unix_diag: Unix socket name NLA

Report the sun_path when requested as NLA. With leading '\0' if
present but without the leading AF_UNIX bits.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/unix_diag.h b/include/linux/unix_diag.h
index 445184a857638e2eb7ef89fd4ea910696420335c..cc4df34d4c14390c4f2ec83185c6fc3f80531d81 100644 (file)
--- a/include/linux/unix_diag.h
+++ b/include/linux/unix_diag.h
@@ -11,6 +11,8 @@ struct unix_diag_req {
        __u32   udiag_cookie[2];
 };
 
+#define UDIAG_SHOW_NAME                0x00000001      /* show name (not path) */
+
 struct unix_diag_msg {
        __u8    udiag_family;
        __u8    udiag_type;
@@ -21,4 +23,10 @@ struct unix_diag_msg {
        __u32   udiag_cookie[2];
 };
 
+enum {
+       UNIX_DIAG_NAME,
+
+       UNIX_DIAG_MAX,
+};
+
 #endif

diff --git a/net/unix/diag.c b/net/unix/diag.c
index d7bd48c49ee559d5073369e28c0025ac4b747155..161ce6c05e3140b1830195317ce6887a38a354f0 100644 (file)
--- a/net/unix/diag.c
+++ b/net/unix/diag.c
@@ -10,6 +10,22 @@
 #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)
 {
@@ -28,6 +44,10 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_r
        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;