1 /* $NetBSD: memory.c,v 1.1.1.2 2014/07/12 11:57:44 spz Exp $ */
2 /* memory.c
3
4 Memory-resident database... */
5
6 /*
7 * Copyright (c) 2004,2007,2009,2014 by Internet Systems Consortium, Inc. ("ISC")
8 * Copyright (c) 1995-2003 by Internet Software Consortium
9 *
10 * Permission to use, copy, modify, and distribute this software for any
11 * purpose with or without fee is hereby granted, provided that the above
12 * copyright notice and this permission notice appear in all copies.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
15 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
16 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
17 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
20 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 *
22 * Internet Systems Consortium, Inc.
23 * 950 Charter Street
24 * Redwood City, CA 94063
25 * <info@isc.org>
26 * https://www.isc.org/
27 *
28 */
29
30 #include <sys/cdefs.h>
31 __RCSID("$NetBSD: memory.c,v 1.1.1.2 2014/07/12 11:57:44 spz Exp $");
32
33 #include "dhcpd.h"
34
35 struct group *root_group;
36 group_hash_t *group_name_hash;
37 int (*group_write_hook) (struct group_object *);
38
delete_group(struct group_object * group,int writep)39 isc_result_t delete_group (struct group_object *group, int writep)
40 {
41 struct group_object *d;
42
43 /* The group should exist and be hashed - if not, it's invalid. */
44 if (group_name_hash) {
45 d = (struct group_object *)0;
46 group_hash_lookup (&d, group_name_hash, group -> name,
47 strlen (group -> name), MDL);
48 } else
49 return DHCP_R_INVALIDARG;
50 if (!d)
51 return DHCP_R_INVALIDARG;
52
53 /* Also not okay to delete a group that's not the one in
54 the hash table. */
55 if (d != group)
56 return DHCP_R_INVALIDARG;
57
58 /* If it's dynamic, and we're deleting it, we can just blow away the
59 hash table entry. */
60 if ((group -> flags & GROUP_OBJECT_DYNAMIC) &&
61 !(group -> flags & GROUP_OBJECT_STATIC)) {
62 group_hash_delete (group_name_hash,
63 group -> name, strlen (group -> name), MDL);
64 } else {
65 group -> flags |= GROUP_OBJECT_DELETED;
66 if (group -> group)
67 group_dereference (&group -> group, MDL);
68 }
69
70 /* Store the group declaration in the lease file. */
71 if (writep && group_write_hook) {
72 if (!(*group_write_hook) (group))
73 return ISC_R_IOERROR;
74 }
75 return ISC_R_SUCCESS;
76 }
77
supersede_group(struct group_object * group,int writep)78 isc_result_t supersede_group (struct group_object *group, int writep)
79 {
80 struct group_object *t;
81
82 /* Register the group in the group name hash table,
83 so we can look it up later. */
84 if (group_name_hash) {
85 t = (struct group_object *)0;
86 group_hash_lookup (&t, group_name_hash,
87 group -> name,
88 strlen (group -> name), MDL);
89 if (t && t != group) {
90 /* If this isn't a dynamic entry, then we need to flag
91 the replacement as not dynamic either - otherwise,
92 if the dynamic entry is deleted later, the static
93 entry will come back next time the server is stopped
94 and restarted. */
95 if (!(t -> flags & GROUP_OBJECT_DYNAMIC))
96 group -> flags |= GROUP_OBJECT_STATIC;
97
98 /* Delete the old object if it hasn't already been
99 deleted. If it has already been deleted, get rid of
100 the hash table entry. This is a legitimate
101 situation - a deleted static object needs to be kept
102 around so we remember it's deleted. */
103 if (!(t -> flags & GROUP_OBJECT_DELETED))
104 delete_group (t, 0);
105 else {
106 group_hash_delete (group_name_hash,
107 group -> name,
108 strlen (group -> name),
109 MDL);
110 group_object_dereference (&t, MDL);
111 }
112 }
113 } else {
114 group_new_hash(&group_name_hash, GROUP_HASH_SIZE, MDL);
115 t = (struct group_object *)0;
116 }
117
118 /* Add the group to the group name hash if it's not
119 already there, and also thread it into the list of
120 dynamic groups if appropriate. */
121 if (!t) {
122 group_hash_add (group_name_hash, group -> name,
123 strlen (group -> name), group, MDL);
124 }
125
126 /* Store the group declaration in the lease file. */
127 if (writep && group_write_hook) {
128 if (!(*group_write_hook) (group))
129 return ISC_R_IOERROR;
130 }
131 return ISC_R_SUCCESS;
132 }
133
clone_group(struct group ** gp,struct group * group,const char * file,int line)134 int clone_group (struct group **gp, struct group *group,
135 const char *file, int line)
136 {
137 struct group *g = (struct group *)0;
138
139 /* Normally gp should contain the null pointer, but for convenience
140 it's permissible to clone a group into itself. */
141 if (*gp && *gp != group)
142 return 0;
143 if (!group_allocate (&g, file, line))
144 return 0;
145 if (group == *gp)
146 *gp = (struct group *)0;
147 group_reference (gp, g, file, line);
148 g -> authoritative = group -> authoritative;
149 group_reference (&g -> next, group, file, line);
150 group_dereference (&g, file, line);
151 return 1;
152 }
153