X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?p=kvmfornfv.git;a=blobdiff_plain;f=kernel%2Fnet%2Fbluetooth%2Fsmp.c;h=4b175df35184b08b5695d966f66b129148c6c011;hp=7b815bcc8c9b53b33984716839dcfb7716ee4c9a;hb=e09b41010ba33a20a87472ee821fa407a5b8da36;hpb=f93b97fd65072de626c074dbe099a1fff05ce060 diff --git a/kernel/net/bluetooth/smp.c b/kernel/net/bluetooth/smp.c index 7b815bcc8..4b175df35 100644 --- a/kernel/net/bluetooth/smp.c +++ b/kernel/net/bluetooth/smp.c @@ -33,6 +33,9 @@ #include "ecc.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 * accidentially in dmesg, i.e. the values of the various crypto keys * and the inputs & outputs of crypto functions. @@ -81,6 +84,9 @@ struct smp_dev { u8 local_rand[16]; bool debug_key; + u8 min_key_size; + u8 max_key_size; + struct crypto_blkcipher *tfm_aes; struct crypto_hash *tfm_cmac; }; @@ -371,6 +377,8 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r) uint8_t tmp[16], data[16]; int err; + SMP_DBG("k %16phN r %16phN", k, r); + if (!tfm) { BT_ERR("tfm %p", tfm); return -EINVAL; @@ -400,6 +408,8 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r) /* Most significant octet of encryptedData corresponds to data[0] */ swap_buf(data, r, 16); + SMP_DBG("r %16phN", r); + return err; } @@ -410,6 +420,10 @@ static int smp_c1(struct crypto_blkcipher *tfm_aes, const u8 k[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 */ @@ -418,10 +432,7 @@ static int smp_c1(struct crypto_blkcipher *tfm_aes, const u8 k[16], memcpy(p1 + 2, preq, 7); memcpy(p1 + 9, pres, 7); - /* p2 = padding || ia || ra */ - memcpy(p2, ra, 6); - memcpy(p2 + 6, ia, 6); - memset(p2 + 12, 0, 4); + SMP_DBG("p1 %16phN", p1); /* res = r XOR p1 */ u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); @@ -433,6 +444,13 @@ static int smp_c1(struct crypto_blkcipher *tfm_aes, const u8 k[16], 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 */ u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); @@ -477,7 +495,7 @@ static int smp_ah(struct crypto_blkcipher *tfm, const u8 irk[16], } /* The output of the random address function ah is: - * ah(h, r) = e(k, r') mod 2^24 + * 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. @@ -696,7 +714,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn, if (rsp == NULL) { req->io_capability = conn->hcon->io_capability; req->oob_flag = oob_flag; - req->max_key_size = SMP_MAX_ENC_KEY_SIZE; + req->max_key_size = SMP_DEV(hdev)->max_key_size; req->init_key_dist = local_dist; req->resp_key_dist = remote_dist; req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); @@ -707,7 +725,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn, rsp->io_capability = conn->hcon->io_capability; rsp->oob_flag = oob_flag; - rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE; + rsp->max_key_size = SMP_DEV(hdev)->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)); @@ -718,10 +736,11 @@ static void build_pairing_cmd(struct l2cap_conn *conn, 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 ((max_key_size > SMP_MAX_ENC_KEY_SIZE) || - (max_key_size < SMP_MIN_ENC_KEY_SIZE)) + if (max_key_size > SMP_DEV(hdev)->max_key_size || + max_key_size < SMP_MIN_ENC_KEY_SIZE) return SMP_ENC_KEY_SIZE; smp->enc_key_size = max_key_size; @@ -792,7 +811,6 @@ static void smp_failure(struct l2cap_conn *conn, u8 reason) smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), &reason); - clear_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags); mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); if (chan->data) @@ -985,13 +1003,10 @@ static u8 smp_random(struct smp_chan *smp) smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk); - memset(stk + smp->enc_key_size, 0, - SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size); - if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) return SMP_UNSPECIFIED; - hci_le_start_enc(hcon, ediv, rand, stk); + 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 { @@ -1004,9 +1019,6 @@ static u8 smp_random(struct smp_chan *smp) smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk); - memset(stk + smp->enc_key_size, 0, - SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size); - if (hcon->pending_sec_level == BT_SECURITY_HIGH) auth = 1; else @@ -1033,35 +1045,6 @@ static void smp_notify_keys(struct l2cap_conn *conn) 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 (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; - queue_work(hdev->workqueue, &conn->id_addr_update_work); - } - - /* When receiving an indentity resolving key for - * a remote device that does not use a resolvable - * private address, just remove the key so that - * it is possible to use the controller white - * list for scanning. - * - * Userspace will have been told to not store - * this key at this point. So it is safe to - * just remove it. - */ - if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) { - list_del_rcu(&smp->remote_irk->list); - kfree_rcu(smp->remote_irk, rcu); - smp->remote_irk = NULL; - } - } - if (hcon->type == ACL_LINK) { if (hcon->key_type == HCI_LK_DEBUG_COMBINATION) persistent = false; @@ -1069,13 +1052,27 @@ static void smp_notify_keys(struct l2cap_conn *conn) persistent = !test_bit(HCI_CONN_FLUSH_KEY, &hcon->flags); } else { - /* The LTKs and CSRKs should be persistent only if both sides - * had the bonding bit set in their authentication requests. + /* 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; + queue_work(hdev->workqueue, &conn->id_addr_update_work); + } + } if (smp->csrk) { smp->csrk->bdaddr_type = hcon->dst_type; @@ -1144,9 +1141,6 @@ static void sc_add_ltk(struct smp_chan *smp) else auth = 0; - memset(smp->tk + smp->enc_key_size, 0, - SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size); - smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, key_type, auth, smp->tk, smp->enc_key_size, 0, 0); @@ -1268,7 +1262,14 @@ static void smp_distribute_keys(struct smp_chan *smp) __le16 ediv; __le64 rand; - get_random_bytes(enc.ltk, sizeof(enc.ltk)); + /* 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)); @@ -1688,7 +1689,7 @@ static void build_bredr_pairing_cmd(struct smp_chan *smp, req->init_key_dist = local_dist; req->resp_key_dist = remote_dist; - req->max_key_size = SMP_MAX_ENC_KEY_SIZE; + req->max_key_size = conn->hcon->enc_key_size; smp->remote_key_dist = remote_dist; @@ -1697,7 +1698,7 @@ static void build_bredr_pairing_cmd(struct smp_chan *smp, memset(rsp, 0, sizeof(*rsp)); - rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE; + 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; @@ -2190,7 +2191,7 @@ static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) return true; - hci_le_start_enc(hcon, key->ediv, key->rand, key->val); + 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 master role, so clear this flag */ @@ -2294,12 +2295,6 @@ int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) if (!conn) return 1; - chan = conn->smp; - if (!chan) { - BT_ERR("SMP security requested but not available"); - return 1; - } - if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) return 1; @@ -2313,6 +2308,12 @@ int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) return 0; + chan = conn->smp; + if (!chan) { + BT_ERR("SMP security requested but not available"); + return 1; + } + l2cap_chan_lock(chan); /* If SMP is already in progress ignore this request */ @@ -2363,6 +2364,32 @@ unlock: return ret; } +void smp_cancel_pairing(struct hci_conn *hcon) +{ + struct l2cap_conn *conn = hcon->l2cap_data; + struct l2cap_chan *chan; + struct smp_chan *smp; + + if (!conn) + return; + + chan = conn->smp; + if (!chan) + return; + + l2cap_chan_lock(chan); + + smp = chan->data; + if (smp) { + if (test_bit(SMP_FLAG_COMPLETE, &smp->flags)) + smp_failure(conn, 0); + else + smp_failure(conn, SMP_UNSPECIFIED); + } + + l2cap_chan_unlock(chan); +} + static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) { struct smp_cmd_encrypt_info *rp = (void *) skb->data; @@ -2742,7 +2769,7 @@ static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) sc_add_ltk(smp); if (hcon->out) { - hci_le_start_enc(hcon, 0, 0, smp->tk); + hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size); hcon->enc_key_size = smp->enc_key_size; } @@ -2984,8 +3011,13 @@ static void smp_ready_cb(struct l2cap_chan *chan) BT_DBG("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 wont + * get called if smp_new_conn_cb was previously called. + */ conn->smp = chan; - l2cap_chan_hold(chan); if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) bredr_pairing(chan); @@ -3124,6 +3156,8 @@ static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) smp->tfm_aes = tfm_aes; smp->tfm_cmac = tfm_cmac; + smp->min_key_size = SMP_MIN_ENC_KEY_SIZE; + smp->max_key_size = SMP_MAX_ENC_KEY_SIZE; create_chan: chan = l2cap_chan_create(); @@ -3246,6 +3280,94 @@ static const struct file_operations force_bredr_smp_fops = { .llseek = default_llseek, }; +static ssize_t le_min_key_size_read(struct file *file, + char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct hci_dev *hdev = file->private_data; + char buf[4]; + + snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size); + + return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); +} + +static ssize_t le_min_key_size_write(struct file *file, + const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct hci_dev *hdev = file->private_data; + char buf[32]; + size_t buf_size = min(count, (sizeof(buf) - 1)); + u8 key_size; + + if (copy_from_user(buf, user_buf, buf_size)) + return -EFAULT; + + buf[buf_size] = '\0'; + + sscanf(buf, "%hhu", &key_size); + + if (key_size > SMP_DEV(hdev)->max_key_size || + key_size < SMP_MIN_ENC_KEY_SIZE) + return -EINVAL; + + SMP_DEV(hdev)->min_key_size = key_size; + + return count; +} + +static const struct file_operations le_min_key_size_fops = { + .open = simple_open, + .read = le_min_key_size_read, + .write = le_min_key_size_write, + .llseek = default_llseek, +}; + +static ssize_t le_max_key_size_read(struct file *file, + char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct hci_dev *hdev = file->private_data; + char buf[4]; + + snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size); + + return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); +} + +static ssize_t le_max_key_size_write(struct file *file, + const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct hci_dev *hdev = file->private_data; + char buf[32]; + size_t buf_size = min(count, (sizeof(buf) - 1)); + u8 key_size; + + if (copy_from_user(buf, user_buf, buf_size)) + return -EFAULT; + + buf[buf_size] = '\0'; + + sscanf(buf, "%hhu", &key_size); + + if (key_size > SMP_MAX_ENC_KEY_SIZE || + key_size < SMP_DEV(hdev)->min_key_size) + return -EINVAL; + + SMP_DEV(hdev)->max_key_size = key_size; + + return count; +} + +static const struct file_operations le_max_key_size_fops = { + .open = simple_open, + .read = le_max_key_size_read, + .write = le_max_key_size_write, + .llseek = default_llseek, +}; + int smp_register(struct hci_dev *hdev) { struct l2cap_chan *chan; @@ -3270,6 +3392,11 @@ int smp_register(struct hci_dev *hdev) hdev->smp_data = chan; + debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev, + &le_min_key_size_fops); + debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev, + &le_max_key_size_fops); + /* If the controller does not support BR/EDR Secure Connections * feature, then the BR/EDR SMP channel shall not be present. *