gnu/packages/dns.scm

   1 ;;; GNU Guix --- Functional package management for GNU
   2 ;;; Copyright © 2015 Taylan Ulrich Bayırlı/Kammer <taylanbayirli@gmail.com>
   3 ;;; Copyright © 2016 Mark H Weaver <mhw@netris.org>
   4 ;;; Copyright © 2016 Ricardo Wurmus <rekado@elephly.net>
   5 ;;; Copyright © 2016 Efraim Flashner <efraim@flashner.co.il>
   6 ;;; Copyright © 2016 John Darrington <jmd@gnu.org>
   7 ;;; Copyright © 2016 ng0 <ng0@we.make.ritual.n0.is>
   8 ;;; Copyright © 2016, 2017 Tobias Geerinckx-Rice <me@tobias.gr>
   9 ;;; Copyright © 2016 Marius Bakke <mbakke@fastmail.com>
  10 ;;; Copyright © 2017 Vasile Dumitrascu <va511e@yahoo.com>
  11 ;;; Copyright © 2017 Gregor Giesen <giesen@zaehlwerk.net>
  12 ;;;
  13 ;;; This file is part of GNU Guix.
  14 ;;;
  15 ;;; GNU Guix is free software; you can redistribute it and/or modify it
  16 ;;; under the terms of the GNU General Public License as published by
  17 ;;; the Free Software Foundation; either version 3 of the License, or (at
  18 ;;; your option) any later version.
  19 ;;;
  20 ;;; GNU Guix is distributed in the hope that it will be useful, but
  21 ;;; WITHOUT ANY WARRANTY; without even the implied warranty of
  22 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23 ;;; GNU General Public License for more details.
  24 ;;;
  25 ;;; You should have received a copy of the GNU General Public License
  26 ;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
  27
  28 (define-module (gnu packages dns)
  29   #:use-module (gnu packages admin)
  30   #:use-module (gnu packages autotools)
  31   #:use-module (gnu packages base)
  32   #:use-module (gnu packages databases)
  33   #:use-module (gnu packages crypto)
  34   #:use-module (gnu packages datastructures)
  35   #:use-module (gnu packages flex)
  36   #:use-module (gnu packages glib)
  37   #:use-module (gnu packages groff)
  38   #:use-module (gnu packages groff)
  39   #:use-module (gnu packages libedit)
  40   #:use-module (gnu packages libevent)
  41   #:use-module (gnu packages libidn)
  42   #:use-module (gnu packages linux)
  43   #:use-module (gnu packages ncurses)
  44   #:use-module (gnu packages nettle)
  45   #:use-module (gnu packages perl)
  46   #:use-module (gnu packages pkg-config)
  47   #:use-module (gnu packages protobuf)
  48   #:use-module (gnu packages python)
  49   #:use-module (gnu packages swig)
  50   #:use-module (gnu packages tls)
  51   #:use-module (gnu packages web)
  52   #:use-module (gnu packages xml)
  53   #:use-module ((guix licenses) #:prefix license:)
  54   #:use-module (guix packages)
  55   #:use-module (guix download)
  56   #:use-module (guix utils)
  57   #:use-module (guix build-system gnu))
  58
  59 (define-public dnsmasq
  60   (package
  61     (name "dnsmasq")
  62     (version "2.76")
  63     (source (origin
  64               (method url-fetch)
  65               (uri (string-append
  66                     "http://www.thekelleys.org.uk/dnsmasq/dnsmasq-"
  67                     version ".tar.xz"))
  68               (sha256
  69                (base32
  70                 "15lzih6671gh9knzpl8mxchiml7z5lfqzr7jm2r0rjhrxs6nk4jb"))))
  71     (build-system gnu-build-system)
  72     (native-inputs
  73      `(("pkg-config" ,pkg-config)))
  74     (inputs
  75      `(("dbus" ,dbus)))
  76     (arguments
  77      `(#:phases
  78        (modify-phases %standard-phases (delete 'configure))
  79        #:make-flags (list (string-append "PREFIX=" (assoc-ref %outputs "out"))
  80                           "CC=gcc"
  81                           "COPTS=\"-DHAVE_DBUS\"")
  82        ;; No 'check' target.
  83        #:tests? #f))
  84     (home-page "http://www.thekelleys.org.uk/dnsmasq/doc.html")
  85     (synopsis "Small caching DNS proxy and DHCP/TFTP server")
  86     (description
  87      "Dnsmasq is a lightweight DNS forwarder and DHCP server.  It is designed
  88 to provide DNS and optionally, DHCP, to a small network.  It can serve the
  89 names of local machines which are not in the global DNS.  The DHCP server
  90 integrates with the DNS server and allows machines with DHCP-allocated
  91 addresses to appear in the DNS with names configured either in each host or in
  92 a central configuration file.  Dnsmasq supports static and dynamic DHCP leases
  93 and BOOTP/TFTP for network booting of diskless machines.")
  94     ;; Source files only say GPL2 and GPL3 are allowed.
  95     (license (list license:gpl2 license:gpl3))))
  96
  97 ;; 'bind' is the name of a built-in Guile procedure, which is why we choose a
  98 ;; different name here.
  99 (define-public isc-bind
 100   (package
 101     (name "bind")
 102     (version "9.11.2")
 103     (source (origin
 104               (method url-fetch)
 105               (uri (string-append
 106                     "ftp://ftp.isc.org/isc/bind9/" version "/" name "-"
 107                     version ".tar.gz"))
 108               (sha256
 109                (base32
 110                 "0yn7wgi2y8mpmvbjbkl4va7p0xsnn48m4yjx6ynb1hzp423asikz"))))
 111     (build-system gnu-build-system)
 112     (outputs `("out" "utils"))
 113     (inputs
 114      ;; it would be nice to add GeoIP and gssapi once there is package
 115      `(("libcap" ,libcap)
 116        ("libxml2" ,libxml2)
 117        ("openssl" ,openssl)
 118        ("p11-kit" ,p11-kit)))
 119     (native-inputs `(("perl" ,perl)
 120                      ("net-tools" ,net-tools)))
 121     (arguments
 122      `(#:configure-flags
 123        (list (string-append "--with-openssl="
 124                             (assoc-ref %build-inputs "openssl"))
 125              (string-append "--with-pkcs11="
 126                             (assoc-ref %build-inputs "p11-kit")))
 127        #:phases
 128        (modify-phases %standard-phases
 129          (add-after 'strip 'move-to-utils
 130            (lambda _
 131              (for-each
 132               (lambda (file)
 133                 (let ((target  (string-append (assoc-ref %outputs "utils") file))
 134                       (src  (string-append (assoc-ref %outputs "out") file)))
 135                   (mkdir-p (dirname target))
 136                   (link src target)
 137                   (delete-file src)))
 138               '("/bin/dig" "/bin/delv" "/bin/nslookup" "/bin/host" "/bin/nsupdate"
 139                 "/share/man/man1/dig.1"
 140                 "/share/man/man1/host.1"
 141                 "/share/man/man1/nslookup.1"
 142                 "/share/man/man1/nsupdate.1"))))
 143          ;; When and if guix provides user namespaces for the build process,
 144          ;; then the following can be uncommented and the subsequent "force-test"
 145          ;; will not be necessary.
 146          ;;
 147          ;;   (add-before 'check 'set-up-loopback
 148          ;;     (lambda _
 149          ;;          (system "bin/tests/system/ifconfig.sh up")))
 150          (replace 'check
 151            (lambda _
 152              (zero? (system* "make" "force-test")))))))
 153     (synopsis "An implementation of the Domain Name System")
 154     (description "BIND is an implementation of the @dfn{Domain Name System}
 155 (DNS) protocols for the Internet.  It is a reference implementation of those
 156 protocols, but it is also production-grade software, suitable for use in
 157 high-volume and high-reliability applications. The name BIND stands for
 158 \"Berkeley Internet Name Domain\", because the software originated in the early
 159 1980s at the University of California at Berkeley.")
 160     (home-page "https://www.isc.org/downloads/bind")
 161     (license (list license:mpl2.0))))
 162
 163 (define-public dnscrypt-proxy
 164   (package
 165     (name "dnscrypt-proxy")
 166     (version "1.9.5")
 167     (source (origin
 168               (method url-fetch)
 169               (uri (string-append
 170                     "https://download.dnscrypt.org/dnscrypt-proxy/"
 171                     "dnscrypt-proxy-" version ".tar.bz2"))
 172               (sha256
 173                (base32
 174                 "1dhvklr4dg2vlw108n11xbamacaryyg3dbrg629b76lp7685p7z8"))
 175               (modules '((guix build utils)))
 176               (snippet
 177                ;; Delete bundled libltdl. XXX: This package also bundles
 178                ;; a modified libevent that cannot currently be removed.
 179                '(delete-file-recursively "libltdl"))))
 180     (build-system gnu-build-system)
 181     (arguments
 182      `(#:phases
 183        (modify-phases %standard-phases
 184          (add-after 'unpack 'autoreconf
 185            (lambda _
 186              ;; Re-generate build files due to unbundling ltdl.
 187              ;; TODO: Prevent generating new libltdl and building it.
 188              ;; The system version is still favored and referenced.
 189              (zero? (system* "autoreconf" "-vif")))))))
 190     (native-inputs
 191      `(("pkg-config" ,pkg-config)
 192        ("automake" ,automake)
 193        ("autoconf" ,autoconf)
 194        ("libtool" ,libtool)))
 195     (inputs
 196      `(("libltdl" ,libltdl)
 197        ("libsodium" ,libsodium)))
 198     (home-page "https://www.dnscrypt.org/")
 199     (synopsis "Securely send DNS requests to a remote server")
 200     (description
 201      "@command{dnscrypt-proxy} is a tool for securing communications
 202 between a client and a DNS resolver.  It verifies that responses you get
 203 from a DNS provider was actually sent by that provider, and haven't been
 204 tampered with.  For optimal performance it is recommended to use this as
 205 a forwarder for a caching DNS resolver such as @command{dnsmasq}, but it
 206 can also be used as a normal DNS \"server\".  A list of public dnscrypt
 207 servers is included, and an up-to-date version is available at
 208 @url{https://download.dnscrypt.org/dnscrypt-proxy/dnscrypt-resolvers.csv}.")
 209     (license (list license:isc
 210                    ;; Libevent and src/ext/queue.h is 3-clause BSD.
 211                    license:bsd-3))))
 212
 213 (define-public dnscrypt-wrapper
 214   (package
 215     (name "dnscrypt-wrapper")
 216     (version "0.2.2")
 217     (source (origin
 218               (method url-fetch)
 219               (uri (string-append
 220                     "https://github.com/cofyc/dnscrypt-wrapper/releases"
 221                     "/download/v" version "/" name "-v" version ".tar.bz2"))
 222               (sha256
 223                (base32
 224                 "1vhg4g0r687f51wcdn7z9w1hxapazx6vyh5rsr8wa48sljzd583g"))))
 225     (build-system gnu-build-system)
 226     (arguments
 227      `(#:make-flags '("CC=gcc")
 228        ;; TODO: Tests require ruby-cucumber and ruby-aruba.
 229        #:tests? #f
 230        #:phases
 231        (modify-phases %standard-phases
 232          (add-after 'unpack 'create-configure
 233            (lambda _
 234              (zero? (system* "make" "configure")))))))
 235     (native-inputs
 236      `(("autoconf" ,autoconf)))
 237     (inputs
 238      `(("libevent" ,libevent)
 239        ("libsodium" ,libsodium)))
 240     (home-page "https://github.com/Cofyc/dnscrypt-wrapper")
 241     (synopsis "Server-side dnscrypt proxy")
 242     (description
 243      "@command{dnscrypt-wrapper} is a tool to expose a name server over
 244 the @code{dnscrypt} protocol.  It can be used as an endpoint for the
 245 @command{dnscrypt-proxy} client to securely tunnel DNS requests between
 246 the two.")
 247     (license (list license:isc
 248                    ;; Bundled argparse is MIT. TODO: package and unbundle.
 249                    license:expat
 250                    ;; dns-protocol.h and rfc1035.{c,h} is gpl2 or gpl3 (either).
 251                    license:gpl2
 252                    license:gpl3))))
 253
 254 (define-public libasr
 255   (package
 256     (name "libasr")
 257     (version "201602131606")
 258     (source
 259      (origin
 260        (method url-fetch)
 261        (uri (string-append "https://www.opensmtpd.org/archives/"
 262                            name "-" version ".tar.gz"))
 263        (sha256
 264         (base32
 265          "18kdmbjsxrfai16d66qslp48b1zf7gr8him2jj5dcqgbsl44ls75"))))
 266     (build-system gnu-build-system)
 267     (native-inputs
 268      `(("autoconf" ,autoconf)
 269        ("automake" ,automake)
 270        ("pkg-config" ,pkg-config)
 271        ("groff" ,groff)))
 272     (home-page "https://www.opensmtpd.org")
 273     (synopsis "Asynchronous resolver library by the OpenBSD project")
 274     (description
 275      "libasr is a free, simple and portable asynchronous resolver library.
 276 It allows to run DNS queries and perform hostname resolutions in a fully
 277 asynchronous fashion.")
 278     (license (list license:isc
 279                    license:bsd-2 ; last part of getrrsetbyname_async.c
 280                    license:bsd-3
 281                    (license:non-copyleft "file://LICENSE") ; includes.h
 282                    license:openssl))))
 283
 284 (define-public unbound
 285   (package
 286     (name "unbound")
 287     (version "1.6.3")
 288     (source
 289      (origin
 290        (method url-fetch)
 291        (uri (string-append "https://www.unbound.net/downloads/unbound-"
 292                            version ".tar.gz"))
 293        (sha256
 294         (base32
 295          "0pw4m4z5qspsagxzbjb61xq5bhd57amw26xqvqzi6b8d3mf6azjc"))))
 296     (build-system gnu-build-system)
 297     (outputs '("out" "python"))
 298     (native-inputs
 299      `(("flex" ,flex)
 300        ("swig" ,swig)))
 301     (inputs
 302      `(("expat" ,expat)
 303        ("libevent" ,libevent)
 304        ("protobuf" ,protobuf)
 305        ("python" ,python-3)
 306        ("python-wrapper" ,python-wrapper)
 307        ("openssl" ,openssl)))
 308     (arguments
 309      `(#:configure-flags
 310        (list "--disable-static" ;save space and non-determinism in libunbound.a
 311              (string-append
 312               "--with-ssl=" (assoc-ref %build-inputs "openssl"))
 313              (string-append
 314               "--with-libevent=" (assoc-ref %build-inputs "libevent"))
 315              (string-append
 316               "--with-libexpat=" (assoc-ref %build-inputs "expat"))
 317              "--with-pythonmodule" "--with-pyunbound")
 318        #:phases
 319        (modify-phases %standard-phases
 320          (add-after 'configure 'fix-python-site-package-path
 321            ;; Move python modules into their own output.
 322            (lambda* (#:key outputs #:allow-other-keys)
 323              (let ((pyout (assoc-ref outputs "python"))
 324                    (ver ,(version-major+minor (package-version python))))
 325                (substitute* "Makefile"
 326                  (("^PYTHON_SITE_PKG=.*$")
 327                   (string-append
 328                    "PYTHON_SITE_PKG="
 329                    pyout "/lib/python-" ver "/site-packages\n"))))
 330              #t))
 331          (add-before 'check 'fix-missing-nss-for-tests
 332            ;; Unfortunately, the package's unittests involve some checks
 333            ;; looking up protocols and services which are not provided
 334            ;; by the minimalistic build environment, in particular,
 335            ;; /etc/protocols and /etc/services are missing.
 336            ;; Also, after plain substitution of protocol and service names
 337            ;; in the test data, the tests still fail because the
 338            ;; corresponding Resource Records have been signed by
 339            ;; RRSIG records.
 340            ;; The following LD_PRELOAD library overwrites the glibc
 341            ;; functions ‘get{proto,serv}byname’, ‘getprotobynumber’ and
 342            ;; ‘getservbyport’ providing the few records required for the
 343            ;; unit tests to pass.
 344            (lambda* (#:key inputs outputs #:allow-other-keys)
 345              (let* ((source (assoc-ref %build-inputs "source"))
 346                     (gcc (assoc-ref %build-inputs "gcc")))
 347                (call-with-output-file "/tmp/nss_preload.c"
 348                  (lambda (port)
 349                    (display "#include <stdlib.h>
 350 #include <string.h>
 351 #include <strings.h>
 352
 353 #include <netdb.h>
 354
 355 struct protoent *getprotobyname(const char *name) {
 356   struct protoent *p = malloc(sizeof(struct protoent));
 357   p->p_aliases = malloc(sizeof(char*));
 358   if (strcasecmp(name, \"tcp\") == 0) {
 359     p->p_name = \"tcp\";
 360     p->p_proto = 6;
 361     p->p_aliases[0] = \"TCP\";
 362   } else if (strcasecmp(name, \"udp\") == 0) {
 363     p->p_name = \"udp\";
 364     p->p_proto = 17;
 365     p->p_aliases[0] = \"UDP\";
 366   } else
 367     p = NULL;
 368   return p;
 369 }
 370
 371 struct protoent *getprotobynumber(int proto) {
 372   struct protoent *p = malloc(sizeof(struct protoent));
 373   p->p_aliases = malloc(sizeof(char*));
 374   switch(proto) {
 375   case 6:
 376     p->p_name = \"tcp\";
 377     p->p_proto = 6;
 378     p->p_aliases[0] = \"TCP\";
 379     break;
 380   case 17:
 381     p->p_name = \"udp\";
 382     p->p_proto = 17;
 383     p->p_aliases[0] = \"UDP\";
 384     break;
 385   default:
 386     p = NULL;
 387     break;
 388   }
 389   return p;
 390 }
 391
 392 struct servent *getservbyname(const char *name, const char *proto) {
 393   struct servent *s = malloc(sizeof(struct servent));
 394   char* buf = malloc((strlen(proto)+1)*sizeof(char));
 395   strcpy(buf, proto);
 396   s->s_aliases = malloc(sizeof(char*));
 397   s->s_aliases[0] = NULL;
 398   if (strcasecmp(name, \"domain\") == 0) {
 399     s->s_name = \"domain\";
 400     s->s_port = htons(53);
 401     s->s_proto = buf;
 402   } else
 403     s = NULL;
 404   return s;
 405 }
 406
 407 struct servent *getservbyport(int port, const char *proto) {
 408   char buf[32];
 409   struct servent *s = malloc(sizeof(struct servent));
 410   strcpy(buf, proto);
 411   s->s_aliases = malloc(sizeof(char*));
 412   s->s_aliases[0] = NULL;
 413   switch(port) {
 414   case 53:
 415     s->s_name = \"domain\";
 416     s->s_port = 53;
 417     s->s_proto = \"udp\";
 418     break;
 419   default:
 420     s = NULL;
 421     break;
 422   }
 423   return s;
 424 }" port)))
 425                (system* (string-append gcc "/bin/gcc")
 426                         "-shared" "-fPIC" "-o" "/tmp/nss_preload.so"
 427                         "/tmp/nss_preload.c")
 428                ;; The preload library only affects the unittests.
 429                (substitute* "Makefile"
 430                  (("./unittest")
 431                   "LD_PRELOAD=/tmp/nss_preload.so ./unittest")))
 432              #t)))))
 433     (home-page "https://www.unbound.net")
 434     (synopsis "Validating, recursive, and caching DNS resolver")
 435     (description
 436      "Unbound is a recursive-only caching DNS server which can perform DNSSEC
 437 validation of results.  It implements only a minimal amount of authoritative
 438 service to prevent leakage to the root nameservers: forward lookups for
 439 localhost, reverse for @code{127.0.0.1} and @code{::1}, and NXDOMAIN for zones
 440 served by AS112.  Stub and forward zones are supported.")
 441     (license license:bsd-4)))
 442
 443 (define-public yadifa
 444   (package
 445     (name "yadifa")
 446     (version "2.2.5")
 447     (source
 448      (let ((build "6937"))
 449        (origin
 450          (method url-fetch)
 451          (uri
 452           (string-append "http://cdn.yadifa.eu/sites/default/files/releases/"
 453                          name "-" version "-" build ".tar.gz"))
 454          (sha256
 455           (base32
 456            "146fs52izf6dfwsxal3srpwin2yyl41g31cy4pyvbi5mqy2craj7")))))
 457     (build-system gnu-build-system)
 458     (native-inputs
 459      `(("which" ,which)))
 460     (inputs
 461      `(("openssl" ,openssl)))
 462     (arguments
 463      `(#:phases (modify-phases %standard-phases
 464                   (add-before 'configure 'omit-example-configurations
 465                               (lambda _
 466                                 (substitute* "Makefile.in"
 467                                   ((" (etc|var)") ""))
 468                                 #t)))
 469        #:configure-flags (list "--sysconfdir=/etc"      "--localstatedir=/var"
 470                                "--enable-shared"        "--disable-static"
 471                                "--enable-messages"      "--enable-ctrl"
 472                                "--enable-nsec"          "--enable-nsec3"
 473                                "--enable-tsig"          "--enable-caching")))
 474     (home-page "http://www.yadifa.eu/")
 475     (synopsis "Authoritative DNS name server")
 476     (description "YADIFA is an authoritative name server for the @dfn{Domain
 477 Name System} (DNS).  It aims for both higher performance and a smaller memory
 478 footprint than other implementations, while remaining fully RFC-compliant.
 479 YADIFA supports dynamic record updates and the @dfn{Domain Name System Security
 480 Extensions} (DNSSEC).")
 481     (license license:bsd-3)))
 482
 483 (define-public knot
 484   (package
 485     (name "knot")
 486     (version "2.5.4")
 487     (source (origin
 488               (method url-fetch)
 489               (uri (string-append "https://secure.nic.cz/files/knot-dns/"
 490                                   name "-" version ".tar.xz"))
 491               (sha256
 492                (base32
 493                 "1w14m9pmc8vl9mcgikvwbflwcxwz52l77jq98wvxyxab13lpdpiz"))
 494               (modules '((guix build utils)))
 495               (snippet
 496                '(begin
 497                   ;; Remove bundled libraries and dependencies on them.
 498                   (substitute* "configure"
 499                     (("src/contrib/dnstap/Makefile") ""))
 500                   (substitute* "src/Makefile.in"
 501                     (("contrib/dnstap ") ""))
 502                   (with-directory-excursion "src/contrib"
 503                     (for-each delete-file-recursively
 504                               (list "dnstap" "lmdb")))
 505                   #t))))
 506     (build-system gnu-build-system)
 507     (native-inputs
 508      `(("pkg-config" ,pkg-config)))
 509     (inputs
 510      `(("gnutls" ,gnutls)
 511        ("jansson" ,jansson)
 512        ("libcap-ng" ,libcap-ng)
 513        ("libedit" ,libedit)
 514        ("libidn" ,libidn)
 515        ("liburcu" ,liburcu)
 516        ("lmdb" ,lmdb)
 517        ("ncurses" ,ncurses)
 518        ("nettle" ,nettle)
 519
 520        ;; For ‘pykeymgr’, needed to migrate keys from versions <= 2.4.
 521        ("python" ,python-2)
 522        ("python-lmdb" ,python2-lmdb)))
 523     (arguments
 524      `(#:phases
 525        (modify-phases %standard-phases
 526          (add-before 'configure 'disable-directory-pre-creation
 527            (lambda _
 528              ;; Don't install empty directories like ‘/etc’ outside the store.
 529              (substitute* "src/Makefile.in" (("\\$\\(INSTALL\\) -d") "true"))
 530              #t))
 531          (replace 'install
 532            (lambda* (#:key outputs #:allow-other-keys)
 533              (let* ((out (assoc-ref outputs "out"))
 534                     (doc (string-append out "/share/doc/knot"))
 535                     (etc (string-append doc "/examples/etc")))
 536                (zero?
 537                 (system* "make"
 538                          (string-append "config_dir=" etc)
 539                          "install")))))
 540          (add-after 'install 'wrap-python-scripts
 541            (lambda* (#:key outputs #:allow-other-keys)
 542              (let* ((out (assoc-ref outputs "out"))
 543                     (path (getenv "PYTHONPATH")))
 544                (wrap-program (string-append out "/sbin/pykeymgr")
 545                  `("PYTHONPATH" ":" prefix (,path))))
 546              #t)))
 547        #:configure-flags
 548        (list "--sysconfdir=/etc"
 549              "--localstatedir=/var"
 550              "--with-module-rosedb=yes" ; serve static records from a database
 551              (string-append "--with-bash-completions="
 552                             (assoc-ref %outputs "out")
 553                             "/etc/bash_completion.d"))))
 554     (home-page "https://www.knot-dns.cz/")
 555     (synopsis "Authoritative DNS name server")
 556     (description "Knot DNS is an authoritative name server for the @dfn{Domain
 557 Name System} (DNS), designed to meet the needs of root and @dfn{top-level
 558 domain} (TLD) name servers.  It is implemented as a threaded daemon and uses a
 559 number of programming techniques to improve speed.  For example, the responder
 560 is completely lock-free, resulting in a very high response rate.  Other features
 561 include automatic @dfn{DNS Security Extensions} (DNSSEC) signing, dynamic record
 562 synthesis, and on-the-fly re-configuration.")
 563     (license (list license:expat        ; src/contrib/{hat-trie,murmurhash3}
 564                    license:lgpl2.0+     ; parts of scr/contrib/ucw
 565                    license:gpl3+))))    ; everything else