mptcp: netlink: issue MP_PRIO signals from userspace PMs

This change updates MPTCP_PM_CMD_SET_FLAGS to allow userspace PMs
to issue MP_PRIO signals over a specific subflow selected by
the connection token, local and remote address+port.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/286
Fixes: 702c2f646d42 ("mptcp: netlink: allow userspace-driven subflow establishment")
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/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index ca86c88..2da251d 100644 (file)
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -717,9 +717,10 @@ void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
        }
 }
 
-static int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
-                                       struct mptcp_addr_info *addr,
-                                       u8 bkup)
+int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
+                                struct mptcp_addr_info *addr,
+                                struct mptcp_addr_info *rem,
+                                u8 bkup)
 {
        struct mptcp_subflow_context *subflow;
 
@@ -727,13 +728,19 @@ static int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
 
        mptcp_for_each_subflow(msk, subflow) {
                struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
-               struct mptcp_addr_info local;
+               struct mptcp_addr_info local, remote;
                bool slow;
 
                local_address((struct sock_common *)ssk, &local);
                if (!mptcp_addresses_equal(&local, addr, addr->port))
                        continue;
 
+               if (rem && rem->family != AF_UNSPEC) {
+                       remote_address((struct sock_common *)ssk, &remote);
+                       if (!mptcp_addresses_equal(&remote, rem, rem->port))
+                               continue;
+               }
+
                slow = lock_sock_fast(ssk);
                if (subflow->backup != bkup)
                        msk->last_snd = NULL;
@@ -1837,7 +1844,7 @@ static int mptcp_nl_set_flags(struct net *net,
 
                lock_sock(sk);
                if (changed & MPTCP_PM_ADDR_FLAG_BACKUP)
-                       ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, bkup);
+                       ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup);
                if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH)
                        mptcp_pm_nl_fullmesh(msk, addr);
                release_sock(sk);
@@ -1853,6 +1860,9 @@ next:
 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
 {
        struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }, *entry;
+       struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, };
+       struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
+       struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
        struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
        struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
        u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP |
@@ -1865,6 +1875,12 @@ static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
        if (ret < 0)
                return ret;
 
+       if (attr_rem) {
+               ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote);
+               if (ret < 0)
+                       return ret;
+       }
+
        if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
                bkup = 1;
        if (addr.addr.family == AF_UNSPEC) {
@@ -1873,6 +1889,10 @@ static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
                        return -EOPNOTSUPP;
        }
 
+       if (token)
+               return mptcp_userspace_pm_set_flags(sock_net(skb->sk),
+                                                   token, &addr, &remote, bkup);
+
        spin_lock_bh(&pernet->lock);
        entry = __lookup_addr(pernet, &addr.addr, lookup_by_id);
        if (!entry) {

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index 26212be..51e2f06 100644 (file)
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -420,3 +420,33 @@ destroy_err:
        sock_put((struct sock *)msk);
        return err;
 }
+
+int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token,
+                                struct mptcp_pm_addr_entry *loc,
+                                struct mptcp_pm_addr_entry *rem, u8 bkup)
+{
+       struct mptcp_sock *msk;
+       int ret = -EINVAL;
+       u32 token_val;
+
+       token_val = nla_get_u32(token);
+
+       msk = mptcp_token_get_sock(net, token_val);
+       if (!msk)
+               return ret;
+
+       if (!mptcp_pm_is_userspace(msk))
+               goto set_flags_err;
+
+       if (loc->addr.family == AF_UNSPEC ||
+           rem->addr.family == AF_UNSPEC)
+               goto set_flags_err;
+
+       lock_sock((struct sock *)msk);
+       ret = mptcp_pm_nl_mp_prio_send_ack(msk, &loc->addr, &rem->addr, bkup);
+       release_sock((struct sock *)msk);
+
+set_flags_err:
+       sock_put((struct sock *)msk);
+       return ret;
+}

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 033c995..480c532 100644 (file)
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -772,6 +772,10 @@ void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
                               const struct mptcp_rm_list *rm_list);
 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup);
 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq);
+int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
+                                struct mptcp_addr_info *addr,
+                                struct mptcp_addr_info *rem,
+                                u8 bkup);
 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
                              const struct mptcp_pm_addr_entry *entry);
 void mptcp_pm_free_anno_list(struct mptcp_sock *msk);
@@ -788,7 +792,9 @@ int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
                                                   unsigned int id,
                                                   u8 *flags, int *ifindex);
-
+int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token,
+                                struct mptcp_pm_addr_entry *loc,
+                                struct mptcp_pm_addr_entry *rem, u8 bkup);
 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
                           const struct mptcp_addr_info *addr,
                           bool echo);