aboutsummaryrefslogtreecommitdiff
path: root/nis/nis_findserv.c
blob: a04abd80564645f21860079632081c969c8fd40e (plain)
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
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
/* Copyright (C) 1997 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <rpc/pmap_prot.h>
#include <rpc/pmap_clnt.h>
#include <rpcsvc/nis.h>

#include "nis_intern.h"

/* Private data kept per client handle, from sunrpc/clnt_udp.c */
struct cu_data
  {
    int cu_sock;
    bool_t cu_closeit;
    struct sockaddr_in cu_raddr;
    int cu_rlen;
    struct timeval cu_wait;
    struct timeval cu_total;
    struct rpc_err cu_error;
    XDR cu_outxdrs;
    u_int cu_xdrpos;
    u_int cu_sendsz;
    char *cu_outbuf;
    u_int cu_recvsz;
    char cu_inbuf[1];
  };


/* The following is the original routine from sunrpc/pm_getport.c.
   The only change is the much shorter timeout. */
/*
 * pmap_getport.c
 * Client interface to pmap rpc service.
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 */

/*
 * Find the mapped port for program,version.
 * Calls the pmap service remotely to do the lookup.
 * Returns 0 if no map exists.
 */
static u_short
__pmap_getport (struct sockaddr_in *address, u_long program,
		u_long version, u_int protocol)
{
  const struct timeval timeout = {1, 0};
  const struct timeval tottimeout = {1, 0};
  u_short port = 0;
  int socket = -1;
  CLIENT *client;
  struct pmap parms;

  address->sin_port = htons (PMAPPORT);
  client = clntudp_bufcreate (address, PMAPPROG, PMAPVERS, timeout, &socket,
			      RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
  if (client != (CLIENT *) NULL)
    {
      parms.pm_prog = program;
      parms.pm_vers = version;
      parms.pm_prot = protocol;
      parms.pm_port = 0;	/* not needed or used */
      if (CLNT_CALL (client, PMAPPROC_GETPORT, (xdrproc_t) xdr_pmap,
		     (caddr_t) & parms, (xdrproc_t) xdr_u_short,
		     (caddr_t) & port, tottimeout) != RPC_SUCCESS)
	{
	  rpc_createerr.cf_stat = RPC_PMAPFAILURE;
	  clnt_geterr (client, &rpc_createerr.cf_error);
	}
      else if (port == 0)
	{
	  rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
	}
      CLNT_DESTROY (client);
    }
  /* (void)close(socket); CLNT_DESTROY already closed it */
  address->sin_port = 0;
  return port;
}

/* Transmit to NULLPROC, return immediately. */
static void *
nis_null_3_send (void *argp, CLIENT * clnt)
{
  static char clnt_res;
  struct timeval TIMEOUT = {0, 0};

  memset ((char *) &clnt_res, 0, sizeof (clnt_res));
  if (clnt_call (clnt, NULLPROC,
		 (xdrproc_t) xdr_void, (caddr_t) argp,
		 (xdrproc_t) xdr_void, (caddr_t) & clnt_res,
		 TIMEOUT) != RPC_SUCCESS)
    return NULL;
  return (void *) &clnt_res;
}

/* Receive request from NULLPROC asynchronously. */
static void *
nis_null_3_recv (void *argp, CLIENT * clnt)
{
  static char clnt_res;
  struct timeval TIMEOUT = {0, 0};

  memset ((char *) &clnt_res, 0, sizeof (clnt_res));
  if (clnt_call (clnt, NULLPROC,
		 (xdrproc_t) NULL, (caddr_t) argp,
		 (xdrproc_t) xdr_void, (caddr_t) & clnt_res,
		 TIMEOUT) != RPC_SUCCESS)
    return NULL;
  return (void *) &clnt_res;
}

/* This is now the public functions, which should find the fastest server */

struct findserv_req
{
  struct sockaddr_in sin;
  u_long xid;
  u_int server_nr;
  u_int server_ep;
};

long
__nis_findfastest (dir_binding * bind)
{
  struct timeval TIMEOUT = {5, 0};
  struct findserv_req **pings;
  struct sockaddr_in sin;
  int found = -1;
  time_t xid_seed, xid_lookup;
  int sock, dontblock = 1;
  CLIENT *clnt;
  void *foo = NULL;
  u_long i, j, pings_count, pings_max;
  struct cu_data *cu;

  pings_max = bind->server_len * 2;	/* Reserve a little bit more memory
					   for multihomed hosts */
  pings_count = 0;
  pings = malloc (sizeof (struct findserv_req *) * pings_max);
  xid_seed = time (NULL) ^ getpid ();

  memset (&sin, '\0', sizeof (sin));
  sin.sin_family = AF_INET;
  for (i = 0; i < bind->server_len; i++)
    for (j = 0; j < bind->server_val[i].ep.ep_len; ++j)
      if (strcmp (bind->server_val[i].ep.ep_val[j].family, "inet") == 0)
	if (strcmp (bind->server_val[i].ep.ep_val[j].proto, "-") == 0)
	  {
	    sin.sin_addr.s_addr =
	      inetstr2int (bind->server_val[i].ep.ep_val[j].uaddr);
	    if (sin.sin_addr.s_addr == 0)
	      continue;
	    sin.sin_port = htons (__pmap_getport (&sin, NIS_PROG,
						  NIS_VERSION, IPPROTO_UDP));
	    if (sin.sin_port == 0)
	      continue;

	    if (pings_count >= pings_max)
	      {
		pings_max += 10;
		pings = realloc (pings, sizeof (struct findserv_req) *
				 pings_max);
	      }
	    pings[pings_count] = calloc (1, sizeof (struct findserv_req));
	    memcpy ((char *) &pings[pings_count]->sin, (char *) &sin,
		    sizeof (sin));
	    pings[pings_count]->xid = xid_seed;
	    pings[pings_count]->server_nr = i;
	    pings[pings_count]->server_ep = j;
	    ++xid_seed;
	    ++pings_count;
	  }

  /* Make sure at least one server was assigned */
  if (pings_count == 0)
    {
      free (pings);
      return -1;
    }

  /* Create RPC handle */
  sock = socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP);
  clnt = clntudp_create (&sin, NIS_PROG, NIS_VERSION, TIMEOUT, &sock);
  if (clnt == NULL)
    {
      close (sock);
      for (i = 0; i < pings_count; ++i)
	free (pings[i]);
      free (pings);
      return -1;
    }
  clnt->cl_auth = authunix_create_default ();
  cu = (struct cu_data *) clnt->cl_private;
  TIMEOUT.tv_sec = 0;
  clnt_control (clnt, CLSET_TIMEOUT, (char *) &TIMEOUT);
  ioctl (sock, FIONBIO, &dontblock);

  /* Send to all servers the NULLPROC */
  for (i = 0; i < pings_count; ++i)
    {
      /* clntudp_call() will increment, subtract one */
      *((u_int32_t *) (cu->cu_outbuf)) = pings[i]->xid - 1;
      bcopy ((char *) &pings[i]->sin, (char *) &cu->cu_raddr,
	     sizeof (struct sockaddr_in));
      nis_null_3_send (foo, clnt);
    }

  /* Receive reply */
  nis_null_3_recv (foo, clnt);

  xid_lookup = *((u_int32_t *) (cu->cu_inbuf));
  for (i = 0; i < pings_count; i++)
    {
      if (pings[i]->xid == xid_lookup)
	{
	  bind->server_used = pings[i]->server_nr;
	  bind->current_ep = pings[i]->server_ep;
	  found = 1;
	}
    }

  auth_destroy (clnt->cl_auth);
  clnt_destroy (clnt);
  close (sock);

  for (i = 0; i < pings_count; ++i)
    free (pings[i]);
  free (pings);

  return found;
}