samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnel

Add option to xdp1 and xdp_tx_iptunnel to insert xdp program in
SKB_MODE:
 - update set_link_xdp_fd to take a flags argument that is added to the
   RTM_SETLINK message

 - Add -S option to xdp1 and xdp_tx_iptunnel user code. When passed in
   XDP_FLAGS_SKB_MODE is set in the flags arg passed to set_link_xdp_fd

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index 0d449d8032d1ace67ad780f6d2ae86ce7fc6010e..d4433a47e6c3ae37bffdfd875e673fab5cc29552 100644 (file)
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -563,7 +563,7 @@ struct ksym *ksym_search(long key)
        return &syms[0];
 }
 
-int set_link_xdp_fd(int ifindex, int fd)
+int set_link_xdp_fd(int ifindex, int fd, int flags)
 {
        struct sockaddr_nl sa;
        int sock, seq = 0, len, ret = -1;
@@ -599,15 +599,28 @@ int set_link_xdp_fd(int ifindex, int fd)
        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 | 43/*IFLA_XDP*/;
+       nla->nla_len = NLA_HDRLEN;
 
-       nla_xdp = (struct nlattr *)((char *)nla + NLA_HDRLEN);
+       /* add XDP fd */
+       nla_xdp = (struct nlattr *)((char *)nla + nla->nla_len);
        nla_xdp->nla_type = 1/*IFLA_XDP_FD*/;
        nla_xdp->nla_len = NLA_HDRLEN + sizeof(int);
        memcpy((char *)nla_xdp + NLA_HDRLEN, &fd, sizeof(fd));
-       nla->nla_len = NLA_HDRLEN + nla_xdp->nla_len;
+       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 = 3/*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);
 

diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h
index 68f6b2d22507d706dc5d9f64d8fc121b5129ea1f..6bfd75ec6a16cc134eea37e521005df951f4e446 100644 (file)
--- a/samples/bpf/bpf_load.h
+++ b/samples/bpf/bpf_load.h
@@ -47,5 +47,5 @@ struct ksym {
 
 int load_kallsyms(void);
 struct ksym *ksym_search(long key);
-int set_link_xdp_fd(int ifindex, int fd);
+int set_link_xdp_fd(int ifindex, int fd, int flags);
 #endif

diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
index d2be65d1fd86ed199909bc6c68327f7d31e6b35a..deb05e630d842c9217879ead5ab9d7e90aaf69e3 100644 (file)
--- a/samples/bpf/xdp1_user.c
+++ b/samples/bpf/xdp1_user.c
@@ -5,6 +5,7 @@
  * License as published by the Free Software Foundation.
  */
 #include <linux/bpf.h>
+#include <linux/if_link.h>
 #include <assert.h>
 #include <errno.h>
 #include <signal.h>
@@ -12,16 +13,18 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <libgen.h>
 
 #include "bpf_load.h"
 #include "bpf_util.h"
 #include "libbpf.h"
 
 static int ifindex;
+static int flags;
 
 static void int_exit(int sig)
 {
-       set_link_xdp_fd(ifindex, -1);
+       set_link_xdp_fd(ifindex, -1, flags);
        exit(0);
 }
 
@@ -54,18 +57,39 @@ static void poll_stats(int interval)
        }
 }
 
-int main(int ac, char **argv)
+static void usage(const char *prog)
 {
-       char filename[256];
+       fprintf(stderr,
+               "usage: %s [OPTS] IFINDEX\n\n"
+               "OPTS:\n"
+               "    -S    use skb-mode\n",
+               prog);
+}
 
-       snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+int main(int argc, char **argv)
+{
+       const char *optstr = "S";
+       char filename[256];
+       int opt;
+
+       while ((opt = getopt(argc, argv, optstr)) != -1) {
+               switch (opt) {
+               case 'S':
+                       flags |= XDP_FLAGS_SKB_MODE;
+                       break;
+               default:
+                       usage(basename(argv[0]));
+                       return 1;
+               }
+       }
 
-       if (ac != 2) {
-               printf("usage: %s IFINDEX\n", argv[0]);
+       if (optind == argc) {
+               usage(basename(argv[0]));
                return 1;
        }
+       ifindex = strtoul(argv[optind], NULL, 0);
 
-       ifindex = strtoul(argv[1], NULL, 0);
+       snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 
        if (load_bpf_file(filename)) {
                printf("%s", bpf_log_buf);
@@ -79,7 +103,7 @@ int main(int ac, char **argv)
 
        signal(SIGINT, int_exit);
 
-       if (set_link_xdp_fd(ifindex, prog_fd[0]) < 0) {
+       if (set_link_xdp_fd(ifindex, prog_fd[0], flags) < 0) {
                printf("link set xdp fd failed\n");
                return 1;
        }

diff --git a/samples/bpf/xdp_tx_iptunnel_user.c b/samples/bpf/xdp_tx_iptunnel_user.c
index 70e192fc61aa4b9a317a1e8b11df0d36034cc877..cb2bda7b5346bcc8d98231beafe1196bcdfdf923 100644 (file)
--- a/samples/bpf/xdp_tx_iptunnel_user.c
+++ b/samples/bpf/xdp_tx_iptunnel_user.c
@@ -5,6 +5,7 @@
  * License as published by the Free Software Foundation.
  */
 #include <linux/bpf.h>
+#include <linux/if_link.h>
 #include <assert.h>
 #include <errno.h>
 #include <signal.h>
@@ -28,7 +29,7 @@ static int ifindex = -1;
 static void int_exit(int sig)
 {
        if (ifindex > -1)
-               set_link_xdp_fd(ifindex, -1);
+               set_link_xdp_fd(ifindex, -1, 0);
        exit(0);
 }
 
@@ -136,12 +137,13 @@ int main(int argc, char **argv)
 {
        unsigned char opt_flags[256] = {};
        unsigned int kill_after_s = 0;
-       const char *optstr = "i:a:p:s:d:m:T:P:h";
+       const char *optstr = "i:a:p:s:d:m:T:P:Sh";
        int min_port = 0, max_port = 0;
        struct iptnl_info tnl = {};
        struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
        struct vip vip = {};
        char filename[256];
+       int flags = 0;
        int opt;
        int i;
 
@@ -201,6 +203,9 @@ int main(int argc, char **argv)
                case 'T':
                        kill_after_s = atoi(optarg);
                        break;
+               case 'S':
+                       flags |= XDP_FLAGS_SKB_MODE;
+                       break;
                default:
                        usage(argv[0]);
                        return 1;
@@ -243,14 +248,14 @@ int main(int argc, char **argv)
                }
        }
 
-       if (set_link_xdp_fd(ifindex, prog_fd[0]) < 0) {
+       if (set_link_xdp_fd(ifindex, prog_fd[0], flags) < 0) {
                printf("link set xdp fd failed\n");
                return 1;
        }
 
        poll_stats(kill_after_s);
 
-       set_link_xdp_fd(ifindex, -1);
+       set_link_xdp_fd(ifindex, -1, flags);
 
        return 0;
 }