| // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) |
| /* Copyright (c) 2018 Facebook */ |
| |
| #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 <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; |
| }; |
| |
| static int libbpf_netlink_open(__u32 *nl_pid) |
| { |
| 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, NETLINK_ROUTE); |
| 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, 4096); |
| 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; |
| } |
| } |
| } |
| } |
| ret = 0; |
| done: |
| free(iov.iov_base); |
| return ret; |
| } |
| |
| static int libbpf_netlink_send_recv(struct libbpf_nla_req *req, |
| __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); |
| 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 __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, 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; |
| } |
| |
| 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 = {}; |
| int err; |
| |
| if (!OPTS_VALID(opts, bpf_xdp_query_opts)) |
| return libbpf_err(-EINVAL); |
| |
| if (xdp_flags & ~XDP_FLAGS_MASK) |
| return libbpf_err(-EINVAL); |
| |
| /* Check whether the single {HW,DRV,SKB} mode is set */ |
| 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, __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); |
| |
| 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); |
| |
| static int clsact_config(struct libbpf_nla_req *req) |
| { |
| 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 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; |
| 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); |
| if (ret < 0) |
| return ret; |
| |
| return libbpf_netlink_send_recv(&req, 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_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_obj_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, 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, 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, get_tc_info, NULL, &info); |
| if (ret < 0) |
| return libbpf_err(ret); |
| if (!info.processed) |
| return libbpf_err(-ENOENT); |
| return ret; |
| } |