1 /*
2  * f_tcindex.c		Traffic control index filter
3  *
4  * Written 1998,1999 by Werner Almesberger
5  */
6 
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <unistd.h>
10 #include <syslog.h>
11 #include <fcntl.h>
12 #include <string.h>
13 #include <netinet/in.h>
14 
15 #include "utils.h"
16 #include "tc_util.h"
17 
explain(void)18 static void explain(void)
19 {
20 	fprintf(stderr," Usage: ... tcindex [ hash SIZE ] [ mask MASK ]"
21 	    " [ shift SHIFT ]\n");
22 	fprintf(stderr,"                    [ pass_on | fall_through ]\n");
23 	fprintf(stderr,"                    [ classid CLASSID ] "
24 	    "[ police POLICE_SPEC ]\n");
25 }
26 
tcindex_parse_opt(struct filter_util * qu,char * handle,int argc,char ** argv,struct nlmsghdr * n)27 static int tcindex_parse_opt(struct filter_util *qu, char *handle, int argc,
28     char **argv, struct nlmsghdr *n)
29 {
30 	struct tcmsg *t = NLMSG_DATA(n);
31 	struct rtattr *tail;
32 	char *end;
33 
34 	if (handle) {
35 		t->tcm_handle = strtoul(handle,&end,0);
36 		if (*end) {
37 			fprintf(stderr, "Illegal filter ID\n");
38 			return -1;
39 		}
40 	}
41 	if (!argc) return 0;
42 	tail = NLMSG_TAIL(n);
43 	addattr_l(n,4096,TCA_OPTIONS,NULL,0);
44 	while (argc) {
45 		if (!strcmp(*argv,"hash")) {
46 			int hash;
47 
48 			NEXT_ARG();
49 			hash = strtoul(*argv,&end,0);
50 			if (*end || !hash || hash > 0x10000) {
51 				explain();
52 				return -1;
53 			}
54 			addattr_l(n,4096,TCA_TCINDEX_HASH,&hash,sizeof(hash));
55 		}
56 		else if (!strcmp(*argv,"mask")) {
57 			__u16 mask;
58 
59 			NEXT_ARG();
60 			mask = strtoul(*argv,&end,0);
61 			if (*end) {
62 				explain();
63 				return -1;
64 			}
65 			addattr_l(n,4096,TCA_TCINDEX_MASK,&mask,sizeof(mask));
66 		}
67 		else if (!strcmp(*argv,"shift")) {
68 			int shift;
69 
70 			NEXT_ARG();
71 			shift = strtoul(*argv,&end,0);
72 			if (*end) {
73 				explain();
74 				return -1;
75 			}
76 			addattr_l(n,4096,TCA_TCINDEX_SHIFT,&shift,
77 			    sizeof(shift));
78 		}
79 		else if (!strcmp(*argv,"fall_through")) {
80 			int value = 1;
81 
82 			addattr_l(n,4096,TCA_TCINDEX_FALL_THROUGH,&value,
83 			    sizeof(value));
84 		}
85 		else if (!strcmp(*argv,"pass_on")) {
86 			int value = 0;
87 
88 			addattr_l(n,4096,TCA_TCINDEX_FALL_THROUGH,&value,
89 			    sizeof(value));
90 		}
91 		else if (!strcmp(*argv,"classid")) {
92 			__u32 handle;
93 
94 			NEXT_ARG();
95 			if (get_tc_classid(&handle,*argv)) {
96 				fprintf(stderr, "Illegal \"classid\"\n");
97 				return -1;
98 			}
99 			addattr_l(n, 4096, TCA_TCINDEX_CLASSID, &handle, 4);
100 		}
101 		else if (!strcmp(*argv,"police")) {
102 			NEXT_ARG();
103 			if (parse_police(&argc, &argv, TCA_TCINDEX_POLICE, n)) {
104 				fprintf(stderr, "Illegal \"police\"\n");
105 				return -1;
106 			}
107 			continue;
108 		}
109 		else {
110 			explain();
111 			return -1;
112 		}
113 		argc--;
114 		argv++;
115 	}
116 	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
117 	return 0;
118 }
119 
120 
tcindex_print_opt(struct filter_util * qu,FILE * f,struct rtattr * opt,__u32 handle)121 static int tcindex_print_opt(struct filter_util *qu, FILE *f,
122      struct rtattr *opt, __u32 handle)
123 {
124 	struct rtattr *tb[TCA_TCINDEX_MAX+1];
125 
126 	if (opt == NULL)
127 		return 0;
128 
129 	parse_rtattr_nested(tb, TCA_TCINDEX_MAX, opt);
130 
131 	if (handle != ~0) fprintf(f,"handle 0x%04x ",handle);
132 	if (tb[TCA_TCINDEX_HASH]) {
133 		__u16 hash;
134 
135 		if (RTA_PAYLOAD(tb[TCA_TCINDEX_HASH]) < sizeof(hash))
136 			return -1;
137 		hash = rta_getattr_u16(tb[TCA_TCINDEX_HASH]);
138 		fprintf(f,"hash %d ",hash);
139 	}
140 	if (tb[TCA_TCINDEX_MASK]) {
141 		__u16 mask;
142 
143 		if (RTA_PAYLOAD(tb[TCA_TCINDEX_MASK]) < sizeof(mask))
144 			return -1;
145 		mask = rta_getattr_u16(tb[TCA_TCINDEX_MASK]);
146 		fprintf(f,"mask 0x%04x ",mask);
147 	}
148 	if (tb[TCA_TCINDEX_SHIFT]) {
149 		int shift;
150 
151 		if (RTA_PAYLOAD(tb[TCA_TCINDEX_SHIFT]) < sizeof(shift))
152 			return -1;
153 		shift = *(int *) RTA_DATA(tb[TCA_TCINDEX_SHIFT]);
154 		fprintf(f,"shift %d ",shift);
155 	}
156 	if (tb[TCA_TCINDEX_FALL_THROUGH]) {
157 		int fall_through;
158 
159 		if (RTA_PAYLOAD(tb[TCA_TCINDEX_FALL_THROUGH]) <
160 		    sizeof(fall_through))
161 			return -1;
162 		fall_through = *(int *) RTA_DATA(tb[TCA_TCINDEX_FALL_THROUGH]);
163 		fprintf(f,fall_through ? "fall_through " : "pass_on ");
164 	}
165 	if (tb[TCA_TCINDEX_CLASSID]) {
166 		SPRINT_BUF(b1);
167 		fprintf(f, "classid %s ",sprint_tc_classid(*(__u32 *)
168 		    RTA_DATA(tb[TCA_TCINDEX_CLASSID]), b1));
169 	}
170 	if (tb[TCA_TCINDEX_POLICE]) {
171 		fprintf(f, "\n");
172 		tc_print_police(f, tb[TCA_TCINDEX_POLICE]);
173 	}
174 	return 0;
175 }
176 
177 struct filter_util tcindex_filter_util = {
178 	.id = "tcindex",
179 	.parse_fopt = tcindex_parse_opt,
180 	.print_fopt = tcindex_print_opt,
181 };
182