mptcp: netlink: Add MPTCP_PM_CMD_REMOVE

This change adds a MPTCP netlink command for issuing a
REMOVE_ADDR signal for an address over the chosen MPTCP
connection from a userspace path manager.

The command requires the following parameters: {token, loc_id}.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h
index ac66c12..11f9fa0 100644 (file)
--- a/include/uapi/linux/mptcp.h
+++ b/include/uapi/linux/mptcp.h
@@ -56,6 +56,7 @@ enum {
        MPTCP_PM_ATTR_RCV_ADD_ADDRS,                    /* u32 */
        MPTCP_PM_ATTR_SUBFLOWS,                         /* u32 */
        MPTCP_PM_ATTR_TOKEN,                            /* u32 */
+       MPTCP_PM_ATTR_LOC_ID,                           /* u8 */
 
        __MPTCP_PM_ATTR_MAX
 };
@@ -95,6 +96,7 @@ enum {
        MPTCP_PM_CMD_GET_LIMITS,
        MPTCP_PM_CMD_SET_FLAGS,
        MPTCP_PM_CMD_ANNOUNCE,
+       MPTCP_PM_CMD_REMOVE,
 
        __MPTCP_PM_CMD_AFTER_LAST
 };

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index dbe5ccd..a26750f 100644 (file)
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -1095,6 +1095,7 @@ static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = {
        [MPTCP_PM_ATTR_RCV_ADD_ADDRS]   = { .type       = NLA_U32,      },
        [MPTCP_PM_ATTR_SUBFLOWS]        = { .type       = NLA_U32,      },
        [MPTCP_PM_ATTR_TOKEN]           = { .type       = NLA_U32,      },
+       [MPTCP_PM_ATTR_LOC_ID]          = { .type       = NLA_U8,       },
 };
 
 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk)
@@ -1504,8 +1505,8 @@ static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info)
        return ret;
 }
 
-static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
-                                              struct list_head *rm_list)
+void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
+                                       struct list_head *rm_list)
 {
        struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 };
        struct mptcp_pm_addr_entry *entry;
@@ -2204,6 +2205,11 @@ static const struct genl_small_ops mptcp_pm_ops[] = {
                .doit   = mptcp_nl_cmd_announce,
                .flags  = GENL_ADMIN_PERM,
        },
+       {
+               .cmd    = MPTCP_PM_CMD_REMOVE,
+               .doit   = mptcp_nl_cmd_remove,
+               .flags  = GENL_ADMIN_PERM,
+       },
 };
 
 static struct genl_family mptcp_genl_family __ro_after_init = {

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index 347184a..3a42c9e 100644 (file)
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -180,3 +180,65 @@ int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info)
        sock_put((struct sock *)msk);
        return err;
 }
+
+int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info)
+{
+       struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
+       struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID];
+       struct mptcp_pm_addr_entry *match = NULL;
+       struct mptcp_pm_addr_entry *entry;
+       struct mptcp_sock *msk;
+       LIST_HEAD(free_list);
+       int err = -EINVAL;
+       u32 token_val;
+       u8 id_val;
+
+       if (!id || !token) {
+               GENL_SET_ERR_MSG(info, "missing required inputs");
+               return err;
+       }
+
+       id_val = nla_get_u8(id);
+       token_val = nla_get_u32(token);
+
+       msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
+       if (!msk) {
+               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+               return err;
+       }
+
+       if (!mptcp_pm_is_userspace(msk)) {
+               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
+               goto remove_err;
+       }
+
+       lock_sock((struct sock *)msk);
+
+       list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
+               if (entry->addr.id == id_val) {
+                       match = entry;
+                       break;
+               }
+       }
+
+       if (!match) {
+               GENL_SET_ERR_MSG(info, "address with specified id not found");
+               release_sock((struct sock *)msk);
+               goto remove_err;
+       }
+
+       list_move(&match->list, &free_list);
+
+       mptcp_pm_remove_addrs_and_subflows(msk, &free_list);
+
+       release_sock((struct sock *)msk);
+
+       list_for_each_entry_safe(match, entry, &free_list, list) {
+               sock_kfree_s((struct sock *)msk, match, sizeof(*match));
+       }
+
+       err = 0;
+ remove_err:
+       sock_put((struct sock *)msk);
+       return err;
+}

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index de645ef..4026aa3 100644 (file)
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -801,10 +801,14 @@ int mptcp_pm_announce_addr(struct mptcp_sock *msk,
                           bool echo);
 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
+void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
+                                       struct list_head *rm_list);
+
 int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
                                             struct mptcp_pm_addr_entry *entry);
 void mptcp_free_local_addr_list(struct mptcp_sock *msk);
 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info);
+int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info);
 
 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
                 const struct sock *ssk, gfp_t gfp);