#include <netdb.h>
#include <resolv/resolv-internal.h>
#include <scratch_buffer.h>
+#include <alloc_buffer.h>
/* Get implementation for some internal functions. */
}, const void *addr, socklen_t len, int af)
#undef EXTRA_ARGS_VALUE
+/* Type of the address and alias arrays. */
+#define DYNARRAY_STRUCT array
+#define DYNARRAY_ELEMENT char *
+#define DYNARRAY_PREFIX array_
+#include <malloc/dynarray-skeleton.c>
+
static enum nss_status
gethostbyname3_multi (FILE * stream, const char *name, int af,
struct hostent *result, char *buffer, size_t buflen,
int *errnop, int *herrnop, int flags)
{
+ assert (af == AF_INET || af == AF_INET6);
+
/* We have to get all host entries from the file. */
struct scratch_buffer tmp_buffer;
scratch_buffer_init (&tmp_buffer);
struct hostent tmp_result_buf;
- int naddrs = 1;
- int naliases = 0;
- char *bufferend;
+ struct array addresses;
+ array_init (&addresses);
+ struct array aliases;
+ array_init (&aliases);
enum nss_status status;
- while (result->h_aliases[naliases] != NULL)
- ++naliases;
-
- bufferend = (char *) &result->h_aliases[naliases + 1];
+ /* Preserve the addresses and aliases encountered so far. */
+ for (size_t i = 0; result->h_addr_list[i] != NULL; ++i)
+ array_add (&addresses, result->h_addr_list[i]);
+ for (size_t i = 0; result->h_aliases[i] != NULL; ++i)
+ array_add (&aliases, result->h_aliases[i]);
+
+ /* The output buffer re-uses now-unused space at the end of the
+ buffer, starting with the aliases array. It comes last in the
+ data produced by internal_getent. (The alias names themselves
+ are still located in the line read in internal_getent, which is
+ stored at the beginning of the buffer.) */
+ struct alloc_buffer outbuf;
+ {
+ char *bufferend = (char *) result->h_aliases;
+ outbuf = alloc_buffer_create (bufferend, buffer + buflen - bufferend);
+ }
while (true)
{
}
while ((matches = 0));
+ /* If the line matches, we need to copy the addresses and
+ aliases, so that we can reuse tmp_buffer for the next
+ line. */
if (matches)
{
- /* We could be very clever and try to recycle a few bytes
- in the buffer instead of generating new arrays. But
- we are not doing this here since it's more work than
- it's worth. Simply let the user provide a bit bigger
- buffer. */
- char **new_h_addr_list;
- char **new_h_aliases;
- int newaliases = 0;
- size_t newstrlen = 0;
- int cnt;
-
- /* Count the new aliases and the length of the strings. */
- while (tmp_result_buf.h_aliases[newaliases] != NULL)
+ /* Record the addresses. */
+ for (size_t i = 0; tmp_result_buf.h_addr_list[i] != NULL; ++i)
{
- char *cp = tmp_result_buf.h_aliases[newaliases];
- ++newaliases;
- newstrlen += strlen (cp) + 1;
+ /* Allocate the target space in the output buffer,
+ depending on the address family. */
+ void *target;
+ if (af == AF_INET)
+ {
+ assert (tmp_result_buf.h_length == 4);
+ target = alloc_buffer_alloc (&outbuf, struct in_addr);
+ }
+ else if (af == AF_INET6)
+ {
+ assert (tmp_result_buf.h_length == 16);
+ target = alloc_buffer_alloc (&outbuf, struct in6_addr);
+ }
+ else
+ __builtin_unreachable ();
+
+ if (target == NULL)
+ {
+ /* Request a larger output buffer. */
+ *errnop = ERANGE;
+ *herrnop = NETDB_INTERNAL;
+ status = NSS_STATUS_TRYAGAIN;
+ break;
+ }
+ memcpy (target, tmp_result_buf.h_addr_list[i],
+ tmp_result_buf.h_length);
+ array_add (&addresses, target);
}
- /* If the real name is different add it also to the
- aliases. This means that there is a duplication
- in the alias list but this is really the user's
- problem. */
- if (strcmp (old_result->h_name,
- tmp_result_buf.h_name) != 0)
+
+ /* Record the aliases. */
+ for (size_t i = 0; tmp_result_buf.h_aliases[i] != NULL; ++i)
{
- ++newaliases;
- newstrlen += strlen (tmp_result_buf.h_name) + 1;
+ char *alias = tmp_result_buf.h_aliases[i];
+ array_add (&aliases,
+ alloc_buffer_copy_string (&outbuf, alias));
}
- /* Make sure bufferend is aligned. */
- assert ((bufferend - (char *) 0) % sizeof (char *) == 0);
-
- /* Now we can check whether the buffer is large enough.
- 16 is the maximal size of the IP address. */
- if (bufferend + 16 + (naddrs + 2) * sizeof (char *)
- + roundup (newstrlen, sizeof (char *))
- + (naliases + newaliases + 1) * sizeof (char *)
- >= buffer + buflen)
+ /* If the real name is different add, it also to the
+ aliases. This means that there is a duplication in
+ the alias list but this is really the user's
+ problem. */
+ {
+ char *new_name = tmp_result_buf.h_name;
+ if (strcmp (old_result->h_name, new_name) != 0)
+ array_add (&aliases,
+ alloc_buffer_copy_string (&outbuf, new_name));
+ }
+
+ /* Report memory allocation failures during the
+ expansion of the temporary arrays. */
+ if (array_has_failed (&addresses) || array_has_failed (&aliases))
{
- *errnop = ERANGE;
+ *errnop = ENOMEM;
*herrnop = NETDB_INTERNAL;
- status = NSS_STATUS_TRYAGAIN;
+ status = NSS_STATUS_UNAVAIL;
break;
}
- new_h_addr_list =
- (char **) (bufferend
- + roundup (newstrlen, sizeof (char *))
- + 16);
- new_h_aliases =
- (char **) ((char *) new_h_addr_list
- + (naddrs + 2) * sizeof (char *));
-
- /* Copy the old data in the new arrays. */
- for (cnt = 0; cnt < naddrs; ++cnt)
- new_h_addr_list[cnt] = old_result->h_addr_list[cnt];
-
- for (cnt = 0; cnt < naliases; ++cnt)
- new_h_aliases[cnt] = old_result->h_aliases[cnt];
-
- /* Store the new strings. */
- cnt = 0;
- while (tmp_result_buf.h_aliases[cnt] != NULL)
+ /* Request a larger output buffer if we ran out of room. */
+ if (alloc_buffer_has_failed (&outbuf))
{
- new_h_aliases[naliases++] = bufferend;
- bufferend = (__stpcpy (bufferend,
- tmp_result_buf.h_aliases[cnt])
- + 1);
- ++cnt;
- }
-
- if (cnt < newaliases)
- {
- new_h_aliases[naliases++] = bufferend;
- bufferend = __stpcpy (bufferend,
- tmp_result_buf.h_name) + 1;
+ *errnop = ERANGE;
+ *herrnop = NETDB_INTERNAL;
+ status = NSS_STATUS_TRYAGAIN;
+ break;
}
- /* Final NULL pointer. */
- new_h_aliases[naliases] = NULL;
-
- /* Round up the buffer end address. */
- bufferend += (sizeof (char *)
- - ((bufferend - (char *) 0)
- % sizeof (char *))) % sizeof (char *);
-
- /* Now the new address. */
- new_h_addr_list[naddrs++] =
- memcpy (bufferend, tmp_result_buf.h_addr,
- tmp_result_buf.h_length);
-
- /* Also here a final NULL pointer. */
- new_h_addr_list[naddrs] = NULL;
-
- /* Store the new array pointers. */
- old_result->h_aliases = new_h_aliases;
- old_result->h_addr_list = new_h_addr_list;
-
- /* Compute the new buffer end. */
- bufferend = (char *) &new_h_aliases[naliases + 1];
- assert (bufferend <= buffer + buflen);
-
result = old_result;
} /* If match was found. */
if (status != NSS_STATUS_TRYAGAIN)
status = NSS_STATUS_SUCCESS;
+ if (status == NSS_STATUS_SUCCESS)
+ {
+ /* Copy the address and alias arrays into the output buffer and
+ add NULL terminators. The pointed-to elements were directly
+ written into the output buffer above and do not need to be
+ copied again. */
+ size_t addresses_count = array_size (&addresses);
+ size_t aliases_count = array_size (&aliases);
+ char **out_addresses = alloc_buffer_alloc_array
+ (&outbuf, char *, addresses_count + 1);
+ char **out_aliases = alloc_buffer_alloc_array
+ (&outbuf, char *, aliases_count + 1);
+ if (out_addresses == NULL || out_aliases == NULL)
+ {
+ /* The output buffer is not large enough. */
+ *errnop = ERANGE;
+ *herrnop = NETDB_INTERNAL;
+ status = NSS_STATUS_TRYAGAIN;
+ /* Fall through to function exit. */
+ }
+ else
+ {
+ /* Everything is allocated in place. Make the copies and
+ adjust the array pointers. */
+ memcpy (out_addresses, array_begin (&addresses),
+ addresses_count * sizeof (char *));
+ out_addresses[addresses_count] = NULL;
+ memcpy (out_aliases, array_begin (&aliases),
+ aliases_count * sizeof (char *));
+ out_aliases[aliases_count] = NULL;
+
+ result->h_addr_list = out_addresses;
+ result->h_aliases = out_aliases;
+
+ status = NSS_STATUS_SUCCESS;
+ }
+ }
+
scratch_buffer_free (&tmp_buffer);
+ array_free (&addresses);
+ array_free (&aliases);
return status;
}
--- /dev/null
+/* Parse /etc/hosts in multi mode with many addresses/aliases.
+ 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/>. */
+
+#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>
projects / thirdparty / glibc.git / commitdiff
