#include <stdlib.h>
#include <memory.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <linux/bpf.h>
#include <linux/if_ether.h>
#include <linux/pkt_cls.h>
#include <linux/rtnetlink.h>
#include <linux/netdev.h>
#include <sys/socket.h>
#include <errno.h>
#include <time.h>
#include "bpf.h"
#include "libbpf.h"
#include "libbpf_internal.h"
#include "nlattr.h"
#ifndef SOL_NETLINK
#define SOL_NETLINK 270
#endif
typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb);
typedef int (*__dump_nlmsg_t)(struct nlmsghdr *nlmsg, libbpf_dump_nlmsg_t,
void *cookie);
struct xdp_link_info {
__u32 prog_id;
__u32 drv_prog_id;
__u32 hw_prog_id;
__u32 skb_prog_id;
__u8 attach_mode;
};
struct xdp_id_md {
int ifindex;
__u32 flags;
struct xdp_link_info info;
__u64 feature_flags;
};
struct xdp_features_md {
int ifindex;
__u32 xdp_zc_max_segs;
__u64 flags;
};
static int libbpf_netlink_open(__u32 *nl_pid, int proto)
{
struct sockaddr_nl sa;
socklen_t addrlen;
int one = 1, ret;
int sock;
memset(&sa, 0, sizeof(sa));
sa.nl_family = AF_NETLINK;
sock = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, proto);
if (sock < 0)
return -errno;
if (setsockopt(sock, SOL_NETLINK, NETLINK_EXT_ACK,
&one, sizeof(one)) < 0) {
pr_warn("Netlink error reporting not supported\n");
}
if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
ret = -errno;
goto cleanup;
}
addrlen = sizeof(sa);
if (getsockname(sock, (struct sockaddr *)&sa, &addrlen) < 0) {
ret = -errno;
goto cleanup;
}
if (addrlen != sizeof(sa)) {
ret = -LIBBPF_ERRNO__INTERNAL;
goto cleanup;
}
*nl_pid = sa.nl_pid;
return sock;
cleanup:
close(sock);
return ret;
}
static void libbpf_netlink_close(int sock)
{
close(sock);
}
enum {
NL_CONT,
NL_NEXT,
NL_DONE,
};
static int netlink_recvmsg(int sock, struct msghdr *mhdr, int flags)
{
int len;
do {
len = recvmsg(sock, mhdr, flags);
} while (len < 0 && (errno == EINTR || errno == EAGAIN));
if (len < 0)
return -errno;
return len;
}
static int alloc_iov(struct iovec *iov, int len)
{
void *nbuf;
nbuf = realloc(iov->iov_base, len);
if (!nbuf)
return -ENOMEM;
iov->iov_base = nbuf;
iov->iov_len = len;
return 0;
}
static int libbpf_netlink_recv(int sock, __u32 nl_pid, int seq,
__dump_nlmsg_t _fn, libbpf_dump_nlmsg_t fn,
void *cookie)
{
struct iovec iov = {};
struct msghdr mhdr = {
.msg_iov = &iov,
.msg_iovlen = 1,
};
bool multipart = true;
struct nlmsgerr *err;
struct nlmsghdr *nh;
int len, ret;
ret = alloc_iov(&iov, 8192);
if (ret)
goto done;
while (multipart) {
start:
multipart = false;
len = netlink_recvmsg(sock, &mhdr, MSG_PEEK | MSG_TRUNC);
if (len < 0) {
ret = len;
goto done;
}
if (len > iov.iov_len) {
ret = alloc_iov(&iov, len);
if (ret)
goto done;
}
len = netlink_recvmsg(sock, &mhdr, 0);
if (len < 0) {
ret = len;
goto done;
}
if (len == 0)
break;
for (nh = (struct nlmsghdr *)iov.iov_base; NLMSG_OK(nh, len);
nh = NLMSG_NEXT(nh, len)) {
if (nh->nlmsg_pid != nl_pid) {
ret = -LIBBPF_ERRNO__WRNGPID;
goto done;
}
if (nh->nlmsg_seq != seq) {
ret = -LIBBPF_ERRNO__INVSEQ;
goto done;
}
if (nh->nlmsg_flags & NLM_F_MULTI)
multipart = true;
switch (nh->nlmsg_type) {
case NLMSG_ERROR:
err = (struct nlmsgerr *)NLMSG_DATA(nh);
if (!err->error)
continue;
ret = err->error;
libbpf_nla_dump_errormsg(nh);
goto done;
case NLMSG_DONE:
ret = 0;
goto done;
default:
break;
}
if (_fn) {
ret = _fn(nh, fn, cookie);
switch (ret) {
case NL_CONT:
break;
case NL_NEXT:
goto start;
case NL_DONE:
ret = 0;
goto done;
default:
goto done;
}
}
}
if (len)
pr_warn("Invalid message or trailing data in Netlink response: %d bytes left\n", len);
}
ret = 0;
done:
free(iov.iov_base);
return ret;
}
static int libbpf_netlink_send_recv(struct libbpf_nla_req *req,
int proto, __dump_nlmsg_t parse_msg,
libbpf_dump_nlmsg_t parse_attr,
void *cookie)
{
__u32 nl_pid = 0;
int sock, ret;
sock = libbpf_netlink_open(&nl_pid, proto);
if (sock < 0)
return sock;
req->nh.nlmsg_pid = 0;
req->nh.nlmsg_seq = time(NULL);
if (send(sock, req, req->nh.nlmsg_len, 0) < 0) {
ret = -errno;
goto out;
}
ret = libbpf_netlink_recv(sock, nl_pid, req->nh.nlmsg_seq,
parse_msg, parse_attr, cookie);
out:
libbpf_netlink_close(sock);
return ret;
}
static int parse_genl_family_id(struct nlmsghdr *nh, libbpf_dump_nlmsg_t fn,
void *cookie)
{
struct genlmsghdr *gnl = NLMSG_DATA(nh);
struct nlattr *na = (struct nlattr *)((void *)gnl + GENL_HDRLEN);
struct nlattr *tb[CTRL_ATTR_FAMILY_ID + 1];
__u16 *id = cookie;
libbpf_nla_parse(tb, CTRL_ATTR_FAMILY_ID, na,
NLMSG_PAYLOAD(nh, sizeof(*gnl)), NULL);
if (!tb[CTRL_ATTR_FAMILY_ID])
return NL_CONT;
*id = libbpf_nla_getattr_u16(tb[CTRL_ATTR_FAMILY_ID]);
return NL_DONE;
}
static int libbpf_netlink_resolve_genl_family_id(const char *name,
__u16 len, __u16 *id)
{
struct libbpf_nla_req req = {
.nh.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN),
.nh.nlmsg_type = GENL_ID_CTRL,
.nh.nlmsg_flags = NLM_F_REQUEST,
.gnl.cmd = CTRL_CMD_GETFAMILY,
.gnl.version = 2,
};
int err;
err = nlattr_add(&req, CTRL_ATTR_FAMILY_NAME, name, len);
if (err < 0)
return err;
return libbpf_netlink_send_recv(&req, NETLINK_GENERIC,
parse_genl_family_id, NULL, id);
}
static int __bpf_set_link_xdp_fd_replace(int ifindex, int fd, int old_fd,
__u32 flags)
{
struct nlattr *nla;
int ret;
struct libbpf_nla_req req;
memset(&req, 0, sizeof(req));
req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
req.nh.nlmsg_type = RTM_SETLINK;
req.ifinfo.ifi_family = AF_UNSPEC;
req.ifinfo.ifi_index = ifindex;
nla = nlattr_begin_nested(&req, IFLA_XDP);
if (!nla)
return -EMSGSIZE;
ret = nlattr_add(&req, IFLA_XDP_FD, &fd, sizeof(fd));
if (ret < 0)
return ret;
if (flags) {
ret = nlattr_add(&req, IFLA_XDP_FLAGS, &flags, sizeof(flags));
if (ret < 0)
return ret;
}
if (flags & XDP_FLAGS_REPLACE) {
ret = nlattr_add(&req, IFLA_XDP_EXPECTED_FD, &old_fd,
sizeof(old_fd));
if (ret < 0)
return ret;
}
nlattr_end_nested(&req, nla);
return libbpf_netlink_send_recv(&req, NETLINK_ROUTE, NULL, NULL, NULL);
}
int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags, const struct bpf_xdp_attach_opts *opts)
{
int old_prog_fd, err;
if (!OPTS_VALID(opts, bpf_xdp_attach_opts))
return libbpf_err(-EINVAL);
old_prog_fd = OPTS_GET(opts, old_prog_fd, 0);
if (old_prog_fd)
flags |= XDP_FLAGS_REPLACE;
else
old_prog_fd = -1;
err = __bpf_set_link_xdp_fd_replace(ifindex, prog_fd, old_prog_fd, flags);
return libbpf_err(err);
}
int bpf_xdp_detach(int ifindex, __u32 flags, const struct bpf_xdp_attach_opts *opts)
{
return bpf_xdp_attach(ifindex, -1, flags, opts);
}
static int __dump_link_nlmsg(struct nlmsghdr *nlh,
libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie)
{
struct nlattr *tb[IFLA_MAX + 1], *attr;
struct ifinfomsg *ifi = NLMSG_DATA(nlh);
int len;
len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
attr = (struct nlattr *) ((void *) ifi + NLMSG_ALIGN(sizeof(*ifi)));
if (libbpf_nla_parse(tb, IFLA_MAX, attr, len, NULL) != 0)
return -LIBBPF_ERRNO__NLPARSE;
return dump_link_nlmsg(cookie, ifi, tb);
}
static int get_xdp_info(void *cookie, void *msg, struct nlattr **tb)
{
struct nlattr *xdp_tb[IFLA_XDP_MAX + 1];
struct xdp_id_md *xdp_id = cookie;
struct ifinfomsg *ifinfo = msg;
int ret;
if (xdp_id->ifindex && xdp_id->ifindex != ifinfo->ifi_index)
return 0;
if (!tb[IFLA_XDP])
return 0;
ret = libbpf_nla_parse_nested(xdp_tb, IFLA_XDP_MAX, tb[IFLA_XDP], NULL);
if (ret)
return ret;
if (!xdp_tb[IFLA_XDP_ATTACHED])
return 0;
xdp_id->info.attach_mode = libbpf_nla_getattr_u8(
xdp_tb[IFLA_XDP_ATTACHED]);
if (xdp_id->info.attach_mode == XDP_ATTACHED_NONE)
return 0;
if (xdp_tb[IFLA_XDP_PROG_ID])
xdp_id->info.prog_id = libbpf_nla_getattr_u32(
xdp_tb[IFLA_XDP_PROG_ID]);
if (xdp_tb[IFLA_XDP_SKB_PROG_ID])
xdp_id->info.skb_prog_id = libbpf_nla_getattr_u32(
xdp_tb[IFLA_XDP_SKB_PROG_ID]);
if (xdp_tb[IFLA_XDP_DRV_PROG_ID])
xdp_id->info.drv_prog_id = libbpf_nla_getattr_u32(
xdp_tb[IFLA_XDP_DRV_PROG_ID]);
if (xdp_tb[IFLA_XDP_HW_PROG_ID])
xdp_id->info.hw_prog_id = libbpf_nla_getattr_u32(
xdp_tb[IFLA_XDP_HW_PROG_ID]);
return 0;
}
static int parse_xdp_features(struct nlmsghdr *nh, libbpf_dump_nlmsg_t fn,
void *cookie)
{
struct genlmsghdr *gnl = NLMSG_DATA(nh);
struct nlattr *na = (struct nlattr *)((void *)gnl + GENL_HDRLEN);
struct nlattr *tb[NETDEV_CMD_MAX + 1];
struct xdp_features_md *md = cookie;
__u32 ifindex;
libbpf_nla_parse(tb, NETDEV_CMD_MAX, na,
NLMSG_PAYLOAD(nh, sizeof(*gnl)), NULL);
if (!tb[NETDEV_A_DEV_IFINDEX] || !tb[NETDEV_A_DEV_XDP_FEATURES])
return NL_CONT;
ifindex = libbpf_nla_getattr_u32(tb[NETDEV_A_DEV_IFINDEX]);
if (ifindex != md->ifindex)
return NL_CONT;
md->flags = libbpf_nla_getattr_u64(tb[NETDEV_A_DEV_XDP_FEATURES]);
if (tb[NETDEV_A_DEV_XDP_ZC_MAX_SEGS])
md->xdp_zc_max_segs =
libbpf_nla_getattr_u32(tb[NETDEV_A_DEV_XDP_ZC_MAX_SEGS]);
return NL_DONE;
}
int bpf_xdp_query(int ifindex, int xdp_flags, struct bpf_xdp_query_opts *opts)
{
struct libbpf_nla_req req = {
.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
.nh.nlmsg_type = RTM_GETLINK,
.nh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
.ifinfo.ifi_family = AF_PACKET,
};
struct xdp_id_md xdp_id = {};
struct xdp_features_md md = {
.ifindex = ifindex,
};
__u16 id;
int err;
if (!OPTS_VALID(opts, bpf_xdp_query_opts))
return libbpf_err(-EINVAL);
if (xdp_flags & ~XDP_FLAGS_MASK)
return libbpf_err(-EINVAL);
xdp_flags &= XDP_FLAGS_SKB_MODE | XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE;
if (xdp_flags & (xdp_flags - 1))
return libbpf_err(-EINVAL);
xdp_id.ifindex = ifindex;
xdp_id.flags = xdp_flags;
err = libbpf_netlink_send_recv(&req, NETLINK_ROUTE, __dump_link_nlmsg,
get_xdp_info, &xdp_id);
if (err)
return libbpf_err(err);
OPTS_SET(opts, prog_id, xdp_id.info.prog_id);
OPTS_SET(opts, drv_prog_id, xdp_id.info.drv_prog_id);
OPTS_SET(opts, hw_prog_id, xdp_id.info.hw_prog_id);
OPTS_SET(opts, skb_prog_id, xdp_id.info.skb_prog_id);
OPTS_SET(opts, attach_mode, xdp_id.info.attach_mode);
if (!OPTS_HAS(opts, feature_flags))
return 0;
err = libbpf_netlink_resolve_genl_family_id("netdev", sizeof("netdev"), &id);
if (err < 0) {
if (err == -ENOENT) {
opts->feature_flags = 0;
goto skip_feature_flags;
}
return libbpf_err(err);
}
memset(&req, 0, sizeof(req));
req.nh.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
req.nh.nlmsg_flags = NLM_F_REQUEST;
req.nh.nlmsg_type = id;
req.gnl.cmd = NETDEV_CMD_DEV_GET;
req.gnl.version = 2;
err = nlattr_add(&req, NETDEV_A_DEV_IFINDEX, &ifindex, sizeof(ifindex));
if (err < 0)
return libbpf_err(err);
err = libbpf_netlink_send_recv(&req, NETLINK_GENERIC,
parse_xdp_features, NULL, &md);
if (err)
return libbpf_err(err);
OPTS_SET(opts, feature_flags, md.flags);
OPTS_SET(opts, xdp_zc_max_segs, md.xdp_zc_max_segs);
skip_feature_flags:
return 0;
}
int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id)
{
LIBBPF_OPTS(bpf_xdp_query_opts, opts);
int ret;
ret = bpf_xdp_query(ifindex, flags, &opts);
if (ret)
return libbpf_err(ret);
flags &= XDP_FLAGS_MODES;
if (opts.attach_mode != XDP_ATTACHED_MULTI && !flags)
*prog_id = opts.prog_id;
else if (flags & XDP_FLAGS_DRV_MODE)
*prog_id = opts.drv_prog_id;
else if (flags & XDP_FLAGS_HW_MODE)
*prog_id = opts.hw_prog_id;
else if (flags & XDP_FLAGS_SKB_MODE)
*prog_id = opts.skb_prog_id;
else
*prog_id = 0;
return 0;
}
typedef int (*qdisc_config_t)(struct libbpf_nla_req *req, const struct bpf_tc_hook *hook);
static int clsact_config(struct libbpf_nla_req *req, const struct bpf_tc_hook *hook)
{
req->tc.tcm_parent = TC_H_CLSACT;
req->tc.tcm_handle = TC_H_MAKE(TC_H_CLSACT, 0);
return nlattr_add(req, TCA_KIND, "clsact", sizeof("clsact"));
}
static int qdisc_config(struct libbpf_nla_req *req, const struct bpf_tc_hook *hook)
{
const char *qdisc = OPTS_GET(hook, qdisc, NULL);
req->tc.tcm_parent = OPTS_GET(hook, parent, TC_H_ROOT);
req->tc.tcm_handle = OPTS_GET(hook, handle, 0);
return nlattr_add(req, TCA_KIND, qdisc, strlen(qdisc) + 1);
}
static int attach_point_to_config(struct bpf_tc_hook *hook,
qdisc_config_t *config)
{
switch (OPTS_GET(hook, attach_point, 0)) {
case BPF_TC_INGRESS:
case BPF_TC_EGRESS:
case BPF_TC_INGRESS | BPF_TC_EGRESS:
if (OPTS_GET(hook, parent, 0))
return -EINVAL;
*config = &clsact_config;
return 0;
case BPF_TC_CUSTOM:
return -EOPNOTSUPP;
case BPF_TC_QDISC:
*config = &qdisc_config;
return 0;
default:
return -EINVAL;
}
}
static int tc_get_tcm_parent(enum bpf_tc_attach_point attach_point,
__u32 *parent)
{
switch (attach_point) {
case BPF_TC_INGRESS:
case BPF_TC_EGRESS:
if (*parent)
return -EINVAL;
*parent = TC_H_MAKE(TC_H_CLSACT,
attach_point == BPF_TC_INGRESS ?
TC_H_MIN_INGRESS : TC_H_MIN_EGRESS);
break;
case BPF_TC_CUSTOM:
if (!*parent)
return -EINVAL;
break;
default:
return -EINVAL;
}
return 0;
}
static int tc_qdisc_modify(struct bpf_tc_hook *hook, int cmd, int flags)
{
qdisc_config_t config;
int ret;
struct libbpf_nla_req req;
ret = attach_point_to_config(hook, &config);
if (ret < 0)
return ret;
memset(&req, 0, sizeof(req));
req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags;
req.nh.nlmsg_type = cmd;
req.tc.tcm_family = AF_UNSPEC;
req.tc.tcm_ifindex = OPTS_GET(hook, ifindex, 0);
ret = config(&req, hook);
if (ret < 0)
return ret;
return libbpf_netlink_send_recv(&req, NETLINK_ROUTE, NULL, NULL, NULL);
}
static int tc_qdisc_create_excl(struct bpf_tc_hook *hook)
{
return tc_qdisc_modify(hook, RTM_NEWQDISC, NLM_F_CREATE | NLM_F_EXCL);
}
static int tc_qdisc_delete(struct bpf_tc_hook *hook)
{
return tc_qdisc_modify(hook, RTM_DELQDISC, 0);
}
int bpf_tc_hook_create(struct bpf_tc_hook *hook)
{
int ret;
if (!hook || !OPTS_VALID(hook, bpf_tc_hook) ||
OPTS_GET(hook, ifindex, 0) <= 0)
return libbpf_err(-EINVAL);
ret = tc_qdisc_create_excl(hook);
return libbpf_err(ret);
}
static int __bpf_tc_detach(const struct bpf_tc_hook *hook,
const struct bpf_tc_opts *opts,
const bool flush);
int bpf_tc_hook_destroy(struct bpf_tc_hook *hook)
{
if (!hook || !OPTS_VALID(hook, bpf_tc_hook) ||
OPTS_GET(hook, ifindex, 0) <= 0)
return libbpf_err(-EINVAL);
switch (OPTS_GET(hook, attach_point, 0)) {
case BPF_TC_INGRESS:
case BPF_TC_EGRESS:
return libbpf_err(__bpf_tc_detach(hook, NULL, true));
case BPF_TC_QDISC:
case BPF_TC_INGRESS | BPF_TC_EGRESS:
return libbpf_err(tc_qdisc_delete(hook));
case BPF_TC_CUSTOM:
return libbpf_err(-EOPNOTSUPP);
default:
return libbpf_err(-EINVAL);
}
}
struct bpf_cb_ctx {
struct bpf_tc_opts *opts;
bool processed;
};
static int __get_tc_info(void *cookie, struct tcmsg *tc, struct nlattr **tb,
bool unicast)
{
struct nlattr *tbb[TCA_BPF_MAX + 1];
struct bpf_cb_ctx *info = cookie;
if (!info || !info->opts)
return -EINVAL;
if (unicast && info->processed)
return -EINVAL;
if (!tb[TCA_OPTIONS])
return NL_CONT;
libbpf_nla_parse_nested(tbb, TCA_BPF_MAX, tb[TCA_OPTIONS], NULL);
if (!tbb[TCA_BPF_ID])
return -EINVAL;
OPTS_SET(info->opts, prog_id, libbpf_nla_getattr_u32(tbb[TCA_BPF_ID]));
OPTS_SET(info->opts, handle, tc->tcm_handle);
OPTS_SET(info->opts, priority, TC_H_MAJ(tc->tcm_info) >> 16);
info->processed = true;
return unicast ? NL_NEXT : NL_DONE;
}
static int get_tc_info(struct nlmsghdr *nh, libbpf_dump_nlmsg_t fn,
void *cookie)
{
struct tcmsg *tc = NLMSG_DATA(nh);
struct nlattr *tb[TCA_MAX + 1];
libbpf_nla_parse(tb, TCA_MAX,
(struct nlattr *)((void *)tc + NLMSG_ALIGN(sizeof(*tc))),
NLMSG_PAYLOAD(nh, sizeof(*tc)), NULL);
if (!tb[TCA_KIND])
return NL_CONT;
return __get_tc_info(cookie, tc, tb, nh->nlmsg_flags & NLM_F_ECHO);
}
static int tc_add_fd_and_name(struct libbpf_nla_req *req, int fd)
{
struct bpf_prog_info info;
__u32 info_len = sizeof(info);
char name[256];
int len, ret;
memset(&info, 0, info_len);
ret = bpf_prog_get_info_by_fd(fd, &info, &info_len);
if (ret < 0)
return ret;
ret = nlattr_add(req, TCA_BPF_FD, &fd, sizeof(fd));
if (ret < 0)
return ret;
len = snprintf(name, sizeof(name), "%s:[%u]", info.name, info.id);
if (len < 0)
return -errno;
if (len >= sizeof(name))
return -ENAMETOOLONG;
return nlattr_add(req, TCA_BPF_NAME, name, len + 1);
}
int bpf_tc_attach(const struct bpf_tc_hook *hook, struct bpf_tc_opts *opts)
{
__u32 protocol, bpf_flags, handle, priority, parent, prog_id, flags;
int ret, ifindex, attach_point, prog_fd;
struct bpf_cb_ctx info = {};
struct libbpf_nla_req req;
struct nlattr *nla;
if (!hook || !opts ||
!OPTS_VALID(hook, bpf_tc_hook) ||
!OPTS_VALID(opts, bpf_tc_opts))
return libbpf_err(-EINVAL);
ifindex = OPTS_GET(hook, ifindex, 0);
parent = OPTS_GET(hook, parent, 0);
attach_point = OPTS_GET(hook, attach_point, 0);
handle = OPTS_GET(opts, handle, 0);
priority = OPTS_GET(opts, priority, 0);
prog_fd = OPTS_GET(opts, prog_fd, 0);
prog_id = OPTS_GET(opts, prog_id, 0);
flags = OPTS_GET(opts, flags, 0);
if (ifindex <= 0 || !prog_fd || prog_id)
return libbpf_err(-EINVAL);
if (priority > UINT16_MAX)
return libbpf_err(-EINVAL);
if (flags & ~BPF_TC_F_REPLACE)
return libbpf_err(-EINVAL);
flags = (flags & BPF_TC_F_REPLACE) ? NLM_F_REPLACE : NLM_F_EXCL;
protocol = ETH_P_ALL;
memset(&req, 0, sizeof(req));
req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_CREATE |
NLM_F_ECHO | flags;
req.nh.nlmsg_type = RTM_NEWTFILTER;
req.tc.tcm_family = AF_UNSPEC;
req.tc.tcm_ifindex = ifindex;
req.tc.tcm_handle = handle;
req.tc.tcm_info = TC_H_MAKE(priority << 16, htons(protocol));
ret = tc_get_tcm_parent(attach_point, &parent);
if (ret < 0)
return libbpf_err(ret);
req.tc.tcm_parent = parent;
ret = nlattr_add(&req, TCA_KIND, "bpf", sizeof("bpf"));
if (ret < 0)
return libbpf_err(ret);
nla = nlattr_begin_nested(&req, TCA_OPTIONS);
if (!nla)
return libbpf_err(-EMSGSIZE);
ret = tc_add_fd_and_name(&req, prog_fd);
if (ret < 0)
return libbpf_err(ret);
bpf_flags = TCA_BPF_FLAG_ACT_DIRECT;
ret = nlattr_add(&req, TCA_BPF_FLAGS, &bpf_flags, sizeof(bpf_flags));
if (ret < 0)
return libbpf_err(ret);
nlattr_end_nested(&req, nla);
info.opts = opts;
ret = libbpf_netlink_send_recv(&req, NETLINK_ROUTE, get_tc_info, NULL,
&info);
if (ret < 0)
return libbpf_err(ret);
if (!info.processed)
return libbpf_err(-ENOENT);
return ret;
}
static int __bpf_tc_detach(const struct bpf_tc_hook *hook,
const struct bpf_tc_opts *opts,
const bool flush)
{
__u32 protocol = 0, handle, priority, parent, prog_id, flags;
int ret, ifindex, attach_point, prog_fd;
struct libbpf_nla_req req;
if (!hook ||
!OPTS_VALID(hook, bpf_tc_hook) ||
!OPTS_VALID(opts, bpf_tc_opts))
return -EINVAL;
ifindex = OPTS_GET(hook, ifindex, 0);
parent = OPTS_GET(hook, parent, 0);
attach_point = OPTS_GET(hook, attach_point, 0);
handle = OPTS_GET(opts, handle, 0);
priority = OPTS_GET(opts, priority, 0);
prog_fd = OPTS_GET(opts, prog_fd, 0);
prog_id = OPTS_GET(opts, prog_id, 0);
flags = OPTS_GET(opts, flags, 0);
if (ifindex <= 0 || flags || prog_fd || prog_id)
return -EINVAL;
if (priority > UINT16_MAX)
return -EINVAL;
if (!flush) {
if (!handle || !priority)
return -EINVAL;
protocol = ETH_P_ALL;
} else {
if (handle || priority)
return -EINVAL;
}
memset(&req, 0, sizeof(req));
req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
req.nh.nlmsg_type = RTM_DELTFILTER;
req.tc.tcm_family = AF_UNSPEC;
req.tc.tcm_ifindex = ifindex;
if (!flush) {
req.tc.tcm_handle = handle;
req.tc.tcm_info = TC_H_MAKE(priority << 16, htons(protocol));
}
ret = tc_get_tcm_parent(attach_point, &parent);
if (ret < 0)
return ret;
req.tc.tcm_parent = parent;
if (!flush) {
ret = nlattr_add(&req, TCA_KIND, "bpf", sizeof("bpf"));
if (ret < 0)
return ret;
}
return libbpf_netlink_send_recv(&req, NETLINK_ROUTE, NULL, NULL, NULL);
}
int bpf_tc_detach(const struct bpf_tc_hook *hook,
const struct bpf_tc_opts *opts)
{
int ret;
if (!opts)
return libbpf_err(-EINVAL);
ret = __bpf_tc_detach(hook, opts, false);
return libbpf_err(ret);
}
int bpf_tc_query(const struct bpf_tc_hook *hook, struct bpf_tc_opts *opts)
{
__u32 protocol, handle, priority, parent, prog_id, flags;
int ret, ifindex, attach_point, prog_fd;
struct bpf_cb_ctx info = {};
struct libbpf_nla_req req;
if (!hook || !opts ||
!OPTS_VALID(hook, bpf_tc_hook) ||
!OPTS_VALID(opts, bpf_tc_opts))
return libbpf_err(-EINVAL);
ifindex = OPTS_GET(hook, ifindex, 0);
parent = OPTS_GET(hook, parent, 0);
attach_point = OPTS_GET(hook, attach_point, 0);
handle = OPTS_GET(opts, handle, 0);
priority = OPTS_GET(opts, priority, 0);
prog_fd = OPTS_GET(opts, prog_fd, 0);
prog_id = OPTS_GET(opts, prog_id, 0);
flags = OPTS_GET(opts, flags, 0);
if (ifindex <= 0 || flags || prog_fd || prog_id ||
!handle || !priority)
return libbpf_err(-EINVAL);
if (priority > UINT16_MAX)
return libbpf_err(-EINVAL);
protocol = ETH_P_ALL;
memset(&req, 0, sizeof(req));
req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
req.nh.nlmsg_flags = NLM_F_REQUEST;
req.nh.nlmsg_type = RTM_GETTFILTER;
req.tc.tcm_family = AF_UNSPEC;
req.tc.tcm_ifindex = ifindex;
req.tc.tcm_handle = handle;
req.tc.tcm_info = TC_H_MAKE(priority << 16, htons(protocol));
ret = tc_get_tcm_parent(attach_point, &parent);
if (ret < 0)
return libbpf_err(ret);
req.tc.tcm_parent = parent;
ret = nlattr_add(&req, TCA_KIND, "bpf", sizeof("bpf"));
if (ret < 0)
return libbpf_err(ret);
info.opts = opts;
ret = libbpf_netlink_send_recv(&req, NETLINK_ROUTE, get_tc_info, NULL,
&info);
if (ret < 0)
return libbpf_err(ret);
if (!info.processed)
return libbpf_err(-ENOENT);
return ret;
}
