glibc/glibc-rh168253-res_init-tests.patch
Florian Weimer 8597553f96 Rebase DNS stub resolver to the glibc 2.26 version
- Support an arbitrary number of search domains (#168253)
- Detect and apply /etc/resolv.conf changes in libresolv (#1374239)
- CVE-2015-5180: DNS stub resolver crash with crafted record type (#1251403)
2017-10-11 14:41:27 +02:00

692 lines
23 KiB
Diff

commit 2714c5f3c95f90977167c1d21326d907fb76b419
Author: Florian Weimer <fweimer@redhat.com>
Date: Fri Jun 2 15:50:36 2017 +0200
resolv: Tests for various versions of res_init
diff --git a/resolv/Makefile b/resolv/Makefile
index d41fd4603d7b7d77..0ebb2af795c6fb7b 100644
--- a/resolv/Makefile
+++ b/resolv/Makefile
@@ -57,6 +57,11 @@ ifeq (yes,$(build-shared))
tests += \
tst-resolv-canonname \
+# uses DEPRECATED_RES_USE_INET6 from <resolv-internal.h>.
+tests += \
+ tst-resolv-res_init \
+ tst-resolv-res_init-thread \
+
endif
# This test sends millions of packets and is rather slow.
@@ -136,6 +141,9 @@ $(objpfx)tst-res_use_inet6: $(objpfx)libresolv.so $(shared-thread-library)
$(objpfx)tst-resolv-basic: $(objpfx)libresolv.so $(shared-thread-library)
$(objpfx)tst-resolv-edns: $(objpfx)libresolv.so $(shared-thread-library)
$(objpfx)tst-resolv-network: $(objpfx)libresolv.so $(shared-thread-library)
+$(objpfx)tst-resolv-res_init: $(libdl) $(objpfx)libresolv.so
+$(objpfx)tst-resolv-res_init-thread: $(libdl) $(objpfx)libresolv.so \
+ $(shared-thread-library)
$(objpfx)tst-resolv-qtypes: $(objpfx)libresolv.so $(shared-thread-library)
$(objpfx)tst-resolv-search: $(objpfx)libresolv.so $(shared-thread-library)
$(objpfx)tst-resolv-canonname: \
diff --git a/resolv/tst-resolv-res_init-skeleton.c b/resolv/tst-resolv-res_init-skeleton.c
new file mode 100644
index 0000000000000000..1d2c475c4b233131
--- /dev/null
+++ b/resolv/tst-resolv-res_init-skeleton.c
@@ -0,0 +1,601 @@
+/* Test parsing of /etc/resolv.conf. Genric version.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* Before including this file, TEST_THREAD has to be defined to 0 or
+ 1, depending on whether the threading tests should be compiled
+ in. */
+
+#include <arpa/inet.h>
+#include <gnu/lib-names.h>
+#include <netdb.h>
+#include <resolv/resolv-internal.h> /* For DEPRECATED_RES_USE_INET6. */
+#include <stdio.h>
+#include <stdlib.h>
+#include <support/capture_subprocess.h>
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/run_diff.h>
+#include <support/support.h>
+#include <support/temp_file.h>
+#include <support/test-driver.h>
+#include <support/xstdio.h>
+#include <support/xunistd.h>
+
+#if TEST_THREAD
+# include <support/xthread.h>
+#endif
+
+/* This is the host name used to ensure predictable behavior of
+ res_init. */
+static const char *const test_hostname = "www.example.com";
+
+/* Path to the test root directory. */
+static char *path_chroot;
+
+/* Path to resolv.conf under path_chroot (outside the chroot). */
+static char *path_resolv_conf;
+
+static void
+prepare (int argc, char **argv)
+{
+ path_chroot = xasprintf ("%s/tst-resolv-res_init-XXXXXX", test_dir);
+ if (mkdtemp (path_chroot) == NULL)
+ FAIL_EXIT1 ("mkdtemp (\"%s\"): %m", path_chroot);
+ add_temp_file (path_chroot);
+
+ /* Create the /etc directory in the chroot environment. */
+ char *path_etc = xasprintf ("%s/etc", path_chroot);
+ xmkdir (path_etc, 0777);
+ add_temp_file (path_etc);
+
+ /* Create an empty resolv.conf file. */
+ path_resolv_conf = xasprintf ("%s/resolv.conf", path_etc);
+ add_temp_file (path_resolv_conf);
+ support_write_file_string (path_resolv_conf, "");
+
+ free (path_etc);
+
+ /* valgrind needs a temporary directory in the chroot. */
+ {
+ char *path_tmp = xasprintf ("%s/tmp", path_chroot);
+ xmkdir (path_tmp, 0777);
+ add_temp_file (path_tmp);
+ free (path_tmp);
+ }
+}
+
+/* Verify that the chroot environment has been set up. */
+static void
+check_chroot_working (void *closure)
+{
+ xchroot (path_chroot);
+ FILE *fp = xfopen (_PATH_RESCONF, "r");
+ xfclose (fp);
+
+ TEST_VERIFY_EXIT (res_init () == 0);
+ TEST_VERIFY (_res.options & RES_INIT);
+
+ char buf[100];
+ if (gethostname (buf, sizeof (buf)) < 0)
+ FAIL_EXIT1 ("gethostname: %m");
+ if (strcmp (buf, test_hostname) != 0)
+ FAIL_EXIT1 ("unexpected host name: %s", buf);
+}
+
+/* If FLAG is set in *OPTIONS, write NAME to FP, and clear it in
+ *OPTIONS. */
+static void
+print_option_flag (FILE *fp, int *options, int flag, const char *name)
+{
+ if (*options & flag)
+ {
+ fprintf (fp, " %s", name);
+ *options &= ~flag;
+ }
+}
+
+/* Write a decoded version of the resolver configuration *RESP to the
+ stream FP. */
+static void
+print_resp (FILE *fp, res_state resp)
+{
+ /* The options directive. */
+ {
+ /* RES_INIT is used internally for tracking initialization. */
+ TEST_VERIFY (resp->options & RES_INIT);
+ /* Also mask out other default flags which cannot be set through
+ the options directive. */
+ int options
+ = resp->options & ~(RES_INIT | RES_RECURSE | RES_DEFNAMES | RES_DNSRCH);
+ if (options != 0
+ || resp->ndots != 1
+ || resp->retrans != RES_TIMEOUT
+ || resp->retry != RES_DFLRETRY)
+ {
+ fputs ("options", fp);
+ if (resp->ndots != 1)
+ fprintf (fp, " ndots:%d", resp->ndots);
+ if (resp->retrans != RES_TIMEOUT)
+ fprintf (fp, " timeout:%d", resp->retrans);
+ if (resp->retry != RES_DFLRETRY)
+ fprintf (fp, " attempts:%d", resp->retry);
+ print_option_flag (fp, &options, RES_USEVC, "use-vc");
+ print_option_flag (fp, &options, DEPRECATED_RES_USE_INET6, "inet6");
+ print_option_flag (fp, &options, RES_ROTATE, "rotate");
+ print_option_flag (fp, &options, RES_USE_EDNS0, "edns0");
+ print_option_flag (fp, &options, RES_SNGLKUP,
+ "single-request");
+ print_option_flag (fp, &options, RES_SNGLKUPREOP,
+ "single-request-reopen");
+ print_option_flag (fp, &options, RES_NOTLDQUERY, "no-tld-query");
+ fputc ('\n', fp);
+ if (options != 0)
+ fprintf (fp, "; error: unresolved option bits: 0x%x\n", options);
+ }
+ }
+
+ /* The search and domain directives. */
+ if (resp->dnsrch[0] != NULL)
+ {
+ fputs ("search", fp);
+ for (int i = 0; i < MAXDNSRCH && resp->dnsrch[i] != NULL; ++i)
+ {
+ fputc (' ', fp);
+ fputs (resp->dnsrch[i], fp);
+ }
+ fputc ('\n', fp);
+ }
+ else if (resp->defdname[0] != '\0')
+ fprintf (fp, "domain %s\n", resp->defdname);
+
+ /* The sortlist directive. */
+ if (resp->nsort > 0)
+ {
+ fputs ("sortlist", fp);
+ for (int i = 0; i < resp->nsort && i < MAXRESOLVSORT; ++i)
+ {
+ char net[20];
+ if (inet_ntop (AF_INET, &resp->sort_list[i].addr,
+ net, sizeof (net)) == NULL)
+ FAIL_EXIT1 ("inet_ntop: %m\n");
+ char mask[20];
+ if (inet_ntop (AF_INET, &resp->sort_list[i].mask,
+ mask, sizeof (mask)) == NULL)
+ FAIL_EXIT1 ("inet_ntop: %m\n");
+ fprintf (fp, " %s/%s", net, mask);
+ }
+ fputc ('\n', fp);
+ }
+
+ /* The nameserver directives. */
+ for (size_t i = 0; i < resp->nscount; ++i)
+ {
+ char host[NI_MAXHOST];
+ char service[NI_MAXSERV];
+
+ /* See get_nsaddr in res_send.c. */
+ void *addr;
+ size_t addrlen;
+ if (resp->nsaddr_list[i].sin_family == 0
+ && resp->_u._ext.nsaddrs[i] != NULL)
+ {
+ addr = resp->_u._ext.nsaddrs[i];
+ addrlen = sizeof (*resp->_u._ext.nsaddrs[i]);
+ }
+ else
+ {
+ addr = &resp->nsaddr_list[i];
+ addrlen = sizeof (resp->nsaddr_list[i]);
+ }
+
+ int ret = getnameinfo (addr, addrlen,
+ host, sizeof (host), service, sizeof (service),
+ NI_NUMERICHOST | NI_NUMERICSERV);
+ if (ret != 0)
+ {
+ if (ret == EAI_SYSTEM)
+ fprintf (fp, "; error: getnameinfo: %m\n");
+ else
+ fprintf (fp, "; error: getnameinfo: %s\n", gai_strerror (ret));
+ }
+ else
+ {
+ fprintf (fp, "nameserver %s\n", host);
+ if (strcmp (service, "53") != 0)
+ fprintf (fp, "; unrepresentable port number %s\n\n", service);
+ }
+ }
+
+ TEST_VERIFY (!ferror (fp));
+}
+
+/* Parameters of one test case. */
+struct test_case
+{
+ /* A short, descriptive name of the test. */
+ const char *name;
+
+ /* The contents of the /etc/resolv.conf file. */
+ const char *conf;
+
+ /* The expected output from print_resp. */
+ const char *expected;
+
+ /* Setting for the LOCALDOMAIN environment variable. NULL if the
+ variable is not to be set. */
+ const char *localdomain;
+
+ /* Setting for the RES_OPTIONS environment variable. NULL if the
+ variable is not to be set. */
+ const char *res_options;
+};
+
+enum test_init
+{
+ test_init,
+ test_ninit,
+ test_mkquery,
+ test_gethostbyname,
+ test_getaddrinfo,
+ test_init_method_last = test_getaddrinfo
+};
+
+/* Closure argument for run_res_init. */
+struct test_context
+{
+ enum test_init init;
+ const struct test_case *t;
+};
+
+static void
+setup_nss_dns_and_chroot (void)
+{
+ /* Load nss_dns outside of the chroot. */
+ if (dlopen (LIBNSS_DNS_SO, RTLD_LAZY) == NULL)
+ FAIL_EXIT1 ("could not load " LIBNSS_DNS_SO ": %s", dlerror ());
+ xchroot (path_chroot);
+ /* Force the use of nss_dns. */
+ __nss_configure_lookup ("hosts", "dns");
+}
+
+/* Run res_ninit or res_init in a subprocess and dump the parsed
+ resolver state to standard output. */
+static void
+run_res_init (void *closure)
+{
+ struct test_context *ctx = closure;
+ TEST_VERIFY (getenv ("LOCALDOMAIN") == NULL);
+ TEST_VERIFY (getenv ("RES_OPTIONS") == NULL);
+ if (ctx->t->localdomain != NULL)
+ setenv ("LOCALDOMAIN", ctx->t->localdomain, 1);
+ if (ctx->t->res_options != NULL)
+ setenv ("RES_OPTIONS", ctx->t->res_options, 1);
+
+ switch (ctx->init)
+ {
+ case test_init:
+ xchroot (path_chroot);
+ TEST_VERIFY (res_init () == 0);
+ print_resp (stdout, &_res);
+ return;
+
+ case test_ninit:
+ xchroot (path_chroot);
+ res_state resp = xmalloc (sizeof (*resp));
+ memset (resp, 0, sizeof (*resp));
+ TEST_VERIFY (res_ninit (resp) == 0);
+ print_resp (stdout, resp);
+ res_nclose (resp);
+ free (resp);
+ return;
+
+ case test_mkquery:
+ xchroot (path_chroot);
+ unsigned char buf[512];
+ TEST_VERIFY (res_mkquery (QUERY, "www.example",
+ C_IN, ns_t_a, NULL, 0,
+ NULL, buf, sizeof (buf)) > 0);
+ print_resp (stdout, &_res);
+ return;
+
+ case test_gethostbyname:
+ setup_nss_dns_and_chroot ();
+ /* Trigger implicit initialization of the _res structure. The
+ actual lookup result is immaterial. */
+ (void )gethostbyname ("www.example");
+ print_resp (stdout, &_res);
+ return;
+
+ case test_getaddrinfo:
+ setup_nss_dns_and_chroot ();
+ /* Trigger implicit initialization of the _res structure. The
+ actual lookup result is immaterial. */
+ struct addrinfo *ai;
+ (void) getaddrinfo ("www.example", NULL, NULL, &ai);
+ print_resp (stdout, &_res);
+ return;
+ }
+
+ FAIL_EXIT1 ("invalid init method %d", ctx->init);
+}
+
+#if TEST_THREAD
+/* Helper function which calls run_res_init from a thread. */
+static void *
+run_res_init_thread_func (void *closure)
+{
+ run_res_init (closure);
+ return NULL;
+}
+
+/* Variant of res_run_init which runs the function on a non-main
+ thread. */
+static void
+run_res_init_on_thread (void *closure)
+{
+ xpthread_join (xpthread_create (NULL, run_res_init_thread_func, closure));
+}
+#endif /* TEST_THREAD */
+
+struct test_case test_cases[] =
+ {
+ {.name = "empty file",
+ .conf = "",
+ .expected = "search example.com\n"
+ "nameserver 127.0.0.1\n"
+ },
+ {.name = "empty file with LOCALDOMAIN",
+ .conf = "",
+ .expected = "search example.net\n"
+ "nameserver 127.0.0.1\n",
+ .localdomain = "example.net",
+ },
+ {.name = "empty file with RES_OPTIONS",
+ .conf = "",
+ .expected = "options attempts:5 edns0\n"
+ "search example.com\n"
+ "nameserver 127.0.0.1\n",
+ .res_options = "edns0 attempts:5",
+ },
+ {.name = "empty file with RES_OPTIONS and LOCALDOMAIN",
+ .conf = "",
+ .expected = "options attempts:5 edns0\n"
+ "search example.org\n"
+ "nameserver 127.0.0.1\n",
+ .localdomain = "example.org",
+ .res_options = "edns0 attempts:5",
+ },
+ {.name = "basic",
+ .conf = "domain example.net\n"
+ "search corp.example.com example.com\n"
+ "nameserver 192.0.2.1\n",
+ .expected = "search corp.example.com example.com\n"
+ "nameserver 192.0.2.1\n"
+ },
+ {.name = "whitespace",
+ .conf = "# This test covers comment and whitespace processing "
+ " (trailing whitespace,\n"
+ "# missing newline at end of file).\n"
+ "\n"
+ "domain example.net\n"
+ ";search commented out\n"
+ "search corp.example.com\texample.com\n"
+ "#nameserver 192.0.2.3\n"
+ "nameserver 192.0.2.1 \n"
+ "nameserver 192.0.2.2", /* No \n at end of file. */
+ .expected = "search corp.example.com example.com\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver 192.0.2.2\n"
+ },
+ {.name = "option values, multiple servers",
+ .conf = "options\tinet6\tndots:3 edns0\tattempts:5\ttimeout:19\n"
+ "domain example.net\n"
+ ";domain comment\n"
+ "search corp.example.com\texample.com\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver ::1\n"
+ "nameserver 192.0.2.2\n",
+ .expected = "options ndots:3 timeout:19 attempts:5 inet6 edns0\n"
+ "search corp.example.com example.com\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver ::1\n"
+ "nameserver 192.0.2.2\n"
+ },
+ {.name = "out-of-range option vales",
+ .conf = "options use-vc timeout:999 attempts:999 ndots:99\n"
+ "search example.com\n",
+ .expected = "options ndots:15 timeout:30 attempts:5 use-vc\n"
+ "search example.com\n"
+ "nameserver 127.0.0.1\n"
+ },
+ {.name = "repeated directives",
+ .conf = "options ndots:3 use-vc\n"
+ "options edns0 ndots:2\n"
+ "domain corp.example\n"
+ "search example.net corp.example.com example.com\n"
+ "search example.org\n"
+ "search\n",
+ .expected = "options ndots:2 use-vc edns0\n"
+ "search example.org\n"
+ "nameserver 127.0.0.1\n"
+ },
+ {.name = "many name servers, sortlist",
+ .conf = "options single-request\n"
+ "search example.org example.com example.net corp.example.com\n"
+ "sortlist 192.0.2.0/255.255.255.0\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver 192.0.2.2\n"
+ "nameserver 192.0.2.3\n"
+ "nameserver 192.0.2.4\n"
+ "nameserver 192.0.2.5\n"
+ "nameserver 192.0.2.6\n"
+ "nameserver 192.0.2.7\n"
+ "nameserver 192.0.2.8\n",
+ .expected = "options single-request\n"
+ "search example.org example.com example.net corp.example.com\n"
+ "sortlist 192.0.2.0/255.255.255.0\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver 192.0.2.2\n"
+ "nameserver 192.0.2.3\n"
+ },
+ {.name = "IPv4 and IPv6 nameservers",
+ .conf = "options single-request\n"
+ "search example.org example.com example.net corp.example.com"
+ " legacy.example.com\n"
+ "sortlist 192.0.2.0\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver 2001:db8::2\n"
+ "nameserver 192.0.2.3\n"
+ "nameserver 2001:db8::4\n"
+ "nameserver 192.0.2.5\n"
+ "nameserver 2001:db8::6\n"
+ "nameserver 192.0.2.7\n"
+ "nameserver 2001:db8::8\n",
+ .expected = "options single-request\n"
+ "search example.org example.com example.net corp.example.com"
+ " legacy.example.com\n"
+ "sortlist 192.0.2.0/255.255.255.0\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver 2001:db8::2\n"
+ "nameserver 192.0.2.3\n"
+ },
+ {.name = "garbage after nameserver",
+ .conf = "nameserver 192.0.2.1 garbage\n"
+ "nameserver 192.0.2.2:5353\n"
+ "nameserver 192.0.2.3 5353\n",
+ .expected = "search example.com\n"
+ "nameserver 192.0.2.1\n"
+ "nameserver 192.0.2.3\n"
+ },
+ {.name = "RES_OPTIONS is cummulative",
+ .conf = "options timeout:7 ndots:2 use-vc\n"
+ "nameserver 192.0.2.1\n",
+ .expected = "options ndots:3 timeout:7 attempts:5 use-vc edns0\n"
+ "search example.com\n"
+ "nameserver 192.0.2.1\n",
+ .res_options = "attempts:5 ndots:3 edns0 ",
+ },
+ { NULL }
+ };
+
+/* Run the indicated test case. This function assumes that the chroot
+ contents has already been set up. */
+static void
+test_file_contents (const struct test_case *t)
+{
+#if TEST_THREAD
+ for (int do_thread = 0; do_thread < 2; ++do_thread)
+#endif
+ for (int init_method = 0; init_method <= test_init_method_last;
+ ++init_method)
+ {
+ if (test_verbose > 0)
+ printf ("info: testing init method %d\n", init_method);
+ struct test_context ctx = { .init = init_method, .t = t };
+ void (*func) (void *) = run_res_init;
+#if TEST_THREAD
+ if (do_thread)
+ func = run_res_init_on_thread;
+#endif
+ struct support_capture_subprocess proc
+ = support_capture_subprocess (func, &ctx);
+ if (strcmp (proc.out.buffer, t->expected) != 0)
+ {
+ support_record_failure ();
+ printf ("error: output mismatch for %s\n", t->name);
+ support_run_diff ("expected", t->expected,
+ "actual", proc.out.buffer);
+ }
+ support_capture_subprocess_check (&proc, t->name, 0,
+ sc_allow_stdout);
+ support_capture_subprocess_free (&proc);
+ }
+}
+
+static int
+do_test (void)
+{
+ support_become_root ();
+ support_enter_network_namespace ();
+ if (!support_in_uts_namespace () || !support_can_chroot ())
+ return EXIT_UNSUPPORTED;
+
+ /* We are in an UTS namespace, so we can set the host name without
+ altering the state of the entire system. */
+ if (sethostname (test_hostname, strlen (test_hostname)) != 0)
+ FAIL_EXIT1 ("sethostname: %m");
+
+ /* These environment variables affect resolv.conf parsing. */
+ unsetenv ("LOCALDOMAIN");
+ unsetenv ("RES_OPTIONS");
+
+ /* Ensure that the chroot setup worked. */
+ {
+ struct support_capture_subprocess proc
+ = support_capture_subprocess (check_chroot_working, NULL);
+ support_capture_subprocess_check (&proc, "chroot", 0, sc_allow_none);
+ support_capture_subprocess_free (&proc);
+ }
+
+ for (size_t i = 0; test_cases[i].name != NULL; ++i)
+ {
+ if (test_verbose > 0)
+ printf ("info: running test: %s\n", test_cases[i].name);
+ TEST_VERIFY (test_cases[i].conf != NULL);
+ TEST_VERIFY (test_cases[i].expected != NULL);
+
+ support_write_file_string (path_resolv_conf, test_cases[i].conf);
+
+ test_file_contents (&test_cases[i]);
+
+ /* The expected output from the empty file test is used for
+ further tests. */
+ if (test_cases[i].conf[0] == '\0')
+ {
+ if (test_verbose > 0)
+ printf ("info: special test: missing file\n");
+ TEST_VERIFY (unlink (path_resolv_conf) == 0);
+ test_file_contents (&test_cases[i]);
+
+ if (test_verbose > 0)
+ printf ("info: special test: dangling symbolic link\n");
+ TEST_VERIFY (symlink ("does-not-exist", path_resolv_conf) == 0);
+ test_file_contents (&test_cases[i]);
+ TEST_VERIFY (unlink (path_resolv_conf) == 0);
+
+ if (test_verbose > 0)
+ printf ("info: special test: unreadable file\n");
+ support_write_file_string (path_resolv_conf, "");
+ TEST_VERIFY (chmod (path_resolv_conf, 0) == 0);
+ test_file_contents (&test_cases[i]);
+
+ /* Restore the empty file. */
+ TEST_VERIFY (unlink (path_resolv_conf) == 0);
+ support_write_file_string (path_resolv_conf, "");
+ }
+ }
+
+ free (path_chroot);
+ path_chroot = NULL;
+ free (path_resolv_conf);
+ path_resolv_conf = NULL;
+ return 0;
+}
+
+#define PREPARE prepare
+#include <support/test-driver.c>
diff --git a/resolv/tst-resolv-res_init-thread.c b/resolv/tst-resolv-res_init-thread.c
new file mode 100644
index 0000000000000000..f47ac34f7fc7a6c8
--- /dev/null
+++ b/resolv/tst-resolv-res_init-thread.c
@@ -0,0 +1,20 @@
+/* Test parsing of /etc/resolv.conf, threading version.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#define TEST_THREAD 1
+#include "tst-resolv-res_init-skeleton.c"
diff --git a/resolv/tst-resolv-res_init.c b/resolv/tst-resolv-res_init.c
new file mode 100644
index 0000000000000000..40c0154eca7363cb
--- /dev/null
+++ b/resolv/tst-resolv-res_init.c
@@ -0,0 +1,20 @@
+/* Test parsing of /etc/resolv.conf, non-threading version.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#define TEST_THREAD 0
+#include "tst-resolv-res_init-skeleton.c"