1 // SPDX-License-Identifier: GPL-2.0 2 /* Multipath TCP 3 * 4 * Copyright (c) 2019, Tessares SA. 5 */ 6 7 #ifdef CONFIG_SYSCTL 8 #include <linux/sysctl.h> 9 #endif 10 11 #include <net/net_namespace.h> 12 #include <net/netns/generic.h> 13 14 #include "protocol.h" 15 16 #define MPTCP_SYSCTL_PATH "net/mptcp" 17 18 static int mptcp_pernet_id; 19 struct mptcp_pernet { 20 #ifdef CONFIG_SYSCTL 21 struct ctl_table_header *ctl_table_hdr; 22 #endif 23 24 u8 mptcp_enabled; 25 unsigned int add_addr_timeout; 26 }; 27 28 static struct mptcp_pernet *mptcp_get_pernet(struct net *net) 29 { 30 return net_generic(net, mptcp_pernet_id); 31 } 32 33 int mptcp_is_enabled(struct net *net) 34 { 35 return mptcp_get_pernet(net)->mptcp_enabled; 36 } 37 38 unsigned int mptcp_get_add_addr_timeout(struct net *net) 39 { 40 return mptcp_get_pernet(net)->add_addr_timeout; 41 } 42 43 static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet) 44 { 45 pernet->mptcp_enabled = 1; 46 pernet->add_addr_timeout = TCP_RTO_MAX; 47 } 48 49 #ifdef CONFIG_SYSCTL 50 static struct ctl_table mptcp_sysctl_table[] = { 51 { 52 .procname = "enabled", 53 .maxlen = sizeof(u8), 54 .mode = 0644, 55 /* users with CAP_NET_ADMIN or root (not and) can change this 56 * value, same as other sysctl or the 'net' tree. 57 */ 58 .proc_handler = proc_dou8vec_minmax, 59 .extra1 = SYSCTL_ZERO, 60 .extra2 = SYSCTL_ONE 61 }, 62 { 63 .procname = "add_addr_timeout", 64 .maxlen = sizeof(unsigned int), 65 .mode = 0644, 66 .proc_handler = proc_dointvec_jiffies, 67 }, 68 {} 69 }; 70 71 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 72 { 73 struct ctl_table_header *hdr; 74 struct ctl_table *table; 75 76 table = mptcp_sysctl_table; 77 if (!net_eq(net, &init_net)) { 78 table = kmemdup(table, sizeof(mptcp_sysctl_table), GFP_KERNEL); 79 if (!table) 80 goto err_alloc; 81 } 82 83 table[0].data = &pernet->mptcp_enabled; 84 table[1].data = &pernet->add_addr_timeout; 85 86 hdr = register_net_sysctl(net, MPTCP_SYSCTL_PATH, table); 87 if (!hdr) 88 goto err_reg; 89 90 pernet->ctl_table_hdr = hdr; 91 92 return 0; 93 94 err_reg: 95 if (!net_eq(net, &init_net)) 96 kfree(table); 97 err_alloc: 98 return -ENOMEM; 99 } 100 101 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) 102 { 103 struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg; 104 105 unregister_net_sysctl_table(pernet->ctl_table_hdr); 106 107 kfree(table); 108 } 109 110 #else 111 112 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 113 { 114 return 0; 115 } 116 117 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {} 118 119 #endif /* CONFIG_SYSCTL */ 120 121 static int __net_init mptcp_net_init(struct net *net) 122 { 123 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 124 125 mptcp_pernet_set_defaults(pernet); 126 127 return mptcp_pernet_new_table(net, pernet); 128 } 129 130 /* Note: the callback will only be called per extra netns */ 131 static void __net_exit mptcp_net_exit(struct net *net) 132 { 133 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 134 135 mptcp_pernet_del_table(pernet); 136 } 137 138 static struct pernet_operations mptcp_pernet_ops = { 139 .init = mptcp_net_init, 140 .exit = mptcp_net_exit, 141 .id = &mptcp_pernet_id, 142 .size = sizeof(struct mptcp_pernet), 143 }; 144 145 void __init mptcp_init(void) 146 { 147 mptcp_join_cookie_init(); 148 mptcp_proto_init(); 149 150 if (register_pernet_subsys(&mptcp_pernet_ops) < 0) 151 panic("Failed to register MPTCP pernet subsystem.\n"); 152 } 153 154 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 155 int __init mptcpv6_init(void) 156 { 157 int err; 158 159 err = mptcp_proto_v6_init(); 160 161 return err; 162 } 163 #endif 164