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 = d_backing_inode(dentry)->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->pad = 0; 128 rep->udiag_ino = sk_ino; 129 sock_diag_save_cookie(sk, rep->udiag_cookie); 130 131 if ((req->udiag_show & UDIAG_SHOW_NAME) && 132 sk_diag_dump_name(sk, skb)) 133 goto out_nlmsg_trim; 134 135 if ((req->udiag_show & UDIAG_SHOW_VFS) && 136 sk_diag_dump_vfs(sk, skb)) 137 goto out_nlmsg_trim; 138 139 if ((req->udiag_show & UDIAG_SHOW_PEER) && 140 sk_diag_dump_peer(sk, skb)) 141 goto out_nlmsg_trim; 142 143 if ((req->udiag_show & UDIAG_SHOW_ICONS) && 144 sk_diag_dump_icons(sk, skb)) 145 goto out_nlmsg_trim; 146 147 if ((req->udiag_show & UDIAG_SHOW_RQLEN) && 148 sk_diag_show_rqlen(sk, skb)) 149 goto out_nlmsg_trim; 150 151 if ((req->udiag_show & UDIAG_SHOW_MEMINFO) && 152 sock_diag_put_meminfo(sk, skb, UNIX_DIAG_MEMINFO)) 153 goto out_nlmsg_trim; 154 155 if (nla_put_u8(skb, UNIX_DIAG_SHUTDOWN, sk->sk_shutdown)) 156 goto out_nlmsg_trim; 157 158 nlmsg_end(skb, nlh); 159 return 0; 160 161 out_nlmsg_trim: 162 nlmsg_cancel(skb, nlh); 163 return -EMSGSIZE; 164 } 165 166 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req, 167 u32 portid, u32 seq, u32 flags) 168 { 169 int sk_ino; 170 171 unix_state_lock(sk); 172 sk_ino = sock_i_ino(sk); 173 unix_state_unlock(sk); 174 175 if (!sk_ino) 176 return 0; 177 178 return sk_diag_fill(sk, skb, req, portid, seq, flags, sk_ino); 179 } 180 181 static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) 182 { 183 struct unix_diag_req *req; 184 int num, s_num, slot, s_slot; 185 struct net *net = sock_net(skb->sk); 186 187 req = nlmsg_data(cb->nlh); 188 189 s_slot = cb->args[0]; 190 num = s_num = cb->args[1]; 191 192 spin_lock(&unix_table_lock); 193 for (slot = s_slot; 194 slot < ARRAY_SIZE(unix_socket_table); 195 s_num = 0, slot++) { 196 struct sock *sk; 197 198 num = 0; 199 sk_for_each(sk, &unix_socket_table[slot]) { 200 if (!net_eq(sock_net(sk), net)) 201 continue; 202 if (num < s_num) 203 goto next; 204 if (!(req->udiag_states & (1 << sk->sk_state))) 205 goto next; 206 if (sk_diag_dump(sk, skb, req, 207 NETLINK_CB(cb->skb).portid, 208 cb->nlh->nlmsg_seq, 209 NLM_F_MULTI) < 0) 210 goto done; 211 next: 212 num++; 213 } 214 } 215 done: 216 spin_unlock(&unix_table_lock); 217 cb->args[0] = slot; 218 cb->args[1] = num; 219 220 return skb->len; 221 } 222 223 static struct sock *unix_lookup_by_ino(int ino) 224 { 225 int i; 226 struct sock *sk; 227 228 spin_lock(&unix_table_lock); 229 for (i = 0; i < ARRAY_SIZE(unix_socket_table); i++) { 230 sk_for_each(sk, &unix_socket_table[i]) 231 if (ino == sock_i_ino(sk)) { 232 sock_hold(sk); 233 spin_unlock(&unix_table_lock); 234 235 return sk; 236 } 237 } 238 239 spin_unlock(&unix_table_lock); 240 return NULL; 241 } 242 243 static int unix_diag_get_exact(struct sk_buff *in_skb, 244 const struct nlmsghdr *nlh, 245 struct unix_diag_req *req) 246 { 247 int err = -EINVAL; 248 struct sock *sk; 249 struct sk_buff *rep; 250 unsigned int extra_len; 251 struct net *net = sock_net(in_skb->sk); 252 253 if (req->udiag_ino == 0) 254 goto out_nosk; 255 256 sk = unix_lookup_by_ino(req->udiag_ino); 257 err = -ENOENT; 258 if (sk == NULL) 259 goto out_nosk; 260 261 err = sock_diag_check_cookie(sk, req->udiag_cookie); 262 if (err) 263 goto out; 264 265 extra_len = 256; 266 again: 267 err = -ENOMEM; 268 rep = nlmsg_new(sizeof(struct unix_diag_msg) + extra_len, GFP_KERNEL); 269 if (!rep) 270 goto out; 271 272 err = sk_diag_fill(sk, rep, req, NETLINK_CB(in_skb).portid, 273 nlh->nlmsg_seq, 0, req->udiag_ino); 274 if (err < 0) { 275 nlmsg_free(rep); 276 extra_len += 256; 277 if (extra_len >= PAGE_SIZE) 278 goto out; 279 280 goto again; 281 } 282 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, 283 MSG_DONTWAIT); 284 if (err > 0) 285 err = 0; 286 out: 287 if (sk) 288 sock_put(sk); 289 out_nosk: 290 return err; 291 } 292 293 static int unix_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) 294 { 295 int hdrlen = sizeof(struct unix_diag_req); 296 struct net *net = sock_net(skb->sk); 297 298 if (nlmsg_len(h) < hdrlen) 299 return -EINVAL; 300 301 if (h->nlmsg_flags & NLM_F_DUMP) { 302 struct netlink_dump_control c = { 303 .dump = unix_diag_dump, 304 }; 305 return netlink_dump_start(net->diag_nlsk, skb, h, &c); 306 } else 307 return unix_diag_get_exact(skb, h, nlmsg_data(h)); 308 } 309 310 static const struct sock_diag_handler unix_diag_handler = { 311 .family = AF_UNIX, 312 .dump = unix_diag_handler_dump, 313 }; 314 315 static int __init unix_diag_init(void) 316 { 317 return sock_diag_register(&unix_diag_handler); 318 } 319 320 static void __exit unix_diag_exit(void) 321 { 322 sock_diag_unregister(&unix_diag_handler); 323 } 324 325 module_init(unix_diag_init); 326 module_exit(unix_diag_exit); 327 MODULE_LICENSE("GPL"); 328 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 1 /* AF_LOCAL */); 329