xref: /openbsd/usr.sbin/bgpd/pftable.c (revision 7b36286a)
1 /*	$OpenBSD: pftable.c,v 1.5 2005/07/01 09:19:24 claudio Exp $ */
2 
3 /*
4  * Copyright (c) 2004 Damien Miller <djm@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/ioctl.h>
21 #include <sys/socket.h>
22 
23 #include <net/if.h>
24 #include <net/pfvar.h>
25 
26 #include <stdlib.h>
27 #include <string.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 
31 /* Namespace collision: these are defined in both bgpd.h and pfvar.h */
32 #undef v4
33 #undef v6
34 #undef addr8
35 #undef addr16
36 #undef addr32
37 
38 #include "bgpd.h"
39 
40 static int devpf = -1;
41 
42 struct pf_table {
43 	LIST_ENTRY(pf_table)	entry;
44 	char			name[PFTABLE_LEN];
45 	unsigned long		what;
46 	struct pfr_addr		*worklist;
47 	int			naddrs;
48 	int			nalloc;
49 };
50 
51 /* List of tables under management */
52 LIST_HEAD(, pf_table) tables = LIST_HEAD_INITIALIZER(tables);
53 
54 static int
55 pftable_change(struct pf_table *pft)
56 {
57 	struct pfioc_table tio;
58 	int ret;
59 
60 	if (pft->naddrs == 0 || pft->what == 0)
61 		return (0);
62 
63 	if (devpf == -1 && ((devpf = open("/dev/pf", O_RDWR)) == -1))
64 		fatal("open(/dev/pf)");
65 
66 	bzero(&tio, sizeof(tio));
67 	strlcpy(tio.pfrio_table.pfrt_name, pft->name,
68 	    sizeof(tio.pfrio_table.pfrt_name));
69 	tio.pfrio_buffer = pft->worklist;
70 	tio.pfrio_esize = sizeof(*pft->worklist);
71 	tio.pfrio_size = pft->naddrs;
72 
73 	ret = ioctl(devpf, pft->what, &tio);
74 
75 	/* bad prefixes shouldn't cause us to die */
76 	if (ret == -1) {
77 		if (errno == EINVAL)
78 			return (0);
79 		log_warn("pftable_change ioctl");
80 	}
81 
82 	return (ret);
83 }
84 
85 static int
86 pftable_clear(const char *name)
87 {
88 	struct pfioc_table tio;
89 
90 	if (devpf == -1 && ((devpf = open("/dev/pf", O_RDWR)) == -1))
91 		fatal("open(/dev/pf)");
92 
93 	bzero(&tio, sizeof(tio));
94 	strlcpy(tio.pfrio_table.pfrt_name, name,
95 	    sizeof(tio.pfrio_table.pfrt_name));
96 
97 	if (ioctl(devpf, DIOCRCLRADDRS, &tio) != 0) {
98 		log_warn("pftable_clear ioctl");
99 		return (-1);
100 	}
101 
102 	return (0);
103 }
104 
105 int
106 pftable_exists(const char *name)
107 {
108 	struct pfioc_table tio;
109 	struct pfr_astats dummy;
110 
111 	if (devpf == -1 && ((devpf = open("/dev/pf", O_RDWR)) == -1))
112 		fatal("open(/dev/pf)");
113 
114 	bzero(&tio, sizeof(tio));
115 	strlcpy(tio.pfrio_table.pfrt_name, name,
116 	    sizeof(tio.pfrio_table.pfrt_name));
117 	tio.pfrio_buffer = &dummy;
118 	tio.pfrio_esize = sizeof(dummy);
119 	tio.pfrio_size = 1;
120 
121 	if (ioctl(devpf, DIOCRGETASTATS, &tio) != 0)
122 		return (-1);
123 
124 	return (0);
125 }
126 
127 int
128 pftable_add(const char *name)
129 {
130 	struct pf_table *pft;
131 
132 	/* Ignore duplicates */
133 	LIST_FOREACH(pft, &tables, entry)
134 		if (strcmp(pft->name, name) == 0)
135 			return (0);
136 
137 	if ((pft = malloc(sizeof(*pft))) == NULL) {
138 		log_warn("pftable malloc");
139 		return (-1);
140 	}
141 
142 	bzero(pft, sizeof(*pft));
143 	if (strlcpy(pft->name, name, sizeof(pft->name)) >= sizeof(pft->name)) {
144 		log_warn("pf_table name too long");
145 		free(pft);
146 		return (-1);
147 	}
148 
149 	LIST_INSERT_HEAD(&tables, pft, entry);
150 
151 	return (0);
152 }
153 
154 int
155 pftable_clear_all(void)
156 {
157 	struct pf_table *pft;
158 
159 	LIST_FOREACH(pft, &tables, entry) {
160 		if (pftable_clear(pft->name) != 0)
161 			return (-1);
162 		if (pft->worklist != NULL) {
163 			free(pft->worklist);
164 			pft->worklist = NULL;
165 		}
166 		pft->nalloc = pft->naddrs = 0;
167 		pft->what = 0;
168 	}
169 
170 	return (0);
171 }
172 
173 static int
174 pftable_add_work(const char *table, struct bgpd_addr *addr,
175     u_int8_t len, int del)
176 {
177 	struct pf_table *pft;
178 	struct pfr_addr *pfa, *tmp;
179 	unsigned long what;
180 
181 	if (*table == '\0' || len > 128)
182 		fatal("pftable_add_work: insane");
183 
184 	/* Find table */
185 	LIST_FOREACH(pft, &tables, entry)
186 		if (strcmp(pft->name, table) == 0)
187 			break;
188 
189 	if (pft == NULL) {
190 		log_warn("pf table %s not found", table);
191 		return (-1);
192 	}
193 
194 	/* Only one type of work on the list at a time */
195 	what = del ? DIOCRDELADDRS : DIOCRADDADDRS;
196 	if (pft->naddrs != 0 && pft->what != what)
197 		fatal("attempt to mix pf table additions/deletions");
198 
199 	if (pft->nalloc <= pft->naddrs)
200 		pft->nalloc = pft->nalloc == 0 ? 1 : pft->nalloc * 2;
201 	tmp = realloc(pft->worklist, sizeof(*tmp) * pft->nalloc);
202 	if (tmp == NULL) {
203 		if (pft->worklist != NULL) {
204 			log_warn("pftable_add_work: malloc");
205 			free(pft->worklist);
206 			pft->worklist = NULL;
207 		}
208 		pft->nalloc = pft->naddrs = 0;
209 		pft->what = 0;
210 		return (-1);
211 	}
212 	pft->worklist = tmp;
213 	pfa = &pft->worklist[pft->naddrs];
214 
215 	bzero(pfa, sizeof(*pfa));
216 	memcpy(&pfa->pfra_u, &addr->ba, (len + 7U) / 8);
217 	pfa->pfra_af = addr->af;
218 	pfa->pfra_net = len;
219 
220 	pft->naddrs++;
221 	pft->what = what;
222 
223 	/* Don't let the list grow too large */
224 	if (pft->naddrs >= 1024)
225 		pftable_commit();
226 
227 	return (0);
228 }
229 
230 /* imsg handlers */
231 int
232 pftable_addr_add(struct pftable_msg *m)
233 {
234 	return (pftable_add_work(m->pftable, &m->addr, m->len, 0));
235 }
236 
237 int
238 pftable_addr_remove(struct pftable_msg *m)
239 {
240 	return (pftable_add_work(m->pftable, &m->addr, m->len, 1));
241 }
242 
243 int
244 pftable_commit(void)
245 {
246 	struct pf_table *pft;
247 	int ret = 0;
248 
249 	LIST_FOREACH(pft, &tables, entry) {
250 		if (pft->what != 0 && pftable_change(pft) != 0)
251 			ret = -1;
252 		if (pft->worklist != NULL)
253 			free(pft->worklist);
254 		pft->worklist = NULL;
255 		pft->nalloc = pft->naddrs = 0;
256 		pft->what = 0;
257 	}
258 
259 	return (ret);
260 }
261 
262