#include <linux/types.h> #include <linux/spinlock.h> #include <linux/sock_diag.h> #include <linux/unix_diag.h> #include <linux/skbuff.h> #include <linux/module.h> #include <net/netlink.h> #include <net/af_unix.h> #include <net/tcp_states.h> static int sk_diag_dump_name(struct sock *sk, struct sk_buff *nlskb) { /* might or might not have unix_table_lock */ struct unix_address *addr = smp_load_acquire(&unix_sk(sk)->addr); if (!addr) return 0; return nla_put(nlskb, UNIX_DIAG_NAME, addr->len - sizeof(short), addr->name->sun_path); } static int sk_diag_dump_vfs(struct sock *sk, struct sk_buff *nlskb) { struct dentry *dentry = unix_sk(sk)->path.dentry; if (dentry) { struct unix_diag_vfs uv = { .udiag_vfs_ino = d_backing_inode(dentry)->i_ino, .udiag_vfs_dev = dentry->d_sb->s_dev, }; return nla_put(nlskb, UNIX_DIAG_VFS, sizeof(uv), &uv); } return 0; } static int sk_diag_dump_peer(struct sock *sk, struct sk_buff *nlskb) { struct sock *peer; int ino; peer = unix_peer_get(sk); if (peer) { unix_state_lock(peer); ino = sock_i_ino(peer); unix_state_unlock(peer); sock_put(peer); return nla_put_u32(nlskb, UNIX_DIAG_PEER, ino); } return 0; } static int sk_diag_dump_icons(struct sock *sk, struct sk_buff *nlskb) { struct sk_buff *skb; struct nlattr *attr; u32 *buf; int i; if (sk->sk_state == TCP_LISTEN) { spin_lock(&sk->sk_receive_queue.lock); attr = nla_reserve(nlskb, UNIX_DIAG_ICONS, sk->sk_receive_queue.qlen * sizeof(u32)); if (!attr) goto errout; buf = nla_data(attr); i = 0; skb_queue_walk(&sk->sk_receive_queue, skb) { struct sock *req, *peer; req = skb->sk; /* * The state lock is outer for the same sk's * queue lock. With the other's queue locked it's * OK to lock the state. */ unix_state_lock_nested(req); peer = unix_sk(req)->peer; buf[i++] = (peer ? sock_i_ino(peer) : 0); unix_state_unlock(req); } spin_unlock(&sk->sk_receive_queue.lock); } return 0; errout: spin_unlock(&sk->sk_receive_queue.lock); return -EMSGSIZE; } static int sk_diag_show_rqlen(struct sock *sk, struct sk_buff *nlskb) { struct unix_diag_rqlen rql; if (sk->sk_state == TCP_LISTEN) { rql.udiag_rqueue = sk->sk_receive_queue.qlen; rql.udiag_wqueue = sk->sk_max_ack_backlog; } else { rql.udiag_rqueue = (u32) unix_inq_len(sk); rql.udiag_wqueue = (u32) unix_outq_len(sk); } return nla_put(nlskb, UNIX_DIAG_RQLEN, sizeof(rql), &rql); } static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req, u32 portid, u32 seq, u32 flags, int sk_ino) { struct nlmsghdr *nlh; struct unix_diag_msg *rep; nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep), flags); if (!nlh) return -EMSGSIZE; rep = nlmsg_data(nlh); rep->udiag_family = AF_UNIX; rep->udiag_type = sk->sk_type; rep->udiag_state = sk->sk_state; rep->pad = 0; rep->udiag_ino = sk_ino; sock_diag_save_cookie(sk, rep->udiag_cookie); if ((req->udiag_show & UDIAG_SHOW_NAME) && sk_diag_dump_name(sk, skb)) goto out_nlmsg_trim; if ((req->udiag_show & UDIAG_SHOW_VFS) && sk_diag_dump_vfs(sk, skb)) goto out_nlmsg_trim; if ((req->udiag_show & UDIAG_SHOW_PEER) && sk_diag_dump_peer(sk, skb)) goto out_nlmsg_trim; if ((req->udiag_show & UDIAG_SHOW_ICONS) && sk_diag_dump_icons(sk, skb)) goto out_nlmsg_trim; if ((req->udiag_show & UDIAG_SHOW_RQLEN) && sk_diag_show_rqlen(sk, skb)) goto out_nlmsg_trim; if ((req->udiag_show & UDIAG_SHOW_MEMINFO) && sock_diag_put_meminfo(sk, skb, UNIX_DIAG_MEMINFO)) goto out_nlmsg_trim; if (nla_put_u8(skb, UNIX_DIAG_SHUTDOWN, sk->sk_shutdown)) goto out_nlmsg_trim; nlmsg_end(skb, nlh); return 0; out_nlmsg_trim: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req, u32 portid, u32 seq, u32 flags) { int sk_ino; unix_state_lock(sk); sk_ino = sock_i_ino(sk); unix_state_unlock(sk); if (!sk_ino) return 0; return sk_diag_fill(sk, skb, req, portid, seq, flags, sk_ino); } static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) { struct unix_diag_req *req; int num, s_num, slot, s_slot; struct net *net = sock_net(skb->sk); req = nlmsg_data(cb->nlh); s_slot = cb->args[0]; num = s_num = cb->args[1]; spin_lock(&unix_table_lock); for (slot = s_slot; slot < ARRAY_SIZE(unix_socket_table); s_num = 0, slot++) { struct sock *sk; num = 0; sk_for_each(sk, &unix_socket_table[slot]) { if (!net_eq(sock_net(sk), net)) continue; if (num < s_num) goto next; if (!(req->udiag_states & (1 << sk->sk_state))) goto next; if (sk_diag_dump(sk, skb, req, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI) < 0) goto done; next: num++; } } done: spin_unlock(&unix_table_lock); cb->args[0] = slot; cb->args[1] = num; return skb->len; } static struct sock *unix_lookup_by_ino(unsigned int ino) { int i; struct sock *sk; spin_lock(&unix_table_lock); for (i = 0; i < ARRAY_SIZE(unix_socket_table); i++) { sk_for_each(sk, &unix_socket_table[i]) if (ino == sock_i_ino(sk)) { sock_hold(sk); spin_unlock(&unix_table_lock); return sk; } } spin_unlock(&unix_table_lock); return NULL; } static int unix_diag_get_exact(struct sk_buff *in_skb, const struct nlmsghdr *nlh, struct unix_diag_req *req) { int err = -EINVAL; struct sock *sk; struct sk_buff *rep; unsigned int extra_len; struct net *net = sock_net(in_skb->sk); if (req->udiag_ino == 0) goto out_nosk; sk = unix_lookup_by_ino(req->udiag_ino); err = -ENOENT; if (sk == NULL) goto out_nosk; if (!net_eq(sock_net(sk), net)) goto out; err = sock_diag_check_cookie(sk, req->udiag_cookie); if (err) goto out; extra_len = 256; again: err = -ENOMEM; rep = nlmsg_new(sizeof(struct unix_diag_msg) + extra_len, GFP_KERNEL); if (!rep) goto out; err = sk_diag_fill(sk, rep, req, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, 0, req->udiag_ino); if (err < 0) { nlmsg_free(rep); extra_len += 256; if (extra_len >= PAGE_SIZE) goto out; goto again; } err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, MSG_DONTWAIT); if (err > 0) err = 0; out: if (sk) sock_put(sk); out_nosk: return err; } static int unix_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) { int hdrlen = sizeof(struct unix_diag_req); struct net *net = sock_net(skb->sk); if (nlmsg_len(h) < hdrlen) return -EINVAL; if (h->nlmsg_flags & NLM_F_DUMP) { struct netlink_dump_control c = { .dump = unix_diag_dump, }; return netlink_dump_start(net->diag_nlsk, skb, h, &c); } else return unix_diag_get_exact(skb, h, nlmsg_data(h)); } static const struct sock_diag_handler unix_diag_handler = { .family = AF_UNIX, .dump = unix_diag_handler_dump, }; static int __init unix_diag_init(void) { return sock_diag_register(&unix_diag_handler); } static void __exit unix_diag_exit(void) { sock_diag_unregister(&unix_diag_handler); } module_init(unix_diag_init); module_exit(unix_diag_exit); MODULE_LICENSE("GPL"); MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 1 /* AF_LOCAL */);