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, req, 25 sk_user_ns(NETLINK_CB(cb->skb).sk), 26 NETLINK_CB(cb->skb).portid, 27 cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin); 28 } 29 30 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb, 31 const struct nlmsghdr *nlh, 32 const struct inet_diag_req_v2 *req) 33 { 34 int err = -EINVAL; 35 struct sock *sk = NULL; 36 struct sk_buff *rep; 37 struct net *net = sock_net(in_skb->sk); 38 39 rcu_read_lock(); 40 if (req->sdiag_family == AF_INET) 41 /* src and dst are swapped for historical reasons */ 42 sk = __udp4_lib_lookup(net, 43 req->id.idiag_src[0], req->id.idiag_sport, 44 req->id.idiag_dst[0], req->id.idiag_dport, 45 req->id.idiag_if, 0, tbl, NULL); 46 #if IS_ENABLED(CONFIG_IPV6) 47 else if (req->sdiag_family == AF_INET6) 48 sk = __udp6_lib_lookup(net, 49 (struct in6_addr *)req->id.idiag_src, 50 req->id.idiag_sport, 51 (struct in6_addr *)req->id.idiag_dst, 52 req->id.idiag_dport, 53 req->id.idiag_if, 0, tbl, NULL); 54 #endif 55 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) 56 sk = NULL; 57 rcu_read_unlock(); 58 err = -ENOENT; 59 if (!sk) 60 goto out_nosk; 61 62 err = sock_diag_check_cookie(sk, req->id.idiag_cookie); 63 if (err) 64 goto out; 65 66 err = -ENOMEM; 67 rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) + 68 inet_diag_msg_attrs_size() + 69 nla_total_size(sizeof(struct inet_diag_meminfo)) + 64, 70 GFP_KERNEL); 71 if (!rep) 72 goto out; 73 74 err = inet_sk_diag_fill(sk, NULL, rep, req, 75 sk_user_ns(NETLINK_CB(in_skb).sk), 76 NETLINK_CB(in_skb).portid, 77 nlh->nlmsg_seq, 0, nlh, 78 netlink_net_capable(in_skb, CAP_NET_ADMIN)); 79 if (err < 0) { 80 WARN_ON(err == -EMSGSIZE); 81 kfree_skb(rep); 82 goto out; 83 } 84 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 85 MSG_DONTWAIT); 86 if (err > 0) 87 err = 0; 88 out: 89 if (sk) 90 sock_put(sk); 91 out_nosk: 92 return err; 93 } 94 95 static void udp_dump(struct udp_table *table, struct sk_buff *skb, 96 struct netlink_callback *cb, 97 const struct inet_diag_req_v2 *r, struct nlattr *bc) 98 { 99 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); 100 struct net *net = sock_net(skb->sk); 101 int num, s_num, slot, s_slot; 102 103 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, struct nlattr *bc) 151 { 152 udp_dump(&udp_table, skb, cb, r, bc); 153 } 154 155 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, 156 const struct inet_diag_req_v2 *req) 157 { 158 return udp_dump_one(&udp_table, in_skb, nlh, 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 struct nlattr *bc) 255 { 256 udp_dump(&udplite_table, skb, cb, r, bc); 257 } 258 259 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, 260 const struct inet_diag_req_v2 *req) 261 { 262 return udp_dump_one(&udplite_table, in_skb, nlh, req); 263 } 264 265 static const struct inet_diag_handler udplite_diag_handler = { 266 .dump = udplite_diag_dump, 267 .dump_one = udplite_diag_dump_one, 268 .idiag_get_info = udp_diag_get_info, 269 .idiag_type = IPPROTO_UDPLITE, 270 .idiag_info_size = 0, 271 #ifdef CONFIG_INET_DIAG_DESTROY 272 .destroy = udplite_diag_destroy, 273 #endif 274 }; 275 276 static int __init udp_diag_init(void) 277 { 278 int err; 279 280 err = inet_diag_register(&udp_diag_handler); 281 if (err) 282 goto out; 283 err = inet_diag_register(&udplite_diag_handler); 284 if (err) 285 goto out_lite; 286 out: 287 return err; 288 out_lite: 289 inet_diag_unregister(&udp_diag_handler); 290 goto out; 291 } 292 293 static void __exit udp_diag_exit(void) 294 { 295 inet_diag_unregister(&udplite_diag_handler); 296 inet_diag_unregister(&udp_diag_handler); 297 } 298 299 module_init(udp_diag_init); 300 module_exit(udp_diag_exit); 301 MODULE_LICENSE("GPL"); 302 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); 303 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */); 304