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/* Tests for resource record parsing.
Copyright (C) 2022-2025 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 <arpa/nameser.h>
#include <string.h>
#include <support/check.h>
#include <support/next_to_fault.h>
/* Reference packet for packet parsing. */
static const unsigned char valid_packet[] =
{ 0x11, 0x12, 0x13, 0x14,
0x00, 0x01, /* Question count. */
0x00, 0x02, /* Answer count. */
0x21, 0x22, 0x23, 0x24, /* Other counts (not actually in packet). */
3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0,
0x00, 0x1c, /* Question type: AAAA. */
0x00, 0x01, /* Question class: IN. */
0xc0, 0x0c, /* Compression reference to QNAME. */
0x00, 0x1c, /* Record type: AAAA. */
0x00, 0x01, /* Record class: IN. */
0x12, 0x34, 0x56, 0x78, /* Record TTL. */
0x00, 0x10, /* Record data length (16 bytes). */
0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* IPv6 address. */
0xc0, 0x0c, /* Compression reference to QNAME. */
0x00, 0x1c, /* Record type: AAAA. */
0x00, 0x01, /* Record class: IN. */
0x11, 0x33, 0x55, 0x77, /* Record TTL. */
0x00, 0x10, /* Record data length (16 bytes). */
0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* IPv6 address. */
};
/* Special offsets in valid_packet. */
enum
{
offset_of_first_record = 29,
offset_of_second_record = 57,
};
/* Check that parsing valid_packet succeeds. */
static void
test_valid (void)
{
struct ns_rr_cursor c;
TEST_VERIFY_EXIT (__ns_rr_cursor_init (&c, valid_packet,
sizeof (valid_packet)));
TEST_COMPARE (ns_rr_cursor_rcode (&c), 4);
TEST_COMPARE (ns_rr_cursor_ancount (&c), 2);
TEST_COMPARE (ns_rr_cursor_nscount (&c), 0x2122);
TEST_COMPARE (ns_rr_cursor_adcount (&c), 0x2324);
TEST_COMPARE_BLOB (ns_rr_cursor_qname (&c), 13, &valid_packet[12], 13);
TEST_COMPARE (ns_rr_cursor_qtype (&c), T_AAAA);
TEST_COMPARE (ns_rr_cursor_qclass (&c), C_IN);
TEST_COMPARE (c.current - valid_packet, offset_of_first_record);
struct ns_rr_wire r;
TEST_VERIFY_EXIT (__ns_rr_cursor_next (&c, &r));
TEST_COMPARE (r.rtype, T_AAAA);
TEST_COMPARE (r.rclass, C_IN);
TEST_COMPARE (r.ttl, 0x12345678);
TEST_COMPARE_BLOB (r.rdata, r.rdlength,
"\x90\x91\x92\x93\x94\x95\x96\x97"
"\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f", 16);
TEST_COMPARE (c.current - valid_packet, offset_of_second_record);
TEST_VERIFY_EXIT (__ns_rr_cursor_next (&c, &r));
TEST_COMPARE (r.rtype, T_AAAA);
TEST_COMPARE (r.rclass, C_IN);
TEST_COMPARE (r.ttl, 0x11335577);
TEST_COMPARE_BLOB (r.rdata, r.rdlength,
"\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7"
"\xa8\xa9\xaa\xab\xac\xad\xae\xaf", 16);
TEST_VERIFY (c.current == c.end);
}
/* Check that trying to parse a packet with a compressed QNAME fails. */
static void
test_compressed_qname (void)
{
static const unsigned char packet[] =
{ 0x11, 0x12, 0x13, 0x14,
0x00, 0x01, /* Question count. */
0x00, 0x00, /* Answer count. */
0x00, 0x00, 0x00, 0x00, /* Other counts. */
3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0xc0, 0x04,
0x00, 0x01, /* Question type: A. */
0x00, 0x01, /* Question class: IN. */
};
struct ns_rr_cursor c;
TEST_VERIFY_EXIT (!__ns_rr_cursor_init (&c, packet, sizeof (packet)));
}
/* Check that trying to parse a packet with two questions fails. */
static void
test_two_questions (void)
{
static const unsigned char packet[] =
{ 0x11, 0x12, 0x13, 0x14,
0x00, 0x02, /* Question count. */
0x00, 0x00, /* Answer count. */
0x00, 0x00, 0x00, 0x00, /* Other counts. */
3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0xc0, 0x04,
0x00, 0x01, /* Question type: A. */
0x00, 0x01, /* Question class: IN. */
3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0xc0, 0x04,
0x00, 0x1c, /* Question type: AAAA. */
0x00, 0x01, /* Question class: IN. */
};
struct ns_rr_cursor c;
TEST_VERIFY_EXIT (!__ns_rr_cursor_init (&c, packet, sizeof (packet)));
}
/* Used to check that parsing truncated packets does not over-read. */
static struct support_next_to_fault ntf;
/* Truncated packet in the second resource record. */
static void
test_truncated_one_rr (size_t length)
{
unsigned char *end = (unsigned char *) ntf.buffer - ntf.length;
unsigned char *start = end - length;
/* Produce the truncated packet. */
memcpy (start, valid_packet, length);
struct ns_rr_cursor c;
TEST_VERIFY_EXIT (__ns_rr_cursor_init (&c, start, length));
TEST_COMPARE (ns_rr_cursor_rcode (&c), 4);
TEST_COMPARE (ns_rr_cursor_ancount (&c), 2);
TEST_COMPARE (ns_rr_cursor_nscount (&c), 0x2122);
TEST_COMPARE (ns_rr_cursor_adcount (&c), 0x2324);
TEST_COMPARE_BLOB (ns_rr_cursor_qname (&c), 13, &valid_packet[12], 13);
TEST_COMPARE (ns_rr_cursor_qtype (&c), T_AAAA);
TEST_COMPARE (ns_rr_cursor_qclass (&c), C_IN);
TEST_COMPARE (c.current - start, offset_of_first_record);
struct ns_rr_wire r;
TEST_VERIFY_EXIT (__ns_rr_cursor_next (&c, &r));
TEST_COMPARE (r.rtype, T_AAAA);
TEST_COMPARE (r.rclass, C_IN);
TEST_COMPARE (r.ttl, 0x12345678);
TEST_COMPARE_BLOB (r.rdata, r.rdlength,
"\x90\x91\x92\x93\x94\x95\x96\x97"
"\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f", 16);
TEST_COMPARE (c.current - start, offset_of_second_record);
TEST_VERIFY (!__ns_rr_cursor_next (&c, &r));
}
/* Truncated packet in the first resource record. */
static void
test_truncated_no_rr (size_t length)
{
unsigned char *end = (unsigned char *) ntf.buffer - ntf.length;
unsigned char *start = end - length;
/* Produce the truncated packet. */
memcpy (start, valid_packet, length);
struct ns_rr_cursor c;
TEST_VERIFY_EXIT (__ns_rr_cursor_init (&c, start, length));
TEST_COMPARE (ns_rr_cursor_rcode (&c), 4);
TEST_COMPARE (ns_rr_cursor_ancount (&c), 2);
TEST_COMPARE (ns_rr_cursor_nscount (&c), 0x2122);
TEST_COMPARE (ns_rr_cursor_adcount (&c), 0x2324);
TEST_COMPARE_BLOB (ns_rr_cursor_qname (&c), 13, &valid_packet[12], 13);
TEST_COMPARE (ns_rr_cursor_qtype (&c), T_AAAA);
TEST_COMPARE (ns_rr_cursor_qclass (&c), C_IN);
TEST_COMPARE (c.current - start, offset_of_first_record);
struct ns_rr_wire r;
TEST_VERIFY (!__ns_rr_cursor_next (&c, &r));
}
/* Truncated packet before first resource record. */
static void
test_truncated_before_rr (size_t length)
{
unsigned char *end = (unsigned char *) ntf.buffer - ntf.length;
unsigned char *start = end - length;
/* Produce the truncated packet. */
memcpy (start, valid_packet, length);
struct ns_rr_cursor c;
TEST_VERIFY_EXIT (!__ns_rr_cursor_init (&c, start, length));
}
static int
do_test (void)
{
ntf = support_next_to_fault_allocate (sizeof (valid_packet));
test_valid ();
test_compressed_qname ();
test_two_questions ();
for (int length = offset_of_second_record; length < sizeof (valid_packet);
++length)
test_truncated_one_rr (length);
for (int length = offset_of_first_record; length < offset_of_second_record;
++length)
test_truncated_no_rr (length);
for (int length = 0; length < offset_of_first_record; ++length)
test_truncated_before_rr (length);
support_next_to_fault_free (&ntf);
return 0;
}
#include <support/test-driver.c>
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