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