diff options
Diffstat (limited to 'tools/lib/bpf/bpf.c')
| -rw-r--r-- | tools/lib/bpf/bpf.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 5128677e4117..592a58a2b681 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: LGPL-2.1 + /* * common eBPF ELF operations. * @@ -25,6 +27,16 @@ #include <asm/unistd.h> #include <linux/bpf.h> #include "bpf.h" +#include "libbpf.h" +#include "nlattr.h" +#include <linux/rtnetlink.h> +#include <linux/if_link.h> +#include <sys/socket.h> +#include <errno.h> + +#ifndef SOL_NETLINK +#define SOL_NETLINK 270 +#endif /* * When building perf, unistd.h is overridden. __NR_bpf is @@ -46,7 +58,9 @@ # endif #endif +#ifndef min #define min(x, y) ((x) < (y) ? (x) : (y)) +#endif static inline __u64 ptr_to_u64(const void *ptr) { @@ -413,3 +427,124 @@ int bpf_obj_get_info_by_fd(int prog_fd, void *info, __u32 *info_len) return err; } + +int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags) +{ + struct sockaddr_nl sa; + int sock, seq = 0, len, ret = -1; + char buf[4096]; + struct nlattr *nla, *nla_xdp; + struct { + struct nlmsghdr nh; + struct ifinfomsg ifinfo; + char attrbuf[64]; + } req; + struct nlmsghdr *nh; + struct nlmsgerr *err; + socklen_t addrlen; + int one = 1; + + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + + sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (sock < 0) { + return -errno; + } + + if (setsockopt(sock, SOL_NETLINK, NETLINK_EXT_ACK, + &one, sizeof(one)) < 0) { + fprintf(stderr, "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; + } + + 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.nh.nlmsg_pid = 0; + req.nh.nlmsg_seq = ++seq; + req.ifinfo.ifi_family = AF_UNSPEC; + req.ifinfo.ifi_index = ifindex; + + /* started nested attribute for XDP */ + nla = (struct nlattr *)(((char *)&req) + + NLMSG_ALIGN(req.nh.nlmsg_len)); + nla->nla_type = NLA_F_NESTED | IFLA_XDP; + nla->nla_len = NLA_HDRLEN; + + /* add XDP fd */ + nla_xdp = (struct nlattr *)((char *)nla + nla->nla_len); + nla_xdp->nla_type = IFLA_XDP_FD; + nla_xdp->nla_len = NLA_HDRLEN + sizeof(int); + memcpy((char *)nla_xdp + NLA_HDRLEN, &fd, sizeof(fd)); + nla->nla_len += nla_xdp->nla_len; + + /* if user passed in any flags, add those too */ + if (flags) { + nla_xdp = (struct nlattr *)((char *)nla + nla->nla_len); + nla_xdp->nla_type = IFLA_XDP_FLAGS; + nla_xdp->nla_len = NLA_HDRLEN + sizeof(flags); + memcpy((char *)nla_xdp + NLA_HDRLEN, &flags, sizeof(flags)); + nla->nla_len += nla_xdp->nla_len; + } + + req.nh.nlmsg_len += NLA_ALIGN(nla->nla_len); + + if (send(sock, &req, req.nh.nlmsg_len, 0) < 0) { + ret = -errno; + goto cleanup; + } + + len = recv(sock, buf, sizeof(buf), 0); + if (len < 0) { + ret = -errno; + goto cleanup; + } + + for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len); + nh = NLMSG_NEXT(nh, len)) { + if (nh->nlmsg_pid != sa.nl_pid) { + ret = -LIBBPF_ERRNO__WRNGPID; + goto cleanup; + } + if (nh->nlmsg_seq != seq) { + ret = -LIBBPF_ERRNO__INVSEQ; + goto cleanup; + } + switch (nh->nlmsg_type) { + case NLMSG_ERROR: + err = (struct nlmsgerr *)NLMSG_DATA(nh); + if (!err->error) + continue; + ret = err->error; + nla_dump_errormsg(nh); + goto cleanup; + case NLMSG_DONE: + break; + default: + break; + } + } + + ret = 0; + +cleanup: + close(sock); + return ret; +} |