1 | /* Tests for resource record parsing. |
2 | Copyright (C) 2022-2024 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <arpa/nameser.h> |
20 | #include <string.h> |
21 | #include <support/check.h> |
22 | #include <support/next_to_fault.h> |
23 | |
24 | /* Reference packet for packet parsing. */ |
25 | static const unsigned char valid_packet[] = |
26 | { 0x11, 0x12, 0x13, 0x14, |
27 | 0x00, 0x01, /* Question count. */ |
28 | 0x00, 0x02, /* Answer count. */ |
29 | 0x21, 0x22, 0x23, 0x24, /* Other counts (not actually in packet). */ |
30 | 3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0, |
31 | 0x00, 0x1c, /* Question type: AAAA. */ |
32 | 0x00, 0x01, /* Question class: IN. */ |
33 | 0xc0, 0x0c, /* Compression reference to QNAME. */ |
34 | 0x00, 0x1c, /* Record type: AAAA. */ |
35 | 0x00, 0x01, /* Record class: IN. */ |
36 | 0x12, 0x34, 0x56, 0x78, /* Record TTL. */ |
37 | 0x00, 0x10, /* Record data length (16 bytes). */ |
38 | 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, |
39 | 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* IPv6 address. */ |
40 | 0xc0, 0x0c, /* Compression reference to QNAME. */ |
41 | 0x00, 0x1c, /* Record type: AAAA. */ |
42 | 0x00, 0x01, /* Record class: IN. */ |
43 | 0x11, 0x33, 0x55, 0x77, /* Record TTL. */ |
44 | 0x00, 0x10, /* Record data length (16 bytes). */ |
45 | 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, |
46 | 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* IPv6 address. */ |
47 | }; |
48 | |
49 | /* Special offsets in valid_packet. */ |
50 | enum |
51 | { |
52 | offset_of_first_record = 29, |
53 | offset_of_second_record = 57, |
54 | }; |
55 | |
56 | /* Check that parsing valid_packet succeeds. */ |
57 | static void |
58 | test_valid (void) |
59 | { |
60 | struct ns_rr_cursor c; |
61 | TEST_VERIFY_EXIT (__ns_rr_cursor_init (&c, valid_packet, |
62 | sizeof (valid_packet))); |
63 | TEST_COMPARE (ns_rr_cursor_rcode (&c), 4); |
64 | TEST_COMPARE (ns_rr_cursor_ancount (&c), 2); |
65 | TEST_COMPARE (ns_rr_cursor_nscount (&c), 0x2122); |
66 | TEST_COMPARE (ns_rr_cursor_adcount (&c), 0x2324); |
67 | TEST_COMPARE_BLOB (ns_rr_cursor_qname (&c), 13, &valid_packet[12], 13); |
68 | TEST_COMPARE (ns_rr_cursor_qtype (&c), T_AAAA); |
69 | TEST_COMPARE (ns_rr_cursor_qclass (&c), C_IN); |
70 | TEST_COMPARE (c.current - valid_packet, offset_of_first_record); |
71 | |
72 | struct ns_rr_wire r; |
73 | TEST_VERIFY_EXIT (__ns_rr_cursor_next (&c, &r)); |
74 | TEST_COMPARE (r.rtype, T_AAAA); |
75 | TEST_COMPARE (r.rclass, C_IN); |
76 | TEST_COMPARE (r.ttl, 0x12345678); |
77 | TEST_COMPARE_BLOB (r.rdata, r.rdlength, |
78 | "\x90\x91\x92\x93\x94\x95\x96\x97" |
79 | "\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f" , 16); |
80 | TEST_COMPARE (c.current - valid_packet, offset_of_second_record); |
81 | TEST_VERIFY_EXIT (__ns_rr_cursor_next (&c, &r)); |
82 | TEST_COMPARE (r.rtype, T_AAAA); |
83 | TEST_COMPARE (r.rclass, C_IN); |
84 | TEST_COMPARE (r.ttl, 0x11335577); |
85 | TEST_COMPARE_BLOB (r.rdata, r.rdlength, |
86 | "\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7" |
87 | "\xa8\xa9\xaa\xab\xac\xad\xae\xaf" , 16); |
88 | TEST_VERIFY (c.current == c.end); |
89 | } |
90 | |
91 | /* Check that trying to parse a packet with a compressed QNAME fails. */ |
92 | static void |
93 | test_compressed_qname (void) |
94 | { |
95 | static const unsigned char packet[] = |
96 | { 0x11, 0x12, 0x13, 0x14, |
97 | 0x00, 0x01, /* Question count. */ |
98 | 0x00, 0x00, /* Answer count. */ |
99 | 0x00, 0x00, 0x00, 0x00, /* Other counts. */ |
100 | 3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0xc0, 0x04, |
101 | 0x00, 0x01, /* Question type: A. */ |
102 | 0x00, 0x01, /* Question class: IN. */ |
103 | }; |
104 | |
105 | struct ns_rr_cursor c; |
106 | TEST_VERIFY_EXIT (!__ns_rr_cursor_init (&c, packet, sizeof (packet))); |
107 | } |
108 | |
109 | /* Check that trying to parse a packet with two questions fails. */ |
110 | static void |
111 | test_two_questions (void) |
112 | { |
113 | static const unsigned char packet[] = |
114 | { 0x11, 0x12, 0x13, 0x14, |
115 | 0x00, 0x02, /* Question count. */ |
116 | 0x00, 0x00, /* Answer count. */ |
117 | 0x00, 0x00, 0x00, 0x00, /* Other counts. */ |
118 | 3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0xc0, 0x04, |
119 | 0x00, 0x01, /* Question type: A. */ |
120 | 0x00, 0x01, /* Question class: IN. */ |
121 | 3, 'w', 'w', 'w', 7, 'e', 'x', 'a', 'm', 'p', 'l', 'e', 0xc0, 0x04, |
122 | 0x00, 0x1c, /* Question type: AAAA. */ |
123 | 0x00, 0x01, /* Question class: IN. */ |
124 | }; |
125 | |
126 | struct ns_rr_cursor c; |
127 | TEST_VERIFY_EXIT (!__ns_rr_cursor_init (&c, packet, sizeof (packet))); |
128 | } |
129 | |
130 | /* Used to check that parsing truncated packets does not over-read. */ |
131 | static struct support_next_to_fault ntf; |
132 | |
133 | /* Truncated packet in the second resource record. */ |
134 | static void |
135 | test_truncated_one_rr (size_t length) |
136 | { |
137 | unsigned char *end = (unsigned char *) ntf.buffer - ntf.length; |
138 | unsigned char *start = end - length; |
139 | |
140 | /* Produce the truncated packet. */ |
141 | memcpy (dest: start, src: valid_packet, n: length); |
142 | |
143 | struct ns_rr_cursor c; |
144 | TEST_VERIFY_EXIT (__ns_rr_cursor_init (&c, start, length)); |
145 | TEST_COMPARE (ns_rr_cursor_rcode (&c), 4); |
146 | TEST_COMPARE (ns_rr_cursor_ancount (&c), 2); |
147 | TEST_COMPARE (ns_rr_cursor_nscount (&c), 0x2122); |
148 | TEST_COMPARE (ns_rr_cursor_adcount (&c), 0x2324); |
149 | TEST_COMPARE_BLOB (ns_rr_cursor_qname (&c), 13, &valid_packet[12], 13); |
150 | TEST_COMPARE (ns_rr_cursor_qtype (&c), T_AAAA); |
151 | TEST_COMPARE (ns_rr_cursor_qclass (&c), C_IN); |
152 | TEST_COMPARE (c.current - start, offset_of_first_record); |
153 | |
154 | struct ns_rr_wire r; |
155 | TEST_VERIFY_EXIT (__ns_rr_cursor_next (&c, &r)); |
156 | TEST_COMPARE (r.rtype, T_AAAA); |
157 | TEST_COMPARE (r.rclass, C_IN); |
158 | TEST_COMPARE (r.ttl, 0x12345678); |
159 | TEST_COMPARE_BLOB (r.rdata, r.rdlength, |
160 | "\x90\x91\x92\x93\x94\x95\x96\x97" |
161 | "\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f" , 16); |
162 | TEST_COMPARE (c.current - start, offset_of_second_record); |
163 | TEST_VERIFY (!__ns_rr_cursor_next (&c, &r)); |
164 | } |
165 | |
166 | /* Truncated packet in the first resource record. */ |
167 | static void |
168 | test_truncated_no_rr (size_t length) |
169 | { |
170 | unsigned char *end = (unsigned char *) ntf.buffer - ntf.length; |
171 | unsigned char *start = end - length; |
172 | |
173 | /* Produce the truncated packet. */ |
174 | memcpy (dest: start, src: valid_packet, n: length); |
175 | |
176 | struct ns_rr_cursor c; |
177 | TEST_VERIFY_EXIT (__ns_rr_cursor_init (&c, start, length)); |
178 | TEST_COMPARE (ns_rr_cursor_rcode (&c), 4); |
179 | TEST_COMPARE (ns_rr_cursor_ancount (&c), 2); |
180 | TEST_COMPARE (ns_rr_cursor_nscount (&c), 0x2122); |
181 | TEST_COMPARE (ns_rr_cursor_adcount (&c), 0x2324); |
182 | TEST_COMPARE_BLOB (ns_rr_cursor_qname (&c), 13, &valid_packet[12], 13); |
183 | TEST_COMPARE (ns_rr_cursor_qtype (&c), T_AAAA); |
184 | TEST_COMPARE (ns_rr_cursor_qclass (&c), C_IN); |
185 | TEST_COMPARE (c.current - start, offset_of_first_record); |
186 | |
187 | struct ns_rr_wire r; |
188 | TEST_VERIFY (!__ns_rr_cursor_next (&c, &r)); |
189 | } |
190 | |
191 | /* Truncated packet before first resource record. */ |
192 | static void |
193 | test_truncated_before_rr (size_t length) |
194 | { |
195 | unsigned char *end = (unsigned char *) ntf.buffer - ntf.length; |
196 | unsigned char *start = end - length; |
197 | |
198 | /* Produce the truncated packet. */ |
199 | memcpy (dest: start, src: valid_packet, n: length); |
200 | |
201 | struct ns_rr_cursor c; |
202 | TEST_VERIFY_EXIT (!__ns_rr_cursor_init (&c, start, length)); |
203 | } |
204 | |
205 | static int |
206 | do_test (void) |
207 | { |
208 | ntf = support_next_to_fault_allocate (size: sizeof (valid_packet)); |
209 | |
210 | test_valid (); |
211 | test_compressed_qname (); |
212 | test_two_questions (); |
213 | |
214 | for (int length = offset_of_second_record; length < sizeof (valid_packet); |
215 | ++length) |
216 | test_truncated_one_rr (length); |
217 | for (int length = offset_of_first_record; length < offset_of_second_record; |
218 | ++length) |
219 | test_truncated_no_rr (length); |
220 | for (int length = 0; length < offset_of_first_record; ++length) |
221 | test_truncated_before_rr (length); |
222 | |
223 | support_next_to_fault_free (&ntf); |
224 | return 0; |
225 | } |
226 | |
227 | #include <support/test-driver.c> |
228 | |