From 9b9ede93a559acef05dbd780b889f4a9feb1bfd4 Mon Sep 17 00:00:00 2001 From: Matthieu Baerts Date: Thu, 21 Jan 2021 06:49:13 +0000 Subject: [PATCH] mptcp: pm nl: support IPv4 mapped in v6 addresses On one side, we can allow the creation of subflows between v4 mapped in v6 and v4 addresses. For that we look for v4mapped addresses between the local address we want to select and the remote one. On the other side, we also properly deal with received v4mapped addresses, either announced ones or set via Netlink. Fixes: 01cacb00b35c ("mptcp: add netlink-based PM") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/122 Suggested-by: Mat Martineau Reviewed-by: Mat Martineau Co-developed-by: Geliang Tang Signed-off-by: Geliang Tang Signed-off-by: Matthieu Baerts --- net/mptcp/pm_netlink.c | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 9b1f6298bbdba..f0afff6ba015f 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -60,15 +60,20 @@ static bool addresses_equal(const struct mptcp_addr_info *a, { bool addr_equals = false; - if (a->family != b->family) - return false; - - if (a->family == AF_INET) - addr_equals = a->addr.s_addr == b->addr.s_addr; + if (a->family == b->family) { + if (a->family == AF_INET) + addr_equals = a->addr.s_addr == b->addr.s_addr; #if IS_ENABLED(CONFIG_MPTCP_IPV6) - else - addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); + else + addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); + } else if (a->family == AF_INET) { + if (ipv6_addr_v4mapped(&b->addr6)) + addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; + } else if (b->family == AF_INET) { + if (ipv6_addr_v4mapped(&a->addr6)) + addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; #endif + } if (!addr_equals) return false; @@ -137,6 +142,7 @@ select_local_address(const struct pm_nl_pernet *pernet, struct mptcp_sock *msk) { struct mptcp_pm_addr_entry *entry, *ret = NULL; + struct sock *sk = (struct sock *)msk; rcu_read_lock(); __mptcp_flush_join_list(msk); @@ -144,11 +150,20 @@ select_local_address(const struct pm_nl_pernet *pernet, if (!(entry->addr.flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) continue; + if (entry->addr.family != sk->sk_family) { +#if IS_ENABLED(CONFIG_MPTCP_IPV6) + if ((entry->addr.family == AF_INET && + !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || + (sk->sk_family == AF_INET && + !ipv6_addr_v4mapped(&entry->addr.addr6))) +#endif + continue; + } + /* avoid any address already in use by subflows and * pending join */ - if (entry->addr.family == ((struct sock *)msk)->sk_family && - !lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) { + if (!lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) { ret = entry; break; }