1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/* Test __libc_res_nsend buffer mismanagement, basic TCP coverage.
Copyright (C) 2016 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 <errno.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <string.h>
#include <support/check.h>
#include <support/check_nss.h>
#include <support/resolv_test.h>
#include <support/xthread.h>
#include <support/xmemstream.h>
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
static int initial_address_count = 1;
static int subsequent_address_count = 2000;
static int response_number = 0;
static void
response (const struct resolv_response_context *ctx,
struct resolv_response_builder *b,
const char *qname, uint16_t qclass, uint16_t qtype)
{
TEST_VERIFY_EXIT (qname != NULL);
/* If not using TCP, just force its use. */
if (!ctx->tcp)
{
struct resolv_response_flags flags = {.tc = true};
resolv_response_init (b, flags);
resolv_response_add_question (b, qname, qclass, qtype);
return;
}
struct resolv_response_flags flags = {};
resolv_response_init (b, flags);
resolv_response_add_question (b, qname, qclass, qtype);
resolv_response_section (b, ns_s_an);
/* The number of addresses (in the additional section) for the name
server record (in the authoritative section). */
int address_count;
xpthread_mutex_lock (&lock);
++response_number;
if (response_number == 1)
address_count = initial_address_count;
else if (response_number == 2)
{
address_count = 0;
resolv_response_drop (b);
resolv_response_close (b);
}
else
address_count = subsequent_address_count;
xpthread_mutex_unlock (&lock);
/* Only add the address record to the answer section if we requested
any name server addresses. */
if (address_count > 0)
{
resolv_response_open_record (b, qname, qclass, qtype, 0);
switch (qtype)
{
case T_A:
{
char ipv4[4] = {10, response_number >> 8, response_number, 0};
ipv4[3] = 2 * ctx->tcp + 4 * ctx->server_index;
resolv_response_add_data (b, &ipv4, sizeof (ipv4));
}
break;
case T_AAAA:
{
char ipv6[16]
= {0x20, 0x01, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0,
response_number >> 8, response_number, 0, 0};
ipv6[15] = 2 * ctx->tcp + 4 * ctx->server_index;
resolv_response_add_data (b, &ipv6, sizeof (ipv6));
}
break;
default:
support_record_failure ();
printf ("error: unexpected QTYPE: %s/%u/%u\n",
qname, qclass, qtype);
}
resolv_response_close_record (b);
/* Add the name server record. */
resolv_response_section (b, ns_s_ns);
resolv_response_open_record (b, "example", C_IN, T_NS, 0);
resolv_response_add_name (b, "ns.example");
resolv_response_close_record (b);
/* Increase the response size with name server addresses. These
addresses are not copied out of nss_dns, and thus do not
trigger getaddrinfo retries with a larger buffer, making
testing more predictable. */
resolv_response_section (b, ns_s_ar);
for (int i = 1; i <= address_count; ++i)
{
resolv_response_open_record (b, "ns.example", qclass, qtype, 0);
switch (qtype)
{
case T_A:
{
char ipv4[4] = {response_number, i >> 8, i, 0};
ipv4[3] = 2 * ctx->tcp + 4 * ctx->server_index;
resolv_response_add_data (b, &ipv4, sizeof (ipv4));
}
break;
case T_AAAA:
{
char ipv6[16]
= {0x20, 0x01, 0xd, 0xb8, 0, 0, 0, 0, 0, 0,
response_number >> 8, response_number,
i >> 8, i, 0, 0};
ipv6[15] = 2 * ctx->tcp + 4 * ctx->server_index;
resolv_response_add_data (b, &ipv6, sizeof (ipv6));
}
break;
default:
support_record_failure ();
printf ("error: unexpected QTYPE: %s/%u/%u\n",
qname, qclass, qtype);
}
resolv_response_close_record (b);
}
}
}
static char *
expected_result (unsigned port, unsigned response_number)
{
struct xmemstream mem;
xopen_memstream (&mem);
/* We fail the second TCP query to the first server by closing the
connection immediately, without returning any data. This should
cause failover to the second server. */
int server_index = 1;
fprintf (mem.out, "address: STREAM/TCP 10.%u.%u.%u %u\n",
(response_number >> 8) & 0xff, response_number & 0xff,
2 + 4 * server_index, port);
fprintf (mem.out, "address: STREAM/TCP 2001:db8::%x:%x %u\n",
(response_number + 1) & 0xffff,
2 + 4 * server_index, port);
xfclose_memstream (&mem);
return mem.buffer;
}
static void
test_different_sizes (void)
{
struct addrinfo hints =
{
.ai_family = AF_UNSPEC,
.ai_socktype = SOCK_STREAM,
.ai_protocol = IPPROTO_TCP,
};
struct addrinfo *ai;
char *expected;
int ret;
/* This magic number produces a response size close to 2048
bytes. */
initial_address_count = 124;
response_number = 0;
ret = getaddrinfo ("www.example", "80", &hints, &ai);
expected = expected_result (80, 3);
check_addrinfo ("www.example:80", ai, ret, expected);
if (ret == 0)
freeaddrinfo (ai);
free (expected);
response_number = 0;
ret = getaddrinfo ("www123.example", "80", &hints, &ai);
if (ret == 0)
freeaddrinfo (ai);
response_number = 0;
ret = getaddrinfo ("www1234.example", "80", &hints, &ai);
if (ret == 0)
freeaddrinfo (ai);
response_number = 0;
ret = getaddrinfo ("www12345.example", "80", &hints, &ai);
if (ret == 0)
freeaddrinfo (ai);
}
static int
do_test (void)
{
struct resolv_test *obj = resolv_test_start
((struct resolv_redirect_config)
{
.response_callback = response
});
test_different_sizes ();
_res.options |= RES_SNGLKUP;
test_different_sizes ();
_res.options |= RES_SNGLKUPREOP;
test_different_sizes ();
resolv_test_end (obj);
return 0;
}
#include <support/test-driver.c>
|
