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 pid, u32 seq, u32 flags, int sk_ino) 114 { 115 struct nlmsghdr *nlh; 116 struct unix_diag_msg *rep; 117 118 nlh = nlmsg_put(skb, pid, 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 return nlmsg_end(skb, nlh); 155 156 out_nlmsg_trim: 157 nlmsg_cancel(skb, nlh); 158 return -EMSGSIZE; 159 } 160 161 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req, 162 u32 pid, u32 seq, u32 flags) 163 { 164 int sk_ino; 165 166 unix_state_lock(sk); 167 sk_ino = sock_i_ino(sk); 168 unix_state_unlock(sk); 169 170 if (!sk_ino) 171 return 0; 172 173 return sk_diag_fill(sk, skb, req, pid, seq, flags, sk_ino); 174 } 175 176 static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) 177 { 178 struct unix_diag_req *req; 179 int num, s_num, slot, s_slot; 180 struct net *net = sock_net(skb->sk); 181 182 req = nlmsg_data(cb->nlh); 183 184 s_slot = cb->args[0]; 185 num = s_num = cb->args[1]; 186 187 spin_lock(&unix_table_lock); 188 for (slot = s_slot; 189 slot < ARRAY_SIZE(unix_socket_table); 190 s_num = 0, slot++) { 191 struct sock *sk; 192 struct hlist_node *node; 193 194 num = 0; 195 sk_for_each(sk, node, &unix_socket_table[slot]) { 196 if (!net_eq(sock_net(sk), net)) 197 continue; 198 if (num < s_num) 199 goto next; 200 if (!(req->udiag_states & (1 << sk->sk_state))) 201 goto next; 202 if (sk_diag_dump(sk, skb, req, 203 NETLINK_CB(cb->skb).pid, 204 cb->nlh->nlmsg_seq, 205 NLM_F_MULTI) < 0) 206 goto done; 207 next: 208 num++; 209 } 210 } 211 done: 212 spin_unlock(&unix_table_lock); 213 cb->args[0] = slot; 214 cb->args[1] = num; 215 216 return skb->len; 217 } 218 219 static struct sock *unix_lookup_by_ino(int ino) 220 { 221 int i; 222 struct sock *sk; 223 224 spin_lock(&unix_table_lock); 225 for (i = 0; i < ARRAY_SIZE(unix_socket_table); i++) { 226 struct hlist_node *node; 227 228 sk_for_each(sk, node, &unix_socket_table[i]) 229 if (ino == sock_i_ino(sk)) { 230 sock_hold(sk); 231 spin_unlock(&unix_table_lock); 232 233 return sk; 234 } 235 } 236 237 spin_unlock(&unix_table_lock); 238 return NULL; 239 } 240 241 static int unix_diag_get_exact(struct sk_buff *in_skb, 242 const struct nlmsghdr *nlh, 243 struct unix_diag_req *req) 244 { 245 int err = -EINVAL; 246 struct sock *sk; 247 struct sk_buff *rep; 248 unsigned int extra_len; 249 struct net *net = sock_net(in_skb->sk); 250 251 if (req->udiag_ino == 0) 252 goto out_nosk; 253 254 sk = unix_lookup_by_ino(req->udiag_ino); 255 err = -ENOENT; 256 if (sk == NULL) 257 goto out_nosk; 258 259 err = sock_diag_check_cookie(sk, req->udiag_cookie); 260 if (err) 261 goto out; 262 263 extra_len = 256; 264 again: 265 err = -ENOMEM; 266 rep = nlmsg_new(sizeof(struct unix_diag_msg) + extra_len, GFP_KERNEL); 267 if (!rep) 268 goto out; 269 270 err = sk_diag_fill(sk, rep, req, NETLINK_CB(in_skb).pid, 271 nlh->nlmsg_seq, 0, req->udiag_ino); 272 if (err < 0) { 273 nlmsg_free(rep); 274 extra_len += 256; 275 if (extra_len >= PAGE_SIZE) 276 goto out; 277 278 goto again; 279 } 280 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).pid, 281 MSG_DONTWAIT); 282 if (err > 0) 283 err = 0; 284 out: 285 if (sk) 286 sock_put(sk); 287 out_nosk: 288 return err; 289 } 290 291 static int unix_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) 292 { 293 int hdrlen = sizeof(struct unix_diag_req); 294 struct net *net = sock_net(skb->sk); 295 296 if (nlmsg_len(h) < hdrlen) 297 return -EINVAL; 298 299 if (h->nlmsg_flags & NLM_F_DUMP) { 300 struct netlink_dump_control c = { 301 .dump = unix_diag_dump, 302 }; 303 return netlink_dump_start(net->diag_nlsk, skb, h, &c); 304 } else 305 return unix_diag_get_exact(skb, h, nlmsg_data(h)); 306 } 307 308 static const struct sock_diag_handler unix_diag_handler = { 309 .family = AF_UNIX, 310 .dump = unix_diag_handler_dump, 311 }; 312 313 static int __init unix_diag_init(void) 314 { 315 return sock_diag_register(&unix_diag_handler); 316 } 317 318 static void __exit unix_diag_exit(void) 319 { 320 sock_diag_unregister(&unix_diag_handler); 321 } 322 323 module_init(unix_diag_init); 324 module_exit(unix_diag_exit); 325 MODULE_LICENSE("GPL"); 326 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 1 /* AF_LOCAL */); 327