1 /*
2  * f_basic.c		Basic Classifier
3  *
4  *		This program is free software; you can distribute 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:	Thomas Graf <tgraf@suug.ch>
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>
23 
24 #include "utils.h"
25 #include "tc_util.h"
26 #include "m_ematch.h"
27 
explain(void)28 static void explain(void)
29 {
30 	fprintf(stderr, "Usage: ... basic [ match EMATCH_TREE ]\n");
31 	fprintf(stderr, "                 [ action ACTION_SPEC ] [ classid CLASSID ]\n");
32 	fprintf(stderr, "\n");
33 	fprintf(stderr, "Where: SELECTOR := SAMPLE SAMPLE ...\n");
34 	fprintf(stderr, "       FILTERID := X:Y:Z\n");
35 	fprintf(stderr, "       ACTION_SPEC := ... look at individual actions\n");
36 	fprintf(stderr, "\nNOTE: CLASSID is parsed as hexadecimal input.\n");
37 }
38 
basic_parse_opt(struct filter_util * qu,char * handle,int argc,char ** argv,struct nlmsghdr * n)39 static int basic_parse_opt(struct filter_util *qu, char *handle,
40 			   int argc, char **argv, struct nlmsghdr *n)
41 {
42 	struct tcmsg *t = NLMSG_DATA(n);
43 	struct rtattr *tail;
44 	long h = 0;
45 
46 	if (handle) {
47 		h = strtol(handle, NULL, 0);
48 		if (h == LONG_MIN || h == LONG_MAX) {
49 			fprintf(stderr, "Illegal handle \"%s\", must be numeric.\n",
50 			    handle);
51 			return -1;
52 		}
53 	}
54 	t->tcm_handle = h;
55 
56 	if (argc == 0)
57 		return 0;
58 
59 	tail = (struct rtattr *)(((void *)n)+NLMSG_ALIGN(n->nlmsg_len));
60 	addattr_l(n, MAX_MSG, TCA_OPTIONS, NULL, 0);
61 
62 	while (argc > 0) {
63 		if (matches(*argv, "match") == 0) {
64 			NEXT_ARG();
65 			if (parse_ematch(&argc, &argv, TCA_BASIC_EMATCHES, n)) {
66 				fprintf(stderr, "Illegal \"ematch\"\n");
67 				return -1;
68 			}
69 			continue;
70 		} else if (matches(*argv, "classid") == 0 ||
71 			   strcmp(*argv, "flowid") == 0) {
72 			unsigned int handle;
73 
74 			NEXT_ARG();
75 			if (get_tc_classid(&handle, *argv)) {
76 				fprintf(stderr, "Illegal \"classid\"\n");
77 				return -1;
78 			}
79 			addattr_l(n, MAX_MSG, TCA_BASIC_CLASSID, &handle, 4);
80 		} else if (matches(*argv, "action") == 0) {
81 			NEXT_ARG();
82 			if (parse_action(&argc, &argv, TCA_BASIC_ACT, n)) {
83 				fprintf(stderr, "Illegal \"action\"\n");
84 				return -1;
85 			}
86 			continue;
87 
88 		} else if (matches(*argv, "police") == 0) {
89 			NEXT_ARG();
90 			if (parse_police(&argc, &argv, TCA_BASIC_POLICE, n)) {
91 				fprintf(stderr, "Illegal \"police\"\n");
92 				return -1;
93 			}
94 			continue;
95 		} else if (strcmp(*argv, "help") == 0) {
96 			explain();
97 			return -1;
98 		} else {
99 			fprintf(stderr, "What is \"%s\"?\n", *argv);
100 			explain();
101 			return -1;
102 		}
103 		argc--; argv++;
104 	}
105 
106 	tail->rta_len = (((void *)n)+n->nlmsg_len) - (void *)tail;
107 	return 0;
108 }
109 
basic_print_opt(struct filter_util * qu,FILE * f,struct rtattr * opt,__u32 handle)110 static int basic_print_opt(struct filter_util *qu, FILE *f,
111 			   struct rtattr *opt, __u32 handle)
112 {
113 	struct rtattr *tb[TCA_BASIC_MAX+1];
114 
115 	if (opt == NULL)
116 		return 0;
117 
118 	parse_rtattr_nested(tb, TCA_BASIC_MAX, opt);
119 
120 	if (handle)
121 		fprintf(f, "handle 0x%x ", handle);
122 
123 	if (tb[TCA_BASIC_CLASSID]) {
124 		SPRINT_BUF(b1);
125 		fprintf(f, "flowid %s ",
126 			sprint_tc_classid(rta_getattr_u32(tb[TCA_BASIC_CLASSID]), b1));
127 	}
128 
129 	if (tb[TCA_BASIC_EMATCHES])
130 		print_ematch(f, tb[TCA_BASIC_EMATCHES]);
131 
132 	if (tb[TCA_BASIC_POLICE]) {
133 		fprintf(f, "\n");
134 		tc_print_police(f, tb[TCA_BASIC_POLICE]);
135 	}
136 
137 	if (tb[TCA_BASIC_ACT]) {
138 		tc_print_action(f, tb[TCA_BASIC_ACT], 0);
139 	}
140 
141 	return 0;
142 }
143 
144 struct filter_util basic_filter_util = {
145 	.id = "basic",
146 	.parse_fopt = basic_parse_opt,
147 	.print_fopt = basic_print_opt,
148 };
149