xref: /freebsd/sbin/pfilctl/pfilctl.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019 Gleb Smirnoff <glebius@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/ioctl.h>
30 #include <net/if.h>
31 #include <net/pfil.h>
32 
33 #include <err.h>
34 #include <fcntl.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 
40 static int dev;
41 
42 static const char * const typenames[] = {
43 	[PFIL_TYPE_IP4] = "IPv4",
44 	[PFIL_TYPE_IP6] = "IPv6",
45 	[PFIL_TYPE_ETHERNET] = "Ethernet",
46 };
47 
48 static void listheads(int argc, char *argv[]);
49 static void listhooks(int argc, char *argv[]);
50 static void hook(int argc, char *argv[]);
51 static void help(void);
52 
53 static const struct cmd {
54 	const char	*cmd_name;
55 	void		(*cmd_func)(int argc, char *argv[]);
56 } cmds[] = {
57 	{ "heads",	listheads },
58 	{ "hooks",	listhooks },
59 	{ "link",	hook },
60 	{ "unlink",	hook },
61 	{ NULL,		NULL },
62 };
63 
64 int
65 main(int argc __unused, char *argv[] __unused)
66 {
67 	int cmd = -1;
68 
69 	if (--argc == 0)
70 		help();
71 	argv++;
72 
73 	for (int i = 0; cmds[i].cmd_name != NULL; i++)
74 		if (!strncmp(argv[0], cmds[i].cmd_name, strlen(argv[0]))) {
75 			if (cmd != -1)
76 				errx(1, "ambiguous command: %s", argv[0]);
77 			cmd = i;
78 		}
79 	if (cmd == -1)
80 		errx(1, "unknown command: %s", argv[0]);
81 
82 	dev = open("/dev/" PFILDEV, O_RDWR);
83 	if (dev == -1)
84 		err(1, "open(%s)", "/dev/" PFILDEV);
85 
86 	(*cmds[cmd].cmd_func)(argc, argv);
87 
88 	return (0);
89 }
90 
91 static void
92 help(void)
93 {
94 
95 	fprintf(stderr, "usage: %s (heads|hooks|link|unlink)\n", getprogname());
96 	exit(0);
97 }
98 
99 static void
100 listheads(int argc __unused, char *argv[] __unused)
101 {
102 	struct pfilioc_list plh;
103 	u_int nheads, nhooks, i;
104 	int j, h;
105 
106 	plh.pio_nheads = 0;
107 	plh.pio_nhooks = 0;
108 	if (ioctl(dev, PFILIOC_LISTHEADS, &plh) != 0)
109 		err(1, "ioctl(PFILIOC_LISTHEADS)");
110 
111 retry:
112 	plh.pio_heads = calloc(plh.pio_nheads, sizeof(struct pfilioc_head));
113 	if (plh.pio_heads == NULL)
114 		err(1, "malloc");
115 	plh.pio_hooks = calloc(plh.pio_nhooks, sizeof(struct pfilioc_hook));
116 	if (plh.pio_hooks == NULL)
117 		err(1, "malloc");
118 
119 	nheads = plh.pio_nheads;
120 	nhooks = plh.pio_nhooks;
121 
122 	if (ioctl(dev, PFILIOC_LISTHEADS, &plh) != 0)
123 		err(1, "ioctl(PFILIOC_LISTHEADS)");
124 
125 	if (plh.pio_nheads > nheads || plh.pio_nhooks > nhooks) {
126 		free(plh.pio_heads);
127 		free(plh.pio_hooks);
128 		goto retry;
129 	}
130 
131 #define	FMTHD	"%16s %8s\n"
132 #define	FMTHK	"%29s %16s:%s\n"
133 	printf("%16s %8s %3s %16s\n", "Intercept point", "Type", "Dir", "Hook");
134 	for (i = 0, h = 0; i < plh.pio_nheads; i++) {
135 		printf(FMTHD, plh.pio_heads[i].pio_name,
136 		    typenames[plh.pio_heads[i].pio_type]);
137 		for (j = 0; j < plh.pio_heads[i].pio_nhooksin; j++, h++)
138 			printf(FMTHK, "In", plh.pio_hooks[h].pio_module,
139 			    plh.pio_hooks[h].pio_ruleset);
140 		for (j = 0; j < plh.pio_heads[i].pio_nhooksout; j++, h++)
141 			printf(FMTHK, "Out", plh.pio_hooks[h].pio_module,
142 			    plh.pio_hooks[h].pio_ruleset);
143 	}
144 }
145 
146 static void
147 listhooks(int argc __unused, char *argv[] __unused)
148 {
149 	struct pfilioc_list plh;
150 	u_int nhooks, i;
151 
152 	plh.pio_nhooks = 0;
153 	if (ioctl(dev, PFILIOC_LISTHEADS, &plh) != 0)
154 		err(1, "ioctl(PFILIOC_LISTHEADS)");
155 retry:
156 	plh.pio_hooks = calloc(plh.pio_nhooks, sizeof(struct pfilioc_hook));
157 	if (plh.pio_hooks == NULL)
158 		err(1, "malloc");
159 
160 	nhooks = plh.pio_nhooks;
161 
162 	if (ioctl(dev, PFILIOC_LISTHOOKS, &plh) != 0)
163 		err(1, "ioctl(PFILIOC_LISTHOOKS)");
164 
165 	if (plh.pio_nhooks > nhooks) {
166 		free(plh.pio_hooks);
167 		goto retry;
168 	}
169 
170 	printf("%16s %16s %8s\n", "Hook", "", "Type");
171 	for (i = 0; i < plh.pio_nhooks; i++) {
172 		printf("%16s:%-16s %8s\n", plh.pio_hooks[i].pio_module,
173 		    plh.pio_hooks[i].pio_ruleset,
174 		    typenames[plh.pio_hooks[i].pio_type]);
175 	}
176 }
177 
178 static void
179 hook(int argc, char *argv[])
180 {
181 	struct pfilioc_link req;
182 	int c;
183 	char *ruleset;
184 
185 	if (argv[0][0] == 'u')
186 		req.pio_flags = PFIL_UNLINK;
187 	else
188 		req.pio_flags = 0;
189 
190 	while ((c = getopt(argc, argv, "ioa")) != -1)
191 		switch (c) {
192 		case 'i':
193 			req.pio_flags |= PFIL_IN;
194 			break;
195 		case 'o':
196 			req.pio_flags |= PFIL_OUT;
197 			break;
198 		case 'a':
199 			req.pio_flags |= PFIL_APPEND;
200 			break;
201 		default:
202 			help();
203 		}
204 
205 	if (!PFIL_DIR(req.pio_flags))
206 		help();
207 
208 	argc -= optind;
209 	argv += optind;
210 
211 	if (argc != 2)
212 		help();
213 
214 	/* link mod:ruleset head */
215 	if ((ruleset = strchr(argv[0], ':')) == NULL)
216 		help();
217 	*ruleset = '\0';
218 	ruleset++;
219 
220 	strlcpy(req.pio_name, argv[1], sizeof(req.pio_name));
221 	strlcpy(req.pio_module, argv[0], sizeof(req.pio_module));
222 	strlcpy(req.pio_ruleset, ruleset, sizeof(req.pio_ruleset));
223 
224 	if (ioctl(dev, PFILIOC_LINK, &req) != 0)
225 		err(1, "ioctl(PFILIOC_LINK)");
226 }
227