LXR linux/net/mptcp/diag.c

   1// SPDX-License-Identifier: GPL-2.0
   2/* MPTCP socket monitoring support
   3 *
   4 * Copyright (c) 2019 Red Hat
   5 *
   6 * Author: Davide Caratti <dcaratti@redhat.com>
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/net.h>
  11#include <linux/inet_diag.h>
  12#include <net/netlink.h>
  13#include <uapi/linux/mptcp.h>
  14#include "protocol.h"
  15
  16static int subflow_get_info(const struct sock *sk, struct sk_buff *skb)
  17{
  18        struct mptcp_subflow_context *sf;
  19        struct nlattr *start;
  20        u32 flags = 0;
  21        int err;
  22
  23        start = nla_nest_start_noflag(skb, INET_ULP_INFO_MPTCP);
  24        if (!start)
  25                return -EMSGSIZE;
  26
  27        rcu_read_lock();
  28        sf = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
  29        if (!sf) {
  30                err = 0;
  31                goto nla_failure;
  32        }
  33
  34        if (sf->mp_capable)
  35                flags |= MPTCP_SUBFLOW_FLAG_MCAP_REM;
  36        if (sf->request_mptcp)
  37                flags |= MPTCP_SUBFLOW_FLAG_MCAP_LOC;
  38        if (sf->mp_join)
  39                flags |= MPTCP_SUBFLOW_FLAG_JOIN_REM;
  40        if (sf->request_join)
  41                flags |= MPTCP_SUBFLOW_FLAG_JOIN_LOC;
  42        if (sf->backup)
  43                flags |= MPTCP_SUBFLOW_FLAG_BKUP_REM;
  44        if (sf->request_bkup)
  45                flags |= MPTCP_SUBFLOW_FLAG_BKUP_LOC;
  46        if (sf->fully_established)
  47                flags |= MPTCP_SUBFLOW_FLAG_FULLY_ESTABLISHED;
  48        if (sf->conn_finished)
  49                flags |= MPTCP_SUBFLOW_FLAG_CONNECTED;
  50        if (sf->map_valid)
  51                flags |= MPTCP_SUBFLOW_FLAG_MAPVALID;
  52
  53        if (nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_TOKEN_REM, sf->remote_token) ||
  54            nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_TOKEN_LOC, sf->token) ||
  55            nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_RELWRITE_SEQ,
  56                        sf->rel_write_seq) ||
  57            nla_put_u64_64bit(skb, MPTCP_SUBFLOW_ATTR_MAP_SEQ, sf->map_seq,
  58                              MPTCP_SUBFLOW_ATTR_PAD) ||
  59            nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_MAP_SFSEQ,
  60                        sf->map_subflow_seq) ||
  61            nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_SSN_OFFSET, sf->ssn_offset) ||
  62            nla_put_u16(skb, MPTCP_SUBFLOW_ATTR_MAP_DATALEN,
  63                        sf->map_data_len) ||
  64            nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_FLAGS, flags) ||
  65            nla_put_u8(skb, MPTCP_SUBFLOW_ATTR_ID_REM, sf->remote_id) ||
  66            nla_put_u8(skb, MPTCP_SUBFLOW_ATTR_ID_LOC, sf->local_id)) {
  67                err = -EMSGSIZE;
  68                goto nla_failure;
  69        }
  70
  71        rcu_read_unlock();
  72        nla_nest_end(skb, start);
  73        return 0;
  74
  75nla_failure:
  76        rcu_read_unlock();
  77        nla_nest_cancel(skb, start);
  78        return err;
  79}
  80
  81static size_t subflow_get_info_size(const struct sock *sk)
  82{
  83        size_t size = 0;
  84
  85        size += nla_total_size(0) +     /* INET_ULP_INFO_MPTCP */
  86                nla_total_size(4) +     /* MPTCP_SUBFLOW_ATTR_TOKEN_REM */
  87                nla_total_size(4) +     /* MPTCP_SUBFLOW_ATTR_TOKEN_LOC */
  88                nla_total_size(4) +     /* MPTCP_SUBFLOW_ATTR_RELWRITE_SEQ */
  89                nla_total_size_64bit(8) +       /* MPTCP_SUBFLOW_ATTR_MAP_SEQ */
  90                nla_total_size(4) +     /* MPTCP_SUBFLOW_ATTR_MAP_SFSEQ */
  91                nla_total_size(2) +     /* MPTCP_SUBFLOW_ATTR_SSN_OFFSET */
  92                nla_total_size(2) +     /* MPTCP_SUBFLOW_ATTR_MAP_DATALEN */
  93                nla_total_size(4) +     /* MPTCP_SUBFLOW_ATTR_FLAGS */
  94                nla_total_size(1) +     /* MPTCP_SUBFLOW_ATTR_ID_REM */
  95                nla_total_size(1) +     /* MPTCP_SUBFLOW_ATTR_ID_LOC */
  96                0;
  97        return size;
  98}
  99
 100void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops)
 101{
 102        ops->get_info = subflow_get_info;
 103        ops->get_info_size = subflow_get_info_size;
 104}
 105