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 20 #ifdef CONFIG_SYSCTL 21 static int mptcp_pm_type_max = __MPTCP_PM_TYPE_MAX; 22 #endif 23 24 struct mptcp_pernet { 25 #ifdef CONFIG_SYSCTL 26 struct ctl_table_header *ctl_table_hdr; 27 #endif 28 29 unsigned int add_addr_timeout; 30 unsigned int close_timeout; 31 unsigned int stale_loss_cnt; 32 u8 mptcp_enabled; 33 u8 checksum_enabled; 34 u8 allow_join_initial_addr_port; 35 u8 pm_type; 36 char scheduler[MPTCP_SCHED_NAME_MAX]; 37 }; 38 39 static struct mptcp_pernet *mptcp_get_pernet(const struct net *net) 40 { 41 return net_generic(net, mptcp_pernet_id); 42 } 43 44 int mptcp_is_enabled(const struct net *net) 45 { 46 return mptcp_get_pernet(net)->mptcp_enabled; 47 } 48 49 unsigned int mptcp_get_add_addr_timeout(const struct net *net) 50 { 51 return mptcp_get_pernet(net)->add_addr_timeout; 52 } 53 54 int mptcp_is_checksum_enabled(const struct net *net) 55 { 56 return mptcp_get_pernet(net)->checksum_enabled; 57 } 58 59 int mptcp_allow_join_id0(const struct net *net) 60 { 61 return mptcp_get_pernet(net)->allow_join_initial_addr_port; 62 } 63 64 unsigned int mptcp_stale_loss_cnt(const struct net *net) 65 { 66 return mptcp_get_pernet(net)->stale_loss_cnt; 67 } 68 69 unsigned int mptcp_close_timeout(const struct sock *sk) 70 { 71 if (sock_flag(sk, SOCK_DEAD)) 72 return TCP_TIMEWAIT_LEN; 73 return mptcp_get_pernet(sock_net(sk))->close_timeout; 74 } 75 76 int mptcp_get_pm_type(const struct net *net) 77 { 78 return mptcp_get_pernet(net)->pm_type; 79 } 80 81 const char *mptcp_get_scheduler(const struct net *net) 82 { 83 return mptcp_get_pernet(net)->scheduler; 84 } 85 86 static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet) 87 { 88 pernet->mptcp_enabled = 1; 89 pernet->add_addr_timeout = TCP_RTO_MAX; 90 pernet->close_timeout = TCP_TIMEWAIT_LEN; 91 pernet->checksum_enabled = 0; 92 pernet->allow_join_initial_addr_port = 1; 93 pernet->stale_loss_cnt = 4; 94 pernet->pm_type = MPTCP_PM_TYPE_KERNEL; 95 strcpy(pernet->scheduler, "default"); 96 } 97 98 #ifdef CONFIG_SYSCTL 99 static int mptcp_set_scheduler(const struct net *net, const char *name) 100 { 101 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 102 struct mptcp_sched_ops *sched; 103 int ret = 0; 104 105 rcu_read_lock(); 106 sched = mptcp_sched_find(name); 107 if (sched) 108 strscpy(pernet->scheduler, name, MPTCP_SCHED_NAME_MAX); 109 else 110 ret = -ENOENT; 111 rcu_read_unlock(); 112 113 return ret; 114 } 115 116 static int proc_scheduler(struct ctl_table *ctl, int write, 117 void *buffer, size_t *lenp, loff_t *ppos) 118 { 119 const struct net *net = current->nsproxy->net_ns; 120 char val[MPTCP_SCHED_NAME_MAX]; 121 struct ctl_table tbl = { 122 .data = val, 123 .maxlen = MPTCP_SCHED_NAME_MAX, 124 }; 125 int ret; 126 127 strscpy(val, mptcp_get_scheduler(net), MPTCP_SCHED_NAME_MAX); 128 129 ret = proc_dostring(&tbl, write, buffer, lenp, ppos); 130 if (write && ret == 0) 131 ret = mptcp_set_scheduler(net, val); 132 133 return ret; 134 } 135 136 static struct ctl_table mptcp_sysctl_table[] = { 137 { 138 .procname = "enabled", 139 .maxlen = sizeof(u8), 140 .mode = 0644, 141 /* users with CAP_NET_ADMIN or root (not and) can change this 142 * value, same as other sysctl or the 'net' tree. 143 */ 144 .proc_handler = proc_dou8vec_minmax, 145 .extra1 = SYSCTL_ZERO, 146 .extra2 = SYSCTL_ONE 147 }, 148 { 149 .procname = "add_addr_timeout", 150 .maxlen = sizeof(unsigned int), 151 .mode = 0644, 152 .proc_handler = proc_dointvec_jiffies, 153 }, 154 { 155 .procname = "checksum_enabled", 156 .maxlen = sizeof(u8), 157 .mode = 0644, 158 .proc_handler = proc_dou8vec_minmax, 159 .extra1 = SYSCTL_ZERO, 160 .extra2 = SYSCTL_ONE 161 }, 162 { 163 .procname = "allow_join_initial_addr_port", 164 .maxlen = sizeof(u8), 165 .mode = 0644, 166 .proc_handler = proc_dou8vec_minmax, 167 .extra1 = SYSCTL_ZERO, 168 .extra2 = SYSCTL_ONE 169 }, 170 { 171 .procname = "stale_loss_cnt", 172 .maxlen = sizeof(unsigned int), 173 .mode = 0644, 174 .proc_handler = proc_douintvec_minmax, 175 }, 176 { 177 .procname = "pm_type", 178 .maxlen = sizeof(u8), 179 .mode = 0644, 180 .proc_handler = proc_dou8vec_minmax, 181 .extra1 = SYSCTL_ZERO, 182 .extra2 = &mptcp_pm_type_max 183 }, 184 { 185 .procname = "scheduler", 186 .maxlen = MPTCP_SCHED_NAME_MAX, 187 .mode = 0644, 188 .proc_handler = proc_scheduler, 189 }, 190 { 191 .procname = "close_timeout", 192 .maxlen = sizeof(unsigned int), 193 .mode = 0644, 194 .proc_handler = proc_dointvec_jiffies, 195 }, 196 {} 197 }; 198 199 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 200 { 201 struct ctl_table_header *hdr; 202 struct ctl_table *table; 203 204 table = mptcp_sysctl_table; 205 if (!net_eq(net, &init_net)) { 206 table = kmemdup(table, sizeof(mptcp_sysctl_table), GFP_KERNEL); 207 if (!table) 208 goto err_alloc; 209 } 210 211 table[0].data = &pernet->mptcp_enabled; 212 table[1].data = &pernet->add_addr_timeout; 213 table[2].data = &pernet->checksum_enabled; 214 table[3].data = &pernet->allow_join_initial_addr_port; 215 table[4].data = &pernet->stale_loss_cnt; 216 table[5].data = &pernet->pm_type; 217 table[6].data = &pernet->scheduler; 218 table[7].data = &pernet->close_timeout; 219 220 hdr = register_net_sysctl_sz(net, MPTCP_SYSCTL_PATH, table, 221 ARRAY_SIZE(mptcp_sysctl_table)); 222 if (!hdr) 223 goto err_reg; 224 225 pernet->ctl_table_hdr = hdr; 226 227 return 0; 228 229 err_reg: 230 if (!net_eq(net, &init_net)) 231 kfree(table); 232 err_alloc: 233 return -ENOMEM; 234 } 235 236 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) 237 { 238 struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg; 239 240 unregister_net_sysctl_table(pernet->ctl_table_hdr); 241 242 kfree(table); 243 } 244 245 #else 246 247 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 248 { 249 return 0; 250 } 251 252 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {} 253 254 #endif /* CONFIG_SYSCTL */ 255 256 static int __net_init mptcp_net_init(struct net *net) 257 { 258 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 259 260 mptcp_pernet_set_defaults(pernet); 261 262 return mptcp_pernet_new_table(net, pernet); 263 } 264 265 /* Note: the callback will only be called per extra netns */ 266 static void __net_exit mptcp_net_exit(struct net *net) 267 { 268 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 269 270 mptcp_pernet_del_table(pernet); 271 } 272 273 static struct pernet_operations mptcp_pernet_ops = { 274 .init = mptcp_net_init, 275 .exit = mptcp_net_exit, 276 .id = &mptcp_pernet_id, 277 .size = sizeof(struct mptcp_pernet), 278 }; 279 280 void __init mptcp_init(void) 281 { 282 mptcp_join_cookie_init(); 283 mptcp_proto_init(); 284 285 if (register_pernet_subsys(&mptcp_pernet_ops) < 0) 286 panic("Failed to register MPTCP pernet subsystem.\n"); 287 } 288 289 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 290 int __init mptcpv6_init(void) 291 { 292 int err; 293 294 err = mptcp_proto_v6_init(); 295 296 return err; 297 } 298 #endif 299