Konstantin Ananyev 5dba93ae5f bpf: add ability to load eBPF program from ELF object file
Introduce rte_bpf_elf_load() function to provide ability to
load eBPF program from ELF object file.
It also adds dependency on libelf.

Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Acked-by: Ferruh Yigit <ferruh.yigit@intel.com>
2018-05-12 00:35:20 +02:00

102 lines
1.9 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2018 Intel Corporation
*/
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdint.h>
#include <unistd.h>
#include <inttypes.h>
#include <rte_common.h>
#include <rte_log.h>
#include <rte_debug.h>
#include <rte_memory.h>
#include <rte_eal.h>
#include <rte_byteorder.h>
#include <rte_errno.h>
#include "bpf_impl.h"
static struct rte_bpf *
bpf_load(const struct rte_bpf_prm *prm)
{
uint8_t *buf;
struct rte_bpf *bpf;
size_t sz, bsz, insz, xsz;
xsz = prm->nb_xsym * sizeof(prm->xsym[0]);
insz = prm->nb_ins * sizeof(prm->ins[0]);
bsz = sizeof(bpf[0]);
sz = insz + xsz + bsz;
buf = mmap(NULL, sz, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (buf == MAP_FAILED)
return NULL;
bpf = (void *)buf;
bpf->sz = sz;
memcpy(&bpf->prm, prm, sizeof(bpf->prm));
memcpy(buf + bsz, prm->xsym, xsz);
memcpy(buf + bsz + xsz, prm->ins, insz);
bpf->prm.xsym = (void *)(buf + bsz);
bpf->prm.ins = (void *)(buf + bsz + xsz);
return bpf;
}
__rte_experimental struct rte_bpf *
rte_bpf_load(const struct rte_bpf_prm *prm)
{
struct rte_bpf *bpf;
int32_t rc;
if (prm == NULL || prm->ins == NULL) {
rte_errno = EINVAL;
return NULL;
}
bpf = bpf_load(prm);
if (bpf == NULL) {
rte_errno = ENOMEM;
return NULL;
}
rc = bpf_validate(bpf);
if (rc == 0) {
bpf_jit(bpf);
if (mprotect(bpf, bpf->sz, PROT_READ) != 0)
rc = -ENOMEM;
}
if (rc != 0) {
rte_bpf_destroy(bpf);
rte_errno = -rc;
return NULL;
}
return bpf;
}
__rte_experimental __attribute__ ((weak)) struct rte_bpf *
rte_bpf_elf_load(const struct rte_bpf_prm *prm, const char *fname,
const char *sname)
{
if (prm == NULL || fname == NULL || sname == NULL) {
rte_errno = EINVAL;
return NULL;
}
RTE_BPF_LOG(ERR, "%s() is not supported with current config\n"
"rebuild with libelf installed\n",
__func__);
rte_errno = ENOTSUP;
return NULL;
}