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(struct sock *sk, struct sk_buff *skb) 17{ 18 struct mptcp_subflow_context *sf; 19 struct nlattr *start; 20 u32 flags = 0; 21 bool slow; 22 int err; 23 24 if (inet_sk_state_load(sk) == TCP_LISTEN) 25 return 0; 26 27 start = nla_nest_start_noflag(skb, INET_ULP_INFO_MPTCP); 28 if (!start) 29 return -EMSGSIZE; 30 31 slow = lock_sock_fast(sk); 32 rcu_read_lock(); 33 sf = rcu_dereference(inet_csk(sk)->icsk_ulp_data); 34 if (!sf) { 35 err = 0; 36 goto nla_failure; 37 } 38 39 if (sf->mp_capable) 40 flags |= MPTCP_SUBFLOW_FLAG_MCAP_REM; 41 if (sf->request_mptcp) 42 flags |= MPTCP_SUBFLOW_FLAG_MCAP_LOC; 43 if (sf->mp_join) 44 flags |= MPTCP_SUBFLOW_FLAG_JOIN_REM; 45 if (sf->request_join) 46 flags |= MPTCP_SUBFLOW_FLAG_JOIN_LOC; 47 if (sf->backup) 48 flags |= MPTCP_SUBFLOW_FLAG_BKUP_REM; 49 if (sf->request_bkup) 50 flags |= MPTCP_SUBFLOW_FLAG_BKUP_LOC; 51 if (sf->fully_established) 52 flags |= MPTCP_SUBFLOW_FLAG_FULLY_ESTABLISHED; 53 if (sf->conn_finished) 54 flags |= MPTCP_SUBFLOW_FLAG_CONNECTED; 55 if (sf->map_valid) 56 flags |= MPTCP_SUBFLOW_FLAG_MAPVALID; 57 58 if (nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_TOKEN_REM, sf->remote_token) || 59 nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_TOKEN_LOC, sf->token) || 60 nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_RELWRITE_SEQ, 61 sf->rel_write_seq) || 62 nla_put_u64_64bit(skb, MPTCP_SUBFLOW_ATTR_MAP_SEQ, sf->map_seq, 63 MPTCP_SUBFLOW_ATTR_PAD) || 64 nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_MAP_SFSEQ, 65 sf->map_subflow_seq) || 66 nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_SSN_OFFSET, sf->ssn_offset) || 67 nla_put_u16(skb, MPTCP_SUBFLOW_ATTR_MAP_DATALEN, 68 sf->map_data_len) || 69 nla_put_u32(skb, MPTCP_SUBFLOW_ATTR_FLAGS, flags) || 70 nla_put_u8(skb, MPTCP_SUBFLOW_ATTR_ID_REM, sf->remote_id) || 71 nla_put_u8(skb, MPTCP_SUBFLOW_ATTR_ID_LOC, subflow_get_local_id(sf))) { 72 err = -EMSGSIZE; 73 goto nla_failure; 74 } 75 76 rcu_read_unlock(); 77 unlock_sock_fast(sk, slow); 78 nla_nest_end(skb, start); 79 return 0; 80 81nla_failure: 82 rcu_read_unlock(); 83 unlock_sock_fast(sk, slow); 84 nla_nest_cancel(skb, start); 85 return err; 86} 87 88static size_t subflow_get_info_size(const struct sock *sk) 89{ 90 size_t size = 0; 91 92 size += nla_total_size(0) + /* INET_ULP_INFO_MPTCP */ 93 nla_total_size(4) + /* MPTCP_SUBFLOW_ATTR_TOKEN_REM */ 94 nla_total_size(4) + /* MPTCP_SUBFLOW_ATTR_TOKEN_LOC */ 95 nla_total_size(4) + /* MPTCP_SUBFLOW_ATTR_RELWRITE_SEQ */ 96 nla_total_size_64bit(8) + /* MPTCP_SUBFLOW_ATTR_MAP_SEQ */ 97 nla_total_size(4) + /* MPTCP_SUBFLOW_ATTR_MAP_SFSEQ */ 98 nla_total_size(2) + /* MPTCP_SUBFLOW_ATTR_SSN_OFFSET */ 99 nla_total_size(2) + /* MPTCP_SUBFLOW_ATTR_MAP_DATALEN */ 100 nla_total_size(4) + /* MPTCP_SUBFLOW_ATTR_FLAGS */ 101 nla_total_size(1) + /* MPTCP_SUBFLOW_ATTR_ID_REM */ 102 nla_total_size(1) + /* MPTCP_SUBFLOW_ATTR_ID_LOC */ 103 0; 104 return size; 105} 106 107void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops) 108{ 109 ops->get_info = subflow_get_info; 110 ops->get_info_size = subflow_get_info_size; 111} 112