From 0f9f696a502e1b01fbb137a08f56f157da9d95eb Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Fri, 8 Jan 2021 16:47:59 -0800 Subject: [PATCH] mptcp: add set_flags command in PM netlink This patch added a new command MPTCP_PM_CMD_SET_FLAGS in PM netlink: In mptcp_nl_cmd_set_flags, parse the input address, get the backup value according to whether the address's FLAG_BACKUP flag is set from the user-space. Then check whether this address had been added in the local address list. If it had been, then call mptcp_nl_addr_backup to deal with this address. In mptcp_nl_addr_backup, traverse all the existing msk sockets to find the relevant sockets, and call mptcp_pm_nl_mp_prio_send_ack to send out a MP_PRIO ACK packet. Finally in mptcp_nl_cmd_set_flags, set or clear the address's FLAG_BACKUP flag. Signed-off-by: Geliang Tang Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski --- include/uapi/linux/mptcp.h | 1 + net/mptcp/pm_netlink.c | 65 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+) diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h index 9762660df741..3674a451a18c 100644 --- a/include/uapi/linux/mptcp.h +++ b/include/uapi/linux/mptcp.h @@ -82,6 +82,7 @@ enum { MPTCP_PM_CMD_FLUSH_ADDRS, MPTCP_PM_CMD_SET_LIMITS, MPTCP_PM_CMD_GET_LIMITS, + MPTCP_PM_CMD_SET_FLAGS, __MPTCP_PM_CMD_AFTER_LAST }; diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index bf0d13c85a68..8f80099f1657 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -1164,6 +1164,66 @@ mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info) return -EMSGSIZE; } +static int mptcp_nl_addr_backup(struct net *net, + struct mptcp_addr_info *addr, + u8 bkup) +{ + long s_slot = 0, s_num = 0; + struct mptcp_sock *msk; + int ret = -EINVAL; + + while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { + struct sock *sk = (struct sock *)msk; + + if (list_empty(&msk->conn_list)) + goto next; + + lock_sock(sk); + spin_lock_bh(&msk->pm.lock); + ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, bkup); + spin_unlock_bh(&msk->pm.lock); + release_sock(sk); + +next: + sock_put(sk); + cond_resched(); + } + + return ret; +} + +static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; + struct pm_nl_pernet *pernet = genl_info_pm_nl(info); + struct mptcp_pm_addr_entry addr, *entry; + struct net *net = sock_net(skb->sk); + u8 bkup = 0; + int ret; + + ret = mptcp_pm_parse_addr(attr, info, true, &addr); + if (ret < 0) + return ret; + + if (addr.addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) + bkup = 1; + + list_for_each_entry(entry, &pernet->local_addr_list, list) { + if (addresses_equal(&entry->addr, &addr.addr, true)) { + ret = mptcp_nl_addr_backup(net, &entry->addr, bkup); + if (ret) + return ret; + + if (bkup) + entry->addr.flags |= MPTCP_PM_ADDR_FLAG_BACKUP; + else + entry->addr.flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP; + } + } + + return 0; +} + static const struct genl_small_ops mptcp_pm_ops[] = { { .cmd = MPTCP_PM_CMD_ADD_ADDR, @@ -1194,6 +1254,11 @@ static const struct genl_small_ops mptcp_pm_ops[] = { .cmd = MPTCP_PM_CMD_GET_LIMITS, .doit = mptcp_nl_cmd_get_limits, }, + { + .cmd = MPTCP_PM_CMD_SET_FLAGS, + .doit = mptcp_nl_cmd_set_flags, + .flags = GENL_ADMIN_PERM, + }, }; static struct genl_family mptcp_genl_family __ro_after_init = {