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 = -EINVAL; 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(sizeof(struct inet_diag_msg) + 67 sizeof(struct inet_diag_meminfo) + 64, 68 GFP_KERNEL); 69 if (!rep) 70 goto out; 71 72 err = inet_sk_diag_fill(sk, NULL, rep, cb, req, 0, 73 netlink_net_capable(in_skb, CAP_NET_ADMIN)); 74 if (err < 0) { 75 WARN_ON(err == -EMSGSIZE); 76 kfree_skb(rep); 77 goto out; 78 } 79 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 80 MSG_DONTWAIT); 81 if (err > 0) 82 err = 0; 83 out: 84 if (sk) 85 sock_put(sk); 86 out_nosk: 87 return err; 88 } 89 90 static void udp_dump(struct udp_table *table, struct sk_buff *skb, 91 struct netlink_callback *cb, 92 const struct inet_diag_req_v2 *r) 93 { 94 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); 95 struct net *net = sock_net(skb->sk); 96 struct inet_diag_dump_data *cb_data; 97 int num, s_num, slot, s_slot; 98 struct nlattr *bc; 99 100 cb_data = cb->data; 101 bc = cb_data->inet_diag_nla_bc; 102 s_slot = cb->args[0]; 103 num = s_num = cb->args[1]; 104 105 for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) { 106 struct udp_hslot *hslot = &table->hash[slot]; 107 struct sock *sk; 108 109 num = 0; 110 111 if (hlist_empty(&hslot->head)) 112 continue; 113 114 spin_lock_bh(&hslot->lock); 115 sk_for_each(sk, &hslot->head) { 116 struct inet_sock *inet = inet_sk(sk); 117 118 if (!net_eq(sock_net(sk), net)) 119 continue; 120 if (num < s_num) 121 goto next; 122 if (!(r->idiag_states & (1 << sk->sk_state))) 123 goto next; 124 if (r->sdiag_family != AF_UNSPEC && 125 sk->sk_family != r->sdiag_family) 126 goto next; 127 if (r->id.idiag_sport != inet->inet_sport && 128 r->id.idiag_sport) 129 goto next; 130 if (r->id.idiag_dport != inet->inet_dport && 131 r->id.idiag_dport) 132 goto next; 133 134 if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) { 135 spin_unlock_bh(&hslot->lock); 136 goto done; 137 } 138 next: 139 num++; 140 } 141 spin_unlock_bh(&hslot->lock); 142 } 143 done: 144 cb->args[0] = slot; 145 cb->args[1] = num; 146 } 147 148 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 149 const struct inet_diag_req_v2 *r) 150 { 151 udp_dump(&udp_table, skb, cb, r); 152 } 153 154 static int udp_diag_dump_one(struct netlink_callback *cb, 155 const struct inet_diag_req_v2 *req) 156 { 157 return udp_dump_one(&udp_table, cb, req); 158 } 159 160 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 161 void *info) 162 { 163 r->idiag_rqueue = udp_rqueue_get(sk); 164 r->idiag_wqueue = sk_wmem_alloc_get(sk); 165 } 166 167 #ifdef CONFIG_INET_DIAG_DESTROY 168 static int __udp_diag_destroy(struct sk_buff *in_skb, 169 const struct inet_diag_req_v2 *req, 170 struct udp_table *tbl) 171 { 172 struct net *net = sock_net(in_skb->sk); 173 struct sock *sk; 174 int err; 175 176 rcu_read_lock(); 177 178 if (req->sdiag_family == AF_INET) 179 sk = __udp4_lib_lookup(net, 180 req->id.idiag_dst[0], req->id.idiag_dport, 181 req->id.idiag_src[0], req->id.idiag_sport, 182 req->id.idiag_if, 0, tbl, NULL); 183 #if IS_ENABLED(CONFIG_IPV6) 184 else if (req->sdiag_family == AF_INET6) { 185 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) && 186 ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src)) 187 sk = __udp4_lib_lookup(net, 188 req->id.idiag_dst[3], req->id.idiag_dport, 189 req->id.idiag_src[3], req->id.idiag_sport, 190 req->id.idiag_if, 0, tbl, NULL); 191 192 else 193 sk = __udp6_lib_lookup(net, 194 (struct in6_addr *)req->id.idiag_dst, 195 req->id.idiag_dport, 196 (struct in6_addr *)req->id.idiag_src, 197 req->id.idiag_sport, 198 req->id.idiag_if, 0, tbl, NULL); 199 } 200 #endif 201 else { 202 rcu_read_unlock(); 203 return -EINVAL; 204 } 205 206 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) 207 sk = NULL; 208 209 rcu_read_unlock(); 210 211 if (!sk) 212 return -ENOENT; 213 214 if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) { 215 sock_put(sk); 216 return -ENOENT; 217 } 218 219 err = sock_diag_destroy(sk, ECONNABORTED); 220 221 sock_put(sk); 222 223 return err; 224 } 225 226 static int udp_diag_destroy(struct sk_buff *in_skb, 227 const struct inet_diag_req_v2 *req) 228 { 229 return __udp_diag_destroy(in_skb, req, &udp_table); 230 } 231 232 static int udplite_diag_destroy(struct sk_buff *in_skb, 233 const struct inet_diag_req_v2 *req) 234 { 235 return __udp_diag_destroy(in_skb, req, &udplite_table); 236 } 237 238 #endif 239 240 static const struct inet_diag_handler udp_diag_handler = { 241 .dump = udp_diag_dump, 242 .dump_one = udp_diag_dump_one, 243 .idiag_get_info = udp_diag_get_info, 244 .idiag_type = IPPROTO_UDP, 245 .idiag_info_size = 0, 246 #ifdef CONFIG_INET_DIAG_DESTROY 247 .destroy = udp_diag_destroy, 248 #endif 249 }; 250 251 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 252 const struct inet_diag_req_v2 *r) 253 { 254 udp_dump(&udplite_table, skb, cb, r); 255 } 256 257 static int udplite_diag_dump_one(struct netlink_callback *cb, 258 const struct inet_diag_req_v2 *req) 259 { 260 return udp_dump_one(&udplite_table, cb, req); 261 } 262 263 static const struct inet_diag_handler udplite_diag_handler = { 264 .dump = udplite_diag_dump, 265 .dump_one = udplite_diag_dump_one, 266 .idiag_get_info = udp_diag_get_info, 267 .idiag_type = IPPROTO_UDPLITE, 268 .idiag_info_size = 0, 269 #ifdef CONFIG_INET_DIAG_DESTROY 270 .destroy = udplite_diag_destroy, 271 #endif 272 }; 273 274 static int __init udp_diag_init(void) 275 { 276 int err; 277 278 err = inet_diag_register(&udp_diag_handler); 279 if (err) 280 goto out; 281 err = inet_diag_register(&udplite_diag_handler); 282 if (err) 283 goto out_lite; 284 out: 285 return err; 286 out_lite: 287 inet_diag_unregister(&udp_diag_handler); 288 goto out; 289 } 290 291 static void __exit udp_diag_exit(void) 292 { 293 inet_diag_unregister(&udplite_diag_handler); 294 inet_diag_unregister(&udp_diag_handler); 295 } 296 297 module_init(udp_diag_init); 298 module_exit(udp_diag_exit); 299 MODULE_LICENSE("GPL"); 300 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); 301 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */); 302