1 /* 2 * udp_diag.c Module for monitoring UDP transport protocols sockets. 3 * 4 * Authors: Pavel Emelyanov, <xemul@parallels.com> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 13 #include <linux/module.h> 14 #include <linux/inet_diag.h> 15 #include <linux/udp.h> 16 #include <net/udp.h> 17 #include <net/udplite.h> 18 #include <linux/sock_diag.h> 19 20 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, 21 struct netlink_callback *cb, 22 const struct inet_diag_req_v2 *req, 23 struct nlattr *bc, bool net_admin) 24 { 25 if (!inet_diag_bc_sk(bc, sk)) 26 return 0; 27 28 return inet_sk_diag_fill(sk, NULL, skb, req, 29 sk_user_ns(NETLINK_CB(cb->skb).sk), 30 NETLINK_CB(cb->skb).portid, 31 cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin); 32 } 33 34 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb, 35 const struct nlmsghdr *nlh, 36 const struct inet_diag_req_v2 *req) 37 { 38 int err = -EINVAL; 39 struct sock *sk = NULL; 40 struct sk_buff *rep; 41 struct net *net = sock_net(in_skb->sk); 42 43 rcu_read_lock(); 44 if (req->sdiag_family == AF_INET) 45 sk = __udp4_lib_lookup(net, 46 req->id.idiag_src[0], req->id.idiag_sport, 47 req->id.idiag_dst[0], req->id.idiag_dport, 48 req->id.idiag_if, tbl, NULL); 49 #if IS_ENABLED(CONFIG_IPV6) 50 else if (req->sdiag_family == AF_INET6) 51 sk = __udp6_lib_lookup(net, 52 (struct in6_addr *)req->id.idiag_src, 53 req->id.idiag_sport, 54 (struct in6_addr *)req->id.idiag_dst, 55 req->id.idiag_dport, 56 req->id.idiag_if, tbl, NULL); 57 #endif 58 if (sk && !atomic_inc_not_zero(&sk->sk_refcnt)) 59 sk = NULL; 60 rcu_read_unlock(); 61 err = -ENOENT; 62 if (!sk) 63 goto out_nosk; 64 65 err = sock_diag_check_cookie(sk, req->id.idiag_cookie); 66 if (err) 67 goto out; 68 69 err = -ENOMEM; 70 rep = nlmsg_new(sizeof(struct inet_diag_msg) + 71 sizeof(struct inet_diag_meminfo) + 64, 72 GFP_KERNEL); 73 if (!rep) 74 goto out; 75 76 err = inet_sk_diag_fill(sk, NULL, rep, req, 77 sk_user_ns(NETLINK_CB(in_skb).sk), 78 NETLINK_CB(in_skb).portid, 79 nlh->nlmsg_seq, 0, nlh, 80 netlink_net_capable(in_skb, CAP_NET_ADMIN)); 81 if (err < 0) { 82 WARN_ON(err == -EMSGSIZE); 83 kfree_skb(rep); 84 goto out; 85 } 86 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 87 MSG_DONTWAIT); 88 if (err > 0) 89 err = 0; 90 out: 91 if (sk) 92 sock_put(sk); 93 out_nosk: 94 return err; 95 } 96 97 static void udp_dump(struct udp_table *table, struct sk_buff *skb, 98 struct netlink_callback *cb, 99 const struct inet_diag_req_v2 *r, struct nlattr *bc) 100 { 101 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); 102 struct net *net = sock_net(skb->sk); 103 int num, s_num, slot, s_slot; 104 105 s_slot = cb->args[0]; 106 num = s_num = cb->args[1]; 107 108 for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) { 109 struct udp_hslot *hslot = &table->hash[slot]; 110 struct sock *sk; 111 112 num = 0; 113 114 if (hlist_empty(&hslot->head)) 115 continue; 116 117 spin_lock_bh(&hslot->lock); 118 sk_for_each(sk, &hslot->head) { 119 struct inet_sock *inet = inet_sk(sk); 120 121 if (!net_eq(sock_net(sk), net)) 122 continue; 123 if (num < s_num) 124 goto next; 125 if (!(r->idiag_states & (1 << sk->sk_state))) 126 goto next; 127 if (r->sdiag_family != AF_UNSPEC && 128 sk->sk_family != r->sdiag_family) 129 goto next; 130 if (r->id.idiag_sport != inet->inet_sport && 131 r->id.idiag_sport) 132 goto next; 133 if (r->id.idiag_dport != inet->inet_dport && 134 r->id.idiag_dport) 135 goto next; 136 137 if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) { 138 spin_unlock_bh(&hslot->lock); 139 goto done; 140 } 141 next: 142 num++; 143 } 144 spin_unlock_bh(&hslot->lock); 145 } 146 done: 147 cb->args[0] = slot; 148 cb->args[1] = num; 149 } 150 151 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 152 const struct inet_diag_req_v2 *r, struct nlattr *bc) 153 { 154 udp_dump(&udp_table, skb, cb, r, bc); 155 } 156 157 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, 158 const struct inet_diag_req_v2 *req) 159 { 160 return udp_dump_one(&udp_table, in_skb, nlh, req); 161 } 162 163 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 164 void *info) 165 { 166 r->idiag_rqueue = sk_rmem_alloc_get(sk); 167 r->idiag_wqueue = sk_wmem_alloc_get(sk); 168 } 169 170 #ifdef CONFIG_INET_DIAG_DESTROY 171 static int __udp_diag_destroy(struct sk_buff *in_skb, 172 const struct inet_diag_req_v2 *req, 173 struct udp_table *tbl) 174 { 175 struct net *net = sock_net(in_skb->sk); 176 struct sock *sk; 177 int err; 178 179 rcu_read_lock(); 180 181 if (req->sdiag_family == AF_INET) 182 sk = __udp4_lib_lookup(net, 183 req->id.idiag_dst[0], req->id.idiag_dport, 184 req->id.idiag_src[0], req->id.idiag_sport, 185 req->id.idiag_if, tbl, NULL); 186 #if IS_ENABLED(CONFIG_IPV6) 187 else if (req->sdiag_family == AF_INET6) { 188 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) && 189 ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src)) 190 sk = __udp4_lib_lookup(net, 191 req->id.idiag_dst[3], req->id.idiag_dport, 192 req->id.idiag_src[3], req->id.idiag_sport, 193 req->id.idiag_if, tbl, NULL); 194 195 else 196 sk = __udp6_lib_lookup(net, 197 (struct in6_addr *)req->id.idiag_dst, 198 req->id.idiag_dport, 199 (struct in6_addr *)req->id.idiag_src, 200 req->id.idiag_sport, 201 req->id.idiag_if, tbl, NULL); 202 } 203 #endif 204 else { 205 rcu_read_unlock(); 206 return -EINVAL; 207 } 208 209 if (sk && !atomic_inc_not_zero(&sk->sk_refcnt)) 210 sk = NULL; 211 212 rcu_read_unlock(); 213 214 if (!sk) 215 return -ENOENT; 216 217 if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) { 218 sock_put(sk); 219 return -ENOENT; 220 } 221 222 err = sock_diag_destroy(sk, ECONNABORTED); 223 224 sock_put(sk); 225 226 return err; 227 } 228 229 static int udp_diag_destroy(struct sk_buff *in_skb, 230 const struct inet_diag_req_v2 *req) 231 { 232 return __udp_diag_destroy(in_skb, req, &udp_table); 233 } 234 235 static int udplite_diag_destroy(struct sk_buff *in_skb, 236 const struct inet_diag_req_v2 *req) 237 { 238 return __udp_diag_destroy(in_skb, req, &udplite_table); 239 } 240 241 #endif 242 243 static const struct inet_diag_handler udp_diag_handler = { 244 .dump = udp_diag_dump, 245 .dump_one = udp_diag_dump_one, 246 .idiag_get_info = udp_diag_get_info, 247 .idiag_type = IPPROTO_UDP, 248 .idiag_info_size = 0, 249 #ifdef CONFIG_INET_DIAG_DESTROY 250 .destroy = udp_diag_destroy, 251 #endif 252 }; 253 254 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 255 const struct inet_diag_req_v2 *r, 256 struct nlattr *bc) 257 { 258 udp_dump(&udplite_table, skb, cb, r, bc); 259 } 260 261 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, 262 const struct inet_diag_req_v2 *req) 263 { 264 return udp_dump_one(&udplite_table, in_skb, nlh, req); 265 } 266 267 static const struct inet_diag_handler udplite_diag_handler = { 268 .dump = udplite_diag_dump, 269 .dump_one = udplite_diag_dump_one, 270 .idiag_get_info = udp_diag_get_info, 271 .idiag_type = IPPROTO_UDPLITE, 272 .idiag_info_size = 0, 273 #ifdef CONFIG_INET_DIAG_DESTROY 274 .destroy = udplite_diag_destroy, 275 #endif 276 }; 277 278 static int __init udp_diag_init(void) 279 { 280 int err; 281 282 err = inet_diag_register(&udp_diag_handler); 283 if (err) 284 goto out; 285 err = inet_diag_register(&udplite_diag_handler); 286 if (err) 287 goto out_lite; 288 out: 289 return err; 290 out_lite: 291 inet_diag_unregister(&udp_diag_handler); 292 goto out; 293 } 294 295 static void __exit udp_diag_exit(void) 296 { 297 inet_diag_unregister(&udplite_diag_handler); 298 inet_diag_unregister(&udp_diag_handler); 299 } 300 301 module_init(udp_diag_init); 302 module_exit(udp_diag_exit); 303 MODULE_LICENSE("GPL"); 304 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); 305 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */); 306