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) 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); 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 if (err < 0) { 81 WARN_ON(err == -EMSGSIZE); 82 kfree_skb(rep); 83 goto out; 84 } 85 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 86 MSG_DONTWAIT); 87 if (err > 0) 88 err = 0; 89 out: 90 if (sk) 91 sock_put(sk); 92 out_nosk: 93 return err; 94 } 95 96 static void udp_dump(struct udp_table *table, struct sk_buff *skb, 97 struct netlink_callback *cb, 98 const struct inet_diag_req_v2 *r, struct nlattr *bc) 99 { 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) < 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 = sk_rmem_alloc_get(sk); 165 r->idiag_wqueue = sk_wmem_alloc_get(sk); 166 } 167 168 static const struct inet_diag_handler udp_diag_handler = { 169 .dump = udp_diag_dump, 170 .dump_one = udp_diag_dump_one, 171 .idiag_get_info = udp_diag_get_info, 172 .idiag_type = IPPROTO_UDP, 173 .idiag_info_size = 0, 174 }; 175 176 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, 177 const struct inet_diag_req_v2 *r, 178 struct nlattr *bc) 179 { 180 udp_dump(&udplite_table, skb, cb, r, bc); 181 } 182 183 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, 184 const struct inet_diag_req_v2 *req) 185 { 186 return udp_dump_one(&udplite_table, in_skb, nlh, req); 187 } 188 189 static const struct inet_diag_handler udplite_diag_handler = { 190 .dump = udplite_diag_dump, 191 .dump_one = udplite_diag_dump_one, 192 .idiag_get_info = udp_diag_get_info, 193 .idiag_type = IPPROTO_UDPLITE, 194 .idiag_info_size = 0, 195 }; 196 197 static int __init udp_diag_init(void) 198 { 199 int err; 200 201 err = inet_diag_register(&udp_diag_handler); 202 if (err) 203 goto out; 204 err = inet_diag_register(&udplite_diag_handler); 205 if (err) 206 goto out_lite; 207 out: 208 return err; 209 out_lite: 210 inet_diag_unregister(&udp_diag_handler); 211 goto out; 212 } 213 214 static void __exit udp_diag_exit(void) 215 { 216 inet_diag_unregister(&udplite_diag_handler); 217 inet_diag_unregister(&udp_diag_handler); 218 } 219 220 module_init(udp_diag_init); 221 module_exit(udp_diag_exit); 222 MODULE_LICENSE("GPL"); 223 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */); 224 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */); 225