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 stale_loss_cnt; 31 u8 mptcp_enabled; 32 u8 checksum_enabled; 33 u8 allow_join_initial_addr_port; 34 u8 pm_type; 35 }; 36 37 static struct mptcp_pernet *mptcp_get_pernet(const struct net *net) 38 { 39 return net_generic(net, mptcp_pernet_id); 40 } 41 42 int mptcp_is_enabled(const struct net *net) 43 { 44 return mptcp_get_pernet(net)->mptcp_enabled; 45 } 46 47 unsigned int mptcp_get_add_addr_timeout(const struct net *net) 48 { 49 return mptcp_get_pernet(net)->add_addr_timeout; 50 } 51 52 int mptcp_is_checksum_enabled(const struct net *net) 53 { 54 return mptcp_get_pernet(net)->checksum_enabled; 55 } 56 57 int mptcp_allow_join_id0(const struct net *net) 58 { 59 return mptcp_get_pernet(net)->allow_join_initial_addr_port; 60 } 61 62 unsigned int mptcp_stale_loss_cnt(const struct net *net) 63 { 64 return mptcp_get_pernet(net)->stale_loss_cnt; 65 } 66 67 int mptcp_get_pm_type(const struct net *net) 68 { 69 return mptcp_get_pernet(net)->pm_type; 70 } 71 72 static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet) 73 { 74 pernet->mptcp_enabled = 1; 75 pernet->add_addr_timeout = TCP_RTO_MAX; 76 pernet->checksum_enabled = 0; 77 pernet->allow_join_initial_addr_port = 1; 78 pernet->stale_loss_cnt = 4; 79 pernet->pm_type = MPTCP_PM_TYPE_KERNEL; 80 } 81 82 #ifdef CONFIG_SYSCTL 83 static struct ctl_table mptcp_sysctl_table[] = { 84 { 85 .procname = "enabled", 86 .maxlen = sizeof(u8), 87 .mode = 0644, 88 /* users with CAP_NET_ADMIN or root (not and) can change this 89 * value, same as other sysctl or the 'net' tree. 90 */ 91 .proc_handler = proc_dou8vec_minmax, 92 .extra1 = SYSCTL_ZERO, 93 .extra2 = SYSCTL_ONE 94 }, 95 { 96 .procname = "add_addr_timeout", 97 .maxlen = sizeof(unsigned int), 98 .mode = 0644, 99 .proc_handler = proc_dointvec_jiffies, 100 }, 101 { 102 .procname = "checksum_enabled", 103 .maxlen = sizeof(u8), 104 .mode = 0644, 105 .proc_handler = proc_dou8vec_minmax, 106 .extra1 = SYSCTL_ZERO, 107 .extra2 = SYSCTL_ONE 108 }, 109 { 110 .procname = "allow_join_initial_addr_port", 111 .maxlen = sizeof(u8), 112 .mode = 0644, 113 .proc_handler = proc_dou8vec_minmax, 114 .extra1 = SYSCTL_ZERO, 115 .extra2 = SYSCTL_ONE 116 }, 117 { 118 .procname = "stale_loss_cnt", 119 .maxlen = sizeof(unsigned int), 120 .mode = 0644, 121 .proc_handler = proc_douintvec_minmax, 122 }, 123 { 124 .procname = "pm_type", 125 .maxlen = sizeof(u8), 126 .mode = 0644, 127 .proc_handler = proc_dou8vec_minmax, 128 .extra1 = SYSCTL_ZERO, 129 .extra2 = &mptcp_pm_type_max 130 }, 131 {} 132 }; 133 134 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 135 { 136 struct ctl_table_header *hdr; 137 struct ctl_table *table; 138 139 table = mptcp_sysctl_table; 140 if (!net_eq(net, &init_net)) { 141 table = kmemdup(table, sizeof(mptcp_sysctl_table), GFP_KERNEL); 142 if (!table) 143 goto err_alloc; 144 } 145 146 table[0].data = &pernet->mptcp_enabled; 147 table[1].data = &pernet->add_addr_timeout; 148 table[2].data = &pernet->checksum_enabled; 149 table[3].data = &pernet->allow_join_initial_addr_port; 150 table[4].data = &pernet->stale_loss_cnt; 151 table[5].data = &pernet->pm_type; 152 153 hdr = register_net_sysctl(net, MPTCP_SYSCTL_PATH, table); 154 if (!hdr) 155 goto err_reg; 156 157 pernet->ctl_table_hdr = hdr; 158 159 return 0; 160 161 err_reg: 162 if (!net_eq(net, &init_net)) 163 kfree(table); 164 err_alloc: 165 return -ENOMEM; 166 } 167 168 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) 169 { 170 struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg; 171 172 unregister_net_sysctl_table(pernet->ctl_table_hdr); 173 174 kfree(table); 175 } 176 177 #else 178 179 static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) 180 { 181 return 0; 182 } 183 184 static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {} 185 186 #endif /* CONFIG_SYSCTL */ 187 188 static int __net_init mptcp_net_init(struct net *net) 189 { 190 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 191 192 mptcp_pernet_set_defaults(pernet); 193 194 return mptcp_pernet_new_table(net, pernet); 195 } 196 197 /* Note: the callback will only be called per extra netns */ 198 static void __net_exit mptcp_net_exit(struct net *net) 199 { 200 struct mptcp_pernet *pernet = mptcp_get_pernet(net); 201 202 mptcp_pernet_del_table(pernet); 203 } 204 205 static struct pernet_operations mptcp_pernet_ops = { 206 .init = mptcp_net_init, 207 .exit = mptcp_net_exit, 208 .id = &mptcp_pernet_id, 209 .size = sizeof(struct mptcp_pernet), 210 }; 211 212 void __init mptcp_init(void) 213 { 214 mptcp_join_cookie_init(); 215 mptcp_proto_init(); 216 217 if (register_pernet_subsys(&mptcp_pernet_ops) < 0) 218 panic("Failed to register MPTCP pernet subsystem.\n"); 219 } 220 221 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 222 int __init mptcpv6_init(void) 223 { 224 int err; 225 226 err = mptcp_proto_v6_init(); 227 228 return err; 229 } 230 #endif 231