1 /*
2  * Copyright (c) 2014 - 2018 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Bill Yuan <bycn82@dragonflybsd.org>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include "opt_ipfw.h"
36 #include "opt_inet.h"
37 #ifndef INET
38 #error IPFIREWALL3 requires INET.
39 #endif /* INET */
40 
41 #include <sys/param.h>
42 #include <sys/kernel.h>
43 #include <sys/malloc.h>
44 #include <sys/mbuf.h>
45 #include <sys/socketvar.h>
46 #include <sys/sysctl.h>
47 #include <sys/systimer.h>
48 
49 #include <net/ethernet.h>
50 #include <net/netmsg2.h>
51 #include <net/netisr2.h>
52 #include <net/route.h>
53 #include <net/if.h>
54 
55 #include <netinet/in_var.h>
56 #include <netinet/ip_var.h>
57 
58 #include <net/ipfw3/ip_fw.h>
59 #include <net/ipfw3_basic/ip_fw3_table.h>
60 
61 #include "ip_fw3_layer2.h"
62 
63 extern struct ipfw3_context      *fw3_ctx[MAXCPU];
64 
65 void
66 check_layer2(int *cmd_ctl, int *cmd_val, struct ip_fw_args **args,
67 		struct ip_fw **f, ipfw_insn *cmd, uint16_t ip_len)
68 {
69 	*cmd_val = ((*args)->eh != NULL);
70 	*cmd_ctl = IP_FW_CTL_NO;
71 }
72 
73 void
74 check_mac(int *cmd_ctl, int *cmd_val, struct ip_fw_args **args,
75 		struct ip_fw **f, ipfw_insn *cmd, uint16_t ip_len)
76 {
77 	*cmd_ctl = IP_FW_CTL_NO;
78 	if ((*args)->eh != NULL) {
79 		uint32_t *want = (uint32_t *)((ipfw_insn_mac *)cmd)->addr;
80 		uint32_t *mask = (uint32_t *)((ipfw_insn_mac *)cmd)->mask;
81 		uint32_t *hdr = (uint32_t *)(*args)->eh;
82 		*cmd_val =
83 			(want[0] == (hdr[0] & mask[0]) &&
84 			 want[1] == (hdr[1] & mask[1]) &&
85 			 want[2] == (hdr[2] & mask[2]));
86 	} else {
87 		*cmd_val = IP_FW_NOT_MATCH;
88 	}
89 }
90 
91 void
92 check_mac_from(int *cmd_ctl, int *cmd_val, struct ip_fw_args **args,
93 		struct ip_fw **f, ipfw_insn *cmd, uint16_t ip_len)
94 {
95 	*cmd_ctl = IP_FW_CTL_NO;
96 	if ((*args)->eh != NULL) {
97 		uint16_t *want = (uint16_t *)((ipfw_insn_mac *)cmd)->addr;
98 		uint16_t *mask = (uint16_t *)((ipfw_insn_mac *)cmd)->mask;
99 		uint16_t *hdr = (uint16_t *)(*args)->eh;
100 		*cmd_val =
101 			(want[3] == (hdr[3] & mask[3]) &&
102 			 want[4] == (hdr[4] & mask[4]) &&
103 			 want[5] == (hdr[5] & mask[5]));
104 	} else {
105 		*cmd_val = IP_FW_NOT_MATCH;
106 	}
107 }
108 
109 void
110 check_mac_from_lookup(int *cmd_ctl, int *cmd_val, struct ip_fw_args **args,
111 		struct ip_fw **f, ipfw_insn *cmd, uint16_t ip_len)
112 {
113         struct ipfw3_context *ctx = fw3_ctx[mycpuid];
114         struct ipfw3_table_context *table_ctx;
115         struct radix_node_head *rnh;
116         struct table_mac_entry *ent = NULL;
117 
118         table_ctx = ctx->table_ctx;
119         table_ctx += cmd->arg1;
120         rnh = table_ctx->node;
121 
122         *cmd_ctl = IP_FW_CTL_NO;
123         *cmd_val = IP_FW_NOT_MATCH;
124         if ((*args)->eh != NULL) {
125                 struct sockaddr sa;
126                 sa.sa_len = 8;
127                 strncpy(sa.sa_data, (*args)->eh->ether_shost, 6);
128                 ent = (struct table_mac_entry *)rnh->rnh_lookup(&sa, NULL, rnh);
129                 if (ent != NULL)
130                         *cmd_val = IP_FW_MATCH;
131         }
132 }
133 
134 void
135 check_mac_to(int *cmd_ctl, int *cmd_val, struct ip_fw_args **args,
136 		struct ip_fw **f, ipfw_insn *cmd, uint16_t ip_len)
137 {
138 	*cmd_ctl = IP_FW_CTL_NO;
139 	if ((*args)->eh != NULL) {
140 		uint16_t *want = (uint16_t *)((ipfw_insn_mac *)cmd)->addr;
141 		uint16_t *mask = (uint16_t *)((ipfw_insn_mac *)cmd)->mask;
142 		uint16_t *hdr = (uint16_t *)(*args)->eh;
143 		*cmd_val =
144 			(want[0] == (hdr[0] & mask[0]) &&
145 			 want[1] == (hdr[1] & mask[1]) &&
146 			 want[2] == (hdr[2] & mask[2]));
147 	} else {
148 		*cmd_val = IP_FW_NOT_MATCH;
149 	}
150 }
151 
152 void
153 check_mac_to_lookup(int *cmd_ctl, int *cmd_val, struct ip_fw_args **args,
154 		struct ip_fw **f, ipfw_insn *cmd, uint16_t ip_len)
155 {
156         struct ipfw3_context *ctx = fw3_ctx[mycpuid];
157         struct ipfw3_table_context *table_ctx;
158         struct radix_node_head *rnh;
159         struct table_mac_entry *ent = NULL;
160 
161         table_ctx = ctx->table_ctx;
162         table_ctx += cmd->arg1;
163         rnh = table_ctx->node;
164 
165         *cmd_ctl = IP_FW_CTL_NO;
166         *cmd_val = IP_FW_NOT_MATCH;
167         if ((*args)->eh != NULL) {
168                 struct sockaddr sa;
169                 sa.sa_len = 8;
170                 strncpy(sa.sa_data, (*args)->eh->ether_dhost, 6);
171                 ent = (struct table_mac_entry *)rnh->rnh_lookup(&sa, NULL, rnh);
172                 if (ent != NULL)
173                         *cmd_val = IP_FW_MATCH;
174         }
175 }
176 
177 static int
178 ip_fw3_layer2_init(void)
179 {
180 	ip_fw3_register_module(MODULE_LAYER2_ID, MODULE_LAYER2_NAME);
181 	ip_fw3_register_filter_funcs(MODULE_LAYER2_ID,
182 			O_LAYER2_LAYER2, (filter_func)check_layer2);
183 	ip_fw3_register_filter_funcs(MODULE_LAYER2_ID,
184 			O_LAYER2_MAC, (filter_func)check_mac);
185         ip_fw3_register_filter_funcs(MODULE_LAYER2_ID,
186 			O_LAYER2_MAC_SRC, (filter_func)check_mac_from);
187         ip_fw3_register_filter_funcs(MODULE_LAYER2_ID,
188 			O_LAYER2_MAC_DST, (filter_func)check_mac_to);
189         ip_fw3_register_filter_funcs(MODULE_LAYER2_ID,
190 			O_LAYER2_MAC_SRC_LOOKUP,
191 			(filter_func)check_mac_from_lookup);
192         ip_fw3_register_filter_funcs(MODULE_LAYER2_ID,
193 			O_LAYER2_MAC_DST_LOOKUP,
194 			(filter_func)check_mac_to_lookup);
195 	return 0;
196 }
197 
198 static int
199 ip_fw3_layer2_stop(void)
200 {
201 	return ip_fw3_unregister_module(MODULE_LAYER2_ID);
202 }
203 
204 static int
205 ipfw3_layer2_modevent(module_t mod, int type, void *data)
206 {
207 	switch (type) {
208 		case MOD_LOAD:
209 			return ip_fw3_layer2_init();
210 		case MOD_UNLOAD:
211 			return ip_fw3_layer2_stop();
212 		default:
213 			break;
214 	}
215 	return 0;
216 }
217 
218 static moduledata_t ipfw3_layer2_mod = {
219 	"ipfw3_layer2",
220 	ipfw3_layer2_modevent,
221 	NULL
222 };
223 DECLARE_MODULE(ipfw3_layer2, ipfw3_layer2_mod, SI_SUB_PROTO_END, SI_ORDER_ANY);
224 MODULE_DEPEND(ipfw3_layer2, ipfw3_basic, 1, 1, 1);
225 MODULE_VERSION(ipfw3_layer2, 1);
226