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 unsigned int add_addr_timeout; 25 unsigned int stale_loss_cnt; 26 u8 mptcp_enabled; 27 u8 checksum_enabled; 28 u8 allow_join_initial_addr_port; 29 }; 30 31 static struct mptcp_pernet *mptcp_get_pernet(const struct net *net) 32 { 33 return net_generic(net, mptcp_pernet_id); 34 } 35 36 int mptcp_is_enabled(const struct net *net) 37 { 38 return mptcp_get_pernet(net)->mptcp_enabled; 39 } 40 41 unsigned int mptcp_get_add_addr_timeout(const struct net *net) 42 { 43 return mptcp_get_pernet(net)->add_addr_timeout; 44 } 45 46 int mptcp_is_checksum_enabled(const struct net *net) 47 { 48 return mptcp_get_pernet(net)->checksum_enabled; 49 } 50 51 int mptcp_allow_join_id0(const struct net *net) 52 { 53 return mptcp_get_pernet(net)->allow_join_initial_addr_port; 54 } 55 56 unsigned int mptcp_stale_loss_cnt(const struct net *net) 57 { 58 return mptcp_get_pernet(net)->stale_loss_cnt; 59 } 60 61 static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet) 62 { 63 pernet->mptcp_enabled = 1; 64 pernet->add_addr_timeout = TCP_RTO_MAX; 65 pernet->checksum_enabled = 0; 66 pernet->allow_join_initial_addr_port = 1; 67 pernet->stale_loss_cnt = 4; 68 } 69 70 #ifdef CONFIG_SYSCTL 71 static struct ctl_table mptcp_sysctl_table[] = { 72 { 73 .procname = "enabled", 74 .maxlen = sizeof(u8), 75 .mode = 0644, 76 /* users with CAP_NET_ADMIN or root (not and) can change this 77 * value, same as other sysctl or the 'net' tree. 78 */ 79 .proc_handler = proc_dou8vec_minmax, 80 .extra1 = SYSCTL_ZERO, 81 .extra2 = SYSCTL_ONE 82 }, 83 { 84 .procname = "add_addr_timeout", 85 .maxlen = sizeof(unsigned int), 86 .mode = 0644, 87 .proc_handler = proc_dointvec_jiffies, 88 }, 89 { 90 .procname = "checksum_enabled", 91 .maxlen = sizeof(u8), 92 .mode = 0644, 93 .proc_handler = proc_dou8vec_minmax, 94 .extra1 = SYSCTL_ZERO, 95 .extra2 = SYSCTL_ONE 96 }, 97 { 98 .procname = "allow_join_initial_addr_port", 99 .maxlen = sizeof(u8), 100 .mode = 0644, 101 .proc_handler = proc_dou8vec_minmax, 102 .extra1 = SYSCTL_ZERO, 103 .extra2 = SYSCTL_ONE 104 }, 105 { 106 .procname = "stale_loss_cnt", 107 .maxlen = sizeof(unsigned int), 108 .mode = 0644, 109 .proc_handler = proc_douintvec_minmax, 110 }, 111 {} 112 }; 113 114 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 115 { 116 struct ctl_table_header *hdr; 117 struct ctl_table *table; 118 119 table = mptcp_sysctl_table; 120 if (!net_eq(net, &init_net)) { 121 table = kmemdup(table, sizeof(mptcp_sysctl_table), GFP_KERNEL); 122 if (!table) 123 goto err_alloc; 124 } 125 126 table[0].data = &pernet->mptcp_enabled; 127 table[1].data = &pernet->add_addr_timeout; 128 table[2].data = &pernet->checksum_enabled; 129 table[3].data = &pernet->allow_join_initial_addr_port; 130 table[4].data = &pernet->stale_loss_cnt; 131 132 hdr = register_net_sysctl(net, MPTCP_SYSCTL_PATH, table); 133 if (!hdr) 134 goto err_reg; 135 136 pernet->ctl_table_hdr = hdr; 137 138 return 0; 139 140 err_reg: 141 if (!net_eq(net, &init_net)) 142 kfree(table); 143 err_alloc: 144 return -ENOMEM; 145 } 146 147 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) 148 { 149 struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg; 150 151 unregister_net_sysctl_table(pernet->ctl_table_hdr); 152 153 kfree(table); 154 } 155 156 #else 157 158 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 159 { 160 return 0; 161 } 162 163 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {} 164 165 #endif /* CONFIG_SYSCTL */ 166 167 static int __net_init mptcp_net_init(struct net *net) 168 { 169 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 170 171 mptcp_pernet_set_defaults(pernet); 172 173 return mptcp_pernet_new_table(net, pernet); 174 } 175 176 /* Note: the callback will only be called per extra netns */ 177 static void __net_exit mptcp_net_exit(struct net *net) 178 { 179 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 180 181 mptcp_pernet_del_table(pernet); 182 } 183 184 static struct pernet_operations mptcp_pernet_ops = { 185 .init = mptcp_net_init, 186 .exit = mptcp_net_exit, 187 .id = &mptcp_pernet_id, 188 .size = sizeof(struct mptcp_pernet), 189 }; 190 191 void __init mptcp_init(void) 192 { 193 mptcp_join_cookie_init(); 194 mptcp_proto_init(); 195 196 if (register_pernet_subsys(&mptcp_pernet_ops) < 0) 197 panic("Failed to register MPTCP pernet subsystem.\n"); 198 } 199 200 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 201 int __init mptcpv6_init(void) 202 { 203 int err; 204 205 err = mptcp_proto_v6_init(); 206 207 return err; 208 } 209 #endif 210