1 /*
2 * f_fw.c FW filter.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 */
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <unistd.h>
16 #include <syslog.h>
17 #include <fcntl.h>
18 #include <sys/socket.h>
19 #include <netinet/in.h>
20 #include <arpa/inet.h>
21 #include <string.h>
22 #include <linux/if.h> /* IFNAMSIZ */
23 #include "utils.h"
24 #include "tc_util.h"
25
explain(void)26 static void explain(void)
27 {
28 fprintf(stderr,
29 "Usage: ... fw [ classid CLASSID ] [ indev DEV ] [ action ACTION_SPEC ]\n");
30 fprintf(stderr,
31 " CLASSID := Push matching packets to the class identified by CLASSID with format X:Y\n");
32 fprintf(stderr,
33 " CLASSID is parsed as hexadecimal input.\n");
34 fprintf(stderr,
35 " DEV := specify device for incoming device classification.\n");
36 fprintf(stderr,
37 " ACTION_SPEC := Apply an action on matching packets.\n");
38 fprintf(stderr,
39 " NOTE: handle is represented as HANDLE[/FWMASK].\n");
40 fprintf(stderr, " FWMASK is 0xffffffff by default.\n");
41 }
42
fw_parse_opt(struct filter_util * qu,char * handle,int argc,char ** argv,struct nlmsghdr * n)43 static int fw_parse_opt(struct filter_util *qu, char *handle, int argc, char **argv, struct nlmsghdr *n)
44 {
45 struct tcmsg *t = NLMSG_DATA(n);
46 struct rtattr *tail;
47 __u32 mask = 0;
48 int mask_set = 0;
49
50 if (handle) {
51 char *slash;
52
53 if ((slash = strchr(handle, '/')) != NULL)
54 *slash = '\0';
55 if (get_u32(&t->tcm_handle, handle, 0)) {
56 fprintf(stderr, "Illegal \"handle\"\n");
57 return -1;
58 }
59 if (slash) {
60 if (get_u32(&mask, slash+1, 0)) {
61 fprintf(stderr, "Illegal \"handle\" mask\n");
62 return -1;
63 }
64 mask_set = 1;
65 }
66 }
67
68 if (argc == 0)
69 return 0;
70
71 tail = NLMSG_TAIL(n);
72 addattr_l(n, 4096, TCA_OPTIONS, NULL, 0);
73
74 if (mask_set)
75 addattr32(n, MAX_MSG, TCA_FW_MASK, mask);
76
77 while (argc > 0) {
78 if (matches(*argv, "classid") == 0 ||
79 matches(*argv, "flowid") == 0) {
80 unsigned int handle;
81
82 NEXT_ARG();
83 if (get_tc_classid(&handle, *argv)) {
84 fprintf(stderr, "Illegal \"classid\"\n");
85 return -1;
86 }
87 addattr_l(n, 4096, TCA_FW_CLASSID, &handle, 4);
88 } else if (matches(*argv, "police") == 0) {
89 NEXT_ARG();
90 if (parse_police(&argc, &argv, TCA_FW_POLICE, n)) {
91 fprintf(stderr, "Illegal \"police\"\n");
92 return -1;
93 }
94 continue;
95 } else if (matches(*argv, "action") == 0) {
96 NEXT_ARG();
97 if (parse_action(&argc, &argv, TCA_FW_ACT, n)) {
98 fprintf(stderr, "Illegal fw \"action\"\n");
99 return -1;
100 }
101 continue;
102 } else if (strcmp(*argv, "indev") == 0) {
103 char d[IFNAMSIZ+1] = {};
104
105 argc--;
106 argv++;
107 if (argc < 1) {
108 fprintf(stderr, "Illegal indev\n");
109 return -1;
110 }
111 strncpy(d, *argv, sizeof(d) - 1);
112 addattr_l(n, MAX_MSG, TCA_FW_INDEV, d, strlen(d) + 1);
113 } else if (strcmp(*argv, "help") == 0) {
114 explain();
115 return -1;
116 } else {
117 fprintf(stderr, "What is \"%s\"?\n", *argv);
118 explain();
119 return -1;
120 }
121 argc--; argv++;
122 }
123 tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
124 return 0;
125 }
126
fw_print_opt(struct filter_util * qu,FILE * f,struct rtattr * opt,__u32 handle)127 static int fw_print_opt(struct filter_util *qu, FILE *f, struct rtattr *opt, __u32 handle)
128 {
129 struct rtattr *tb[TCA_FW_MAX+1];
130
131 if (opt == NULL)
132 return 0;
133
134 parse_rtattr_nested(tb, TCA_FW_MAX, opt);
135
136 if (handle || tb[TCA_FW_MASK]) {
137 __u32 mark = 0, mask = 0;
138
139 if (handle)
140 mark = handle;
141 if (tb[TCA_FW_MASK] &&
142 (mask = rta_getattr_u32(tb[TCA_FW_MASK])) != 0xFFFFFFFF)
143 fprintf(f, "handle 0x%x/0x%x ", mark, mask);
144 else
145 fprintf(f, "handle 0x%x ", handle);
146 }
147
148 if (tb[TCA_FW_CLASSID]) {
149 SPRINT_BUF(b1);
150 fprintf(f, "classid %s ", sprint_tc_classid(rta_getattr_u32(tb[TCA_FW_CLASSID]), b1));
151 }
152
153 if (tb[TCA_FW_POLICE])
154 tc_print_police(f, tb[TCA_FW_POLICE]);
155 if (tb[TCA_FW_INDEV]) {
156 struct rtattr *idev = tb[TCA_FW_INDEV];
157
158 fprintf(f, "input dev %s ", rta_getattr_str(idev));
159 }
160
161 if (tb[TCA_FW_ACT]) {
162 fprintf(f, "\n");
163 tc_print_action(f, tb[TCA_FW_ACT], 0);
164 }
165 return 0;
166 }
167
168 struct filter_util fw_filter_util = {
169 .id = "fw",
170 .parse_fopt = fw_parse_opt,
171 .print_fopt = fw_print_opt,
172 };
173