From f7010770fbac47b1fc9fb723b1d2019eb23c04f2 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Wed, 5 Sep 2018 16:58:04 -0700 Subject: [PATCH] tools/bpf: move bpf/lib netlink related functions into a new file There are no functionality change for this patch. In the subsequent patches, more netlink related library functions will be added and a separate file is better than cluttering bpf.c. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov --- tools/lib/bpf/Build | 2 +- tools/lib/bpf/bpf.c | 129 ------------------------------------- tools/lib/bpf/netlink.c | 165 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 166 insertions(+), 130 deletions(-) create mode 100644 tools/lib/bpf/netlink.c diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build index 13a8611..512b2c0b 100644 --- a/tools/lib/bpf/Build +++ b/tools/lib/bpf/Build @@ -1 +1 @@ -libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o +libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o netlink.o diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 60aa4ca..3878a26 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -28,16 +28,8 @@ #include #include "bpf.h" #include "libbpf.h" -#include "nlattr.h" -#include -#include -#include #include -#ifndef SOL_NETLINK -#define SOL_NETLINK 270 -#endif - /* * When building perf, unistd.h is overridden. __NR_bpf is * required to be defined explicitly. @@ -499,127 +491,6 @@ int bpf_raw_tracepoint_open(const char *name, int prog_fd) return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr)); } -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; -} - int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size, bool do_log) { diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c new file mode 100644 index 0000000..ccaa991 --- /dev/null +++ b/tools/lib/bpf/netlink.c @@ -0,0 +1,165 @@ +// SPDX-License-Identifier: LGPL-2.1 +/* Copyright (c) 2018 Facebook */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "bpf.h" +#include "libbpf.h" +#include "nlattr.h" + +#ifndef SOL_NETLINK +#define SOL_NETLINK 270 +#endif + +static int bpf_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, 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; + } + + *nl_pid = sa.nl_pid; + return sock; + +cleanup: + close(sock); + return ret; +} + +static int bpf_netlink_recv(int sock, __u32 nl_pid, int seq) +{ + struct nlmsgerr *err; + struct nlmsghdr *nh; + char buf[4096]; + int len, ret; + + while (1) { + len = recv(sock, buf, sizeof(buf), 0); + if (len < 0) { + ret = -errno; + goto done; + } + + for (nh = (struct nlmsghdr *)buf; 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; + } + 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 done; + case NLMSG_DONE: + return 0; + default: + break; + } + } + } + ret = 0; +done: + return ret; +} + +int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags) +{ + int sock, seq = 0, ret; + struct nlattr *nla, *nla_xdp; + struct { + struct nlmsghdr nh; + struct ifinfomsg ifinfo; + char attrbuf[64]; + } req; + __u32 nl_pid; + + sock = bpf_netlink_open(&nl_pid); + if (sock < 0) + return sock; + + 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; + } + ret = bpf_netlink_recv(sock, nl_pid, seq); + +cleanup: + close(sock); + return ret; +} -- 2.7.4