contrib/unbound/services/listen_dnsport.c

   1 /*
   2  * services/listen_dnsport.c - listen on port 53 for incoming DNS queries.
   3  *
   4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
   5  *
   6  * This software is open source.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * Redistributions of source code must retain the above copyright notice,
  13  * this list of conditions and the following disclaimer.
  14  *
  15  * Redistributions in binary form must reproduce the above copyright notice,
  16  * this list of conditions and the following disclaimer in the documentation
  17  * and/or other materials provided with the distribution.
  18  *
  19  * Neither the name of the NLNET LABS nor the names of its contributors may
  20  * be used to endorse or promote products derived from this software without
  21  * specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  */
  35
  36 /**
  37  * \file
  38  *
  39  * This file has functions to get queries from clients.
  40  */
  41 #include "config.h"
  42 #ifdef HAVE_SYS_TYPES_H
  43 #  include <sys/types.h>
  44 #endif
  45 #include <sys/time.h>
  46 #ifdef USE_TCP_FASTOPEN
  47 #include <netinet/tcp.h>
  48 #endif
  49 #include "services/listen_dnsport.h"
  50 #include "services/outside_network.h"
  51 #include "util/netevent.h"
  52 #include "util/log.h"
  53 #include "util/config_file.h"
  54 #include "util/net_help.h"
  55 #include "sldns/sbuffer.h"
  56
  57 #ifdef HAVE_NETDB_H
  58 #include <netdb.h>
  59 #endif
  60 #include <fcntl.h>
  61
  62 #ifdef HAVE_SYS_UN_H
  63 #include <sys/un.h>
  64 #endif
  65
  66 #ifdef HAVE_SYSTEMD
  67 #include <systemd/sd-daemon.h>
  68 #endif
  69
  70 /** number of queued TCP connections for listen() */
  71 #define TCP_BACKLOG 256
  72
  73 /**
  74  * Debug print of the getaddrinfo returned address.
  75  * @param addr: the address returned.
  76  */
  77 static void
  78 verbose_print_addr(struct addrinfo *addr)
  79 {
  80         if(verbosity >= VERB_ALGO) {
  81                 char buf[100];
  82                 void* sinaddr = &((struct sockaddr_in*)addr->ai_addr)->sin_addr;
  83 #ifdef INET6
  84                 if(addr->ai_family == AF_INET6)
  85                         sinaddr = &((struct sockaddr_in6*)addr->ai_addr)->
  86                                 sin6_addr;
  87 #endif /* INET6 */
  88                 if(inet_ntop(addr->ai_family, sinaddr, buf,
  89                         (socklen_t)sizeof(buf)) == 0) {
  90                         (void)strlcpy(buf, "(null)", sizeof(buf));
  91                 }
  92                 buf[sizeof(buf)-1] = 0;
  93                 verbose(VERB_ALGO, "creating %s%s socket %s %d",
  94                         addr->ai_socktype==SOCK_DGRAM?"udp":
  95                         addr->ai_socktype==SOCK_STREAM?"tcp":"otherproto",
  96                         addr->ai_family==AF_INET?"4":
  97                         addr->ai_family==AF_INET6?"6":
  98                         "_otherfam", buf,
  99                         ntohs(((struct sockaddr_in*)addr->ai_addr)->sin_port));
 100         }
 101 }
 102
 103 #ifdef HAVE_SYSTEMD
 104 static int
 105 systemd_get_activated(int family, int socktype, int listen,
 106                       struct sockaddr *addr, socklen_t addrlen,
 107                       const char *path)
 108 {
 109         int i = 0;
 110         int r = 0;
 111         int s = -1;
 112         const char* listen_pid, *listen_fds;
 113
 114         /* We should use "listen" option only for stream protocols. For UDP it should be -1 */
 115
 116         if((r = sd_booted()) < 1) {
 117                 if(r == 0)
 118                         log_warn("systemd is not running");
 119                 else
 120                         log_err("systemd sd_booted(): %s", strerror(-r));
 121                 return -1;
 122         }
 123
 124         listen_pid = getenv("LISTEN_PID");
 125         listen_fds = getenv("LISTEN_FDS");
 126
 127         if (!listen_pid) {
 128                 log_warn("Systemd mandatory ENV variable is not defined: LISTEN_PID");
 129                 return -1;
 130         }
 131
 132         if (!listen_fds) {
 133                 log_warn("Systemd mandatory ENV variable is not defined: LISTEN_FDS");
 134                 return -1;
 135         }
 136
 137         if((r = sd_listen_fds(0)) < 1) {
 138                 if(r == 0)
 139                         log_warn("systemd: did not return socket, check unit configuration");
 140                 else
 141                         log_err("systemd sd_listen_fds(): %s", strerror(-r));
 142                 return -1;
 143         }
 144
 145         for(i = 0; i < r; i++) {
 146                 if(sd_is_socket(SD_LISTEN_FDS_START + i, family, socktype, listen)) {
 147                         s = SD_LISTEN_FDS_START + i;
 148                         break;
 149                 }
 150         }
 151         if (s == -1) {
 152                 if (addr)
 153                         log_err_addr("systemd sd_listen_fds()",
 154                                      "no such socket",
 155                                      (struct sockaddr_storage *)addr, addrlen);
 156                 else
 157                         log_err("systemd sd_listen_fds(): %s", path);
 158         }
 159         return s;
 160 }
 161 #endif
 162
 163 int
 164 create_udp_sock(int family, int socktype, struct sockaddr* addr,
 165         socklen_t addrlen, int v6only, int* inuse, int* noproto,
 166         int rcv, int snd, int listen, int* reuseport, int transparent,
 167         int freebind, int use_systemd)
 168 {
 169         int s;
 170 #if defined(SO_REUSEADDR) || defined(SO_REUSEPORT) || defined(IPV6_USE_MIN_MTU)  || defined(IP_TRANSPARENT) || defined(IP_BINDANY) || defined(IP_FREEBIND) || defined (SO_BINDANY)
 171         int on=1;
 172 #endif
 173 #ifdef IPV6_MTU
 174         int mtu = IPV6_MIN_MTU;
 175 #endif
 176 #if !defined(SO_RCVBUFFORCE) && !defined(SO_RCVBUF)
 177         (void)rcv;
 178 #endif
 179 #if !defined(SO_SNDBUFFORCE) && !defined(SO_SNDBUF)
 180         (void)snd;
 181 #endif
 182 #ifndef IPV6_V6ONLY
 183         (void)v6only;
 184 #endif
 185 #if !defined(IP_TRANSPARENT) && !defined(IP_BINDANY) && !defined(SO_BINDANY)
 186         (void)transparent;
 187 #endif
 188 #if !defined(IP_FREEBIND)
 189         (void)freebind;
 190 #endif
 191 #ifdef HAVE_SYSTEMD
 192         int got_fd_from_systemd = 0;
 193
 194         if (!use_systemd
 195             || (use_systemd
 196                 && (s = systemd_get_activated(family, socktype, -1, addr,
 197                                               addrlen, NULL)) == -1)) {
 198 #else
 199         (void)use_systemd;
 200 #endif
 201         if((s = socket(family, socktype, 0)) == -1) {
 202                 *inuse = 0;
 203 #ifndef USE_WINSOCK
 204                 if(errno == EAFNOSUPPORT || errno == EPROTONOSUPPORT) {
 205                         *noproto = 1;
 206                         return -1;
 207                 }
 208                 log_err("can't create socket: %s", strerror(errno));
 209 #else
 210                 if(WSAGetLastError() == WSAEAFNOSUPPORT ||
 211                         WSAGetLastError() == WSAEPROTONOSUPPORT) {
 212                         *noproto = 1;
 213                         return -1;
 214                 }
 215                 log_err("can't create socket: %s",
 216                         wsa_strerror(WSAGetLastError()));
 217 #endif
 218                 *noproto = 0;
 219                 return -1;
 220         }
 221 #ifdef HAVE_SYSTEMD
 222         } else {
 223                 got_fd_from_systemd = 1;
 224         }
 225 #endif
 226         if(listen) {
 227 #ifdef SO_REUSEADDR
 228                 if(setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (void*)&on,
 229                         (socklen_t)sizeof(on)) < 0) {
 230 #ifndef USE_WINSOCK
 231                         log_err("setsockopt(.. SO_REUSEADDR ..) failed: %s",
 232                                 strerror(errno));
 233                         if(errno != ENOSYS) {
 234                                 close(s);
 235                                 *noproto = 0;
 236                                 *inuse = 0;
 237                                 return -1;
 238                         }
 239 #else
 240                         log_err("setsockopt(.. SO_REUSEADDR ..) failed: %s",
 241                                 wsa_strerror(WSAGetLastError()));
 242                         closesocket(s);
 243                         *noproto = 0;
 244                         *inuse = 0;
 245                         return -1;
 246 #endif
 247                 }
 248 #endif /* SO_REUSEADDR */
 249 #ifdef SO_REUSEPORT
 250                 /* try to set SO_REUSEPORT so that incoming
 251                  * queries are distributed evenly among the receiving threads.
 252                  * Each thread must have its own socket bound to the same port,
 253                  * with SO_REUSEPORT set on each socket.
 254                  */
 255                 if (reuseport && *reuseport &&
 256                     setsockopt(s, SOL_SOCKET, SO_REUSEPORT, (void*)&on,
 257                         (socklen_t)sizeof(on)) < 0) {
 258 #ifdef ENOPROTOOPT
 259                         if(errno != ENOPROTOOPT || verbosity >= 3)
 260                                 log_warn("setsockopt(.. SO_REUSEPORT ..) failed: %s",
 261                                         strerror(errno));
 262 #endif
 263                         /* this option is not essential, we can continue */
 264                         *reuseport = 0;
 265                 }
 266 #else
 267                 (void)reuseport;
 268 #endif /* defined(SO_REUSEPORT) */
 269 #ifdef IP_TRANSPARENT
 270                 if (transparent &&
 271                     setsockopt(s, IPPROTO_IP, IP_TRANSPARENT, (void*)&on,
 272                     (socklen_t)sizeof(on)) < 0) {
 273                         log_warn("setsockopt(.. IP_TRANSPARENT ..) failed: %s",
 274                         strerror(errno));
 275                 }
 276 #elif defined(IP_BINDANY)
 277                 if (transparent &&
 278                     setsockopt(s, (family==AF_INET6? IPPROTO_IPV6:IPPROTO_IP),
 279                     (family == AF_INET6? IPV6_BINDANY:IP_BINDANY),
 280                     (void*)&on, (socklen_t)sizeof(on)) < 0) {
 281                         log_warn("setsockopt(.. IP%s_BINDANY ..) failed: %s",
 282                         (family==AF_INET6?"V6":""), strerror(errno));
 283                 }
 284 #elif defined(SO_BINDANY)
 285                 if (transparent &&
 286                     setsockopt(s, SOL_SOCKET, SO_BINDANY, (void*)&on,
 287                     (socklen_t)sizeof(on)) < 0) {
 288                         log_warn("setsockopt(.. SO_BINDANY ..) failed: %s",
 289                         strerror(errno));
 290                 }
 291 #endif /* IP_TRANSPARENT || IP_BINDANY || SO_BINDANY */
 292         }
 293 #ifdef IP_FREEBIND
 294         if(freebind &&
 295             setsockopt(s, IPPROTO_IP, IP_FREEBIND, (void*)&on,
 296             (socklen_t)sizeof(on)) < 0) {
 297                 log_warn("setsockopt(.. IP_FREEBIND ..) failed: %s",
 298                 strerror(errno));
 299         }
 300 #endif /* IP_FREEBIND */
 301         if(rcv) {
 302 #ifdef SO_RCVBUF
 303                 int got;
 304                 socklen_t slen = (socklen_t)sizeof(got);
 305 #  ifdef SO_RCVBUFFORCE
 306                 /* Linux specific: try to use root permission to override
 307                  * system limits on rcvbuf. The limit is stored in
 308                  * /proc/sys/net/core/rmem_max or sysctl net.core.rmem_max */
 309                 if(setsockopt(s, SOL_SOCKET, SO_RCVBUFFORCE, (void*)&rcv,
 310                         (socklen_t)sizeof(rcv)) < 0) {
 311                         if(errno != EPERM) {
 312 #    ifndef USE_WINSOCK
 313                                 log_err("setsockopt(..., SO_RCVBUFFORCE, "
 314                                         "...) failed: %s", strerror(errno));
 315                                 close(s);
 316 #    else
 317                                 log_err("setsockopt(..., SO_RCVBUFFORCE, "
 318                                         "...) failed: %s",
 319                                         wsa_strerror(WSAGetLastError()));
 320                                 closesocket(s);
 321 #    endif
 322                                 *noproto = 0;
 323                                 *inuse = 0;
 324                                 return -1;
 325                         }
 326 #  endif /* SO_RCVBUFFORCE */
 327                         if(setsockopt(s, SOL_SOCKET, SO_RCVBUF, (void*)&rcv,
 328                                 (socklen_t)sizeof(rcv)) < 0) {
 329 #  ifndef USE_WINSOCK
 330                                 log_err("setsockopt(..., SO_RCVBUF, "
 331                                         "...) failed: %s", strerror(errno));
 332                                 close(s);
 333 #  else
 334                                 log_err("setsockopt(..., SO_RCVBUF, "
 335                                         "...) failed: %s",
 336                                         wsa_strerror(WSAGetLastError()));
 337                                 closesocket(s);
 338 #  endif
 339                                 *noproto = 0;
 340                                 *inuse = 0;
 341                                 return -1;
 342                         }
 343                         /* check if we got the right thing or if system
 344                          * reduced to some system max.  Warn if so */
 345                         if(getsockopt(s, SOL_SOCKET, SO_RCVBUF, (void*)&got,
 346                                 &slen) >= 0 && got < rcv/2) {
 347                                 log_warn("so-rcvbuf %u was not granted. "
 348                                         "Got %u. To fix: start with "
 349                                         "root permissions(linux) or sysctl "
 350                                         "bigger net.core.rmem_max(linux) or "
 351                                         "kern.ipc.maxsockbuf(bsd) values.",
 352                                         (unsigned)rcv, (unsigned)got);
 353                         }
 354 #  ifdef SO_RCVBUFFORCE
 355                 }
 356 #  endif
 357 #endif /* SO_RCVBUF */
 358         }
 359         /* first do RCVBUF as the receive buffer is more important */
 360         if(snd) {
 361 #ifdef SO_SNDBUF
 362                 int got;
 363                 socklen_t slen = (socklen_t)sizeof(got);
 364 #  ifdef SO_SNDBUFFORCE
 365                 /* Linux specific: try to use root permission to override
 366                  * system limits on sndbuf. The limit is stored in
 367                  * /proc/sys/net/core/wmem_max or sysctl net.core.wmem_max */
 368                 if(setsockopt(s, SOL_SOCKET, SO_SNDBUFFORCE, (void*)&snd,
 369                         (socklen_t)sizeof(snd)) < 0) {
 370                         if(errno != EPERM) {
 371 #    ifndef USE_WINSOCK
 372                                 log_err("setsockopt(..., SO_SNDBUFFORCE, "
 373                                         "...) failed: %s", strerror(errno));
 374                                 close(s);
 375 #    else
 376                                 log_err("setsockopt(..., SO_SNDBUFFORCE, "
 377                                         "...) failed: %s",
 378                                         wsa_strerror(WSAGetLastError()));
 379                                 closesocket(s);
 380 #    endif
 381                                 *noproto = 0;
 382                                 *inuse = 0;
 383                                 return -1;
 384                         }
 385 #  endif /* SO_SNDBUFFORCE */
 386                         if(setsockopt(s, SOL_SOCKET, SO_SNDBUF, (void*)&snd,
 387                                 (socklen_t)sizeof(snd)) < 0) {
 388 #  ifndef USE_WINSOCK
 389                                 log_err("setsockopt(..., SO_SNDBUF, "
 390                                         "...) failed: %s", strerror(errno));
 391                                 close(s);
 392 #  else
 393                                 log_err("setsockopt(..., SO_SNDBUF, "
 394                                         "...) failed: %s",
 395                                         wsa_strerror(WSAGetLastError()));
 396                                 closesocket(s);
 397 #  endif
 398                                 *noproto = 0;
 399                                 *inuse = 0;
 400                                 return -1;
 401                         }
 402                         /* check if we got the right thing or if system
 403                          * reduced to some system max.  Warn if so */
 404                         if(getsockopt(s, SOL_SOCKET, SO_SNDBUF, (void*)&got,
 405                                 &slen) >= 0 && got < snd/2) {
 406                                 log_warn("so-sndbuf %u was not granted. "
 407                                         "Got %u. To fix: start with "
 408                                         "root permissions(linux) or sysctl "
 409                                         "bigger net.core.wmem_max(linux) or "
 410                                         "kern.ipc.maxsockbuf(bsd) values.",
 411                                         (unsigned)snd, (unsigned)got);
 412                         }
 413 #  ifdef SO_SNDBUFFORCE
 414                 }
 415 #  endif
 416 #endif /* SO_SNDBUF */
 417         }
 418         if(family == AF_INET6) {
 419 # if defined(IPV6_V6ONLY)
 420                 if(v6only) {
 421                         int val=(v6only==2)?0:1;
 422                         if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY,
 423                                 (void*)&val, (socklen_t)sizeof(val)) < 0) {
 424 #ifndef USE_WINSOCK
 425                                 log_err("setsockopt(..., IPV6_V6ONLY"
 426                                         ", ...) failed: %s", strerror(errno));
 427                                 close(s);
 428 #else
 429                                 log_err("setsockopt(..., IPV6_V6ONLY"
 430                                         ", ...) failed: %s",
 431                                         wsa_strerror(WSAGetLastError()));
 432                                 closesocket(s);
 433 #endif
 434                                 *noproto = 0;
 435                                 *inuse = 0;
 436                                 return -1;
 437                         }
 438                 }
 439 # endif
 440 # if defined(IPV6_USE_MIN_MTU)
 441                 /*
 442                  * There is no fragmentation of IPv6 datagrams
 443                  * during forwarding in the network. Therefore
 444                  * we do not send UDP datagrams larger than
 445                  * the minimum IPv6 MTU of 1280 octets. The
 446                  * EDNS0 message length can be larger if the
 447                  * network stack supports IPV6_USE_MIN_MTU.
 448                  */
 449                 if (setsockopt(s, IPPROTO_IPV6, IPV6_USE_MIN_MTU,
 450                         (void*)&on, (socklen_t)sizeof(on)) < 0) {
 451 #  ifndef USE_WINSOCK
 452                         log_err("setsockopt(..., IPV6_USE_MIN_MTU, "
 453                                 "...) failed: %s", strerror(errno));
 454                         close(s);
 455 #  else
 456                         log_err("setsockopt(..., IPV6_USE_MIN_MTU, "
 457                                 "...) failed: %s",
 458                                 wsa_strerror(WSAGetLastError()));
 459                         closesocket(s);
 460 #  endif
 461                         *noproto = 0;
 462                         *inuse = 0;
 463                         return -1;
 464                 }
 465 # elif defined(IPV6_MTU)
 466                 /*
 467                  * On Linux, to send no larger than 1280, the PMTUD is
 468                  * disabled by default for datagrams anyway, so we set
 469                  * the MTU to use.
 470                  */
 471                 if (setsockopt(s, IPPROTO_IPV6, IPV6_MTU,
 472                         (void*)&mtu, (socklen_t)sizeof(mtu)) < 0) {
 473 #  ifndef USE_WINSOCK
 474                         log_err("setsockopt(..., IPV6_MTU, ...) failed: %s",
 475                                 strerror(errno));
 476                         close(s);
 477 #  else
 478                         log_err("setsockopt(..., IPV6_MTU, ...) failed: %s",
 479                                 wsa_strerror(WSAGetLastError()));
 480                         closesocket(s);
 481 #  endif
 482                         *noproto = 0;
 483                         *inuse = 0;
 484                         return -1;
 485                 }
 486 # endif /* IPv6 MTU */
 487         } else if(family == AF_INET) {
 488 #  if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
 489 /* linux 3.15 has IP_PMTUDISC_OMIT, Hannes Frederic Sowa made it so that
 490  * PMTU information is not accepted, but fragmentation is allowed
 491  * if and only if the packet size exceeds the outgoing interface MTU
 492  * (and also uses the interface mtu to determine the size of the packets).
 493  * So there won't be any EMSGSIZE error.  Against DNS fragmentation attacks.
 494  * FreeBSD already has same semantics without setting the option. */
 495                 int omit_set = 0;
 496                 int action;
 497 #   if defined(IP_PMTUDISC_OMIT)
 498                 action = IP_PMTUDISC_OMIT;
 499                 if (setsockopt(s, IPPROTO_IP, IP_MTU_DISCOVER,
 500                         &action, (socklen_t)sizeof(action)) < 0) {
 501
 502                         if (errno != EINVAL) {
 503                                 log_err("setsockopt(..., IP_MTU_DISCOVER, IP_PMTUDISC_OMIT...) failed: %s",
 504                                         strerror(errno));
 505
 506 #    ifndef USE_WINSOCK
 507                                 close(s);
 508 #    else
 509                                 closesocket(s);
 510 #    endif
 511                                 *noproto = 0;
 512                                 *inuse = 0;
 513                                 return -1;
 514                         }
 515                 }
 516                 else
 517                 {
 518                     omit_set = 1;
 519                 }
 520 #   endif
 521                 if (omit_set == 0) {
 522                         action = IP_PMTUDISC_DONT;
 523                         if (setsockopt(s, IPPROTO_IP, IP_MTU_DISCOVER,
 524                                 &action, (socklen_t)sizeof(action)) < 0) {
 525                                 log_err("setsockopt(..., IP_MTU_DISCOVER, IP_PMTUDISC_DONT...) failed: %s",
 526                                         strerror(errno));
 527 #    ifndef USE_WINSOCK
 528                                 close(s);
 529 #    else
 530                                 closesocket(s);
 531 #    endif
 532                                 *noproto = 0;
 533                                 *inuse = 0;
 534                                 return -1;
 535                         }
 536                 }
 537 #  elif defined(IP_DONTFRAG)
 538                 int off = 0;
 539                 if (setsockopt(s, IPPROTO_IP, IP_DONTFRAG,
 540                         &off, (socklen_t)sizeof(off)) < 0) {
 541                         log_err("setsockopt(..., IP_DONTFRAG, ...) failed: %s",
 542                                 strerror(errno));
 543 #    ifndef USE_WINSOCK
 544                         close(s);
 545 #    else
 546                         closesocket(s);
 547 #    endif
 548                         *noproto = 0;
 549                         *inuse = 0;
 550                         return -1;
 551                 }
 552 #  endif /* IPv4 MTU */
 553         }
 554         if(
 555 #ifdef HAVE_SYSTEMD
 556                 !got_fd_from_systemd &&
 557 #endif
 558                 bind(s, (struct sockaddr*)addr, addrlen) != 0) {
 559                 *noproto = 0;
 560                 *inuse = 0;
 561 #ifndef USE_WINSOCK
 562 #ifdef EADDRINUSE
 563                 *inuse = (errno == EADDRINUSE);
 564                 /* detect freebsd jail with no ipv6 permission */
 565                 if(family==AF_INET6 && errno==EINVAL)
 566                         *noproto = 1;
 567                 else if(errno != EADDRINUSE) {
 568                         log_err_addr("can't bind socket", strerror(errno),
 569                                 (struct sockaddr_storage*)addr, addrlen);
 570                 }
 571 #endif /* EADDRINUSE */
 572                 close(s);
 573 #else /* USE_WINSOCK */
 574                 if(WSAGetLastError() != WSAEADDRINUSE &&
 575                         WSAGetLastError() != WSAEADDRNOTAVAIL) {
 576                         log_err_addr("can't bind socket",
 577                                 wsa_strerror(WSAGetLastError()),
 578                                 (struct sockaddr_storage*)addr, addrlen);
 579                 }
 580                 closesocket(s);
 581 #endif /* USE_WINSOCK */
 582                 return -1;
 583         }
 584         if(!fd_set_nonblock(s)) {
 585                 *noproto = 0;
 586                 *inuse = 0;
 587 #ifndef USE_WINSOCK
 588                 close(s);
 589 #else
 590                 closesocket(s);
 591 #endif
 592                 return -1;
 593         }
 594         return s;
 595 }
 596
 597 int
 598 create_tcp_accept_sock(struct addrinfo *addr, int v6only, int* noproto,
 599         int* reuseport, int transparent, int mss, int freebind, int use_systemd)
 600 {
 601         int s;
 602 #if defined(SO_REUSEADDR) || defined(SO_REUSEPORT) || defined(IPV6_V6ONLY) || defined(IP_TRANSPARENT) || defined(IP_BINDANY) || defined(IP_FREEBIND) || defined(SO_BINDANY)
 603         int on = 1;
 604 #endif
 605 #ifdef HAVE_SYSTEMD
 606         int got_fd_from_systemd = 0;
 607 #endif
 608 #ifdef USE_TCP_FASTOPEN
 609         int qlen;
 610 #endif
 611 #if !defined(IP_TRANSPARENT) && !defined(IP_BINDANY) && !defined(SO_BINDANY)
 612         (void)transparent;
 613 #endif
 614 #if !defined(IP_FREEBIND)
 615         (void)freebind;
 616 #endif
 617         verbose_print_addr(addr);
 618         *noproto = 0;
 619 #ifdef HAVE_SYSTEMD
 620         if (!use_systemd ||
 621             (use_systemd
 622              && (s = systemd_get_activated(addr->ai_family, addr->ai_socktype, 1,
 623                                            addr->ai_addr, addr->ai_addrlen,
 624                                            NULL)) == -1)) {
 625 #else
 626         (void)use_systemd;
 627 #endif
 628         if((s = socket(addr->ai_family, addr->ai_socktype, 0)) == -1) {
 629 #ifndef USE_WINSOCK
 630                 if(errno == EAFNOSUPPORT || errno == EPROTONOSUPPORT) {
 631                         *noproto = 1;
 632                         return -1;
 633                 }
 634                 log_err("can't create socket: %s", strerror(errno));
 635 #else
 636                 if(WSAGetLastError() == WSAEAFNOSUPPORT ||
 637                         WSAGetLastError() == WSAEPROTONOSUPPORT) {
 638                         *noproto = 1;
 639                         return -1;
 640                 }
 641                 log_err("can't create socket: %s",
 642                         wsa_strerror(WSAGetLastError()));
 643 #endif
 644                 return -1;
 645         }
 646         if (mss > 0) {
 647 #if defined(IPPROTO_TCP) && defined(TCP_MAXSEG)
 648                 if(setsockopt(s, IPPROTO_TCP, TCP_MAXSEG, (void*)&mss,
 649                         (socklen_t)sizeof(mss)) < 0) {
 650                         #ifndef USE_WINSOCK
 651                         log_err(" setsockopt(.. TCP_MAXSEG ..) failed: %s",
 652                                 strerror(errno));
 653                         #else
 654                         log_err(" setsockopt(.. TCP_MAXSEG ..) failed: %s",
 655                                 wsa_strerror(WSAGetLastError()));
 656                         #endif
 657                 } else {
 658                         verbose(VERB_ALGO,
 659                                 " tcp socket mss set to %d", mss);
 660                 }
 661 #else
 662                 log_warn(" setsockopt(TCP_MAXSEG) unsupported");
 663 #endif /* defined(IPPROTO_TCP) && defined(TCP_MAXSEG) */
 664         }
 665 #ifdef HAVE_SYSTEMD
 666         } else {
 667                 got_fd_from_systemd = 1;
 668     }
 669 #endif
 670 #ifdef SO_REUSEADDR
 671         if(setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (void*)&on,
 672                 (socklen_t)sizeof(on)) < 0) {
 673 #ifndef USE_WINSOCK
 674                 log_err("setsockopt(.. SO_REUSEADDR ..) failed: %s",
 675                         strerror(errno));
 676                 close(s);
 677 #else
 678                 log_err("setsockopt(.. SO_REUSEADDR ..) failed: %s",
 679                         wsa_strerror(WSAGetLastError()));
 680                 closesocket(s);
 681 #endif
 682                 return -1;
 683         }
 684 #endif /* SO_REUSEADDR */
 685 #ifdef IP_FREEBIND
 686         if (freebind && setsockopt(s, IPPROTO_IP, IP_FREEBIND, (void*)&on,
 687             (socklen_t)sizeof(on)) < 0) {
 688                 log_warn("setsockopt(.. IP_FREEBIND ..) failed: %s",
 689                 strerror(errno));
 690         }
 691 #endif /* IP_FREEBIND */
 692 #ifdef SO_REUSEPORT
 693         /* try to set SO_REUSEPORT so that incoming
 694          * connections are distributed evenly among the receiving threads.
 695          * Each thread must have its own socket bound to the same port,
 696          * with SO_REUSEPORT set on each socket.
 697          */
 698         if (reuseport && *reuseport &&
 699                 setsockopt(s, SOL_SOCKET, SO_REUSEPORT, (void*)&on,
 700                 (socklen_t)sizeof(on)) < 0) {
 701 #ifdef ENOPROTOOPT
 702                 if(errno != ENOPROTOOPT || verbosity >= 3)
 703                         log_warn("setsockopt(.. SO_REUSEPORT ..) failed: %s",
 704                                 strerror(errno));
 705 #endif
 706                 /* this option is not essential, we can continue */
 707                 *reuseport = 0;
 708         }
 709 #else
 710         (void)reuseport;
 711 #endif /* defined(SO_REUSEPORT) */
 712 #if defined(IPV6_V6ONLY)
 713         if(addr->ai_family == AF_INET6 && v6only) {
 714                 if(setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY,
 715                         (void*)&on, (socklen_t)sizeof(on)) < 0) {
 716 #ifndef USE_WINSOCK
 717                         log_err("setsockopt(..., IPV6_V6ONLY, ...) failed: %s",
 718                                 strerror(errno));
 719                         close(s);
 720 #else
 721                         log_err("setsockopt(..., IPV6_V6ONLY, ...) failed: %s",
 722                                 wsa_strerror(WSAGetLastError()));
 723                         closesocket(s);
 724 #endif
 725                         return -1;
 726                 }
 727         }
 728 #else
 729         (void)v6only;
 730 #endif /* IPV6_V6ONLY */
 731 #ifdef IP_TRANSPARENT
 732         if (transparent &&
 733             setsockopt(s, IPPROTO_IP, IP_TRANSPARENT, (void*)&on,
 734             (socklen_t)sizeof(on)) < 0) {
 735                 log_warn("setsockopt(.. IP_TRANSPARENT ..) failed: %s",
 736                         strerror(errno));
 737         }
 738 #elif defined(IP_BINDANY)
 739         if (transparent &&
 740             setsockopt(s, (addr->ai_family==AF_INET6? IPPROTO_IPV6:IPPROTO_IP),
 741             (addr->ai_family == AF_INET6? IPV6_BINDANY:IP_BINDANY),
 742             (void*)&on, (socklen_t)sizeof(on)) < 0) {
 743                 log_warn("setsockopt(.. IP%s_BINDANY ..) failed: %s",
 744                 (addr->ai_family==AF_INET6?"V6":""), strerror(errno));
 745         }
 746 #elif defined(SO_BINDANY)
 747         if (transparent &&
 748             setsockopt(s, SOL_SOCKET, SO_BINDANY, (void*)&on, (socklen_t)
 749             sizeof(on)) < 0) {
 750                 log_warn("setsockopt(.. SO_BINDANY ..) failed: %s",
 751                 strerror(errno));
 752         }
 753 #endif /* IP_TRANSPARENT || IP_BINDANY || SO_BINDANY */
 754         if(
 755 #ifdef HAVE_SYSTEMD
 756                 !got_fd_from_systemd &&
 757 #endif
 758         bind(s, addr->ai_addr, addr->ai_addrlen) != 0) {
 759 #ifndef USE_WINSOCK
 760                 /* detect freebsd jail with no ipv6 permission */
 761                 if(addr->ai_family==AF_INET6 && errno==EINVAL)
 762                         *noproto = 1;
 763                 else {
 764                         log_err_addr("can't bind socket", strerror(errno),
 765                                 (struct sockaddr_storage*)addr->ai_addr,
 766                                 addr->ai_addrlen);
 767                 }
 768                 close(s);
 769 #else
 770                 log_err_addr("can't bind socket",
 771                         wsa_strerror(WSAGetLastError()),
 772                         (struct sockaddr_storage*)addr->ai_addr,
 773                         addr->ai_addrlen);
 774                 closesocket(s);
 775 #endif
 776                 return -1;
 777         }
 778         if(!fd_set_nonblock(s)) {
 779 #ifndef USE_WINSOCK
 780                 close(s);
 781 #else
 782                 closesocket(s);
 783 #endif
 784                 return -1;
 785         }
 786         if(listen(s, TCP_BACKLOG) == -1) {
 787 #ifndef USE_WINSOCK
 788                 log_err("can't listen: %s", strerror(errno));
 789                 close(s);
 790 #else
 791                 log_err("can't listen: %s", wsa_strerror(WSAGetLastError()));
 792                 closesocket(s);
 793 #endif
 794                 return -1;
 795         }
 796 #ifdef USE_TCP_FASTOPEN
 797         /* qlen specifies how many outstanding TFO requests to allow. Limit is a defense
 798            against IP spoofing attacks as suggested in RFC7413 */
 799 #ifdef __APPLE__
 800         /* OS X implementation only supports qlen of 1 via this call. Actual
 801            value is configured by the net.inet.tcp.fastopen_backlog kernel parm. */
 802         qlen = 1;
 803 #else
 804         /* 5 is recommended on linux */
 805         qlen = 5;
 806 #endif
 807         if ((setsockopt(s, IPPROTO_TCP, TCP_FASTOPEN, &qlen,
 808                   sizeof(qlen))) == -1 ) {
 809 #ifdef ENOPROTOOPT
 810                 /* squelch ENOPROTOOPT: freebsd server mode with kernel support
 811                    disabled, except when verbosity enabled for debugging */
 812                 if(errno != ENOPROTOOPT || verbosity >= 3)
 813 #endif
 814                   log_err("Setting TCP Fast Open as server failed: %s", strerror(errno));
 815         }
 816 #endif
 817         return s;
 818 }
 819
 820 int
 821 create_local_accept_sock(const char *path, int* noproto, int use_systemd)
 822 {
 823 #ifdef HAVE_SYSTEMD
 824         int ret;
 825
 826         if (use_systemd && (ret = systemd_get_activated(AF_LOCAL, SOCK_STREAM, 1, NULL, 0, path)) != -1)
 827                 return ret;
 828         else {
 829 #endif
 830 #ifdef HAVE_SYS_UN_H
 831         int s;
 832         struct sockaddr_un usock;
 833 #ifndef HAVE_SYSTEMD
 834         (void)use_systemd;
 835 #endif
 836
 837         verbose(VERB_ALGO, "creating unix socket %s", path);
 838 #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
 839         /* this member exists on BSDs, not Linux */
 840         usock.sun_len = (unsigned)sizeof(usock);
 841 #endif
 842         usock.sun_family = AF_LOCAL;
 843         /* length is 92-108, 104 on FreeBSD */
 844         (void)strlcpy(usock.sun_path, path, sizeof(usock.sun_path));
 845
 846         if ((s = socket(AF_LOCAL, SOCK_STREAM, 0)) == -1) {
 847                 log_err("Cannot create local socket %s (%s)",
 848                         path, strerror(errno));
 849                 return -1;
 850         }
 851
 852         if (unlink(path) && errno != ENOENT) {
 853                 /* The socket already exists and cannot be removed */
 854                 log_err("Cannot remove old local socket %s (%s)",
 855                         path, strerror(errno));
 856                 goto err;
 857         }
 858
 859         if (bind(s, (struct sockaddr *)&usock,
 860                 (socklen_t)sizeof(struct sockaddr_un)) == -1) {
 861                 log_err("Cannot bind local socket %s (%s)",
 862                         path, strerror(errno));
 863                 goto err;
 864         }
 865
 866         if (!fd_set_nonblock(s)) {
 867                 log_err("Cannot set non-blocking mode");
 868                 goto err;
 869         }
 870
 871         if (listen(s, TCP_BACKLOG) == -1) {
 872                 log_err("can't listen: %s", strerror(errno));
 873                 goto err;
 874         }
 875
 876         (void)noproto; /*unused*/
 877         return s;
 878
 879 err:
 880 #ifndef USE_WINSOCK
 881         close(s);
 882 #else
 883         closesocket(s);
 884 #endif
 885         return -1;
 886
 887 #ifdef HAVE_SYSTEMD
 888         }
 889 #endif
 890 #else
 891         (void)use_systemd;
 892         (void)path;
 893         log_err("Local sockets are not supported");
 894         *noproto = 1;
 895         return -1;
 896 #endif
 897 }
 898
 899
 900 /**
 901  * Create socket from getaddrinfo results
 902  */
 903 static int
 904 make_sock(int stype, const char* ifname, const char* port,
 905         struct addrinfo *hints, int v6only, int* noip6, size_t rcv, size_t snd,
 906         int* reuseport, int transparent, int tcp_mss, int freebind, int use_systemd)
 907 {
 908         struct addrinfo *res = NULL;
 909         int r, s, inuse, noproto;
 910         hints->ai_socktype = stype;
 911         *noip6 = 0;
 912         if((r=getaddrinfo(ifname, port, hints, &res)) != 0 || !res) {
 913 #ifdef USE_WINSOCK
 914                 if(r == EAI_NONAME && hints->ai_family == AF_INET6){
 915                         *noip6 = 1; /* 'Host not found' for IP6 on winXP */
 916                         return -1;
 917                 }
 918 #endif
 919                 log_err("node %s:%s getaddrinfo: %s %s",
 920                         ifname?ifname:"default", port, gai_strerror(r),
 921 #ifdef EAI_SYSTEM
 922                         r==EAI_SYSTEM?(char*)strerror(errno):""
 923 #else
 924                         ""
 925 #endif
 926                 );
 927                 return -1;
 928         }
 929         if(stype == SOCK_DGRAM) {
 930                 verbose_print_addr(res);
 931                 s = create_udp_sock(res->ai_family, res->ai_socktype,
 932                         (struct sockaddr*)res->ai_addr, res->ai_addrlen,
 933                         v6only, &inuse, &noproto, (int)rcv, (int)snd, 1,
 934                         reuseport, transparent, freebind, use_systemd);
 935                 if(s == -1 && inuse) {
 936                         log_err("bind: address already in use");
 937                 } else if(s == -1 && noproto && hints->ai_family == AF_INET6){
 938                         *noip6 = 1;
 939                 }
 940         } else  {
 941                 s = create_tcp_accept_sock(res, v6only, &noproto, reuseport,
 942                         transparent, tcp_mss, freebind, use_systemd);
 943                 if(s == -1 && noproto && hints->ai_family == AF_INET6){
 944                         *noip6 = 1;
 945                 }
 946         }
 947         freeaddrinfo(res);
 948         return s;
 949 }
 950
 951 /** make socket and first see if ifname contains port override info */
 952 static int
 953 make_sock_port(int stype, const char* ifname, const char* port,
 954         struct addrinfo *hints, int v6only, int* noip6, size_t rcv, size_t snd,
 955         int* reuseport, int transparent, int tcp_mss, int freebind, int use_systemd)
 956 {
 957         char* s = strchr(ifname, '@');
 958         if(s) {
 959                 /* override port with ifspec@port */
 960                 char p[16];
 961                 char newif[128];
 962                 if((size_t)(s-ifname) >= sizeof(newif)) {
 963                         log_err("ifname too long: %s", ifname);
 964                         *noip6 = 0;
 965                         return -1;
 966                 }
 967                 if(strlen(s+1) >= sizeof(p)) {
 968                         log_err("portnumber too long: %s", ifname);
 969                         *noip6 = 0;
 970                         return -1;
 971                 }
 972                 (void)strlcpy(newif, ifname, sizeof(newif));
 973                 newif[s-ifname] = 0;
 974                 (void)strlcpy(p, s+1, sizeof(p));
 975                 p[strlen(s+1)]=0;
 976                 return make_sock(stype, newif, p, hints, v6only, noip6,
 977                         rcv, snd, reuseport, transparent, tcp_mss, freebind, use_systemd);
 978         }
 979         return make_sock(stype, ifname, port, hints, v6only, noip6, rcv, snd,
 980                 reuseport, transparent, tcp_mss, freebind, use_systemd);
 981 }
 982
 983 /**
 984  * Add port to open ports list.
 985  * @param list: list head. changed.
 986  * @param s: fd.
 987  * @param ftype: if fd is UDP.
 988  * @return false on failure. list in unchanged then.
 989  */
 990 static int
 991 port_insert(struct listen_port** list, int s, enum listen_type ftype)
 992 {
 993         struct listen_port* item = (struct listen_port*)malloc(
 994                 sizeof(struct listen_port));
 995         if(!item)
 996                 return 0;
 997         item->next = *list;
 998         item->fd = s;
 999         item->ftype = ftype;
1000         *list = item;
1001         return 1;
1002 }
1003
1004 /** set fd to receive source address packet info */
1005 static int
1006 set_recvpktinfo(int s, int family)
1007 {
1008 #if defined(IPV6_RECVPKTINFO) || defined(IPV6_PKTINFO) || (defined(IP_RECVDSTADDR) && defined(IP_SENDSRCADDR)) || defined(IP_PKTINFO)
1009         int on = 1;
1010 #else
1011         (void)s;
1012 #endif
1013         if(family == AF_INET6) {
1014 #           ifdef IPV6_RECVPKTINFO
1015                 if(setsockopt(s, IPPROTO_IPV6, IPV6_RECVPKTINFO,
1016                         (void*)&on, (socklen_t)sizeof(on)) < 0) {
1017                         log_err("setsockopt(..., IPV6_RECVPKTINFO, ...) failed: %s",
1018                                 strerror(errno));
1019                         return 0;
1020                 }
1021 #           elif defined(IPV6_PKTINFO)
1022                 if(setsockopt(s, IPPROTO_IPV6, IPV6_PKTINFO,
1023                         (void*)&on, (socklen_t)sizeof(on)) < 0) {
1024                         log_err("setsockopt(..., IPV6_PKTINFO, ...) failed: %s",
1025                                 strerror(errno));
1026                         return 0;
1027                 }
1028 #           else
1029                 log_err("no IPV6_RECVPKTINFO and no IPV6_PKTINFO option, please "
1030                         "disable interface-automatic or do-ip6 in config");
1031                 return 0;
1032 #           endif /* defined IPV6_RECVPKTINFO */
1033
1034         } else if(family == AF_INET) {
1035 #           ifdef IP_PKTINFO
1036                 if(setsockopt(s, IPPROTO_IP, IP_PKTINFO,
1037                         (void*)&on, (socklen_t)sizeof(on)) < 0) {
1038                         log_err("setsockopt(..., IP_PKTINFO, ...) failed: %s",
1039                                 strerror(errno));
1040                         return 0;
1041                 }
1042 #           elif defined(IP_RECVDSTADDR) && defined(IP_SENDSRCADDR)
1043                 if(setsockopt(s, IPPROTO_IP, IP_RECVDSTADDR,
1044                         (void*)&on, (socklen_t)sizeof(on)) < 0) {
1045                         log_err("setsockopt(..., IP_RECVDSTADDR, ...) failed: %s",
1046                                 strerror(errno));
1047                         return 0;
1048                 }
1049 #           else
1050                 log_err("no IP_SENDSRCADDR or IP_PKTINFO option, please disable "
1051                         "interface-automatic or do-ip4 in config");
1052                 return 0;
1053 #           endif /* IP_PKTINFO */
1054
1055         }
1056         return 1;
1057 }
1058
1059 /** see if interface is ssl, its port number == the ssl port number */
1060 static int
1061 if_is_ssl(const char* ifname, const char* port, int ssl_port,
1062         struct config_strlist* additional_tls_port)
1063 {
1064         struct config_strlist* s;
1065         char* p = strchr(ifname, '@');
1066         if(!p && atoi(port) == ssl_port)
1067                 return 1;
1068         if(p && atoi(p+1) == ssl_port)
1069                 return 1;
1070         for(s = additional_tls_port; s; s = s->next) {
1071                 if(p && atoi(p+1) == atoi(s->str))
1072                         return 1;
1073                 if(!p && atoi(port) == atoi(s->str))
1074                         return 1;
1075         }
1076         return 0;
1077 }
1078
1079 /**
1080  * Helper for ports_open. Creates one interface (or NULL for default).
1081  * @param ifname: The interface ip address.
1082  * @param do_auto: use automatic interface detection.
1083  *      If enabled, then ifname must be the wildcard name.
1084  * @param do_udp: if udp should be used.
1085  * @param do_tcp: if udp should be used.
1086  * @param hints: for getaddrinfo. family and flags have to be set by caller.
1087  * @param port: Port number to use (as string).
1088  * @param list: list of open ports, appended to, changed to point to list head.
1089  * @param rcv: receive buffer size for UDP
1090  * @param snd: send buffer size for UDP
1091  * @param ssl_port: ssl service port number
1092  * @param additional_tls_port: list of additional ssl service port numbers.
1093  * @param reuseport: try to set SO_REUSEPORT if nonNULL and true.
1094  *      set to false on exit if reuseport failed due to no kernel support.
1095  * @param transparent: set IP_TRANSPARENT socket option.
1096  * @param tcp_mss: maximum segment size of tcp socket. default if zero.
1097  * @param freebind: set IP_FREEBIND socket option.
1098  * @param use_systemd: if true, fetch sockets from systemd.
1099  * @param dnscrypt_port: dnscrypt service port number
1100  * @return: returns false on error.
1101  */
1102 static int
1103 ports_create_if(const char* ifname, int do_auto, int do_udp, int do_tcp,
1104         struct addrinfo *hints, const char* port, struct listen_port** list,
1105         size_t rcv, size_t snd, int ssl_port,
1106         struct config_strlist* additional_tls_port, int* reuseport,
1107         int transparent, int tcp_mss, int freebind, int use_systemd,
1108         int dnscrypt_port)
1109 {
1110         int s, noip6=0;
1111 #ifdef USE_DNSCRYPT
1112         int is_dnscrypt = ((strchr(ifname, '@') &&
1113                         atoi(strchr(ifname, '@')+1) == dnscrypt_port) ||
1114                         (!strchr(ifname, '@') && atoi(port) == dnscrypt_port));
1115 #else
1116         int is_dnscrypt = 0;
1117         (void)dnscrypt_port;
1118 #endif
1119
1120         if(!do_udp && !do_tcp)
1121                 return 0;
1122         if(do_auto) {
1123                 if((s = make_sock_port(SOCK_DGRAM, ifname, port, hints, 1,
1124                         &noip6, rcv, snd, reuseport, transparent,
1125                         tcp_mss, freebind, use_systemd)) == -1) {
1126                         if(noip6) {
1127                                 log_warn("IPv6 protocol not available");
1128                                 return 1;
1129                         }
1130                         return 0;
1131                 }
1132                 /* getting source addr packet info is highly non-portable */
1133                 if(!set_recvpktinfo(s, hints->ai_family)) {
1134 #ifndef USE_WINSOCK
1135                         close(s);
1136 #else
1137                         closesocket(s);
1138 #endif
1139                         return 0;
1140                 }
1141                 if(!port_insert(list, s,
1142                    is_dnscrypt?listen_type_udpancil_dnscrypt:listen_type_udpancil)) {
1143 #ifndef USE_WINSOCK
1144                         close(s);
1145 #else
1146                         closesocket(s);
1147 #endif
1148                         return 0;
1149                 }
1150         } else if(do_udp) {
1151                 /* regular udp socket */
1152                 if((s = make_sock_port(SOCK_DGRAM, ifname, port, hints, 1,
1153                         &noip6, rcv, snd, reuseport, transparent,
1154                         tcp_mss, freebind, use_systemd)) == -1) {
1155                         if(noip6) {
1156                                 log_warn("IPv6 protocol not available");
1157                                 return 1;
1158                         }
1159                         return 0;
1160                 }
1161                 if(!port_insert(list, s,
1162                    is_dnscrypt?listen_type_udp_dnscrypt:listen_type_udp)) {
1163 #ifndef USE_WINSOCK
1164                         close(s);
1165 #else
1166                         closesocket(s);
1167 #endif
1168                         return 0;
1169                 }
1170         }
1171         if(do_tcp) {
1172                 int is_ssl = if_is_ssl(ifname, port, ssl_port,
1173                         additional_tls_port);
1174                 if((s = make_sock_port(SOCK_STREAM, ifname, port, hints, 1,
1175                         &noip6, 0, 0, reuseport, transparent, tcp_mss,
1176                         freebind, use_systemd)) == -1) {
1177                         if(noip6) {
1178                                 /*log_warn("IPv6 protocol not available");*/
1179                                 return 1;
1180                         }
1181                         return 0;
1182                 }
1183                 if(is_ssl)
1184                         verbose(VERB_ALGO, "setup TCP for SSL service");
1185                 if(!port_insert(list, s, is_ssl?listen_type_ssl:
1186                         (is_dnscrypt?listen_type_tcp_dnscrypt:listen_type_tcp))) {
1187 #ifndef USE_WINSOCK
1188                         close(s);
1189 #else
1190                         closesocket(s);
1191 #endif
1192                         return 0;
1193                 }
1194         }
1195         return 1;
1196 }
1197
1198 /**
1199  * Add items to commpoint list in front.
1200  * @param c: commpoint to add.
1201  * @param front: listen struct.
1202  * @return: false on failure.
1203  */
1204 static int
1205 listen_cp_insert(struct comm_point* c, struct listen_dnsport* front)
1206 {
1207         struct listen_list* item = (struct listen_list*)malloc(
1208                 sizeof(struct listen_list));
1209         if(!item)
1210                 return 0;
1211         item->com = c;
1212         item->next = front->cps;
1213         front->cps = item;
1214         return 1;
1215 }
1216
1217 struct listen_dnsport*
1218 listen_create(struct comm_base* base, struct listen_port* ports,
1219         size_t bufsize, int tcp_accept_count, void* sslctx,
1220         struct dt_env* dtenv, comm_point_callback_type* cb, void *cb_arg)
1221 {
1222         struct listen_dnsport* front = (struct listen_dnsport*)
1223                 malloc(sizeof(struct listen_dnsport));
1224         if(!front)
1225                 return NULL;
1226         front->cps = NULL;
1227         front->udp_buff = sldns_buffer_new(bufsize);
1228 #ifdef USE_DNSCRYPT
1229         front->dnscrypt_udp_buff = NULL;
1230 #endif
1231         if(!front->udp_buff) {
1232                 free(front);
1233                 return NULL;
1234         }
1235
1236         /* create comm points as needed */
1237         while(ports) {
1238                 struct comm_point* cp = NULL;
1239                 if(ports->ftype == listen_type_udp ||
1240                    ports->ftype == listen_type_udp_dnscrypt)
1241                         cp = comm_point_create_udp(base, ports->fd,
1242                                 front->udp_buff, cb, cb_arg);
1243                 else if(ports->ftype == listen_type_tcp ||
1244                                 ports->ftype == listen_type_tcp_dnscrypt)
1245                         cp = comm_point_create_tcp(base, ports->fd,
1246                                 tcp_accept_count, bufsize, cb, cb_arg);
1247                 else if(ports->ftype == listen_type_ssl) {
1248                         cp = comm_point_create_tcp(base, ports->fd,
1249                                 tcp_accept_count, bufsize, cb, cb_arg);
1250                         cp->ssl = sslctx;
1251                 } else if(ports->ftype == listen_type_udpancil ||
1252                                   ports->ftype == listen_type_udpancil_dnscrypt)
1253                         cp = comm_point_create_udp_ancil(base, ports->fd,
1254                                 front->udp_buff, cb, cb_arg);
1255                 if(!cp) {
1256                         log_err("can't create commpoint");
1257                         listen_delete(front);
1258                         return NULL;
1259                 }
1260                 cp->dtenv = dtenv;
1261                 cp->do_not_close = 1;
1262 #ifdef USE_DNSCRYPT
1263                 if (ports->ftype == listen_type_udp_dnscrypt ||
1264                         ports->ftype == listen_type_tcp_dnscrypt ||
1265                         ports->ftype == listen_type_udpancil_dnscrypt) {
1266                         cp->dnscrypt = 1;
1267                         cp->dnscrypt_buffer = sldns_buffer_new(bufsize);
1268                         if(!cp->dnscrypt_buffer) {
1269                                 log_err("can't alloc dnscrypt_buffer");
1270                                 comm_point_delete(cp);
1271                                 listen_delete(front);
1272                                 return NULL;
1273                         }
1274                         front->dnscrypt_udp_buff = cp->dnscrypt_buffer;
1275                 }
1276 #endif
1277                 if(!listen_cp_insert(cp, front)) {
1278                         log_err("malloc failed");
1279                         comm_point_delete(cp);
1280                         listen_delete(front);
1281                         return NULL;
1282                 }
1283                 ports = ports->next;
1284         }
1285         if(!front->cps) {
1286                 log_err("Could not open sockets to accept queries.");
1287                 listen_delete(front);
1288                 return NULL;
1289         }
1290
1291         return front;
1292 }
1293
1294 void
1295 listen_list_delete(struct listen_list* list)
1296 {
1297         struct listen_list *p = list, *pn;
1298         while(p) {
1299                 pn = p->next;
1300                 comm_point_delete(p->com);
1301                 free(p);
1302                 p = pn;
1303         }
1304 }
1305
1306 void
1307 listen_delete(struct listen_dnsport* front)
1308 {
1309         if(!front)
1310                 return;
1311         listen_list_delete(front->cps);
1312 #ifdef USE_DNSCRYPT
1313         if(front->dnscrypt_udp_buff &&
1314                 front->udp_buff != front->dnscrypt_udp_buff) {
1315                 sldns_buffer_free(front->dnscrypt_udp_buff);
1316         }
1317 #endif
1318         sldns_buffer_free(front->udp_buff);
1319         free(front);
1320 }
1321
1322 struct listen_port*
1323 listening_ports_open(struct config_file* cfg, int* reuseport)
1324 {
1325         struct listen_port* list = NULL;
1326         struct addrinfo hints;
1327         int i, do_ip4, do_ip6;
1328         int do_tcp, do_auto;
1329         char portbuf[32];
1330         snprintf(portbuf, sizeof(portbuf), "%d", cfg->port);
1331         do_ip4 = cfg->do_ip4;
1332         do_ip6 = cfg->do_ip6;
1333         do_tcp = cfg->do_tcp;
1334         do_auto = cfg->if_automatic && cfg->do_udp;
1335         if(cfg->incoming_num_tcp == 0)
1336                 do_tcp = 0;
1337
1338         /* getaddrinfo */
1339         memset(&hints, 0, sizeof(hints));
1340         hints.ai_flags = AI_PASSIVE;
1341         /* no name lookups on our listening ports */
1342         if(cfg->num_ifs > 0)
1343                 hints.ai_flags |= AI_NUMERICHOST;
1344         hints.ai_family = AF_UNSPEC;
1345 #ifndef INET6
1346         do_ip6 = 0;
1347 #endif
1348         if(!do_ip4 && !do_ip6) {
1349                 return NULL;
1350         }
1351         /* create ip4 and ip6 ports so that return addresses are nice. */
1352         if(do_auto || cfg->num_ifs == 0) {
1353                 if(do_ip6) {
1354                         hints.ai_family = AF_INET6;
1355                         if(!ports_create_if(do_auto?"::0":"::1",
1356                                 do_auto, cfg->do_udp, do_tcp,
1357                                 &hints, portbuf, &list,
1358                                 cfg->so_rcvbuf, cfg->so_sndbuf,
1359                                 cfg->ssl_port, cfg->additional_tls_port,
1360                                 reuseport, cfg->ip_transparent,
1361                                 cfg->tcp_mss, cfg->ip_freebind, cfg->use_systemd,
1362                                 cfg->dnscrypt_port)) {
1363                                 listening_ports_free(list);
1364                                 return NULL;
1365                         }
1366                 }
1367                 if(do_ip4) {
1368                         hints.ai_family = AF_INET;
1369                         if(!ports_create_if(do_auto?"0.0.0.0":"127.0.0.1",
1370                                 do_auto, cfg->do_udp, do_tcp,
1371                                 &hints, portbuf, &list,
1372                                 cfg->so_rcvbuf, cfg->so_sndbuf,
1373                                 cfg->ssl_port, cfg->additional_tls_port,
1374                                 reuseport, cfg->ip_transparent,
1375                                 cfg->tcp_mss, cfg->ip_freebind, cfg->use_systemd,
1376                                 cfg->dnscrypt_port)) {
1377                                 listening_ports_free(list);
1378                                 return NULL;
1379                         }
1380                 }
1381         } else for(i = 0; i<cfg->num_ifs; i++) {
1382                 if(str_is_ip6(cfg->ifs[i])) {
1383                         if(!do_ip6)
1384                                 continue;
1385                         hints.ai_family = AF_INET6;
1386                         if(!ports_create_if(cfg->ifs[i], 0, cfg->do_udp,
1387                                 do_tcp, &hints, portbuf, &list,
1388                                 cfg->so_rcvbuf, cfg->so_sndbuf,
1389                                 cfg->ssl_port, cfg->additional_tls_port,
1390                                 reuseport, cfg->ip_transparent,
1391                                 cfg->tcp_mss, cfg->ip_freebind, cfg->use_systemd,
1392                                 cfg->dnscrypt_port)) {
1393                                 listening_ports_free(list);
1394                                 return NULL;
1395                         }
1396                 } else {
1397                         if(!do_ip4)
1398                                 continue;
1399                         hints.ai_family = AF_INET;
1400                         if(!ports_create_if(cfg->ifs[i], 0, cfg->do_udp,
1401                                 do_tcp, &hints, portbuf, &list,
1402                                 cfg->so_rcvbuf, cfg->so_sndbuf,
1403                                 cfg->ssl_port, cfg->additional_tls_port,
1404                                 reuseport, cfg->ip_transparent,
1405                                 cfg->tcp_mss, cfg->ip_freebind, cfg->use_systemd,
1406                                 cfg->dnscrypt_port)) {
1407                                 listening_ports_free(list);
1408                                 return NULL;
1409                         }
1410                 }
1411         }
1412         return list;
1413 }
1414
1415 void listening_ports_free(struct listen_port* list)
1416 {
1417         struct listen_port* nx;
1418         while(list) {
1419                 nx = list->next;
1420                 if(list->fd != -1) {
1421 #ifndef USE_WINSOCK
1422                         close(list->fd);
1423 #else
1424                         closesocket(list->fd);
1425 #endif
1426                 }
1427                 free(list);
1428                 list = nx;
1429         }
1430 }
1431
1432 size_t listen_get_mem(struct listen_dnsport* listen)
1433 {
1434         struct listen_list* p;
1435         size_t s = sizeof(*listen) + sizeof(*listen->base) +
1436                 sizeof(*listen->udp_buff) +
1437                 sldns_buffer_capacity(listen->udp_buff);
1438 #ifdef USE_DNSCRYPT
1439         s += sizeof(*listen->dnscrypt_udp_buff);
1440         if(listen->udp_buff != listen->dnscrypt_udp_buff){
1441                 s += sldns_buffer_capacity(listen->dnscrypt_udp_buff);
1442         }
1443 #endif
1444         for(p = listen->cps; p; p = p->next) {
1445                 s += sizeof(*p);
1446                 s += comm_point_get_mem(p->com);
1447         }
1448         return s;
1449 }
1450
1451 void listen_stop_accept(struct listen_dnsport* listen)
1452 {
1453         /* do not stop the ones that have no tcp_free list
1454          * (they have already stopped listening) */
1455         struct listen_list* p;
1456         for(p=listen->cps; p; p=p->next) {
1457                 if(p->com->type == comm_tcp_accept &&
1458                         p->com->tcp_free != NULL) {
1459                         comm_point_stop_listening(p->com);
1460                 }
1461         }
1462 }
1463
1464 void listen_start_accept(struct listen_dnsport* listen)
1465 {
1466         /* do not start the ones that have no tcp_free list, it is no
1467          * use to listen to them because they have no free tcp handlers */
1468         struct listen_list* p;
1469         for(p=listen->cps; p; p=p->next) {
1470                 if(p->com->type == comm_tcp_accept &&
1471                         p->com->tcp_free != NULL) {
1472                         comm_point_start_listening(p->com, -1, -1);
1473                 }
1474         }
1475 }
1476