summaryrefslogtreecommitdiffstats
path: root/tc/m_csum.c
blob: 21204e5bf7b6f857d811aba65496c8fd364705d1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * m_csum.c	checksum updating action
 *
 * Authors: Gregoire Baron <baronchon@n7mm.org>
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <linux/tc_act/tc_csum.h>

#include "utils.h"
#include "tc_util.h"

static void
explain(void)
{
	fprintf(stderr, "Usage: ... csum <UPDATE>\n"
			"Where: UPDATE := <TARGET> [<UPDATE>]\n"
			"       TARGET := { ip4h | icmp | igmp | tcp | udp | udplite | sctp | <SWEETS> }\n"
			"       SWEETS := { and | or | \'+\' }\n");
}

static void
usage(void)
{
	explain();
	exit(-1);
}

static int
parse_csum_args(int *argc_p, char ***argv_p, struct tc_csum *sel)
{
	int argc = *argc_p;
	char **argv = *argv_p;

	if (argc <= 0)
		return -1;

	while (argc > 0) {
		if ((matches(*argv, "iph") == 0) ||
		    (matches(*argv, "ip4h") == 0) ||
		    (matches(*argv, "ipv4h") == 0))
			sel->update_flags |= TCA_CSUM_UPDATE_FLAG_IPV4HDR;

		else if (matches(*argv, "icmp") == 0)
			sel->update_flags |= TCA_CSUM_UPDATE_FLAG_ICMP;

		else if (matches(*argv, "igmp") == 0)
			sel->update_flags |= TCA_CSUM_UPDATE_FLAG_IGMP;

		else if (matches(*argv, "tcp") == 0)
			sel->update_flags |= TCA_CSUM_UPDATE_FLAG_TCP;

		else if (matches(*argv, "udp") == 0)
			sel->update_flags |= TCA_CSUM_UPDATE_FLAG_UDP;

		else if (matches(*argv, "udplite") == 0)
			sel->update_flags |= TCA_CSUM_UPDATE_FLAG_UDPLITE;

		else if (matches(*argv, "sctp") == 0)
			sel->update_flags |= TCA_CSUM_UPDATE_FLAG_SCTP;

		else if ((matches(*argv, "and") == 0) ||
			 (matches(*argv, "or") == 0) ||
			 (matches(*argv, "+") == 0))
			; /* just ignore: ... csum iph and tcp or udp */
		else
			break;
		argc--;
		argv++;
	}

	*argc_p = argc;
	*argv_p = argv;

	return 0;
}

static int
parse_csum(const struct action_util *a, int *argc_p,
	   char ***argv_p, int tca_id, struct nlmsghdr *n)
{
	struct tc_csum sel = {};

	int argc = *argc_p;
	char **argv = *argv_p;
	int ok = 0;
	struct rtattr *tail;

	while (argc > 0) {
		if (matches(*argv, "csum") == 0) {
			NEXT_ARG();
			if (strcmp(*argv, "index") == 0) {
				goto skip_args;
			} else if (parse_csum_args(&argc, &argv, &sel)) {
				fprintf(stderr, "Illegal csum construct (%s)\n",
					*argv);
				explain();
				return -1;
			}
			ok++;
			continue;
		} else if (matches(*argv, "help") == 0) {
			usage();
		} else {
			break;
		}
	}

	if (!ok) {
		explain();
		return -1;
	}

	if (sel.update_flags == 0) {
		fprintf(stderr, "Illegal csum construct, empty <UPDATE> list\n");
		return -1;
	}

	parse_action_control_dflt(&argc, &argv, &sel.action, false, TC_ACT_OK);

	if (argc) {
		if (matches(*argv, "index") == 0) {
skip_args:
			NEXT_ARG();
			if (get_u32(&sel.index, *argv, 10)) {
				fprintf(stderr, "Illegal \"index\" (%s) <csum>\n",
					*argv);
				return -1;
			}
			argc--;
			argv++;
		}
	}

	tail = addattr_nest(n, MAX_MSG, tca_id);
	addattr_l(n, MAX_MSG, TCA_CSUM_PARMS, &sel, sizeof(sel));
	addattr_nest_end(n, tail);

	*argc_p = argc;
	*argv_p = argv;

	return 0;
}

static int
print_csum(const struct action_util *au, FILE *f, struct rtattr *arg)
{
	struct tc_csum *sel;

	struct rtattr *tb[TCA_CSUM_MAX + 1];

	char *uflag_1 = "";
	char *uflag_2 = "";
	char *uflag_3 = "";
	char *uflag_4 = "";
	char *uflag_5 = "";
	char *uflag_6 = "";
	char *uflag_7 = "";
	SPRINT_BUF(buf);

	int uflag_count = 0;

	print_string(PRINT_ANY, "kind", "%s ", "csum");
	if (arg == NULL)
		return 0;

	parse_rtattr_nested(tb, TCA_CSUM_MAX, arg);

	if (tb[TCA_CSUM_PARMS] == NULL) {
		fprintf(stderr, "Missing csum parameters\n");
		return -1;
	}
	sel = RTA_DATA(tb[TCA_CSUM_PARMS]);

	if (sel->update_flags & TCA_CSUM_UPDATE_FLAG_IPV4HDR) {
		uflag_1 = "iph";
		uflag_count++;
	}
	#define CSUM_UFLAG_BUFFER(flag_buffer, flag_value, flag_string)	\
		do {							\
			if (sel->update_flags & flag_value) {		\
				flag_buffer = uflag_count > 0 ?		\
					", " flag_string : flag_string; \
				uflag_count++;				\
			}						\
		} while (0)
	CSUM_UFLAG_BUFFER(uflag_2, TCA_CSUM_UPDATE_FLAG_ICMP, "icmp");
	CSUM_UFLAG_BUFFER(uflag_3, TCA_CSUM_UPDATE_FLAG_IGMP, "igmp");
	CSUM_UFLAG_BUFFER(uflag_4, TCA_CSUM_UPDATE_FLAG_TCP, "tcp");
	CSUM_UFLAG_BUFFER(uflag_5, TCA_CSUM_UPDATE_FLAG_UDP, "udp");
	CSUM_UFLAG_BUFFER(uflag_6, TCA_CSUM_UPDATE_FLAG_UDPLITE, "udplite");
	CSUM_UFLAG_BUFFER(uflag_7, TCA_CSUM_UPDATE_FLAG_SCTP, "sctp");
	if (!uflag_count) {
		uflag_1 = "?empty";
	}

	snprintf(buf, sizeof(buf), "%s%s%s%s%s%s%s",
		 uflag_1, uflag_2, uflag_3,
		 uflag_4, uflag_5, uflag_6, uflag_7);
	print_string(PRINT_ANY, "csum", "(%s) ", buf);

	print_action_control(f, "action ", sel->action, _SL_);
	print_uint(PRINT_ANY, "index", "\tindex %u", sel->index);
	print_int(PRINT_ANY, "ref", " ref %d", sel->refcnt);
	print_int(PRINT_ANY, "bind", " bind %d", sel->bindcnt);

	if (show_stats) {
		if (tb[TCA_CSUM_TM]) {
			struct tcf_t *tm = RTA_DATA(tb[TCA_CSUM_TM]);

			print_tm(f, tm);
		}
	}
	print_nl();

	return 0;
}

struct action_util csum_action_util = {
	.id = "csum",
	.parse_aopt = parse_csum,
	.print_aopt = print_csum,
};