diff options
Diffstat (limited to 'net/bluetooth/l2cap_core.c')
-rw-r--r-- | net/bluetooth/l2cap_core.c | 136 |
1 files changed, 97 insertions, 39 deletions
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 1fc23cb4a3e0..11012a509070 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -1340,6 +1340,21 @@ static void l2cap_request_info(struct l2cap_conn *conn) sizeof(req), &req); } +static bool l2cap_check_enc_key_size(struct hci_conn *hcon) +{ + /* The minimum encryption key size needs to be enforced by the + * host stack before establishing any L2CAP connections. The + * specification in theory allows a minimum of 1, but to align + * BR/EDR and LE transports, a minimum of 7 is chosen. + * + * This check might also be called for unencrypted connections + * that have no key size requirements. Ensure that the link is + * actually encrypted before enforcing a key size. + */ + return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) || + hcon->enc_key_size >= HCI_MIN_ENC_KEY_SIZE); +} + static void l2cap_do_start(struct l2cap_chan *chan) { struct l2cap_conn *conn = chan->conn; @@ -1357,9 +1372,14 @@ static void l2cap_do_start(struct l2cap_chan *chan) if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)) return; - if (l2cap_chan_check_security(chan, true) && - __l2cap_no_conn_pending(chan)) + if (!l2cap_chan_check_security(chan, true) || + !__l2cap_no_conn_pending(chan)) + return; + + if (l2cap_check_enc_key_size(conn->hcon)) l2cap_start_connection(chan); + else + __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); } static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask) @@ -1438,7 +1458,10 @@ static void l2cap_conn_start(struct l2cap_conn *conn) continue; } - l2cap_start_connection(chan); + if (l2cap_check_enc_key_size(conn->hcon)) + l2cap_start_connection(chan); + else + l2cap_chan_close(chan, ECONNREFUSED); } else if (chan->state == BT_CONNECT2) { struct l2cap_conn_rsp rsp; @@ -3326,16 +3349,22 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data while (len >= L2CAP_CONF_OPT_SIZE) { len -= l2cap_get_conf_opt(&req, &type, &olen, &val); + if (len < 0) + break; hint = type & L2CAP_CONF_HINT; type &= L2CAP_CONF_MASK; switch (type) { case L2CAP_CONF_MTU: + if (olen != 2) + break; mtu = val; break; case L2CAP_CONF_FLUSH_TO: + if (olen != 2) + break; chan->flush_to = val; break; @@ -3343,26 +3372,30 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data break; case L2CAP_CONF_RFC: - if (olen == sizeof(rfc)) - memcpy(&rfc, (void *) val, olen); + if (olen != sizeof(rfc)) + break; + memcpy(&rfc, (void *) val, olen); break; case L2CAP_CONF_FCS: + if (olen != 1) + break; if (val == L2CAP_FCS_NONE) set_bit(CONF_RECV_NO_FCS, &chan->conf_state); break; case L2CAP_CONF_EFS: - if (olen == sizeof(efs)) { - remote_efs = 1; - memcpy(&efs, (void *) val, olen); - } + if (olen != sizeof(efs)) + break; + remote_efs = 1; + memcpy(&efs, (void *) val, olen); break; case L2CAP_CONF_EWS: + if (olen != 2) + break; if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP)) return -ECONNREFUSED; - set_bit(FLAG_EXT_CTRL, &chan->flags); set_bit(CONF_EWS_RECV, &chan->conf_state); chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW; @@ -3372,7 +3405,6 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data default: if (hint) break; - result = L2CAP_CONF_UNKNOWN; *((u8 *) ptr++) = type; break; @@ -3537,58 +3569,65 @@ static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, while (len >= L2CAP_CONF_OPT_SIZE) { len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val); + if (len < 0) + break; switch (type) { case L2CAP_CONF_MTU: + if (olen != 2) + break; if (val < L2CAP_DEFAULT_MIN_MTU) { *result = L2CAP_CONF_UNACCEPT; chan->imtu = L2CAP_DEFAULT_MIN_MTU; } else chan->imtu = val; - l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr); + l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, + endptr - ptr); break; case L2CAP_CONF_FLUSH_TO: + if (olen != 2) + break; chan->flush_to = val; - l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, - 2, chan->flush_to, endptr - ptr); + l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2, + chan->flush_to, endptr - ptr); break; case L2CAP_CONF_RFC: - if (olen == sizeof(rfc)) - memcpy(&rfc, (void *)val, olen); - + if (olen != sizeof(rfc)) + break; + memcpy(&rfc, (void *)val, olen); if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) && rfc.mode != chan->mode) return -ECONNREFUSED; - chan->fcs = 0; - - l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, - sizeof(rfc), (unsigned long) &rfc, endptr - ptr); + l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), + (unsigned long) &rfc, endptr - ptr); break; case L2CAP_CONF_EWS: + if (olen != 2) + break; chan->ack_win = min_t(u16, val, chan->ack_win); l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2, chan->tx_win, endptr - ptr); break; case L2CAP_CONF_EFS: - if (olen == sizeof(efs)) { - memcpy(&efs, (void *)val, olen); - - if (chan->local_stype != L2CAP_SERV_NOTRAFIC && - efs.stype != L2CAP_SERV_NOTRAFIC && - efs.stype != chan->local_stype) - return -ECONNREFUSED; - - l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs), - (unsigned long) &efs, endptr - ptr); - } + if (olen != sizeof(efs)) + break; + memcpy(&efs, (void *)val, olen); + if (chan->local_stype != L2CAP_SERV_NOTRAFIC && + efs.stype != L2CAP_SERV_NOTRAFIC && + efs.stype != chan->local_stype) + return -ECONNREFUSED; + l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs), + (unsigned long) &efs, endptr - ptr); break; case L2CAP_CONF_FCS: + if (olen != 1) + break; if (*result == L2CAP_CONF_PENDING) if (val == L2CAP_FCS_NONE) set_bit(CONF_RECV_NO_FCS, @@ -3717,13 +3756,18 @@ static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len) while (len >= L2CAP_CONF_OPT_SIZE) { len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val); + if (len < 0) + break; switch (type) { case L2CAP_CONF_RFC: - if (olen == sizeof(rfc)) - memcpy(&rfc, (void *)val, olen); + if (olen != sizeof(rfc)) + break; + memcpy(&rfc, (void *)val, olen); break; case L2CAP_CONF_EWS: + if (olen != 2) + break; txwin_ext = val; break; } @@ -4330,6 +4374,12 @@ static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, l2cap_chan_lock(chan); + if (chan->state != BT_DISCONN) { + l2cap_chan_unlock(chan); + mutex_unlock(&conn->chan_lock); + return 0; + } + l2cap_chan_hold(chan); l2cap_chan_del(chan, 0); @@ -4858,10 +4908,8 @@ void __l2cap_physical_cfm(struct l2cap_chan *chan, int result) BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d", chan, result, local_amp_id, remote_amp_id); - if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) { - l2cap_chan_unlock(chan); + if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) return; - } if (chan->state != BT_CONNECTED) { l2cap_do_create(chan, result, local_amp_id, remote_amp_id); @@ -6761,6 +6809,16 @@ static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) chan->sdu_len = sdu_len; chan->sdu_last_frag = skb; + /* Detect if remote is not able to use the selected MPS */ + if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) { + u16 mps_len = skb->len + L2CAP_SDULEN_SIZE; + + /* Adjust the number of credits */ + BT_DBG("chan->mps %u -> %u", chan->mps, mps_len); + chan->mps = mps_len; + l2cap_chan_le_send_credits(chan); + } + return 0; } @@ -7426,7 +7484,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) } if (chan->state == BT_CONNECT) { - if (!status) + if (!status && l2cap_check_enc_key_size(hcon)) l2cap_start_connection(chan); else __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); @@ -7435,7 +7493,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) struct l2cap_conn_rsp rsp; __u16 res, stat; - if (!status) { + if (!status && l2cap_check_enc_key_size(hcon)) { if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { res = L2CAP_CR_PEND; stat = L2CAP_CS_AUTHOR_PEND; |