Commit 69ae5065 authored by Luiz Augusto von Dentz's avatar Luiz Augusto von Dentz
Browse files

Bluetooth: hci_sock: Forward credentials to monitor 



This stores scm_creds into hci_skb_cb so they can be properly forwarded
to the likes of btmon which is then able to print information about the
process who is originating the traffic:

bluetoothd[35]: @ MGMT Command: Rea.. (0x0001) plen 0  {0x0001}
@ MGMT Event: Command Complete (0x0001) plen 6         {0x0001}
      Read Management Version Information (0x0001) plen 3

bluetoothd[35]: < ACL Data T.. flags 0x00 dlen 41
      ATT: Write Command (0x52) len 36
        Handle: 0x0043 Type: ASE Control Point (0x2bc6)
          Data: 020203000110270000022800020a00409c0001000110270000022800020a00409c00
            Opcode: QoS Configuration (0x02)
            Number of ASE(s): 2
            ASE: #0
            ASE ID: 0x03
            CIG ID: 0x00
            CIS ID: 0x01
            SDU Interval: 10000 usec
            Framing: Unframed (0x00)
            PHY: 0x02
            LE 2M PHY (0x02)
            Max SDU: 40
            RTN: 2
            Max Transport Latency: 10
            Presentation Delay: 40000 us
            ASE: #1
            ASE ID: 0x01
            CIG ID: 0x00
            CIS ID: 0x01
            SDU Interval: 10000 usec
            Framing: Unframed (0x00)
            PHY: 0x02
            LE 2M PHY (0x02)
            Max SDU: 40
            RTN: 2
            Max Transport Latency: 10
            Presentation Delay: 40000 us

Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
parent 464c702f

include/net/bluetooth/bluetooth.h

+1 −0
Original line number Diff line number Diff line
@@ -471,6 +471,7 @@ struct bt_skb_cb { 
		struct sco_ctrl sco;

		struct hci_ctrl hci;

		struct mgmt_ctrl mgmt;

		struct scm_creds creds;

	};

};

#define bt_cb(skb) ((struct bt_skb_cb *)((skb)->cb))

net/bluetooth/hci_sock.c

+65 −2
Original line number Diff line number Diff line
@@ -264,6 +264,53 @@ void hci_send_to_sock(struct hci_dev *hdev, struct sk_buff *skb) 
	kfree_skb(skb_copy);

}



static void hci_sock_copy_creds(struct sock *sk, struct sk_buff *skb)

{

	struct scm_creds *creds;



	if (!sk || WARN_ON(!skb))

		return;



	creds = &bt_cb(skb)->creds;



	/* Check if peer credentials is set */

	if (!sk->sk_peer_pid) {

		/* Check if parent peer credentials is set */

		if (bt_sk(sk)->parent && bt_sk(sk)->parent->sk_peer_pid)

			sk = bt_sk(sk)->parent;

		else

			return;

	}



	/* Check if scm_creds already set */

	if (creds->pid == pid_vnr(sk->sk_peer_pid))

		return;



	memset(creds, 0, sizeof(*creds));



	creds->pid = pid_vnr(sk->sk_peer_pid);

	if (sk->sk_peer_cred) {

		creds->uid = sk->sk_peer_cred->uid;

		creds->gid = sk->sk_peer_cred->gid;

	}

}



static struct sk_buff *hci_skb_clone(struct sk_buff *skb)

{

	struct sk_buff *nskb;



	if (!skb)

		return NULL;



	nskb = skb_clone(skb, GFP_ATOMIC);

	if (!nskb)

		return NULL;



	hci_sock_copy_creds(skb->sk, nskb);



	return nskb;

}



/* Send frame to sockets with specific channel */

static void __hci_send_to_channel(unsigned short channel, struct sk_buff *skb,

				  int flag, struct sock *skip_sk)
@@ -289,7 +336,7 @@ static void __hci_send_to_channel(unsigned short channel, struct sk_buff *skb, 
		if (hci_pi(sk)->channel != channel)

			continue;



		nskb = skb_clone(skb, GFP_ATOMIC);

		nskb = hci_skb_clone(skb);

		if (!nskb)

			continue;
@@ -356,6 +403,8 @@ void hci_send_to_monitor(struct hci_dev *hdev, struct sk_buff *skb) 
	if (!skb_copy)

		return;



	hci_sock_copy_creds(skb->sk, skb_copy);



	/* Put header before the data */

	hdr = skb_push(skb_copy, HCI_MON_HDR_SIZE);

	hdr->opcode = opcode;
@@ -535,6 +584,8 @@ static struct sk_buff *create_monitor_ctrl_open(struct sock *sk) 
	if (!skb)

		return NULL;



	hci_sock_copy_creds(sk, skb);



	flags = hci_sock_test_flag(sk, HCI_SOCK_TRUSTED) ? 0x1 : 0x0;



	put_unaligned_le32(hci_pi(sk)->cookie, skb_put(skb, 4));
@@ -580,6 +631,8 @@ static struct sk_buff *create_monitor_ctrl_close(struct sock *sk) 
	if (!skb)

		return NULL;



	hci_sock_copy_creds(sk, skb);



	put_unaligned_le32(hci_pi(sk)->cookie, skb_put(skb, 4));



	__net_timestamp(skb);
@@ -606,6 +659,8 @@ static struct sk_buff *create_monitor_ctrl_command(struct sock *sk, u16 index, 
	if (!skb)

		return NULL;



	hci_sock_copy_creds(sk, skb);



	put_unaligned_le32(hci_pi(sk)->cookie, skb_put(skb, 4));

	put_unaligned_le16(opcode, skb_put(skb, 2));
@@ -638,6 +693,8 @@ send_monitor_note(struct sock *sk, const char *fmt, ...) 
	if (!skb)

		return;



	hci_sock_copy_creds(sk, skb);



	va_start(args, fmt);

	vsprintf(skb_put(skb, len), fmt, args);

	*(u8 *)skb_put(skb, 1) = 0;
@@ -1494,6 +1551,7 @@ static void hci_sock_cmsg(struct sock *sk, struct msghdr *msg, 
static int hci_sock_recvmsg(struct socket *sock, struct msghdr *msg,

			    size_t len, int flags)

{

	struct scm_cookie scm;

	struct sock *sk = sock->sk;

	struct sk_buff *skb;

	int copied, err;
@@ -1538,11 +1596,16 @@ static int hci_sock_recvmsg(struct socket *sock, struct msghdr *msg, 
		break;

	}



	memset(&scm, 0, sizeof(scm));

	scm.creds = bt_cb(skb)->creds;



	skb_free_datagram(sk, skb);



	if (flags & MSG_TRUNC)

		copied = skblen;



	scm_recv(sock, msg, &scm, flags);



	return err ? : copied;

}