1 /* Exercise low-level query functions with different QTYPEs.
2    Copyright (C) 2016-2022 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 <resolv.h>
20 #include <string.h>
21 #include <support/check.h>
22 #include <support/check_nss.h>
23 #include <support/resolv_test.h>
24 #include <support/support.h>
25 #include <support/test-driver.h>
26 #include <support/xmemstream.h>
27 
28 /* If ture, the response function will send the actual response packet
29    over TCP instead of UDP.  */
30 static volatile bool force_tcp;
31 
32 /* Send back a fake resource record matching the QTYPE.  */
33 static void
response(const struct resolv_response_context * ctx,struct resolv_response_builder * b,const char * qname,uint16_t qclass,uint16_t qtype)34 response (const struct resolv_response_context *ctx,
35           struct resolv_response_builder *b,
36           const char *qname, uint16_t qclass, uint16_t qtype)
37 {
38   if (force_tcp && ctx->tcp)
39     {
40       resolv_response_init (b, (struct resolv_response_flags) { .tc = 1 });
41       resolv_response_add_question (b, qname, qclass, qtype);
42       return;
43     }
44 
45   resolv_response_init (b, (struct resolv_response_flags) { });
46   resolv_response_add_question (b, qname, qclass, qtype);
47   resolv_response_section (b, ns_s_an);
48   resolv_response_open_record (b, qname, qclass, qtype, 0);
49   resolv_response_add_data (b, &qtype, sizeof (qtype));
50   resolv_response_close_record (b);
51 }
52 
53 static const char domain[] = "www.example.com";
54 
55 static int
wrap_res_query(int type,unsigned char * answer,int answer_length)56 wrap_res_query (int type, unsigned char *answer, int answer_length)
57 {
58   return res_query (domain, C_IN, type, answer, answer_length);
59 }
60 
61 static int
wrap_res_search(int type,unsigned char * answer,int answer_length)62 wrap_res_search (int type, unsigned char *answer, int answer_length)
63 {
64   return res_query (domain, C_IN, type, answer, answer_length);
65 }
66 
67 static int
wrap_res_querydomain(int type,unsigned char * answer,int answer_length)68 wrap_res_querydomain (int type, unsigned char *answer, int answer_length)
69 {
70   return res_querydomain ("www", "example.com", C_IN, type,
71                            answer, answer_length);
72 }
73 
74 static int
wrap_res_send(int type,unsigned char * answer,int answer_length)75 wrap_res_send (int type, unsigned char *answer, int answer_length)
76 {
77   unsigned char buf[512];
78   int ret = res_mkquery (QUERY, domain, C_IN, type,
79                          (const unsigned char *) "", 0, NULL,
80                          buf, sizeof (buf));
81   if (type < 0 || type >= 65536)
82     {
83       /* res_mkquery fails for out-of-range record types.  */
84       TEST_VERIFY_EXIT (ret == -1);
85       return -1;
86     }
87   TEST_VERIFY_EXIT (ret > 12);  /* DNS header length.  */
88   return res_send (buf, ret, answer, answer_length);
89 }
90 
91 static int
wrap_res_nquery(int type,unsigned char * answer,int answer_length)92 wrap_res_nquery (int type, unsigned char *answer, int answer_length)
93 {
94   return res_nquery (&_res, domain, C_IN, type, answer, answer_length);
95 }
96 
97 static int
wrap_res_nsearch(int type,unsigned char * answer,int answer_length)98 wrap_res_nsearch (int type, unsigned char *answer, int answer_length)
99 {
100   return res_nquery (&_res, domain, C_IN, type, answer, answer_length);
101 }
102 
103 static int
wrap_res_nquerydomain(int type,unsigned char * answer,int answer_length)104 wrap_res_nquerydomain (int type, unsigned char *answer, int answer_length)
105 {
106   return res_nquerydomain (&_res, "www", "example.com", C_IN, type,
107                            answer, answer_length);
108 }
109 
110 static int
wrap_res_nsend(int type,unsigned char * answer,int answer_length)111 wrap_res_nsend (int type, unsigned char *answer, int answer_length)
112 {
113   unsigned char buf[512];
114   int ret = res_nmkquery (&_res, QUERY, domain, C_IN, type,
115                          (const unsigned char *) "", 0, NULL,
116                          buf, sizeof (buf));
117   if (type < 0 || type >= 65536)
118     {
119       /* res_mkquery fails for out-of-range record types.  */
120       TEST_VERIFY_EXIT (ret == -1);
121       return -1;
122     }
123   TEST_VERIFY_EXIT (ret > 12);  /* DNS header length.  */
124   return res_nsend (&_res, buf, ret, answer, answer_length);
125 }
126 
127 static void
test_function(const char * fname,int (* func)(int type,unsigned char * answer,int answer_length))128 test_function (const char *fname,
129                int (*func) (int type,
130                             unsigned char *answer, int answer_length))
131 {
132   unsigned char buf[512];
133   for (int tcp = 0; tcp < 2; ++tcp)
134     {
135       force_tcp = tcp;
136       for (unsigned int type = 1; type <= 65535; ++type)
137         {
138           if (test_verbose)
139             printf ("info: sending QTYPE %d with %s (tcp=%d)\n",
140                     type, fname, tcp);
141           int ret = func (type, buf, sizeof (buf));
142           if (ret != 47)
143             FAIL_EXIT1 ("%s tcp=%d qtype=%d return value %d",
144                         fname,tcp, type, ret);
145           /* One question, one answer record.  */
146           TEST_VERIFY (memcmp (buf + 4, "\0\1\0\1\0\0\0\0", 8) == 0);
147           /* Question section.  */
148           static const char qname[] = "\3www\7example\3com";
149           size_t qname_length = sizeof (qname);
150           TEST_VERIFY (memcmp (buf + 12, qname, qname_length) == 0);
151           /* RDATA part of answer.  */
152           uint16_t type16 = type;
153           TEST_VERIFY (memcmp (buf + ret - 2, &type16, sizeof (type16)) == 0);
154         }
155     }
156 
157   TEST_VERIFY (func (-1, buf, sizeof (buf) == -1));
158   TEST_VERIFY (func (65536, buf, sizeof (buf) == -1));
159 }
160 
161 static int
do_test(void)162 do_test (void)
163 {
164   struct resolv_redirect_config config =
165     {
166       .response_callback = response,
167     };
168   struct resolv_test *obj = resolv_test_start (config);
169 
170   test_function ("res_query", &wrap_res_query);
171   test_function ("res_search", &wrap_res_search);
172   test_function ("res_querydomain", &wrap_res_querydomain);
173   test_function ("res_send", &wrap_res_send);
174 
175   test_function ("res_nquery", &wrap_res_nquery);
176   test_function ("res_nsearch", &wrap_res_nsearch);
177   test_function ("res_nquerydomain", &wrap_res_nquerydomain);
178   test_function ("res_nsend", &wrap_res_nsend);
179 
180   resolv_test_end (obj);
181   return 0;
182 }
183 
184 #define TIMEOUT 300
185 #include <support/test-driver.c>
186