Return-Path: <cyrus@holtmann.org>
Date: Wed, 9 Nov 2011 15:24:11 -0200
From: Gustavo Padovan <padovan@profusion.mobi>
To: Brian Gix <bgix@codeaurora.org>
Cc: linux-bluetooth@vger.kernel.org
Subject: Re: [PATCH 1/1] Bluetooth: Add support for LE Passkeys to MGMTOPS
Message-ID: <20111109172411.GA2672@joana>
References: <1320855666-8471-1-git-send-email-bgix@codeaurora.org>
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In-Reply-To: <1320855666-8471-1-git-send-email-bgix@codeaurora.org>
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Hi Brian,

* Brian Gix <bgix@codeaurora.org> [2011-11-09 08:21:06 -0800]:

> LE pairing is a Host based algorythm that requires User entered
> passkeys to obtain Man-In-The-Middle (MITM) level protection,
> unlike it's BR/EDR based conterpart SSP. This interface addition
> enables this ability.
> 
> Signed-off-by: Brian Gix <bgix@codeaurora.org>
> ---
>  include/net/bluetooth/mgmt.h |   11 ++++++
>  net/bluetooth/mgmt.c         |   77 ++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 86 insertions(+), 2 deletions(-)
> 
> diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
> index 3e320c9..d67683f 100644
> --- a/include/net/bluetooth/mgmt.h
> +++ b/include/net/bluetooth/mgmt.h
> @@ -228,6 +228,17 @@ struct mgmt_cp_set_fast_connectable {
>  	__u8 enable;
>  } __packed;
>  
> +#define MGMT_OP_USER_PASSKEY_REPLY	0x0020
> +struct mgmt_cp_user_passkey_reply {
> +	bdaddr_t bdaddr;
> +	__le32 passkey;
> +} __packed;
> +
> +#define MGMT_OP_USER_PASSKEY_NEG_REPLY	0x0021
> +struct mgmt_cp_user_passkey_neg_reply {
> +	bdaddr_t bdaddr;
> +} __packed;
> +
>  #define MGMT_EV_CMD_COMPLETE		0x0001
>  struct mgmt_ev_cmd_complete {
>  	__le16 opcode;
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index 4cb2f95..c61b31e 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -1429,6 +1429,7 @@ static int user_confirm_reply(struct sock *sk, u16 index, unsigned char *data,
>  	u16 mgmt_op, hci_op;
>  	struct pending_cmd *cmd;
>  	struct hci_dev *hdev;
> +	struct hci_conn *conn;
>  	int err;
>  
>  	BT_DBG("");
> @@ -1452,19 +1453,85 @@ static int user_confirm_reply(struct sock *sk, u16 index, unsigned char *data,
>  
>  	if (!test_bit(HCI_UP, &hdev->flags)) {
>  		err = cmd_status(sk, index, mgmt_op, ENETDOWN);
> -		goto failed;
> +		goto done;
> +	}
> +
> +	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &cp->bdaddr);
> +	if (!conn) {
> +		conn = hci_conn_hash_lookup_ba(hdev, LE_LINK, &cp->bdaddr);
> +		if (!conn) {
> +			err = cmd_status(sk, index, mgmt_op, ENOTCONN);
> +			goto done;
> +		}
> +
> +		/* Forward Confirm response to SMP */
> +
> +		err = cmd_status(sk, index, mgmt_op, 0);
> +		goto done;

user_confirm_reply changes should be in a separate commit. Let's not mix
things here.

>  	}
>  
>  	cmd = mgmt_pending_add(sk, mgmt_op, index, data, len);
>  	if (!cmd) {
>  		err = -ENOMEM;
> -		goto failed;
> +		goto done;
>  	}
>  
>  	err = hci_send_cmd(hdev, hci_op, sizeof(cp->bdaddr), &cp->bdaddr);
>  	if (err < 0)
>  		mgmt_pending_remove(cmd);
>  
> +done:
> +	hci_dev_unlock_bh(hdev);
> +	hci_dev_put(hdev);
> +
> +	return err;
> +}
> +
> +static int user_passkey_reply(struct sock *sk, u16 index, unsigned char *data,
> +							u16 len, int success)
> +{
> +	struct mgmt_cp_user_passkey_reply *cp = (void *) data;
> +	u16 mgmt_op;
> +	u32 passkey = 0;
> +	struct hci_dev *hdev;
> +	struct hci_conn *conn;
> +	int expected_len, err = 0;
> +
> +	BT_DBG("");
> +
> +	if (success) {
> +		mgmt_op = MGMT_OP_USER_PASSKEY_REPLY;
> +		expected_len = sizeof(*cp);
> +		passkey = le32_to_cpu(cp->passkey);
> +	} else {
> +		mgmt_op = MGMT_OP_USER_PASSKEY_NEG_REPLY;
> +		expected_len = sizeof(struct mgmt_cp_user_passkey_neg_reply);
> +	}
> +
> +	if (len != expected_len)
> +		return cmd_status(sk, index, mgmt_op, EINVAL);
> +
> +	hdev = hci_dev_get(index);
> +	if (!hdev)
> +		return cmd_status(sk, index, mgmt_op, ENODEV);
> +
> +	hci_dev_lock_bh(hdev);
> +
> +	if (!test_bit(HCI_UP, &hdev->flags)) {
> +		err = cmd_status(sk, index, mgmt_op, ENETDOWN);
> +		goto failed;
> +	}
> +
> +	conn = hci_conn_hash_lookup_ba(hdev, LE_LINK, &cp->bdaddr);
> +	if (!conn) {
> +		err = cmd_status(sk, index, mgmt_op, ENOTCONN);
> +		goto failed;
> +	}
> +
> +	/* Forward Passkey response to SMP */

Passkey reply should work for both BR/EDR and LE, so let's do this a way that
it works for both with the same command.

	Gustavo