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 <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build
index 13a861135127f04e21590955de6802ea40380208..512b2c0ba0d2ec45bf63701dd5c5fc12bc68d16a 100644 (file)
--- 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 60aa4ca8b2c51b9c905c8b2ce1ed6329534711d4..3878a26a2071742b7c56bf65992034e4a618350e 100644 (file)
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -28,16 +28,8 @@
 #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
  * 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 (file)
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 <stdlib.h>
+#include <memory.h>
+#include <unistd.h>
+#include <linux/bpf.h>
+#include <linux/rtnetlink.h>
+#include <sys/socket.h>
+#include <errno.h>
+#include <time.h>
+
+#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;
+}