diff options
Diffstat (limited to 'tools/lib/bpf/netlink.c')
-rw-r--r-- | tools/lib/bpf/netlink.c | 173 |
1 files changed, 114 insertions, 59 deletions
diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c index 39f25e09b51e..35104580870c 100644 --- a/tools/lib/bpf/netlink.c +++ b/tools/lib/bpf/netlink.c @@ -27,6 +27,14 @@ 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; @@ -87,29 +95,75 @@ enum { 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; - char buf[4096]; int len, ret; + ret = alloc_iov(&iov, 4096); + if (ret) + goto done; + while (multipart) { start: multipart = false; - len = recv(sock, buf, sizeof(buf), 0); + 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 = -errno; + ret = len; goto done; } if (len == 0) break; - for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len); + 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; @@ -130,7 +184,8 @@ start: libbpf_nla_dump_errormsg(nh); goto done; case NLMSG_DONE: - return 0; + ret = 0; + goto done; default: break; } @@ -142,15 +197,17 @@ start: case NL_NEXT: goto start; case NL_DONE: - return 0; + ret = 0; + goto done; default: - return ret; + goto done; } } } } ret = 0; done: + free(iov.iov_base); return ret; } @@ -217,29 +274,26 @@ static int __bpf_set_link_xdp_fd_replace(int ifindex, int fd, int old_fd, return libbpf_netlink_send_recv(&req, NULL, NULL, NULL); } -int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags, - const struct bpf_xdp_set_link_opts *opts) +int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags, const struct bpf_xdp_attach_opts *opts) { - int old_fd = -1, ret; + int old_prog_fd, err; - if (!OPTS_VALID(opts, bpf_xdp_set_link_opts)) + if (!OPTS_VALID(opts, bpf_xdp_attach_opts)) return libbpf_err(-EINVAL); - if (OPTS_HAS(opts, old_fd)) { - old_fd = OPTS_GET(opts, old_fd, -1); + old_prog_fd = OPTS_GET(opts, old_prog_fd, 0); + if (old_prog_fd) flags |= XDP_FLAGS_REPLACE; - } + else + old_prog_fd = -1; - ret = __bpf_set_link_xdp_fd_replace(ifindex, fd, old_fd, flags); - return libbpf_err(ret); + err = __bpf_set_link_xdp_fd_replace(ifindex, prog_fd, old_prog_fd, flags); + return libbpf_err(err); } -int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags) +int bpf_xdp_detach(int ifindex, __u32 flags, const struct bpf_xdp_attach_opts *opts) { - int ret; - - ret = __bpf_set_link_xdp_fd_replace(ifindex, fd, 0, flags); - return libbpf_err(ret); + return bpf_xdp_attach(ifindex, -1, flags, opts); } static int __dump_link_nlmsg(struct nlmsghdr *nlh, @@ -303,70 +357,70 @@ static int get_xdp_info(void *cookie, void *msg, struct nlattr **tb) return 0; } -int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info, - size_t info_size, __u32 flags) +int bpf_xdp_query(int ifindex, int xdp_flags, struct bpf_xdp_query_opts *opts) { - struct xdp_id_md xdp_id = {}; - __u32 mask; - int ret; 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 (flags & ~XDP_FLAGS_MASK || !info_size) + if (xdp_flags & ~XDP_FLAGS_MASK) return libbpf_err(-EINVAL); /* Check whether the single {HW,DRV,SKB} mode is set */ - flags &= (XDP_FLAGS_SKB_MODE | XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE); - mask = flags - 1; - if (flags && flags & mask) + 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 = flags; + xdp_id.flags = xdp_flags; - ret = libbpf_netlink_send_recv(&req, __dump_link_nlmsg, + err = libbpf_netlink_send_recv(&req, __dump_link_nlmsg, get_xdp_info, &xdp_id); - if (!ret) { - size_t sz = min(info_size, sizeof(xdp_id.info)); + if (err) + return libbpf_err(err); - memcpy(info, &xdp_id.info, sz); - memset((void *) info + sz, 0, info_size - sz); - } + 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 libbpf_err(ret); + return 0; } -static __u32 get_xdp_id(struct xdp_link_info *info, __u32 flags) +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 (info->attach_mode != XDP_ATTACHED_MULTI && !flags) - return info->prog_id; - if (flags & XDP_FLAGS_DRV_MODE) - return info->drv_prog_id; - if (flags & XDP_FLAGS_HW_MODE) - return info->hw_prog_id; - if (flags & XDP_FLAGS_SKB_MODE) - return info->skb_prog_id; + 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; } -int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags) -{ - struct xdp_link_info info; - int ret; - - ret = bpf_get_link_xdp_info(ifindex, &info, sizeof(info), flags); - if (!ret) - *prog_id = get_xdp_id(&info, flags); - - return libbpf_err(ret); -} typedef int (*qdisc_config_t)(struct libbpf_nla_req *req); @@ -533,11 +587,12 @@ static int get_tc_info(struct nlmsghdr *nh, libbpf_dump_nlmsg_t fn, static int tc_add_fd_and_name(struct libbpf_nla_req *req, int fd) { - struct bpf_prog_info info = {}; + 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; |