| /* |
| 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 <net/bluetooth/bluetooth.h> |
| #include <net/bluetooth/hci_core.h> |
| #include <net/bluetooth/l2cap.h> |
| #include <net/bluetooth/smp.h> |
| #include <linux/crypto.h> |
| #include <linux/scatterlist.h> |
| #include <crypto/b128ops.h> |
| |
| #define SMP_TIMEOUT 30000 /* 30 seconds */ |
| |
| static inline void swap128(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]) |
| { |
| int i; |
| for (i = 0; i < 7; i++) |
| dst[6 - i] = src[i]; |
| } |
| |
| static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r) |
| { |
| struct blkcipher_desc desc; |
| struct scatterlist sg; |
| int err, iv_len; |
| unsigned char iv[128]; |
| |
| if (tfm == NULL) { |
| BT_ERR("tfm %p", tfm); |
| return -EINVAL; |
| } |
| |
| desc.tfm = tfm; |
| desc.flags = 0; |
| |
| err = crypto_blkcipher_setkey(tfm, k, 16); |
| if (err) { |
| BT_ERR("cipher setkey failed: %d", err); |
| return err; |
| } |
| |
| sg_init_one(&sg, r, 16); |
| |
| iv_len = crypto_blkcipher_ivsize(tfm); |
| if (iv_len) { |
| memset(&iv, 0xff, iv_len); |
| crypto_blkcipher_set_iv(tfm, iv, iv_len); |
| } |
| |
| err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16); |
| if (err) |
| BT_ERR("Encrypt data error %d", err); |
| |
| return err; |
| } |
| |
| 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]) |
| { |
| u8 p1[16], p2[16]; |
| int err; |
| |
| 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); |
| |
| /* p2 = padding || ia || ra */ |
| baswap((bdaddr_t *) (p2 + 4), ia); |
| baswap((bdaddr_t *) (p2 + 10), ra); |
| |
| /* res = r XOR p1 */ |
| u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); |
| |
| /* res = e(k, res) */ |
| err = smp_e(tfm, k, res); |
| if (err) { |
| BT_ERR("Encrypt data error"); |
| return err; |
| } |
| |
| /* res = res XOR p2 */ |
| u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); |
| |
| /* res = e(k, res) */ |
| err = smp_e(tfm, k, res); |
| if (err) |
| BT_ERR("Encrypt data error"); |
| |
| return err; |
| } |
| |
| static int smp_s1(struct crypto_blkcipher *tfm, u8 k[16], |
| u8 r1[16], u8 r2[16], u8 _r[16]) |
| { |
| int err; |
| |
| /* Just least significant octets from r1 and r2 are considered */ |
| memcpy(_r, r1 + 8, 8); |
| memcpy(_r + 8, r2 + 8, 8); |
| |
| err = smp_e(tfm, k, _r); |
| if (err) |
| BT_ERR("Encrypt data error"); |
| |
| return err; |
| } |
| |
| static int smp_rand(u8 *buf) |
| { |
| get_random_bytes(buf, 16); |
| |
| return 0; |
| } |
| |
| static struct sk_buff *smp_build_cmd(struct l2cap_conn *conn, u8 code, |
| u16 dlen, void *data) |
| { |
| struct sk_buff *skb; |
| struct l2cap_hdr *lh; |
| int len; |
| |
| len = L2CAP_HDR_SIZE + sizeof(code) + dlen; |
| |
| if (len > conn->mtu) |
| return NULL; |
| |
| skb = bt_skb_alloc(len, GFP_ATOMIC); |
| if (!skb) |
| return NULL; |
| |
| lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE); |
| lh->len = cpu_to_le16(sizeof(code) + dlen); |
| lh->cid = cpu_to_le16(L2CAP_CID_SMP); |
| |
| memcpy(skb_put(skb, sizeof(code)), &code, sizeof(code)); |
| |
| memcpy(skb_put(skb, dlen), data, dlen); |
| |
| return skb; |
| } |
| |
| static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) |
| { |
| struct sk_buff *skb = smp_build_cmd(conn, code, len, data); |
| |
| BT_DBG("code 0x%2.2x", code); |
| |
| if (!skb) |
| return; |
| |
| skb->priority = HCI_PRIO_MAX; |
| hci_send_acl(conn->hchan, skb, 0); |
| |
| mod_timer(&conn->security_timer, jiffies + |
| msecs_to_jiffies(SMP_TIMEOUT)); |
| } |
| |
| static void build_pairing_cmd(struct l2cap_conn *conn, |
| struct smp_cmd_pairing *req, |
| struct smp_cmd_pairing *rsp, |
| __u8 authreq) |
| { |
| u8 dist_keys; |
| |
| dist_keys = 0; |
| if (test_bit(HCI_PAIRABLE, &conn->hcon->hdev->flags)) { |
| dist_keys = SMP_DIST_ENC_KEY; |
| authreq |= SMP_AUTH_BONDING; |
| } |
| |
| 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 = dist_keys; |
| req->resp_key_dist = dist_keys; |
| req->auth_req = authreq; |
| return; |
| } |
| |
| rsp->io_capability = conn->hcon->io_capability; |
| rsp->oob_flag = SMP_OOB_NOT_PRESENT; |
| rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE; |
| rsp->init_key_dist = req->init_key_dist & dist_keys; |
| rsp->resp_key_dist = req->resp_key_dist & dist_keys; |
| rsp->auth_req = authreq; |
| } |
| |
| static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) |
| { |
| struct smp_chan *smp = conn->smp_chan; |
| |
| if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) || |
| (max_key_size < SMP_MIN_ENC_KEY_SIZE)) |
| return SMP_ENC_KEY_SIZE; |
| |
| smp->smp_key_size = max_key_size; |
| |
| return 0; |
| } |
| |
| 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 smp_cmd_pairing_confirm cp; |
| int ret; |
| u8 res[16], 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; |
| } |
| |
| smp->tfm = tfm; |
| |
| if (conn->hcon->out) |
| ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, 0, |
| conn->src, conn->hcon->dst_type, conn->dst, |
| res); |
| else |
| ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, |
| conn->hcon->dst_type, conn->dst, 0, conn->src, |
| res); |
| if (ret) { |
| reason = SMP_UNSPECIFIED; |
| goto error; |
| } |
| |
| swap128(res, cp.confirm_val); |
| smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); |
| |
| return; |
| |
| error: |
| smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), &reason); |
| smp_chan_destroy(conn); |
| } |
| |
| 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]; |
| int ret; |
| |
| if (IS_ERR_OR_NULL(tfm)) { |
| reason = SMP_UNSPECIFIED; |
| goto error; |
| } |
| |
| 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, 0, |
| conn->src, hcon->dst_type, conn->dst, |
| res); |
| else |
| ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp, |
| hcon->dst_type, conn->dst, 0, conn->src, |
| res); |
| 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; |
| goto error; |
| } |
| |
| if (hcon->out) { |
| u8 stk[16], rand[8]; |
| __le16 ediv; |
| |
| memset(rand, 0, sizeof(rand)); |
| ediv = 0; |
| |
| smp_s1(tfm, smp->tk, smp->rrnd, smp->prnd, key); |
| swap128(key, stk); |
| |
| memset(stk + smp->smp_key_size, 0, |
| SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size); |
| |
| if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend)) { |
| reason = SMP_UNSPECIFIED; |
| goto error; |
| } |
| |
| hci_le_start_enc(hcon, ediv, rand, stk); |
| hcon->enc_key_size = smp->smp_key_size; |
| } else { |
| u8 stk[16], r[16], rand[8]; |
| __le16 ediv; |
| |
| memset(rand, 0, sizeof(rand)); |
| ediv = 0; |
| |
| swap128(smp->prnd, r); |
| smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r); |
| |
| smp_s1(tfm, smp->tk, smp->prnd, smp->rrnd, key); |
| swap128(key, stk); |
| |
| memset(stk + smp->smp_key_size, 0, |
| SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size); |
| |
| hci_add_ltk(hcon->hdev, 0, conn->dst, smp->smp_key_size, |
| ediv, rand, stk); |
| } |
| |
| return; |
| |
| error: |
| smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), &reason); |
| smp_chan_destroy(conn); |
| } |
| |
| static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) |
| { |
| struct smp_chan *smp; |
| |
| smp = kzalloc(sizeof(struct smp_chan), GFP_ATOMIC); |
| if (!smp) |
| return NULL; |
| |
| INIT_WORK(&smp->confirm, confirm_work); |
| INIT_WORK(&smp->random, random_work); |
| |
| smp->conn = conn; |
| conn->smp_chan = smp; |
| |
| hci_conn_hold(conn->hcon); |
| |
| return smp; |
| } |
| |
| void smp_chan_destroy(struct l2cap_conn *conn) |
| { |
| struct smp_chan *smp = conn->smp_chan; |
| |
| clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend); |
| |
| if (smp->tfm) |
| crypto_free_blkcipher(smp->tfm); |
| |
| kfree(smp); |
| conn->smp_chan = NULL; |
| hci_conn_put(conn->hcon); |
| } |
| |
| static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) |
| { |
| struct smp_cmd_pairing rsp, *req = (void *) skb->data; |
| struct smp_chan *smp; |
| u8 key_size; |
| int ret; |
| |
| BT_DBG("conn %p", conn); |
| |
| if (!test_and_set_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend)) |
| smp = smp_chan_create(conn); |
| |
| smp = conn->smp_chan; |
| |
| smp->preq[0] = SMP_CMD_PAIRING_REQ; |
| memcpy(&smp->preq[1], req, sizeof(*req)); |
| skb_pull(skb, sizeof(*req)); |
| |
| if (req->oob_flag) |
| return SMP_OOB_NOT_AVAIL; |
| |
| /* We didn't start the pairing, so no requirements */ |
| build_pairing_cmd(conn, req, &rsp, SMP_AUTH_NONE); |
| |
| key_size = min(req->max_key_size, rsp.max_key_size); |
| if (check_enc_key_size(conn, key_size)) |
| return SMP_ENC_KEY_SIZE; |
| |
| /* Just works */ |
| memset(smp->tk, 0, sizeof(smp->tk)); |
| |
| ret = smp_rand(smp->prnd); |
| if (ret) |
| return SMP_UNSPECIFIED; |
| |
| 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); |
| |
| 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 smp_chan *smp = conn->smp_chan; |
| struct hci_dev *hdev = conn->hcon->hdev; |
| u8 key_size; |
| int ret; |
| |
| BT_DBG("conn %p", conn); |
| |
| 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; |
| |
| if (rsp->oob_flag) |
| return SMP_OOB_NOT_AVAIL; |
| |
| /* Just works */ |
| memset(smp->tk, 0, sizeof(smp->tk)); |
| |
| ret = smp_rand(smp->prnd); |
| if (ret) |
| return SMP_UNSPECIFIED; |
| |
| smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
| memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); |
| |
| queue_work(hdev->workqueue, &smp->confirm); |
| |
| return 0; |
| } |
| |
| static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) |
| { |
| struct smp_chan *smp = conn->smp_chan; |
| struct hci_dev *hdev = conn->hcon->hdev; |
| |
| BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); |
| |
| 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 { |
| queue_work(hdev->workqueue, &smp->confirm); |
| } |
| |
| return 0; |
| } |
| |
| static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) |
| { |
| struct smp_chan *smp = conn->smp_chan; |
| struct hci_dev *hdev = conn->hcon->hdev; |
| |
| BT_DBG("conn %p", conn); |
| |
| swap128(skb->data, smp->rrnd); |
| skb_pull(skb, sizeof(smp->rrnd)); |
| |
| queue_work(hdev->workqueue, &smp->random); |
| |
| return 0; |
| } |
| |
| static u8 smp_ltk_encrypt(struct l2cap_conn *conn) |
| { |
| struct link_key *key; |
| struct key_master_id *master; |
| struct hci_conn *hcon = conn->hcon; |
| |
| key = hci_find_link_key_type(hcon->hdev, conn->dst, |
| HCI_LK_SMP_LTK); |
| if (!key) |
| return 0; |
| |
| if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, |
| &hcon->pend)) |
| return 1; |
| |
| master = (void *) key->data; |
| hci_le_start_enc(hcon, master->ediv, master->rand, |
| key->val); |
| hcon->enc_key_size = key->pin_len; |
| |
| return 1; |
| |
| } |
| static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) |
| { |
| struct smp_cmd_security_req *rp = (void *) skb->data; |
| struct smp_cmd_pairing cp; |
| struct hci_conn *hcon = conn->hcon; |
| struct smp_chan *smp; |
| |
| BT_DBG("conn %p", conn); |
| |
| hcon->pending_sec_level = BT_SECURITY_MEDIUM; |
| |
| if (smp_ltk_encrypt(conn)) |
| return 0; |
| |
| if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend)) |
| return 0; |
| |
| smp = smp_chan_create(conn); |
| |
| skb_pull(skb, sizeof(*rp)); |
| |
| memset(&cp, 0, sizeof(cp)); |
| build_pairing_cmd(conn, &cp, NULL, rp->auth_req); |
| |
| smp->preq[0] = SMP_CMD_PAIRING_REQ; |
| memcpy(&smp->preq[1], &cp, sizeof(cp)); |
| |
| smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
| |
| return 0; |
| } |
| |
| int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level) |
| { |
| struct hci_conn *hcon = conn->hcon; |
| struct smp_chan *smp = conn->smp_chan; |
| |
| BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); |
| |
| if (!lmp_host_le_capable(hcon->hdev)) |
| return 1; |
| |
| if (sec_level == BT_SECURITY_LOW) |
| return 1; |
| |
| if (hcon->sec_level >= sec_level) |
| return 1; |
| |
| if (hcon->link_mode & HCI_LM_MASTER) |
| if (smp_ltk_encrypt(conn)) |
| goto done; |
| |
| if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend)) |
| return 0; |
| |
| smp = smp_chan_create(conn); |
| |
| if (hcon->link_mode & HCI_LM_MASTER) { |
| struct smp_cmd_pairing cp; |
| |
| build_pairing_cmd(conn, &cp, NULL, SMP_AUTH_NONE); |
| smp->preq[0] = SMP_CMD_PAIRING_REQ; |
| memcpy(&smp->preq[1], &cp, sizeof(cp)); |
| |
| smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
| } else { |
| struct smp_cmd_security_req cp; |
| cp.auth_req = SMP_AUTH_NONE; |
| smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); |
| } |
| |
| done: |
| hcon->pending_sec_level = sec_level; |
| |
| return 0; |
| } |
| |
| 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; |
| |
| skb_pull(skb, sizeof(*rp)); |
| |
| memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); |
| |
| return 0; |
| } |
| |
| static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) |
| { |
| struct smp_cmd_master_ident *rp = (void *) skb->data; |
| struct smp_chan *smp = conn->smp_chan; |
| |
| skb_pull(skb, sizeof(*rp)); |
| |
| hci_add_ltk(conn->hcon->hdev, 1, conn->src, smp->smp_key_size, |
| rp->ediv, rp->rand, smp->tk); |
| |
| smp_distribute_keys(conn, 1); |
| |
| return 0; |
| } |
| |
| int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb) |
| { |
| __u8 code = skb->data[0]; |
| __u8 reason; |
| int err = 0; |
| |
| if (!lmp_host_le_capable(conn->hcon->hdev)) { |
| err = -ENOTSUPP; |
| reason = SMP_PAIRING_NOTSUPP; |
| goto done; |
| } |
| |
| skb_pull(skb, sizeof(code)); |
| |
| switch (code) { |
| case SMP_CMD_PAIRING_REQ: |
| reason = smp_cmd_pairing_req(conn, skb); |
| break; |
| |
| case SMP_CMD_PAIRING_FAIL: |
| reason = 0; |
| err = -EPERM; |
| break; |
| |
| case SMP_CMD_PAIRING_RSP: |
| reason = smp_cmd_pairing_rsp(conn, skb); |
| break; |
| |
| case SMP_CMD_SECURITY_REQ: |
| reason = smp_cmd_security_req(conn, skb); |
| break; |
| |
| case SMP_CMD_PAIRING_CONFIRM: |
| reason = smp_cmd_pairing_confirm(conn, skb); |
| break; |
| |
| case SMP_CMD_PAIRING_RANDOM: |
| reason = smp_cmd_pairing_random(conn, skb); |
| break; |
| |
| case SMP_CMD_ENCRYPT_INFO: |
| reason = smp_cmd_encrypt_info(conn, skb); |
| break; |
| |
| case SMP_CMD_MASTER_IDENT: |
| reason = smp_cmd_master_ident(conn, skb); |
| break; |
| |
| case SMP_CMD_IDENT_INFO: |
| case SMP_CMD_IDENT_ADDR_INFO: |
| case SMP_CMD_SIGN_INFO: |
| /* Just ignored */ |
| reason = 0; |
| break; |
| |
| default: |
| BT_DBG("Unknown command code 0x%2.2x", code); |
| |
| reason = SMP_CMD_NOTSUPP; |
| err = -EOPNOTSUPP; |
| goto done; |
| } |
| |
| done: |
| if (reason) |
| smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), |
| &reason); |
| |
| kfree_skb(skb); |
| return err; |
| } |
| |
| int smp_distribute_keys(struct l2cap_conn *conn, __u8 force) |
| { |
| struct smp_cmd_pairing *req, *rsp; |
| struct smp_chan *smp = conn->smp_chan; |
| __u8 *keydist; |
| |
| BT_DBG("conn %p force %d", conn, force); |
| |
| if (!test_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend)) |
| return 0; |
| |
| rsp = (void *) &smp->prsp[1]; |
| |
| /* The responder sends its keys first */ |
| if (!force && conn->hcon->out && (rsp->resp_key_dist & 0x07)) |
| return 0; |
| |
| req = (void *) &smp->preq[1]; |
| |
| if (conn->hcon->out) { |
| keydist = &rsp->init_key_dist; |
| *keydist &= req->init_key_dist; |
| } else { |
| keydist = &rsp->resp_key_dist; |
| *keydist &= req->resp_key_dist; |
| } |
| |
| |
| BT_DBG("keydist 0x%x", *keydist); |
| |
| if (*keydist & SMP_DIST_ENC_KEY) { |
| struct smp_cmd_encrypt_info enc; |
| struct smp_cmd_master_ident ident; |
| __le16 ediv; |
| |
| get_random_bytes(enc.ltk, sizeof(enc.ltk)); |
| get_random_bytes(&ediv, sizeof(ediv)); |
| get_random_bytes(ident.rand, sizeof(ident.rand)); |
| |
| smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); |
| |
| hci_add_ltk(conn->hcon->hdev, 1, conn->dst, smp->smp_key_size, |
| ediv, ident.rand, enc.ltk); |
| |
| ident.ediv = cpu_to_le16(ediv); |
| |
| smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); |
| |
| *keydist &= ~SMP_DIST_ENC_KEY; |
| } |
| |
| if (*keydist & SMP_DIST_ID_KEY) { |
| struct smp_cmd_ident_addr_info addrinfo; |
| struct smp_cmd_ident_info idinfo; |
| |
| /* Send a dummy key */ |
| get_random_bytes(idinfo.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->src); |
| |
| 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; |
| |
| /* Send a dummy key */ |
| get_random_bytes(sign.csrk, sizeof(sign.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->pend); |
| del_timer(&conn->security_timer); |
| smp_chan_destroy(conn); |
| } |
| |
| return 0; |
| } |