erspan: Add flow-based erspan options

The patch add supports for flow-based erspan options.
The erspan_ver, erspan_idx, erspan_dir, and erspan_hwid can be
set as "flow" so that its value is set by the openflow rule,
instead of statically configured at port creation time.

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

3 files changed, 123 insertions, 40 deletions

diff --git a/lib/netdev-native-tnl.c b/lib/netdev-native-tnl.c
index c70811eaf..c97491ed0 100644
--- a/lib/netdev-native-tnl.c
+++ b/lib/netdev-native-tnl.c
@@ -628,6 +628,7 @@ netdev_erspan_build_header(const struct netdev *netdev,
     struct erspan_base_hdr *ersh;
     unsigned int hlen;
     uint32_t tun_id;
+    int erspan_ver;
     uint16_t sid;
 
     /* XXX: RCUfy tnl_cfg. */
@@ -645,7 +646,15 @@ netdev_erspan_build_header(const struct netdev *netdev,
         sid = (uint16_t) tun_id;
     }
 
-    if (tnl_cfg->erspan_ver == 1) {
+    if (tnl_cfg->erspan_ver_flow) {
+        erspan_ver = params->flow->tunnel.erspan_ver;
+    } else {
+        erspan_ver = tnl_cfg->erspan_ver;
+    }
+
+    if (erspan_ver == 1) {
+        ovs_be32 *index;
+
         greh->protocol = htons(ETH_TYPE_ERSPAN1);
         greh->flags = htons(GRE_SEQ);
         ersh->ver = 1;
@@ -654,19 +663,38 @@ netdev_erspan_build_header(const struct netdev *netdev,
         put_16aligned_be32(ALIGNED_CAST(ovs_16aligned_be32 *, ersh + 1),
                            htonl(tnl_cfg->erspan_idx));
 
+        index = (ovs_be32 *)(ersh + 1);
+
+        if (tnl_cfg->erspan_idx_flow) {
+            *index = htonl(params->flow->tunnel.erspan_idx);
+        } else {
+            *index = htonl(tnl_cfg->erspan_idx);
+        }
+
         hlen = ERSPAN_GREHDR_LEN + sizeof *ersh + ERSPAN_V1_MDSIZE;
-    } else if (tnl_cfg->erspan_ver == 2) {
+    } else if (erspan_ver == 2) {
+        struct erspan_md2 *md2 = ALIGNED_CAST(struct erspan_md2 *, ersh + 1);
+
         greh->protocol = htons(ETH_TYPE_ERSPAN2);
         greh->flags = htons(GRE_SEQ);
         ersh->ver = 2;
         set_sid(ersh, sid);
 
-        struct erspan_md2 *md2 = ALIGNED_CAST(struct erspan_md2 *, ersh + 1);
         md2->sgt = 0; /* security group tag */
         md2->gra = 0;
         put_16aligned_be32(&md2->timestamp, 0);
-        set_hwid(md2, tnl_cfg->erspan_hwid);
-        md2->dir = tnl_cfg->erspan_dir;
+
+        if (tnl_cfg->erspan_hwid_flow) {
+            set_hwid(md2, params->flow->tunnel.erspan_hwid);
+        } else {
+            set_hwid(md2, tnl_cfg->erspan_hwid);
+        }
+
+        if (tnl_cfg->erspan_dir_flow) {
+            md2->dir = params->flow->tunnel.erspan_dir;
+        } else {
+            md2->dir = tnl_cfg->erspan_dir;
+        }
 
         hlen = ERSPAN_GREHDR_LEN + sizeof *ersh + ERSPAN_V2_MDSIZE;
     } else {
diff --git a/lib/netdev-vport.c b/lib/netdev-vport.c
index 805f130d4..1dae7e031 100644
--- a/lib/netdev-vport.c
+++ b/lib/netdev-vport.c
@@ -545,36 +545,63 @@ set_tunnel_config(struct netdev *dev_, const struct smap *args, char **errp)
             tnl_cfg.egress_pkt_mark = strtoul(node->value, NULL, 10);
             tnl_cfg.set_egress_pkt_mark = true;
         } else if (!strcmp(node->key, "erspan_idx")) {
-            tnl_cfg.erspan_idx = strtol(node->value, NULL, 16);
-            if (tnl_cfg.erspan_idx & ~ERSPAN_IDX_MASK) {
-                ds_put_format(&errors, "%s: invalid erspan index: %s\n",
-                              name, node->value);
-                err = EINVAL;
-                goto out;
+            if (!strcmp(node->value, "flow")) {
+                tnl_cfg.erspan_idx_flow = true;
+            } else {
+                tnl_cfg.erspan_idx_flow = false;
+                tnl_cfg.erspan_idx = strtol(node->value, NULL, 16);
+
+                if (tnl_cfg.erspan_idx & ~ERSPAN_IDX_MASK) {
+                    ds_put_format(&errors, "%s: invalid erspan index: %s\n",
+                                  name, node->value);
+                    err = EINVAL;
+                    goto out;
+                }
             }
         } else if (!strcmp(node->key, "erspan_ver")) {
-            tnl_cfg.erspan_ver = atoi(node->value);
-            if (tnl_cfg.erspan_ver != 1 && tnl_cfg.erspan_ver != 2) {
-                ds_put_format(&errors, "%s: invalid erspan version: %s\n",
-                              name, node->value);
-                err = EINVAL;
-                goto out;
+            if (!strcmp(node->value, "flow")) {
+                tnl_cfg.erspan_ver_flow = true;
+                tnl_cfg.erspan_idx_flow = true;
+                tnl_cfg.erspan_dir_flow = true;
+                tnl_cfg.erspan_hwid_flow = true;
+            } else {
+                tnl_cfg.erspan_ver_flow = false;
+                tnl_cfg.erspan_ver = atoi(node->value);
+
+                if (tnl_cfg.erspan_ver != 1 && tnl_cfg.erspan_ver != 2) {
+                    ds_put_format(&errors, "%s: invalid erspan version: %s\n",
+                                  name, node->value);
+                    err = EINVAL;
+                    goto out;
+                }
             }
         } else if (!strcmp(node->key, "erspan_dir")) {
-            tnl_cfg.erspan_dir = atoi(node->value);
-            if (tnl_cfg.erspan_dir != 0 && tnl_cfg.erspan_dir != 1) {
-                ds_put_format(&errors, "%s: invalid erspan direction: %s\n",
-                              name, node->value);
-                err = EINVAL;
-                goto out;
+            if (!strcmp(node->value, "flow")) {
+                tnl_cfg.erspan_dir_flow = true;
+            } else {
+                tnl_cfg.erspan_dir_flow = false;
+                tnl_cfg.erspan_dir = atoi(node->value);
+
+                if (tnl_cfg.erspan_dir != 0 && tnl_cfg.erspan_dir != 1) {
+                    ds_put_format(&errors, "%s: invalid erspan direction: %s\n",
+                                  name, node->value);
+                    err = EINVAL;
+                    goto out;
+                }
             }
         } else if (!strcmp(node->key, "erspan_hwid")) {
-            tnl_cfg.erspan_hwid = strtol(node->value, NULL, 16);
-            if (tnl_cfg.erspan_hwid & ~(ERSPAN_HWID_MASK >> 4)) {
-                ds_put_format(&errors, "%s: invalid erspan hardware ID: %s\n",
-                              name, node->value);
-                err = EINVAL;
-                goto out;
+            if (!strcmp(node->value, "flow")) {
+                tnl_cfg.erspan_hwid_flow = true;
+            } else {
+                tnl_cfg.erspan_hwid_flow = false;
+                tnl_cfg.erspan_hwid = strtol(node->value, NULL, 16);
+
+                if (tnl_cfg.erspan_hwid & ~(ERSPAN_HWID_MASK >> 4)) {
+                    ds_put_format(&errors, "%s: invalid erspan hardware ID: %s\n",
+                                  name, node->value);
+                    err = EINVAL;
+                    goto out;
+                }
             }
         } else {
             ds_put_format(&errors, "%s: unknown %s argument '%s'\n", name,
@@ -767,17 +794,40 @@ get_tunnel_config(const struct netdev *dev, struct smap *args)
                         "%"PRIu32, tnl_cfg.egress_pkt_mark);
     }
 
-    if (tnl_cfg.erspan_idx) {
-        smap_add_format(args, "erspan_idx", "0x%x", tnl_cfg.erspan_idx);
-    }
-    if (tnl_cfg.erspan_ver) {
-        smap_add_format(args, "erspan_ver", "%d", tnl_cfg.erspan_ver);
-    }
-    if (tnl_cfg.erspan_dir) {
-        smap_add_format(args, "erspan_dir", "%d", tnl_cfg.erspan_dir);
-    }
-    if (tnl_cfg.erspan_hwid) {
-        smap_add_format(args, "erspan_hwid", "0x%x", tnl_cfg.erspan_hwid);
+    if (!strcmp("erspan", type) || !strcmp("ip6erspan", type)) {
+        if (tnl_cfg.erspan_ver_flow) {
+            /* since version number is not determined,
+             * assume print all other as flow
+             */
+            smap_add(args, "erspan_ver", "flow");
+            smap_add(args, "erspan_idx", "flow");
+            smap_add(args, "erspan_dir", "flow");
+            smap_add(args, "erspan_hwid", "flow");
+        } else {
+            smap_add_format(args, "erspan_ver", "%d", tnl_cfg.erspan_ver);
+
+            if (tnl_cfg.erspan_ver == 1) {
+                if (tnl_cfg.erspan_idx_flow) {
+                    smap_add(args, "erspan_idx", "flow");
+                } else {
+                    smap_add_format(args, "erspan_idx", "0x%x",
+                                    tnl_cfg.erspan_idx);
+                }
+            } else if (tnl_cfg.erspan_ver == 2) {
+                if (tnl_cfg.erspan_dir_flow) {
+                    smap_add(args, "erspan_dir", "flow");
+                } else {
+                    smap_add_format(args, "erspan_dir", "%d",
+                                    tnl_cfg.erspan_dir);
+                }
+                if (tnl_cfg.erspan_hwid_flow) {
+                    smap_add(args, "erspan_hwid", "flow");
+                } else {
+                    smap_add_format(args, "erspan_hwid", "0x%x",
+                                    tnl_cfg.erspan_hwid);
+                }
+            }
+        }
     }
 
     return 0;
diff --git a/lib/netdev.h b/lib/netdev.h
index 0c74dfebd..71ffdab63 100644
--- a/lib/netdev.h
+++ b/lib/netdev.h
@@ -134,6 +134,11 @@ struct netdev_tunnel_config {
     uint8_t erspan_ver;
     uint8_t erspan_dir;
     uint8_t erspan_hwid;
+
+    bool erspan_ver_flow;
+    bool erspan_idx_flow;
+    bool erspan_dir_flow;
+    bool erspan_hwid_flow;
 };
 
 void netdev_run(void);