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(sizeof(struct inet_diag_msg) + 68 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, req, 74 sk_user_ns(NETLINK_CB(in_skb).sk), 75 NETLINK_CB(in_skb).portid, 76 nlh->nlmsg_seq, 0, nlh, 77 netlink_net_capable(in_skb, CAP_NET_ADMIN)); 78 if (err < 0) { 79 WARN_ON(err == -EMSGSIZE); 80 kfree_skb(rep); 81 goto out; 82 } 83 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 84 MSG_DONTWAIT); 85 if (err > 0) 86 err = 0; 87 out: 88 if (sk) 89 sock_put(sk); 90 out_nosk: 91 return err; 92 } 93 94 static void udp_dump(struct udp_table *table, struct sk_buff *skb, 95 struct netlink_callback *cb, 96 const struct inet_diag_req_v2 *r, struct nlattr *bc) 97 { 98 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); 99 struct net *net = sock_net(skb->sk); 100 int num, s_num, slot, s_slot; 101 102 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, struct nlattr *bc) 150 { 151 udp_dump(&udp_table, skb, cb, r, bc); 152 } 153 154 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, 155 const struct inet_diag_req_v2 *req) 156 { 157 return udp_dump_one(&udp_table, in_skb, nlh, 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 struct nlattr *bc) 254 { 255 udp_dump(&udplite_table, skb, cb, r, bc); 256 } 257 258 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, 259 const struct inet_diag_req_v2 *req) 260 { 261 return udp_dump_one(&udplite_table, in_skb, nlh, 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