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Diffstat (limited to 'net/bluetooth/smp.c')
-rw-r--r--net/bluetooth/smp.c585
1 files changed, 460 insertions, 125 deletions
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 45007362683b..dfb4e1161c10 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -35,14 +35,14 @@
#define AUTH_REQ_MASK 0x07
-static inline void swap128(u8 src[16], u8 dst[16])
+static inline void swap128(const u8 src[16], u8 dst[16])
{
int i;
for (i = 0; i < 16; i++)
dst[15 - i] = src[i];
}
-static inline void swap56(u8 src[7], u8 dst[7])
+static inline void swap56(const u8 src[7], u8 dst[7])
{
int i;
for (i = 0; i < 7; i++)
@@ -53,6 +53,7 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
{
struct blkcipher_desc desc;
struct scatterlist sg;
+ uint8_t tmp[16], data[16];
int err;
if (tfm == NULL) {
@@ -63,21 +64,89 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
desc.tfm = tfm;
desc.flags = 0;
- err = crypto_blkcipher_setkey(tfm, k, 16);
+ /* The most significant octet of key corresponds to k[0] */
+ swap128(k, tmp);
+
+ err = crypto_blkcipher_setkey(tfm, tmp, 16);
if (err) {
BT_ERR("cipher setkey failed: %d", err);
return err;
}
- sg_init_one(&sg, r, 16);
+ /* Most significant octet of plaintextData corresponds to data[0] */
+ swap128(r, data);
+
+ sg_init_one(&sg, data, 16);
err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
if (err)
BT_ERR("Encrypt data error %d", err);
+ /* Most significant octet of encryptedData corresponds to data[0] */
+ swap128(data, r);
+
return err;
}
+static int smp_ah(struct crypto_blkcipher *tfm, u8 irk[16], u8 r[3], u8 res[3])
+{
+ u8 _res[16];
+ int err;
+
+ /* r' = padding || r */
+ memcpy(_res, r, 3);
+ memset(_res + 3, 0, 13);
+
+ err = smp_e(tfm, irk, _res);
+ if (err) {
+ BT_ERR("Encrypt error");
+ return err;
+ }
+
+ /* The output of the random address function ah is:
+ * ah(h, r) = e(k, r') mod 2^24
+ * The output of the security function e is then truncated to 24 bits
+ * by taking the least significant 24 bits of the output of e as the
+ * result of ah.
+ */
+ memcpy(res, _res, 3);
+
+ return 0;
+}
+
+bool smp_irk_matches(struct crypto_blkcipher *tfm, u8 irk[16],
+ bdaddr_t *bdaddr)
+{
+ u8 hash[3];
+ int err;
+
+ BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
+
+ err = smp_ah(tfm, irk, &bdaddr->b[3], hash);
+ if (err)
+ return false;
+
+ return !memcmp(bdaddr->b, hash, 3);
+}
+
+int smp_generate_rpa(struct crypto_blkcipher *tfm, u8 irk[16], bdaddr_t *rpa)
+{
+ int err;
+
+ get_random_bytes(&rpa->b[3], 3);
+
+ rpa->b[5] &= 0x3f; /* Clear two most significant bits */
+ rpa->b[5] |= 0x40; /* Set second most significant bit */
+
+ err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);
+ if (err < 0)
+ return err;
+
+ BT_DBG("RPA %pMR", rpa);
+
+ return 0;
+}
+
static int smp_c1(struct crypto_blkcipher *tfm, u8 k[16], u8 r[16],
u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia,
u8 _rat, bdaddr_t *ra, u8 res[16])
@@ -88,16 +157,15 @@ static int smp_c1(struct crypto_blkcipher *tfm, u8 k[16], u8 r[16],
memset(p1, 0, 16);
/* p1 = pres || preq || _rat || _iat */
- swap56(pres, p1);
- swap56(preq, p1 + 7);
- p1[14] = _rat;
- p1[15] = _iat;
-
- memset(p2, 0, 16);
+ p1[0] = _iat;
+ p1[1] = _rat;
+ memcpy(p1 + 2, preq, 7);
+ memcpy(p1 + 9, pres, 7);
/* p2 = padding || ia || ra */
- baswap((bdaddr_t *) (p2 + 4), ia);
- baswap((bdaddr_t *) (p2 + 10), ra);
+ memcpy(p2, ra, 6);
+ memcpy(p2 + 6, ia, 6);
+ memset(p2 + 12, 0, 4);
/* res = r XOR p1 */
u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
@@ -126,8 +194,8 @@ static int smp_s1(struct crypto_blkcipher *tfm, u8 k[16], u8 r1[16],
int err;
/* Just least significant octets from r1 and r2 are considered */
- memcpy(_r, r1 + 8, 8);
- memcpy(_r + 8, r2 + 8, 8);
+ memcpy(_r, r2, 8);
+ memcpy(_r + 8, r1, 8);
err = smp_e(tfm, k, _r);
if (err)
@@ -154,7 +222,7 @@ static struct sk_buff *smp_build_cmd(struct l2cap_conn *conn, u8 code,
lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
lh->len = cpu_to_le16(sizeof(code) + dlen);
- lh->cid = __constant_cpu_to_le16(L2CAP_CID_SMP);
+ lh->cid = cpu_to_le16(L2CAP_CID_SMP);
memcpy(skb_put(skb, sizeof(code)), &code, sizeof(code));
@@ -203,31 +271,45 @@ static void build_pairing_cmd(struct l2cap_conn *conn,
struct smp_cmd_pairing *req,
struct smp_cmd_pairing *rsp, __u8 authreq)
{
- u8 dist_keys = 0;
+ struct smp_chan *smp = conn->smp_chan;
+ struct hci_conn *hcon = conn->hcon;
+ struct hci_dev *hdev = hcon->hdev;
+ u8 local_dist = 0, remote_dist = 0;
if (test_bit(HCI_PAIRABLE, &conn->hcon->hdev->dev_flags)) {
- dist_keys = SMP_DIST_ENC_KEY;
+ local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
+ remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
authreq |= SMP_AUTH_BONDING;
} else {
authreq &= ~SMP_AUTH_BONDING;
}
+ if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags))
+ remote_dist |= SMP_DIST_ID_KEY;
+
+ if (test_bit(HCI_PRIVACY, &hdev->dev_flags))
+ local_dist |= SMP_DIST_ID_KEY;
+
if (rsp == NULL) {
req->io_capability = conn->hcon->io_capability;
req->oob_flag = SMP_OOB_NOT_PRESENT;
req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
- req->init_key_dist = 0;
- req->resp_key_dist = dist_keys;
+ req->init_key_dist = local_dist;
+ req->resp_key_dist = remote_dist;
req->auth_req = (authreq & AUTH_REQ_MASK);
+
+ smp->remote_key_dist = remote_dist;
return;
}
rsp->io_capability = conn->hcon->io_capability;
rsp->oob_flag = SMP_OOB_NOT_PRESENT;
rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
- rsp->init_key_dist = 0;
- rsp->resp_key_dist = req->resp_key_dist & dist_keys;
+ rsp->init_key_dist = req->init_key_dist & remote_dist;
+ rsp->resp_key_dist = req->resp_key_dist & local_dist;
rsp->auth_req = (authreq & AUTH_REQ_MASK);
+
+ smp->remote_key_dist = rsp->init_key_dist;
}
static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
@@ -305,6 +387,11 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
if (!(auth & SMP_AUTH_BONDING) && method == JUST_CFM)
method = JUST_WORKS;
+ /* Don't confirm locally initiated pairing attempts */
+ if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
+ &smp->smp_flags))
+ method = JUST_WORKS;
+
/* If Just Works, Continue with Zero TK */
if (method == JUST_WORKS) {
set_bit(SMP_FLAG_TK_VALID, &smp->smp_flags);
@@ -325,16 +412,14 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
method = REQ_PASSKEY;
}
- /* Generate random passkey. Not valid until confirmed. */
+ /* Generate random passkey. */
if (method == CFM_PASSKEY) {
- u8 key[16];
-
- memset(key, 0, sizeof(key));
+ memset(smp->tk, 0, sizeof(smp->tk));
get_random_bytes(&passkey, sizeof(passkey));
passkey %= 1000000;
- put_unaligned_le32(passkey, key);
- swap128(key, smp->tk);
+ put_unaligned_le32(passkey, smp->tk);
BT_DBG("PassKey: %d", passkey);
+ set_bit(SMP_FLAG_TK_VALID, &smp->smp_flags);
}
hci_dev_lock(hcon->hdev);
@@ -342,10 +427,14 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
if (method == REQ_PASSKEY)
ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
hcon->type, hcon->dst_type);
- else
+ else if (method == JUST_CFM)
ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
hcon->type, hcon->dst_type,
- cpu_to_le32(passkey), 0);
+ passkey, 1);
+ else
+ ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
+ hcon->type, hcon->dst_type,
+ passkey, 0);
hci_dev_unlock(hcon->hdev);
@@ -356,29 +445,24 @@ static void confirm_work(struct work_struct *work)
{
struct smp_chan *smp = container_of(work, struct smp_chan, confirm);
struct l2cap_conn *conn = smp->conn;
- struct crypto_blkcipher *tfm;
+ struct hci_dev *hdev = conn->hcon->hdev;
+ struct crypto_blkcipher *tfm = hdev->tfm_aes;
struct smp_cmd_pairing_confirm cp;
int ret;
- u8 res[16], reason;
+ u8 reason;
BT_DBG("conn %p", conn);
- tfm = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
- if (IS_ERR(tfm)) {
- reason = SMP_UNSPECIFIED;
- goto error;
- }
+ /* Prevent mutual access to hdev->tfm_aes */
+ hci_dev_lock(hdev);
- smp->tfm = tfm;
+ ret = smp_c1(tfm, 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);
+
+ hci_dev_unlock(hdev);
- if (conn->hcon->out)
- ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp,
- conn->hcon->src_type, &conn->hcon->src,
- conn->hcon->dst_type, &conn->hcon->dst, res);
- else
- ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp,
- conn->hcon->dst_type, &conn->hcon->dst,
- conn->hcon->src_type, &conn->hcon->src, res);
if (ret) {
reason = SMP_UNSPECIFIED;
goto error;
@@ -386,7 +470,6 @@ static void confirm_work(struct work_struct *work)
clear_bit(SMP_FLAG_CFM_PENDING, &smp->smp_flags);
- swap128(res, cp.confirm_val);
smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
return;
@@ -400,8 +483,9 @@ static void random_work(struct work_struct *work)
struct smp_chan *smp = container_of(work, struct smp_chan, random);
struct l2cap_conn *conn = smp->conn;
struct hci_conn *hcon = conn->hcon;
- struct crypto_blkcipher *tfm = smp->tfm;
- u8 reason, confirm[16], res[16], key[16];
+ struct hci_dev *hdev = hcon->hdev;
+ struct crypto_blkcipher *tfm = hdev->tfm_aes;
+ u8 reason, confirm[16];
int ret;
if (IS_ERR_OR_NULL(tfm)) {
@@ -411,21 +495,20 @@ static void random_work(struct work_struct *work)
BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
- if (hcon->out)
- ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp,
- hcon->src_type, &hcon->src,
- hcon->dst_type, &hcon->dst, res);
- else
- ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp,
- hcon->dst_type, &hcon->dst,
- hcon->src_type, &hcon->src, res);
+ /* Prevent mutual access to hdev->tfm_aes */
+ hci_dev_lock(hdev);
+
+ ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp,
+ hcon->init_addr_type, &hcon->init_addr,
+ hcon->resp_addr_type, &hcon->resp_addr, confirm);
+
+ hci_dev_unlock(hdev);
+
if (ret) {
reason = SMP_UNSPECIFIED;
goto error;
}
- swap128(res, confirm);
-
if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
BT_ERR("Pairing failed (confirmation values mismatch)");
reason = SMP_CONFIRM_FAILED;
@@ -433,14 +516,11 @@ static void random_work(struct work_struct *work)
}
if (hcon->out) {
- u8 stk[16], rand[8];
- __le16 ediv;
-
- memset(rand, 0, sizeof(rand));
- ediv = 0;
+ u8 stk[16];
+ __le64 rand = 0;
+ __le16 ediv = 0;
- smp_s1(tfm, smp->tk, smp->rrnd, smp->prnd, key);
- swap128(key, stk);
+ smp_s1(tfm, smp->tk, smp->rrnd, smp->prnd, stk);
memset(stk + smp->enc_key_size, 0,
SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
@@ -453,23 +533,20 @@ static void random_work(struct work_struct *work)
hci_le_start_enc(hcon, ediv, rand, stk);
hcon->enc_key_size = smp->enc_key_size;
} else {
- u8 stk[16], r[16], rand[8];
- __le16 ediv;
-
- memset(rand, 0, sizeof(rand));
- ediv = 0;
+ u8 stk[16];
+ __le64 rand = 0;
+ __le16 ediv = 0;
- swap128(smp->prnd, r);
- smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r);
+ smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
+ smp->prnd);
- smp_s1(tfm, smp->tk, smp->prnd, smp->rrnd, key);
- swap128(key, stk);
+ smp_s1(tfm, smp->tk, smp->prnd, smp->rrnd, stk);
memset(stk + smp->enc_key_size, 0,
SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
- HCI_SMP_STK_SLAVE, 0, 0, stk, smp->enc_key_size,
+ HCI_SMP_STK_SLAVE, 0, stk, smp->enc_key_size,
ediv, rand);
}
@@ -502,11 +579,33 @@ static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
void smp_chan_destroy(struct l2cap_conn *conn)
{
struct smp_chan *smp = conn->smp_chan;
+ bool complete;
BUG_ON(!smp);
- if (smp->tfm)
- crypto_free_blkcipher(smp->tfm);
+ complete = test_bit(SMP_FLAG_COMPLETE, &smp->smp_flags);
+ mgmt_smp_complete(conn->hcon, complete);
+
+ kfree(smp->csrk);
+ kfree(smp->slave_csrk);
+
+ /* If pairing failed clean up any keys we might have */
+ if (!complete) {
+ if (smp->ltk) {
+ list_del(&smp->ltk->list);
+ kfree(smp->ltk);
+ }
+
+ if (smp->slave_ltk) {
+ list_del(&smp->slave_ltk->list);
+ kfree(smp->slave_ltk);
+ }
+
+ if (smp->remote_irk) {
+ list_del(&smp->remote_irk->list);
+ kfree(smp->remote_irk);
+ }
+ }
kfree(smp);
conn->smp_chan = NULL;
@@ -519,7 +618,6 @@ int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
struct l2cap_conn *conn = hcon->smp_conn;
struct smp_chan *smp;
u32 value;
- u8 key[16];
BT_DBG("");
@@ -531,10 +629,9 @@ int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
switch (mgmt_op) {
case MGMT_OP_USER_PASSKEY_REPLY:
value = le32_to_cpu(passkey);
- memset(key, 0, sizeof(key));
+ memset(smp->tk, 0, sizeof(smp->tk));
BT_DBG("PassKey: %d", value);
- put_unaligned_le32(value, key);
- swap128(key, smp->tk);
+ put_unaligned_le32(value, smp->tk);
/* Fall Through */
case MGMT_OP_USER_CONFIRM_REPLY:
set_bit(SMP_FLAG_TK_VALID, &smp->smp_flags);
@@ -565,6 +662,9 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
BT_DBG("conn %p", conn);
+ if (skb->len < sizeof(*req))
+ return SMP_UNSPECIFIED;
+
if (conn->hcon->link_mode & HCI_LM_MASTER)
return SMP_CMD_NOTSUPP;
@@ -604,6 +704,8 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
if (ret)
return SMP_UNSPECIFIED;
+ clear_bit(SMP_FLAG_INITIATOR, &smp->smp_flags);
+
return 0;
}
@@ -617,6 +719,9 @@ static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
BT_DBG("conn %p", conn);
+ if (skb->len < sizeof(*rsp))
+ return SMP_UNSPECIFIED;
+
if (!(conn->hcon->link_mode & HCI_LM_MASTER))
return SMP_CMD_NOTSUPP;
@@ -633,6 +738,11 @@ static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
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_BONDING) &&
(rsp->auth_req & SMP_AUTH_BONDING))
auth = SMP_AUTH_BONDING;
@@ -646,10 +756,8 @@ static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
set_bit(SMP_FLAG_CFM_PENDING, &smp->smp_flags);
/* Can't compose response until we have been confirmed */
- if (!test_bit(SMP_FLAG_TK_VALID, &smp->smp_flags))
- return 0;
-
- queue_work(hdev->workqueue, &smp->confirm);
+ if (test_bit(SMP_FLAG_TK_VALID, &smp->smp_flags))
+ queue_work(hdev->workqueue, &smp->confirm);
return 0;
}
@@ -661,20 +769,19 @@ static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
+ if (skb->len < sizeof(smp->pcnf))
+ return SMP_UNSPECIFIED;
+
memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
skb_pull(skb, sizeof(smp->pcnf));
- if (conn->hcon->out) {
- u8 random[16];
-
- swap128(smp->prnd, random);
- smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random),
- random);
- } else if (test_bit(SMP_FLAG_TK_VALID, &smp->smp_flags)) {
+ if (conn->hcon->out)
+ smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
+ smp->prnd);
+ else if (test_bit(SMP_FLAG_TK_VALID, &smp->smp_flags))
queue_work(hdev->workqueue, &smp->confirm);
- } else {
+ else
set_bit(SMP_FLAG_CFM_PENDING, &smp->smp_flags);
- }
return 0;
}
@@ -686,7 +793,10 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
BT_DBG("conn %p", conn);
- swap128(skb->data, smp->rrnd);
+ if (skb->len < sizeof(smp->rrnd))
+ return SMP_UNSPECIFIED;
+
+ memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
skb_pull(skb, sizeof(smp->rrnd));
queue_work(hdev->workqueue, &smp->random);
@@ -699,7 +809,8 @@ static u8 smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
struct smp_ltk *key;
struct hci_conn *hcon = conn->hcon;
- key = hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type);
+ key = hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type,
+ hcon->out);
if (!key)
return 0;
@@ -724,6 +835,9 @@ static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
BT_DBG("conn %p", conn);
+ if (skb->len < sizeof(*rp))
+ return SMP_UNSPECIFIED;
+
if (!(conn->hcon->link_mode & HCI_LM_MASTER))
return SMP_CMD_NOTSUPP;
@@ -747,6 +861,8 @@ static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
+ clear_bit(SMP_FLAG_INITIATOR, &smp->smp_flags);
+
return 0;
}
@@ -764,11 +880,15 @@ bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level)
int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
{
struct l2cap_conn *conn = hcon->l2cap_data;
- struct smp_chan *smp = conn->smp_chan;
+ struct smp_chan *smp;
__u8 authreq;
BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
+ /* This may be NULL if there's an unexpected disconnection */
+ if (!conn)
+ return 1;
+
if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags))
return 1;
@@ -788,6 +908,12 @@ int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
authreq = seclevel_to_authreq(sec_level);
+ /* hcon->auth_type is set by pair_device in mgmt.c. If the MITM
+ * flag is set we should also set it for the SMP request.
+ */
+ if ((hcon->auth_type & 0x01))
+ authreq |= SMP_AUTH_MITM;
+
if (hcon->link_mode & HCI_LM_MASTER) {
struct smp_cmd_pairing cp;
@@ -802,6 +928,8 @@ int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
}
+ set_bit(SMP_FLAG_INITIATOR, &smp->smp_flags);
+
done:
hcon->pending_sec_level = sec_level;
@@ -813,6 +941,15 @@ static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
struct smp_cmd_encrypt_info *rp = (void *) skb->data;
struct smp_chan *smp = conn->smp_chan;
+ BT_DBG("conn %p", conn);
+
+ if (skb->len < sizeof(*rp))
+ return SMP_UNSPECIFIED;
+
+ /* Ignore this PDU if it wasn't requested */
+ if (!(smp->remote_key_dist & SMP_DIST_ENC_KEY))
+ return 0;
+
skb_pull(skb, sizeof(*rp));
memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
@@ -826,16 +963,138 @@ static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
struct smp_chan *smp = conn->smp_chan;
struct hci_dev *hdev = conn->hcon->hdev;
struct hci_conn *hcon = conn->hcon;
+ struct smp_ltk *ltk;
u8 authenticated;
+ BT_DBG("conn %p", conn);
+
+ if (skb->len < sizeof(*rp))
+ return SMP_UNSPECIFIED;
+
+ /* Ignore this PDU if it wasn't requested */
+ if (!(smp->remote_key_dist & SMP_DIST_ENC_KEY))
+ return 0;
+
+ /* Mark the information as received */
+ smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
+
skb_pull(skb, sizeof(*rp));
hci_dev_lock(hdev);
authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
- hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, HCI_SMP_LTK, 1,
- authenticated, smp->tk, smp->enc_key_size,
- rp->ediv, rp->rand);
- smp_distribute_keys(conn, 1);
+ ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, HCI_SMP_LTK,
+ authenticated, smp->tk, smp->enc_key_size,
+ rp->ediv, rp->rand);
+ smp->ltk = ltk;
+ if (!(smp->remote_key_dist & SMP_DIST_ID_KEY))
+ smp_distribute_keys(conn);
+ hci_dev_unlock(hdev);
+
+ 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 smp_chan *smp = conn->smp_chan;
+
+ BT_DBG("");
+
+ if (skb->len < sizeof(*info))
+ return SMP_UNSPECIFIED;
+
+ /* Ignore this PDU if it wasn't requested */
+ if (!(smp->remote_key_dist & SMP_DIST_ID_KEY))
+ return 0;
+
+ 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 smp_chan *smp = conn->smp_chan;
+ struct hci_conn *hcon = conn->hcon;
+ bdaddr_t rpa;
+
+ BT_DBG("");
+
+ if (skb->len < sizeof(*info))
+ return SMP_UNSPECIFIED;
+
+ /* Ignore this PDU if it wasn't requested */
+ if (!(smp->remote_key_dist & SMP_DIST_ID_KEY))
+ return 0;
+
+ /* Mark the information as received */
+ smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
+
+ skb_pull(skb, sizeof(*info));
+
+ /* Strictly speaking the Core Specification (4.1) allows sending
+ * an empty address which would force us to rely on just the IRK
+ * as "identity information". However, since such
+ * implementations are not known of and in order to not over
+ * complicate our implementation, simply pretend that we never
+ * received an IRK for such a device.
+ */
+ if (!bacmp(&info->bdaddr, BDADDR_ANY)) {
+ BT_ERR("Ignoring IRK with no identity address");
+ smp_distribute_keys(conn);
+ return 0;
+ }
+
+ 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);
+
+ smp_distribute_keys(conn);
+
+ 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 smp_chan *smp = conn->smp_chan;
+ struct hci_dev *hdev = conn->hcon->hdev;
+ struct smp_csrk *csrk;
+
+ BT_DBG("conn %p", conn);
+
+ if (skb->len < sizeof(*rp))
+ return SMP_UNSPECIFIED;
+
+ /* Ignore this PDU if it wasn't requested */
+ if (!(smp->remote_key_dist & SMP_DIST_SIGN))
+ return 0;
+
+ /* Mark the information as received */
+ smp->remote_key_dist &= ~SMP_DIST_SIGN;
+
+ skb_pull(skb, sizeof(*rp));
+
+ hci_dev_lock(hdev);
+ csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
+ if (csrk) {
+ csrk->master = 0x01;
+ memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
+ }
+ smp->csrk = csrk;
+ if (!(smp->remote_key_dist & SMP_DIST_SIGN))
+ smp_distribute_keys(conn);
hci_dev_unlock(hdev);
return 0;
@@ -915,10 +1174,15 @@ int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *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:
- /* Just ignored */
- reason = 0;
+ reason = smp_cmd_sign_info(conn, skb);
break;
default:
@@ -937,26 +1201,78 @@ done:
return err;
}
-int smp_distribute_keys(struct l2cap_conn *conn, __u8 force)
+static void smp_notify_keys(struct l2cap_conn *conn)
+{
+ struct smp_chan *smp = conn->smp_chan;
+ struct hci_conn *hcon = conn->hcon;
+ struct hci_dev *hdev = hcon->hdev;
+ struct smp_cmd_pairing *req = (void *) &smp->preq[1];
+ struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
+ bool persistent;
+
+ if (smp->remote_irk) {
+ mgmt_new_irk(hdev, smp->remote_irk);
+ /* Now that user space can be considered to know the
+ * identity address track the connection based on it
+ * from now on.
+ */
+ bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
+ hcon->dst_type = smp->remote_irk->addr_type;
+ l2cap_conn_update_id_addr(hcon);
+ }
+
+ /* The LTKs and CSRKs should be persistent only if both sides
+ * had the bonding bit set in their authentication requests.
+ */
+ persistent = !!((req->auth_req & rsp->auth_req) & SMP_AUTH_BONDING);
+
+ if (smp->csrk) {
+ smp->csrk->bdaddr_type = hcon->dst_type;
+ bacpy(&smp->csrk->bdaddr, &hcon->dst);
+ mgmt_new_csrk(hdev, smp->csrk, persistent);
+ }
+
+ if (smp->slave_csrk) {
+ smp->slave_csrk->bdaddr_type = hcon->dst_type;
+ bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
+ mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
+ }
+
+ if (smp->ltk) {
+ smp->ltk->bdaddr_type = hcon->dst_type;
+ bacpy(&smp->ltk->bdaddr, &hcon->dst);
+ mgmt_new_ltk(hdev, smp->ltk, persistent);
+ }
+
+ if (smp->slave_ltk) {
+ smp->slave_ltk->bdaddr_type = hcon->dst_type;
+ bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
+ mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
+ }
+}
+
+int smp_distribute_keys(struct l2cap_conn *conn)
{
struct smp_cmd_pairing *req, *rsp;
struct smp_chan *smp = conn->smp_chan;
+ struct hci_conn *hcon = conn->hcon;
+ struct hci_dev *hdev = hcon->hdev;
__u8 *keydist;
- BT_DBG("conn %p force %d", conn, force);
+ BT_DBG("conn %p", conn);
- if (!test_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags))
+ if (!test_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags))
return 0;
rsp = (void *) &smp->prsp[1];
/* The responder sends its keys first */
- if (!force && conn->hcon->out && (rsp->resp_key_dist & 0x07))
+ if (hcon->out && (smp->remote_key_dist & 0x07))
return 0;
req = (void *) &smp->preq[1];
- if (conn->hcon->out) {
+ if (hcon->out) {
keydist = &rsp->init_key_dist;
*keydist &= req->init_key_dist;
} else {
@@ -964,28 +1280,30 @@ int smp_distribute_keys(struct l2cap_conn *conn, __u8 force)
*keydist &= req->resp_key_dist;
}
-
BT_DBG("keydist 0x%x", *keydist);
if (*keydist & SMP_DIST_ENC_KEY) {
struct smp_cmd_encrypt_info enc;
struct smp_cmd_master_ident ident;
- struct hci_conn *hcon = conn->hcon;
+ struct smp_ltk *ltk;
u8 authenticated;
__le16 ediv;
+ __le64 rand;
get_random_bytes(enc.ltk, sizeof(enc.ltk));
get_random_bytes(&ediv, sizeof(ediv));
- get_random_bytes(ident.rand, sizeof(ident.rand));
+ get_random_bytes(&rand, sizeof(rand));
smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
authenticated = hcon->sec_level == BT_SECURITY_HIGH;
- hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
- HCI_SMP_LTK_SLAVE, 1, authenticated,
- enc.ltk, smp->enc_key_size, ediv, ident.rand);
+ ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
+ HCI_SMP_LTK_SLAVE, authenticated, enc.ltk,
+ smp->enc_key_size, ediv, rand);
+ smp->slave_ltk = ltk;
ident.ediv = ediv;
+ ident.rand = rand;
smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
@@ -996,14 +1314,18 @@ int smp_distribute_keys(struct l2cap_conn *conn, __u8 force)
struct smp_cmd_ident_addr_info addrinfo;
struct smp_cmd_ident_info idinfo;
- /* Send a dummy key */
- get_random_bytes(idinfo.irk, sizeof(idinfo.irk));
+ memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
- /* Just public address */
- memset(&addrinfo, 0, sizeof(addrinfo));
- bacpy(&addrinfo.bdaddr, &conn->hcon->src);
+ /* 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);
@@ -1013,20 +1335,33 @@ int smp_distribute_keys(struct l2cap_conn *conn, __u8 force)
if (*keydist & SMP_DIST_SIGN) {
struct smp_cmd_sign_info sign;
+ struct smp_csrk *csrk;
- /* Send a dummy key */
+ /* Generate a new random key */
get_random_bytes(sign.csrk, sizeof(sign.csrk));
+ csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
+ if (csrk) {
+ csrk->master = 0x00;
+ memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
+ }
+ smp->slave_csrk = csrk;
+
smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
*keydist &= ~SMP_DIST_SIGN;
}
- if (conn->hcon->out || force) {
- clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags);
- cancel_delayed_work_sync(&conn->security_timer);
- smp_chan_destroy(conn);
- }
+ /* If there are still keys to be received wait for them */
+ if ((smp->remote_key_dist & 0x07))
+ return 0;
+
+ clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags);
+ cancel_delayed_work_sync(&conn->security_timer);
+ set_bit(SMP_FLAG_COMPLETE, &smp->smp_flags);
+ smp_notify_keys(conn);
+
+ smp_chan_destroy(conn);
return 0;
}