/* Parse /etc/hosts in multi mode with many addresses/aliases.
Copyright (C) 2017-2018 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/>. */
#include <dlfcn.h>
#include <errno.h>
#include <gnu/lib-names.h>
#include <netdb.h>
#include <nss.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <support/check.h>
#include <support/check_nss.h>
#include <support/namespace.h>
#include <support/support.h>
#include <support/test-driver.h>
#include <support/test-driver.h>
#include <support/xmemstream.h>
#include <support/xstdio.h>
#include <support/xunistd.h>
#include <sys/resource.h>
struct support_chroot *chroot_env;
static void
prepare (int argc, char **argv)
{
chroot_env = support_chroot_create
((struct support_chroot_configuration)
{
.resolv_conf = "",
.hosts = "", /* See write_hosts below. */
.host_conf = "multi on\n",
});
}
/* Create the /etc/hosts file from outside the chroot. */
static void
write_hosts (int count)
{
TEST_VERIFY (count > 0 && count <= 65535);
FILE *fp = xfopen (chroot_env->path_hosts, "w");
fputs ("127.0.0.1 localhost localhost.localdomain\n"
"::1 localhost localhost.localdomain\n",
fp);
for (int i = 0; i < count; ++i)
{
fprintf (fp, "10.4.%d.%d www4.example.com\n",
(i / 256) & 0xff, i & 0xff);
fprintf (fp, "10.46.%d.%d www.example.com\n",
(i / 256) & 0xff, i & 0xff);
fprintf (fp, "192.0.2.1 alias.example.com v4-%d.example.com\n", i);
fprintf (fp, "2001:db8::6:%x www6.example.com\n", i);
fprintf (fp, "2001:db8::46:%x www.example.com\n", i);
fprintf (fp, "2001:db8::1 alias.example.com v6-%d.example.com\n", i);
}
xfclose (fp);
}
/* Parameters of a single test. */
struct test_params
{
const char *name; /* Name to query. */
const char *marker; /* Address marker for the name. */
int count; /* Number of addresses/aliases. */
int family; /* AF_INET, AF_INET_6 or AF_UNSPEC. */
bool canonname; /* True if AI_CANONNAME should be enabled. */
};
/* Expected result of gethostbyname/gethostbyname2. */
static char *
expected_ghbn (const struct test_params *params)
{
TEST_VERIFY (params->family == AF_INET || params->family == AF_INET6);
struct xmemstream expected;
xopen_memstream (&expected);
if (strcmp (params->name, "alias.example.com") == 0)
{
fprintf (expected.out, "name: %s\n", params->name);
char af;
if (params->family == AF_INET)
af = '4';
else
af = '6';
for (int i = 0; i < params->count; ++i)
fprintf (expected.out, "alias: v%c-%d.example.com\n", af, i);
for (int i = 0; i < params->count; ++i)
if (params->family == AF_INET)
fputs ("address: 192.0.2.1\n", expected.out);
else
fputs ("address: 2001:db8::1\n", expected.out);
}
else /* www/www4/www6 name. */
{
bool do_ipv4 = params->family == AF_INET
&& strncmp (params->name, "www6", 4) != 0;
bool do_ipv6 = params->family == AF_INET6
&& strncmp (params->name, "www4", 4) != 0;
if (do_ipv4 || do_ipv6)
{
fprintf (expected.out, "name: %s\n", params->name);
if (do_ipv4)
for (int i = 0; i < params->count; ++i)
fprintf (expected.out, "address: 10.%s.%d.%d\n",
params->marker, i / 256, i % 256);
if (do_ipv6)
for (int i = 0; i < params->count; ++i)
fprintf (expected.out, "address: 2001:db8::%s:%x\n",
params->marker, i);
}
else
fputs ("error: HOST_NOT_FOUND\n", expected.out);
}
xfclose_memstream (&expected);
return expected.buffer;
}
/* Expected result of getaddrinfo. */
static char *
expected_gai (const struct test_params *params)
{
bool do_ipv4 = false;
bool do_ipv6 = false;
if (params->family == AF_UNSPEC)
do_ipv4 = do_ipv6 = true;
else if (params->family == AF_INET)
do_ipv4 = true;
else if (params->family == AF_INET6)
do_ipv6 = true;
struct xmemstream expected;
xopen_memstream (&expected);
if (strcmp (params->name, "alias.example.com") == 0)
{
if (params->canonname)
fprintf (expected.out,
"flags: AI_CANONNAME\n"
"canonname: %s\n",
params->name);
if (do_ipv4)
for (int i = 0; i < params->count; ++i)
fputs ("address: STREAM/TCP 192.0.2.1 80\n", expected.out);
if (do_ipv6)
for (int i = 0; i < params->count; ++i)
fputs ("address: STREAM/TCP 2001:db8::1 80\n", expected.out);
}
else /* www/www4/www6 name. */
{
if (strncmp (params->name, "www4", 4) == 0)
do_ipv6 = false;
else if (strncmp (params->name, "www6", 4) == 0)
do_ipv4 = false;
/* Otherwise, we have www as the name, so we do both. */
if (do_ipv4 || do_ipv6)
{
if (params->canonname)
fprintf (expected.out,
"flags: AI_CANONNAME\n"
"canonname: %s\n",
params->name);
if (do_ipv4)
for (int i = 0; i < params->count; ++i)
fprintf (expected.out, "address: STREAM/TCP 10.%s.%d.%d 80\n",
params->marker, i / 256, i % 256);
if (do_ipv6)
for (int i = 0; i < params->count; ++i)
fprintf (expected.out,
"address: STREAM/TCP 2001:db8::%s:%x 80\n",
params->marker, i);
}
else
fputs ("error: Name or service not known\n", expected.out);
}
xfclose_memstream (&expected);
return expected.buffer;
}
static void
run_gbhn_gai (struct test_params *params)
{
char *ctx = xasprintf ("name=%s marker=%s count=%d family=%d",
params->name, params->marker, params->count,
params->family);
if (test_verbose > 0)
printf ("info: %s\n", ctx);
/* Check gethostbyname, gethostbyname2. */
if (params->family == AF_INET)
{
char *expected = expected_ghbn (params);
check_hostent (ctx, gethostbyname (params->name), expected);
free (expected);
}
if (params->family != AF_UNSPEC)
{
char *expected = expected_ghbn (params);
check_hostent (ctx, gethostbyname2 (params->name, params->family),
expected);
free (expected);
}
/* Check getaddrinfo. */
for (int do_canonical = 0; do_canonical < 2; ++do_canonical)
{
params->canonname = do_canonical;
char *expected = expected_gai (params);
struct addrinfo hints =
{
.ai_family = params->family,
.ai_socktype = SOCK_STREAM,
.ai_protocol = IPPROTO_TCP,
};
if (do_canonical)
hints.ai_flags |= AI_CANONNAME;
struct addrinfo *ai;
int ret = getaddrinfo (params->name, "80", &hints, &ai);
check_addrinfo (ctx, ai, ret, expected);
if (ret == 0)
freeaddrinfo (ai);
free (expected);
}
free (ctx);
}
/* Callback for the subprocess which runs the test in a chroot. */
static void
subprocess (void *closure)
{
struct test_params *params = closure;
xchroot (chroot_env->path_chroot);
static const int families[] = { AF_INET, AF_INET6, AF_UNSPEC, -1 };
static const char *const names[] =
{
"www.example.com", "www4.example.com", "www6.example.com",
"alias.example.com",
NULL
};
static const char *const names_marker[] = { "46", "4", "6", "" };
for (int family_idx = 0; families[family_idx] >= 0; ++family_idx)
{
params->family = families[family_idx];
for (int names_idx = 0; names[names_idx] != NULL; ++names_idx)
{
params->name = names[names_idx];
params->marker = names_marker[names_idx];
run_gbhn_gai (params);
}
}
}
/* Run the test for a specific number of addresses/aliases. */
static void
run_test (int count)
{
write_hosts (count);
struct test_params params =
{
.count = count,
};
support_isolate_in_subprocess (subprocess, ¶ms);
}
static int
do_test (void)
{
support_become_root ();
if (!support_can_chroot ())
return EXIT_UNSUPPORTED;
/* This test should not use gigabytes of memory. */
{
struct rlimit limit;
if (getrlimit (RLIMIT_AS, &limit) != 0)
{
printf ("getrlimit (RLIMIT_AS) failed: %m\n");
return 1;
}
long target = 200 * 1024 * 1024;
if (limit.rlim_cur == RLIM_INFINITY || limit.rlim_cur > target)
{
limit.rlim_cur = target;
if (setrlimit (RLIMIT_AS, &limit) != 0)
{
printf ("setrlimit (RLIMIT_AS) failed: %m\n");
return 1;
}
}
}
__nss_configure_lookup ("hosts", "files");
if (dlopen (LIBNSS_FILES_SO, RTLD_LAZY) == NULL)
FAIL_EXIT1 ("could not load " LIBNSS_DNS_SO ": %s", dlerror ());
/* Run the tests with a few different address/alias counts. */
for (int count = 1; count <= 111; ++count)
run_test (count);
run_test (1111);
run_test (22222);
support_chroot_free (chroot_env);
return 0;
}
#define PREPARE prepare
#include <support/test-driver.c>