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#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/sock_diag.h>
#include <linux/unix_diag.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/af_unix.h>
#include <net/tcp_states.h>
#define UNIX_DIAG_PUT(skb, attrtype, attrlen) \
RTA_DATA(__RTA_PUT(skb, attrtype, attrlen))
static int sk_diag_dump_name(struct sock *sk, struct sk_buff *nlskb)
{
struct unix_address *addr = unix_sk(sk)->addr;
char *s;
if (addr) {
s = UNIX_DIAG_PUT(nlskb, UNIX_DIAG_NAME, addr->len - sizeof(short));
memcpy(s, addr->name->sun_path, addr->len - sizeof(short));
}
return 0;
rtattr_failure:
return -EMSGSIZE;
}
static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
u32 pid, u32 seq, u32 flags, int sk_ino)
{
unsigned char *b = skb_tail_pointer(skb);
struct nlmsghdr *nlh;
struct unix_diag_msg *rep;
nlh = NLMSG_PUT(skb, pid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep));
nlh->nlmsg_flags = flags;
rep = NLMSG_DATA(nlh);
rep->udiag_family = AF_UNIX;
rep->udiag_type = sk->sk_type;
rep->udiag_state = sk->sk_state;
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 nlmsg_failure;
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
return skb->len;
nlmsg_failure:
nlmsg_trim(skb, b);
return -EMSGSIZE;
}
static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
u32 pid, 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, pid, 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;
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 <= UNIX_HASH_SIZE; s_num = 0, slot++) {
struct sock *sk;
struct hlist_node *node;
num = 0;
sk_for_each(sk, node, &unix_socket_table[slot]) {
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).pid,
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(int ino)
{
int i;
struct sock *sk;
spin_lock(&unix_table_lock);
for (i = 0; i <= UNIX_HASH_SIZE; i++) {
struct hlist_node *node;
sk_for_each(sk, node, &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;
if (req->udiag_ino == 0)
goto out_nosk;
sk = unix_lookup_by_ino(req->udiag_ino);
err = -ENOENT;
if (sk == NULL)
goto out_nosk;
err = sock_diag_check_cookie(sk, req->udiag_cookie);
if (err)
goto out;
extra_len = 256;
again:
err = -ENOMEM;
rep = alloc_skb(NLMSG_SPACE((sizeof(struct unix_diag_msg) + extra_len)),
GFP_KERNEL);
if (!rep)
goto out;
err = sk_diag_fill(sk, rep, req, NETLINK_CB(in_skb).pid,
nlh->nlmsg_seq, 0, req->udiag_ino);
if (err < 0) {
kfree_skb(rep);
extra_len += 256;
if (extra_len >= PAGE_SIZE)
goto out;
goto again;
}
err = netlink_unicast(sock_diag_nlsk, rep, NETLINK_CB(in_skb).pid,
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);
if (nlmsg_len(h) < hdrlen)
return -EINVAL;
if (h->nlmsg_flags & NLM_F_DUMP)
return netlink_dump_start(sock_diag_nlsk, skb, h,
unix_diag_dump, NULL, 0);
else
return unix_diag_get_exact(skb, h, (struct unix_diag_req *)NLMSG_DATA(h));
}
static 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 */);
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