summaryrefslogtreecommitdiffstats
path: root/tc/m_bpf.c
blob: af5ba5ce45dc3dc314682d9766e8acf81cca6c74 (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
/*
 * m_bpf.c	BPF based action module
 *
 *              This program is free software; you can redistribute it and/or
 *              modify it under the terms of the GNU General Public License
 *              as published by the Free Software Foundation; either version
 *              2 of the License, or (at your option) any later version.
 *
 * Authors:     Jiri Pirko <jiri@resnulli.us>
 *              Daniel Borkmann <daniel@iogearbox.net>
 */

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

#include <linux/bpf.h>
#include <linux/tc_act/tc_bpf.h>

#include "utils.h"

#include "tc_util.h"
#include "bpf_util.h"

static const enum bpf_prog_type bpf_type = BPF_PROG_TYPE_SCHED_ACT;

static void explain(void)
{
	fprintf(stderr,
		"Usage: ... bpf ... [ index INDEX ]\n"
		"\n"
		"BPF use case:\n"
		" bytecode BPF_BYTECODE\n"
		" bytecode-file FILE\n"
		"\n"
		"eBPF use case:\n"
		" object-file FILE [ section ACT_NAME ] [ export UDS_FILE ]"
		" [ verbose ]\n"
		" object-pinned FILE\n"
		"\n"
		"Where BPF_BYTECODE := \'s,c t f k,c t f k,c t f k,...\'\n"
		"c,t,f,k and s are decimals; s denotes number of 4-tuples\n"
		"\n"
		"Where FILE points to a file containing the BPF_BYTECODE string,\n"
		"an ELF file containing eBPF map definitions and bytecode, or a\n"
		"pinned eBPF program.\n"
		"\n"
		"Where ACT_NAME refers to the section name containing the\n"
		"action (default \'%s\').\n"
		"\n"
		"Where UDS_FILE points to a unix domain socket file in order\n"
		"to hand off control of all created eBPF maps to an agent.\n"
		"\n"
		"Where optionally INDEX points to an existing action, or\n"
		"explicitly specifies an action index upon creation.\n",
		bpf_prog_to_default_section(bpf_type));
}

static void bpf_cbpf_cb(void *nl, const struct sock_filter *ops, int ops_len)
{
	addattr16(nl, MAX_MSG, TCA_ACT_BPF_OPS_LEN, ops_len);
	addattr_l(nl, MAX_MSG, TCA_ACT_BPF_OPS, ops,
		  ops_len * sizeof(struct sock_filter));
}

static void bpf_ebpf_cb(void *nl, int fd, const char *annotation)
{
	addattr32(nl, MAX_MSG, TCA_ACT_BPF_FD, fd);
	addattrstrz(nl, MAX_MSG, TCA_ACT_BPF_NAME, annotation);
}

static const struct bpf_cfg_ops bpf_cb_ops = {
	.cbpf_cb = bpf_cbpf_cb,
	.ebpf_cb = bpf_ebpf_cb,
};

static int bpf_parse_opt(struct action_util *a, int *ptr_argc, char ***ptr_argv,
			 int tca_id, struct nlmsghdr *n)
{
	const char *bpf_obj = NULL, *bpf_uds_name = NULL;
	struct tc_act_bpf parm = {};
	struct bpf_cfg_in cfg = {};
	bool seen_run = false;
	struct rtattr *tail;
	int argc, ret = 0;
	char **argv;

	argv = *ptr_argv;
	argc = *ptr_argc;

	if (matches(*argv, "bpf") != 0)
		return -1;

	NEXT_ARG();

	tail = addattr_nest(n, MAX_MSG, tca_id);

	while (argc > 0) {
		if (matches(*argv, "run") == 0) {
			NEXT_ARG();

			if (seen_run)
				duparg("run", *argv);
opt_bpf:
			seen_run = true;
			cfg.type = bpf_type;
			cfg.argc = argc;
			cfg.argv = argv;

			if (bpf_parse_and_load_common(&cfg, &bpf_cb_ops, n))
				return -1;

			argc = cfg.argc;
			argv = cfg.argv;

			bpf_obj = cfg.object;
			bpf_uds_name = cfg.uds;
		} else if (matches(*argv, "help") == 0) {
			explain();
			return -1;
		} else if (matches(*argv, "index") == 0) {
			break;
		} else {
			if (!seen_run)
				goto opt_bpf;
			break;
		}

		NEXT_ARG_FWD();
	}

	parse_action_control_dflt(&argc, &argv, &parm.action,
				  false, TC_ACT_PIPE);

	if (argc) {
		if (matches(*argv, "index") == 0) {
			NEXT_ARG();
			if (get_u32(&parm.index, *argv, 10)) {
				fprintf(stderr, "bpf: Illegal \"index\"\n");
				return -1;
			}

			NEXT_ARG_FWD();
		}
	}

	addattr_l(n, MAX_MSG, TCA_ACT_BPF_PARMS, &parm, sizeof(parm));
	addattr_nest_end(n, tail);

	if (bpf_uds_name)
		ret = bpf_send_map_fds(bpf_uds_name, bpf_obj);

	*ptr_argc = argc;
	*ptr_argv = argv;

	return ret;
}

static int bpf_print_opt(struct action_util *au, FILE *f, struct rtattr *arg)
{
	struct rtattr *tb[TCA_ACT_BPF_MAX + 1];
	struct tc_act_bpf *parm;
	int d_ok = 0;

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

	parse_rtattr_nested(tb, TCA_ACT_BPF_MAX, arg);

	if (!tb[TCA_ACT_BPF_PARMS]) {
		fprintf(stderr, "Missing bpf parameters\n");
		return -1;
	}

	parm = RTA_DATA(tb[TCA_ACT_BPF_PARMS]);

	if (tb[TCA_ACT_BPF_NAME])
		print_string(PRINT_ANY, "bpf_name", "%s ",
			     rta_getattr_str(tb[TCA_ACT_BPF_NAME]));
	if (tb[TCA_ACT_BPF_OPS] && tb[TCA_ACT_BPF_OPS_LEN]) {
		bpf_print_ops(tb[TCA_ACT_BPF_OPS],
			      rta_getattr_u16(tb[TCA_ACT_BPF_OPS_LEN]));
		print_string(PRINT_FP, NULL, "%s", " ");
	}

	if (tb[TCA_ACT_BPF_ID])
		d_ok = bpf_dump_prog_info(f,
					  rta_getattr_u32(tb[TCA_ACT_BPF_ID]));
	if (!d_ok && tb[TCA_ACT_BPF_TAG]) {
		SPRINT_BUF(b);

		print_string(PRINT_ANY, "tag", "tag %s ",
			     hexstring_n2a(RTA_DATA(tb[TCA_ACT_BPF_TAG]),
			     RTA_PAYLOAD(tb[TCA_ACT_BPF_TAG]),
			     b, sizeof(b)));
	}

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

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

			print_tm(f, tm);
		}
	}

	fprintf(f, "\n ");
	return 0;
}

struct action_util bpf_action_util = {
	.id		= "bpf",
	.parse_aopt	= bpf_parse_opt,
	.print_aopt	= bpf_print_opt,
};