blob: e3d0a2b118384e9549e9ff173939d76f6c30b33b [file] [log] [blame]
/*
* 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");
fprintf(stderr, "\n");
fprintf(stderr, "BPF use case:\n");
fprintf(stderr, " bytecode BPF_BYTECODE\n");
fprintf(stderr, " bytecode-file FILE\n");
fprintf(stderr, "\n");
fprintf(stderr, "eBPF use case:\n");
fprintf(stderr, " object-file FILE [ section ACT_NAME ] [ export UDS_FILE ]");
fprintf(stderr, " [ verbose ]\n");
fprintf(stderr, " object-pinned FILE\n");
fprintf(stderr, "\n");
fprintf(stderr, "Where BPF_BYTECODE := \'s,c t f k,c t f k,c t f k,...\'\n");
fprintf(stderr, "c,t,f,k and s are decimals; s denotes number of 4-tuples\n");
fprintf(stderr, "\n");
fprintf(stderr, "Where FILE points to a file containing the BPF_BYTECODE string,\n");
fprintf(stderr, "an ELF file containing eBPF map definitions and bytecode, or a\n");
fprintf(stderr, "pinned eBPF program.\n");
fprintf(stderr, "\n");
fprintf(stderr, "Where ACT_NAME refers to the section name containing the\n");
fprintf(stderr, "action (default \'%s\').\n", bpf_prog_to_default_section(bpf_type));
fprintf(stderr, "\n");
fprintf(stderr, "Where UDS_FILE points to a unix domain socket file in order\n");
fprintf(stderr, "to hand off control of all created eBPF maps to an agent.\n");
fprintf(stderr, "\n");
fprintf(stderr, "Where optionally INDEX points to an existing action, or\n");
fprintf(stderr, "explicitly specifies an action index upon creation.\n");
}
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 = NLMSG_TAIL(n);
addattr_l(n, MAX_MSG, tca_id, NULL, 0);
while (argc > 0) {
if (matches(*argv, "run") == 0) {
NEXT_ARG();
opt_bpf:
seen_run = true;
cfg.argc = argc;
cfg.argv = argv;
if (bpf_parse_common(bpf_type, &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));
tail->rta_len = (char *)NLMSG_TAIL(n) - (char *)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 dump_ok = 0;
if (arg == NULL)
return -1;
parse_rtattr_nested(tb, TCA_ACT_BPF_MAX, arg);
if (!tb[TCA_ACT_BPF_PARMS]) {
fprintf(f, "[NULL bpf parameters]");
return -1;
}
parm = RTA_DATA(tb[TCA_ACT_BPF_PARMS]);
fprintf(f, "bpf ");
if (tb[TCA_ACT_BPF_NAME])
fprintf(f, "%s ", rta_getattr_str(tb[TCA_ACT_BPF_NAME]));
if (tb[TCA_ACT_BPF_OPS] && tb[TCA_ACT_BPF_OPS_LEN]) {
bpf_print_ops(f, tb[TCA_ACT_BPF_OPS],
rta_getattr_u16(tb[TCA_ACT_BPF_OPS_LEN]));
fprintf(f, " ");
}
if (tb[TCA_ACT_BPF_ID])
dump_ok = bpf_dump_prog_info(f, rta_getattr_u32(tb[TCA_ACT_BPF_ID]));
if (!dump_ok && tb[TCA_ACT_BPF_TAG]) {
SPRINT_BUF(b);
fprintf(f, "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, "\n");
fprintf(f, "\tindex %u ref %d bind %d", parm->index, parm->refcnt,
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,
};