sunrpc/tst-svc_register.c

   1 /* Test svc_register/svc_unregister rpcbind interaction (bug 5010).
   2    Copyright (C) 2017-2022 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 /* This test uses a stub rpcbind server (implemented in a child
  20    process using rpcbind_dispatch/run_rpcbind) to check how RPC
  21    services are registered and unregistered using the rpcbind
  22    protocol.  For each subtest, a separate rpcbind test server is
  23    spawned and terminated.  */
  24
  25 #include <errno.h>
  26 #include <netinet/in.h>
  27 #include <rpc/clnt.h>
  28 #include <rpc/pmap_prot.h>
  29 #include <rpc/svc.h>
  30 #include <signal.h>
  31 #include <support/check.h>
  32 #include <support/namespace.h>
  33 #include <support/test-driver.h>
  34 #include <support/xsocket.h>
  35 #include <support/xthread.h>
  36 #include <support/xunistd.h>
  37 #include <sys/socket.h>
  38 #include <sys/wait.h>
  39 #include <unistd.h>
  40
  41 #include <libc-symbols.h>
  42 #include <shlib-compat.h>
  43
  44 /* These functions are only available as compat symbols.  */
  45 compat_symbol_reference (libc, xdr_pmap, xdr_pmap, GLIBC_2_0);
  46 compat_symbol_reference (libc, svc_unregister, svc_unregister, GLIBC_2_0);
  47
  48 /* Server callback for the unused RPC service which is registered and
  49    unregistered.  */
  50 static void
  51 server_dispatch (struct svc_req *request, SVCXPRT *transport)
  52 {
  53   FAIL_EXIT1 ("server_dispatch called");
  54 }
  55
  56 /* The port on which rpcbind listens for incoming requests.  */
  57 static inline struct sockaddr_in
  58 rpcbind_address (void)
  59 {
  60   return (struct sockaddr_in)
  61     {
  62       .sin_family = AF_INET,
  63       .sin_addr.s_addr = htonl (INADDR_LOOPBACK),
  64       .sin_port = htons (PMAPPORT)
  65     };
  66 }
  67
  68 /* Data provided by the test server after running the test, to see
  69    that the expected calls (and only those) happened.  */
  70 struct test_state
  71 {
  72   bool_t set_called;
  73   bool_t unset_called;
  74 };
  75
  76 static bool_t
  77 xdr_test_state (XDR *xdrs, void *data, ...)
  78 {
  79   struct test_state *p = data;
  80   return xdr_bool (xdrs, &p->set_called)
  81     && xdr_bool (xdrs, &p->unset_called);
  82 }
  83
  84 enum
  85 {
  86   /* Coordinates of our test service.  These numbers are
  87      arbitrary.  */
  88   PROGNUM = 123,
  89   VERSNUM = 456,
  90
  91   /* Extension for this test.  */
  92   PROC_GET_STATE_AND_EXIT = 10760
  93 };
  94
  95 /* Dummy implementation of the rpcbind service, with the
  96    PROC_GET_STATE_AND_EXIT extension.  */
  97 static void
  98 rpcbind_dispatch (struct svc_req *request, SVCXPRT *transport)
  99 {
 100   static struct test_state state = { 0, };
 101
 102   if (test_verbose)
 103     printf ("info: rpcbind request %lu\n", request->rq_proc);
 104
 105   switch (request->rq_proc)
 106     {
 107     case PMAPPROC_SET:
 108     case PMAPPROC_UNSET:
 109       TEST_VERIFY (state.set_called == (request->rq_proc == PMAPPROC_UNSET));
 110       TEST_VERIFY (!state.unset_called);
 111
 112       struct pmap query = { 0, };
 113       TEST_VERIFY
 114         (svc_getargs (transport, (xdrproc_t) xdr_pmap, (void *) &query));
 115       if (test_verbose)
 116         printf ("  pm_prog=%lu pm_vers=%lu pm_prot=%lu pm_port=%lu\n",
 117                 query.pm_prog, query.pm_vers, query.pm_prot, query.pm_port);
 118       TEST_VERIFY (query.pm_prog == PROGNUM);
 119       TEST_VERIFY (query.pm_vers == VERSNUM);
 120
 121       if (request->rq_proc == PMAPPROC_SET)
 122         state.set_called = TRUE;
 123       else
 124         state.unset_called = TRUE;
 125
 126       bool_t result = TRUE;
 127       TEST_VERIFY (svc_sendreply (transport,
 128                                   (xdrproc_t) xdr_bool, (void *) &result));
 129       break;
 130
 131     case PROC_GET_STATE_AND_EXIT:
 132       TEST_VERIFY (svc_sendreply (transport,
 133                                   xdr_test_state, (void *) &state));
 134       _exit (0);
 135       break;
 136
 137     default:
 138       FAIL_EXIT1 ("invalid rq_proc value: %lu", request->rq_proc);
 139     }
 140 }
 141
 142 /* Run the rpcbind test server.  */
 143 static void
 144 run_rpcbind (int rpcbind_sock)
 145 {
 146   SVCXPRT *rpcbind_transport = svcudp_create (rpcbind_sock);
 147   TEST_VERIFY (svc_register (rpcbind_transport, PMAPPROG, PMAPVERS,
 148                              rpcbind_dispatch,
 149                              /* Do not register with rpcbind.  */
 150                              0));
 151   svc_run ();
 152 }
 153
 154 /* Call out to the rpcbind test server to retrieve the test status
 155    information.  */
 156 static struct test_state
 157 get_test_state (void)
 158 {
 159   int socket = RPC_ANYSOCK;
 160   struct sockaddr_in address = rpcbind_address ();
 161   CLIENT *client = clntudp_create
 162     (&address, PMAPPROG, PMAPVERS, (struct timeval) { 1, 0}, &socket);
 163   struct test_state result = { 0 };
 164   TEST_VERIFY (clnt_call (client, PROC_GET_STATE_AND_EXIT,
 165                           (xdrproc_t) xdr_void, NULL,
 166                           xdr_test_state, (void *) &result,
 167                           ((struct timeval) { 3, 0}))
 168                == RPC_SUCCESS);
 169   clnt_destroy (client);
 170   return result;
 171 }
 172
 173 /* Used by test_server_thread to receive test parameters.  */
 174 struct test_server_args
 175 {
 176   bool use_rpcbind;
 177   bool use_unregister;
 178 };
 179
 180 /* RPC test server.  Used to verify the svc_unregister behavior during
 181    thread cleanup.  */
 182 static void *
 183 test_server_thread (void *closure)
 184 {
 185   struct test_server_args *args = closure;
 186   SVCXPRT *transport = svcudp_create (RPC_ANYSOCK);
 187   int protocol;
 188   if (args->use_rpcbind)
 189     protocol = IPPROTO_UDP;
 190   else
 191     /* Do not register with rpcbind.  */
 192     protocol = 0;
 193   TEST_VERIFY (svc_register (transport, PROGNUM, VERSNUM,
 194                              server_dispatch, protocol));
 195   if (args->use_unregister)
 196     svc_unregister (PROGNUM, VERSNUM);
 197   SVC_DESTROY (transport);
 198   return NULL;
 199 }
 200
 201 static int
 202 do_test (void)
 203 {
 204   support_become_root ();
 205   support_enter_network_namespace ();
 206
 207   /* Try to bind to the rpcbind port.  */
 208   int rpcbind_sock = xsocket (AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
 209   {
 210     struct sockaddr_in sin = rpcbind_address ();
 211     if (bind (rpcbind_sock, (struct sockaddr *) &sin, sizeof (sin)) != 0)
 212       {
 213         /* If the port is not available, we cannot run this test.  */
 214         printf ("warning: could not bind to rpcbind port %d: %m\n",
 215                 (int) PMAPPORT);
 216         return EXIT_UNSUPPORTED;
 217       }
 218   }
 219
 220   for (int use_thread = 0; use_thread < 2; ++use_thread)
 221     for (int use_rpcbind = 0; use_rpcbind < 2; ++use_rpcbind)
 222       for (int use_unregister = 0; use_unregister < 2; ++use_unregister)
 223         {
 224           if (test_verbose)
 225             printf ("info: * use_thread=%d use_rpcbind=%d use_unregister=%d\n",
 226                     use_thread, use_rpcbind, use_unregister);
 227
 228           /* Create the subprocess which runs the actual test.  The
 229              kernel will queue the UDP packets to the rpcbind
 230              process.  */
 231           pid_t svc_pid = xfork ();
 232           if (svc_pid == 0)
 233             {
 234               struct test_server_args args =
 235                 {
 236                   .use_rpcbind = use_rpcbind,
 237                   .use_unregister = use_unregister,
 238                 };
 239               if (use_thread)
 240                 xpthread_join (xpthread_create
 241                                (NULL, test_server_thread, &args));
 242               else
 243                 test_server_thread (&args);
 244               /* We cannnot use _exit here because we want to test the
 245                  process cleanup.  */
 246               exit (0);
 247             }
 248
 249           /* Create the subprocess for the rpcbind test server.  */
 250           pid_t rpcbind_pid = xfork ();
 251           if (rpcbind_pid == 0)
 252             run_rpcbind (rpcbind_sock);
 253
 254           int status;
 255           xwaitpid (svc_pid, &status, 0);
 256           TEST_VERIFY (WIFEXITED (status) && WEXITSTATUS (status) == 0);
 257
 258           if (!use_rpcbind)
 259             /* Wait a bit, to see if the packet arrives on the rpcbind
 260                port.  The choice is of the timeout is arbitrary, but
 261                should be long enough even for slow/busy systems.  For
 262                the use_rpcbind case, waiting on svc_pid above makes
 263                sure that the test server has responded because
 264                svc_register/svc_unregister are supposed to wait for a
 265                reply.  */
 266             usleep (300 * 1000);
 267
 268           struct test_state state = get_test_state ();
 269           if (use_rpcbind)
 270             {
 271               TEST_VERIFY (state.set_called);
 272               if (use_thread || use_unregister)
 273                 /* Thread cleanup or explicit svc_unregister will
 274                    result in a rpcbind unset RPC call.  */
 275                 TEST_VERIFY (state.unset_called);
 276               else
 277                 /* This is arguably a bug: Regular process termination
 278                    does not unregister the service with rpcbind.  The
 279                    unset rpcbind call happens from a __libc_subfreeres
 280                    callback, and this only happens when running under
 281                    memory debuggers such as valgrind.  */
 282                 TEST_VERIFY (!state.unset_called);
 283             }
 284           else
 285             {
 286               /* If rpcbind registration is not requested, we do not
 287                  expect any rpcbind calls.  */
 288               TEST_VERIFY (!state.set_called);
 289               TEST_VERIFY (!state.unset_called);
 290             }
 291
 292           xwaitpid (rpcbind_pid, &status, 0);
 293           TEST_VERIFY (WIFEXITED (status) && WEXITSTATUS (status) == 0);
 294         }
 295
 296   return 0;
 297 }
 298
 299 #include <support/test-driver.c>