string &str);
 168
 169 #if defined(_POSIX_THREAD_CPUTIME) && defined(CLOCK_THREAD_CPUTIME_ID)
 170 /** CPUTime measurements */
 171 class CPUTime
 172 {
 173 public:
 174   void start()
 175   {
 176     clock_gettime(CLOCK_THREAD_CPUTIME_ID, &d_start);
 177   }
 178   uint64_t ndiff()
 179   {
 180     struct timespec now;
 181     clock_gettime(CLOCK_THREAD_CPUTIME_ID, &now);
 182     return 1000000000ULL*(now.tv_sec - d_start.tv_sec) + (now.tv_nsec - d_start.tv_nsec);
 183   }
 184 private:
 185   struct timespec d_start;
 186 };
 187 #endif
 188
 189 /** The DTime class can be used for timing statistics with microsecond resolution.
 190 On 32 bits systems this means that 2147 seconds is the longest time that can be measured. */
 191 class DTime
 192 {
 193 public:
 194   DTime(); //!< Does not set the timer for you! Saves lots of gettimeofday() calls
 195   DTime(const DTime &dt);
 196   time_t time();
 197   inline void set();  //!< Reset the timer
 198   inline int udiff(); //!< Return the number of microseconds since the timer was last set.
 199   inline int udiffNoReset(); //!< Return the number of microseconds since the timer was last set.
 200   void setTimeval(const struct timeval& tv)
 201   {
 202     d_set=tv;
 203   }
 204   struct timeval getTimeval()
 205   {
 206     return d_set;
 207   }
 208 private:
 209   struct timeval d_set;
 210 };
 211
 212 inline void DTime::set()
 213 {
 214   gettimeofday(&d_set,0);
 215 }
 216
 217 inline int DTime::udiff()
 218 {
 219   int res=udiffNoReset();
 220   gettimeofday(&d_set,0);
 221   return res;
 222 }
 223
 224 inline int DTime::udiffNoReset()
 225 {
 226   struct timeval now;
 227
 228   gettimeofday(&now,0);
 229   int ret=1000000*(now.tv_sec-d_set.tv_sec)+(now.tv_usec-d_set.tv_usec);
 230   return ret;
 231 }
 232
 233 inline const string toLower(const string &upper)
 234 {
 235   string reply(upper);
 236   const size_t length = reply.length();
 237   char c;
 238   for(unsigned int i = 0; i < length; ++i) {
 239     c = dns_tolower(upper[i]);
 240     if( c != upper[i])
 241       reply[i] = c;
 242   }
 243   return reply;
 244 }
 245
 246 inline const string toLowerCanonic(const string &upper)
 247 {
 248   string reply(upper);
 249   if(!upper.empty()) {
 250     unsigned int i, limit= ( unsigned int ) reply.length();
 251     unsigned char c;
 252     for(i = 0; i < limit ; i++) {
 253       c = dns_tolower(upper[i]);
 254       if(c != upper[i])
 255         reply[i] = c;
 256     }
 257     if(upper[i-1]=='.')
 258       reply.resize(i-1);
 259   }
 260
 261   return reply;
 262 }
 263
 264
 265
 266 // Make s uppercase:
 267 inline string toUpper( const string& s )
 268 {
 269         string r(s);
 270         for( unsigned int i = 0; i < s.length(); i++ ) {
 271           r[i] = dns_toupper(r[i]);
 272         }
 273         return r;
 274 }
 275
 276 inline double getTime()
 277 {
 278   struct timeval now;
 279   gettimeofday(&now,0);
 280
 281   return now.tv_sec+now.tv_usec/1000000.0;
 282 }
 283
 284 inline void unixDie(const string &why)
 285 {
 286   throw runtime_error(why+": "+strerror(errno));
 287 }
 288
 289 string makeHexDump(const string& str);
 290 struct DNSRecord;
 291 struct DNSZoneRecord;
 292 void shuffle(vector<DNSRecord>& rrs);
 293 void shuffle(vector<DNSZoneRecord>& rrs);
 294
 295 void orderAndShuffle(vector<DNSRecord>& rrs);
 296
 297 void normalizeTV(struct timeval& tv);
 298 const struct timeval operator+(const struct timeval& lhs, const struct timeval& rhs);
 299 const struct timeval operator-(const struct timeval& lhs, const struct timeval& rhs);
 300 inline float makeFloat(const struct timeval& tv)
 301 {
 302   return tv.tv_sec + tv.tv_usec/1000000.0f;
 303 }
 304
 305 inline bool operator<(const struct timeval& lhs, const struct timeval& rhs)
 306 {
 307   return make_pair(lhs.tv_sec, lhs.tv_usec) < make_pair(rhs.tv_sec, rhs.tv_usec);
 308 }
 309
 310 inline bool operator<(const struct timespec& lhs, const struct timespec& rhs)
 311 {
 312   return tie(lhs.tv_sec, lhs.tv_nsec) < tie(rhs.tv_sec, rhs.tv_nsec);
 313 }
 314
 315
 316 inline bool pdns_ilexicographical_compare(const std::string& a, const std::string& b)  __attribute__((pure));
 317 inline bool pdns_ilexicographical_compare(const std::string& a, const std::string& b)
 318 {
 319   const unsigned char *aPtr = (const unsigned char*)a.c_str(), *bPtr = (const unsigned char*)b.c_str();
 320   const unsigned char *aEptr = aPtr + a.length(), *bEptr = bPtr + b.length();
 321   while(aPtr != aEptr && bPtr != bEptr) {
 322     if ((*aPtr != *bPtr) && (dns_tolower(*aPtr) - dns_tolower(*bPtr)))
 323       return (dns_tolower(*aPtr) - dns_tolower(*bPtr)) < 0;
 324     aPtr++;
 325     bPtr++;
 326   }
 327   if(aPtr == aEptr && bPtr == bEptr) // strings are equal (in length)
 328     return false;
 329   return aPtr == aEptr; // true if first string was shorter
 330 }
 331
 332 inline bool pdns_iequals(const std::string& a, const std::string& b) __attribute__((pure));
 333 inline bool pdns_iequals(const std::string& a, const std::string& b)
 334 {
 335   if (a.length() != b.length())
 336     return false;
 337
 338   const char *aPtr = a.c_str(), *bPtr = b.c_str();
 339   const char *aEptr = aPtr + a.length();
 340   while(aPtr != aEptr) {
 341     if((*aPtr != *bPtr) && (dns_tolower(*aPtr) != dns_tolower(*bPtr)))
 342       return false;
 343     aPtr++;
 344     bPtr++;
 345   }
 346   return true;
 347 }
 348
 349 inline bool pdns_iequals_ch(const char a, const char b) __attribute__((pure));
 350 inline bool pdns_iequals_ch(const char a, const char b)
 351 {
 352   if ((a != b) && (dns_tolower(a) != dns_tolower(b)))
 353     return false;
 354
 355   return true;
 356 }
 357
 358
 359 typedef unsigned long AtomicCounterInner;
 360 typedef std::atomic<AtomicCounterInner> AtomicCounter ;
 361
 362 // FIXME400 this should probably go?
 363 struct CIStringCompare: public std::binary_function<string, string, bool>
 364 {
 365   bool operator()(const string& a, const string& b) const
 366   {
 367     return pdns_ilexicographical_compare(a, b);
 368   }
 369 };
 370
 371 struct CIStringComparePOSIX
 372 {
 373    bool operator() (const std::string& lhs, const std::string& rhs)
 374    {
 375       std::string::const_iterator a,b;
 376       const std::locale &loc = std::locale("POSIX");
 377       a=lhs.begin();b=rhs.begin();
 378       while(a!=lhs.end()) {
 379           if (b==rhs.end() || std::tolower(*b,loc)<std::tolower(*a,loc)) return false;
 380           else if (std::tolower(*a,loc)<std::tolower(*b,loc)) return true;
 381           ++a;++b;
 382       }
 383       return (b!=rhs.end());
 384    }
 385 };
 386
 387 struct CIStringPairCompare: public std::binary_function<pair<string, uint16_t>, pair<string,uint16_t>, bool>
 388 {
 389   bool operator()(const pair<string, uint16_t>& a, const pair<string, uint16_t>& b) const
 390   {
 391     if(pdns_ilexicographical_compare(a.first, b.first))
 392         return true;
 393     if(pdns_ilexicographical_compare(b.first, a.first))
 394         return false;
 395     return a.second < b.second;
 396   }
 397 };
 398
 399 inline size_t pdns_ci_find(const string& haystack, const string& needle)
 400 {
 401   string::const_iterator it = std::search(haystack.begin(), haystack.end(),
 402     needle.begin(), needle.end(), pdns_iequals_ch);
 403   if (it == haystack.end()) {
 404     // not found
 405     return string::npos;
 406   } else {
 407     return it - haystack.begin();
 408   }
 409 }
 410
 411 pair<string, string> splitField(const string& inp, char sepa);
 412
 413 inline bool isCanonical(const string& qname)
 414 {
 415   if(qname.empty())
 416     return false;
 417   return qname[qname.size()-1]=='.';
 418 }
 419
 420 inline DNSName toCanonic(const DNSName& zone, const string& qname)
 421 {
 422   if(qname.size()==1 && qname[0]=='@')
 423     return zone;
 424   if(isCanonical(qname))
 425     return DNSName(qname);
 426   return DNSName(qname) += zone;
 427 }
 428
 429 string stripDot(const string& dom);
 430
 431 int makeIPv6sockaddr(const std::string& addr, struct sockaddr_in6* ret);
 432 int makeIPv4sockaddr(const std::string& str, struct sockaddr_in* ret);
 433 int makeUNsockaddr(const std::string& path, struct sockaddr_un* ret);
 434 bool stringfgets(FILE* fp, std::string& line);
 435
 436 template<typename Index>
 437 std::pair<typename Index::iterator,bool>
 438 replacing_insert(Index& i,const typename Index::value_type& x)
 439 {
 440   std::pair<typename Index::iterator,bool> res=i.insert(x);
 441   if(!res.second)res.second=i.replace(res.first,x);
 442   return res;
 443 }
 444
 445 /** very small regex wrapper */
 446 class Regex
 447 {
 448 public:
 449   /** constructor that accepts the expression to regex */
 450   Regex(const string &expr);
 451
 452   ~Regex()
 453   {
 454     regfree(&d_preg);
 455   }
 456   /** call this to find out if 'line' matches your expression */
 457   bool match(const string &line) const
 458   {
 459     return regexec(&d_preg,line.c_str(),0,0,0)==0;
 460   }
 461   bool match(const DNSName& name) const
 462   {
 463     return match(name.toStringNoDot());
 464   }
 465
 466 private:
 467   regex_t d_preg;
 468 };
 469
 470 class SimpleMatch
 471 {
 472 public:
 473   SimpleMatch(const string &mask, bool caseFold = false): d_mask(mask), d_fold(caseFold)
 474   {
 475   }
 476
 477   bool match(string::const_iterator mi, string::const_iterator mend, string::const_iterator vi, string::const_iterator vend)
 478   {
 479     for(;;++mi) {
 480       if (mi == mend) {
 481         return vi == vend;
 482       } else if (*mi == '?') {
 483         if (vi == vend) return false;
 484         ++vi;
 485       } else if (*mi == '*') {
 486         while(*mi == '*') ++mi;
 487         if (mi == d_mask.end()) return true;
 488         while(vi != vend) {
 489           if (match(mi,mend,vi,vend)) return true;
 490           ++vi;
 491         }
 492         return false;
 493       } else {
 494         if ((mi == mend && vi != vend)||
 495             (mi != mend && vi == vend)) return false;
 496         if (d_fold) {
 497           if (dns_tolower(*mi) != dns_tolower(*vi)) return false;
 498         } else {
 499           if (*mi != *vi) return false;
 500         }
 501         ++vi;
 502       }
 503     }
 504   }
 505
 506   bool match(const string& value) {
 507     return match(d_mask.begin(), d_mask.end(), value.begin(), value.end());
 508   }
 509
 510   bool match(const DNSName& name) {
 511     return match(name.toStringNoDot());
 512   }
 513
 514 private:
 515   string d_mask;
 516   bool d_fold;
 517 };
 518
 519 union ComboAddress;
 520 /* itfIndex is an interface index, as returned by if_nametoindex(). 0 means default. */
 521 void addCMsgSrcAddr(struct msghdr* msgh, void* cmsgbuf, const ComboAddress* source, int itfIndex);
 522
 523 unsigned int getFilenumLimit(bool hardOrSoft=0);
 524 void setFilenumLimit(unsigned int lim);
 525 bool readFileIfThere(const char* fname, std::string* line);
 526 uint32_t burtle(const unsigned char* k, uint32_t length, uint32_t init);
 527 bool setSocketTimestamps(int fd);
 528
 529 //! Sets the socket into blocking mode.
 530 bool setBlocking( int sock );
 531
 532 //! Sets the socket into non-blocking mode.
 533 bool setNonBlocking( int sock );
 534 bool setTCPNoDelay(int sock);
 535 bool setReuseAddr(int sock);
 536 bool isNonBlocking(int sock);
 537 bool setReceiveSocketErrors(int sock, int af);
 538 int closesocket(int fd);
 539 bool setCloseOnExec(int sock);
 540
 541 size_t getPipeBufferSize(int fd);
 542 bool setPipeBufferSize(int fd, size_t size);
 543
 544 uint64_t udpErrorStats(const std::string& str);
 545 uint64_t getRealMemoryUsage(const std::string&);
 546 uint64_t getSpecialMemoryUsage(const std::string&);
 547 uint64_t getOpenFileDescriptors(const std::string&);
 548 uint64_t getCPUTimeUser(const std::string&);
 549 uint64_t getCPUTimeSystem(const std::string&);
 550 std::string getMACAddress(const ComboAddress& ca);
 551 template<typename T, typename... Args>
 552 std::unique_ptr<T> make_unique(Args&&... args)
 553 {
 554     return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
 555 }
 556
 557
 558 template<typename T>
 559 const T& defTer(const T& a, const T& b)
 560 {
 561   return a ? a : b;
 562 }
 563
 564 template<typename P, typename T>
 565 T valueOrEmpty(const P val) {
 566   if (!val) return T{};
 567   return T(val);
 568 }
 569
 570
 571 // I'm not very OCD, but I appreciate loglines like "processing 1 delta", "processing 2 deltas" :-)
 572 template <typename Integer>
 573 const char* addS(Integer siz, typename std::enable_if<std::is_integral<Integer>::value>::type*P=0)
 574 {
 575   if(!siz || siz > 1)
 576     return "s";
 577   else return "";
 578 }
 579
 580 template<typename C>
 581 const char* addS(const C& c, typename std::enable_if<std::is_class<C>::value>::type*P=0)
 582 {
 583   return addS(c.size());
 584 }
 585
 586 template<typename C>
 587 const typename C::value_type::second_type* rplookup(const C& c, const typename C::value_type::first_type& key)
 588 {
 589   auto fnd = c.find(key);
 590   if(fnd == c.end())
 591     return 0;
 592   return &fnd->second;
 593 }
 594
 595 double DiffTime(const struct timespec& first, const struct timespec& second);
 596 double DiffTime(const struct timeval& first, const struct timeval& second);
 597 uid_t strToUID(const string &str);
 598 gid_t strToGID(const string &str);
 599
 600 unsigned int pdns_stou(const std::string& str, size_t * idx = 0, int base = 10);
 601
 602 bool isSettingThreadCPUAffinitySupported();
 603 int mapThreadToCPUList(pthread_t tid, const std::set<int>& cpus);
 604
 605 std::vector<ComboAddress> getResolvers(const std::string& resolvConfPath);