1 #include <linux/types.h> 2 #include <linux/spinlock.h> 3 #include <linux/sock_diag.h> 4 #include <linux/unix_diag.h> 5 #include <linux/skbuff.h> 6 #include <linux/module.h> 7 #include <net/netlink.h> 8 #include <net/af_unix.h> 9 #include <net/tcp_states.h> 10 11 static int sk_diag_dump_name(struct sock *sk, struct sk_buff *nlskb) 12 { 13 struct unix_address *addr = unix_sk(sk)->addr; 14 15 if (!addr) 16 return 0; 17 18 return nla_put(nlskb, UNIX_DIAG_NAME, addr->len - sizeof(short), 19 addr->name->sun_path); 20 } 21 22 static int sk_diag_dump_vfs(struct sock *sk, struct sk_buff *nlskb) 23 { 24 struct dentry *dentry = unix_sk(sk)->path.dentry; 25 26 if (dentry) { 27 struct unix_diag_vfs uv = { 28 .udiag_vfs_ino = dentry->d_inode->i_ino, 29 .udiag_vfs_dev = dentry->d_sb->s_dev, 30 }; 31 32 return nla_put(nlskb, UNIX_DIAG_VFS, sizeof(uv), &uv); 33 } 34 35 return 0; 36 } 37 38 static int sk_diag_dump_peer(struct sock *sk, struct sk_buff *nlskb) 39 { 40 struct sock *peer; 41 int ino; 42 43 peer = unix_peer_get(sk); 44 if (peer) { 45 unix_state_lock(peer); 46 ino = sock_i_ino(peer); 47 unix_state_unlock(peer); 48 sock_put(peer); 49 50 return nla_put_u32(nlskb, UNIX_DIAG_PEER, ino); 51 } 52 53 return 0; 54 } 55 56 static int sk_diag_dump_icons(struct sock *sk, struct sk_buff *nlskb) 57 { 58 struct sk_buff *skb; 59 struct nlattr *attr; 60 u32 *buf; 61 int i; 62 63 if (sk->sk_state == TCP_LISTEN) { 64 spin_lock(&sk->sk_receive_queue.lock); 65 66 attr = nla_reserve(nlskb, UNIX_DIAG_ICONS, 67 sk->sk_receive_queue.qlen * sizeof(u32)); 68 if (!attr) 69 goto errout; 70 71 buf = nla_data(attr); 72 i = 0; 73 skb_queue_walk(&sk->sk_receive_queue, skb) { 74 struct sock *req, *peer; 75 76 req = skb->sk; 77 /* 78 * The state lock is outer for the same sk's 79 * queue lock. With the other's queue locked it's 80 * OK to lock the state. 81 */ 82 unix_state_lock_nested(req); 83 peer = unix_sk(req)->peer; 84 buf[i++] = (peer ? sock_i_ino(peer) : 0); 85 unix_state_unlock(req); 86 } 87 spin_unlock(&sk->sk_receive_queue.lock); 88 } 89 90 return 0; 91 92 errout: 93 spin_unlock(&sk->sk_receive_queue.lock); 94 return -EMSGSIZE; 95 } 96 97 static int sk_diag_show_rqlen(struct sock *sk, struct sk_buff *nlskb) 98 { 99 struct unix_diag_rqlen rql; 100 101 if (sk->sk_state == TCP_LISTEN) { 102 rql.udiag_rqueue = sk->sk_receive_queue.qlen; 103 rql.udiag_wqueue = sk->sk_max_ack_backlog; 104 } else { 105 rql.udiag_rqueue = (u32) unix_inq_len(sk); 106 rql.udiag_wqueue = (u32) unix_outq_len(sk); 107 } 108 109 return nla_put(nlskb, UNIX_DIAG_RQLEN, sizeof(rql), &rql); 110 } 111 112 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req, 113 u32 portid, u32 seq, u32 flags, int sk_ino) 114 { 115 struct nlmsghdr *nlh; 116 struct unix_diag_msg *rep; 117 118 nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep), 119 flags); 120 if (!nlh) 121 return -EMSGSIZE; 122 123 rep = nlmsg_data(nlh); 124 rep->udiag_family = AF_UNIX; 125 rep->udiag_type = sk->sk_type; 126 rep->udiag_state = sk->sk_state; 127 rep->udiag_ino = sk_ino; 128 sock_diag_save_cookie(sk, rep->udiag_cookie); 129 130 if ((req->udiag_show & UDIAG_SHOW_NAME) && 131 sk_diag_dump_name(sk, skb)) 132 goto out_nlmsg_trim; 133 134 if ((req->udiag_show & UDIAG_SHOW_VFS) && 135 sk_diag_dump_vfs(sk, skb)) 136 goto out_nlmsg_trim; 137 138 if ((req->udiag_show & UDIAG_SHOW_PEER) && 139 sk_diag_dump_peer(sk, skb)) 140 goto out_nlmsg_trim; 141 142 if ((req->udiag_show & UDIAG_SHOW_ICONS) && 143 sk_diag_dump_icons(sk, skb)) 144 goto out_nlmsg_trim; 145 146 if ((req->udiag_show & UDIAG_SHOW_RQLEN) && 147 sk_diag_show_rqlen(sk, skb)) 148 goto out_nlmsg_trim; 149 150 if ((req->udiag_show & UDIAG_SHOW_MEMINFO) && 151 sock_diag_put_meminfo(sk, skb, UNIX_DIAG_MEMINFO)) 152 goto out_nlmsg_trim; 153 154 if (nla_put_u8(skb, UNIX_DIAG_SHUTDOWN, sk->sk_shutdown)) 155 goto out_nlmsg_trim; 156 157 return nlmsg_end(skb, nlh); 158 159 out_nlmsg_trim: 160 nlmsg_cancel(skb, nlh); 161 return -EMSGSIZE; 162 } 163 164 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req, 165 u32 portid, u32 seq, u32 flags) 166 { 167 int sk_ino; 168 169 unix_state_lock(sk); 170 sk_ino = sock_i_ino(sk); 171 unix_state_unlock(sk); 172 173 if (!sk_ino) 174 return 0; 175 176 return sk_diag_fill(sk, skb, req, portid, seq, flags, sk_ino); 177 } 178 179 static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) 180 { 181 struct unix_diag_req *req; 182 int num, s_num, slot, s_slot; 183 struct net *net = sock_net(skb->sk); 184 185 req = nlmsg_data(cb->nlh); 186 187 s_slot = cb->args[0]; 188 num = s_num = cb->args[1]; 189 190 spin_lock(&unix_table_lock); 191 for (slot = s_slot; 192 slot < ARRAY_SIZE(unix_socket_table); 193 s_num = 0, slot++) { 194 struct sock *sk; 195 struct hlist_node *node; 196 197 num = 0; 198 sk_for_each(sk, node, &unix_socket_table[slot]) { 199 if (!net_eq(sock_net(sk), net)) 200 continue; 201 if (num < s_num) 202 goto next; 203 if (!(req->udiag_states & (1 << sk->sk_state))) 204 goto next; 205 if (sk_diag_dump(sk, skb, req, 206 NETLINK_CB(cb->skb).portid, 207 cb->nlh->nlmsg_seq, 208 NLM_F_MULTI) < 0) 209 goto done; 210 next: 211 num++; 212 } 213 } 214 done: 215 spin_unlock(&unix_table_lock); 216 cb->args[0] = slot; 217 cb->args[1] = num; 218 219 return skb->len; 220 } 221 222 static struct sock *unix_lookup_by_ino(int ino) 223 { 224 int i; 225 struct sock *sk; 226 227 spin_lock(&unix_table_lock); 228 for (i = 0; i < ARRAY_SIZE(unix_socket_table); i++) { 229 struct hlist_node *node; 230 231 sk_for_each(sk, node, &unix_socket_table[i]) 232 if (ino == sock_i_ino(sk)) { 233 sock_hold(sk); 234 spin_unlock(&unix_table_lock); 235 236 return sk; 237 } 238 } 239 240 spin_unlock(&unix_table_lock); 241 return NULL; 242 } 243 244 static int unix_diag_get_exact(struct sk_buff *in_skb, 245 const struct nlmsghdr *nlh, 246 struct unix_diag_req *req) 247 { 248 int err = -EINVAL; 249 struct sock *sk; 250 struct sk_buff *rep; 251 unsigned int extra_len; 252 struct net *net = sock_net(in_skb->sk); 253 254 if (req->udiag_ino == 0) 255 goto out_nosk; 256 257 sk = unix_lookup_by_ino(req->udiag_ino); 258 err = -ENOENT; 259 if (sk == NULL) 260 goto out_nosk; 261 262 err = sock_diag_check_cookie(sk, req->udiag_cookie); 263 if (err) 264 goto out; 265 266 extra_len = 256; 267 again: 268 err = -ENOMEM; 269 rep = nlmsg_new(sizeof(struct unix_diag_msg) + extra_len, GFP_KERNEL); 270 if (!rep) 271 goto out; 272 273 err = sk_diag_fill(sk, rep, req, NETLINK_CB(in_skb).portid, 274 nlh->nlmsg_seq, 0, req->udiag_ino); 275 if (err < 0) { 276 nlmsg_free(rep); 277 extra_len += 256; 278 if (extra_len >= PAGE_SIZE) 279 goto out; 280 281 goto again; 282 } 283 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 284 MSG_DONTWAIT); 285 if (err > 0) 286 err = 0; 287 out: 288 if (sk) 289 sock_put(sk); 290 out_nosk: 291 return err; 292 } 293 294 static int unix_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) 295 { 296 int hdrlen = sizeof(struct unix_diag_req); 297 struct net *net = sock_net(skb->sk); 298 299 if (nlmsg_len(h) < hdrlen) 300 return -EINVAL; 301 302 if (h->nlmsg_flags & NLM_F_DUMP) { 303 struct netlink_dump_control c = { 304 .dump = unix_diag_dump, 305 }; 306 return netlink_dump_start(net->diag_nlsk, skb, h, &c); 307 } else 308 return unix_diag_get_exact(skb, h, nlmsg_data(h)); 309 } 310 311 static const struct sock_diag_handler unix_diag_handler = { 312 .family = AF_UNIX, 313 .dump = unix_diag_handler_dump, 314 }; 315 316 static int __init unix_diag_init(void) 317 { 318 return sock_diag_register(&unix_diag_handler); 319 } 320 321 static void __exit unix_diag_exit(void) 322 { 323 sock_diag_unregister(&unix_diag_handler); 324 } 325 326 module_init(unix_diag_init); 327 module_exit(unix_diag_exit); 328 MODULE_LICENSE("GPL"); 329 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 1 /* AF_LOCAL */); 330