info_hesiod.c revision 51292
1/*
2 * Copyright (c) 1997-1999 Erez Zadok
3 * Copyright (c) 1989 Jan-Simon Pendry
4 * Copyright (c) 1989 Imperial College of Science, Technology & Medicine
5 * Copyright (c) 1989 The Regents of the University of California.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry at Imperial College, London.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgment:
21 *      This product includes software developed by the University of
22 *      California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 *    may be used to endorse or promote products derived from this software
25 *    without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 *      %W% (Berkeley) %G%
40 *
41 * $Id: info_hesiod.c,v 1.5 1999/02/04 07:24:15 ezk Exp $
42 *
43 */
44
45/*
46 * Get info from Hesiod
47 */
48
49#ifdef HAVE_CONFIG_H
50# include <config.h>
51#endif /* HAVE_CONFIG_H */
52#include <am_defs.h>
53#include <amd.h>
54
55#define	HES_PREFIX	"hesiod."
56#define	HES_PREFLEN	7
57
58#ifdef HAVE_HESIOD_INIT
59/* bsdi3 does not define this extern in any header file */
60extern char **hesiod_resolve(void *context, const char *name, const char *type);
61extern int hesiod_init(void **context);
62static voidp hesiod_context;
63#endif /* HAVE_HESIOD_INIT */
64
65/* forward declarations */
66int amu_hesiod_init(mnt_map *m, char *map, time_t *tp);
67int hesiod_search(mnt_map *m, char *map, char *key, char **pval, time_t *tp);
68int hesiod_isup(mnt_map *m, char *map);
69
70/*
71 * No easy way to probe the server - check the map name begins with "hesiod."
72 * Note: this name includes 'amu_' so as to not conflict with libhesiod's
73 * hesiod_init() function.
74 */
75int
76amu_hesiod_init(mnt_map *m, char *map, time_t *tp)
77{
78#ifdef DEBUG
79  dlog("amu_hesiod_init(%s)", map);
80#endif /* DEBUG */
81  *tp = 0;
82
83#ifdef HAVE_HESIOD_INIT
84  if(!hesiod_context && hesiod_init(&hesiod_context) != 0)
85    return ENOENT;
86#endif /* HAVE_HESIOD_INIT */
87
88  return NSTREQ(map, HES_PREFIX, HES_PREFLEN) ? 0 : ENOENT;
89}
90
91
92/*
93 * Do a Hesiod nameserver call.
94 * Modify time is ignored by Hesiod - XXX
95 */
96int
97hesiod_search(mnt_map *m, char *map, char *key, char **pval, time_t *tp)
98{
99  char hes_key[MAXPATHLEN];
100  char **rvec;
101#ifndef HAVE_HESIOD_INIT
102  int error;
103#endif /* not HAVE_HESIOD_INIT */
104
105#ifdef DEBUG
106  dlog("hesiod_search(m=%lx, map=%s, key=%s, pval=%lx tp=%lx)",
107       (unsigned long) m, map, key, (unsigned long) pval, (unsigned long) tp);
108#endif /* DEBUG */
109
110  sprintf(hes_key, "%s.%s", key, map + HES_PREFLEN);
111
112  /*
113   * Call the resolver
114   */
115#ifdef DEBUG
116  dlog("Hesiod base is: %s\n", gopt.hesiod_base);
117  dlog("hesiod_search: hes_resolve(%s, %s)", hes_key, gopt.hesiod_base);
118  if (debug_flags & D_INFO)
119    _res.options |= RES_DEBUG;
120#endif /* DEBUG */
121
122#ifdef HAVE_HESIOD_INIT
123  /* new style hesiod */
124  rvec = hesiod_resolve(hesiod_context, hes_key, gopt.hesiod_base);
125#else /* not HAVE_HESIOD_INIT */
126  rvec = hes_resolve(hes_key, gopt.hesiod_base);
127#endif /* not HAVE_HESIOD_INIT */
128
129  /*
130   * If a reply was forthcoming then return
131   * it (and free subsequent replies)
132   */
133  if (rvec && *rvec) {
134    *pval = *rvec;
135    while (*++rvec)
136      XFREE(*rvec);
137    return 0;
138  }
139
140#ifdef HAVE_HESIOD_INIT
141  /* new style hesiod */
142  return errno;
143#else /* not HAVE_HESIOD_INIT */
144  /*
145   * Otherwise reflect the hesiod error into a Un*x error
146   */
147# ifdef DEBUG
148  dlog("hesiod_search: Error: %d", hes_error());
149# endif /* DEBUG */
150  switch (hes_error()) {
151  case HES_ER_NOTFOUND:
152    error = ENOENT;
153    break;
154  case HES_ER_CONFIG:
155    error = EIO;
156    break;
157  case HES_ER_NET:
158    error = ETIMEDOUT;
159    break;
160  default:
161    error = EINVAL;
162    break;
163  }
164# ifdef DEBUG
165  dlog("hesiod_search: Returning: %d", error);
166# endif /* DEBUG */
167  return error;
168#endif /* not HAVE_HESIOD_INIT */
169}
170
171
172/*
173 * Check if Hesiod is up, so we can determine if to clear the map or not.
174 * Test it by querying for /defaults.
175 * Returns: 0 if Hesiod is down, 1 if it is up.
176 */
177int
178hesiod_isup(mnt_map *m, char *map)
179{
180  int error;
181  char *val;
182  time_t mtime;
183  static int last_status = 1;	/* assume up by default */
184
185  error = hesiod_search(m, map, "/defaults", &val, &mtime);
186#ifdef DEBUG
187  dlog("hesiod_isup(%s): %s", map, strerror(error));
188#endif /* DEBUG */
189  if (error != 0 && error != ENOENT) {
190    plog(XLOG_ERROR,
191	 "hesiod_isup: error getting `/defaults' entry in map %s: %m", map);
192    last_status = 0;
193    return 0;			/* Hesiod is down */
194  }
195  if (last_status == 0) {	/* if was down before */
196    plog(XLOG_INFO, "hesiod_isup: Hesiod came back up for map %s", map);
197    last_status = 1;
198  }
199  return 1;			/* Hesiod is up */
200}
201