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 16 static 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 75 nla_failure: 76 rcu_read_unlock(); 77 nla_nest_cancel(skb, start); 78 return err; 79 } 80 81 static 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 } 99 100 void 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