/*
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/debugfs.h>
#include <linux/scatterlist.h>
#include <crypto/aes.h>
#include <crypto/hash.h>
#include <crypto/kpp.h>
#include <crypto/utils.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/l2cap.h>
#include <net/bluetooth/mgmt.h>
#include "ecdh_helper.h"
#include "smp.h"
#define SMP_DEV(hdev) \
((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data)
/* Low-level debug macros to be used for stuff that we don't want
* accidentally in dmesg , i . e . the values of the various crypto keys
* and the inputs & outputs of crypto functions .
*/
#ifdef DEBUG
#define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
## __VA_ARGS__)
#else
#define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
## __VA_ARGS__)
#endif
#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
/* Keys which are not distributed with Secure Connections */
#define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY)
#define SMP_TIMEOUT secs_to_jiffies(30 )
#define ID_ADDR_TIMEOUT msecs_to_jiffies(200 )
#define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \
0 x3f : 0 x07)
#define KEY_DIST_MASK 0 x07
/* Maximum message length that can be passed to aes_cmac */
#define CMAC_MSG_MAX 80
enum {
SMP_FLAG_TK_VALID,
SMP_FLAG_CFM_PENDING,
SMP_FLAG_MITM_AUTH,
SMP_FLAG_COMPLETE,
SMP_FLAG_INITIATOR,
SMP_FLAG_SC,
SMP_FLAG_REMOTE_PK,
SMP_FLAG_DEBUG_KEY,
SMP_FLAG_WAIT_USER,
SMP_FLAG_DHKEY_PENDING,
SMP_FLAG_REMOTE_OOB,
SMP_FLAG_LOCAL_OOB,
SMP_FLAG_CT2,
};
struct smp_dev {
/* Secure Connections OOB data */
bool local_oob;
u8 local_pk[64 ];
u8 local_rand[16 ];
bool debug_key;
struct crypto_shash *tfm_cmac;
struct crypto_kpp *tfm_ecdh;
};
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 rr[16 ]; /* Remote OOB ra/rb value */
u8 lr[16 ]; /* Local OOB ra/rb value */
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 *responder_csrk;
struct smp_ltk *ltk;
struct smp_ltk *responder_ltk;
struct smp_irk *remote_irk;
u8 *link_key;
unsigned long flags;
u8 method;
u8 passkey_round;
/* Secure Connections variables */
u8 local_pk[64 ];
u8 remote_pk[64 ];
u8 dhkey[32 ];
u8 mackey[16 ];
struct crypto_shash *tfm_cmac;
struct crypto_kpp *tfm_ecdh;
};
/* These debug key values are defined in the SMP section of the core
* specification . debug_pk is the public debug key and debug_sk the
* private debug key .
*/
static const u8 debug_pk[64 ] = {
0 xe6, 0 x9d, 0 x35, 0 x0e, 0 x48, 0 x01, 0 x03, 0 xcc,
0 xdb, 0 xfd, 0 xf4, 0 xac, 0 x11, 0 x91, 0 xf4, 0 xef,
0 xb9, 0 xa5, 0 xf9, 0 xe9, 0 xa7, 0 x83, 0 x2c, 0 x5e,
0 x2c, 0 xbe, 0 x97, 0 xf2, 0 xd2, 0 x03, 0 xb0, 0 x20,
0 x8b, 0 xd2, 0 x89, 0 x15, 0 xd0, 0 x8e, 0 x1c, 0 x74,
0 x24, 0 x30, 0 xed, 0 x8f, 0 xc2, 0 x45, 0 x63, 0 x76,
0 x5c, 0 x15, 0 x52, 0 x5a, 0 xbf, 0 x9a, 0 x32, 0 x63,
0 x6d, 0 xeb, 0 x2a, 0 x65, 0 x49, 0 x9c, 0 x80, 0 xdc,
};
static const u8 debug_sk[32 ] = {
0 xbd, 0 x1a, 0 x3c, 0 xcd, 0 xa6, 0 xb8, 0 x99, 0 x58,
0 x99, 0 xb7, 0 x40, 0 xeb, 0 x7b, 0 x60, 0 xff, 0 x4a,
0 x50, 0 x3f, 0 x10, 0 xd2, 0 xe3, 0 xb3, 0 xc9, 0 x74,
0 x38, 0 x5f, 0 xc5, 0 xa3, 0 xd4, 0 xf6, 0 x49, 0 x3f,
};
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];
}
/* The following functions map to the LE SC SMP crypto functions
* AES - CMAC , f4 , f5 , f6 , g2 and h6 .
*/
static int aes_cmac(struct crypto_shash *tfm, const u8 k[16 ], const u8 *m,
size_t len, u8 mac[16 ])
{
uint8_t tmp[16 ], mac_msb[16 ], msg_msb[CMAC_MSG_MAX];
int err;
if (len > CMAC_MSG_MAX)
return -EFBIG;
if (!tfm) {
BT_ERR("tfm %p" , tfm);
return -EINVAL;
}
/* Swap key and message from LSB to MSB */
swap_buf(k, tmp, 16 );
swap_buf(m, msg_msb, len);
SMP_DBG("msg (len %zu) %*phN" , len, (int ) len, m);
SMP_DBG("key %16phN" , k);
err = crypto_shash_setkey(tfm, tmp, 16 );
if (err) {
BT_ERR("cipher setkey failed: %d" , err);
return err;
}
err = crypto_shash_tfm_digest(tfm, msg_msb, len, mac_msb);
if (err) {
BT_ERR("Hash computation error %d" , err);
return err;
}
swap_buf(mac_msb, mac, 16 );
SMP_DBG("mac %16phN" , mac);
return 0 ;
}
static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32 ],
const u8 v[32 ], const u8 x[16 ], u8 z, u8 res[16 ])
{
u8 m[65 ];
int err;
SMP_DBG("u %32phN" , u);
SMP_DBG("v %32phN" , v);
SMP_DBG("x %16phN z %02x" , x, z);
m[0 ] = z;
memcpy(m + 1 , v, 32 );
memcpy(m + 33 , u, 32 );
err = aes_cmac(tfm_cmac, x, m, sizeof (m), res);
if (err)
return err;
SMP_DBG("res %16phN" , res);
return err;
}
static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32 ],
const u8 n1[16 ], const u8 n2[16 ], const u8 a1[7 ],
const u8 a2[7 ], u8 mackey[16 ], u8 ltk[16 ])
{
/* The btle, salt and length "magic" values are as defined in
* the SMP section of the Bluetooth core specification . In ASCII
* the btle value ends up being ' btle ' . The salt is just a
* random number whereas length is the value 256 in little
* endian format .
*/
const u8 btle[4 ] = { 0 x65, 0 x6c, 0 x74, 0 x62 };
const u8 salt[16 ] = { 0 xbe, 0 x83, 0 x60, 0 x5a, 0 xdb, 0 x0b, 0 x37, 0 x60,
0 x38, 0 xa5, 0 xf5, 0 xaa, 0 x91, 0 x83, 0 x88, 0 x6c };
const u8 length[2 ] = { 0 x00, 0 x01 };
u8 m[53 ], t[16 ];
int err;
SMP_DBG("w %32phN" , w);
SMP_DBG("n1 %16phN n2 %16phN" , n1, n2);
SMP_DBG("a1 %7phN a2 %7phN" , a1, a2);
err = aes_cmac(tfm_cmac, salt, w, 32 , t);
if (err)
return err;
SMP_DBG("t %16phN" , t);
memcpy(m, length, 2 );
memcpy(m + 2 , a2, 7 );
memcpy(m + 9 , a1, 7 );
memcpy(m + 16 , n2, 16 );
memcpy(m + 32 , n1, 16 );
memcpy(m + 48 , btle, 4 );
m[52 ] = 0 ; /* Counter */
err = aes_cmac(tfm_cmac, t, m, sizeof (m), mackey);
if (err)
return err;
SMP_DBG("mackey %16phN" , mackey);
m[52 ] = 1 ; /* Counter */
err = aes_cmac(tfm_cmac, t, m, sizeof (m), ltk);
if (err)
return err;
SMP_DBG("ltk %16phN" , ltk);
return 0 ;
}
static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16 ],
const u8 n1[16 ], const u8 n2[16 ], const u8 r[16 ],
const u8 io_cap[3 ], const u8 a1[7 ], const u8 a2[7 ],
u8 res[16 ])
{
u8 m[65 ];
int err;
SMP_DBG("w %16phN" , w);
SMP_DBG("n1 %16phN n2 %16phN" , n1, n2);
SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN" , r, io_cap, a1, a2);
memcpy(m, a2, 7 );
memcpy(m + 7 , a1, 7 );
memcpy(m + 14 , io_cap, 3 );
memcpy(m + 17 , r, 16 );
memcpy(m + 33 , n2, 16 );
memcpy(m + 49 , n1, 16 );
err = aes_cmac(tfm_cmac, w, m, sizeof (m), res);
if (err)
return err;
SMP_DBG("res %16phN" , res);
return err;
}
static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32 ], const u8 v[32 ],
const u8 x[16 ], const u8 y[16 ], u32 *val)
{
u8 m[80 ], tmp[16 ];
int err;
SMP_DBG("u %32phN" , u);
SMP_DBG("v %32phN" , v);
SMP_DBG("x %16phN y %16phN" , x, y);
memcpy(m, y, 16 );
memcpy(m + 16 , v, 32 );
memcpy(m + 48 , u, 32 );
err = aes_cmac(tfm_cmac, x, m, sizeof (m), tmp);
if (err)
return err;
*val = get_unaligned_le32(tmp);
*val %= 1000000 ;
SMP_DBG("val %06u" , *val);
return 0 ;
}
static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16 ],
const u8 key_id[4 ], u8 res[16 ])
{
int err;
SMP_DBG("w %16phN key_id %4phN" , w, key_id);
err = aes_cmac(tfm_cmac, w, key_id, 4 , res);
if (err)
return err;
SMP_DBG("res %16phN" , res);
return err;
}
static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16 ],
const u8 salt[16 ], u8 res[16 ])
{
int err;
SMP_DBG("w %16phN salt %16phN" , w, salt);
err = aes_cmac(tfm_cmac, salt, w, 16 , res);
if (err)
return err;
SMP_DBG("res %16phN" , res);
return err;
}
/* The following functions map to the legacy SMP crypto functions e, c1,
* s1 and ah .
*/
static int smp_e(const u8 *k, u8 *r)
{
struct crypto_aes_ctx ctx;
uint8_t tmp[16 ], data[16 ];
int err;
SMP_DBG("k %16phN r %16phN" , k, r);
/* The most significant octet of key corresponds to k[0] */
swap_buf(k, tmp, 16 );
err = aes_expandkey(&ctx, 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 );
aes_encrypt(&ctx, data, data);
/* Most significant octet of encryptedData corresponds to data[0] */
swap_buf(data, r, 16 );
SMP_DBG("r %16phN" , r);
memzero_explicit(&ctx, sizeof (ctx));
return err;
}
static int smp_c1(const u8 k[16 ],
const u8 r[16 ], const u8 preq[7 ], const u8 pres[7 ], u8 _iat,
const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16 ])
{
u8 p1[16 ], p2[16 ];
int err;
SMP_DBG("k %16phN r %16phN" , k, r);
SMP_DBG("iat %u ia %6phN rat %u ra %6phN" , _iat, ia, _rat, ra);
SMP_DBG("preq %7phN pres %7phN" , preq, pres);
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 );
SMP_DBG("p1 %16phN" , p1);
/* res = r XOR p1 */
crypto_xor_cpy(res, r, p1, sizeof (p1));
/* res = e(k, res) */
err = smp_e(k, res);
if (err) {
BT_ERR("Encrypt data error" );
return err;
}
/* p2 = padding || ia || ra */
memcpy(p2, ra, 6 );
memcpy(p2 + 6 , ia, 6 );
memset(p2 + 12 , 0 , 4 );
SMP_DBG("p2 %16phN" , p2);
/* res = res XOR p2 */
crypto_xor(res, p2, sizeof (p2));
/* res = e(k, res) */
err = smp_e(k, res);
if (err)
BT_ERR("Encrypt data error" );
return err;
}
static int smp_s1(const u8 k[16 ],
const u8 r1[16 ], const 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(k, _r);
if (err)
BT_ERR("Encrypt data error" );
return err;
}
static int smp_ah(const u8 irk[16 ], const 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(irk, _res);
if (err) {
BT_ERR("Encrypt error" );
return err;
}
/* The output of the random address function ah is:
* ah ( k , 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, const u8 irk[16 ],
const bdaddr_t *bdaddr)
{
struct l2cap_chan *chan = hdev->smp_data;
u8 hash[3 ];
int err;
if (!chan || !chan->data)
return false ;
bt_dev_dbg(hdev, "RPA %pMR IRK %*phN" , bdaddr, 16 , irk);
err = smp_ah(irk, &bdaddr->b[3 ], hash);
if (err)
return false ;
return !crypto_memneq(bdaddr->b, hash, 3 );
}
int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16 ], bdaddr_t *rpa)
{
struct l2cap_chan *chan = hdev->smp_data;
int err;
if (!chan || !chan->data)
return -EOPNOTSUPP;
get_random_bytes(&rpa->b[3 ], 3 );
rpa->b[5 ] &= 0 x3f; /* Clear two most significant bits */
rpa->b[5 ] |= 0 x40; /* Set second most significant bit */
err = smp_ah(irk, &rpa->b[3 ], rpa->b);
if (err < 0 )
return err;
bt_dev_dbg(hdev, "RPA %pMR" , rpa);
return 0 ;
}
int smp_generate_oob(struct hci_dev *hdev, u8 hash[16 ], u8 rand[16 ])
{
struct l2cap_chan *chan = hdev->smp_data;
struct smp_dev *smp;
int err;
if (!chan || !chan->data)
return -EOPNOTSUPP;
smp = chan->data;
if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
bt_dev_dbg(hdev, "Using debug keys" );
err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk);
if (err)
return err;
memcpy(smp->local_pk, debug_pk, 64 );
smp->debug_key = true ;
} else {
while (true ) {
/* Generate key pair for Secure Connections */
err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk);
if (err)
return err;
/* This is unlikely, but we need to check that
* we didn ' t accidentally generate a debug key .
*/
if (crypto_memneq(smp->local_pk, debug_pk, 64 ))
break ;
}
smp->debug_key = false ;
}
SMP_DBG("OOB Public Key X: %32phN" , smp->local_pk);
SMP_DBG("OOB Public Key Y: %32phN" , smp->local_pk + 32 );
get_random_bytes(smp->local_rand, 16 );
err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
smp->local_rand, 0 , hash);
if (err < 0 )
return err;
memcpy(rand, smp->local_rand, 16 );
smp->local_oob = true ;
return 0 ;
}
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_dev_dbg(conn->hcon->hdev, "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));
iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, iv, 2 , 1 + len);
l2cap_chan_send(chan, &msg, 1 + len, NULL);
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) {
if (authreq & SMP_AUTH_SC)
return BT_SECURITY_FIPS;
else
return BT_SECURITY_HIGH;
} else {
return BT_SECURITY_MEDIUM;
}
}
static __u8 seclevel_to_authreq(__u8 sec_level)
{
switch (sec_level) {
case BT_SECURITY_FIPS:
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 , oob_flag = SMP_OOB_NOT_PRESENT;
if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
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 (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
remote_dist |= SMP_DIST_ID_KEY;
if (hci_dev_test_flag(hdev, HCI_PRIVACY))
local_dist |= SMP_DIST_ID_KEY;
if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
(authreq & SMP_AUTH_SC)) {
struct oob_data *oob_data;
u8 bdaddr_type;
if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
local_dist |= SMP_DIST_LINK_KEY;
remote_dist |= SMP_DIST_LINK_KEY;
}
if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
bdaddr_type = BDADDR_LE_PUBLIC;
else
bdaddr_type = BDADDR_LE_RANDOM;
oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
bdaddr_type);
if (oob_data && oob_data->present) {
set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
oob_flag = SMP_OOB_PRESENT;
memcpy(smp->rr, oob_data->rand256, 16 );
memcpy(smp->pcnf, oob_data->hash256, 16 );
SMP_DBG("OOB Remote Confirmation: %16phN" , smp->pcnf);
SMP_DBG("OOB Remote Random: %16phN" , smp->rr);
}
} else {
authreq &= ~SMP_AUTH_SC;
}
if (rsp == NULL) {
req->io_capability = conn->hcon->io_capability;
req->oob_flag = oob_flag;
req->max_key_size = hdev->le_max_key_size;
req->init_key_dist = local_dist;
req->resp_key_dist = remote_dist;
req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
smp->remote_key_dist = remote_dist;
return ;
}
rsp->io_capability = conn->hcon->io_capability;
rsp->oob_flag = oob_flag;
rsp->max_key_size = hdev->le_max_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(hdev));
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 hci_dev *hdev = conn->hcon->hdev;
struct smp_chan *smp = chan->data;
if (conn->hcon->pending_sec_level == BT_SECURITY_FIPS &&
max_key_size != SMP_MAX_ENC_KEY_SIZE)
return SMP_ENC_KEY_SIZE;
if (max_key_size > hdev->le_max_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;
struct hci_conn *hcon = conn->hcon;
bool complete;
BUG_ON(!smp);
cancel_delayed_work_sync(&smp->security_timer);
complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
mgmt_smp_complete(hcon, complete);
kfree_sensitive(smp->csrk);
kfree_sensitive(smp->responder_csrk);
kfree_sensitive(smp->link_key);
crypto_free_shash(smp->tfm_cmac);
crypto_free_kpp(smp->tfm_ecdh);
/* Ensure that we don't leave any debug key around if debug key
* support hasn ' t been explicitly enabled .
*/
if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
!hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
list_del_rcu(&smp->ltk->list);
kfree_rcu(smp->ltk, rcu);
smp->ltk = NULL;
}
/* 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->responder_ltk) {
list_del_rcu(&smp->responder_ltk->list);
kfree_rcu(smp->responder_ltk, rcu);
}
if (smp->remote_irk) {
list_del_rcu(&smp->remote_irk->list);
kfree_rcu(smp->remote_irk, rcu);
}
}
chan->data = NULL;
kfree_sensitive(smp);
hci_conn_drop(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);
mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
if (chan->data)
smp_chan_destroy(conn);
}
#define JUST_WORKS 0 x00
#define JUST_CFM 0 x01
#define REQ_PASSKEY 0 x02
#define CFM_PASSKEY 0 x03
#define REQ_OOB 0 x04
#define DSP_PASSKEY 0 x05
#define OVERLAP 0 xFF
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 const u8 sc_method[5 ][5 ] = {
{ JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
{ JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
{ DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
{ JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
{ DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
};
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;
if (test_bit(SMP_FLAG_SC, &smp->flags))
return sc_method[remote_io][local_io];
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;
u32 passkey = 0 ;
int ret;
/* Initialize key for JUST WORKS */
memset(smp->tk, 0 , sizeof (smp->tk));
clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
bt_dev_dbg(hcon->hdev, "auth:%u lcl:%u rem:%u" , 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))
smp->method = JUST_CFM;
else
smp->method = get_auth_method(smp, local_io, remote_io);
/* Don't confirm locally initiated pairing attempts */
if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
&smp->flags))
smp->method = JUST_WORKS;
/* Don't bother user space with no IO capabilities */
if (smp->method == JUST_CFM &&
hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
smp->method = JUST_WORKS;
/* If Just Works, Continue with Zero TK and ask user-space for
* confirmation */
if (smp->method == JUST_WORKS) {
ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
hcon->type,
hcon->dst_type,
passkey, 1 );
if (ret)
return ret;
set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
return 0 ;
}
/* If this function is used for SC -> legacy fallback we
* can only recover the just - works case .
*/
if (test_bit(SMP_FLAG_SC, &smp->flags))
return -EINVAL;
/* Not Just Works/Confirm results in MITM Authentication */
if (smp->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 Keyboard-Display I/O, the initiator
* Confirms and the responder Enters the passkey .
*/
if (smp->method == OVERLAP) {
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags))
smp->method = CFM_PASSKEY;
else
smp->method = REQ_PASSKEY;
}
/* Generate random passkey. */
if (smp->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_dev_dbg(hcon->hdev, "PassKey: %u" , passkey);
set_bit(SMP_FLAG_TK_VALID, &smp->flags);
}
if (smp->method == REQ_PASSKEY)
ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
hcon->type, hcon->dst_type);
else if (smp->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_dev_dbg(conn->hcon->hdev, "conn %p" , conn);
ret = smp_c1(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 (test_bit(SMP_FLAG_INITIATOR, &smp->flags))
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;
bt_dev_dbg(conn->hcon->hdev, "conn %p %s" , conn,
test_bit(SMP_FLAG_INITIATOR, &smp->flags) ? "initiator" :
"responder" );
ret = smp_c1(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 (crypto_memneq(smp->pcnf, confirm, sizeof (smp->pcnf))) {
bt_dev_err(hcon->hdev, "pairing failed "
"(confirmation values mismatch)" );
return SMP_CONFIRM_FAILED;
}
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
u8 stk[16 ];
__le64 rand = 0 ;
__le16 ediv = 0 ;
smp_s1(smp->tk, smp->rrnd, smp->prnd, stk);
if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
return SMP_UNSPECIFIED;
hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
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->tk, smp->prnd, smp->rrnd, stk);
if (hcon->pending_sec_level == BT_SECURITY_HIGH)
auth = 1 ;
else
auth = 0 ;
/* Even though there's no _RESPONDER suffix this is the
* responder STK we ' re adding for later lookup ( the initiator
* 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 (hcon->type == ACL_LINK) {
if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
persistent = false ;
else
persistent = !test_bit(HCI_CONN_FLUSH_KEY,
&hcon->flags);
} else {
/* The LTKs, IRKs 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->remote_irk) {
mgmt_new_irk(hdev, smp->remote_irk, persistent);
/* Now that user space can be considered to know the
* identity address track the connection based on it
* from now on ( assuming this is an LE link ) .
*/
if (hcon->type == LE_LINK) {
bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
hcon->dst_type = smp->remote_irk->addr_type;
/* Use a short delay to make sure the new address is
* propagated _ before_ the channels .
*/
queue_delayed_work(hdev->workqueue,
&conn->id_addr_timer,
ID_ADDR_TIMEOUT);
}
}
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->responder_csrk) {
smp->responder_csrk->bdaddr_type = hcon->dst_type;
bacpy(&smp->responder_csrk->bdaddr, &hcon->dst);
mgmt_new_csrk(hdev, smp->responder_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->responder_ltk) {
smp->responder_ltk->bdaddr_type = hcon->dst_type;
bacpy(&smp->responder_ltk->bdaddr, &hcon->dst);
mgmt_new_ltk(hdev, smp->responder_ltk, persistent);
}
if (smp->link_key) {
struct link_key *key;
u8 type;
if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
type = HCI_LK_DEBUG_COMBINATION;
else if (hcon->sec_level == BT_SECURITY_FIPS)
type = HCI_LK_AUTH_COMBINATION_P256;
else
type = HCI_LK_UNAUTH_COMBINATION_P256;
key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
smp->link_key, type, 0 , &persistent);
if (key) {
mgmt_new_link_key(hdev, key, persistent);
/* Don't keep debug keys around if the relevant
* flag is not set .
*/
if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
key->type == HCI_LK_DEBUG_COMBINATION) {
list_del_rcu(&key->list);
kfree_rcu(key, rcu);
}
}
}
}
static void sc_add_ltk(struct smp_chan *smp)
{
struct hci_conn *hcon = smp->conn->hcon;
u8 key_type, auth;
if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
key_type = SMP_LTK_P256_DEBUG;
else
key_type = SMP_LTK_P256;
if (hcon->pending_sec_level == BT_SECURITY_FIPS)
auth = 1 ;
else
auth = 0 ;
smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
key_type, auth, smp->tk, smp->enc_key_size,
0 , 0 );
}
static void sc_generate_link_key(struct smp_chan *smp)
{
/* From core spec. Spells out in ASCII as 'lebr'. */
const u8 lebr[4 ] = { 0 x72, 0 x62, 0 x65, 0 x6c };
smp->link_key = kzalloc(16 , GFP_KERNEL);
if (!smp->link_key)
return ;
if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
/* SALT = 0x000000000000000000000000746D7031 */
const u8 salt[16 ] = { 0 x31, 0 x70, 0 x6d, 0 x74 };
if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) {
kfree_sensitive(smp->link_key);
smp->link_key = NULL;
return ;
}
} else {
/* From core spec. Spells out in ASCII as 'tmp1'. */
const u8 tmp1[4 ] = { 0 x31, 0 x70, 0 x6d, 0 x74 };
if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
kfree_sensitive(smp->link_key);
smp->link_key = NULL;
return ;
}
}
if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
kfree_sensitive(smp->link_key);
smp->link_key = NULL;
return ;
}
}
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 sc_generate_ltk(struct smp_chan *smp)
{
/* From core spec. Spells out in ASCII as 'brle'. */
const u8 brle[4 ] = { 0 x65, 0 x6c, 0 x72, 0 x62 };
struct hci_conn *hcon = smp->conn->hcon;
struct hci_dev *hdev = hcon->hdev;
struct link_key *key;
key = hci_find_link_key(hdev, &hcon->dst);
if (!key) {
bt_dev_err(hdev, "no Link Key found to generate LTK" );
return ;
}
if (key->type == HCI_LK_DEBUG_COMBINATION)
set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
/* SALT = 0x000000000000000000000000746D7032 */
const u8 salt[16 ] = { 0 x32, 0 x70, 0 x6d, 0 x74 };
if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk))
return ;
} else {
/* From core spec. Spells out in ASCII as 'tmp2'. */
const u8 tmp2[4 ] = { 0 x32, 0 x70, 0 x6d, 0 x74 };
if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
return ;
}
if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
return ;
sc_add_ltk(smp);
}
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_dev_dbg(hdev, "conn %p" , conn);
rsp = (void *) &smp->prsp[1 ];
/* The responder sends its keys first */
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags) &&
(smp->remote_key_dist & KEY_DIST_MASK)) {
smp_allow_key_dist(smp);
return ;
}
req = (void *) &smp->preq[1 ];
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
keydist = &rsp->init_key_dist;
*keydist &= req->init_key_dist;
} else {
keydist = &rsp->resp_key_dist;
*keydist &= req->resp_key_dist;
}
if (test_bit(SMP_FLAG_SC, &smp->flags)) {
if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
sc_generate_link_key(smp);
if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
sc_generate_ltk(smp);
/* Clear the keys which are generated but not distributed */
*keydist &= ~SMP_SC_NO_DIST;
}
bt_dev_dbg(hdev, "keydist 0x%x" , *keydist);
if (*keydist & SMP_DIST_ENC_KEY) {
struct smp_cmd_encrypt_info enc;
struct smp_cmd_initiator_ident ident;
struct smp_ltk *ltk;
u8 authenticated;
__le16 ediv;
__le64 rand;
/* Make sure we generate only the significant amount of
* bytes based on the encryption key size , and set the rest
* of the value to zeroes .
*/
get_random_bytes(enc.ltk, smp->enc_key_size);
memset(enc.ltk + smp->enc_key_size, 0 ,
sizeof (enc.ltk) - smp->enc_key_size);
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_RESPONDER, authenticated, enc.ltk,
smp->enc_key_size, ediv, rand);
smp->responder_ltk = ltk;
ident.ediv = ediv;
ident.rand = rand;
smp_send_cmd(conn, SMP_CMD_INITIATOR_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) {
if (hcon->sec_level > BT_SECURITY_MEDIUM)
csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
else
csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
memcpy(csrk->val, sign.csrk, sizeof (csrk->val));
}
smp->responder_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_dev_dbg(conn->hcon->hdev, "conn %p" , conn);
hci_disconnect(conn->hcon, HCI_ERROR_AUTH_FAILURE);
}
static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
{
struct hci_conn *hcon = conn->hcon;
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp;
smp = kzalloc(sizeof (*smp), GFP_ATOMIC);
if (!smp)
return NULL;
smp->tfm_cmac = crypto_alloc_shash("cmac(aes)" , 0 , 0 );
if (IS_ERR(smp->tfm_cmac)) {
bt_dev_err(hcon->hdev, "Unable to create CMAC crypto context" );
goto zfree_smp;
}
smp->tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256" , 0 , 0 );
if (IS_ERR(smp->tfm_ecdh)) {
bt_dev_err(hcon->hdev, "Unable to create ECDH crypto context" );
goto free_shash;
}
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(hcon);
return smp;
free_shash:
crypto_free_shash(smp->tfm_cmac);
zfree_smp:
kfree_sensitive(smp);
return NULL;
}
static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16 ], u8 ltk[16 ])
{
struct hci_conn *hcon = smp->conn->hcon;
u8 *na, *nb, a[7 ], b[7 ];
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
na = smp->prnd;
nb = smp->rrnd;
} else {
na = smp->rrnd;
nb = smp->prnd;
}
memcpy(a, &hcon->init_addr, 6 );
memcpy(b, &hcon->resp_addr, 6 );
a[6 ] = hcon->init_addr_type;
b[6 ] = hcon->resp_addr_type;
return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
}
static void sc_dhkey_check(struct smp_chan *smp)
{
struct hci_conn *hcon = smp->conn->hcon;
struct smp_cmd_dhkey_check check;
u8 a[7 ], b[7 ], *local_addr, *remote_addr;
u8 io_cap[3 ], r[16 ];
memcpy(a, &hcon->init_addr, 6 );
memcpy(b, &hcon->resp_addr, 6 );
a[6 ] = hcon->init_addr_type;
b[6 ] = hcon->resp_addr_type;
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
local_addr = a;
remote_addr = b;
memcpy(io_cap, &smp->preq[1 ], 3 );
} else {
local_addr = b;
remote_addr = a;
memcpy(io_cap, &smp->prsp[1 ], 3 );
}
memset(r, 0 , sizeof (r));
if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
put_unaligned_le32(hcon->passkey_notify, r);
if (smp->method == REQ_OOB)
memcpy(r, smp->rr, 16 );
smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
local_addr, remote_addr, check.e);
smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof (check), &check);
}
static u8 sc_passkey_send_confirm(struct smp_chan *smp)
{
struct l2cap_conn *conn = smp->conn;
struct hci_conn *hcon = conn->hcon;
struct smp_cmd_pairing_confirm cfm;
u8 r;
r = ((hcon->passkey_notify >> smp->passkey_round) & 0 x01);
r |= 0 x80;
get_random_bytes(smp->prnd, sizeof (smp->prnd));
if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
cfm.confirm_val))
return SMP_UNSPECIFIED;
smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof (cfm), &cfm);
return 0 ;
}
static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
{
struct l2cap_conn *conn = smp->conn;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
u8 cfm[16 ], r;
/* Ignore the PDU if we've already done 20 rounds (0 - 19) */
if (smp->passkey_round >= 20 )
return 0 ;
switch (smp_op) {
case SMP_CMD_PAIRING_RANDOM:
r = ((hcon->passkey_notify >> smp->passkey_round) & 0 x01);
r |= 0 x80;
if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
smp->rrnd, r, cfm))
return SMP_UNSPECIFIED;
if (crypto_memneq(smp->pcnf, cfm, 16 ))
return SMP_CONFIRM_FAILED;
smp->passkey_round++;
if (smp->passkey_round == 20 ) {
/* Generate MacKey and LTK */
if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
return SMP_UNSPECIFIED;
}
/* The round is only complete when the initiator
* receives pairing random .
*/
if (!test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
sizeof (smp->prnd), smp->prnd);
if (smp->passkey_round == 20 )
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
else
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
return 0 ;
}
/* Start the next round */
if (smp->passkey_round != 20 )
return sc_passkey_round(smp, 0 );
/* Passkey rounds are complete - start DHKey Check */
sc_dhkey_check(smp);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
break ;
case SMP_CMD_PAIRING_CONFIRM:
if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
return 0 ;
}
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
sizeof (smp->prnd), smp->prnd);
return 0 ;
}
return sc_passkey_send_confirm(smp);
case SMP_CMD_PUBLIC_KEY:
default :
/* Initiating device starts the round */
if (!test_bit(SMP_FLAG_INITIATOR, &smp->flags))
return 0 ;
bt_dev_dbg(hdev, "Starting passkey round %u" ,
smp->passkey_round + 1 );
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
return sc_passkey_send_confirm(smp);
}
return 0 ;
}
static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
{
struct l2cap_conn *conn = smp->conn;
struct hci_conn *hcon = conn->hcon;
u8 smp_op;
clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
switch (mgmt_op) {
case MGMT_OP_USER_PASSKEY_NEG_REPLY:
smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
return 0 ;
case MGMT_OP_USER_CONFIRM_NEG_REPLY:
smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
return 0 ;
case MGMT_OP_USER_PASSKEY_REPLY:
hcon->passkey_notify = le32_to_cpu(passkey);
smp->passkey_round = 0 ;
if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
smp_op = SMP_CMD_PAIRING_CONFIRM;
else
smp_op = 0 ;
if (sc_passkey_round(smp, smp_op))
return -EIO;
return 0 ;
}
/* Initiator sends DHKey check first */
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
sc_dhkey_check(smp);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
} else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
sc_dhkey_check(smp);
sc_add_ltk(smp);
}
return 0 ;
}
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;
if (!conn)
return -ENOTCONN;
bt_dev_dbg(conn->hcon->hdev, "" );
chan = conn->smp;
if (!chan)
return -ENOTCONN;
l2cap_chan_lock(chan);
if (!chan->data) {
err = -ENOTCONN;
goto unlock;
}
smp = chan->data;
if (test_bit(SMP_FLAG_SC, &smp->flags)) {
err = sc_user_reply(smp, mgmt_op, passkey);
goto unlock;
}
switch (mgmt_op) {
case MGMT_OP_USER_PASSKEY_REPLY:
value = le32_to_cpu(passkey);
memset(smp->tk, 0 , sizeof (smp->tk));
bt_dev_dbg(conn->hcon->hdev, "PassKey: %u" , value);
put_unaligned_le32(value, smp->tk);
fallthrough;
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 void build_bredr_pairing_cmd(struct smp_chan *smp,
struct smp_cmd_pairing *req,
struct smp_cmd_pairing *rsp)
{
struct l2cap_conn *conn = smp->conn;
struct hci_dev *hdev = conn->hcon->hdev;
u8 local_dist = 0 , remote_dist = 0 ;
if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
}
if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
remote_dist |= SMP_DIST_ID_KEY;
if (hci_dev_test_flag(hdev, HCI_PRIVACY))
local_dist |= SMP_DIST_ID_KEY;
if (!rsp) {
memset(req, 0 , sizeof (*req));
req->auth_req = SMP_AUTH_CT2;
req->init_key_dist = local_dist;
req->resp_key_dist = remote_dist;
req->max_key_size = conn->hcon->enc_key_size;
smp->remote_key_dist = remote_dist;
return ;
}
memset(rsp, 0 , sizeof (*rsp));
rsp->auth_req = SMP_AUTH_CT2;
rsp->max_key_size = conn->hcon->enc_key_size;
rsp->init_key_dist = req->init_key_dist & remote_dist;
rsp->resp_key_dist = req->resp_key_dist & local_dist;
smp->remote_key_dist = rsp->init_key_dist;
}
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 = chan->data;
u8 key_size, auth, sec_level;
int ret;
bt_dev_dbg(hdev, "conn %p" , conn);
if (skb->len < sizeof (*req))
return SMP_INVALID_PARAMS;
if (smp && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
return SMP_CMD_NOTSUPP;
if (!smp) {
smp = smp_chan_create(conn);
if (!smp)
return SMP_UNSPECIFIED;
}
/* We didn't start the pairing, so match remote */
auth = req->auth_req & AUTH_REQ_MASK(hdev);
if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
(auth & SMP_AUTH_BONDING))
return SMP_PAIRING_NOTSUPP;
if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
return SMP_AUTH_REQUIREMENTS;
smp->preq[0 ] = SMP_CMD_PAIRING_REQ;
memcpy(&smp->preq[1 ], req, sizeof (*req));
skb_pull(skb, sizeof (*req));
/* If the remote side's OOB flag is set it means it has
* successfully received our local OOB data - therefore set the
* flag to indicate that local OOB is in use .
*/
if (req->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob)
set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
/* SMP over BR/EDR requires special treatment */
if (conn->hcon->type == ACL_LINK) {
/* We must have a BR/EDR SC link */
if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
return SMP_CROSS_TRANSP_NOT_ALLOWED;
set_bit(SMP_FLAG_SC, &smp->flags);
build_bredr_pairing_cmd(smp, req, &rsp);
if (req->auth_req & SMP_AUTH_CT2)
set_bit(SMP_FLAG_CT2, &smp->flags);
key_size = min(req->max_key_size, rsp.max_key_size);
if (check_enc_key_size(conn, key_size))
return SMP_ENC_KEY_SIZE;
/* Clear bits which are generated but not distributed */
smp->remote_key_dist &= ~SMP_SC_NO_DIST;
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_distribute_keys(smp);
return 0 ;
}
build_pairing_cmd(conn, req, &rsp, auth);
if (rsp.auth_req & SMP_AUTH_SC) {
set_bit(SMP_FLAG_SC, &smp->flags);
if (rsp.auth_req & SMP_AUTH_CT2)
set_bit(SMP_FLAG_CT2, &smp->flags);
}
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;
}
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);
clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
/* Strictly speaking we shouldn't allow Pairing Confirm for the
* SC case , however some implementations incorrectly copy RFU auth
* req bits from our security request , which may create a false
* positive SC enablement .
*/
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
if (test_bit(SMP_FLAG_SC, &smp->flags)) {
SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
/* Clear bits which are generated but not distributed */
smp->remote_key_dist &= ~SMP_SC_NO_DIST;
/* Wait for Public Key from Initiating Device */
return 0 ;
}
/* 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 sc_send_public_key(struct smp_chan *smp)
{
struct hci_dev *hdev = smp->conn->hcon->hdev;
bt_dev_dbg(hdev, "" );
if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
struct l2cap_chan *chan = hdev->smp_data;
struct smp_dev *smp_dev;
if (!chan || !chan->data)
return SMP_UNSPECIFIED;
smp_dev = chan->data;
memcpy(smp->local_pk, smp_dev->local_pk, 64 );
memcpy(smp->lr, smp_dev->local_rand, 16 );
if (smp_dev->debug_key)
set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
goto done;
}
if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
bt_dev_dbg(hdev, "Using debug keys" );
if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk))
return SMP_UNSPECIFIED;
memcpy(smp->local_pk, debug_pk, 64 );
set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
} else {
while (true ) {
/* Generate key pair for Secure Connections */
if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk))
return SMP_UNSPECIFIED;
/* This is unlikely, but we need to check that
* we didn ' t accidentally generate a debug key .
*/
if (crypto_memneq(smp->local_pk, debug_pk, 64 ))
break ;
}
}
done:
SMP_DBG("Local Public Key X: %32phN" , smp->local_pk);
SMP_DBG("Local Public Key Y: %32phN" , smp->local_pk + 32 );
smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64 , smp->local_pk);
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;
struct hci_dev *hdev = conn->hcon->hdev;
u8 key_size, auth;
int ret;
bt_dev_dbg(hdev, "conn %p" , conn);
if (skb->len < sizeof (*rsp))
return SMP_INVALID_PARAMS;
if (!test_bit(SMP_FLAG_INITIATOR, &smp->flags))
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(hdev);
if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
return SMP_AUTH_REQUIREMENTS;
/* If the remote side's OOB flag is set it means it has
* successfully received our local OOB data - therefore set the
* flag to indicate that local OOB is in use .
*/
if (rsp->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob)
set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
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;
if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2))
set_bit(SMP_FLAG_CT2, &smp->flags);
/* For BR/EDR this means we're done and can start phase 3 */
if (conn->hcon->type == ACL_LINK) {
/* Clear bits which are generated but not distributed */
smp->remote_key_dist &= ~SMP_SC_NO_DIST;
smp_distribute_keys(smp);
return 0 ;
}
if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
set_bit(SMP_FLAG_SC, &smp->flags);
else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
/* 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));
/* 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;
if (test_bit(SMP_FLAG_SC, &smp->flags)) {
/* Clear bits which are generated but not distributed */
smp->remote_key_dist &= ~SMP_SC_NO_DIST;
SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
return sc_send_public_key(smp);
}
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 sc_check_confirm(struct smp_chan *smp)
{
struct l2cap_conn *conn = smp->conn;
bt_dev_dbg(conn->hcon->hdev, "" );
if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof (smp->prnd),
smp->prnd);
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
}
return 0 ;
}
/* Work-around for some implementations that incorrectly copy RFU bits
* from our security request and thereby create the impression that
* we ' re doing SC when in fact the remote doesn ' t support it .
*/
static int fixup_sc_false_positive(struct smp_chan *smp)
{
struct l2cap_conn *conn = smp->conn;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
struct smp_cmd_pairing *req, *rsp;
u8 auth;
/* The issue is only observed when we're in responder role */
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags))
return SMP_UNSPECIFIED;
if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
bt_dev_err(hdev, "refusing legacy fallback in SC-only mode" );
return SMP_UNSPECIFIED;
}
bt_dev_err(hdev, "trying to fall back to legacy SMP" );
req = (void *) &smp->preq[1 ];
rsp = (void *) &smp->prsp[1 ];
/* Rebuild key dist flags which may have been cleared for SC */
smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
auth = req->auth_req & AUTH_REQ_MASK(hdev);
if (tk_request(conn, 0 , auth, rsp->io_capability, req->io_capability)) {
bt_dev_err(hdev, "failed to fall back to legacy SMP" );
return SMP_UNSPECIFIED;
}
clear_bit(SMP_FLAG_SC, &smp->flags);
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;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
bt_dev_dbg(hdev, "conn %p %s" , conn,
test_bit(SMP_FLAG_INITIATOR, &smp->flags) ? "initiator" :
"responder" );
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 (test_bit(SMP_FLAG_SC, &smp->flags)) {
int ret;
/* Public Key exchange must happen before any other steps */
if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
return sc_check_confirm(smp);
bt_dev_err(hdev, "Unexpected SMP Pairing Confirm" );
ret = fixup_sc_false_positive(smp);
if (ret)
return ret;
}
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
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);
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;
struct hci_conn *hcon = conn->hcon;
u8 *pkax, *pkbx, *na, *nb, confirm_hint;
u32 passkey;
int err;
bt_dev_dbg(hcon->hdev, "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));
if (!test_bit(SMP_FLAG_SC, &smp->flags))
return smp_random(smp);
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
pkax = smp->local_pk;
pkbx = smp->remote_pk;
na = smp->prnd;
nb = smp->rrnd;
} else {
pkax = smp->remote_pk;
pkbx = smp->local_pk;
na = smp->rrnd;
nb = smp->prnd;
}
if (smp->method == REQ_OOB) {
if (!test_bit(SMP_FLAG_INITIATOR, &smp->flags))
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
sizeof (smp->prnd), smp->prnd);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
goto mackey_and_ltk;
}
/* Passkey entry has special treatment */
if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
u8 cfm[16 ];
err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
smp->rrnd, 0 , cfm);
if (err)
return SMP_UNSPECIFIED;
if (crypto_memneq(smp->pcnf, cfm, 16 ))
return SMP_CONFIRM_FAILED;
} else {
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof (smp->prnd),
smp->prnd);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
/* Only Just-Works pairing requires extra checks */
if (smp->method != JUST_WORKS)
goto mackey_and_ltk;
/* If there already exists long term key in local host, leave
* the decision to user space since the remote device could
* be legitimate or malicious .
*/
if (hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
hcon->role)) {
/* Set passkey to 0. The value can be any number since
* it ' ll be ignored anyway .
*/
passkey = 0 ;
confirm_hint = 1 ;
goto confirm;
}
}
mackey_and_ltk:
/* Generate MacKey and LTK */
err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
if (err)
return SMP_UNSPECIFIED;
if (smp->method == REQ_OOB) {
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
sc_dhkey_check(smp);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
}
return 0 ;
}
err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
if (err)
return SMP_UNSPECIFIED;
confirm_hint = 0 ;
confirm:
if (smp->method == JUST_WORKS)
confirm_hint = 1 ;
err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
hcon->dst_type, passkey, confirm_hint);
if (err)
return SMP_UNSPECIFIED;
set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
return 0 ;
}
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(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, key->enc_size);
hcon->enc_key_size = key->enc_size;
/* We never store STKs for initiator 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(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
return false ;
if (hcon->sec_level >= sec_level)
return true ;
return false ;
}
static void smp_send_pairing_req(struct smp_chan *smp, __u8 auth)
{
struct smp_cmd_pairing cp;
if (smp->conn->hcon->type == ACL_LINK)
build_bredr_pairing_cmd(smp, &cp, NULL);
else
build_pairing_cmd(smp->conn, &cp, NULL, auth);
smp->preq[0 ] = SMP_CMD_PAIRING_REQ;
memcpy(&smp->preq[1 ], &cp, sizeof (cp));
smp_send_cmd(smp->conn, SMP_CMD_PAIRING_REQ, sizeof (cp), &cp);
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
set_bit(SMP_FLAG_INITIATOR, &smp->flags);
}
static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct smp_cmd_security_req *rp = (void *) skb->data;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
struct smp_chan *smp;
u8 sec_level, auth;
bt_dev_dbg(hdev, "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(hdev);
if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
return SMP_AUTH_REQUIREMENTS;
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)) {
/* If link is already encrypted with sufficient security we
* still need refresh encryption as per Core Spec 5 . 0 Vol 3 ,
* Part H 2 . 4 . 6
*/
smp_ltk_encrypt(conn, hcon->sec_level);
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 (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
(auth & SMP_AUTH_BONDING))
return SMP_PAIRING_NOTSUPP;
skb_pull(skb, sizeof (*rp));
smp_send_pairing_req(smp, auth);
return 0 ;
}
static void smp_send_security_req(struct smp_chan *smp, __u8 auth)
{
struct smp_cmd_security_req cp;
cp.auth_req = auth;
smp_send_cmd(smp->conn, SMP_CMD_SECURITY_REQ, sizeof (cp), &cp);
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
}
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_dev_dbg(hcon->hdev, "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 ;
if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
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 ;
chan = conn->smp;
if (!chan) {
bt_dev_err(hcon->hdev, "security requested but not available" );
return 1 ;
}
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);
if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) {
authreq |= SMP_AUTH_SC;
if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED))
authreq |= SMP_AUTH_CT2;
}
/* Don't attempt to set MITM if setting is overridden by debugfs
* Needed to pass certification test SM / MAS / PKE / BV - 01 - C
*/
if (!hci_dev_test_flag(hcon->hdev, HCI_FORCE_NO_MITM)) {
/* 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)
smp_send_pairing_req(smp, authreq);
else
smp_send_security_req(smp, authreq);
ret = 0 ;
unlock:
l2cap_chan_unlock(chan);
return ret;
}
int smp_cancel_and_remove_pairing(struct hci_dev *hdev, bdaddr_t *bdaddr,
u8 addr_type)
{
struct hci_conn *hcon;
struct l2cap_conn *conn;
struct l2cap_chan *chan;
struct smp_chan *smp;
int err;
err = hci_remove_ltk(hdev, bdaddr, addr_type);
hci_remove_irk(hdev, bdaddr, addr_type);
hcon = hci_conn_hash_lookup_le(hdev, bdaddr, addr_type);
if (!hcon)
goto done;
conn = hcon->l2cap_data;
if (!conn)
goto done;
chan = conn->smp;
if (!chan)
goto done;
l2cap_chan_lock(chan);
smp = chan->data;
if (smp) {
/* Set keys to NULL to make sure smp_failure() does not try to
* remove and free already invalidated rcu list entries. */
smp->ltk = NULL;
smp->responder_ltk = NULL;
smp->remote_irk = NULL;
if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
smp_failure(conn, 0 );
else
smp_failure(conn, SMP_UNSPECIFIED);
err = 0 ;
}
l2cap_chan_unlock(chan);
done:
return err;
}
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_dev_dbg(conn->hcon->hdev, "conn %p" , conn);
if (skb->len < sizeof (*rp))
return SMP_INVALID_PARAMS;
/* Pairing is aborted if any blocked keys are distributed */
if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_LTK,
rp->ltk)) {
bt_dev_warn_ratelimited(conn->hcon->hdev,
"LTK blocked for %pMR" ,
&conn->hcon->dst);
return SMP_INVALID_PARAMS;
}
SMP_ALLOW_CMD(smp, SMP_CMD_INITIATOR_IDENT);
skb_pull(skb, sizeof (*rp));
memcpy(smp->tk, rp->ltk, sizeof (smp->tk));
return 0 ;
}
static int smp_cmd_initiator_ident(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct smp_cmd_initiator_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_dev_dbg(hdev, "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_dev_dbg(conn->hcon->hdev, "" );
if (skb->len < sizeof (*info))
return SMP_INVALID_PARAMS;
/* Pairing is aborted if any blocked keys are distributed */
if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_IRK,
info->irk)) {
bt_dev_warn_ratelimited(conn->hcon->hdev,
"Identity key blocked for %pMR" ,
&conn->hcon->dst);
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_dev_dbg(hcon->hdev, "" );
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 .
*
* The Identity Address must also be a Static Random or Public
* Address , which hci_is_identity_address ( ) checks for .
*/
if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
!hci_is_identity_address(&info->bdaddr, info->addr_type)) {
bt_dev_err(hcon->hdev, "ignoring IRK with no identity address" );
goto distribute;
}
/* Drop IRK if peer is using identity address during pairing but is
* providing different address as identity information .
*
* Microsoft Surface Precision Mouse is known to have this bug .
*/
if (hci_is_identity_address(&hcon->dst, hcon->dst_type) &&
(bacmp(&info->bdaddr, &hcon->dst) ||
info->addr_type != hcon->dst_type)) {
bt_dev_err(hcon->hdev,
"ignoring IRK with invalid 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_dev_dbg(conn->hcon->hdev, "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) {
if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
else
csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
memcpy(csrk->val, rp->csrk, sizeof (csrk->val));
}
smp->csrk = csrk;
smp_distribute_keys(smp);
return 0 ;
}
static u8 sc_select_method(struct smp_chan *smp)
{
struct smp_cmd_pairing *local, *remote;
u8 local_mitm, remote_mitm, local_io, remote_io, method;
if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
return REQ_OOB;
/* The preq/prsp contain the raw Pairing Request/Response PDUs
* which are needed as inputs to some crypto functions . To get
* the " struct smp_cmd_pairing " from them we need to skip the
* first byte which contains the opcode .
*/
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
local = (void *) &smp->preq[1 ];
remote = (void *) &smp->prsp[1 ];
} else {
local = (void *) &smp->prsp[1 ];
remote = (void *) &smp->preq[1 ];
}
local_io = local->io_capability;
remote_io = remote->io_capability;
local_mitm = (local->auth_req & SMP_AUTH_MITM);
remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
/* If either side wants MITM, look up the method from the table,
* otherwise use JUST WORKS .
*/
if (local_mitm || remote_mitm)
method = get_auth_method(smp, local_io, remote_io);
else
method = JUST_WORKS;
/* Don't confirm locally initiated pairing attempts */
if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
method = JUST_WORKS;
return method;
}
static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct smp_cmd_public_key *key = (void *) skb->data;
struct hci_conn *hcon = conn->hcon;
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
struct hci_dev *hdev = hcon->hdev;
struct crypto_kpp *tfm_ecdh;
struct smp_cmd_pairing_confirm cfm;
int err;
bt_dev_dbg(hdev, "conn %p" , conn);
if (skb->len < sizeof (*key))
return SMP_INVALID_PARAMS;
/* Check if remote and local public keys are the same and debug key is
* not in use .
*/
if (!test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags) &&
!crypto_memneq(key, smp->local_pk, 64 )) {
bt_dev_err(hdev, "Remote and local public keys are identical" );
return SMP_UNSPECIFIED;
}
memcpy(smp->remote_pk, key, 64 );
if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
smp->rr, 0 , cfm.confirm_val);
if (err)
return SMP_UNSPECIFIED;
if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16 ))
return SMP_CONFIRM_FAILED;
}
/* Non-initiating device sends its public key after receiving
* the key from the initiating device .
*/
if (!test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
err = sc_send_public_key(smp);
if (err)
return err;
}
SMP_DBG("Remote Public Key X: %32phN" , smp->remote_pk);
SMP_DBG("Remote Public Key Y: %32phN" , smp->remote_pk + 32 );
/* Compute the shared secret on the same crypto tfm on which the private
* key was set / generated .
*/
if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
struct l2cap_chan *hchan = hdev->smp_data;
struct smp_dev *smp_dev;
if (!hchan || !hchan->data)
return SMP_UNSPECIFIED;
smp_dev = hchan->data;
tfm_ecdh = smp_dev->tfm_ecdh;
} else {
tfm_ecdh = smp->tfm_ecdh;
}
if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey))
return SMP_UNSPECIFIED;
SMP_DBG("DHKey %32phN" , smp->dhkey);
set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
smp->method = sc_select_method(smp);
bt_dev_dbg(hdev, "selected method 0x%02x" , smp->method);
/* JUST_WORKS and JUST_CFM result in an unauthenticated key */
if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
hcon->pending_sec_level = BT_SECURITY_MEDIUM;
else
hcon->pending_sec_level = BT_SECURITY_FIPS;
if (!crypto_memneq(debug_pk, smp->remote_pk, 64 ))
set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
if (smp->method == DSP_PASSKEY) {
get_random_bytes(&hcon->passkey_notify,
sizeof (hcon->passkey_notify));
hcon->passkey_notify %= 1000000 ;
hcon->passkey_entered = 0 ;
smp->passkey_round = 0 ;
if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
hcon->dst_type,
hcon->passkey_notify,
hcon->passkey_entered))
return SMP_UNSPECIFIED;
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
}
if (smp->method == REQ_OOB) {
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags))
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_INITIATOR, &smp->flags))
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
if (smp->method == REQ_PASSKEY) {
if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
hcon->dst_type))
return SMP_UNSPECIFIED;
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
return 0 ;
}
/* The Initiating device waits for the non-initiating device to
* send the confirm value .
*/
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags))
return 0 ;
err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
0 , cfm.confirm_val);
if (err)
return SMP_UNSPECIFIED;
smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof (cfm), &cfm);
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
return 0 ;
}
static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct smp_cmd_dhkey_check *check = (void *) skb->data;
struct l2cap_chan *chan = conn->smp;
struct hci_conn *hcon = conn->hcon;
struct smp_chan *smp = chan->data;
u8 a[7 ], b[7 ], *local_addr, *remote_addr;
u8 io_cap[3 ], r[16 ], e[16 ];
int err;
bt_dev_dbg(hcon->hdev, "conn %p" , conn);
if (skb->len < sizeof (*check))
return SMP_INVALID_PARAMS;
memcpy(a, &hcon->init_addr, 6 );
memcpy(b, &hcon->resp_addr, 6 );
a[6 ] = hcon->init_addr_type;
b[6 ] = hcon->resp_addr_type;
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
local_addr = a;
remote_addr = b;
memcpy(io_cap, &smp->prsp[1 ], 3 );
} else {
local_addr = b;
remote_addr = a;
memcpy(io_cap, &smp->preq[1 ], 3 );
}
memset(r, 0 , sizeof (r));
if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
put_unaligned_le32(hcon->passkey_notify, r);
else if (smp->method == REQ_OOB)
memcpy(r, smp->lr, 16 );
err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
io_cap, remote_addr, local_addr, e);
if (err)
return SMP_UNSPECIFIED;
if (crypto_memneq(check->e, e, 16 ))
return SMP_DHKEY_CHECK_FAILED;
if (!test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
return 0 ;
}
/* Responder sends DHKey check as response to initiator */
sc_dhkey_check(smp);
}
sc_add_ltk(smp);
if (test_bit(SMP_FLAG_INITIATOR, &smp->flags)) {
hci_le_start_enc(hcon, 0 , 0 , smp->tk, smp->enc_key_size);
hcon->enc_key_size = smp->enc_key_size;
}
return 0 ;
}
static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
struct sk_buff *skb)
{
struct smp_cmd_keypress_notify *kp = (void *) skb->data;
bt_dev_dbg(conn->hcon->hdev, "value 0x%02x" , kp->value);
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 (skb->len < 1 )
return -EILSEQ;
if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
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)) {
/* If there is a context and the command is not allowed consider
* it a failure so the session is cleanup properly .
*/
switch (code) {
case SMP_CMD_IDENT_INFO:
case SMP_CMD_IDENT_ADDR_INFO:
case SMP_CMD_SIGN_INFO:
/* 3.6.1. Key distribution and generation
*
* A device may reject a distributed key by sending the
* Pairing Failed command with the reason set to
* " Key Rejected " .
*/
smp_failure(conn, SMP_KEY_REJECTED);
break ;
}
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_INITIATOR_IDENT:
reason = smp_cmd_initiator_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 ;
case SMP_CMD_PUBLIC_KEY:
reason = smp_cmd_public_key(conn, skb);
break ;
case SMP_CMD_DHKEY_CHECK:
reason = smp_cmd_dhkey_check(conn, skb);
break ;
case SMP_CMD_KEYPRESS_NOTIFY:
reason = smp_cmd_keypress_notify(conn, skb);
break ;
default :
bt_dev_dbg(hcon->hdev, "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_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR" ,
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_dev_dbg(conn->hcon->hdev, "chan %p" , chan);
if (chan->data)
smp_chan_destroy(conn);
conn->smp = NULL;
l2cap_chan_put(chan);
}
static void bredr_pairing(struct l2cap_chan *chan)
{
struct l2cap_conn *conn = chan->conn;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
struct smp_chan *smp;
bt_dev_dbg(hdev, "chan %p" , chan);
/* Only new pairings are interesting */
if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
return ;
/* Don't bother if we're not encrypted */
if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
return ;
/* Only initiator may initiate SMP over BR/EDR */
if (hcon->role != HCI_ROLE_MASTER)
return ;
/* Secure Connections support must be enabled */
if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
return ;
/* BR/EDR must use Secure Connections for SMP */
if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
return ;
/* If our LE support is not enabled don't do anything */
if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
return ;
/* Don't bother if remote LE support is not enabled */
if (!lmp_host_le_capable(hcon))
return ;
/* Remote must support SMP fixed chan for BR/EDR */
if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
return ;
/* Don't bother if SMP is already ongoing */
if (chan->data)
return ;
smp = smp_chan_create(conn);
if (!smp) {
bt_dev_err(hdev, "unable to create SMP context for BR/EDR" );
return ;
}
set_bit(SMP_FLAG_SC, &smp->flags);
bt_dev_dbg(hdev, "starting SMP over BR/EDR" );
smp_send_pairing_req(smp, 0 x00);
}
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_dev_dbg(hcon->hdev, "chan %p" , chan);
if (hcon->type == ACL_LINK) {
bredr_pairing(chan);
return ;
}
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;
struct hci_conn *hcon = conn->hcon;
bt_dev_dbg(hcon->hdev, "chan %p" , chan);
/* No need to call l2cap_chan_hold() here since we already own
* the reference taken in smp_new_conn_cb ( ) . This is just the
* first time that we tie it to a specific pointer . The code in
* l2cap_core . c ensures that there ' s no risk this function won ' t
* get called if smp_new_conn_cb was previously called .
*/
conn->smp = chan;
if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
bredr_pairing(chan);
}
static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
{
int err;
bt_dev_dbg(chan->conn->hcon->hdev, "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)->l2cap.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,
};
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,
};
static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
{
struct l2cap_chan *chan;
struct smp_dev *smp;
struct crypto_shash *tfm_cmac;
struct crypto_kpp *tfm_ecdh;
if (cid == L2CAP_CID_SMP_BREDR) {
smp = NULL;
goto create_chan;
}
smp = kzalloc(sizeof (*smp), GFP_KERNEL);
if (!smp)
return ERR_PTR(-ENOMEM);
tfm_cmac = crypto_alloc_shash("cmac(aes)" , 0 , 0 );
if (IS_ERR(tfm_cmac)) {
bt_dev_err(hdev, "Unable to create CMAC crypto context" );
kfree_sensitive(smp);
return ERR_CAST(tfm_cmac);
}
tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256" , 0 , 0 );
if (IS_ERR(tfm_ecdh)) {
bt_dev_err(hdev, "Unable to create ECDH crypto context" );
crypto_free_shash(tfm_cmac);
kfree_sensitive(smp);
return ERR_CAST(tfm_ecdh);
}
smp->local_oob = false ;
smp->tfm_cmac = tfm_cmac;
smp->tfm_ecdh = tfm_ecdh;
create_chan:
chan = l2cap_chan_create();
if (!chan) {
if (smp) {
crypto_free_shash(smp->tfm_cmac);
crypto_free_kpp(smp->tfm_ecdh);
kfree_sensitive(smp);
}
return ERR_PTR(-ENOMEM);
}
chan->data = smp;
l2cap_add_scid(chan, cid);
l2cap_chan_set_defaults(chan);
if (cid == L2CAP_CID_SMP) {
u8 bdaddr_type;
hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
chan->src_type = BDADDR_LE_PUBLIC;
else
chan->src_type = BDADDR_LE_RANDOM;
} else {
bacpy(&chan->src, &hdev->bdaddr);
chan->src_type = BDADDR_BREDR;
}
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);
return chan;
}
static void smp_del_chan(struct l2cap_chan *chan)
{
struct smp_dev *smp;
BT_DBG("chan %p" , chan);
smp = chan->data;
if (smp) {
chan->data = NULL;
crypto_free_shash(smp->tfm_cmac);
crypto_free_kpp(smp->tfm_ecdh);
kfree_sensitive(smp);
}
l2cap_chan_put(chan);
}
int smp_force_bredr(struct hci_dev *hdev, bool enable)
{
if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
return -EALREADY;
if (enable) {
struct l2cap_chan *chan;
chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
if (IS_ERR(chan))
return PTR_ERR(chan);
hdev->smp_bredr_data = chan;
} else {
struct l2cap_chan *chan;
chan = hdev->smp_bredr_data;
hdev->smp_bredr_data = NULL;
smp_del_chan(chan);
}
hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
return 0 ;
}
int smp_register(struct hci_dev *hdev)
{
struct l2cap_chan *chan;
bt_dev_dbg(hdev, "" );
/* If the controller does not support Low Energy operation, then
* there is also no need to register any SMP channel .
*/
if (!lmp_le_capable(hdev))
return 0 ;
if (WARN_ON(hdev->smp_data)) {
chan = hdev->smp_data;
hdev->smp_data = NULL;
smp_del_chan(chan);
}
chan = smp_add_cid(hdev, L2CAP_CID_SMP);
if (IS_ERR(chan))
return PTR_ERR(chan);
hdev->smp_data = chan;
if (!lmp_sc_capable(hdev)) {
/* Flag can be already set here (due to power toggle) */
if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
return 0 ;
}
if (WARN_ON(hdev->smp_bredr_data)) {
chan = hdev->smp_bredr_data;
hdev->smp_bredr_data = NULL;
smp_del_chan(chan);
}
chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
if (IS_ERR(chan)) {
int err = PTR_ERR(chan);
chan = hdev->smp_data;
hdev->smp_data = NULL;
smp_del_chan(chan);
return err;
}
hdev->smp_bredr_data = chan;
return 0 ;
}
void smp_unregister(struct hci_dev *hdev)
{
struct l2cap_chan *chan;
if (hdev->smp_bredr_data) {
chan = hdev->smp_bredr_data;
hdev->smp_bredr_data = NULL;
smp_del_chan(chan);
}
if (hdev->smp_data) {
chan = hdev->smp_data;
hdev->smp_data = NULL;
smp_del_chan(chan);
}
}
#if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
static int __init test_debug_key(struct crypto_kpp *tfm_ecdh)
{
u8 pk[64 ];
int err;
err = set_ecdh_privkey(tfm_ecdh, debug_sk);
if (err)
return err;
err = generate_ecdh_public_key(tfm_ecdh, pk);
if (err)
return err;
if (crypto_memneq(pk, debug_pk, 64 ))
return -EINVAL;
return 0 ;
}
static int __init test_ah(void )
{
const u8 irk[16 ] = {
0 x9b, 0 x7d, 0 x39, 0 x0a, 0 xa6, 0 x10, 0 x10, 0 x34,
0 x05, 0 xad, 0 xc8, 0 x57, 0 xa3, 0 x34, 0 x02, 0 xec };
const u8 r[3 ] = { 0 x94, 0 x81, 0 x70 };
const u8 exp[3 ] = { 0 xaa, 0 xfb, 0 x0d };
u8 res[3 ];
int err;
err = smp_ah(irk, r, res);
if (err)
return err;
if (crypto_memneq(res, exp, 3 ))
return -EINVAL;
return 0 ;
}
static int __init test_c1(void )
{
const u8 k[16 ] = {
0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00,
0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00 };
const u8 r[16 ] = {
0 xe0, 0 x2e, 0 x70, 0 xc6, 0 x4e, 0 x27, 0 x88, 0 x63,
0 x0e, 0 x6f, 0 xad, 0 x56, 0 x21, 0 xd5, 0 x83, 0 x57 };
const u8 preq[7 ] = { 0 x01, 0 x01, 0 x00, 0 x00, 0 x10, 0 x07, 0 x07 };
const u8 pres[7 ] = { 0 x02, 0 x03, 0 x00, 0 x00, 0 x08, 0 x00, 0 x05 };
const u8 _iat = 0 x01;
const u8 _rat = 0 x00;
const bdaddr_t ra = { { 0 xb6, 0 xb5, 0 xb4, 0 xb3, 0 xb2, 0 xb1 } };
const bdaddr_t ia = { { 0 xa6, 0 xa5, 0 xa4, 0 xa3, 0 xa2, 0 xa1 } };
const u8 exp[16 ] = {
0 x86, 0 x3b, 0 xf1, 0 xbe, 0 xc5, 0 x4d, 0 xa7, 0 xd2,
0 xea, 0 x88, 0 x89, 0 x87, 0 xef, 0 x3f, 0 x1e, 0 x1e };
u8 res[16 ];
int err;
err = smp_c1(k, r, preq, pres, _iat, &ia, _rat, &ra, res);
if (err)
return err;
if (crypto_memneq(res, exp, 16 ))
return -EINVAL;
return 0 ;
}
static int __init test_s1(void )
{
const u8 k[16 ] = {
0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00,
0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00, 0 x00 };
const u8 r1[16 ] = {
0 x88, 0 x77, 0 x66, 0 x55, 0 x44, 0 x33, 0 x22, 0 x11 };
const u8 r2[16 ] = {
0 x00, 0 xff, 0 xee, 0 xdd, 0 xcc, 0 xbb, 0 xaa, 0 x99 };
const u8 exp[16 ] = {
0 x62, 0 xa0, 0 x6d, 0 x79, 0 xae, 0 x16, 0 x42, 0 x5b,
0 x9b, 0 xf4, 0 xb0, 0 xe8, 0 xf0, 0 xe1, 0 x1f, 0 x9a };
u8 res[16 ];
int err;
err = smp_s1(k, r1, r2, res);
if (err)
return err;
if (crypto_memneq(res, exp, 16 ))
return -EINVAL;
return 0 ;
}
static int __init test_f4(struct crypto_shash *tfm_cmac)
{
const u8 u[32 ] = {
0 xe6, 0 x9d, 0 x35, 0 x0e, 0 x48, 0 x01, 0 x03, 0 xcc,
0 xdb, 0 xfd, 0 xf4, 0 xac, 0 x11, 0 x91, 0 xf4, 0 xef,
0 xb9, 0 xa5, 0 xf9, 0 xe9, 0 xa7, 0 x83, 0 x2c, 0 x5e,
0 x2c, 0 xbe, 0 x97, 0 xf2, 0 xd2, 0 x03, 0 xb0, 0 x20 };
const u8 v[32 ] = {
0 xfd, 0 xc5, 0 x7f, 0 xf4, 0 x49, 0 xdd, 0 x4f, 0 x6b,
0 xfb, 0 x7c, 0 x9d, 0 xf1, 0 xc2, 0 x9a, 0 xcb, 0 x59,
0 x2a, 0 xe7, 0 xd4, 0 xee, 0 xfb, 0 xfc, 0 x0a, 0 x90,
0 x9a, 0 xbb, 0 xf6, 0 x32, 0 x3d, 0 x8b, 0 x18, 0 x55 };
const u8 x[16 ] = {
0 xab, 0 xae, 0 x2b, 0 x71, 0 xec, 0 xb2, 0 xff, 0 xff,
0 x3e, 0 x73, 0 x77, 0 xd1, 0 x54, 0 x84, 0 xcb, 0 xd5 };
const u8 z = 0 x00;
const u8 exp[16 ] = {
0 x2d, 0 x87, 0 x74, 0 xa9, 0 xbe, 0 xa1, 0 xed, 0 xf1,
0 x1c, 0 xbd, 0 xa9, 0 x07, 0 xf1, 0 x16, 0 xc9, 0 xf2 };
u8 res[16 ];
int err;
err = smp_f4(tfm_cmac, u, v, x, z, res);
if (err)
return err;
if (crypto_memneq(res, exp, 16 ))
return -EINVAL;
return 0 ;
}
static int __init test_f5(struct crypto_shash *tfm_cmac)
{
const u8 w[32 ] = {
0 x98, 0 xa6, 0 xbf, 0 x73, 0 xf3, 0 x34, 0 x8d, 0 x86,
0 xf1, 0 x66, 0 xf8, 0 xb4, 0 x13, 0 x6b, 0 x79, 0 x99,
0 x9b, 0 x7d, 0 x39, 0 x0a, 0 xa6, 0 x10, 0 x10, 0 x34,
0 x05, 0 xad, 0 xc8, 0 x57, 0 xa3, 0 x34, 0 x02, 0 xec };
const u8 n1[16 ] = {
0 xab, 0 xae, 0 x2b, 0 x71, 0 xec, 0 xb2, 0 xff, 0 xff,
0 x3e, 0 x73, 0 x77, 0 xd1, 0 x54, 0 x84, 0 xcb, 0 xd5 };
const u8 n2[16 ] = {
0 xcf, 0 xc4, 0 x3d, 0 xff, 0 xf7, 0 x83, 0 x65, 0 x21,
0 x6e, 0 x5f, 0 xa7, 0 x25, 0 xcc, 0 xe7, 0 xe8, 0 xa6 };
const u8 a1[7 ] = { 0 xce, 0 xbf, 0 x37, 0 x37, 0 x12, 0 x56, 0 x00 };
const u8 a2[7 ] = { 0 xc1, 0 xcf, 0 x2d, 0 x70, 0 x13, 0 xa7, 0 x00 };
const u8 exp_ltk[16 ] = {
0 x38, 0 x0a, 0 x75, 0 x94, 0 xb5, 0 x22, 0 x05, 0 x98,
0 x23, 0 xcd, 0 xd7, 0 x69, 0 x11, 0 x79, 0 x86, 0 x69 };
const u8 exp_mackey[16 ] = {
0 x20, 0 x6e, 0 x63, 0 xce, 0 x20, 0 x6a, 0 x3f, 0 xfd,
0 x02, 0 x4a, 0 x08, 0 xa1, 0 x76, 0 xf1, 0 x65, 0 x29 };
u8 mackey[16 ], ltk[16 ];
int err;
err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
if (err)
return err;
if (crypto_memneq(mackey, exp_mackey, 16 ))
return -EINVAL;
if (crypto_memneq(ltk, exp_ltk, 16 ))
return -EINVAL;
return 0 ;
}
static int __init test_f6(struct crypto_shash *tfm_cmac)
{
const u8 w[16 ] = {
0 x20, 0 x6e, 0 x63, 0 xce, 0 x20, 0 x6a, 0 x3f, 0 xfd,
0 x02, 0 x4a, 0 x08, 0 xa1, 0 x76, 0 xf1, 0 x65, 0 x29 };
const u8 n1[16 ] = {
0 xab, 0 xae, 0 x2b, 0 x71, 0 xec, 0 xb2, 0 xff, 0 xff,
0 x3e, 0 x73, 0 x77, 0 xd1, 0 x54, 0 x84, 0 xcb, 0 xd5 };
const u8 n2[16 ] = {
0 xcf, 0 xc4, 0 x3d, 0 xff, 0 xf7, 0 x83, 0 x65, 0 x21,
0 x6e, 0 x5f, 0 xa7, 0 x25, 0 xcc, 0 xe7, 0 xe8, 0 xa6 };
const u8 r[16 ] = {
0 xc8, 0 x0f, 0 x2d, 0 x0c, 0 xd2, 0 x42, 0 xda, 0 x08,
0 x54, 0 xbb, 0 x53, 0 xb4, 0 x3b, 0 x34, 0 xa3, 0 x12 };
const u8 io_cap[3 ] = { 0 x02, 0 x01, 0 x01 };
const u8 a1[7 ] = { 0 xce, 0 xbf, 0 x37, 0 x37, 0 x12, 0 x56, 0 x00 };
const u8 a2[7 ] = { 0 xc1, 0 xcf, 0 x2d, 0 x70, 0 x13, 0 xa7, 0 x00 };
const u8 exp[16 ] = {
0 x61, 0 x8f, 0 x95, 0 xda, 0 x09, 0 x0b, 0 x6c, 0 xd2,
0 xc5, 0 xe8, 0 xd0, 0 x9c, 0 x98, 0 x73, 0 xc4, 0 xe3 };
u8 res[16 ];
int err;
err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
if (err)
return err;
if (crypto_memneq(res, exp, 16 ))
return -EINVAL;
return 0 ;
}
static int __init test_g2(struct crypto_shash *tfm_cmac)
{
const u8 u[32 ] = {
0 xe6, 0 x9d, 0 x35, 0 x0e, 0 x48, 0 x01, 0 x03, 0 xcc,
0 xdb, 0 xfd, 0 xf4, 0 xac, 0 x11, 0 x91, 0 xf4, 0 xef,
0 xb9, 0 xa5, 0 xf9, 0 xe9, 0 xa7, 0 x83, 0 x2c, 0 x5e,
0 x2c, 0 xbe, 0 x97, 0 xf2, 0 xd2, 0 x03, 0 xb0, 0 x20 };
const u8 v[32 ] = {
0 xfd, 0 xc5, 0 x7f, 0 xf4, 0 x49, 0 xdd, 0 x4f, 0 x6b,
0 xfb, 0 x7c, 0 x9d, 0 xf1, 0 xc2, 0 x9a, 0 xcb, 0 x59,
0 x2a, 0 xe7, 0 xd4, 0 xee, 0 xfb, 0 xfc, 0 x0a, 0 x90,
0 x9a, 0 xbb, 0 xf6, 0 x32, 0 x3d, 0 x8b, 0 x18, 0 x55 };
const u8 x[16 ] = {
0 xab, 0 xae, 0 x2b, 0 x71, 0 xec, 0 xb2, 0 xff, 0 xff,
0 x3e, 0 x73, 0 x77, 0 xd1, 0 x54, 0 x84, 0 xcb, 0 xd5 };
const u8 y[16 ] = {
0 xcf, 0 xc4, 0 x3d, 0 xff, 0 xf7, 0 x83, 0 x65, 0 x21,
0 x6e, 0 x5f, 0 xa7, 0 x25, 0 xcc, 0 xe7, 0 xe8, 0 xa6 };
const u32 exp_val = 0 x2f9ed5ba % 1000000 ;
u32 val;
int err;
err = smp_g2(tfm_cmac, u, v, x, y, &val);
if (err)
return err;
if (val != exp_val)
return -EINVAL;
return 0 ;
}
static int __init test_h6(struct crypto_shash *tfm_cmac)
{
const u8 w[16 ] = {
0 x9b, 0 x7d, 0 x39, 0 x0a, 0 xa6, 0 x10, 0 x10, 0 x34,
0 x05, 0 xad, 0 xc8, 0 x57, 0 xa3, 0 x34, 0 x02, 0 xec };
const u8 key_id[4 ] = { 0 x72, 0 x62, 0 x65, 0 x6c };
const u8 exp[16 ] = {
0 x99, 0 x63, 0 xb1, 0 x80, 0 xe2, 0 xa9, 0 xd3, 0 xe8,
0 x1c, 0 xc9, 0 x6d, 0 xe7, 0 x02, 0 xe1, 0 x9a, 0 x2d };
u8 res[16 ];
int err;
err = smp_h6(tfm_cmac, w, key_id, res);
if (err)
return err;
if (crypto_memneq(res, exp, 16 ))
return -EINVAL;
return 0 ;
}
static char test_smp_buffer[32 ];
static ssize_t test_smp_read(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
strlen(test_smp_buffer));
}
static const struct file_operations test_smp_fops = {
.open = simple_open,
.read = test_smp_read,
.llseek = default_llseek,
};
static int __init run_selftests(struct crypto_shash *tfm_cmac,
struct crypto_kpp *tfm_ecdh)
{
ktime_t calltime, delta, rettime;
unsigned long long duration;
int err;
calltime = ktime_get();
err = test_debug_key(tfm_ecdh);
if (err) {
BT_ERR("debug_key test failed" );
goto done;
}
err = test_ah();
if (err) {
BT_ERR("smp_ah test failed" );
goto done;
}
err = test_c1();
if (err) {
BT_ERR("smp_c1 test failed" );
goto done;
}
err = test_s1();
if (err) {
BT_ERR("smp_s1 test failed" );
goto done;
}
err = test_f4(tfm_cmac);
if (err) {
BT_ERR("smp_f4 test failed" );
goto done;
}
err = test_f5(tfm_cmac);
if (err) {
BT_ERR("smp_f5 test failed" );
goto done;
}
err = test_f6(tfm_cmac);
if (err) {
BT_ERR("smp_f6 test failed" );
goto done;
}
err = test_g2(tfm_cmac);
if (err) {
BT_ERR("smp_g2 test failed" );
goto done;
}
err = test_h6(tfm_cmac);
if (err) {
BT_ERR("smp_h6 test failed" );
goto done;
}
rettime = ktime_get();
delta = ktime_sub(rettime, calltime);
duration = (unsigned long long ) ktime_to_ns(delta) >> 10 ;
BT_INFO("SMP test passed in %llu usecs" , duration);
done:
if (!err)
snprintf(test_smp_buffer, sizeof (test_smp_buffer),
"PASS (%llu usecs)\n" , duration);
else
snprintf(test_smp_buffer, sizeof (test_smp_buffer), "FAIL\n" );
debugfs_create_file("selftest_smp" , 0444 , bt_debugfs, NULL,
&test_smp_fops);
return err;
}
int __init bt_selftest_smp(void )
{
struct crypto_shash *tfm_cmac;
struct crypto_kpp *tfm_ecdh;
int err;
tfm_cmac = crypto_alloc_shash("cmac(aes)" , 0 , 0 );
if (IS_ERR(tfm_cmac)) {
BT_ERR("Unable to create CMAC crypto context" );
return PTR_ERR(tfm_cmac);
}
tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256" , 0 , 0 );
if (IS_ERR(tfm_ecdh)) {
BT_ERR("Unable to create ECDH crypto context" );
crypto_free_shash(tfm_cmac);
return PTR_ERR(tfm_ecdh);
}
err = run_selftests(tfm_cmac, tfm_ecdh);
crypto_free_shash(tfm_cmac);
crypto_free_kpp(tfm_ecdh);
return err;
}
#endif
Messung V0.5 in Prozent C=97 H=96 G=96
¤ Dauer der Verarbeitung: 0.178 Sekunden
(vorverarbeitet am 2026-09-28)
¤
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