1745 строки
41 KiB
C
1745 строки
41 KiB
C
/*
|
|
BlueZ - Bluetooth protocol stack for Linux
|
|
Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License version 2 as
|
|
published by the Free Software Foundation;
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
|
|
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
|
|
IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
|
|
CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
|
|
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
|
|
ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
|
|
COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
|
|
SOFTWARE IS DISCLAIMED.
|
|
*/
|
|
|
|
#include <linux/crypto.h>
|
|
#include <linux/scatterlist.h>
|
|
#include <crypto/b128ops.h>
|
|
|
|
#include <net/bluetooth/bluetooth.h>
|
|
#include <net/bluetooth/hci_core.h>
|
|
#include <net/bluetooth/l2cap.h>
|
|
#include <net/bluetooth/mgmt.h>
|
|
|
|
#include "smp.h"
|
|
|
|
#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
|
|
|
|
#define SMP_TIMEOUT msecs_to_jiffies(30000)
|
|
|
|
#define AUTH_REQ_MASK 0x07
|
|
#define KEY_DIST_MASK 0x07
|
|
|
|
enum {
|
|
SMP_FLAG_TK_VALID,
|
|
SMP_FLAG_CFM_PENDING,
|
|
SMP_FLAG_MITM_AUTH,
|
|
SMP_FLAG_COMPLETE,
|
|
SMP_FLAG_INITIATOR,
|
|
};
|
|
|
|
struct smp_chan {
|
|
struct l2cap_conn *conn;
|
|
struct delayed_work security_timer;
|
|
unsigned long allow_cmd; /* Bitmask of allowed commands */
|
|
|
|
u8 preq[7]; /* SMP Pairing Request */
|
|
u8 prsp[7]; /* SMP Pairing Response */
|
|
u8 prnd[16]; /* SMP Pairing Random (local) */
|
|
u8 rrnd[16]; /* SMP Pairing Random (remote) */
|
|
u8 pcnf[16]; /* SMP Pairing Confirm */
|
|
u8 tk[16]; /* SMP Temporary Key */
|
|
u8 enc_key_size;
|
|
u8 remote_key_dist;
|
|
bdaddr_t id_addr;
|
|
u8 id_addr_type;
|
|
u8 irk[16];
|
|
struct smp_csrk *csrk;
|
|
struct smp_csrk *slave_csrk;
|
|
struct smp_ltk *ltk;
|
|
struct smp_ltk *slave_ltk;
|
|
struct smp_irk *remote_irk;
|
|
unsigned long flags;
|
|
|
|
struct crypto_blkcipher *tfm_aes;
|
|
};
|
|
|
|
static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
|
|
{
|
|
size_t i;
|
|
|
|
for (i = 0; i < len; i++)
|
|
dst[len - 1 - i] = src[i];
|
|
}
|
|
|
|
static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
|
|
{
|
|
struct blkcipher_desc desc;
|
|
struct scatterlist sg;
|
|
uint8_t tmp[16], data[16];
|
|
int err;
|
|
|
|
if (tfm == NULL) {
|
|
BT_ERR("tfm %p", tfm);
|
|
return -EINVAL;
|
|
}
|
|
|
|
desc.tfm = tfm;
|
|
desc.flags = 0;
|
|
|
|
/* The most significant octet of key corresponds to k[0] */
|
|
swap_buf(k, tmp, 16);
|
|
|
|
err = crypto_blkcipher_setkey(tfm, tmp, 16);
|
|
if (err) {
|
|
BT_ERR("cipher setkey failed: %d", err);
|
|
return err;
|
|
}
|
|
|
|
/* Most significant octet of plaintextData corresponds to data[0] */
|
|
swap_buf(r, data, 16);
|
|
|
|
sg_init_one(&sg, data, 16);
|
|
|
|
err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
|
|
if (err)
|
|
BT_ERR("Encrypt data error %d", err);
|
|
|
|
/* Most significant octet of encryptedData corresponds to data[0] */
|
|
swap_buf(data, r, 16);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int smp_ah(struct crypto_blkcipher *tfm, u8 irk[16], u8 r[3], u8 res[3])
|
|
{
|
|
u8 _res[16];
|
|
int err;
|
|
|
|
/* r' = padding || r */
|
|
memcpy(_res, r, 3);
|
|
memset(_res + 3, 0, 13);
|
|
|
|
err = smp_e(tfm, irk, _res);
|
|
if (err) {
|
|
BT_ERR("Encrypt error");
|
|
return err;
|
|
}
|
|
|
|
/* The output of the random address function ah is:
|
|
* ah(h, r) = e(k, r') mod 2^24
|
|
* The output of the security function e is then truncated to 24 bits
|
|
* by taking the least significant 24 bits of the output of e as the
|
|
* result of ah.
|
|
*/
|
|
memcpy(res, _res, 3);
|
|
|
|
return 0;
|
|
}
|
|
|
|
bool smp_irk_matches(struct hci_dev *hdev, u8 irk[16], bdaddr_t *bdaddr)
|
|
{
|
|
struct l2cap_chan *chan = hdev->smp_data;
|
|
struct crypto_blkcipher *tfm;
|
|
u8 hash[3];
|
|
int err;
|
|
|
|
if (!chan || !chan->data)
|
|
return false;
|
|
|
|
tfm = chan->data;
|
|
|
|
BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
|
|
|
|
err = smp_ah(tfm, irk, &bdaddr->b[3], hash);
|
|
if (err)
|
|
return false;
|
|
|
|
return !memcmp(bdaddr->b, hash, 3);
|
|
}
|
|
|
|
int smp_generate_rpa(struct hci_dev *hdev, u8 irk[16], bdaddr_t *rpa)
|
|
{
|
|
struct l2cap_chan *chan = hdev->smp_data;
|
|
struct crypto_blkcipher *tfm;
|
|
int err;
|
|
|
|
if (!chan || !chan->data)
|
|
return -EOPNOTSUPP;
|
|
|
|
tfm = chan->data;
|
|
|
|
get_random_bytes(&rpa->b[3], 3);
|
|
|
|
rpa->b[5] &= 0x3f; /* Clear two most significant bits */
|
|
rpa->b[5] |= 0x40; /* Set second most significant bit */
|
|
|
|
err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
BT_DBG("RPA %pMR", rpa);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_c1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r[16],
|
|
u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia, u8 _rat,
|
|
bdaddr_t *ra, u8 res[16])
|
|
{
|
|
u8 p1[16], p2[16];
|
|
int err;
|
|
|
|
memset(p1, 0, 16);
|
|
|
|
/* p1 = pres || preq || _rat || _iat */
|
|
p1[0] = _iat;
|
|
p1[1] = _rat;
|
|
memcpy(p1 + 2, preq, 7);
|
|
memcpy(p1 + 9, pres, 7);
|
|
|
|
/* p2 = padding || ia || ra */
|
|
memcpy(p2, ra, 6);
|
|
memcpy(p2 + 6, ia, 6);
|
|
memset(p2 + 12, 0, 4);
|
|
|
|
/* res = r XOR p1 */
|
|
u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
|
|
|
|
/* res = e(k, res) */
|
|
err = smp_e(tfm_aes, k, res);
|
|
if (err) {
|
|
BT_ERR("Encrypt data error");
|
|
return err;
|
|
}
|
|
|
|
/* res = res XOR p2 */
|
|
u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
|
|
|
|
/* res = e(k, res) */
|
|
err = smp_e(tfm_aes, k, res);
|
|
if (err)
|
|
BT_ERR("Encrypt data error");
|
|
|
|
return err;
|
|
}
|
|
|
|
static int smp_s1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r1[16],
|
|
u8 r2[16], u8 _r[16])
|
|
{
|
|
int err;
|
|
|
|
/* Just least significant octets from r1 and r2 are considered */
|
|
memcpy(_r, r2, 8);
|
|
memcpy(_r + 8, r1, 8);
|
|
|
|
err = smp_e(tfm_aes, k, _r);
|
|
if (err)
|
|
BT_ERR("Encrypt data error");
|
|
|
|
return err;
|
|
}
|
|
|
|
static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp;
|
|
struct kvec iv[2];
|
|
struct msghdr msg;
|
|
|
|
if (!chan)
|
|
return;
|
|
|
|
BT_DBG("code 0x%2.2x", code);
|
|
|
|
iv[0].iov_base = &code;
|
|
iv[0].iov_len = 1;
|
|
|
|
iv[1].iov_base = data;
|
|
iv[1].iov_len = len;
|
|
|
|
memset(&msg, 0, sizeof(msg));
|
|
|
|
msg.msg_iov = (struct iovec *) &iv;
|
|
msg.msg_iovlen = 2;
|
|
|
|
l2cap_chan_send(chan, &msg, 1 + len);
|
|
|
|
if (!chan->data)
|
|
return;
|
|
|
|
smp = chan->data;
|
|
|
|
cancel_delayed_work_sync(&smp->security_timer);
|
|
schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
|
|
}
|
|
|
|
static __u8 authreq_to_seclevel(__u8 authreq)
|
|
{
|
|
if (authreq & SMP_AUTH_MITM)
|
|
return BT_SECURITY_HIGH;
|
|
else
|
|
return BT_SECURITY_MEDIUM;
|
|
}
|
|
|
|
static __u8 seclevel_to_authreq(__u8 sec_level)
|
|
{
|
|
switch (sec_level) {
|
|
case BT_SECURITY_HIGH:
|
|
return SMP_AUTH_MITM | SMP_AUTH_BONDING;
|
|
case BT_SECURITY_MEDIUM:
|
|
return SMP_AUTH_BONDING;
|
|
default:
|
|
return SMP_AUTH_NONE;
|
|
}
|
|
}
|
|
|
|
static void build_pairing_cmd(struct l2cap_conn *conn,
|
|
struct smp_cmd_pairing *req,
|
|
struct smp_cmd_pairing *rsp, __u8 authreq)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct hci_dev *hdev = hcon->hdev;
|
|
u8 local_dist = 0, remote_dist = 0;
|
|
|
|
if (test_bit(HCI_BONDABLE, &conn->hcon->hdev->dev_flags)) {
|
|
local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
|
|
remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
|
|
authreq |= SMP_AUTH_BONDING;
|
|
} else {
|
|
authreq &= ~SMP_AUTH_BONDING;
|
|
}
|
|
|
|
if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags))
|
|
remote_dist |= SMP_DIST_ID_KEY;
|
|
|
|
if (test_bit(HCI_PRIVACY, &hdev->dev_flags))
|
|
local_dist |= SMP_DIST_ID_KEY;
|
|
|
|
if (rsp == NULL) {
|
|
req->io_capability = conn->hcon->io_capability;
|
|
req->oob_flag = SMP_OOB_NOT_PRESENT;
|
|
req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
|
|
req->init_key_dist = local_dist;
|
|
req->resp_key_dist = remote_dist;
|
|
req->auth_req = (authreq & AUTH_REQ_MASK);
|
|
|
|
smp->remote_key_dist = remote_dist;
|
|
return;
|
|
}
|
|
|
|
rsp->io_capability = conn->hcon->io_capability;
|
|
rsp->oob_flag = SMP_OOB_NOT_PRESENT;
|
|
rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
|
|
rsp->init_key_dist = req->init_key_dist & remote_dist;
|
|
rsp->resp_key_dist = req->resp_key_dist & local_dist;
|
|
rsp->auth_req = (authreq & AUTH_REQ_MASK);
|
|
|
|
smp->remote_key_dist = rsp->init_key_dist;
|
|
}
|
|
|
|
static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
|
|
if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) ||
|
|
(max_key_size < SMP_MIN_ENC_KEY_SIZE))
|
|
return SMP_ENC_KEY_SIZE;
|
|
|
|
smp->enc_key_size = max_key_size;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void smp_chan_destroy(struct l2cap_conn *conn)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
bool complete;
|
|
|
|
BUG_ON(!smp);
|
|
|
|
cancel_delayed_work_sync(&smp->security_timer);
|
|
|
|
complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
|
|
mgmt_smp_complete(conn->hcon, complete);
|
|
|
|
kfree(smp->csrk);
|
|
kfree(smp->slave_csrk);
|
|
|
|
crypto_free_blkcipher(smp->tfm_aes);
|
|
|
|
/* If pairing failed clean up any keys we might have */
|
|
if (!complete) {
|
|
if (smp->ltk) {
|
|
list_del_rcu(&smp->ltk->list);
|
|
kfree_rcu(smp->ltk, rcu);
|
|
}
|
|
|
|
if (smp->slave_ltk) {
|
|
list_del_rcu(&smp->slave_ltk->list);
|
|
kfree_rcu(smp->slave_ltk, rcu);
|
|
}
|
|
|
|
if (smp->remote_irk) {
|
|
list_del_rcu(&smp->remote_irk->list);
|
|
kfree_rcu(smp->remote_irk, rcu);
|
|
}
|
|
}
|
|
|
|
chan->data = NULL;
|
|
kfree(smp);
|
|
hci_conn_drop(conn->hcon);
|
|
}
|
|
|
|
static void smp_failure(struct l2cap_conn *conn, u8 reason)
|
|
{
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
|
|
if (reason)
|
|
smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
|
|
&reason);
|
|
|
|
clear_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags);
|
|
mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
|
|
|
|
if (chan->data)
|
|
smp_chan_destroy(conn);
|
|
}
|
|
|
|
#define JUST_WORKS 0x00
|
|
#define JUST_CFM 0x01
|
|
#define REQ_PASSKEY 0x02
|
|
#define CFM_PASSKEY 0x03
|
|
#define REQ_OOB 0x04
|
|
#define OVERLAP 0xFF
|
|
|
|
static const u8 gen_method[5][5] = {
|
|
{ JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
|
|
{ JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
|
|
{ CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
|
|
{ JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
|
|
{ CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
|
|
};
|
|
|
|
static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
|
|
{
|
|
/* If either side has unknown io_caps, use JUST_CFM (which gets
|
|
* converted later to JUST_WORKS if we're initiators.
|
|
*/
|
|
if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
|
|
remote_io > SMP_IO_KEYBOARD_DISPLAY)
|
|
return JUST_CFM;
|
|
|
|
return gen_method[remote_io][local_io];
|
|
}
|
|
|
|
static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
|
|
u8 local_io, u8 remote_io)
|
|
{
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
u8 method;
|
|
u32 passkey = 0;
|
|
int ret = 0;
|
|
|
|
/* Initialize key for JUST WORKS */
|
|
memset(smp->tk, 0, sizeof(smp->tk));
|
|
clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
|
|
|
|
BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
|
|
|
|
/* If neither side wants MITM, either "just" confirm an incoming
|
|
* request or use just-works for outgoing ones. The JUST_CFM
|
|
* will be converted to JUST_WORKS if necessary later in this
|
|
* function. If either side has MITM look up the method from the
|
|
* table.
|
|
*/
|
|
if (!(auth & SMP_AUTH_MITM))
|
|
method = JUST_CFM;
|
|
else
|
|
method = get_auth_method(smp, local_io, remote_io);
|
|
|
|
/* Don't confirm locally initiated pairing attempts */
|
|
if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
|
|
method = JUST_WORKS;
|
|
|
|
/* Don't bother user space with no IO capabilities */
|
|
if (method == JUST_CFM && hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
|
|
method = JUST_WORKS;
|
|
|
|
/* If Just Works, Continue with Zero TK */
|
|
if (method == JUST_WORKS) {
|
|
set_bit(SMP_FLAG_TK_VALID, &smp->flags);
|
|
return 0;
|
|
}
|
|
|
|
/* Not Just Works/Confirm results in MITM Authentication */
|
|
if (method != JUST_CFM) {
|
|
set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
|
|
if (hcon->pending_sec_level < BT_SECURITY_HIGH)
|
|
hcon->pending_sec_level = BT_SECURITY_HIGH;
|
|
}
|
|
|
|
/* If both devices have Keyoard-Display I/O, the master
|
|
* Confirms and the slave Enters the passkey.
|
|
*/
|
|
if (method == OVERLAP) {
|
|
if (hcon->role == HCI_ROLE_MASTER)
|
|
method = CFM_PASSKEY;
|
|
else
|
|
method = REQ_PASSKEY;
|
|
}
|
|
|
|
/* Generate random passkey. */
|
|
if (method == CFM_PASSKEY) {
|
|
memset(smp->tk, 0, sizeof(smp->tk));
|
|
get_random_bytes(&passkey, sizeof(passkey));
|
|
passkey %= 1000000;
|
|
put_unaligned_le32(passkey, smp->tk);
|
|
BT_DBG("PassKey: %d", passkey);
|
|
set_bit(SMP_FLAG_TK_VALID, &smp->flags);
|
|
}
|
|
|
|
if (method == REQ_PASSKEY)
|
|
ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
|
|
hcon->type, hcon->dst_type);
|
|
else if (method == JUST_CFM)
|
|
ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
|
|
hcon->type, hcon->dst_type,
|
|
passkey, 1);
|
|
else
|
|
ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
|
|
hcon->type, hcon->dst_type,
|
|
passkey, 0);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static u8 smp_confirm(struct smp_chan *smp)
|
|
{
|
|
struct l2cap_conn *conn = smp->conn;
|
|
struct smp_cmd_pairing_confirm cp;
|
|
int ret;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
|
|
conn->hcon->init_addr_type, &conn->hcon->init_addr,
|
|
conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
|
|
cp.confirm_val);
|
|
if (ret)
|
|
return SMP_UNSPECIFIED;
|
|
|
|
clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
|
|
|
|
smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
|
|
|
|
if (conn->hcon->out)
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
|
|
else
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static u8 smp_random(struct smp_chan *smp)
|
|
{
|
|
struct l2cap_conn *conn = smp->conn;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
u8 confirm[16];
|
|
int ret;
|
|
|
|
if (IS_ERR_OR_NULL(smp->tfm_aes))
|
|
return SMP_UNSPECIFIED;
|
|
|
|
BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
|
|
|
|
ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
|
|
hcon->init_addr_type, &hcon->init_addr,
|
|
hcon->resp_addr_type, &hcon->resp_addr, confirm);
|
|
if (ret)
|
|
return SMP_UNSPECIFIED;
|
|
|
|
if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
|
|
BT_ERR("Pairing failed (confirmation values mismatch)");
|
|
return SMP_CONFIRM_FAILED;
|
|
}
|
|
|
|
if (hcon->out) {
|
|
u8 stk[16];
|
|
__le64 rand = 0;
|
|
__le16 ediv = 0;
|
|
|
|
smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
|
|
|
|
memset(stk + smp->enc_key_size, 0,
|
|
SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
|
|
|
|
if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
|
|
return SMP_UNSPECIFIED;
|
|
|
|
hci_le_start_enc(hcon, ediv, rand, stk);
|
|
hcon->enc_key_size = smp->enc_key_size;
|
|
set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
|
|
} else {
|
|
u8 stk[16], auth;
|
|
__le64 rand = 0;
|
|
__le16 ediv = 0;
|
|
|
|
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
|
|
smp->prnd);
|
|
|
|
smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
|
|
|
|
memset(stk + smp->enc_key_size, 0,
|
|
SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
|
|
|
|
if (hcon->pending_sec_level == BT_SECURITY_HIGH)
|
|
auth = 1;
|
|
else
|
|
auth = 0;
|
|
|
|
/* Even though there's no _SLAVE suffix this is the
|
|
* slave STK we're adding for later lookup (the master
|
|
* STK never needs to be stored).
|
|
*/
|
|
hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
|
|
SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void smp_notify_keys(struct l2cap_conn *conn)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct hci_dev *hdev = hcon->hdev;
|
|
struct smp_cmd_pairing *req = (void *) &smp->preq[1];
|
|
struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
|
|
bool persistent;
|
|
|
|
if (smp->remote_irk) {
|
|
mgmt_new_irk(hdev, smp->remote_irk);
|
|
/* Now that user space can be considered to know the
|
|
* identity address track the connection based on it
|
|
* from now on.
|
|
*/
|
|
bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
|
|
hcon->dst_type = smp->remote_irk->addr_type;
|
|
queue_work(hdev->workqueue, &conn->id_addr_update_work);
|
|
|
|
/* When receiving an indentity resolving key for
|
|
* a remote device that does not use a resolvable
|
|
* private address, just remove the key so that
|
|
* it is possible to use the controller white
|
|
* list for scanning.
|
|
*
|
|
* Userspace will have been told to not store
|
|
* this key at this point. So it is safe to
|
|
* just remove it.
|
|
*/
|
|
if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) {
|
|
list_del_rcu(&smp->remote_irk->list);
|
|
kfree_rcu(smp->remote_irk, rcu);
|
|
smp->remote_irk = NULL;
|
|
}
|
|
}
|
|
|
|
/* The LTKs and CSRKs should be persistent only if both sides
|
|
* had the bonding bit set in their authentication requests.
|
|
*/
|
|
persistent = !!((req->auth_req & rsp->auth_req) & SMP_AUTH_BONDING);
|
|
|
|
if (smp->csrk) {
|
|
smp->csrk->bdaddr_type = hcon->dst_type;
|
|
bacpy(&smp->csrk->bdaddr, &hcon->dst);
|
|
mgmt_new_csrk(hdev, smp->csrk, persistent);
|
|
}
|
|
|
|
if (smp->slave_csrk) {
|
|
smp->slave_csrk->bdaddr_type = hcon->dst_type;
|
|
bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
|
|
mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
|
|
}
|
|
|
|
if (smp->ltk) {
|
|
smp->ltk->bdaddr_type = hcon->dst_type;
|
|
bacpy(&smp->ltk->bdaddr, &hcon->dst);
|
|
mgmt_new_ltk(hdev, smp->ltk, persistent);
|
|
}
|
|
|
|
if (smp->slave_ltk) {
|
|
smp->slave_ltk->bdaddr_type = hcon->dst_type;
|
|
bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
|
|
mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
|
|
}
|
|
}
|
|
|
|
static void smp_allow_key_dist(struct smp_chan *smp)
|
|
{
|
|
/* Allow the first expected phase 3 PDU. The rest of the PDUs
|
|
* will be allowed in each PDU handler to ensure we receive
|
|
* them in the correct order.
|
|
*/
|
|
if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
|
|
else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
|
|
else if (smp->remote_key_dist & SMP_DIST_SIGN)
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
|
|
}
|
|
|
|
static void smp_distribute_keys(struct smp_chan *smp)
|
|
{
|
|
struct smp_cmd_pairing *req, *rsp;
|
|
struct l2cap_conn *conn = smp->conn;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct hci_dev *hdev = hcon->hdev;
|
|
__u8 *keydist;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
rsp = (void *) &smp->prsp[1];
|
|
|
|
/* The responder sends its keys first */
|
|
if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
|
|
smp_allow_key_dist(smp);
|
|
return;
|
|
}
|
|
|
|
req = (void *) &smp->preq[1];
|
|
|
|
if (hcon->out) {
|
|
keydist = &rsp->init_key_dist;
|
|
*keydist &= req->init_key_dist;
|
|
} else {
|
|
keydist = &rsp->resp_key_dist;
|
|
*keydist &= req->resp_key_dist;
|
|
}
|
|
|
|
BT_DBG("keydist 0x%x", *keydist);
|
|
|
|
if (*keydist & SMP_DIST_ENC_KEY) {
|
|
struct smp_cmd_encrypt_info enc;
|
|
struct smp_cmd_master_ident ident;
|
|
struct smp_ltk *ltk;
|
|
u8 authenticated;
|
|
__le16 ediv;
|
|
__le64 rand;
|
|
|
|
get_random_bytes(enc.ltk, sizeof(enc.ltk));
|
|
get_random_bytes(&ediv, sizeof(ediv));
|
|
get_random_bytes(&rand, sizeof(rand));
|
|
|
|
smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
|
|
|
|
authenticated = hcon->sec_level == BT_SECURITY_HIGH;
|
|
ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
|
|
SMP_LTK_SLAVE, authenticated, enc.ltk,
|
|
smp->enc_key_size, ediv, rand);
|
|
smp->slave_ltk = ltk;
|
|
|
|
ident.ediv = ediv;
|
|
ident.rand = rand;
|
|
|
|
smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
|
|
|
|
*keydist &= ~SMP_DIST_ENC_KEY;
|
|
}
|
|
|
|
if (*keydist & SMP_DIST_ID_KEY) {
|
|
struct smp_cmd_ident_addr_info addrinfo;
|
|
struct smp_cmd_ident_info idinfo;
|
|
|
|
memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
|
|
|
|
smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
|
|
|
|
/* The hci_conn contains the local identity address
|
|
* after the connection has been established.
|
|
*
|
|
* This is true even when the connection has been
|
|
* established using a resolvable random address.
|
|
*/
|
|
bacpy(&addrinfo.bdaddr, &hcon->src);
|
|
addrinfo.addr_type = hcon->src_type;
|
|
|
|
smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
|
|
&addrinfo);
|
|
|
|
*keydist &= ~SMP_DIST_ID_KEY;
|
|
}
|
|
|
|
if (*keydist & SMP_DIST_SIGN) {
|
|
struct smp_cmd_sign_info sign;
|
|
struct smp_csrk *csrk;
|
|
|
|
/* Generate a new random key */
|
|
get_random_bytes(sign.csrk, sizeof(sign.csrk));
|
|
|
|
csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
|
|
if (csrk) {
|
|
csrk->master = 0x00;
|
|
memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
|
|
}
|
|
smp->slave_csrk = csrk;
|
|
|
|
smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
|
|
|
|
*keydist &= ~SMP_DIST_SIGN;
|
|
}
|
|
|
|
/* If there are still keys to be received wait for them */
|
|
if (smp->remote_key_dist & KEY_DIST_MASK) {
|
|
smp_allow_key_dist(smp);
|
|
return;
|
|
}
|
|
|
|
set_bit(SMP_FLAG_COMPLETE, &smp->flags);
|
|
smp_notify_keys(conn);
|
|
|
|
smp_chan_destroy(conn);
|
|
}
|
|
|
|
static void smp_timeout(struct work_struct *work)
|
|
{
|
|
struct smp_chan *smp = container_of(work, struct smp_chan,
|
|
security_timer.work);
|
|
struct l2cap_conn *conn = smp->conn;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
|
|
}
|
|
|
|
static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp;
|
|
|
|
smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
|
|
if (!smp)
|
|
return NULL;
|
|
|
|
smp->tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
|
|
if (IS_ERR(smp->tfm_aes)) {
|
|
BT_ERR("Unable to create ECB crypto context");
|
|
kfree(smp);
|
|
return NULL;
|
|
}
|
|
|
|
smp->conn = conn;
|
|
chan->data = smp;
|
|
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
|
|
|
|
INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
|
|
|
|
hci_conn_hold(conn->hcon);
|
|
|
|
return smp;
|
|
}
|
|
|
|
int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
|
|
{
|
|
struct l2cap_conn *conn = hcon->l2cap_data;
|
|
struct l2cap_chan *chan;
|
|
struct smp_chan *smp;
|
|
u32 value;
|
|
int err;
|
|
|
|
BT_DBG("");
|
|
|
|
if (!conn)
|
|
return -ENOTCONN;
|
|
|
|
chan = conn->smp;
|
|
if (!chan)
|
|
return -ENOTCONN;
|
|
|
|
l2cap_chan_lock(chan);
|
|
if (!chan->data) {
|
|
err = -ENOTCONN;
|
|
goto unlock;
|
|
}
|
|
|
|
smp = chan->data;
|
|
|
|
switch (mgmt_op) {
|
|
case MGMT_OP_USER_PASSKEY_REPLY:
|
|
value = le32_to_cpu(passkey);
|
|
memset(smp->tk, 0, sizeof(smp->tk));
|
|
BT_DBG("PassKey: %d", value);
|
|
put_unaligned_le32(value, smp->tk);
|
|
/* Fall Through */
|
|
case MGMT_OP_USER_CONFIRM_REPLY:
|
|
set_bit(SMP_FLAG_TK_VALID, &smp->flags);
|
|
break;
|
|
case MGMT_OP_USER_PASSKEY_NEG_REPLY:
|
|
case MGMT_OP_USER_CONFIRM_NEG_REPLY:
|
|
smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
|
|
err = 0;
|
|
goto unlock;
|
|
default:
|
|
smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
|
|
err = -EOPNOTSUPP;
|
|
goto unlock;
|
|
}
|
|
|
|
err = 0;
|
|
|
|
/* If it is our turn to send Pairing Confirm, do so now */
|
|
if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
|
|
u8 rsp = smp_confirm(smp);
|
|
if (rsp)
|
|
smp_failure(conn, rsp);
|
|
}
|
|
|
|
unlock:
|
|
l2cap_chan_unlock(chan);
|
|
return err;
|
|
}
|
|
|
|
static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_pairing rsp, *req = (void *) skb->data;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct hci_dev *hdev = conn->hcon->hdev;
|
|
struct smp_chan *smp;
|
|
u8 key_size, auth, sec_level;
|
|
int ret;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
if (skb->len < sizeof(*req))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
if (conn->hcon->role != HCI_ROLE_SLAVE)
|
|
return SMP_CMD_NOTSUPP;
|
|
|
|
if (!chan->data)
|
|
smp = smp_chan_create(conn);
|
|
else
|
|
smp = chan->data;
|
|
|
|
if (!smp)
|
|
return SMP_UNSPECIFIED;
|
|
|
|
/* We didn't start the pairing, so match remote */
|
|
auth = req->auth_req & AUTH_REQ_MASK;
|
|
|
|
if (!test_bit(HCI_BONDABLE, &hdev->dev_flags) &&
|
|
(auth & SMP_AUTH_BONDING))
|
|
return SMP_PAIRING_NOTSUPP;
|
|
|
|
smp->preq[0] = SMP_CMD_PAIRING_REQ;
|
|
memcpy(&smp->preq[1], req, sizeof(*req));
|
|
skb_pull(skb, sizeof(*req));
|
|
|
|
if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
|
|
sec_level = BT_SECURITY_MEDIUM;
|
|
else
|
|
sec_level = authreq_to_seclevel(auth);
|
|
|
|
if (sec_level > conn->hcon->pending_sec_level)
|
|
conn->hcon->pending_sec_level = sec_level;
|
|
|
|
/* If we need MITM check that it can be achieved */
|
|
if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
|
|
u8 method;
|
|
|
|
method = get_auth_method(smp, conn->hcon->io_capability,
|
|
req->io_capability);
|
|
if (method == JUST_WORKS || method == JUST_CFM)
|
|
return SMP_AUTH_REQUIREMENTS;
|
|
}
|
|
|
|
build_pairing_cmd(conn, req, &rsp, auth);
|
|
|
|
key_size = min(req->max_key_size, rsp.max_key_size);
|
|
if (check_enc_key_size(conn, key_size))
|
|
return SMP_ENC_KEY_SIZE;
|
|
|
|
get_random_bytes(smp->prnd, sizeof(smp->prnd));
|
|
|
|
smp->prsp[0] = SMP_CMD_PAIRING_RSP;
|
|
memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
|
|
|
|
smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
|
|
|
|
/* Request setup of TK */
|
|
ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
|
|
if (ret)
|
|
return SMP_UNSPECIFIED;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
u8 key_size, auth;
|
|
int ret;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
if (skb->len < sizeof(*rsp))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
if (conn->hcon->role != HCI_ROLE_MASTER)
|
|
return SMP_CMD_NOTSUPP;
|
|
|
|
skb_pull(skb, sizeof(*rsp));
|
|
|
|
req = (void *) &smp->preq[1];
|
|
|
|
key_size = min(req->max_key_size, rsp->max_key_size);
|
|
if (check_enc_key_size(conn, key_size))
|
|
return SMP_ENC_KEY_SIZE;
|
|
|
|
auth = rsp->auth_req & AUTH_REQ_MASK;
|
|
|
|
/* If we need MITM check that it can be achieved */
|
|
if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
|
|
u8 method;
|
|
|
|
method = get_auth_method(smp, req->io_capability,
|
|
rsp->io_capability);
|
|
if (method == JUST_WORKS || method == JUST_CFM)
|
|
return SMP_AUTH_REQUIREMENTS;
|
|
}
|
|
|
|
get_random_bytes(smp->prnd, sizeof(smp->prnd));
|
|
|
|
smp->prsp[0] = SMP_CMD_PAIRING_RSP;
|
|
memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
|
|
|
|
/* Update remote key distribution in case the remote cleared
|
|
* some bits that we had enabled in our request.
|
|
*/
|
|
smp->remote_key_dist &= rsp->resp_key_dist;
|
|
|
|
auth |= req->auth_req;
|
|
|
|
ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
|
|
if (ret)
|
|
return SMP_UNSPECIFIED;
|
|
|
|
set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
|
|
|
|
/* Can't compose response until we have been confirmed */
|
|
if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
|
|
return smp_confirm(smp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
|
|
BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
|
|
|
|
if (skb->len < sizeof(smp->pcnf))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
|
|
skb_pull(skb, sizeof(smp->pcnf));
|
|
|
|
if (conn->hcon->out) {
|
|
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
|
|
smp->prnd);
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
|
|
return 0;
|
|
}
|
|
|
|
if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
|
|
return smp_confirm(smp);
|
|
else
|
|
set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
if (skb->len < sizeof(smp->rrnd))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
|
|
skb_pull(skb, sizeof(smp->rrnd));
|
|
|
|
return smp_random(smp);
|
|
}
|
|
|
|
static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
|
|
{
|
|
struct smp_ltk *key;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
|
|
key = hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type,
|
|
hcon->role);
|
|
if (!key)
|
|
return false;
|
|
|
|
if (smp_ltk_sec_level(key) < sec_level)
|
|
return false;
|
|
|
|
if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
|
|
return true;
|
|
|
|
hci_le_start_enc(hcon, key->ediv, key->rand, key->val);
|
|
hcon->enc_key_size = key->enc_size;
|
|
|
|
/* We never store STKs for master role, so clear this flag */
|
|
clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
|
|
enum smp_key_pref key_pref)
|
|
{
|
|
if (sec_level == BT_SECURITY_LOW)
|
|
return true;
|
|
|
|
/* If we're encrypted with an STK but the caller prefers using
|
|
* LTK claim insufficient security. This way we allow the
|
|
* connection to be re-encrypted with an LTK, even if the LTK
|
|
* provides the same level of security. Only exception is if we
|
|
* don't have an LTK (e.g. because of key distribution bits).
|
|
*/
|
|
if (key_pref == SMP_USE_LTK &&
|
|
test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
|
|
hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type,
|
|
hcon->role))
|
|
return false;
|
|
|
|
if (hcon->sec_level >= sec_level)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_security_req *rp = (void *) skb->data;
|
|
struct smp_cmd_pairing cp;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct smp_chan *smp;
|
|
u8 sec_level, auth;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
if (skb->len < sizeof(*rp))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
if (hcon->role != HCI_ROLE_MASTER)
|
|
return SMP_CMD_NOTSUPP;
|
|
|
|
auth = rp->auth_req & AUTH_REQ_MASK;
|
|
|
|
if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
|
|
sec_level = BT_SECURITY_MEDIUM;
|
|
else
|
|
sec_level = authreq_to_seclevel(auth);
|
|
|
|
if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
|
|
return 0;
|
|
|
|
if (sec_level > hcon->pending_sec_level)
|
|
hcon->pending_sec_level = sec_level;
|
|
|
|
if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
|
|
return 0;
|
|
|
|
smp = smp_chan_create(conn);
|
|
if (!smp)
|
|
return SMP_UNSPECIFIED;
|
|
|
|
if (!test_bit(HCI_BONDABLE, &hcon->hdev->dev_flags) &&
|
|
(auth & SMP_AUTH_BONDING))
|
|
return SMP_PAIRING_NOTSUPP;
|
|
|
|
skb_pull(skb, sizeof(*rp));
|
|
|
|
memset(&cp, 0, sizeof(cp));
|
|
build_pairing_cmd(conn, &cp, NULL, auth);
|
|
|
|
smp->preq[0] = SMP_CMD_PAIRING_REQ;
|
|
memcpy(&smp->preq[1], &cp, sizeof(cp));
|
|
|
|
smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
|
|
{
|
|
struct l2cap_conn *conn = hcon->l2cap_data;
|
|
struct l2cap_chan *chan;
|
|
struct smp_chan *smp;
|
|
__u8 authreq;
|
|
int ret;
|
|
|
|
BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
|
|
|
|
/* This may be NULL if there's an unexpected disconnection */
|
|
if (!conn)
|
|
return 1;
|
|
|
|
chan = conn->smp;
|
|
|
|
if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags))
|
|
return 1;
|
|
|
|
if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
|
|
return 1;
|
|
|
|
if (sec_level > hcon->pending_sec_level)
|
|
hcon->pending_sec_level = sec_level;
|
|
|
|
if (hcon->role == HCI_ROLE_MASTER)
|
|
if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
|
|
return 0;
|
|
|
|
l2cap_chan_lock(chan);
|
|
|
|
/* If SMP is already in progress ignore this request */
|
|
if (chan->data) {
|
|
ret = 0;
|
|
goto unlock;
|
|
}
|
|
|
|
smp = smp_chan_create(conn);
|
|
if (!smp) {
|
|
ret = 1;
|
|
goto unlock;
|
|
}
|
|
|
|
authreq = seclevel_to_authreq(sec_level);
|
|
|
|
/* Require MITM if IO Capability allows or the security level
|
|
* requires it.
|
|
*/
|
|
if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
|
|
hcon->pending_sec_level > BT_SECURITY_MEDIUM)
|
|
authreq |= SMP_AUTH_MITM;
|
|
|
|
if (hcon->role == HCI_ROLE_MASTER) {
|
|
struct smp_cmd_pairing cp;
|
|
|
|
build_pairing_cmd(conn, &cp, NULL, authreq);
|
|
smp->preq[0] = SMP_CMD_PAIRING_REQ;
|
|
memcpy(&smp->preq[1], &cp, sizeof(cp));
|
|
|
|
smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
|
|
} else {
|
|
struct smp_cmd_security_req cp;
|
|
cp.auth_req = authreq;
|
|
smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
|
|
}
|
|
|
|
set_bit(SMP_FLAG_INITIATOR, &smp->flags);
|
|
ret = 0;
|
|
|
|
unlock:
|
|
l2cap_chan_unlock(chan);
|
|
return ret;
|
|
}
|
|
|
|
static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_encrypt_info *rp = (void *) skb->data;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
if (skb->len < sizeof(*rp))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
|
|
|
|
skb_pull(skb, sizeof(*rp));
|
|
|
|
memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_master_ident *rp = (void *) skb->data;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
struct hci_dev *hdev = conn->hcon->hdev;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct smp_ltk *ltk;
|
|
u8 authenticated;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
if (skb->len < sizeof(*rp))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
/* Mark the information as received */
|
|
smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
|
|
|
|
if (smp->remote_key_dist & SMP_DIST_ID_KEY)
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
|
|
else if (smp->remote_key_dist & SMP_DIST_SIGN)
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
|
|
|
|
skb_pull(skb, sizeof(*rp));
|
|
|
|
authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
|
|
ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
|
|
authenticated, smp->tk, smp->enc_key_size,
|
|
rp->ediv, rp->rand);
|
|
smp->ltk = ltk;
|
|
if (!(smp->remote_key_dist & KEY_DIST_MASK))
|
|
smp_distribute_keys(smp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_ident_info *info = (void *) skb->data;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
|
|
BT_DBG("");
|
|
|
|
if (skb->len < sizeof(*info))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
|
|
|
|
skb_pull(skb, sizeof(*info));
|
|
|
|
memcpy(smp->irk, info->irk, 16);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_ident_addr_info *info = (void *) skb->data;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
bdaddr_t rpa;
|
|
|
|
BT_DBG("");
|
|
|
|
if (skb->len < sizeof(*info))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
/* Mark the information as received */
|
|
smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
|
|
|
|
if (smp->remote_key_dist & SMP_DIST_SIGN)
|
|
SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
|
|
|
|
skb_pull(skb, sizeof(*info));
|
|
|
|
/* Strictly speaking the Core Specification (4.1) allows sending
|
|
* an empty address which would force us to rely on just the IRK
|
|
* as "identity information". However, since such
|
|
* implementations are not known of and in order to not over
|
|
* complicate our implementation, simply pretend that we never
|
|
* received an IRK for such a device.
|
|
*/
|
|
if (!bacmp(&info->bdaddr, BDADDR_ANY)) {
|
|
BT_ERR("Ignoring IRK with no identity address");
|
|
goto distribute;
|
|
}
|
|
|
|
bacpy(&smp->id_addr, &info->bdaddr);
|
|
smp->id_addr_type = info->addr_type;
|
|
|
|
if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
|
|
bacpy(&rpa, &hcon->dst);
|
|
else
|
|
bacpy(&rpa, BDADDR_ANY);
|
|
|
|
smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
|
|
smp->id_addr_type, smp->irk, &rpa);
|
|
|
|
distribute:
|
|
if (!(smp->remote_key_dist & KEY_DIST_MASK))
|
|
smp_distribute_keys(smp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
|
|
{
|
|
struct smp_cmd_sign_info *rp = (void *) skb->data;
|
|
struct l2cap_chan *chan = conn->smp;
|
|
struct smp_chan *smp = chan->data;
|
|
struct smp_csrk *csrk;
|
|
|
|
BT_DBG("conn %p", conn);
|
|
|
|
if (skb->len < sizeof(*rp))
|
|
return SMP_INVALID_PARAMS;
|
|
|
|
/* Mark the information as received */
|
|
smp->remote_key_dist &= ~SMP_DIST_SIGN;
|
|
|
|
skb_pull(skb, sizeof(*rp));
|
|
|
|
csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
|
|
if (csrk) {
|
|
csrk->master = 0x01;
|
|
memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
|
|
}
|
|
smp->csrk = csrk;
|
|
smp_distribute_keys(smp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
|
|
{
|
|
struct l2cap_conn *conn = chan->conn;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
struct smp_chan *smp;
|
|
__u8 code, reason;
|
|
int err = 0;
|
|
|
|
if (hcon->type != LE_LINK) {
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
if (skb->len < 1)
|
|
return -EILSEQ;
|
|
|
|
if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) {
|
|
reason = SMP_PAIRING_NOTSUPP;
|
|
goto done;
|
|
}
|
|
|
|
code = skb->data[0];
|
|
skb_pull(skb, sizeof(code));
|
|
|
|
smp = chan->data;
|
|
|
|
if (code > SMP_CMD_MAX)
|
|
goto drop;
|
|
|
|
if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
|
|
goto drop;
|
|
|
|
/* If we don't have a context the only allowed commands are
|
|
* pairing request and security request.
|
|
*/
|
|
if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
|
|
goto drop;
|
|
|
|
switch (code) {
|
|
case SMP_CMD_PAIRING_REQ:
|
|
reason = smp_cmd_pairing_req(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_PAIRING_FAIL:
|
|
smp_failure(conn, 0);
|
|
err = -EPERM;
|
|
break;
|
|
|
|
case SMP_CMD_PAIRING_RSP:
|
|
reason = smp_cmd_pairing_rsp(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_SECURITY_REQ:
|
|
reason = smp_cmd_security_req(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_PAIRING_CONFIRM:
|
|
reason = smp_cmd_pairing_confirm(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_PAIRING_RANDOM:
|
|
reason = smp_cmd_pairing_random(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_ENCRYPT_INFO:
|
|
reason = smp_cmd_encrypt_info(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_MASTER_IDENT:
|
|
reason = smp_cmd_master_ident(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_IDENT_INFO:
|
|
reason = smp_cmd_ident_info(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_IDENT_ADDR_INFO:
|
|
reason = smp_cmd_ident_addr_info(conn, skb);
|
|
break;
|
|
|
|
case SMP_CMD_SIGN_INFO:
|
|
reason = smp_cmd_sign_info(conn, skb);
|
|
break;
|
|
|
|
default:
|
|
BT_DBG("Unknown command code 0x%2.2x", code);
|
|
reason = SMP_CMD_NOTSUPP;
|
|
goto done;
|
|
}
|
|
|
|
done:
|
|
if (!err) {
|
|
if (reason)
|
|
smp_failure(conn, reason);
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
return err;
|
|
|
|
drop:
|
|
BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
|
|
code, &hcon->dst);
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
static void smp_teardown_cb(struct l2cap_chan *chan, int err)
|
|
{
|
|
struct l2cap_conn *conn = chan->conn;
|
|
|
|
BT_DBG("chan %p", chan);
|
|
|
|
if (chan->data)
|
|
smp_chan_destroy(conn);
|
|
|
|
conn->smp = NULL;
|
|
l2cap_chan_put(chan);
|
|
}
|
|
|
|
static void smp_resume_cb(struct l2cap_chan *chan)
|
|
{
|
|
struct smp_chan *smp = chan->data;
|
|
struct l2cap_conn *conn = chan->conn;
|
|
struct hci_conn *hcon = conn->hcon;
|
|
|
|
BT_DBG("chan %p", chan);
|
|
|
|
if (!smp)
|
|
return;
|
|
|
|
if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
|
|
return;
|
|
|
|
cancel_delayed_work(&smp->security_timer);
|
|
|
|
smp_distribute_keys(smp);
|
|
}
|
|
|
|
static void smp_ready_cb(struct l2cap_chan *chan)
|
|
{
|
|
struct l2cap_conn *conn = chan->conn;
|
|
|
|
BT_DBG("chan %p", chan);
|
|
|
|
conn->smp = chan;
|
|
l2cap_chan_hold(chan);
|
|
}
|
|
|
|
static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
|
|
{
|
|
int err;
|
|
|
|
BT_DBG("chan %p", chan);
|
|
|
|
err = smp_sig_channel(chan, skb);
|
|
if (err) {
|
|
struct smp_chan *smp = chan->data;
|
|
|
|
if (smp)
|
|
cancel_delayed_work_sync(&smp->security_timer);
|
|
|
|
hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
|
|
unsigned long hdr_len,
|
|
unsigned long len, int nb)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
|
|
if (!skb)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
skb->priority = HCI_PRIO_MAX;
|
|
bt_cb(skb)->chan = chan;
|
|
|
|
return skb;
|
|
}
|
|
|
|
static const struct l2cap_ops smp_chan_ops = {
|
|
.name = "Security Manager",
|
|
.ready = smp_ready_cb,
|
|
.recv = smp_recv_cb,
|
|
.alloc_skb = smp_alloc_skb_cb,
|
|
.teardown = smp_teardown_cb,
|
|
.resume = smp_resume_cb,
|
|
|
|
.new_connection = l2cap_chan_no_new_connection,
|
|
.state_change = l2cap_chan_no_state_change,
|
|
.close = l2cap_chan_no_close,
|
|
.defer = l2cap_chan_no_defer,
|
|
.suspend = l2cap_chan_no_suspend,
|
|
.set_shutdown = l2cap_chan_no_set_shutdown,
|
|
.get_sndtimeo = l2cap_chan_no_get_sndtimeo,
|
|
.memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec,
|
|
};
|
|
|
|
static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
|
|
{
|
|
struct l2cap_chan *chan;
|
|
|
|
BT_DBG("pchan %p", pchan);
|
|
|
|
chan = l2cap_chan_create();
|
|
if (!chan)
|
|
return NULL;
|
|
|
|
chan->chan_type = pchan->chan_type;
|
|
chan->ops = &smp_chan_ops;
|
|
chan->scid = pchan->scid;
|
|
chan->dcid = chan->scid;
|
|
chan->imtu = pchan->imtu;
|
|
chan->omtu = pchan->omtu;
|
|
chan->mode = pchan->mode;
|
|
|
|
/* Other L2CAP channels may request SMP routines in order to
|
|
* change the security level. This means that the SMP channel
|
|
* lock must be considered in its own category to avoid lockdep
|
|
* warnings.
|
|
*/
|
|
atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
|
|
|
|
BT_DBG("created chan %p", chan);
|
|
|
|
return chan;
|
|
}
|
|
|
|
static const struct l2cap_ops smp_root_chan_ops = {
|
|
.name = "Security Manager Root",
|
|
.new_connection = smp_new_conn_cb,
|
|
|
|
/* None of these are implemented for the root channel */
|
|
.close = l2cap_chan_no_close,
|
|
.alloc_skb = l2cap_chan_no_alloc_skb,
|
|
.recv = l2cap_chan_no_recv,
|
|
.state_change = l2cap_chan_no_state_change,
|
|
.teardown = l2cap_chan_no_teardown,
|
|
.ready = l2cap_chan_no_ready,
|
|
.defer = l2cap_chan_no_defer,
|
|
.suspend = l2cap_chan_no_suspend,
|
|
.resume = l2cap_chan_no_resume,
|
|
.set_shutdown = l2cap_chan_no_set_shutdown,
|
|
.get_sndtimeo = l2cap_chan_no_get_sndtimeo,
|
|
.memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec,
|
|
};
|
|
|
|
int smp_register(struct hci_dev *hdev)
|
|
{
|
|
struct l2cap_chan *chan;
|
|
struct crypto_blkcipher *tfm_aes;
|
|
|
|
BT_DBG("%s", hdev->name);
|
|
|
|
tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0);
|
|
if (IS_ERR(tfm_aes)) {
|
|
int err = PTR_ERR(tfm_aes);
|
|
BT_ERR("Unable to create crypto context");
|
|
return err;
|
|
}
|
|
|
|
chan = l2cap_chan_create();
|
|
if (!chan) {
|
|
crypto_free_blkcipher(tfm_aes);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
chan->data = tfm_aes;
|
|
|
|
l2cap_add_scid(chan, L2CAP_CID_SMP);
|
|
|
|
l2cap_chan_set_defaults(chan);
|
|
|
|
bacpy(&chan->src, &hdev->bdaddr);
|
|
chan->src_type = BDADDR_LE_PUBLIC;
|
|
chan->state = BT_LISTEN;
|
|
chan->mode = L2CAP_MODE_BASIC;
|
|
chan->imtu = L2CAP_DEFAULT_MTU;
|
|
chan->ops = &smp_root_chan_ops;
|
|
|
|
/* Set correct nesting level for a parent/listening channel */
|
|
atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
|
|
|
|
hdev->smp_data = chan;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void smp_unregister(struct hci_dev *hdev)
|
|
{
|
|
struct l2cap_chan *chan = hdev->smp_data;
|
|
struct crypto_blkcipher *tfm_aes;
|
|
|
|
if (!chan)
|
|
return;
|
|
|
|
BT_DBG("%s chan %p", hdev->name, chan);
|
|
|
|
tfm_aes = chan->data;
|
|
if (tfm_aes) {
|
|
chan->data = NULL;
|
|
crypto_free_blkcipher(tfm_aes);
|
|
}
|
|
|
|
hdev->smp_data = NULL;
|
|
l2cap_chan_put(chan);
|
|
}
|