summaryrefslogtreecommitdiffstats
path: root/lib/dns/portlist.c
blob: 5bc89f4829840a3b867e1833ab417eebde51defc (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
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
/*
 * Copyright (C) 2004-2007  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2003  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/* $Id: portlist.c,v 1.13 2007/06/19 23:47:16 tbox Exp $ */

/*! \file */

#include <config.h>

#include <stdlib.h>

#include <isc/magic.h>
#include <isc/mem.h>
#include <isc/mutex.h>
#include <isc/net.h>
#include <isc/refcount.h>
#include <isc/result.h>
#include <isc/string.h>
#include <isc/types.h>
#include <isc/util.h>

#include <dns/types.h>
#include <dns/portlist.h>

#define DNS_PORTLIST_MAGIC	ISC_MAGIC('P','L','S','T')
#define DNS_VALID_PORTLIST(p)	ISC_MAGIC_VALID(p, DNS_PORTLIST_MAGIC)

typedef struct dns_element {
	in_port_t	port;
	isc_uint16_t	flags;
} dns_element_t;

struct dns_portlist {
	unsigned int	magic;
	isc_mem_t	*mctx;
	isc_refcount_t	refcount;
	isc_mutex_t	lock;
	dns_element_t 	*list;
	unsigned int	allocated;
	unsigned int	active;
};

#define DNS_PL_INET	0x0001
#define DNS_PL_INET6	0x0002
#define DNS_PL_ALLOCATE	16

static int
compare(const void *arg1, const void *arg2) {
	const dns_element_t *e1 = (const dns_element_t *)arg1;
	const dns_element_t *e2 = (const dns_element_t *)arg2;

	if (e1->port < e2->port)
		return (-1);
	if (e1->port > e2->port)
		return (1);
	return (0);
}

isc_result_t
dns_portlist_create(isc_mem_t *mctx, dns_portlist_t **portlistp) {
	dns_portlist_t *portlist;
	isc_result_t result;

	REQUIRE(portlistp != NULL && *portlistp == NULL);

	portlist = isc_mem_get(mctx, sizeof(*portlist));
	if (portlist == NULL)
		return (ISC_R_NOMEMORY);
        result = isc_mutex_init(&portlist->lock);
	if (result != ISC_R_SUCCESS) {
		isc_mem_put(mctx, portlist, sizeof(*portlist));
		return (result);
	}
	result = isc_refcount_init(&portlist->refcount, 1);
	if (result != ISC_R_SUCCESS) {
		DESTROYLOCK(&portlist->lock);
		isc_mem_put(mctx, portlist, sizeof(*portlist));
		return (result);
	}
	portlist->list = NULL;
	portlist->allocated = 0;
	portlist->active = 0;
	portlist->mctx = NULL;
	isc_mem_attach(mctx, &portlist->mctx);
	portlist->magic = DNS_PORTLIST_MAGIC;
	*portlistp = portlist;
	return (ISC_R_SUCCESS);
}

static dns_element_t *
find_port(dns_element_t *list, unsigned int len, in_port_t port) {
	unsigned int xtry = len / 2;
	unsigned int min = 0;
	unsigned int max = len - 1;
	unsigned int last = len;

	for (;;) {
		if (list[xtry].port == port)
			return (&list[xtry]);
	        if (port > list[xtry].port) {
			if (xtry == max)
				break;
			min = xtry;
			xtry = xtry + (max - xtry + 1) / 2;
			INSIST(xtry <= max);
			if (xtry == last)
				break;
			last = min;
		} else {
			if (xtry == min)
				break;
			max = xtry;
			xtry = xtry - (xtry - min + 1) / 2;
			INSIST(xtry >= min);
			if (xtry == last)
				break;
			last = max;
		}
	}
	return (NULL);
}

isc_result_t
dns_portlist_add(dns_portlist_t *portlist, int af, in_port_t port) {
	dns_element_t *el;
	isc_result_t result;

	REQUIRE(DNS_VALID_PORTLIST(portlist));
	REQUIRE(af == AF_INET || af == AF_INET6);

	LOCK(&portlist->lock);
	if (portlist->active != 0) {
		el = find_port(portlist->list, portlist->active, port);
		if (el != NULL) {
			if (af == AF_INET)
				el->flags |= DNS_PL_INET;
			else
				el->flags |= DNS_PL_INET6;
			result = ISC_R_SUCCESS;
			goto unlock;
		}
	}

	if (portlist->allocated <= portlist->active) {
		unsigned int allocated;
		allocated = portlist->allocated + DNS_PL_ALLOCATE;
		el = isc_mem_get(portlist->mctx, sizeof(*el) * allocated);
		if (el == NULL) {
			result = ISC_R_NOMEMORY;
			goto unlock;
		}
		if (portlist->list != NULL) {
			memcpy(el, portlist->list,
			       portlist->allocated * sizeof(*el)); 
			isc_mem_put(portlist->mctx, portlist->list,
				    portlist->allocated * sizeof(*el));
		}
		portlist->list = el;
		portlist->allocated = allocated;
	}
	portlist->list[portlist->active].port = port;
	if (af == AF_INET)
		portlist->list[portlist->active].flags = DNS_PL_INET;
	else
		portlist->list[portlist->active].flags = DNS_PL_INET6;
	portlist->active++;
	qsort(portlist->list, portlist->active, sizeof(*el), compare);
	result = ISC_R_SUCCESS;
 unlock:
	UNLOCK(&portlist->lock);
	return (result);
}

void
dns_portlist_remove(dns_portlist_t *portlist, int af, in_port_t port) {
	dns_element_t *el;

	REQUIRE(DNS_VALID_PORTLIST(portlist));
	REQUIRE(af == AF_INET || af == AF_INET6);

	LOCK(&portlist->lock);
	if (portlist->active != 0) {
		el = find_port(portlist->list, portlist->active, port);
		if (el != NULL) {
			if (af == AF_INET)
				el->flags &= ~DNS_PL_INET;
			else
				el->flags &= ~DNS_PL_INET6;
			if (el->flags == 0) {
				*el = portlist->list[portlist->active];
				portlist->active--;
				qsort(portlist->list, portlist->active,
				      sizeof(*el), compare);
			}
		}
	}
	UNLOCK(&portlist->lock);
}

isc_boolean_t
dns_portlist_match(dns_portlist_t *portlist, int af, in_port_t port) {
	dns_element_t *el;
	isc_boolean_t result = ISC_FALSE;
	
	REQUIRE(DNS_VALID_PORTLIST(portlist));
	REQUIRE(af == AF_INET || af == AF_INET6);
	LOCK(&portlist->lock);
	if (portlist->active != 0) {
		el = find_port(portlist->list, portlist->active, port);
		if (el != NULL) {
			if (af == AF_INET && (el->flags & DNS_PL_INET) != 0)
				result = ISC_TRUE;
			if (af == AF_INET6 && (el->flags & DNS_PL_INET6) != 0)
				result = ISC_TRUE;
		}
	}	
	UNLOCK(&portlist->lock);
	return (result);
}

void
dns_portlist_attach(dns_portlist_t *portlist, dns_portlist_t **portlistp) {

	REQUIRE(DNS_VALID_PORTLIST(portlist));
	REQUIRE(portlistp != NULL && *portlistp == NULL);

	isc_refcount_increment(&portlist->refcount, NULL);
	*portlistp = portlist;
}

void
dns_portlist_detach(dns_portlist_t **portlistp) {
	dns_portlist_t *portlist;
	unsigned int count;

	REQUIRE(portlistp != NULL);
	portlist = *portlistp;
	REQUIRE(DNS_VALID_PORTLIST(portlist));
	*portlistp = NULL;
	isc_refcount_decrement(&portlist->refcount, &count);
	if (count == 0) {
		portlist->magic = 0;
		isc_refcount_destroy(&portlist->refcount);
		if (portlist->list != NULL)
			isc_mem_put(portlist->mctx, portlist->list,
				    portlist->allocated *
				    sizeof(*portlist->list));
		DESTROYLOCK(&portlist->lock);
		isc_mem_putanddetach(&portlist->mctx, portlist,
				     sizeof(*portlist));
	}
}