1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * udp_diag.c Module for monitoring UDP transport protocols sockets. 4 * 5 * Authors: Pavel Emelyanov, <xemul@parallels.com> 6 */ 7 8 9 #include <linux/module.h> 10 #include <linux/inet_diag.h> 11 #include <linux/udp.h> 12 #include <net/udp.h> 13 #include <net/udplite.h> 14 #include <linux/sock_diag.h> 15 16 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, 17 struct netlink_callback *cb, 18 const struct inet_diag_req_v2 *req, 19 struct nlattr *bc, bool net_admin) 20 { 21 if (!inet_diag_bc_sk(bc, sk)) 22 return 0; 23 24 return inet_sk_diag_fill(sk, NULL, skb, cb, req, NLM_F_MULTI, 25 net_admin); 26 } 27 28 static int udp_dump_one(struct udp_table *tbl, 29 struct netlink_callback *cb, 30 const struct inet_diag_req_v2 *req) 31 { 32 struct sk_buff *in_skb = cb->skb; 33 int err; 34 struct sock *sk = NULL; 35 struct sk_buff *rep; 36 struct net *net = sock_net(in_skb->sk); 37 38 rcu_read_lock(); 39 if (req->sdiag_family == AF_INET) 40 /* src and dst are swapped for historical reasons */ 41 sk = __udp4_lib_lookup(net, 42 req->id.idiag_src[0], req->id.idiag_sport, 43 req->id.idiag_dst[0], req->id.idiag_dport, 44 req->id.idiag_if, 0, tbl, NULL); 45 #if IS_ENABLED(CONFIG_IPV6) 46 else if (req->sdiag_family == AF_INET6) 47 sk = __udp6_lib_lookup(net, 48 (struct in6_addr *)req->id.idiag_src, 49 req->id.idiag_sport, 50 (struct in6_addr *)req->id.idiag_dst, 51 req->id.idiag_dport, 52 req->id.idiag_if, 0, tbl, NULL); 53 #endif 54 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) 55 sk = NULL; 56 rcu_read_unlock(); 57 err = -ENOENT; 58 if (!sk) 59 goto out_nosk; 60 61 err = sock_diag_check_cookie(sk, req->id.idiag_cookie); 62 if (err) 63 goto out; 64 65 err = -ENOMEM; 66 rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) + 67 inet_diag_msg_attrs_size() + 68 nla_total_size(sizeof(struct inet_diag_meminfo)) + 64, 69 GFP_KERNEL); 70 if (!rep) 71 goto out; 72 73 err = inet_sk_diag_fill(sk, NULL, rep, cb, req, 0, 74 netlink_net_capable(in_skb, CAP_NET_ADMIN)); 75 if (err < 0) { 76 WARN_ON(err == -EMSGSIZE); 77 kfree_skb(rep); 78 goto out; 79 } 80 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 81 MSG_DONTWAIT); 82 if (err > 0) 83 err = 0; 84 out: 85 if (sk) 86 sock_put(sk); 87 out_nosk: 88 return err; 89 } 90 91 static void udp_dump(struct udp_table *table, struct sk_buff *skb, 92 struct netlink_callback *cb, 93 const struct inet_diag_req_v2 *r) 94 { 95 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); 96 struct net *net = sock_net(skb->sk); 97 struct inet_diag_dump_data *cb_data; 98 int num, s_num, slot, s_slot; 99 struct nlattr *bc; 100 101 cb_data = cb->data; 102 bc = cb_data->inet_diag_nla_bc; 103 s_slot = cb->args[0]; 104 num = s_num = cb->args[1]; 105 106 for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) { 107 struct udp_hslot *hslot = &table->hash[slot]; 108 struct sock *sk; 109 110 num = 0; 111 112 if (hlist_empty(&hslot->head)) 113 continue; 114 115 spin_lock_bh(&hslot->lock); 116 sk_for_each(sk, &hslot->head) { 117 struct inet_sock *inet = inet_sk(sk); 118 119 if (!net_eq(sock_net(sk), net)) 120 continue; 121 if (num < s_num) 122 goto next; 123 if (!(r->idiag_states & (1 << sk->sk_state))) 124 goto next; 125 if (r->sdiag_family != AF_UNSPEC && 126 sk->sk_family != r->sdiag_family) 127 goto next; 128 if (r->id.idiag_sport != inet->inet_sport && 129 r->id.idiag_sport) 130 goto next; 131 if (r->id.idiag_dport != inet->inet_dport && 132 r->id.idiag_dport) 133 goto next; 134 135 if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) { 136 spin_unlock_bh(&hslot->lock); 137 goto done; 138 } 139 next: 140 num++; 141 } 142 spin_unlock_bh(&hslot->lock); 143 } 144 done: 145 cb->args[0] = slot; 146 cb->args[1] = num; 147 } 148 149 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 150 const struct inet_diag_req_v2 *r) 151 { 152 udp_dump(&udp_table, skb, cb, r); 153 } 154 155 static int udp_diag_dump_one(struct netlink_callback *cb, 156 const struct inet_diag_req_v2 *req) 157 { 158 return udp_dump_one(&udp_table, cb, req); 159 } 160 161 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 162 void *info) 163 { 164 r->idiag_rqueue = udp_rqueue_get(sk); 165 r->idiag_wqueue = sk_wmem_alloc_get(sk); 166 } 167 168 #ifdef CONFIG_INET_DIAG_DESTROY 169 static int __udp_diag_destroy(struct sk_buff *in_skb, 170 const struct inet_diag_req_v2 *req, 171 struct udp_table *tbl) 172 { 173 struct net *net = sock_net(in_skb->sk); 174 struct sock *sk; 175 int err; 176 177 rcu_read_lock(); 178 179 if (req->sdiag_family == AF_INET) 180 sk = __udp4_lib_lookup(net, 181 req->id.idiag_dst[0], req->id.idiag_dport, 182 req->id.idiag_src[0], req->id.idiag_sport, 183 req->id.idiag_if, 0, tbl, NULL); 184 #if IS_ENABLED(CONFIG_IPV6) 185 else if (req->sdiag_family == AF_INET6) { 186 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) && 187 ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src)) 188 sk = __udp4_lib_lookup(net, 189 req->id.idiag_dst[3], req->id.idiag_dport, 190 req->id.idiag_src[3], req->id.idiag_sport, 191 req->id.idiag_if, 0, tbl, NULL); 192 193 else 194 sk = __udp6_lib_lookup(net, 195 (struct in6_addr *)req->id.idiag_dst, 196 req->id.idiag_dport, 197 (struct in6_addr *)req->id.idiag_src, 198 req->id.idiag_sport, 199 req->id.idiag_if, 0, tbl, NULL); 200 } 201 #endif 202 else { 203 rcu_read_unlock(); 204 return -EINVAL; 205 } 206 207 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) 208 sk = NULL; 209 210 rcu_read_unlock(); 211 212 if (!sk) 213 return -ENOENT; 214 215 if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) { 216 sock_put(sk); 217 return -ENOENT; 218 } 219 220 err = sock_diag_destroy(sk, ECONNABORTED); 221 222 sock_put(sk); 223 224 return err; 225 } 226 227 static int udp_diag_destroy(struct sk_buff *in_skb, 228 const struct inet_diag_req_v2 *req) 229 { 230 return __udp_diag_destroy(in_skb, req, &udp_table); 231 } 232 233 static int udplite_diag_destroy(struct sk_buff *in_skb, 234 const struct inet_diag_req_v2 *req) 235 { 236 return __udp_diag_destroy(in_skb, req, &udplite_table); 237 } 238 239 #endif 240 241 static const struct inet_diag_handler udp_diag_handler = { 242 .dump = udp_diag_dump, 243 .dump_one = udp_diag_dump_one, 244 .idiag_get_info = udp_diag_get_info, 245 .idiag_type = IPPROTO_UDP, 246 .idiag_info_size = 0, 247 #ifdef CONFIG_INET_DIAG_DESTROY 248 .destroy = udp_diag_destroy, 249 #endif 250 }; 251 252 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 253 const struct inet_diag_req_v2 *r) 254 { 255 udp_dump(&udplite_table, skb, cb, r); 256 } 257 258 static int udplite_diag_dump_one(struct netlink_callback *cb, 259 const struct inet_diag_req_v2 *req) 260 { 261 return udp_dump_one(&udplite_table, cb, req); 262 } 263 264 static const struct inet_diag_handler udplite_diag_handler = { 265 .dump = udplite_diag_dump, 266 .dump_one = udplite_diag_dump_one, 267 .idiag_get_info = udp_diag_get_info, 268 .idiag_type = IPPROTO_UDPLITE, 269 .idiag_info_size = 0, 270 #ifdef CONFIG_INET_DIAG_DESTROY 271 .destroy = udplite_diag_destroy, 272 #endif 273 }; 274 275 static int __init udp_diag_init(void) 276 { 277 int err; 278 279 err = inet_diag_register(&udp_diag_handler); 280 if (err) 281 goto out; 282 err = inet_diag_register(&udplite_diag_handler); 283 if (err) 284 goto out_lite; 285 out: 286 return err; 287 out_lite: 288 inet_diag_unregister(&udp_diag_handler); 289 goto out; 290 } 291 292 static void __exit udp_diag_exit(void) 293 { 294 inet_diag_unregister(&udplite_diag_handler); 295 inet_diag_unregister(&udp_diag_handler); 296 } 297 298 module_init(udp_diag_init); 299 module_exit(udp_diag_exit); 300 MODULE_LICENSE("GPL"); 301 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); 302 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */); 303