resolv/tst-bug18665.c

   1 /* Test for __libc_res_nsend buffer mismanagent (bug 18665), UDP case.
   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 <errno.h>
  20 #include <netdb.h>
  21 #include <resolv.h>
  22 #include <stdio.h>
  23 #include <string.h>
  24 #include <support/check.h>
  25 #include <support/resolv_test.h>
  26 #include <support/xthread.h>
  27
  28 static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
  29
  30 static int initial_address_count;
  31 static int response_count;
  32
  33 static void
  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   TEST_VERIFY_EXIT (qname != NULL);
  39   struct resolv_response_flags flags = {};
  40   resolv_response_init (b, flags);
  41   resolv_response_add_question (b, qname, qclass, qtype);
  42
  43   resolv_response_section (b, ns_s_an);
  44
  45   /* Add many A/AAAA records to the second response.  */
  46   int address_count;
  47   xpthread_mutex_lock (&lock);
  48   if (response_count == 0)
  49     address_count = initial_address_count;
  50   else
  51     address_count = 2000;
  52   ++response_count;
  53   xpthread_mutex_unlock (&lock);
  54
  55   for (int i = 0; i < address_count; ++i)
  56     {
  57       resolv_response_open_record (b, qname, qclass, qtype, 0);
  58       switch (qtype)
  59         {
  60         case T_A:
  61           {
  62             char ipv4[4] = {10, i >> 8, i, 0};
  63             ipv4[3] = 2 * ctx->tcp + 4 * ctx->server_index;
  64             resolv_response_add_data (b, &ipv4, sizeof (ipv4));
  65           }
  66           break;
  67         case T_AAAA:
  68           {
  69             char ipv6[16]
  70               = {0x20, 0x01, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  71                  i >> 8, i, 0};
  72             ipv6[15] = 2 * ctx->tcp + 4 * ctx->server_index;
  73             resolv_response_add_data (b, &ipv6, sizeof (ipv6));
  74           }
  75           break;
  76         default:
  77           support_record_failure ();
  78           printf ("error: unexpected QTYPE: %s/%u/%u\n",
  79                   qname, qclass, qtype);
  80         }
  81       resolv_response_close_record (b);
  82     }
  83 }
  84
  85 static void
  86 test_different_sizes (void)
  87 {
  88   struct addrinfo hints = { .ai_family = AF_UNSPEC, };
  89   struct addrinfo *ai;
  90   int ret;
  91
  92   /* This magic number produces a response size close to 2048
  93      bytes.  */
  94   initial_address_count = 126;
  95   response_count = 0;
  96
  97   ret = getaddrinfo ("www.example", "80", &hints, &ai);
  98   if (ret == 0)
  99     freeaddrinfo (ai);
 100
 101   response_count = 0;
 102   ret = getaddrinfo ("www123.example", "80", &hints, &ai);
 103   if (ret == 0)
 104     freeaddrinfo (ai);
 105
 106   response_count = 0;
 107   ret = getaddrinfo ("www1234.example", "80", &hints, &ai);
 108   if (ret == 0)
 109     freeaddrinfo (ai);
 110
 111   response_count = 0;
 112   ret = getaddrinfo ("www12345.example", "80", &hints, &ai);
 113   if (ret == 0)
 114     freeaddrinfo (ai);
 115 }
 116
 117 static int
 118 do_test (void)
 119 {
 120   struct resolv_test *obj = resolv_test_start
 121     ((struct resolv_redirect_config)
 122      {
 123        .response_callback = response
 124      });
 125
 126   test_different_sizes ();
 127
 128   _res.options |= RES_SNGLKUP;
 129   test_different_sizes ();
 130
 131   _res.options |= RES_SNGLKUPREOP;
 132   test_different_sizes ();
 133
 134   resolv_test_end (obj);
 135   return 0;
 136 }
 137
 138 #include <support/test-driver.c>