SMP_FLAG_DEBUG_KEY,
SMP_FLAG_WAIT_USER,
SMP_FLAG_DHKEY_PENDING,
- SMP_FLAG_OOB,
+ SMP_FLAG_REMOTE_OOB,
+ SMP_FLAG_LOCAL_OOB,
+};
+
+struct smp_dev {
+ /* Secure Connections OOB data */
+ u8 local_pk[64];
+ u8 local_sk[32];
+ u8 local_rand[16];
+ bool debug_key;
+
+ struct crypto_blkcipher *tfm_aes;
+ struct crypto_hash *tfm_cmac;
};
struct smp_chan {
u8 rrnd[16]; /* SMP Pairing Random (remote) */
u8 pcnf[16]; /* SMP Pairing Confirm */
u8 tk[16]; /* SMP Temporary Key */
- u8 rr[16];
+ 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;
const bdaddr_t *bdaddr)
{
struct l2cap_chan *chan = hdev->smp_data;
- struct crypto_blkcipher *tfm;
+ struct smp_dev *smp;
u8 hash[3];
int err;
if (!chan || !chan->data)
return false;
- tfm = chan->data;
+ smp = chan->data;
BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
- err = smp_ah(tfm, irk, &bdaddr->b[3], hash);
+ err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
if (err)
return false;
int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
{
struct l2cap_chan *chan = hdev->smp_data;
- struct crypto_blkcipher *tfm;
+ struct smp_dev *smp;
int err;
if (!chan || !chan->data)
return -EOPNOTSUPP;
- tfm = chan->data;
+ smp = chan->data;
get_random_bytes(&rpa->b[3], 3);
rpa->b[5] &= 0x3f; /* Clear two most significant bits */
rpa->b[5] |= 0x40; /* Set second most significant bit */
- err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);
+ err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
if (err < 0)
return err;
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_DBG("Using debug keys");
+ memcpy(smp->local_pk, debug_pk, 64);
+ memcpy(smp->local_sk, debug_sk, 32);
+ smp->debug_key = true;
+ } else {
+ while (true) {
+ /* Generate local key pair for Secure Connections */
+ if (!ecc_make_key(smp->local_pk, smp->local_sk))
+ return -EIO;
+
+ /* This is unlikely, but we need to check that
+ * we didn't accidentially generate a debug key.
+ */
+ if (memcmp(smp->local_sk, debug_sk, 32))
+ 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);
+ SMP_DBG("OOB Private Key: %32phN", smp->local_sk);
+
+ 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);
+
+ return 0;
+}
+
static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
{
struct l2cap_chan *chan = conn->smp;
oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
bdaddr_type);
if (oob_data && oob_data->present) {
- set_bit(SMP_FLAG_OOB, &smp->flags);
+ 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 {
complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
mgmt_smp_complete(hcon, complete);
- kfree(smp->csrk);
- kfree(smp->slave_csrk);
- kfree(smp->link_key);
+ kzfree(smp->csrk);
+ kzfree(smp->slave_csrk);
+ kzfree(smp->link_key);
crypto_free_blkcipher(smp->tfm_aes);
crypto_free_hash(smp->tfm_cmac);
}
chan->data = NULL;
- kfree(smp);
+ kzfree(smp);
hci_conn_drop(hcon);
}
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);
return;
if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
- kfree(smp->link_key);
+ kzfree(smp->link_key);
smp->link_key = NULL;
return;
}
if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
- kfree(smp->link_key);
+ kzfree(smp->link_key);
smp->link_key = NULL;
return;
}
smp->tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(smp->tfm_aes)) {
BT_ERR("Unable to create ECB crypto context");
- kfree(smp);
+ kzfree(smp);
return NULL;
}
if (IS_ERR(smp->tfm_cmac)) {
BT_ERR("Unable to create CMAC crypto context");
crypto_free_blkcipher(smp->tfm_aes);
- kfree(smp);
+ kzfree(smp);
return NULL;
}
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)
+ 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) &&
- !test_bit(HCI_FORCE_BREDR_SMP, &hdev->dbg_flags))
+ !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
return SMP_CROSS_TRANSP_NOT_ALLOWED;
set_bit(SMP_FLAG_SC, &smp->flags);
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 */
return 0;
}
- SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
-
/* Request setup of TK */
ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
if (ret)
BT_DBG("");
+ 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->local_sk, smp_dev->local_sk, 32);
+ 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_DBG("Using debug keys");
memcpy(smp->local_pk, debug_pk, 64);
}
}
+done:
SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
- SMP_DBG("Local Public Key Y: %32phN", &smp->local_pk[32]);
+ SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
SMP_DBG("Local Private Key: %32phN", smp->local_sk);
smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
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)
+ set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
+
smp->prsp[0] = SMP_CMD_PAIRING_RSP;
memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
BT_DBG("");
- /* Public Key exchange must happen before any other steps */
- if (!test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
- return SMP_UNSPECIFIED;
-
if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
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 slave role */
+ if (hcon->out)
+ return SMP_UNSPECIFIED;
+
+ if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
+ BT_ERR("Refusing SMP SC -> legacy fallback in SC-only mode");
+ return SMP_UNSPECIFIED;
+ }
+
+ BT_ERR("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_ERR("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;
memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
skb_pull(skb, sizeof(smp->pcnf));
- if (test_bit(SMP_FLAG_SC, &smp->flags))
- return sc_check_confirm(smp);
+ 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_ERR("Unexpected SMP Pairing Confirm");
+
+ ret = fixup_sc_false_positive(smp);
+ if (ret)
+ return ret;
+ }
if (conn->hcon->out) {
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
struct smp_cmd_pairing *local, *remote;
u8 local_mitm, remote_mitm, local_io, remote_io, method;
- if (test_bit(SMP_FLAG_OOB, &smp->flags))
+ 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
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 (memcmp(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.
*/
}
SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
- SMP_DBG("Remote Public Key Y: %32phN", &smp->remote_pk[32]);
+ SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
return SMP_UNSPECIFIED;
}
if (smp->method == REQ_OOB) {
- err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
- smp->rr, 0, cfm.confirm_val);
- if (err)
- return SMP_UNSPECIFIED;
-
- if (memcmp(cfm.confirm_val, smp->pcnf, 16))
- return SMP_CONFIRM_FAILED;
-
if (hcon->out)
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
sizeof(smp->prnd), smp->prnd);
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);
/* BR/EDR must use Secure Connections for SMP */
if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
- !test_bit(HCI_FORCE_BREDR_SMP, &hdev->dbg_flags))
+ !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
return;
/* If our LE support is not enabled don't do anything */
static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
{
struct l2cap_chan *chan;
- struct crypto_blkcipher *tfm_aes;
+ struct smp_dev *smp;
+ struct crypto_blkcipher *tfm_aes;
+ struct crypto_hash *tfm_cmac;
if (cid == L2CAP_CID_SMP_BREDR) {
- tfm_aes = NULL;
+ smp = NULL;
goto create_chan;
}
- tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0);
+ smp = kzalloc(sizeof(*smp), GFP_KERNEL);
+ if (!smp)
+ return ERR_PTR(-ENOMEM);
+
+ tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(tfm_aes)) {
- BT_ERR("Unable to create crypto context");
+ BT_ERR("Unable to create ECB crypto context");
+ kzfree(smp);
return ERR_CAST(tfm_aes);
}
+ tfm_cmac = crypto_alloc_hash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(tfm_cmac)) {
+ BT_ERR("Unable to create CMAC crypto context");
+ crypto_free_blkcipher(tfm_aes);
+ kzfree(smp);
+ return ERR_CAST(tfm_cmac);
+ }
+
+ smp->tfm_aes = tfm_aes;
+ smp->tfm_cmac = tfm_cmac;
+
create_chan:
chan = l2cap_chan_create();
if (!chan) {
- crypto_free_blkcipher(tfm_aes);
+ if (smp) {
+ crypto_free_blkcipher(smp->tfm_aes);
+ crypto_free_hash(smp->tfm_cmac);
+ kzfree(smp);
+ }
return ERR_PTR(-ENOMEM);
}
- chan->data = tfm_aes;
+ chan->data = smp;
l2cap_add_scid(chan, cid);
static void smp_del_chan(struct l2cap_chan *chan)
{
- struct crypto_blkcipher *tfm_aes;
+ struct smp_dev *smp;
BT_DBG("chan %p", chan);
- tfm_aes = chan->data;
- if (tfm_aes) {
+ smp = chan->data;
+ if (smp) {
chan->data = NULL;
- crypto_free_blkcipher(tfm_aes);
+ if (smp->tfm_aes)
+ crypto_free_blkcipher(smp->tfm_aes);
+ if (smp->tfm_cmac)
+ crypto_free_hash(smp->tfm_cmac);
+ kzfree(smp);
}
l2cap_chan_put(chan);
struct hci_dev *hdev = file->private_data;
char buf[3];
- buf[0] = test_bit(HCI_FORCE_BREDR_SMP, &hdev->dbg_flags) ? 'Y': 'N';
+ buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
buf[1] = '\n';
buf[2] = '\0';
return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
if (strtobool(buf, &enable))
return -EINVAL;
- if (enable == test_bit(HCI_FORCE_BREDR_SMP, &hdev->dbg_flags))
+ if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
return -EALREADY;
if (enable) {
smp_del_chan(chan);
}
- change_bit(HCI_FORCE_BREDR_SMP, &hdev->dbg_flags);
+ hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
return count;
}
projects / firefly-linux-kernel-4.4.55.git / blobdiff