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/* Test _nss_dns_getcanonname_r corner cases.
Copyright (C) 2017-2020 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
<https://www.gnu.org/licenses/>. */
#include <dlfcn.h>
#include <errno.h>
#include <gnu/lib-names.h>
#include <netdb.h>
#include <netinet/in.h>
#include <nss.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <support/check.h>
#include <support/resolv_test.h>
#include <support/support.h>
/* _nss_dns_getcanonname_r is not called during regular operation
because nss_dns directly provides a canonical name, so we have to
test it directly. The function pointer is initialized by do_test
below. */
static enum nss_status
(*getcanonname) (const char *name, char *buffer, size_t buflen,
char **result, int *errnop, int *h_errnop);
static void
response (const struct resolv_response_context *ctx,
struct resolv_response_builder *b,
const char *qname, uint16_t qclass, uint16_t qtype)
{
int code;
{
char *tail;
if (sscanf (qname, "code%d.%ms", &code, &tail) != 2
|| strcmp (tail, "example") != 0)
FAIL_EXIT1 ("error: invalid QNAME: %s\n", qname);
free (tail);
}
switch (code)
{
case 1:
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
resolv_response_open_record (b, "www.example", qclass, qtype, 0);
resolv_response_add_data (b, "\xC0\x00\x02\x01", 4);
resolv_response_close_record (b);
break;
case 2:
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
if (qtype == T_AAAA)
{
resolv_response_open_record (b, "www.example", qclass, qtype, 0);
resolv_response_add_data (b, "\xC0\x00\x02\x01", 4);
resolv_response_close_record (b);
for (int i = 0; i < 30000; ++i)
resolv_response_add_data (b, "", 1);
}
break;
case 3:
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
if (qtype == T_AAAA)
{
resolv_response_open_record (b, "www.example", qclass, qtype, 0);
resolv_response_add_data (b, "\xC0\x00\x02\x01", 4);
resolv_response_close_record (b);
}
else
{
for (int i = 0; i < 30000; ++i)
resolv_response_add_data (b, "", 1);
}
break;
case 4:
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
resolv_response_open_record (b, qname, qclass, T_CNAME, 0);
resolv_response_add_name (b, "www.example");
resolv_response_close_record (b);
resolv_response_open_record (b, "www.example", qclass, qtype, 0);
resolv_response_add_data (b, "\xC0\x00\x02\x01", 4);
resolv_response_close_record (b);
break;
case 5:
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
resolv_response_open_record (b, qname, qclass, T_CNAME, 0);
resolv_response_add_name (b, "www.example");
resolv_response_close_record (b);
resolv_response_open_record (b, qname, qclass, T_CNAME, 0);
resolv_response_add_name (b, "www1.example");
resolv_response_close_record (b);
resolv_response_open_record (b, "www1.example", qclass, qtype, 0);
resolv_response_add_data (b, "\xC0\x00\x02\x01", 4);
resolv_response_close_record (b);
break;
case 6:
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
resolv_response_open_record (b, qname, qclass, T_CNAME, 0);
resolv_response_add_name (b, "www.example");
resolv_response_close_record (b);
resolv_response_open_record (b, qname, qclass, 46 /* RRSIG */, 0);
resolv_response_add_name (b, ".");
resolv_response_close_record (b);
resolv_response_open_record (b, "www.example", qclass, qtype, 0);
resolv_response_add_data (b, "\xC0\x00\x02\x01", 4);
resolv_response_close_record (b);
break;
case 102:
if (!ctx->tcp)
{
resolv_response_init (b, (struct resolv_response_flags) {.tc = true});
resolv_response_add_question (b, qname, qclass, qtype);
}
else
{
resolv_response_init
(b, (struct resolv_response_flags) {.ancount = 1});
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
resolv_response_open_record (b, qname, qclass, T_CNAME, 0);
size_t to_fill = 65535 - resolv_response_length (b)
- 2 /* length, "n" */ - 2 /* compression reference */
- 2 /* RR type */;
for (size_t i = 0; i < to_fill; ++i)
resolv_response_add_data (b, "", 1);
resolv_response_close_record (b);
resolv_response_add_name (b, "n.example");
uint16_t rrtype = htons (T_CNAME);
resolv_response_add_data (b, &rrtype, sizeof (rrtype));
}
break;
case 103:
/* NODATA repsonse. */
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
break;
case 104:
resolv_response_init (b, (struct resolv_response_flags) {.ancount = 1});
resolv_response_add_question (b, qname, qclass, qtype);
/* No RR metadata. */
resolv_response_add_name (b, "www.example");
break;
case 105:
if (qtype == T_A)
{
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
/* No data, trigger AAAA query. */
}
else
{
resolv_response_init
(b, (struct resolv_response_flags) {.ancount = 1});
resolv_response_add_question (b, qname, qclass, qtype);
/* No RR metadata. */
resolv_response_add_name
(b, "long-name-exceed-previously-initialized-buffer.example");
}
break;
case 106:
resolv_response_init (b, (struct resolv_response_flags) {.ancount = 1});
resolv_response_add_question (b, qname, qclass, qtype);
/* No RR metadata. */
resolv_response_add_name (b, "www.example");
resolv_response_add_data (b, "\xff\xff", 2);
break;
case 107:
if (qtype == T_A)
{
resolv_response_init (b, (struct resolv_response_flags) {});
resolv_response_add_question (b, qname, qclass, qtype);
/* No data, trigger AAAA query. */
}
else
{
resolv_response_init
(b, (struct resolv_response_flags) {.ancount = 1});
resolv_response_add_question (b, qname, qclass, qtype);
/* No RR metadata. */
resolv_response_add_name (b, "www.example");
resolv_response_add_data (b, "\xff\xff", 2);
}
break;
default:
FAIL_EXIT1 ("error: invalid QNAME: %s (code %d)\n", qname, code);
}
}
static void
check (int code, const char *expected)
{
char qname[200];
snprintf (qname, sizeof (qname), "code%d.example", code);
char *result;
enum nss_status status;
{
enum { buffer_size = 4096 };
char *buffer = xmalloc (buffer_size);
char *temp_result;
int temp_errno;
int temp_herrno;
status = getcanonname
(qname, buffer, buffer_size, &temp_result, &temp_errno, &temp_herrno);
if (status == NSS_STATUS_SUCCESS)
result = xstrdup (temp_result);
else
{
errno = temp_errno;
h_errno = temp_herrno;
}
free (buffer);
}
if (status == NSS_STATUS_SUCCESS)
{
if (expected != NULL)
{
if (strcmp (result, expected) != 0)
{
support_record_failure ();
printf ("error: getcanonname (%s) failed\n", qname);
printf ("error: expected: %s\n", expected);
printf ("error: actual: %s\n", result);
free (result);
return;
}
}
else
{
support_record_failure ();
printf ("error: getcanonname (%s) unexpected success\n", qname);
printf ("error: actual: %s\n", result);
free (result);
return;
}
free (result);
}
else
{
if (expected != NULL)
{
support_record_failure ();
printf ("error: getcanonname (%s) failed\n", qname);
printf ("error: expected: %s\n", expected);
return;
}
}
}
static int
do_test (void)
{
void *nss_dns_handle = dlopen (LIBNSS_DNS_SO, RTLD_LAZY);
if (nss_dns_handle == NULL)
FAIL_EXIT1 ("could not dlopen %s: %s", LIBNSS_DNS_SO, dlerror ());
{
const char *func = "_nss_dns_getcanonname_r";
void *ptr = dlsym (nss_dns_handle, func);
if (ptr == NULL)
FAIL_EXIT1 ("could not look up %s: %s", func, dlerror ());
getcanonname = ptr;
}
struct resolv_test *aux = resolv_test_start
((struct resolv_redirect_config)
{
.response_callback = response,
});
check (1, "www.example");
check (2, "www.example");
check (3, "www.example");
check (4, "www.example");
check (5, "www1.example");
/* This should really result in "www.example", but the fake RRSIG
record causes the current implementation to stop parsing. */
check (6, NULL);
for (int i = 102; i <= 107; ++i)
check (i, NULL);
resolv_test_end (aux);
TEST_VERIFY (dlclose (nss_dns_handle) == 0);
return 0;
}
#include <support/test-driver.c>
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