diff options
Diffstat (limited to 'net/bluetooth/smp.c')
-rw-r--r-- | net/bluetooth/smp.c | 585 |
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; } |