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 bool net_admin) 20 { 21 if (!inet_diag_bc_sk(cb->data, 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 = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid); 81 82 out: 83 if (sk) 84 sock_put(sk); 85 out_nosk: 86 return err; 87 } 88 89 static void udp_dump(struct udp_table *table, struct sk_buff *skb, 90 struct netlink_callback *cb, 91 const struct inet_diag_req_v2 *r) 92 { 93 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); 94 struct net *net = sock_net(skb->sk); 95 int num, s_num, slot, s_slot; 96 97 s_slot = cb->args[0]; 98 num = s_num = cb->args[1]; 99 100 for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) { 101 struct udp_hslot *hslot = &table->hash[slot]; 102 struct sock *sk; 103 104 num = 0; 105 106 if (hlist_empty(&hslot->head)) 107 continue; 108 109 spin_lock_bh(&hslot->lock); 110 sk_for_each(sk, &hslot->head) { 111 struct inet_sock *inet = inet_sk(sk); 112 113 if (!net_eq(sock_net(sk), net)) 114 continue; 115 if (num < s_num) 116 goto next; 117 if (!(r->idiag_states & (1 << sk->sk_state))) 118 goto next; 119 if (r->sdiag_family != AF_UNSPEC && 120 sk->sk_family != r->sdiag_family) 121 goto next; 122 if (r->id.idiag_sport != inet->inet_sport && 123 r->id.idiag_sport) 124 goto next; 125 if (r->id.idiag_dport != inet->inet_dport && 126 r->id.idiag_dport) 127 goto next; 128 129 if (sk_diag_dump(sk, skb, cb, r, net_admin) < 0) { 130 spin_unlock_bh(&hslot->lock); 131 goto done; 132 } 133 next: 134 num++; 135 } 136 spin_unlock_bh(&hslot->lock); 137 } 138 done: 139 cb->args[0] = slot; 140 cb->args[1] = num; 141 } 142 143 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 144 const struct inet_diag_req_v2 *r) 145 { 146 udp_dump(sock_net(cb->skb->sk)->ipv4.udp_table, skb, cb, r); 147 } 148 149 static int udp_diag_dump_one(struct netlink_callback *cb, 150 const struct inet_diag_req_v2 *req) 151 { 152 return udp_dump_one(sock_net(cb->skb->sk)->ipv4.udp_table, cb, req); 153 } 154 155 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 156 void *info) 157 { 158 r->idiag_rqueue = udp_rqueue_get(sk); 159 r->idiag_wqueue = sk_wmem_alloc_get(sk); 160 } 161 162 #ifdef CONFIG_INET_DIAG_DESTROY 163 static int __udp_diag_destroy(struct sk_buff *in_skb, 164 const struct inet_diag_req_v2 *req, 165 struct udp_table *tbl) 166 { 167 struct net *net = sock_net(in_skb->sk); 168 struct sock *sk; 169 int err; 170 171 rcu_read_lock(); 172 173 if (req->sdiag_family == AF_INET) 174 sk = __udp4_lib_lookup(net, 175 req->id.idiag_dst[0], req->id.idiag_dport, 176 req->id.idiag_src[0], req->id.idiag_sport, 177 req->id.idiag_if, 0, tbl, NULL); 178 #if IS_ENABLED(CONFIG_IPV6) 179 else if (req->sdiag_family == AF_INET6) { 180 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) && 181 ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src)) 182 sk = __udp4_lib_lookup(net, 183 req->id.idiag_dst[3], req->id.idiag_dport, 184 req->id.idiag_src[3], req->id.idiag_sport, 185 req->id.idiag_if, 0, tbl, NULL); 186 187 else 188 sk = __udp6_lib_lookup(net, 189 (struct in6_addr *)req->id.idiag_dst, 190 req->id.idiag_dport, 191 (struct in6_addr *)req->id.idiag_src, 192 req->id.idiag_sport, 193 req->id.idiag_if, 0, tbl, NULL); 194 } 195 #endif 196 else { 197 rcu_read_unlock(); 198 return -EINVAL; 199 } 200 201 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) 202 sk = NULL; 203 204 rcu_read_unlock(); 205 206 if (!sk) 207 return -ENOENT; 208 209 if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) { 210 sock_put(sk); 211 return -ENOENT; 212 } 213 214 err = sock_diag_destroy(sk, ECONNABORTED); 215 216 sock_put(sk); 217 218 return err; 219 } 220 221 static int udp_diag_destroy(struct sk_buff *in_skb, 222 const struct inet_diag_req_v2 *req) 223 { 224 return __udp_diag_destroy(in_skb, req, sock_net(in_skb->sk)->ipv4.udp_table); 225 } 226 227 static int udplite_diag_destroy(struct sk_buff *in_skb, 228 const struct inet_diag_req_v2 *req) 229 { 230 return __udp_diag_destroy(in_skb, req, &udplite_table); 231 } 232 233 #endif 234 235 static const struct inet_diag_handler udp_diag_handler = { 236 .owner = THIS_MODULE, 237 .dump = udp_diag_dump, 238 .dump_one = udp_diag_dump_one, 239 .idiag_get_info = udp_diag_get_info, 240 .idiag_type = IPPROTO_UDP, 241 .idiag_info_size = 0, 242 #ifdef CONFIG_INET_DIAG_DESTROY 243 .destroy = udp_diag_destroy, 244 #endif 245 }; 246 247 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 248 const struct inet_diag_req_v2 *r) 249 { 250 udp_dump(&udplite_table, skb, cb, r); 251 } 252 253 static int udplite_diag_dump_one(struct netlink_callback *cb, 254 const struct inet_diag_req_v2 *req) 255 { 256 return udp_dump_one(&udplite_table, cb, req); 257 } 258 259 static const struct inet_diag_handler udplite_diag_handler = { 260 .owner = THIS_MODULE, 261 .dump = udplite_diag_dump, 262 .dump_one = udplite_diag_dump_one, 263 .idiag_get_info = udp_diag_get_info, 264 .idiag_type = IPPROTO_UDPLITE, 265 .idiag_info_size = 0, 266 #ifdef CONFIG_INET_DIAG_DESTROY 267 .destroy = udplite_diag_destroy, 268 #endif 269 }; 270 271 static int __init udp_diag_init(void) 272 { 273 int err; 274 275 err = inet_diag_register(&udp_diag_handler); 276 if (err) 277 goto out; 278 err = inet_diag_register(&udplite_diag_handler); 279 if (err) 280 goto out_lite; 281 out: 282 return err; 283 out_lite: 284 inet_diag_unregister(&udp_diag_handler); 285 goto out; 286 } 287 288 static void __exit udp_diag_exit(void) 289 { 290 inet_diag_unregister(&udplite_diag_handler); 291 inet_diag_unregister(&udp_diag_handler); 292 } 293 294 module_init(udp_diag_init); 295 module_exit(udp_diag_exit); 296 MODULE_LICENSE("GPL"); 297 MODULE_DESCRIPTION("UDP socket monitoring via SOCK_DIAG"); 298 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); 299 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */); 300