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 waitForRWData(int fd, bool waitForRead, int seconds, int useconds, bool* error=nullptr, bool* disconnected=nullptr);
  67 uint16_t getShort(const unsigned char *p);
  68 uint16_t getShort(const char *p);
  69 uint32_t getLong(const unsigned char *p);
  70 uint32_t getLong(const char *p);
  71 bool getTSIGHashEnum(const DNSName& algoName, TSIGHashEnum& algoEnum);
  72 DNSName getTSIGAlgoName(TSIGHashEnum& algoEnum);
  73
  74 int logFacilityToLOG(unsigned int facility);
  75
  76 struct ServiceTuple
  77 {
  78   string host;
  79   uint16_t port;
  80 };
  81 void parseService(const string &descr, ServiceTuple &st);
  82
  83 template <typename Container>
  84 void
  85 stringtok (Container &container, string const &in,
  86            const char * const delimiters = " \t\n")
  87 {
  88   const string::size_type len = in.length();
  89   string::size_type i = 0;
  90
  91   while (i<len) {
  92     // eat leading whitespace
  93     i = in.find_first_not_of (delimiters, i);
  94     if (i == string::npos)
  95       return;   // nothing left but white space
  96
  97     // find the end of the token
  98     string::size_type j = in.find_first_of (delimiters, i);
  99
 100     // push token
 101     if (j == string::npos) {
 102       container.push_back (in.substr(i));
 103       return;
 104     } else
 105       container.push_back (in.substr(i, j-i));
 106
 107     // set up for next loop
 108     i = j + 1;
 109   }
 110 }
 111
 112 template<typename T> bool rfc1982LessThan(T a, T b)
 113 {
 114   return ((signed)(a - b)) < 0;
 115 }
 116
 117 // fills container with ranges, so {posbegin,posend}
 118 template <typename Container>
 119 void
 120 vstringtok (Container &container, string const &in,
 121            const char * const delimiters = " \t\n")
 122 {
 123   const string::size_type len = in.length();
 124   string::size_type i = 0;
 125
 126   while (i<len) {
 127     // eat leading whitespace
 128     i = in.find_first_not_of (delimiters, i);
 129     if (i == string::npos)
 130       return;   // nothing left but white space
 131
 132     // find the end of the token
 133     string::size_type j = in.find_first_of (delimiters, i);
 134
 135     // push token
 136     if (j == string::npos) {
 137       container.push_back (make_pair(i, len));
 138       return;
 139     } else
 140       container.push_back (make_pair(i, j));
 141
 142     // set up for next loop
 143     i = j + 1;
 144   }
 145 }
 146
 147 size_t writen2(int fd, const void *buf, size_t count);
 148 inline size_t writen2(int fd, const std::string &s) { return writen2(fd, s.data(), s.size()); }
 149 size_t readn2(int fd, void* buffer, size_t len);
 150 size_t readn2WithTimeout(int fd, void* buffer, size_t len, int idleTimeout, int totalTimeout=0);
 151 size_t writen2WithTimeout(int fd, const void * buffer, size_t len, int timeout);
 152
 153 const string toLower(const string &upper);
 154 const string toLowerCanonic(const string &upper);
 155 bool IpToU32(const string &str, uint32_t *ip);
 156 string U32ToIP(uint32_t);
 157 string stringerror();
 158 string netstringerror();
 159 string itoa(int i);
 160 string uitoa(unsigned int i);
 161 string bitFlip(const string &str);
 162
 163 void dropPrivs(int uid, int gid);
 164 int makeGidNumeric(const string &group);
 165 int makeUidNumeric(const string &user);
 166 void cleanSlashes(string &str);
 167
 168 #if defined(_POSIX_THREAD_CPUTIME) && defined(CLOCK_THREAD_CPUTIME_ID)
 169 /** CPUTime measurements */
 170 class CPUTime
 171 {
 172 public:
 173   void start()
 174   {
 175     clock_gettime(CLOCK_THREAD_CPUTIME_ID, &d_start);
 176   }
 177   uint64_t ndiff()
 178   {
 179     struct timespec now;
 180     clock_gettime(CLOCK_THREAD_CPUTIME_ID, &now);
 181     return 1000000000ULL*(now.tv_sec - d_start.tv_sec) + (now.tv_nsec - d_start.tv_nsec);
 182   }
 183 private:
 184   struct timespec d_start;
 185 };
 186 #endif
 187
 188 /** The DTime class can be used for timing statistics with microsecond resolution.
 189 On 32 bits systems this means that 2147 seconds is the longest time that can be measured. */
 190 class DTime
 191 {
 192 public:
 193   DTime(); //!< Does not set the timer for you! Saves lots of gettimeofday() calls
 194   DTime(const DTime &dt);
 195   time_t time();
 196   inline void set();  //!< Reset the timer
 197   inline int udiff(); //!< Return the number of microseconds since the timer was last set.
 198   inline int udiffNoReset(); //!< Return the number of microseconds since the timer was last set.
 199   void setTimeval(const struct timeval& tv)
 200   {
 201     d_set=tv;
 202   }
 203   struct timeval getTimeval()
 204   {
 205     return d_set;
 206   }
 207 private:
 208   struct timeval d_set;
 209 };
 210
 211 inline void DTime::set()
 212 {
 213   gettimeofday(&d_set,0);
 214 }
 215
 216 inline int DTime::udiff()
 217 {
 218   int res=udiffNoReset();
 219   gettimeofday(&d_set,0);
 220   return res;
 221 }
 222
 223 inline int DTime::udiffNoReset()
 224 {
 225   struct timeval now;
 226
 227   gettimeofday(&now,0);
 228   int ret=1000000*(now.tv_sec-d_set.tv_sec)+(now.tv_usec-d_set.tv_usec);
 229   return ret;
 230 }
 231
 232
 233 inline bool dns_isspace(char c)
 234 {
 235   return c==' ' || c=='\t' || c=='\r' || c=='\n';
 236 }
 237
 238 inline char dns_tolower(char c)
 239 {
 240   if(c>='A' && c<='Z')
 241     c+='a'-'A';
 242   return c;
 243 }
 244
 245 inline char dns_toupper(char c)
 246 {
 247   if(c>='a' && c<='z')
 248     c+='A'-'a';
 249   return c;
 250 }
 251
 252 inline const string toLower(const string &upper)
 253 {
 254   string reply(upper);
 255   char c;
 256   for(unsigned int i = 0; i < reply.length(); i++) {
 257     c = dns_tolower(upper[i]);
 258     if( c != upper[i])
 259       reply[i] = c;
 260   }
 261   return reply;
 262 }
 263
 264 inline const string toLowerCanonic(const string &upper)
 265 {
 266   string reply(upper);
 267   if(!upper.empty()) {
 268     unsigned int i, limit= ( unsigned int ) reply.length();
 269     char c;
 270     for(i = 0; i < limit ; i++) {
 271       c = dns_tolower(upper[i]);
 272       if(c != upper[i])
 273         reply[i] = c;
 274     }
 275     if(upper[i-1]=='.')
 276       reply.resize(i-1);
 277   }
 278
 279   return reply;
 280 }
 281
 282
 283
 284 // Make s uppercase:
 285 inline string toUpper( const string& s )
 286 {
 287         string r(s);
 288         for( unsigned int i = 0; i < s.length(); i++ ) {
 289           r[i] = dns_toupper(r[i]);
 290         }
 291         return r;
 292 }
 293
 294 inline double getTime()
 295 {
 296   struct timeval now;
 297   gettimeofday(&now,0);
 298
 299   return now.tv_sec+now.tv_usec/1000000.0;
 300 }
 301
 302 inline void unixDie(const string &why)
 303 {
 304   throw runtime_error(why+": "+strerror(errno));
 305 }
 306
 307 string makeHexDump(const string& str);
 308 void shuffle(vector<DNSRecord>& rrs);
 309 struct DNSZoneRecord;
 310 void shuffle(vector<DNSZoneRecord>& rrs);
 311
 312 void orderAndShuffle(vector<DNSRecord>& rrs);
 313
 314 void normalizeTV(struct timeval& tv);
 315 const struct timeval operator+(const struct timeval& lhs, const struct timeval& rhs);
 316 const struct timeval operator-(const struct timeval& lhs, const struct timeval& rhs);
 317 inline float makeFloat(const struct timeval& tv)
 318 {
 319   return tv.tv_sec + tv.tv_usec/1000000.0f;
 320 }
 321
 322 inline bool operator<(const struct timeval& lhs, const struct timeval& rhs)
 323 {
 324   return make_pair(lhs.tv_sec, lhs.tv_usec) < make_pair(rhs.tv_sec, rhs.tv_usec);
 325 }
 326
 327 inline bool operator<(const struct timespec& lhs, const struct timespec& rhs)
 328 {
 329   return tie(lhs.tv_sec, lhs.tv_nsec) < tie(rhs.tv_sec, rhs.tv_nsec);
 330 }
 331
 332
 333 inline bool pdns_ilexicographical_compare(const std::string& a, const std::string& b)  __attribute__((pure));
 334 inline bool pdns_ilexicographical_compare(const std::string& a, const std::string& b)
 335 {
 336   const unsigned char *aPtr = (const unsigned char*)a.c_str(), *bPtr = (const unsigned char*)b.c_str();
 337   const unsigned char *aEptr = aPtr + a.length(), *bEptr = bPtr + b.length();
 338   while(aPtr != aEptr && bPtr != bEptr) {
 339     if ((*aPtr != *bPtr) && (dns_tolower(*aPtr) - dns_tolower(*bPtr)))
 340       return (dns_tolower(*aPtr) - dns_tolower(*bPtr)) < 0;
 341     aPtr++;
 342     bPtr++;
 343   }
 344   if(aPtr == aEptr && bPtr == bEptr) // strings are equal (in length)
 345     return false;
 346   return aPtr == aEptr; // true if first string was shorter
 347 }
 348
 349 inline bool pdns_iequals(const std::string& a, const std::string& b) __attribute__((pure));
 350 inline bool pdns_iequals(const std::string& a, const std::string& b)
 351 {
 352   if (a.length() != b.length())
 353     return false;
 354
 355   const char *aPtr = a.c_str(), *bPtr = b.c_str();
 356   const char *aEptr = aPtr + a.length();
 357   while(aPtr != aEptr) {
 358     if((*aPtr != *bPtr) && (dns_tolower(*aPtr) != dns_tolower(*bPtr)))
 359       return false;
 360     aPtr++;
 361     bPtr++;
 362   }
 363   return true;
 364 }
 365
 366 inline bool pdns_iequals_ch(const char a, const char b) __attribute__((pure));
 367 inline bool pdns_iequals_ch(const char a, const char b)
 368 {
 369   if ((a != b) && (dns_tolower(a) != dns_tolower(b)))
 370     return false;
 371
 372   return true;
 373 }
 374
 375
 376 typedef std::atomic<unsigned long> AtomicCounter ;
 377
 378 // FIXME400 this should probably go?
 379 struct CIStringCompare: public std::binary_function<string, string, bool>
 380 {
 381   bool operator()(const string& a, const string& b) const
 382   {
 383     return pdns_ilexicographical_compare(a, b);
 384   }
 385 };
 386
 387 struct CIStringComparePOSIX
 388 {
 389    bool operator() (const std::string& lhs, const std::string& rhs)
 390    {
 391       std::string::const_iterator a,b;
 392       const std::locale &loc = std::locale("POSIX");
 393       a=lhs.begin();b=rhs.begin();
 394       while(a!=lhs.end()) {
 395           if (b==rhs.end() || std::tolower(*b,loc)<std::tolower(*a,loc)) return false;
 396           else if (std::tolower(*a,loc)<std::tolower(*b,loc)) return true;
 397           a++;b++;
 398       }
 399       return (b!=rhs.end());
 400    }
 401 };
 402
 403 struct CIStringPairCompare: public std::binary_function<pair<string, uint16_t>, pair<string,uint16_t>, bool>
 404 {
 405   bool operator()(const pair<string, uint16_t>& a, const pair<string, uint16_t>& b) const
 406   {
 407     if(pdns_ilexicographical_compare(a.first, b.first))
 408         return true;
 409     if(pdns_ilexicographical_compare(b.first, a.first))
 410         return false;
 411     return a.second < b.second;
 412   }
 413 };
 414
 415 inline size_t pdns_ci_find(const string& haystack, const string& needle)
 416 {
 417   string::const_iterator it = std::search(haystack.begin(), haystack.end(),
 418     needle.begin(), needle.end(), pdns_iequals_ch);
 419   if (it == haystack.end()) {
 420     // not found
 421     return string::npos;
 422   } else {
 423     return it - haystack.begin();
 424   }
 425 }
 426
 427 pair<string, string> splitField(const string& inp, char sepa);
 428
 429 inline bool isCanonical(const string& qname)
 430 {
 431   if(qname.empty())
 432     return false;
 433   return qname[qname.size()-1]=='.';
 434 }
 435
 436 inline DNSName toCanonic(const DNSName& zone, const string& qname)
 437 {
 438   if(qname.size()==1 && qname[0]=='@')
 439     return zone;
 440   if(isCanonical(qname))
 441     return DNSName(qname);
 442   return DNSName(qname) += zone;
 443 }
 444
 445 string stripDot(const string& dom);
 446
 447 void seedRandom(const string& source);
 448 int makeIPv6sockaddr(const std::string& addr, struct sockaddr_in6* ret);
 449 int makeIPv4sockaddr(const std::string& str, struct sockaddr_in* ret);
 450 int makeUNsockaddr(const std::string& path, struct sockaddr_un* ret);
 451 bool stringfgets(FILE* fp, std::string& line);
 452
 453 template<typename Index>
 454 std::pair<typename Index::iterator,bool>
 455 replacing_insert(Index& i,const typename Index::value_type& x)
 456 {
 457   std::pair<typename Index::iterator,bool> res=i.insert(x);
 458   if(!res.second)res.second=i.replace(res.first,x);
 459   return res;
 460 }
 461
 462 /** very small regex wrapper */
 463 class Regex
 464 {
 465 public:
 466   /** constructor that accepts the expression to regex */
 467   Regex(const string &expr);
 468
 469   ~Regex()
 470   {
 471     regfree(&d_preg);
 472   }
 473   /** call this to find out if 'line' matches your expression */
 474   bool match(const string &line) const
 475   {
 476     return regexec(&d_preg,line.c_str(),0,0,0)==0;
 477   }
 478   bool match(const DNSName& name) const
 479   {
 480     return match(name.toStringNoDot());
 481   }
 482
 483 private:
 484   regex_t d_preg;
 485 };
 486
 487 class SimpleMatch
 488 {
 489 public:
 490   SimpleMatch(const string &mask, bool caseFold = false)
 491   {
 492     this->d_mask = mask;
 493     this->d_fold = caseFold;
 494   }
 495
 496   bool match(string::const_iterator mi, string::const_iterator mend, string::const_iterator vi, string::const_iterator vend)
 497   {
 498     for(;;mi++) {
 499       if (mi == mend) {
 500         return vi == vend;
 501       } else if (*mi == '?') {
 502         if (vi == vend) return false;
 503         vi++;
 504       } else if (*mi == '*') {
 505         while(*mi == '*') mi++;
 506         if (mi == d_mask.end()) return true;
 507         while(vi != vend) {
 508           if (match(mi,mend,vi,vend)) return true;
 509           vi++;
 510         }
 511         return false;
 512       } else {
 513         if ((mi == mend && vi != vend)||
 514             (mi != mend && vi == vend)) return false;
 515         if (d_fold) {
 516           if (dns_tolower(*mi) != dns_tolower(*vi)) return false;
 517         } else {
 518           if (*mi != *vi) return false;
 519         }
 520         vi++;
 521       }
 522     }
 523   }
 524
 525   bool match(const string& value) {
 526     return match(d_mask.begin(), d_mask.end(), value.begin(), value.end());
 527   }
 528
 529   bool match(const DNSName& name) {
 530     return match(name.toStringNoDot());
 531   }
 532
 533 private:
 534   string d_mask;
 535   bool d_fold;
 536 };
 537
 538 union ComboAddress;
 539 /* itfIndex is an interface index, as returned by if_nametoindex(). 0 means default. */
 540 void addCMsgSrcAddr(struct msghdr* msgh, void* cmsgbuf, const ComboAddress* source, int itfIndex);
 541
 542 unsigned int getFilenumLimit(bool hardOrSoft=0);
 543 void setFilenumLimit(unsigned int lim);
 544 bool readFileIfThere(const char* fname, std::string* line);
 545 uint32_t burtle(const unsigned char* k, uint32_t lengh, uint32_t init);
 546 bool setSocketTimestamps(int fd);
 547
 548 //! Sets the socket into blocking mode.
 549 bool setBlocking( int sock );
 550
 551 //! Sets the socket into non-blocking mode.
 552 bool setNonBlocking( int sock );
 553 bool setTCPNoDelay(int sock);
 554 bool isNonBlocking(int sock);
 555 int closesocket(int fd);
 556 bool setCloseOnExec(int sock);
 557 uint64_t udpErrorStats(const std::string& str);
 558
 559 uint64_t getRealMemoryUsage(const std::string&);
 560 uint64_t getOpenFileDescriptors(const std::string&);
 561 uint64_t getCPUTimeUser(const std::string&);
 562 uint64_t getCPUTimeSystem(const std::string&);
 563 std::string getMACAddress(const ComboAddress& ca);
 564 template<typename T, typename... Args>
 565 std::unique_ptr<T> make_unique(Args&&... args)
 566 {
 567     return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
 568 }
 569
 570
 571 template<typename T>
 572 const T& defTer(const T& a, const T& b)
 573 {
 574   return a ? a : b;
 575 }
 576
 577 template<typename P, typename T>
 578 T valueOrEmpty(const P val) {
 579   if (!val) return T{};
 580   return T(val);
 581 }
 582
 583
 584 // I'm not very OCD, but I appreciate loglines like "processing 1 delta", "processing 2 deltas" :-)
 585 template <typename Integer>
 586 const char* addS(Integer siz, typename std::enable_if<std::is_integral<Integer>::value>::type*P=0)
 587 {
 588   if(!siz || siz > 1)
 589     return "s";
 590   else return "";
 591 }
 592
 593 template<typename C>
 594 const char* addS(const C& c, typename std::enable_if<std::is_class<C>::value>::type*P=0)
 595 {
 596   return addS(c.size());
 597 }
 598
 599 template<typename C>
 600 const typename C::value_type::second_type* rplookup(const C& c, const typename C::value_type::first_type& key)
 601 {
 602   auto fnd = c.find(key);
 603   if(fnd == c.end())
 604     return 0;
 605   return &fnd->second;
 606 }
 607
 608 double DiffTime(const struct timespec& first, const struct timespec& second);
 609 double DiffTime(const struct timeval& first, const struct timeval& second);
 610 uid_t strToUID(const string &str);
 611 gid_t strToGID(const string &str);
 612
 613 unsigned int pdns_stou(const std::string& str, size_t * idx = 0, int base = 10);